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单片机温度控制系统毕业论文中英文资料外文翻译文献

单片机温度控制系统毕业论文中英文资料外文翻译文献

单片机温度控制系统中英文资料外文翻译文献英文原文DescriptionThe at89s52 is a low-power, high-performance CMOS 8-bit microcomputer with 4K bytes of Flash Programmable and Erasable Read Only Memory (PEROM) and 128 bytes RAM. The device is manufactured using Atmel’s h igh density nonvolatile memory technology and is compatible with the industry standard MCS-51™ instruction set and pinout. The chip combines a versatile 8-bit CPU with Flash on a monolithic chip, the Atmelat89s52 is a powerful microcomputer which provides a highly flexible and cost effective solution to many embedded control applications.Features:• Compatible with MCS-51™ Products• 4K Bytes of In-System Reprogrammable Flash Memory• Endurance: 1,000 Write/Erase Cycles• Fully Static Operation: 0 Hz to 24 MHz• Three-Level Program Memory Lock• 128 x 8-Bit Internal RAM• 32 Programmable I/O Lines• Two 16-Bit Timer/Counters• Six Interrupt Sources• Programmable Serial Channel• Low Power Idle and Power Down ModesThe at89s52 provides the following standard features: 4K bytes of Flash, 128 bytes of RAM, 32 I/O lines, two 16-bit timer/counters, a five vectortwo-level interrupt architecture, a full duplex serial port, on-chip oscillator and clock circuitry. In addition, the at89s52 is designed with static logic for operation down to zero frequency and supports two software selectable power saving modes. The Idle Mode stops the CPU while allowing the RAM, timer/counters, serial port and interrupt system to continue functioning. The Power Down Mode saves the RAM contents but freezes the oscillator disabling all other chip functions until the next hardware reset.Pin Description:VCC Supply voltage.GND Ground.Port 0Port 0 is an 8-bit open drain bidirectional I/O port. As an output port each pin can sink eight TTL inputs. When is are written to port 0 pins, the pins can be used as high impedance inputs.Port 0 may also be configured to be the multiplexed loworderaddress/data bus during accesses to external program and data memory. In this mode P0 has internal pullups.Port 0 also receives the code bytes during Flash programming, and outputs the code bytes during program verification. External pullups are required during program verification.Port 1Port 1 is an 8-bit bidirectional I/O port with internal pullups. The Port 1 output buffers can sink/source four TTL inputs. When 1s are written to Port 1 pins they are pulled high by the internal pullups and can be used as inputs. As inputs, Port 1 pins that are externally being pulled low will source current (IIL) because of the internal pullups.Port 1 also receives the low-order address bytes during Flash programming and verification.Port 2Port 2 is an 8-bit bidirectional I/O port with internal pullups. The Port 2 output buffers can sink/source four TTL inputs. When 1s are written to Port 2 pins they are pulled high by the internal pullups and can be used as inputs. As inputs, Port 2 pins that are externally being pulled low will source current (IIL) because of the internal pullups.Port 2 emits the high-order address byte during fetches from external program memory and during accesses to external data memory that use 16-bit addresses (MOVX @ DPTR). In this application it uses strong internalpull-ups when emitting 1s. During accesses to external data memory that use 8-bit addresses (MOVX @ RI), Port 2 emits the contents of the P2 Special Function Register.Port 2 also receives the high-order address bits and some control signals during Flash programming and verification.Port 3Port 3 is an 8-bit bidirectional I/O port with internal pullups. The Port 3 output buffers can sink/source four TTL inputs. When 1s are written to Port 3 pins they are pulled high by the internal pullups and can be used as inputs. As inputs, Port 3 pins that are externally being pulled low will source current (IIL) because of the pullups.Port 3 also serves the functions of various special features of theat89s52 as listed below:Port 3 also receives some control signals for Flash programming andverification.RSTReset input. A high on this pin for two machine cycles while theoscillator is running resets the device.ALE/PROGAddress Latch Enable output pulse for latching the low byte of theaddress during accesses to external memory. This pin is also the program pulse input (PROG) during Flash programming.In normal operation ALE is emitted at a constant rate of 1/6 theoscillator frequency, and may be used for external timing or clockingpurposes. Note, however, that one ALE pulse is skipped during each access to external Data Memory.If desired, ALE operation can be disabled by setting bit 0 of SFRlocation 8EH. With the bit set, ALE is active only during a MOVX or MOVC instruction. Otherwise, the pin is weakly pulled high. Setting the ALE-disable bit has no effect if the microcontroller is in external execution mode.PSENProgram Store Enable is the read strobe to external program memory. When the at89s52 is executing code from external program memory, PSEN is activated twice each machine cycle, except that two PSENactivations are skipped during each access to external data memory.EA/VPPExternal Access Enable. EA must be strapped to GND in order to enable the device to fetch code from external program memory locations starting at 0000H up to FFFFH. Note, however, that if lock bit 1 is programmed, EA will be internally latched on reset. Port pinalternate functions P3.0rxd (serial input port) P3.1txd (serial output port) P3.2^int0 (external interrupt0) P3.3^int1 (external interrupt1) P3.4t0 (timer0 external input) P3.5t1 (timer1 external input) P3.6^WR (external data memory write strobe) P3.7 ^rd (external data memory read strobe)EA should be strapped to VCC for internal program executions.This pin also receives the 12-volt programming enable voltage(VPP) during Flash programming, for parts that require 12-volt VPP.XTAL1Input to the inverting oscillator amplifier and input to the internal clock operating circuit.XTAL2Output from the inverting oscillator amplifier.Oscillator CharacteristicsXTAL1 and XTAL2 are the input and output, respectively, of an inverting amplifier which can be configured for use as an on-chip oscillator, as shown in Figure 1. Either a quartz crystal or ceramic resonator may be used. To drive the device from an external clock source, XTAL2 should be left unconnected while XTAL1 is driven as shown in Figure 2. There are no requirements on the duty cycle of the external clock signal, since the input to the internal clocking circuitry is through a divide-by-two flip-flop, but minimum and maximum voltage high and low time specifications must be observed.Idle ModeIn idle mode, the CPU puts itself to sleep while all the onchip peripherals remain active. The mode is invoked by software. The content of the on-chip RAM and all the special functions registers remain unchanged during this mode. The idle mode can be terminated by any enabled interrupt or by a hardware reset.It should be noted that when idle is terminated by a hard ware reset, the device normally resumes program execution, from where it left off, up to two machine cycles before the internal reset algorithm takes control. On-chip hardware inhibits access to internal RAM in this event, but access to the port pins is not inhibited. To eliminate the possibility of an unexpected write to a port pin when Idle is terminated by reset, the instruction following the one that invokes Idle should not be one that writes to a port pin or to external memory.Status of External Pins During Idle and Power Down Modesmode Program memory ALE ^psen Port0 Port1Port2Port3idle internal 1 1 data data data Data Idle External 1 1 float Data data Data Power down Internal 0 0 Data Data Data Data Power down External 0 0 float data Data data Power Down ModeIn the power down mode the oscillator is stopped, and the instructionthat invokes power down is the last instruction executed. The on-chip RAMand Special Function Registers retain their values until the power down modeis terminated. The only exit from power down is a hardware reset. Resetredefines the SFRs but does not change the on-chip RAM. The reset shouldnot be activated before VCC is restored to its normal operating level andmust be held active long enough to allow the oscillator to restart andstabilize.Program Memory Lock BitsOn the chip are three lock bits which can be left unprogrammed (U) orcan be programmed (P) to obtain the additional features listed in the tablebelow:Lock Bit Protection ModesWhen lock bit 1 is programmed, the logic level at the EA pin issampled and latched during reset. If the device is powered up without a reset,the latch initializes to a random value, and holds that value until reset isactivated. It is necessary that the latched value of EA be in agreement with the current logic level at that pin in order for the device to function properly. Programming the Flash:The at89s52 is normally shipped with the on-chip Flash memory array in the erased state (that is, contents = FFH) and ready to be programmed.The programming interface accepts either a high-voltage (12-volt) or alow-voltage (VCC) program enable signal.The low voltage programming mode provides a convenient way to program the at89s52 inside the user’s system, while the high-voltage programming mode is compatible with conventional third party Flash or EPROM programmers.The at89s52 is shipped with either the high-voltage or low-voltage programming mode enabled. The respective top-side marking and device signature codes are listed in the following table.Vpp=12v Vpp=5vTop-side mark at89s52xxxxyywwat89s52xxxx-5yywwsignature (030H)=1EH(031H)=51H(032H)=FFH (030H)=1EH (031H)=51H (032H)=05HThe at89s52 code memory array is programmed byte-bybyte in either programming mode. To program any nonblank byte in the on-chip Flash Programmable and Erasable Read Only Memory, the entire memory must be erased using the Chip Erase Mode.Programming Algorithm:Before programming the at89s52, the address, data and control signals should be set up according to the Flash programming mode table and Figures 3 and 4. To program the at89s52, take the following steps.1. Input the desired memory location on the address lines.2. Input the appropriate data byte on the data lines.3. Activate the correct combination of control signals.4. Raise EA/VPP to 12V for the high-voltage programming mode.5. Pulse ALE/PROG once to program a byte in the Flash array or the lock bits. The byte-write cycle is self-timed and typically takes no more than 1.5 ms. Repeat steps 1 through 5, changing the address and data for the entire array or until the end of the object file is reached.Data Polling: The at89s52 features Data Polling to indicate the end of a write cycle. During a write cycle, an attempted read of the last byte written will result in the complement of the written datum on PO.7. Once the write cycle has been completed, true data are valid on all outputs, and the next cycle may begin. Data Polling may begin any time after a write cycle has been initiated.Ready/Busy: The progress of byte programming can also be monitored by the RDY/BSY output signal. P3.4 is pulled low after ALE goes high during programming to indicate BUSY. P3.4 is pulled high again when programming is done to indicate READY.Program Verify: If lock bits LB1 and LB2 have not been programmed, the programmed code data can be read back via the address and data lines for verification. The lock bits cannot be verified directly. Verification of the lock bits is achieved by observing that their features are enabled.Chip Erase: T he entire Flash Programmable and Erasable Read Only Memory array is erased electrically by using the proper combination of control signals and by holding ALE/PROG low for 10 ms. The code array is written with all “1”s. The chip erase operation must be executed before the code memory can be re-programmed.Reading the Signature Bytes: The signature bytes are read by the same procedure as a normal verification of locations 030H, 031H, and 032H, except that P3.6 and P3.7 must be pulled to a logic low. The values returned are as follows.(030H) = 1EH indicates manufactured by Atmel(031H) = 51H indicates 89C51(032H) = FFH indicates 12V programming(032H) = 05H indicates 5V programmingProgramming InterfaceEvery code byte in the Flash array can be written and the entire array can be erased by using the appropriate combination of control signals. The write operation cycle is selftimed and once initiated, will automatically time itself to completion.中文翻译描述at89s52是美国ATMEL公司生产的低电压,高性能CMOS8位单片机,片内含4Kbytes的快速可擦写的只读程序存储器(PEROM)和128 bytes 的随机存取数据存储器(RAM),器件采用ATMEL公司的高密度、非易失性存储技术生产,兼容标准MCS-51产品指令系统,片内置通用8位中央处理器(CPU)和flish存储单元,功能强大at89s52单片机可为您提供许多高性价比的应用场合,可灵活应用于各种控制领域。

会计内部控制中英文对照外文翻译文献

会计内部控制中英文对照外文翻译文献

会计内部控制中英文对照外文翻译文献(文档含英文原文和中文翻译)内部控制系统披露—一种可替代的管理机制根据代理理论,各种治理机制减少了投资者和管理者之间的代理问题(Jensen and Meckling,1976; Gillan,2006)。

传统上,治理机制已经被认定为内部或外部的。

内部机制包括董事会及其作用、结构和组成(Fama,1980;Fama and Jensen,1983),管理股权(Jensen and Meckling,1976)和激励措施,起监督作用的大股东(Demsetz and Lehn,1985),内部控制系统(Bushman and Smith,2001),规章制度和章程条款(反收购措施)和使用的债务融资(杰森,1993)。

外部控制是由公司控制权市场(Grossman and Hart,1980)、劳动力管理市场(Fama,1980)和产品市场(哈特,1983)施加的控制。

各种各样的金融丑闻,动摇了世界各地的投资者,公司治理最佳实践方式特别强调了内部控制系统在公司治理中起到的重要作用。

内部控制有助于通过提供保证可靠性的财务报告,和临时议会对可能会损害公司经营目标的事项进行评估和风险管理来保护投资者的利益。

这些功能已被的广泛普及内部控制系统架构设计的广泛认可,并指出了内部控制是用以促进效率,减少资产损失风险,帮助保证财务报告的可靠性和对法律法规的遵从(COSO,1992)。

尽管有其相关性,但投资者不能直接观察,因此也无法得到内部控制系统设计和发挥功能的信息,因为它们都是组织内的内在机制、活动和过程(Deumes and Knechel,2008)。

由于投资者考虑到成本维持监控管理其声称的(Jensen and Meckling,1976),内部控制系统在管理激励信息沟通上的特性,以告知投资者内部控制系统的有效性,是当其他监控机制(该公司的股权结构和董事会)比较薄弱,从而为其提供便捷的监控(Leftwich et等, 1981)。

温室环境监测和控制系统外文翻译文献

温室环境监测和控制系统外文翻译文献

温室环境监测和控制系统外文翻译文献(文档含中英文对照即英文原文和中文翻译)New Environment Parameters Monitoring And Control System For Greenhouse Based On Master-slave DistributedAbstractAccording to the actual need of monitoring and control of greenhouse environment parameters in rural areas,a master-slave distributed measurement and control system is designed,in which PC is taken as the host. The system consists of PC ,soil moisture measurement and control module,temperature and humidity, andCO2 monitoring and control module. In the system,PC has large amount of data storage which is easy to make use of fuzzy control expert system,configuration software-KingView is used to develop software for PC,by which the development cycle is shorten and a friendly human-computer interaction is provided.Each monitoring and control module consists of STC12 series of microcontrollers,sensors,relays etc.Different modules are select based on the need if system to achieve control greenhouse in partition and block.I INTRODUCTIONTo modern indoor agriculture, the automatic measurement and control of environment parameters is the key to achieve crop yield and quality of greenhouse.In recent years,facilities agriculture develops vigorously in our country,matched with it,the monitoring and control instrument of greenhouse have also made certain development.After nearly 10 years of unremitting hard work,our research team of measurement and control system of agriculture environment parameters,designed an intelligent measurement and control system of distribution combined of greenhouse which can be popularized in the vast rural areas.This system is mainly control of temperature,humidity,CO2 concentration,soil moisture and illumination of greenhouse.OF SCM,as the data storage is small,display interface is single,amount of information is limited,but its capability price ratio is high,so it is used as a front unit of data acquisition and control;and of PC,it has a large amount of data storage,rich software,convenient human-computer interaction,and so on.If we use outdated and low-priced PC,taking the PC as the upper machine,taking the different function control modules composed of multiple microcomputers as the lower machines,then a master-slave distributed and intelligent control system bases on microcomputer is made up,by which both better monitoring and control,display and data collection or management are achieved,but also lower cost of system is get according to the actual need.II SYSTEM STRUCTURE AND PRINCIPLEThe most marked feature of the distribution combined and intelligent control system greenhouse is that of incorporating with data acquisition, control and management as a whole,module combination, simple structure,convenient human-computer interaction,and using technology of intelligent expert fuzzycontrol,which can adapt to a variety of crop management control in greenhouse.The basic structure of the system is shown in Fig.1.The structure of the distributed system is composed of two layers:the upper and lower.In the top-price PC is taken as the host to make system management and experts fuzzy operation in intelligent,and to provide a friendlyhuman-computer interface,and to realize the united monitoring and management of greenhouse; the lower is composed of a series of modules of different function,and in each module,a single chip of AT89C is adopted as the lower machine,RS485 is used to communicate PC with all AT89C,and then the collection,processing and control of the greenhouse parameters is achieved.Each function module is completely isolated in electrical,any failure on the nodule does not produce any effect on other modules.The system collects separately ways of environment information through each monitoring and control module,and sends it to host PC through the RS485 interface.And in the PC configuration control system,the acquired parameters are compared with the values of setting,then according to a variety of expert intelligent fuzzy control system of crops at different growth stages,the fuzzy control instructions on the environment temperature,humidity,CO2 concentration,soil water content and the corresponding operation instructions or alarm are given.The system is applied in rural greenhouses in ually at 1/4 near East and West end in a greenhouse,and at the height of 1.5m from the ground in the middle in the northern half (near the wet curtain) and the southern half (near the fan ),a module of air temperature and humidity ,CO2 concentration and a module of soil moisture content are set;a module of soil moisture content will be added in the middle of the greenhouse according to the actual condition;at the height of 1.5m in the main entrance,a water tank is set,of which the solenoid of drip tube should be set based on the need and controlled by module of soil moisture content;and the PC is placed in the main entrance to the greenhouse.III HARDWARE DESIGNA.The CP and communication systemIn the distributed system of data acquisition and control,as the micro control unit is limited in data storage and slow in calculating of complex functions,so PC is used and the master-slave module is adopted in the system,that is a system of,taking PC as the host and taking the SCM systems located in the scene as slave.In this distributed system,communication is the key to it.Generally,the serial port of PC is standard RS232,of which transmission distance is shorter.But in agriculture control system.its communication distance is of tens of meters or several kilometers, so RS232/RS485 converter is used to achieve communication between the PC and SCM.To reduce investment,both considering the user convenience and friendly human-computer interaction,low-price PC of above 486 and below PIV is adopted;and considering the operation of configuration software,it is required that memory is 64M or above and hard disk is 10Gb or above.B. The control modules of temperature and humidity,illuminance and CO2 concentrationEach control unit consists of SCM,sensors,signal processing circuit,RS485 interface and output circuit.The hardware structure of module of temperature and humidity,CO2 concentration is shown in Fig.2.CO2concentration is measured by sensor based on NDIR technology,measurement is of 0~2×103mol.Through the sensor,control system,by software of digital filter,linear interpolation and temperature compensation,the CO2 concentration is output as digital adhered to UART protocol,and then is input directly to the SCM.The new intelligent sensor of SHT11 based on CMOSens technology is chosen in the measurement of temperature and humidity.In SHT11,the temperature and humidity sensors,signal amplification,A/D,I2C bus are all integrated in a chip;it has full-scale calibration,second-line digital output,and humidity measuring range of 0~100% RH,temperature measurement range of -40℃~+123.8℃,humidity measurement accuracy of ±3.0% RH,temperature measurement accuracy of ±0.4℃,the response time of <4s.The illuminance sensor of JY1-TBQ-6 of silicon photovoltaic detection is used Light measuring.Its measurement range is 0~200,000 Lux;spectral range is 400~700(nm) visible light;measurement error is less than 2%; output is 4~20mA or 0~20mV;output signal can be directly send to the A/D of the SCM after being amplified to 0~4V.Modules accept the instructions form the the Upper,and output via the output circuit .The output circuit consists of optical isolation,the signal driver and the output relays.C. The measurement and control modules of soil moistureWater is a polar medium, the dielectric constant of the soil containing water is mainly determined by the water,when water content is different,the wave impedance is different.The soil moisture is measured by standing wave radio method in thissystem.Based on the theory of Engineering Electromagnetic Field,for lossy medium,the electromagnetic wave impedance as follows:Z0=√μ/ε(1+jλ/(ωε))Where μ is medium permeability,and μ of soil is μ≈μ0 is the vacuum permeability;ε is medium dielectric constant;λ is medium conductivity;ω is electromagnetic wave frequency.In the very low audio(<2000Hz),the loss tangent of dry soil dielectric is λ/ωε≈0.07,if you choose the frequency of the si gnal source at above 20MHz.then,ε≈ε∞,the imaginary part of the soil wave impedance is neglect,only the real part,which amounts to a pure resistance.Soil moisture sensor consists of 100MHz signal source,a coaxial transmission line and a 4-pin stainless probe.The electromagnetic waves of signal transmit to the probe along the lines.As the probe impedance and line impedance are different,the superimposition of incident waves and reflected waves forms a standing waves.Taking the coaxial transmission line as a lossless uniform line,wave impedance is Z0,Z l is the load impedance.Then the reflected coefficient of voltage wave at the probe is:Γ=(Z L-Z0)/(Z L+Z0)Choosing the length of transmission line is l=λ/4,the maximum and minimum of both ends of the line are U max and U min,Then the standing wave radio in the line can be expressed as:S=U max /U min =(1-|Γ|)/(1+|Γ|)In the way,the soil moisture radio can be measured by measuring the standing wave rate of transmission line.As shown in Fig.3.,soil moisture module consists of sensors and controllers,the sensors are subordinated to controllers,controllers can be omitted without the need of irrigation in greenhouse.To simplify the control,irrigation technology of node-type in partition is adopted in the control soil moisture in this system.To a certain extent,the parameters of upper and lower the ground can be decoupled by adopting this technology.IV CONTROL SYSTEM PROGRAMMINGThe software of PC is developed by KingView 6.51 of Beijing-controlled Asia.This configuration software has high reliability,shorter development cycle,perfect capability of graphical interface generation,and friendly human-computer interaction;and can create dynamic images and charts in accordance with the layout of equipment in the scene;can visually display the changes of parameters,control status,and can give an alarm when over-limited;and can achieve fuzzy control of greenhouse parameters by using the history curve of environment parameters stored in the specific database and adopting the agricultural expert system.The software of SCM of the slave is developed by Keil C51 to achieve real-time collecting,processing,uploading of the parameters and accept the fuzzy control instructions from the host computer and complete local control of the device.A.Program design of the control moduleThe software of the sub-slave machine of soil moisture module,that include the main function,subroutines of data acquisition and processing,interrupt handling andcommunicating etc,read the value of standing wave voltage through the parallel data port and obtained the value of soil moisture content by function calculating.The software of the slave machine of monitoring and control of soil moisture mainly complete data communication with the sub-slave machine,uploading measurement data and current control state to the host computer,accepting the fuzzy control instructions from the host computer and output the implementation instructions.The software of the slave machine of temperature and humidity,and CO2 mainly complete reading data of CO2 concentrations and temperature and humidity through the I2C concentration,uploading measurement data and current control state to the host computer,accepting the fuzzy control instructions from the host computer and output the implementation instructions.The structure of the main program and interrupt subroutine of temperature and humidity module are shown in Fig.4.The serial interrupt mode 3 is adopted by all slaves to communicate with the host,transmit the digital collecting and receive instructions.B. Program design of PC and fuzzy control system1)The communication settings of KingView 6.51:In order to ensure the correctness of communication,the upper and lower must follow the same communication protocol,set the communication ually in communication,master-slave mode is adopted in style and responder is adopted in the process.That is ,the master sent a command to the slave first,then et slave give an answer after receiving the command,thus once communication is completed.In KingView ,a scheduled polling method is adopted to do reading and writing between the lower machine by PC.In the project browser of KingView,first,click device →COM1;in the wizard of device configuration,select intelligent modules→SCM→current SCM of HEX→serial port,and then ser parameters for the host computer’s communication.2)The connection of KingView 6.51 and database:Database is the core of the software,that not only contains the definition of variables,real-time parameters and the historical parameters,but also is needed by parameters alarming,fuzzy calculating,reporting ,and displaying.Access2003 desktop database is used as records database of the system,and by using SQL,it is operated by KingView via ODBC.The procedure is :to create data variables in KingView to create a body of records toestablish a data source of ODBC to create query screens and make the screen connection.To connected with Microsoft Access2003,the functions of SQLConnect(),SQLSelect(),SQLLast(),SQLNext(),SQLFist(),SQLPrew(),SQLInsrt() ,and so on,should be implemented in the command language,and then real-time storage and inquiry of data are completed.3)Software design of PC :For the control system of greenhouse,data storage capacity of the PC is unlimited,so if the existing mature software modules are include into the system,it both be relaxed and can improve the system reliability.The software of software consists of control module and management module.V CONCLUSIONAccording to the economic bearing capacity of farmer in Qinhuangdao ,with the existing technology of monitoring and control of environment parameters of greenhouse,a master-slave distributed automatic control system of greenhouse environment in which PC is taken as the host computer is developed.The system has following characteristics:1)With the large amount of data storage of PC,fuzzy control expert system is easy of data storage,modification and system upgrading.2)By using KingView to develop software of PC,the system reliability is improved,and the development cycle is shorten,and a friendly human-computer interface is get.3)A distributed and modular structure is used in the system,it makes the system maintenance easier and adapts to production needs more. The monitoring and control modules of the slave are connected to the host through the RS485 bus based on needs,then the control of greenhouse in partition or block can be achieved.基于新的温室环境参数监测和控制系统根据实际在农村地区的温室环境参数的监测和控制,主从分布式测量和控制系统的设计需要,以其中一台计算机作为主机,该系统由PC、土壤水分测量和控制模块,温度、湿度、CO2监测和控制模块组成。

电气系统可编程序控制器毕业论文中英文资料外文翻译文献

电气系统可编程序控制器毕业论文中英文资料外文翻译文献

电气系统可编程序控制器中英文资料外文翻译文献英文原文Programmable controller designed for electro-pneumatic systems This project deals with the study of electro-pneumatic systems and theprogrammable controller that provides an effective and easy way to control thesequence of the pneumatic actuators movement and the states of pneumatic system.The project of a specific controller for pneumatic applications join the studyof automation design and the control processing of pneumatic systems with theelectronic design based on microcontrollers to implement the resources of thecontroller.1.IntroductionThe automation systems that use electro-pneumatic technology are formed mainlyby three kinds of elements: actuators or motors, sensors or buttons and controlelements like valves. Nowadays, most of the control elements used to execute thelogic of the system were substituted by the Programmable LogicController(PLC).Sensors and switches are plugged as inputs and the direct controlvalves for the actuators are plugged as outputs. An internal program executes allthe logic necessary to the sequence of the movements, simulates other componentslike counter, timer and control the status of the system.With the use of the PLC the project wins agility, because it is possible tocreate and simulate the system as many times as needed. Therefore, time can besaved, risk of mistakes reduced and complexity can be increased using the sameelements.A conventional PLC, that is possible to find on the market from many companies,offers many resources to control not only pneumatic systems, but all kinds of systemthat uses electrical components. The PLC can be very versatile and robust to beapplied in many kinds of application in the industry or even security system andautomation of buildings.Because of those characteristics, in some applications the PLC offers to much resources that are not even used to control the system, electro-pneumatic system is one of this kind of application. The use of PLC, especially for small size systems, can be very expensive for the automation project.An alternative in this case is to create a specific controller that can offer the exactly size and resources that the project needs[3,4].This can be made using microcontrollers as the base of this controller.The controller, based on microcontroller, can be very specific and adapted to only one kind of machine or it can work as a generic controller that can be programmed as a usual PLC and work with logic that can be changed. All these characteristics depend on what is needed and how much experience the designer has with developing an electronic circuit and firmware for microcontroller. But the main advantage of design the controller with the microcontroller is that the designer has the total knowledge of his controller, which makes it possible to control the size of the controller, change the complexity and the application of it. It means that the project gets more independence from other companies, but at the same time the responsibility of the control of the system stays at the designer hands2.Electro-pneumatic systemOn automation system one can find three basic components mentioned before ,plus a logic circuit that controls the system. An adequate technique is needed to project the logic circuit and integrate all the necessary components to execute the sequence of movements properly.For a simple direct sequence of movement an intuitive method can be used[1,5],but for indirect or more complex sequences the intuition can generate a very complicated circuit and signal mistakes. It is necessary to use another method that can save time of the project, make a clean circuit, can eliminate occasional signal overlapping and redundant circuits.The presented method is called step-by-step or algorithmic [1,5], it is valid for pneumatic and electro-pneumatic systems and it was used as a base in this work. The method consists of designing the systems based on standard circuits made for each change on the state of the actuators, these changes are called steps.Fig.1.Standard circuit for the pneumatic system.Fig.2.Standard circuit for the electro-pneumatic system.The first part is to design those kinds of standard circuits for each step, the next task is to link the standard circuits and the last part to connect the control element that receive signals from sensors, switches and the previous movement and give the air or electricity to the supply lines of each step. In Figs.1 and 2 the standard circuits are drawn for pneumatic and electro-pneumatic system [8].It is possible to see the relations with the previous and the next steps.3. The method applied inside the controllerThe result of the method presented before is a sequence of movements of the actuator that is well defined by steps. It means that each change on the position of the actuators is a new state of the system and the transition between statesis called step.The standard circuit described before helps the designer to define the states of the systems and to define the condition to each change between the states. In the end of the design, the system is defined by a sequence that never chances and states that have the inputs and the outputs well defined. The inputs are the condition for the transition and the outputs are the result of the transition.All the configuration of those steps stays inside of the microcontroller and is executed the same way it was designed. The sequences of strings are programmed inside the controller with 5 bytes; each string has the configuration of one step of the process. There are two bytes for the inputs, one byte for the outputs and two more for the other configurations and auxiliary functions of the step. After programming, this sequence of strings is saved inside of a non-volatile memory of the microcontroller, so they can be read and executed.The controller task is not to work in the same way as a conventional PLC, but the purpose of it is to be an example of a versatile controller that is design for an specific area. A conventional PLC process the control of the system using a cycle where it makes an image of the inputs, execute all the conditions defined by the configuration programmed inside, and then update the state of the outputs. This controller works in a different way, where it read the configuration of the step, wait the condition of inputs to be satisfied, then update the state or the outputs and after that jump to the next step and start the process again.It can generate some limitations, as the fact that this controller cannot execute, inside the program, movements that must be repeated for some time, but this problem can be solved with some external logic components. Another limitation is that the controller cannot be applied on systems that have no sequence. These limitations are a characteristic of the system that must be analyzed for each application.4. Characteristics of the controllerThe controller is based on the MICROCHIP microcontroller PIC16F877 [6,7] with 40 pins, and it has all the resources needed for this project. It ha enough pins for all the components, serial communication implemented in circuit, EEPROM memory to save all the configuration of the system and the sequence of steps. For the execution of the main program, it offers complete resources as timers and interruptions.The list of resources of the controller was created to explore all the capacity of the microcontroller to make it as complete as possible. During the step, the program chooses how to use the resources reading the configuration string of the step. This string has two bytes for digital inputs, one used as a mask and the other one used as a value expected. One byte is used to configure the outputs value. One bytes more is used for the internal timer, the analog input or time-out. The EEPROM memory inside is 256 bytes length that is enough to save the string of the steps, with this characteristic it is possible to save between 48 steps.The controller has also a display and some buttons that are used with an interactive menu to program the sequence of steps and other configurations.4.1.Interaction componentsFor the real application the controller must have some elements to interact with the final user and to offer a complete monitoring of the system resources that are available to the designer while creating the logic control of the pneumatic system:.Interactive mode of work; function available on the main program for didactic purposes, the user gives the signal to execute the step..LCD display, which shows the status of the system, values of inputs, outputs, timer and statistics of the sequence execution..Beep to give important alerts, stop, start and emergency..Leds to show power on and others to show the state of inputs and outputs.4.2. SecurityTo make the final application works property, a correct configuration to execute the steps in the right way is needed, but more then that it must offer solutions in case of bad functioning or problems in the execution of the sequence. The controller offers the possibility to configure two internal virtual circuits that work in parallel to the principal. These two circuits can be used as emergency or reset buttons and can return the system to a certain state at any time[2]. There are two inputs that work with interruption to get an immediate access to these functions. It is possible to configure the position, the buttons and the value of time-out of the system.er interfaceThe sequence of strings can be programmed using the interface elements of the controller. A computer interface can also be used to generate the user program easily. With a good documentation the final user can use the interface to configure the strings of bytes that define the steps of the sequence. But it is possible to create a program with visual resources that works as a translator to the user,it changes his work to the values that the controller understands.To implement the communication between the computer interface and the controller a simple protocol with check sum and number of bytes is the minimum requirements to guarantee the integrity of the data.4.4. FirmwareThe main loop works by reading the strings of the steps from the EEPROM memory that has all the information about the steps.In each step, the status of the system is saved on the memory and it is shown on the display too. Depending of the user configuration, it can use the interruption to work with the emergency circuit or time-out to keep the system safety.A block diagram of micro controller main program is presented.5.Example of electro-pneumatic systemThe system is not a representation of a specific machine, but it is made with some common movements and components found in a real one. The system is composed of four actuators. The actuators A,B and C are double acting and D-single acting. Actuator A advances and stays in specified position till the end of the cycle, it could work fixing an object to the next action for example(Fig.3), it is the first step. When A reaches the end position, actuator C starts his work together with B, making as many cycles as possible during the advancing of B. It depends on how fast actuator B is advancing; the speed is regulated by a flowing control valve. It was the second step. B and C are examples of actuators working together, while B pushes an object slowly, C repeats. its work for some time.Fig.3.Time diagram of A,B,C and D actuators.When B reaches the final position, C stops immediately its cycle and comes back to the initial position. The actuator D is a single acting one with spring return and works together with the back of C, it is the third step. D works making very fast forward and backward movement, just one time. Its backward movement is the fourth step. D could be a tool to make a hole on the object.When D reaches the initial position, A and B return too, it is the fifth step.Fig.4 shows the first part of the designing process where all the movements of each step should be defined[2]. (A+)means that the actuator A moves to the advanced position and (A . )to the initial position. The movements that happen at the same time are joined together in the same step. The system has five steps.Fig.4.Step sequence of A,B,C and D actuators.These two representations of the system(Figs.3 and 4) together are enough to describe correctly all the sequence. With them is possible to design the whole control circuit with the necessary logic components. But till this time, it is not a complete system, because it is missing some auxiliary elements that are not included in this draws because they work in parallel with the main sequence.These auxiliary elements give more function to the circuit and are very important to the final application; the most important of them is the parallel circuit linked with all the others steps. That circuit should be able to stop the sequence at any time and change the state of the actuators to a specific position. This kind of circuit can be used as a reset or emergency buttons.The next Figs.5 and 6 show the result of using the method without the controller. These pictures are the electric diagram of the control circuit of the example, including sensors, buttons and the coils of the electrical valves.Fig.5.Electric diagram of the example.Fig.6.Electric diagram of the example.The auxiliary elements are included, like the automatic/manual switcher that permit a continuous work and the two start buttons that make the operator of a machine use their two hands to start the process, reducing the risk of accidents.6. Changing the example to a user programIn the previous chapter, the electro-pneumatic circuits were presented, used to begin the study of the requires to control a system that work with steps andmust offer all the functional elements to be used in a real application. But, as explained above, using a PLC or this specific controller, the control becomes easier and the complexity can be increase also.It shows a resume of the elements that are necessary to control the presented example.With the time diagram, the step sequence and the elements of the system described in Figs.3 and 4 it is possible to create the configuration of the steps that can be sent to the controller.While using a conventional PLC, the user should pay attention to the logic of the circuit when drawing the electric diagram on the interface (Figs.5and 6), using the programmable controller, describe in this work, the user must know only the concept of the method and program only the configuration of each step.It means that, with a conventional PLC, the user must draw the relation between the lines and the draw makes it hard to differentiate the steps of the sequence. Normally, one needs to execute a simulation on the interface to find mistakes on the logic.The new programming allows that the configuration of the steps be separated, like described by the method. The sequence is defined by itself and the steps are described only by the inputs and outputs for each step.The structure of the configuration follows the order:1-byte: features of the step;2-byte: for the inputs;3-byte: value expected on the inputs;4-byte: value for the outputs;5-byte: value for the extra function.Fig.7.Actuators A and B, and sensors.Fig.8.Actuators C and D, and sensors.Table 5 shows how the user program is saved inside the controller, this is the program that describes the control of the example shown before.The sequence can be defined by 25 bytes. These bytes can be divided in five strings with 5 bytes each that define each step of the sequence (Figs.7 and 8).7. ConclusionThe controller developed for this work shows that it is possible to create a very useful programmable controller based on microcontroller. External memories or external timers were not used in case to explore the resources that the microcontroller offers inside. Outside the microcontroller, there are only components to implement the outputs, inputs, analog input, display for the interface and the serial communication.Using only the internal memory, it is possible to control a pneumatic system that has a sequence with 48 steps if all the resources for all steps are used, but it is possible to reach sixty steps in the case of a simpler system.The programming of the controller does not use PLC languages, but a configuration that is simple and intuitive. With electro-pneumatic system, the programming follows the same technique that was used before to design the system, but here the designer works directly with the states or steps of the system.With a very simple machine language the designer can define all the configuration of the step using four or five bytes. It depends only on his experience to use all the resources of the controller.The controller task is not to work in the same way as a commercial PLC but the purpose of it is to be an example of a versatile controller that is designed for a specific area. Because of that, it is not possible to say which one works better; the system made with microcontroller is an alternative that works in a simple way.References[1]E.Nelli Silva,Fluid-mechanics systems Manual, Escola PolitecnicaUSP,2002(in Portuguese).[2]J.Swider,Control and Automation of Technological Process and Mechatronic systems,Silesian University Publishing Company,Gli-wice,2002(redaction in Polish).[3]J.Swider, G.Wszolek, W.Carvalho. Example of the system prepared to be controlled by the controller based on microcontroller,in:12 International Scientific Conference—Achievements in Mechanical and MaterialsEngineering,Gliwice-Zakopane,Poland,2003,pp.965-970.[4]J.Swider,G.Wszolek,W.Carvalho, Controller based on microcontroller designed to execute the logic control of pneumatic systems, in:12International Scientific Conference— Achievements in Mechanical and Materials Engineering,Gliwice-Zakopane,Poland,2003,pp. 959–964.[5]J.Swider,G.Wszoek, The methodical collection of laboratory and project tasks of technological process control in Pneumatic and Electro-pneumatic Systems with Logical PLC Control, Silesian University Publishing Company,Gliwice,2003.[6]PIC 16f87xDatasheet.MICROCHIP,2001.[7]Application notes AN587 and AN546.MICROCHIP,1997.[8]Fundamental of electro-pneumatic—FESTODidactic,2000.中文翻译应用于电气系统的可编程序控制器摘要此项目主要是研究电气系统以及简单有效的控制气流发动机的程序和气流系统的状态。

关于控制系统中的PLC的选型方法外文文献翻译、中英文翻译、外文翻译

关于控制系统中的PLC的选型方法外文文献翻译、中英文翻译、外文翻译

重庆理工大学文献翻译二级学院班级学生姓名学号关于控制系统中的PLC的选型方法摘要:在设计关于PLC的控制系统时,首先应确定该系统的控制方案,然后下一步工作是为该工程设计选择PLC的型号。

该控制系统运行过程中的特点和应用需求是PLC选型的主要依据。

PLC和相关设备应该根据综合、标准、以及容易形成一个整体的工业控制系统和易扩展其功能的原则选择器件的类型,所选择的PLC应在相关工业领域的有成功的应用成果、该PLC在控制系统中有成熟和可靠的运用制度,该PLC的硬件、软件配置和功能都可适应安装的规模和控制要求。

在设计该系统时知道它所使用的编程控制器,以及它的功能图像及相关的编程语言有利于缩短编程时间,因此,在选择该类型的项目设计和估算时,应先分析该项目的运行过程特点和控制要求,详细地明确该项目的控制任务和范围,根据操作和运动的要求,估算出输入和输出的数量、估计出存储器容量、测定功能的大小以及外部设备性能等,最后选择具有较高的性价比的PLC和相应的控制系统设计。

随着PLC在工业控制系统中的普及,PLC的数量和种类越来越多,功能也日趋完善。

近年来,刚刚介绍的PLC产品已有自美国、日本和德国以及国内厂家组装或独立发展成型,已有几十种系列,几百种型号。

PLC的类型众多,它的结构模型,性能、能力、指令系统和编程方法等各有不同,应用场合也各有不同。

因此,在自动控制系统中合理的选择PLC的型号有很重要的作用。

随着科技的不断进步,PLC的种类是越来越多,其功能也在逐渐增加强。

虽然本文总结了一些选择的方法,以及运用实例说明如何使用PLC,但在实际工作中它还必须做出适当的调整。

需要根据实际条件来用PLC设计工业控制系统,满足期望。

关键词:PLC;选型;控制系统1、介绍PLC的技术随着计算机和微电子技术的发展而得到迅速发展。

从开发出第一台PLC后,随着CPU的应用和单片机技术在PLC中的应用,形成现代意义上的第一台PLC。

自80年代到20世纪的第一个十年,随着微电子技术的大跃进,出现了大规模集成电路和超级大型微电子技术,16通道和32通道的微处理器的出现PLC得到了惊人的开发,这使得PLC在概念、设计、性价比以及应用上获得了新的突破,不仅控制功能增强,功耗和体积减少,成本下降,可靠性上升,编程和故障检测更加灵活和方便,同时远程通信网络、数据处理以及人机界面(HMI)也得到了快速的发展。

可编程控制器本科毕业论文中英文翻译材料关于PLC外文翻译

可编程控制器本科毕业论文中英文翻译材料关于PLC外文翻译

可编程控制器本科毕业论文中英文翻译材料关于PLC外文翻译中文翻译可编程控制器技术可编程序控制器(Programmable Logic Controller,习惯上简称为PLC)是以微处理器为核心的通用工业自动化装置。

是20世纪60年代末在继电器控制系统的基础上开发出来的,它将传统的继电器控制技术与计算机技术和通信技术融为一体,具有结构简单、性能优越、可靠性高、灵活通用、易于编程、使用方便等优点。

具体来说,PLC的特点表现为以下几个方面:?硬件的可靠性高。

PLC专业在工业环境的恶劣条件下应用而设计。

一个设计良好的PLC能置于有很强电噪声、电磁干扰、机械振动、极端温度和湿度很大的环境中。

在硬件设计方面,首先是选用优质器件,再就是采用合理的系统结构,加固、简化安装,使它易于抗振冲击,对印刷电路板的设计、加工和焊接都采取了极为严格的工艺措施,而在电路、结构及工艺上采取了一些独特的方式。

由于PLC 本身具有很高的可靠性,所以在发生故障的部位大多集中在输入/输出的部位以及如传感器件、限位开关、光电开关、电磁阀、电机等外围装置上。

?编程简单,使用方便。

用微机实现自动控制,常使用汇编语言编程,难于掌握,要求使用者具有一定水平的计算机硬件和软件知识。

PLC采用面向控制过程、面向问题的编程方式,与目前微机控制常用的汇编语言相比,虽然在PLC内部增加了解释程序,增加了程序的执行时间,但对大多数的机电控制设备来说,这种损耗是微不足道的。

?接线简单,通用性好。

在电信号匹配的情况下,PLC的接线只需将输入信号的设备(按钮、开关等)与PLC输入端子连接,将接受输出信号执行控制任务的执行元件(接触器、电磁阀)与PLC输出端子连接。

接线简单、工作量少,省去了传统的继电器控制系统的接线和拆线的麻烦。

PLC的编程逻辑提供了能随要求而改变的逻辑关系,这样生产线的自动化过程就能随意改变。

这种性能使PLC具有很高的经济效益。

用于连接现场设备的硬件接口实际上已经设计成为PLC的组成部分,模块化的自诊断接口电路能指出故障,并易于排除故障与替换故障部件,这样的软硬件设计就使现场电气人员与技术人员易于使用。

单片机交通灯控制器论文中英文对照资料外文翻译文献

单片机交通灯控制器论文中英文对照资料外文翻译文献

中英文对照资料外文翻译文献附件1:外文资料翻译译文基于单片机的十字路口交通灯控制器的设计由于我国经济的快速发展从而导致了汽车数量的猛增,大中型城市的城市交通,正面临着严峻的考验,从而导致交通问题日益严重,其主要表现如下:交通事故频发,对人类生命安全造成极大威胁;交通拥堵严重,导致出行时间增加,能源消耗加大;空气污染和噪声污染程度日益加深等。

日常的交通堵塞成为人们司空见惯而又不得不忍受的问题。

在这种背景下,结合我国城市道路交通的实际情况,开发出真正适合我们自身特点的智能信号灯控制系统已经成为当前的主要任务。

前言在实际应用上,根据对国内外实际交通信号控制应用的考察,平面独立交叉口信号控制基本采用定周期、多时段定周期、半感应、全感应等几种方式。

前两种控制方式完全是基于对平面交叉口既往交通流数据的统计调查,由于交通流存在的变化性和随机性,这两种方式都具有通行效率低、方案易老化的缺陷,而半感应式和全感应式这两种方式是在前两种方式的基础上增加了车辆检测器并根据其提供的信息来调整周期长和绿信比,它对车辆随机到达的适应性较大,可使车辆在停车线前尽可能少停车,达到交通流畅的效果。

在现代化的工业生产中,电流、电压、温度、压力、流量、流速和开关量都是常用的主要被控参数。

例如:在冶金工业、化工生产、电力工程、造纸行业、机械制造和食品加工等诸多领域中,人们都需要对交通进行有序的控制。

采用单片机来对交通进行控制,不仅具有控制方便、组态简单和灵活性大等优点,而且可以大幅度提高被控制量的技术指标,从而能够大大提高产品的质量和数量。

因此,单片机对交通灯的控制问题是一个工业生产中经常会遇到的问题。

在工业生产中,有很多行业有大量的交通灯设备,在现行系统中,大多数的交通控制信号都是用继电器来完成的,但继电器响应时间长,灵敏度低,长期使用之后,故障机会大大增加,而采用单片机控制,其精度远远大于继电器,响应时间短,软件可靠性高,不会因为工作时间缘故而降低其性能,相比而言,本方案具有很高的可行性。

智能住宅安防报警和远程控制系统中英文对照外文翻译文献

智能住宅安防报警和远程控制系统中英文对照外文翻译文献

中英文资料对照外文翻译基于单片机的智能住宅安防报警和远程控制系统摘要:为了对偷盗,抢劫和意外事故进行有效的监控和警告,统一使用单片机AT89C51的控制技术和红外探测技术,设计了一种无线防盗报警器,它包括硬件和软件两部分;硬件部分是由红外线感应器,发送和接收模块,单片机,声光报警等组成;软件部分是由主程序和音乐子程序组成。

采用C或汇编语言编写的源程序,在Keilc51平台上进行翻译和调试后,下载到单片机AT89C51芯片,并根据焊接在PCB板上的此单片机和其他主要设备设计一个电路。

对于电源,闭路循环控制开关,当有人入侵红外线发射区,产生声光报警,表示已经达到设计要求,这个项目展示了智能化住宅防盗报警,紧急报警,火灾报警器,有毒气体泄漏远程自动声音报警及远程控制系统,它是基于89C51单片机。

该系统可自动报警,自动致电警方热线电话号码。

它可用于语音报警,并显示发生报警的地址。

它可以设置和修改用户的密码。

它可以进行录制和语音提示。

它可用于电话远程控制电源。

该报警系统设计创新,具有多功能,成本低,可靠性高等诸多特点。

随着时代的不断进步,人们对自己的居住环境安全提出了更高的要求,不仅在生活,特别是在安全方面,一定要注意这些频繁发生的意外。

现在,许多区域已安装了智能报警系统,从而大大提高居住区的安全率,因为红外线是一种黑色的光,使用无线发射和接收,无需独立的布线,它具有很强的保密性和保密性,从而在安全,安保部分等安全领域的应用应该有很大的优势。

关键词:红外传感;发射;接收;单片机;警告一、简介随着计算机技术和控制技术及通信技术的发展,人民生活水平日益改善。

人民的生活条件已经发生了变化,例如产生了居住环境的安全和如何使他们生活得更加舒适等问题。

因此,智能化的住宅建筑的自动控制的出现顺应了时代的要求。

智能化小区必须有安全防范,防盗报警,火灾报警器,有毒气体泄漏自动报警和紧急呼叫等功能。

关键设备电源的远程控制是能够实现的。

微控制器论文中英文资料对照外文翻译

微控制器论文中英文资料对照外文翻译

中英文资料对照外文翻译微控制器早期的单片机都是8位或4位的。

其中最成功的是INTEL的8031 因为简单可靠而性能不错获得了很大的好评。

此后在8031上发展出了MCS51系列单片机系统。

基于这一系统的单片机系统直到现在还在广泛使用。

随着工业控制领域要求的提高开始出现了16位单片机但因为性价比不理想并未得到很广泛的应用。

90年代后随着消费电子产品大发展单片机技术得到了巨大提高。

随着INTEL i960系列特别是后来的ARM系列的广泛应用 32位单片机迅速取代16位单片机的高端地位并且进入主流市场。

而传统的8位单片机的性能也得到了飞速提高处理能力比起80年代提高了数百倍。

目前高端的32位单片机主频已经超过300MHz 性能直追90年代中期的专用处理器而普通的型号出厂价格跌落至1美元最高端[1]的型号也只有10美元。

当代单片机系统已经不再只在裸机环境下开发和使用大量专用的嵌入式操作系统被广泛应用在全系列的单片机上。

而在作为掌上电脑和手机核心处理的高端单片机甚至可以直接使用专用的Windows和Linux操作系统。

单片机也被称为微控制器MICROCONTROLLER UNIT常用英文字母的缩写MCU表示单片机它最早是被用在工业控制领域。

单片机由芯片内仅有CPU的专用处理器发展而来。

最早的设计理念是通过将大量外围设备和CPU集成在一个芯片中使计算机系统更小更容易集成进复杂的而对体积要求严格的控制设备当中。

INTEL的Z80是最早按照这种思想设计出的处理器从此以后单片机和专用处理器的发展便分道扬镳。

单片机比专用处理器更适合应用于嵌入式系统因此它得到了最多的应用。

事实上单片机是世界上数量最多的计算机。

现代人类生活中所用的几乎每件电子和机械产品中都会集成有单片机。

手机、电话、计算器、家用电器、电子玩具、掌上电脑以及鼠标等电脑配件中都配有1-2部单片机。

而个人电脑中也会有为数不少的单片机在工作。

汽车上一般配备40多部单片机复杂的工业控制系统上甚至可能有数百台单片机在同时工作单片机的数量不仅远超过PC机和其他计算的总和甚至比人类的数量还要多。

温度控制系统中英文对照外文翻译文献

温度控制系统中英文对照外文翻译文献

温度控制系统中英文对照外文翻译文献温度控制系统中英文对照外文翻译文献温度控制系统中英文对照外文翻译文献(文档含英文原文和中文翻译)译文:温度控制系统的设计摘要:研究了基于AT89S 51单片机温度控制系统的原理和功能,温度测量单元由单总线数字温度传感器DS18B 20构成。

该系统可进行温度设定,时间显示和保存监测数据。

如果温度超过任意设置的上限和下限值,系统将报警并可以和自动控制的实现,从而达到温度监测智能一定范围内。

基于系统的原理,很容易使其他各种非线性控制系统,只要软件设计合理的改变。

该系统已被证明是准确的,可靠和满意通过现场实践。

践。

关键词:单片机;温度;温度关键词:单片机;温度;温度I. 导言温度是在人类生活中非常重要的参数。

在现代社会中,温度控制(TC TC)不仅用于工业生产,还广泛应用于其它领域。

随着生活质量的提)不仅用于工业生产,还广泛应用于其它领域。

随着生活质量的提高,我们可以发现在酒店,工厂和家庭,以及比赛设备。

而比赛的趋势将更好地服务于整个社会,因此它具有十分重要的意义测量和控制温度。

度。

在AT89S51AT89S51单片机和温度传感器单片机和温度传感器DS18B20DS18B20的基础上,系统环境的基础上,系统环境温度智能控制。

温度可设定在一定范围内动任意。

该系统可以显示在液晶显示屏的时间,并保存监测数据,并自动地控制温度,当环境温度超过上限和下限的值。

这样做是为了保持温度不变。

该系统具有很高的抗干扰能力,控制精度高,灵活的设计,它也非常适合这个恶劣的环境。

它主要应用于人们的生活,改善工作和生活质量。

这也是通用的,因此它可以方便地扩大使用该系统。

因此,设计具有深刻的重要性。

一般的设计,硬件设计和软件系统的设计都包括在内。

设计,硬件设计和软件系统的设计都包括在内。

II. 系统总体设计该系统硬件包括微控制器,温度检测电路,键盘控制电路,时钟电路,显示,报警,驱动电路和外部RAM RAM。

DCS分布式控制系统中英文资料对照外文翻译文献综述

DCS分布式控制系统中英文资料对照外文翻译文献综述

DCS分布式控制系统中英文资料对照外文翻译文献综述中文:DCSDCS是分布式控制系统的英文缩写(Distributed Control System),在国内自控行业又称之为集散控制系统。

即所谓的分布式控制系统,或在有些资料中称之为集散系统,是相对于集中式控制系统而言的一种新型计算机控制系统,它是在集中式控制系统的基础上发展、演变而来的。

它是一个由过程控制级和过程监控级组成的以通信网络为纽带的多级计算机系统,综合了计算机,通信、显示和控制等4C技术,其基本思想是分散控制、集中操作、分级管理、配置灵活以及组态方便。

在系统功能方面,DCS和集中式控制系统的区别不大,但在系统功能的实现方法上却完全不同。

首先,DCS的骨架—系统网络,它是DCS的基础和核心。

由于网络对于DCS 整个系统的实时性、可靠性和扩充性,起着决定性的作用,因此各厂家都在这方面进行了精心的设计。

对于DCS的系统网络来说,它必须满足实时性的要求,即在确定的时间限度内完成信息的传送。

这里所说的“确定”的时间限度,是指在无论何种情况下,信息传送都能在这个时间限度内完成,而这个时间限度则是根据被控制过程的实时性要求确定的。

因此,衡量系统网络性能的指标并不是网络的速率,即通常所说的每秒比特数(bps),而是系统网络的实时性,即能在多长的时间内确保所需信息的传输完成。

系统网络还必须非常可靠,无论在任何情况下,网络通信都不能中断,因此多数厂家的DCS均采用双总线、环形或双重星形的网络拓扑结构。

为了满足系统扩充性的要求,系统网络上可接入的最大节点数量应比实际使用的节点数量大若干倍。

这样,一方面可以随时增加新的节点,另一方面也可以使系统网络运行于较轻的通信负荷状态,以确保系统的实时性和可靠性。

在系统实际运行过程中,各个节点的上网和下网是随时可能发生的,特别是操作员站,这样,网络重构会经常进行,而这种操作绝对不能影响系统的正常运行,因此,系统网络应该具有很强在线网络重构功能。

DCS分布式控制系统论文中英文资料对照外文翻译文献综述

DCS分布式控制系统论文中英文资料对照外文翻译文献综述

DCS分布式控制系统中英文资料对照外文翻译文献综述中文:DCSDCS是分布式控制系统的英文缩写(Distributed Control System),在国内自控行业又称之为集散控制系统。

即所谓的分布式控制系统,或在有些资料中称之为集散系统,是相对于集中式控制系统而言的一种新型计算机控制系统,它是在集中式控制系统的基础上发展、演变而来的。

它是一个由过程控制级和过程监控级组成的以通信网络为纽带的多级计算机系统,综合了计算机,通信、显示和控制等4C技术,其基本思想是分散控制、集中操作、分级管理、配置灵活以及组态方便。

在系统功能方面,DCS和集中式控制系统的区别不大,但在系统功能的实现方法上却完全不同。

首先,DCS的骨架—系统网络,它是DCS的基础和核心。

由于网络对于DCS 整个系统的实时性、可靠性和扩充性,起着决定性的作用,因此各厂家都在这方面进行了精心的设计。

对于DCS的系统网络来说,它必须满足实时性的要求,即在确定的时间限度内完成信息的传送。

这里所说的“确定”的时间限度,是指在无论何种情况下,信息传送都能在这个时间限度内完成,而这个时间限度则是根据被控制过程的实时性要求确定的。

因此,衡量系统网络性能的指标并不是网络的速率,即通常所说的每秒比特数(bps),而是系统网络的实时性,即能在多长的时间内确保所需信息的传输完成。

系统网络还必须非常可靠,无论在任何情况下,网络通信都不能中断,因此多数厂家的DCS均采用双总线、环形或双重星形的网络拓扑结构。

为了满足系统扩充性的要求,系统网络上可接入的最大节点数量应比实际使用的节点数量大若干倍。

这样,一方面可以随时增加新的节点,另一方面也可以使系统网络运行于较轻的通信负荷状态,以确保系统的实时性和可靠性。

在系统实际运行过程中,各个节点的上网和下网是随时可能发生的,特别是操作员站,这样,网络重构会经常进行,而这种操作绝对不能影响系统的正常运行,因此,系统网络应该具有很强在线网络重构功能。

中英文翻译

中英文翻译

NC switching power supplyAbstract:This system based on 51 SCM control unit, used for LM2576-wild numerical control a switching power supply of fuzzy digital control technology, adjust load R1, R2 proportion to change occupies empties compared to make the output stability, and can be through the buttons, digital display to realize output voltage numerical control. In addition, the system to input pressure, flow, input output flow, switch tube overheat as well as the protection circuit, ensure that the system is stable and reliable.Key words:the numerical control,switching power supply,LM2576-wild,micro controller (一)The overall design of the systemSystem to monolithic integrated circuit AT89S52, LM2576-for the core part, and the wild through the monolithic integrated circuit to output voltage gather, comparison, operations, and the output voltage control, automatic regulation system structure diagram shown as shown in figure 1.220 V / 50 Hz ac voltage after rectifying circuit and DC/DC voltage chip LM2576 wild transformation for stable-5 ~ 12 V DC voltage output, the output voltage through sampling circuit by sampling, A/D conversion chip ADC0804 after converting to 52 after processing, control simulation electron switch to choose 4051 respectively the nine potentiometer R2, change R1 and R2 ratio values, which change LM2576-of the wild chip PWM pulse of empty, MOS tubes work than to switch state in, the input of 15 V DC voltage "chopped" for the and of the same frequency PWM waves pulse wave, pulse wave through the rectifier filter circuit output for 5 ~ 12 V DC voltage. Because of this the topic request have nine output stepping demand, so can tune in advance each voltage resistance, through the corresponding key choice output voltage, directly to the analog switch 4067 choose resistance, they can get to output voltage. At the same time, to detect the voltage, current value through the display LCD1062 real-time display. If working current is too big, the flow detection circuit will be sent to the testing results of single-chip microcomputer, SCM control relaythrough the ac branch realize over-current protection system in fault, after the operation is set by the reset button to may cause the system to resume normal work. (二)The block diagram of the whole system(三) Unit circuit function and the analysis of the operation1. Minimum AT89S52 SCM systemMinimum system including crystal oscillator circuit and reset switch and power supply parts. Figure 2 for the minimum AT89S52 SCM system.The wave rectifier circuit is made up of two half wave of rectifier circuit. Because in the next two, add on miens input voltage of the opposite polarity, therefore, to a dynamic balance, in every signal cycle, the C1 and C2 experience 2 times charger, discharge process, current will appear two current pulse with polarity. So in addition to the V o saw tooth wave on the wavy frequency, improve the ability of double filtering, thus reduce ripple voltage.The dc power by power supply, filtering, protection, such as voltage, four basic modules.(1)The power transformer USES a step-down transformer, the power grid voltage 220 V transform into need ac voltage. The ac voltageAfter rectifying, may obtain electronic equipment need dc voltage.(2) Use rectifier circuit bridge rectifier circuit single-phase, 50 Hz ac alternating current transformation for direction invariable but still has the pulse size straight Flow electricity. Its advantage is high voltage ripple voltage, small, the utilization rate of transformer high. This design by A bridge pile of bridge rectifier, RS808 do maximum current can reach 8 A, cooperate with the design of the large filter capacitance, so the power of the instantaneous large current power supply characteristics, low noise, good reaction speed, output ripple small.(3)Filter circuit using capacitance filter circuit, will the pulsation of the rectifier circuit output filter, get most of the components is smooth dc the electricity. This circuit adopts 4700 u F / 50 V large capacitance C3, C4 to make the output voltage more smooth, the power supply characteristics moment, suitable for take the perceptual load, such as motor start-up. C3, C4 every parallel connection a 0.1 u F / 63 V CBB capacitance, filter to high frequency interference, make input to integrated circuits L11, L12 of dc as far as possible the smooth and pure.(4)By LM317 output voltage circuit is power, LM337 output negative supply. LM317 and LM337 are used internal heat Load, contains over current protection, hot off and safety working area for perfect protection circuit, that power can save the fuse, and so easy loss device. Regulating circuit: to meet the needs of the differentapplication situation and the voltage is set to can be adjusted. The calculation of the output voltage V o = 1.25 x (1 + Rf/R), adjustable resistance in use precision can be resistor and guarantee the precise output voltage can be adjusted. If this article chooses for 5 k of Rf Ω, R for 270 Ω combination, can respectively on 1.25 V ~ 24 V 1.25 V ~ 24 V achieve continuous adjustable between.(5)Protection circuit for linear power supply heat, so the power larger add enough radiator. Due to the high performance integrated circuit, which can simplify the circuit structure, highlighting the important part in the power transformation. Through the commissioning and testing, good performance. The whole circuit The power not only can be used alone, also can be in other electronic equipment used in voltage or current stabilization source use.2. LM2576-voltage circuit wildWorking principle:Assume that the switch transistors, diodes are ideal components, inductance and capacitance is ideal components, the output voltage ripple voltage output voltage and the ratio of the small to allow oversight.According to the current cycle to begin in IL inductance is starting from scratch, can be divided into current continuous working mode and inductance inductive current is discontinuous work patterns. Due to the continuous work mode inductance current converter, have very good control characteristic; Inductive current is discontinuous work mode, put the electric, inductance and capacitance easy to produce the oscillation, thus affecting the output voltage ripple; And the same occupies empties compared, output voltage in discrete model under the mode of work than the big, high efficiency. To sum up, the most ideal situation is in critical condition, stabilizer which work so we use two kinds of methods:(1)The increase of the inductance inductive energy storage, increase, and extend the discharge of time(2)Improve the work and reduce the frequency switch timeMake transistor in current continuous state.3. The whole wave output rectifier circuit parameter analysisOutput filter by free-wheeling diode rectifier circuit, inductance and capacitance composition. Consider free-wheeling diode in tube by PMOS transistor conduction, when energy consumption, and work in the state, so we used the low power consumption, high current, high-speed Scotty diodes IN5817, the characteristics as follows:Maximum peak reverse voltage: 40 VThe biggest reverse RMS voltage: 28 VThe biggest dc voltage: 40 V blockThe biggest positive average rectifier current: 1 AThe biggest positive pressure drop: 0.6 V (1 A) BUCK converter principle by analysis shows that in order to make work in inductive current circuit continuous mode, and the ripple voltage2221()88o o o s s V V D V t t T T LC LC=-= So as far as possible, should be made great inductance we choose for 8 mH inductanceCapacitors mainly is the "absorb" ripple with a smooth, the role of the voltage waveform. Capacitance and inductance is equivalent to a low pass filtering filter, the cut-off frequency defined asfc=Considering thecapacitance equivalent series resistance losses, we choose the capacitance for 1000 uF.562c f Hz ==≈ ()(2~4)gs th V V =-- At this time the cut-off frequency of ab o ut 562 Hz ac, visible to dozens of kHz PWM waves have very good filtering effect.4. Input over-voltage protectionWhen the input voltage in the normal range, the input sampling voltage comparator, less than the benchmark voltage output low level; When the input pressure, input voltage is greater than the benchmark sampling comparison output voltage, high level, ARM produce external interruption, warning, blockade, make PMOS transistor tube PWM signal, in order to protect the circuit damage.5. Over-current protectionUsually with hall current sensor detection of current directly PMOS transistor, and then with setting the Id threshold value, compared with comparison to control the output of the driver signal shut off; Or by indirect method, the flow test voltage when the voltage drop the Vsd PMOS transistor, because the pressure drop contains short-circuit current information flow, when the Vsd increasing, and basically for linear relationship, when the Vsd and with setting the threshold value is used in the comparison, the comparator output control power circuit of the shutoff.数控开关稳压电源摘要:本系统基于51单片机为控制单元,采用LM2576-ADJ数控开关稳压电源中的模糊数字控制技术,调整负载R1,R2比例来改变占空比使输出稳定,并且可通过按键、数码显示实现输出电压数控。

智能医院控制系统中英文对照外文翻译文献

智能医院控制系统中英文对照外文翻译文献

智能医院控制系统中英文对照外文翻译文献(文档含英文原文和中文翻译)原文:2.4GHz T-bus EIB smart hospital control system Modernized hospital construction function is complicated, medical equipment is precise, the environment request standard is high, using 2.4GHz T-bus intelligence control system can connect to the hospital construction environment. Through the establishment of digitization energy conservation medical service environment, may enhance the hospital management level, enhances medical personnel's working efficiency, save the hospital operation costs. T-bus intelligence environment control system realize the optimizing control to the light environment, the visor environment,the temperature environment and the medical equipment movement and maintenance of many hospital departments such as outpatient clinic, the in-patient department and so on through controlling to each kind of terminal electrical equipment (for example light, electrical window curtain, air conditioners, medical equipment and so on).Purposes:1. Uniformly Manages, controls and protects the hospital illumination, air conditioners and the medical equipment2. Enhances the hospital service scale, provides the comfortable environment to the medical person and the patients.3. Save the energy, saves the hospital operation costs4. uses the safe voltage the weak electricity board to substitute the strong electricity board, enhanced the security; Through the electric current and the leakage electric current examination to the important medical equipment, promptly reported in the breakdown situation, strengthened the medical equipment reliability and security. Functions:1. Light control of ward and outpatient service building2. Electrical window curtain and visor volume curtain control of ward and outpatient service building3. Air conditioner, heats up and the air blower plate tube control of ward and outpatient service building4. Illumination and the light adjusting of the operating room and the treatment room5. Hospital ward ringing system6. AV device control of academic exchange center and conference room7. Illumination electrical power distribution system and fire linkage8. Linkage hospital automation office system, to realize to have no paper work9. All T-bus system intelligent controllers circuit breaker of Outpatient service andin-patient department and important medical equipment circuit breaker condition surveillance10. Centralism monitor and control of the outpatient service and the hospital ward to achieve the non- board control in the public regionControlled area and control content:1. hospital wardControl of light, electric curtain, fan coil unit, ringing system, the socket of microwave oven and so on , ultraviolet ray sterilization lamp2. Outpatient service hallControl of light, visor volume curtain, fan coil unit3. The departments of the treatment, the inspection, the surgery, the diagnosis, rescue and so on.Control of light, electric curtain, fan coil unit4. Common aisle, elevator hallControl of light, underground lamp control5. Academic exchange center, report hallControl of light, AV equipment, window electric curtain, theater curtain;6. Extensive lighting, botanical garden illuminationControl of light7. Center control computerSolutions:1. Hospital ward* Installs 8 path 2.4GHz T-bus system intelligent controllers beside the bed, controls the light switch and adjusts the light in the guest room, controls the opening and closing of the electric curtain, may carry on the master switch control to the hospital ward light, may control the bathroom light, and may set the doctors clinic scene, the rest scene, the television watching scene.* The angle of the hospital ward electrically operated bed can be adjusted through the T-bus system intelligent controllers and the remote control, facilitates the doctors clinic and the patient dines, reads;* Guardianship ringing system. When the patient needs the guardianship the patient’s feeling is not good, may press the call button or the remote control nearby the bed, the on-duty nurse may rush to the hospital ward to carry on processing immediately;* The center control computer in Each floor nurse stand can implement the common control to various illumination, the curtain and the air-conditioner system at hospital wards in corresponding floor, and the computer of each nurse stand can demonstrate the indoor temperature in each hospital ward, simultaneously may establish the maximum and minimum temperature, provides the human nature service;* The hospital ward corridor illumination may automatically open by coordinating with the light sensor and the timers, when the degree of illumination request is very low at the deeper night, shuts down partial illuminations light, the foot light automatically opens.* The nurse station may realize centralism monitoring to the sockets of various medical equipments such as breath machine and so on in the ward.* Installs a intelligent switch with a temperature control board at the entrance, carries on the automatic constant temperature control to the fan coil unit of the hospital ward, may demonstrate the indoor temperature, simultaneously may carry on the control to the light and the curtain.* Installs intelligence switch at the bathroom entrance, may carry on the control to the bathroom light and the ventilating fan* If with intelligent door lock system linkage, may realize the different opening gate pattern between the doctor and the service person, named the clinic pattern and the sweeps clear pattern.* After the patient Check-in, automatically adjusts the light and the electric curtain at the corresponding ward to in-patient pattern, adjusts the air conditioner temperature to comfortable temperature. Enables the patient to have the home feeling and enhancesthe hospital service scale.* After the patient left, automatically adjusts the light and the electric curtain at the corresponding ward to closure pattern, may automatically restore the ward hypothesis temperature to the condition which tacitly approves.* After the patient goes to sleep at night, T-bus temperature controls board automatically changes to energy conservation pattern. According to the statistics, the hypothesis temperature elevates 1 (when refrigeration) or reduces 1 (when heats up) every time, may conserve energy 6%* The center control room may demonstrate the actual temperature and the hypothesis temperature of each hospital ward. Also may set the maximum and minimum temperature. Simultaneously the hospital ward temperature control also may connect with the window linkage, after the window is turned on, automatically closes the air conditioner to realize energy conservation fully.* T-bus temperature controls board can automatically control Fan coil unit. When the indoor temperature approaches the hypothesis temperature, automatically adjusts wind speed from high to low, makes the indoor temperature to maintain around the hypothesis temperature, to save energy and it is very comfortable.* When summer sunlight is intense, automatically shut-off ward curtain, prevented the ward temperature to be excessively high, achieves the energy conservation purpose.2. Outpatient service hall* Automatically control degree of illumination of the outpatient hall through lit sensor at day time. When the natural light is intense, closes partial lights, otherwise, then opens the certain light, makes the outpatient hall to maintain the constant degree of illumination. Simultaneously may conserve energy.* At night may act different degree of illumination according to the patient current capacity.* Controls the visor volume curtain of the hall through the light sensor. When the summer light is intense, automatically lays down the visor volume curtain, in order to conserves energy.* May control the light, the visor volume curtain of the out patient hall through the center control room computer.3. The treatment of the inspection, the surgery, the diagnosis, the rescue and so on* The operating room, the requirement of general degree of illumination is not lower than 1000Lux. The shadowless lamp took as the local lighting, should achieve above 20000Lux in the surgery table 30cm scope. May adjust the light to the auxiliary light source through the T-bus system intelligent controllers board or the remote control, may adjusts the light scope from 0% to 100%.According to different operating room illumination degree, specially the local lighting degree of illumination is different, May adjust the light source degree of illumination to carry on the pre- establishment.Through illumination degree sensor established in the operating room, carry on the precise adjustment of illumination degree to some work surface.* Regards the functional checking room (mainly refer to ophthalmology department), its requirement of illumination degree reaches as high as7500Lux. Through the T-bus system intelligent controller board and the remote control, may adjust the light scope according to the hospital illumination standard request to the 50Lux scope;In regards the mirror inspection room, X perspective room, the ophthalmology department darkroom and so on the degree of illumination is in the 50-100Lux scope, may adjust the light to 0Lux.through the T-bus system intelligent controller board and the remote control.* stalls the electric current and the leakage electric current examination module regarding the below important advanced equipment, like spiral CT, colored Doppler B ultra machine, the entire automatic blood congeals analyzer, the entire automatic chemistry lighting immunity analyzer, 24 hours dynamic electroencephalogram meter, straight vertical D5-3 machine, the central guardianship system and the breath machine and so on.Through the electric current and the leakage electric current examination to the equipment , early discovered equipment hidden danger, reported to the relative maintenance department before the equipment failure at an earlier time, reduced the life and property lose caused by the equipment failure, reduced the maintenance work load, strengthened the medical equipment security and reliability.* the surveillance of the medical equipment power supply and circuit breaker condition, any artificial or the breakdown trips will promptly feed back the system and recognize it, noticed to the service man.After the reserve power source starts, the system should provide the urgent light control function, only provides the power source to the urgent light return route in and prohibits normal light return route control.In the outpatient service consulting room, the treatment room, the rescue room, the small operating room, the gynecology and obstetrics department, infect ward, the tumor ward, the burn ward, the newborn room, the cardiovascular room and so on are equipped with the stationary installment ultraviolet ray sterilization lamp, may suppose the independent controlling switch, and uses the timer to carry on the timed control.4. common aisle, elevator hall* Select sensor and time setting coordinates to control the light, opens completely or the majority of lights when daytime person current capacity great , after the midnight closes the majority of lights, simultaneously starts the human body sensor, when some people appear, opens the corresponding region light, conserves energy in maximum way.* When nature sunshine is good, does not turn on the light to save the energy; When cloudy day or darkness, turn on the light according to the personnel needs;* May connect with the fire linkage, when the fire appearing, may realize the lamp luminous intensity to cut or the strong point function, start emergency lighting control.5. Academic exchange center, report hall, multi-purpose hall* Installs 2.4GHz T-bus system intelligent controller in the conference room, T-bus system intelligent controller has the light scene control function, temperature control and remote control functions;* Installs the human body sensor in the conference room, may achieve somebody to turn on and turn off the light the air conditioner, nobody to turn on and turn off the light the air conditioner, in order to avoid waste if forgetting to close;* Installs the touch screen computer in the report panel, through the graphical interface of the touch screen to carry on each kind of light scene and the AV scene control: Conference scene, lecture scene, rest scene, showing scene and so on; Showing scene description: Presses “one key scene " of the remote control”, the light adjusts in the room, the projection theater curtain lays down, the curtain lays down, the projecting apparatus opens, the merit puts /DVD opens, all in instantaneous completes.* Installs the T-bus intelligence switch, this board has the light scene control function, simultaneously has locking (to guard against wrong operation) function.6. Extensive lighting, botanical garden illumination* The hotel extensive lighting and the botanical garden illumination may select the method which the lit sensor and time setting coordinates to carry on the automatic control.* When the natural lit changes dark, the light sensor automatically opens the majority of extensive lighting and the garden illumination, when at night for example 12o'clock PM, sets time and the partial extensive lighting and the botanical garden illumination closes, leaves few base lightings only, the light sensor can turn off the left lights when the day is coming. The whole process is automatic and energy conservation.7.Center control computer*Through the computer graph surface may carry on the centralism monitoring and control to the each equipment such as various region light, air conditioners, electric curtain, HVAC, AV and so on.* May carry on the event record, in order to processes;* when any chapter of light appears the breakdown, may inform the administrator immediately.* Through the computer carry on the accumulation of the using times of exude light, common aisle, elevator hall, great hall and so on , in order to promptly services the replacement;* May demonstrate each region temperature, may simultaneously set the maximum and minimum temperature of various region, avoids energy wasting.翻译:2.4GHz T-bus EIB智能化医院控制系统现代化医院的建筑功能复杂,医疗设备精密,对环境标准要求高,用2.4GHz T-bus 智能控制系统能够与医院的建筑环境相结合。

直流电动机闭环控制系统毕业论文中英文资料外文翻译文献

直流电动机闭环控制系统毕业论文中英文资料外文翻译文献

直流电动机闭环控制系统中英文资料外文翻译文献DC Motor Closed Loop Control SystemOne of the most fundamental concepts in the area of advanced manufacturing technologies is numerical control (NC).Prior to the advent of NC, all machine tools were manual operated and controlled. Among the many limitations associated with manual control machine tools, perhaps none is more prominent than the limitation of operator skills. With manual control, the quality of the product is directly related to and limited to the skills of the operator . Numerical control represents the first major step away from human control of machine tools.Numerical control means the control of machine tools and other manufacturing systems though the use of prerecorded, written symbolic instructions. Rather than operating a machine tool, an NC technician writes a program that issues operational instructions to the machine tool, For a machine tool to be numerically controlled , it must be interfaced with a device for accepting and decoding the p2ogrammed instructions, known as a reader.Numerical control was developed to overcome the limitation of human operator , and it has done so . Numerical control machines are more accurate than manually operated machines , they can produce parts more uniformly , they are faster, and the long-run tooling costs are lower . The development of NC led to the development of several other innovations in manufacturing technology:Electrical discharge machining.Laser cutting.Electron beam welding.Numerical control has also made machine tools more versatile than their manually operated predecessors. An NC machine tool can automatically produce a wide variety of par4s , each involving an assortment of undertake the production of products that would not have been feasible from an economic perspective using manually controlled machine tools and processes.Like so many advanced technologies , NC was born in the laboratories of the Massachusetts Institute of Technology . The concept of NC was developed in the early 1950s with funding provided by the U.S Air Force .In its earliest stages , NC machines were able to make straight cuts efficiently and effectively.However ,curved paths were a problem because the machine tool had to be programmed to undertake a series of horizontal and vertical steps to produce a curve. The shorter is the straight lines making up the step ,the smoother is 4he curve . Each line segment in the steps had to be calculated.This problem led to the development in 1959 of the Automatically Programmed Tools (APT) language for NC that uses statements similar to English language to define the part geometry, describe the cutting tool configuration, and specify the necessary motions. The development of the APT language was a major step forward in the further development of NC technology. The original NC system were vastly different from those used punched paper , which was later to replaced by magnetic plastic tape .A tape reader was used to interpret the instructions written on the tape for the machine .Together, all /f this represented giant step forward in the control of machine tools . However ,there were a number of problems with NC at this point in its development.A major problem was the fragility of the punched paper tape medium . It was common for the paper containing the programmed instructions to break or tear during a machining process, This problem was exacerbated by the fact that each successive time a part was produced on a machine tool, the paper tape carrying the programmed instructions had to rerun thought the reader . If it was necessary to produce 100 copies of a given part , it was also necessary to run the paper tape thought the reader 100 separate times . Fragile paper tapes simply could not withstand the rigors of shop floor environment and this kind of repeated use.This led to the development of a special magnetic tape . Whereas the paper tape carried the programmed instructions as a series of holes punched in the tape , theThismost important of these was that it was difficult or impossible to change the instructions entered on the tape . To make even the most minor adjustments in a program of instructions, it was necessary to interrupt machining operations and make a new tape. It was also still necessary to run the tape thought the reader as many times as there were parts to be produced . Fortunately, computer technology become a reality and soon solved the problems of NC, associated with punched paper and plastic tape.The development of a concept known as numerical control (DNC) solve the paper and plastic tape problems associated with numerical control by simply eliminating tape as the medium for carrying the programmed instructions . In direct numerical control, machine tools are tied, via a data transmission link, to a host computer and fed to the machine tool as needed via the data transmission linkage. Direct numerical control represented a major step forward over punched tape and plastic tape. However ,it is subject to the same limitation as all technologies that depend on a host computer. When the host computer goes down , the machine tools also experience down time . This problem led to the development of computer numerical control.The development of the microprocessor allowed for the development of programmable logic controllers (PLC) and microcomputers . These two technologies allowed for the development of computer numerical control (CNC).With CNC , each machine tool has a PLC or a microcomputer that serves the same purpose. This allows programs to be input and stored at each individual machine tool. CNC solved the problems associated downtime of the host computer , but it introduced another problem known as data management . The same program might be loaded on ten different microcomputers with no communication among them. This problem is in the process of being solved by local area networks that connectDigital Signal ProcessorsThere are numerous situations where analog signals to be processed in many ways, like filtering and spectral analysis , Designing analog hardware to perform these functions is possible but has become less and practical, due to increased performance requirements, flexibility needs , and the need to cut down on development/testing time .It is in other words difficult pm design analog hardware analysis of signals.The act of sampling an signal into thehat are specialised for embedded signal processing operations , and such a processor is called a DSP, which stands for Digital Signal Processor . Today there are hundreds of DSP families from as many manufacturers, each one designed for a particular price/performance/usage group. Many of the largestmanufacturers, like Texas Instruments and Motorola, offer both specialised DSP‟s for certain fields like motor-control or modems ,and general high-performance DSP‟s that can perform broad ranges of processing tasks. Development kits an` software are also available , and there are companies making software development tools for DSP‟s that allows the programmer to implement complex processing algorithms using simple “dr ag …n‟ drop” methodologies.DSP‟s more or less fall into two categories depending on the underlying architecture-fixed-point and floating-point. The fixed-point devices generally operate on 16-bit words, while the floating-point devices operate on 32-40 bits floating-point words. Needless to say , the fixed-point devices are generally cheaper . Another important architectural difference is that fixed-point processors tend to have an accumulator architecture, with only one “general purpose” register , makin g them quite tricky to program and more importantly ,making C-compilers inherently inefficient. Floating-point DSP‟s behave more like common general-purpose CPU‟s ,with register-files.There are thousands of different DSP‟s on the market, and it is diffic ult task finding the most suitable DSP for a project. The best way is probably to set up a constraint and wishlist, and try to compare the processors from the biggest manufacturers against it.The “big four” manufacturers of DSPs: Texas Instruments, Motor ola, AT&T and Analog Devices.Digital-to-analog conversionIn the case of MPEG-Audio decoding , digital compressed data is fed into the DSP which performs the decoding , then the decoded samples have to be converted back into the analog domain , and the resulting signal fed an amplifier or similar audio equipment . This digital to analog conversion (DCA) is performed by a circuit with the same name & Different DCA‟s provide different performance and quality , as measured by THD (Total harmonic distortion ), number of bits, linearity , speed, filter characteristics and other things.The TMS320 family DQP of Texas InstrumentsThe TLS320family consists of fixed-point, floating-point, multiprocessor digital signal processors (D[Ps) , and foxed-point DSP controllers. TMS320 DSP have an architecture designed specifically for real-time signal processing . The‟ F/C240 is a number of the‟C2000DSP platform , and is optimized for control applications. The‟C24xseries of DSP controllers combines this real-time processing capability with controller peripherals to create an ideal solution for control system applications. The following characteristics make the TMS320 family the right choice for a wide range of processing applications:--- Very flexible instruction set--- Inherent operational flexibility---High-speed performance---Innovative parallel architecture---Cost effectivenessDevices within a generation of the TMS320 family have the same CPU structure but different on-chip memory and peripheral configurations. Spin-off devices use new combinations of On-chip memory and peripherals to satisfy a wide range of needs in the worldwide electronics market. By integrating memory and peripherals onto a single chip , TMS320 devices reduce system costs and save circuit board space.The 16-bit ,fixed-point DSP core of the …C24x devices provides analog designers a digital solution that does not sacrifice the precision and performance of their system performance can be enhanced through the use of advanced control algorithms for techniques such as adaptive control , Kalman filtering , and state control. The …C24x DSP controller offer reliability and programmability . Analog control systems, on the other hand ,are hardwired solutions and can experience performance degradation due to aging , component tolerance, and drift.The high-speed central processing unit (CPU) allows the digital designer to process algorithms in real time rather than approximate results with look-up tables. The instruction set of these DSP controllers, which incorporates both signal processing instructions and general-purpose control functions, coupled with the extensive development time and provides the same ease of use as traditional 8-and 16-bit microcontrollers. The instruction set also allows you to retain your software investment when moving from other general-purpose…C2xx generation ,source code compatible with the‟C2x generation , and upwardly source code compatible with the …C5x generation of DSPs from Texas Instruments.The …C24x architect ure is also well-suited for processing control signals. It uses a 16-bit word length along with 32-bit registers for storing intermediate results, and has two hardware shifters available to scale numbers independently of the CPU . Thiscombination minimizes quantization and truncation errors, and increases p2ocessing power for additional functions. Such functions might include a notch filter that could cancel mechanical resonances in a system or an estimation technique that could eliminate state sensors in a system.The …C24xDSP controllers take advantage of an set of peripheral functions that allow Texas Instruments to quickly configure various series members for different price/ performance points or for application optimization.This library of both digital and mixed-signal peripherals includes:---Timers---Serial communications ports (SCI,SPI)---Analog-to-digital converters(ADC)---Event manager---System protection, such as low-voltage and watchdog timerThe DSP controller peripheral library is continually growing and changing to suit the of tomorrow‟s embedded control marketplace.The TMS320F/C240 is the first standard device introduced in the ...24x series of DSP controllers. It sets the standard for a single-chip digital motor controller. The (240)can execute 20 MIPS. Almost all instructions are executed in a simple cycle of 50 ns . This high performance allows real-time execution of very comple8 control algorithms, such as adaptive control and Kalman filters. Very high sampling rates can also be used to minimize loop delays.The … 240 has the architectural features necessary for high-speed signal processing and digital control functions, and it has the peripherals needed to provide a single-chip solution for motor control applications. The …240 is manufactured using submicron CMOS technology, achieving a log power dissipation rating . Also included are several power-down modes for further power savings. Some applications that benefit from the advanced processing power of the …240 include:---Industrial motor drives---Power inverters and controllers---Automotive systems, such as electronic power steering , antilock brakes, and climate control---Appliance and HV AC blower/ compressor motor controls---Printers, copiers, and other office products---Tape drives, magnetic optical drives, and other mass storage products---Robotic and CNC milling machinesTo function as a system manager, a DSP must have robust on-chip I/O and other peripherals. The event manager of the …240 is unlike any o ther available on a DSP . This application-optimized peripheral unit , coupled with the high performance DSP core, enables the use of advanced control techniques for high-precision and high-efficiency full variable-speed control of all motor types. Include in the event manager are special pulse-width modulation (PWM) generation functions, such as a programmable dead-band function and a space vector PWM state machine for 3-phase motors that provides state-of-the-art maximum efficiency in the switching of power transistors.There independent up down timers, each with it‟s own compare register, support the generation of asymmetric (noncentered) as well as symmetric (centered) PWM waveforms.Open-Loop and Closed-Loop ControlOpen-loop Control SystemsThe word automatic implies that there is a certain amount of sophistication in the control system. By automatic, it generally means That the system is usually capable of adapting to a variety of operating conditions and is able to respond to a class of inputs satisfactorily . However , not any type of control system has the automatic feature. Usually , the automatic feature is achieved by feed.g the feedback structure, it is called an open-loop system , which is the simplest and most economical type of control system.inaccuracy lies in the fact that one may not know the exact characteristics of the further ,which has a definite bearing on the indoor temperature. This alco points to an important disadvantage of the performance of an open -loop control system, in that the system is not capable of adapting to variations in environmental conitions or to external disturbances. In the case of the furnace control, perhaps an experienced person can provide control for a certain desired temperature in the house; but id the doors or windows are opened or closed intermittently during the operating period, the final temperature inside the house will not be accurately regulated by the open-loop control.An electric washing machine is another typical example of an open-loop system , because the amount of wash time is entirely determined by the judgment and estimation of the human operator . A true automatic electric washing machine should have the meansof checking the cleanliness of the clothes continuously and turn itsedt off when the desired degised of cleanliness is reached.Closed-Loop Control SystemsWhat is missing in the open-loop control system for more accurate and more adaptable control is a link or feedback from the output to the input of the system . In order to obtain more accurate bontrol, the controlled signal c(t) must be fed back and compared with the reference input , and an actuating signal proportional to the difference of the output and the input must be sent through the system to correct the error. A system with one or more feedback pat(s like that just described is called a closed-loop system. human being are probably the most complex and sophisticated feedback control system in existence. A human being may be considered to be a control system with many inputs and outputs, capable of carrying out highly complex operations.To illustrate the human being as a feedback control system , let us consider that the objective is to reach for an object on aperform the task. The eyes serve as a sensing device which feeds back continuously the position of the hand . The distance between the hand and the object is the error , which is eventually brought to zero as the hand reacher the object. This is a typical example of closed-loop control. However , if one is told to reach for the object and then is blindolded, one can only reach toward the object by estimating its exact position. It isAs anther illustrative example of a closed-loop control system, shows the block diagram of the rudder control system ofThe basic alements and the bloca diagram of a closed-loop control system are shown in fig. In general , the configuration of a feedback control system may not be constrained to that of fig & . In complex systems there may be multitude of feedback loops and element blocks.直流电动机闭环控制系统数字控制机床常常重达上百吨,但却常常要求切削工具的定位精度达到0.002毫米。

电气系统可编程序控制器毕业论文中英文资料外文翻译文献

电气系统可编程序控制器毕业论文中英文资料外文翻译文献

电气系统可编程序控制器中英文资料外文翻译文献英文原文Programmable controller designed for electro-pneumatic systems This project deals with the study of electro-pneumatic systems and the programmable controller that provides an effective and easy way to control the sequence of the pneumatic actuators movement and the states of pneumatic system. The project of a specific controller for pneumatic applications join the study of automation design and the control processing of pneumatic systems with the electronic design based on microcontrollers to implement the resources of the controller.1.IntroductionThe automation systems that use electro-pneumatic technology are formed mainly by three kinds of elements: actuators or motors, sensors or buttons and control elements like valves. Nowadays, most of the control elements used to execute the logic of the system were substituted by the Programmable Logic Controller(PLC).Sensors and switches are plugged as inputs and the direct control valves for the actuators are plugged as outputs. An internal program executes all the logic necessary to the sequence of the movements, simulates other components like counter, timer and control the status of the system.With the use of the PLC the project wins agility, because it is possible to create and simulate the system as many times as needed. Therefore, time can be saved, risk of mistakes reduced and complexity can be increased using the same elements.A conventional PLC, that is possible to find on the market from many companies, offers many resources to control not only pneumatic systems, but all kinds of system that uses electrical components. The PLC can be very versatile and robust to be applied in many kinds of application in the industry or even security system and automation of buildings.Because of those characteristics, in some applications the PLC offers to much resources that are not even used to control the system, electro-pneumatic system is one of this kind of application. The use of PLC, especially for small size systems, can be very expensive for the automation project.An alternative in this case is to create a specific controller that can offer the exactly size and resources that the project needs[3,4].This can be made using microcontrollers as the base of thiscontroller.The controller, based on microcontroller, can be very specific and adapted to only one kind of machine or it can work as a generic controller that can be programmed as a usual PLC and work with logic that can be changed. All these characteristics depend on what is needed and how much experience the designer has with developing an electronic circuit and firmware for microcontroller. But the main advantage of design the controller with the microcontroller is that the designer has the total knowledge of his controller, which makes it possible to control the size of the controller, change the complexity and the application of it. It means that the project gets more independence from other companies, but at the same time the responsibility of the control of the system stays at the designer hands2.Electro-pneumatic systemOn automation system one can find three basic components mentioned before ,plus a logic circuit that controls the system. An adequate technique is needed to project the logic circuit and integrate all the necessary components to execute the sequence of movements properly.For a simple direct sequence of movement an intuitive method can be used[1,5],but for indirect or more complex sequences the intuition can generate a very complicated circuit and signal mistakes. It is necessary to use another method that can save time of the project, make a clean circuit, can eliminate occasional signal overlapping and redundant circuits.The presented method is called step-by-step or algorithmic [1,5], it is valid for pneumatic and electro-pneumatic systems and it was used as a base in this work. The method consists of designing the systems based on standard circuits made for each change on the state of the actuators, these changes are called steps.Fig.1.Standard circuit for the pneumatic system.Fig.2.Standard circuit for the electro-pneumatic system.The first part is to design those kinds of standard circuits for each step, the next task is to link the standard circuits and the last part to connect the control element that receive signals from sensors, switches and the previous movement and give the air or electricity to the supply lines of each step. In Figs.1 and 2 the standard circuits are drawn for pneumatic and electro-pneumatic system [8].It is possible to see the relations with the previous and the next steps.3. The method applied inside the controllerThe result of the method presented before is a sequence of movements of the actuator that is well defined by steps. It means that each change on the position of the actuators is a new state of the system and the transition between states is called step.The standard circuit described before helps the designer to define the states of the systems and to define the condition to each change between the states. In the end of the design, the system is defined by a sequence that never chances and states that have the inputs and the outputs well defined. The inputs are the condition for the transition and the outputs are the result of the transition.All the configuration of those steps stays inside of the microcontroller and is executed the same way it was designed. The sequences of strings are programmed inside the controller with 5 bytes; each string has the configuration of one step of the process. There are two bytes for the inputs, one byte for the outputs and two more for the other configurations and auxiliary functions of the step. After programming, this sequence of strings is saved inside of a non-volatile memory of the microcontroller, so they can be read and executed.The controller task is not to work in the same way as a conventional PLC, but the purpose of it is to be an example of a versatile controller that is design for an specific area. A conventional PLC process the control of the system using a cycle where it makes an image of the inputs, execute all the conditions defined by the configuration programmed inside, and thenupdate the state of the outputs. This controller works in a different way, where it read the configuration of the step, wait the condition of inputs to be satisfied, then update the state or the outputs and after that jump to the next step and start the process again.It can generate some limitations, as the fact that this controller cannot execute, inside the program, movements that must be repeated for some time, but this problem can be solved with some external logic components. Another limitation is that the controller cannot be applied on systems that have no sequence. These limitations are a characteristic of the system that must be analyzed for each application.4. Characteristics of the controllerThe controller is based on the MICROCHIP microcontroller PIC16F877 [6,7] with 40 pins, and it has all the resources needed for this project. It ha enough pins for all the components, serial communication implemented in circuit, EEPROM memory to save all the configuration of the system and the sequence of steps. For the execution of the main program, it offers complete resources as timers and interruptions.The list of resources of the controller was created to explore all the capacity of the microcontroller to make it as complete as possible. During the step, the program chooses how to use the resources reading the configuration string of the step. This string has two bytes for digital inputs, one used as a mask and the other one used as a value expected. One byte is used to configure the outputs value. One bytes more is used for the internal timer, the analog input or time-out. The EEPROM memory inside is 256 bytes length that is enough to save the string of the steps, with this characteristic it is possible to save between 48 steps.The controller has also a display and some buttons that are used with an interactive menu to program the sequence of steps and other configurations.4.1.Interaction componentsFor the real application the controller must have some elements to interact with the final user and to offer a complete monitoring of the system resources that are available to the designer while creating the logic control of the pneumatic system:.Interactive mode of work; function available on the main program for didactic purposes, the user gives the signal to execute the step..LCD display, which shows the status of the system, values of inputs, outputs, timer and statistics of the sequence execution..Beep to give important alerts, stop, start and emergency..Leds to show power on and others to show the state of inputs and outputs.4.2. SecurityTo make the final application works property, a correct configuration to execute the steps in the right way is needed, but more then that it must offer solutions in case of bad functioning or problems in the execution of the sequence. The controller offers the possibility to configure two internal virtual circuits that work in parallel to the principal. These two circuits can be used as emergency or reset buttons and can return the system to a certain state at any time[2]. There are two inputs that work with interruption to get an immediate access to these functions. It is possible to configure the position, the buttons and the value of time-out of the system.er interfaceThe sequence of strings can be programmed using the interface elements of the controller. A computer interface can also be used to generate the user program easily. With a good documentation the final user can use the interface to configure the strings of bytes that define the steps of the sequence. But it is possible to create a program with visual resources that works as a translator to the user,it changes his work to the values that the controller understands.To implement the communication between the computer interface and the controller a simple protocol with check sum and number of bytes is the minimum requirements to guarantee the integrity of the data.4.4. FirmwareThe main loop works by reading the strings of the steps from the EEPROM memory that has all the information about the steps.In each step, the status of the system is saved on the memory and it is shown on the display too. Depending of the user configuration, it can use the interruption to work with the emergency circuit or time-out to keep the system safety. A block diagram of micro controller main program is presented.5.Example of electro-pneumatic systemThe system is not a representation of a specific machine, but it is made with some common movements and components found in a real one. The system is composed of four actuators. The actuators A,B and C are double acting and D-single acting. Actuator A advances and stays in specified position till the end of the cycle, it could work fixing an object to the next action for example(Fig.3), it is the first step. When A reaches the end position, actuator C starts his work together with B, making as many cycles as possible during the advancing of B. It depends on how fast actuator B is advancing; the speed is regulated by a flowing control valve. It was the second step. B and C are examples of actuators working together, while B pushes an objectslowly, C repeats. its work for some time.Fig.3.Time diagram of A,B,C and D actuators.When B reaches the final position, C stops immediately its cycle and comes back to the initial position. The actuator D is a single acting one with spring return and works together with the back of C, it is the third step. D works making very fast forward and backward movement, just one time. Its backward movement is the fourth step. D could be a tool to make a hole on the object.When D reaches the initial position, A and B return too, it is the fifth step.Fig.4 shows the first part of the designing process where all the movements of each step should be defined [2]. (A+)means that the actuator A moves to the advanced position and (A . )to the initial position. The movements that happen at the same time are joined together in the same step. The system has five steps.Fig.4.Step sequence of A,B,C and D actuators.These two representations of the system(Figs.3 and 4) together are enough to describe correctly all the sequence. With them is possible to design the whole control circuit with the necessary logic components. But till this time, it is not a complete system, because it is missing some auxiliary elements that are not included in this draws because they work in parallel with the main sequence.These auxiliary elements give more function to the circuit and are very important to the final application; the most important of them is the parallel circuit linked with all the others steps. That circuit should be able to stop the sequence at any time and change the state of the actuators to a specific position. This kind of circuit can be used as a reset or emergency buttons.The next Figs.5 and 6 show the result of using the method without the controller. Thesepictures are the electric diagram of the control circuit of the example, including sensors, buttons and the coils of the electrical valves.Fig.5.Electric diagram of the example.Fig.6.Electric diagram of the example.The auxiliary elements are included, like the automatic/manual switcher that permit a continuous work and the two start buttons that make the operator of a machine use their two hands to start the process, reducing the risk of accidents.6. Changing the example to a user programIn the previous chapter, the electro-pneumatic circuits were presented, used to begin thestudy of the requires to control a system that work with steps and must offer all the functional elements to be used in a real application. But, as explained above, using a PLC or this specific controller, the control becomes easier and the complexity can be increase also.It shows a resume of the elements that are necessary to control the presented example.With the time diagram, the step sequence and the elements of the system described in Figs.3 and 4 it is possible to create the configuration of the steps that can be sent to the controller.While using a conventional PLC, the user should pay attention to the logic of the circuit when drawing the electric diagram on the interface (Figs.5and 6), using the programmable controller, describe in this work, the user must know only the concept of the method and program only the configuration of each step.It means that, with a conventional PLC, the user must draw the relation between the lines and the draw makes it hard to differentiate the steps of the sequence. Normally, one needs to execute a simulation on the interface to find mistakes on the logic.The new programming allows that the configuration of the steps be separated, like described by the method. The sequence is defined by itself and the steps are described only by the inputs and outputs for each step.The structure of the configuration follows the order:1-byte: features of the step;2-byte: for the inputs;3-byte: value expected on the inputs;4-byte: value for the outputs;5-byte: value for the extra function.Fig.7.Actuators A and B, and sensors.Fig.8.Actuators C and D, and sensors.Table 5 shows how the user program is saved inside the controller, this is the program that describes the control of the example shown before.The sequence can be defined by 25 bytes. These bytes can be divided in five strings with 5 bytes each that define each step of the sequence (Figs.7 and 8).7. ConclusionThe controller developed for this work shows that it is possible to create a very useful programmable controller based on microcontroller. External memories or external timers were not used in case to explore the resources that the microcontroller offers inside. Outside the microcontroller, there are only components to implement the outputs, inputs, analog input, display for the interface and the serial communication.Using only the internal memory, it is possible to control a pneumatic system that has a sequence with 48 steps if all the resources for all steps are used, but it is possible to reach sixty steps in the case of a simpler system.The programming of the controller does not use PLC languages, but a configuration that is simple and intuitive. With electro-pneumatic system, the programming follows the same technique that was used before to design the system, but here the designer works directly with the states or steps of the system.With a very simple machine language the designer can define all the configuration of the step using four or five bytes. It depends only on his experience to use all the resources of the controller.The controller task is not to work in the same way as a commercial PLC but the purpose of it is to be an example of a versatile controller that is designed for a specific area. Because of that, it is not possible to say which one works better; the system made with microcontroller is an alternative that works in a simple way.References[1]E.Nelli Silva,Fluid-mechanics systems Manual, Escola Politecnica USP,2002(in Portuguese).[2]J.Swider,Control and Automation of Technological Process and Mechatronic systems,Silesian University Publishing Company,Gli-wice,2002(redaction in Polish).[3]J.Swider, G.Wszolek, W.Carvalho. Example of the system prepared to be controlled by the controller based on microcontroller,in:12 International Scientific Conference—Achievements in Mechanical and MaterialsEngineering,Gliwice-Zakopane,Poland,2003,pp.965-970.[4]J.Swider,G.Wszolek,W.Carvalho, Controller based on microcontroller designed to execute the logic control of pneumatic systems, in:12International Scientific Conference—Achievements in Mechanical and Materials Engineering,Gliwice-Zakopane,Poland,2003,pp. 959–964.[5]J.Swider,G.Wszoek, The methodical collection of laboratory and project tasks of technological process control in Pneumatic and Electro-pneumatic Systems with Logical PLC Control, Silesian University Publishing Company,Gliwice,2003.[6]PIC 16f87xDatasheet.MICROCHIP,2001.[7]Application notes AN587 and AN546.MICROCHIP,1997.[8]Fundamental of electro-pneumatic—FESTODidactic,2000.中文翻译应用于电气系统的可编程序控制器摘要此项目主要是研究电气系统以及简单有效的控制气流发动机的程序和气流系统的状态。

液压挖掘机的半自动控制系统毕业论文中英文资料对照外文翻译文献综述

液压挖掘机的半自动控制系统毕业论文中英文资料对照外文翻译文献综述

液压挖掘机的半自动控制系统中英文资料对照外文翻译文献综述翻译部分1.英文原文Semi-automatic control system for hydraulic shovelHirokazu Araya),Masayuki KagoshimaMechanical Engineering Research Laboratory,Kobe Steel,Ltd.,Nishi-ku,Kobe Hyogo 651 2271,JapanAccepted 27 June 2000AbstractA semi-automatic control system for a hydraulic shovel has been ing this system,unskilled operators canoperate a hydraulic shovel easily and accurately.A mathematical control model of a hydraulic shovel with a controller wasconstructed and a control algorithm was developed by simulation.This algorithm was applied to a hydraulic shovel and itseffectiveness was evaluated.High control accuracy and high-stability performance were achieved by feedback plusfeedforward control,nonlinear compensation,state feedback and gainscheduling according to the attitude.q 2001 ElsevierScience B.V.All rights reserved.Keywords: Construction machinery;Hydraulic shovel;Feedforward;State feedback;Operation1.IntroductionA hydraulic shovel is a construction machinery that can be regarded as a large articulated robot. Digging and loading operations using this machine require a high level of skill,and cause considerable fatigue even in skilled operators.On the other hand, operators grow older,and the number of skilled operators has thus decreased.The situation calls for hydraulic shovels,which can be operated easily by any person w1 –5x. The reasons why hydraulic shovel requires a high level of skill are as follows.1.More than two levers must be operated simulta-neously and adjusted well in such operations.2.The direction of lever operations is different from that of a shovel’s attachment movement. For example,in level crowding by a hydraulic shovel,we must operate three levers ?arm,boom, bucket. simultaneously to move the top of a bucket along a level surface ?Fig.1..In this case,the lever operation indicates the direction of the actuator,but this direction differs from the working direction. If an operator use only one lever and other free-doms are operated automatically,the operation be-comes veryeasily.We call this system a semi-auto-matic control system.When we develop this semi-automatic control system,these two technical problems must be solved.1.We must use ordinary control valves for auto-matic control.2.We must compensate dynamic characteristics of a hydraulic shovel to improve the precision of control.Fig.1.Level crowding of an excavator and frame model of an excavator. We have developed a control algorithm to solve these technical problemsand confirm the effect of this control algorithm by experiments with actual hydraulic ing this control algorithm,we have completed a semi-automatic control system for hydraulic shovels.We then report these items.2.Hydraulic shovel modelTo study control algorithms,we have to analyze numerical models of a hydraulic shovel.The hy- draulic shovel,whose boom,arm,and bucket joints are hydraulically driven,is modeled as shown in Fig.2.The details of the model are described in the following.2.1.Dynamic model [6]Supposing that each attachment is a solid body, from Lagrange’s equations of motion,the following expressions are obtained:K 3 s m 3 1 g3g;and g s gravitational acceleration. u is the joint angle,t is the supply torque the attachment length,1 g iis the distance between the fulcrum and the center of gravity,m iis the mass of the attachment,I iis the moment of inertia around the center of gravity ?subscripts i s 1–3,mean boom, arm,and bucket,respectively..2.2.Hydraulic modelEach joint is driven by a hydraulic cylinder whose flow is controlled by a spool valve,as shown in Fig.3.We can assume the following:1.The open area of a valve is proportional to the spool displacement.2.There is no oil leak.3.No pressure drop occurs when oil flows throughpiping.H.Araya,M.Kagoshimar Automation in Construction 10 (2001) 477–486 479Fig.2.Model of hydraulic shovel.4.The effective sectional area of the cylinder is the same on both the head and the rod sides. In this problem,for each joint,we have the followingequation from the pressure flow character-stics of the cylinder:时;where,A is effective cross-sectional area of cylin-der;h i s cylinder length;X is spool displacement;Ps i s supply pressure;P1 is cylinder head-side pres-sure;P 2 i s cylinder rod-side pressure;Vi s oilvol-ume in thecylinder andpiping;B is spoolwidth; gsoildensity;KsbulkFig.3.Model of hydraulic cylinder and valve.modulus of oil;and cs flow coefficient.2.3.Link relationsIn the model shown in Fig.1,the relation be-tween the cylinder length change rate and the attach-ment rotational angular velocity is given as follows:?1. boom2.4.Torque relations From the link relations of Section 2.3,the supply torque t is given as follows,taking cylinder friction I into consideration: Where,C ciis the viscous friction coefficient and Fi is kinetic frictional force of a cylinder2.5.Response characteristics of the spool Spool action has a great effect on control charac-teristics.Thus,we are assuming that the spool hasthe following first-order lag against the reference input.iis the reference input of spool dis- placement and Ts piis a time constant.3.Angle control systemAs shown in Fig.4,the angle u is basically controlled to follow the reference angle ug by posi-tion feedback.In order to obtain more accuratecontrol,nonlinear compensation and state feedback are added to theposition feedback.We will discuss details of these algorithms as follows. 3.1.Nonlinear compensationIn the ordinary automatic control systems,new control devices such as servo valves are used.In our semi-automatic system,in order to realize the coexistence of manual and automatic operations,we must use the main control valves,which are used in manual operation.In these valves,the relation between spool displacement and open area is nonlinear. Then,in automatic operation,using this relation,the spool displacement is inversely calculated from the required open area,and the nonlinearity is compen- sated ?Fig.5..Fig.4.Block diagram of control system ?u..H.Araya,M.Kagoshimar Automation in Construction 10 (2001) 477–486 481Fig.5.Nonlinear compensation.3.2.State feedbackBased on the model discussed in Section 2,if thedynamic characteristics forboom angle control are linearized in the vicinity of a certain standard condition ?spool displacement X10,cylinder differential pressure P,and boom angle u.,the closed-looptransfer function can be expressed byThis system has a comparatively small coefficient a1so the response is oscillatory.For instance,if in our large SK-16 hydraulic shovel,X 10is 0,the coefficients are given as a s 2.7=102.Addingthe accelerationfeedback of gain Ka,to this ?the upper loop in Fig.4.,the closed loop transfer function is given as Adding this factor,the coefficient of s2 becomes larger,thus,the system becomes stable.In this way,acceleration feedback is effective in improving the response characteristics.However,it is generally difficult to detect acceleration accurately.To overcome this difficulty,cylinder force feedback was applied instead of acceleration feedback ?the lower loop in Fig.4..In this case,cylinder force is calculated from detected cylinder pressure and filtered in its lower-frequency portion w 7,8x.This is called pressure feedback.4.Servo control systemWhen one joint is manually operated and another joint is controlled automatically to follow the manual operation,a servo control system must be required. For example,as shown in Fig.6,in the level crowding control,the boom is controlled to keep the arm end height Z ?calculated from u and u .to reference Zr.In order to obtain more accurate control,the following control actions are introduced.482H.Araya,M.Kagoshimar Automation in Construction 10 (2001) 477–486Fig.6.Block diagram of control system ?Z..4.1.Feedforward control Calculating Z from Fig.1,we obtain Differentiating both sides of Eq.?8. with respect to time,we have the following relation, The first term of the right-hand side can be taken as the expression ?feedback portion. to convert Z˙ to u˙,and the second term of the right-hand side is the expression ?feedforward portion. to calculate how much u should be changed when u is changed 1 2 manually.Actually,u˙ is determined using the difference2 value of Du.To optimizehe feedforward rate,feedforward gain K ffis tunned. There may be a method to detect and use the arm operating-lever condition ?i.e.angle. instead of arm angular velocity,since the arm is driven at an angular velocity nearly proportional to this lever condi-tion.4.2.Adapti?e gain scheduling according to the attitude In articulated machines like hydraulic shovels,dynamic characteristics are greatly susceptible to the attitude.Therefore,it is difficult to control the machine stably at all attitudes with constant gain.To solve this problem,the adaptive gain scheduling according to the attitude is multiplied in the feedbackloop ?Fig.6..As shown in Fig.7,the adaptive gain KZ or K u .is characterized as a function of two variables,u X and Z.u X 2 2means how the arm is extended,and Z means the height of the bucket.5.Simulation resultsThe level crowding control was simulated byapplying the control algorithm described in Section 4 to the hydraulic shovel model discussed in Section 2.In the simulation,our large SK-16 hydraulic shovel was employed..Fig.8 shows one of the results.Five seconds after the control started,load disturbanceH.Araya,M.Kagoshimar Automation in Construction 10 (2001) 477–486 483Fig.7.Gain scheduling according to the attitude. was applied stepwise.Fig.9shows the use of feedforward control can reduce control error.6.ConclusionsThis paper has shown that combining state feedback and feedforward controls makes it possible toaccurately control the hydraulic shovel,and also showed that nonlinear compensation makes it possible to use ordinary control valves for automatic controls.The use of these control techniques allows even unskilled operators to operate hydraulic shovels easily and accurately.We will apply these control techniques to other construction machinery such as crawler cranes,and improve the conventional construction machinery to the machines which can be operated easily byanyone.2. 中文译文液压挖掘机的半自动控制系统Hirokazu Araya ,Masayuki Kagoshima 日本机械工程研究实验室Kobe Steel, Ltd., Nishi-ku, Kobe Hyogo 651 2271,2000年7月27日摘要开发出了一种应用于液压挖掘机的半自动控制系统。

智能控制系统毕业论文中英文资料对照外文翻译文献

智能控制系统毕业论文中英文资料对照外文翻译文献
mechanical device directly to the monitored parameters to regulate and control, in the single-chip microcomputer as the core of the control system, the control parameters and controlled parameters are not directly change, but the control parameter is transformed into a digital signal input to the microcontroller, the microcontroller according to its output signal to control the
controlled object, as intelligent load monitoring test, is the use of single-chip I / O port output signal of relay control, then the load to control or monitor, thus similar to any one single chip control system structure, often simplified to input part, an output part and an electronic control unit ( ECU )
information, which can more effectively assist the security personnel to deal with the crisis, and minimize the damage and loss, it has great practical significance, some risk homework, or artificial unable to complete the operation, can be used to realize intelligent device, which solves a lot of artificial can not solve the problem, I think, with the development of the society, intelligent load in all aspects of social life play an important reuse.
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控制系统基础论文中英文资料外文翻译文献文献翻译原文:Numerical ControlOne of the most fundamental concepts in the area of advanced manufacturing technologies is numerical control (NC).Prior to the advent of NC, all machine tools were manual operated and controlled. Among the many limitations associated with manual control machine tools, perhaps none is more prominent than the limitation of operator skills. With manual control, the quality of the product is directly related to and limited to the skills of the operator . Numerical control represents the first major step away from human control of machine tools.Numerical control means the control of machine tools and other manufacturing systems though the use of prerecorded, written symbolic instructions. Rather than operating a machine tool, an NC technician writes a program that issues operational instructions to the machine tool, For a machine tool to be numerically controlled , it must be interfaced with a device for accepting and decoding the p2ogrammed instructions, known as a reader.Numerical control was developed to overcome the limitation of human operator , and it has done so . Numerical control machines are more accurate than manually operated machines , they can produce parts more uniformly , they are faster, and the long-run tooling costs are lower . The development of NC led to the development of several other innovations in manufacturing technology:1.Electrical discharge machining.ser cutting.3.Electron beam welding.Numerical control has also made machine tools more versatile than their manually operated predecessors. An NC machine tool can automatically produce a wide variety of par 4s , each involving an assortment of undertake the production of products that would not have been feasible from an economic perspective using manually controlled machine tools and processes.Like so many advanced technologies , NC was born in the laboratories of the Massachusetts Institute of Technology . The concept of NC was developed in the early 1950s with funding provided by the U.S Air Force .In its earliest stages , NC machines were able to make straight cuts efficiently and effectively.However ,curved paths were a problem because the machine tool had to be programmed to undertake a series of horizontal and vertical steps to produce a curve. The shorter is the straight lines making up the step ,the smoother is the curve . Each line segment in the steps had to be calculated.This problem led to the development in 1959 of the Automatically Programmed Tools (APT) language for NC that uses statements similar to English language to define the part geometry, describe the cutting tool configuration, and specify the necessary motions. The development of the APT language was a major step forward in the further development of NC technology. The original NC system were vastly different from those used punched paper , which was later to replaced by magnetic plastic tape .A tape reader was used to interpret the instructions written on the tape for the machine .Together, all of this represented giant step forward in the control of machine tools . However ,there were a number of problems with NC at this point in its development.A major problem was the fragility of the punched paper tape medium . It was common for the paper containing the programmed instructions to break or tear during a machining process, This problem was exacerbated by the fact that each successive time a part was produced on a machine tool, the paper tape carrying the programmed instructions had to rerun thought the reader . If it was necessary to produce 100 copies of a given part , it was also necessary to run the paper tape thought the reader 100 separate times . Fragile paper tapes simply could not withstand the rigors of shop floorenvironment and this kind of repeated use.This led to the development of a special magnetic tape . Whereas the paper tape carried the programmed instructions as a series of holes punched in the tape , theThis most mportant of these was that it was difficult or impossible to change the instructions entered on the tape . To make even the most minor adjustments in a program of instructions, it was necessary to interrupt machining operations and make a new tape. It was also still necessary to run the tape thought the reader as many times as there were parts to be produced . Fortunately, computer technology become a reality and soon solved the problems of NC, associated with punched paper and plastic tape.The development of a concept known as numerical control (DNC) solve the paper and plastic tape problems associated with numerical control by simply eliminating tape as the medium for carrying the programmed instructions . In direct numerical control, machine tools are tied, via a data transmission link, to a host computer and fed to the machine tool as needed via the data transmission linkage. Direct numerical control represented a major step forward over punched tape and plastic tape. However ,it is subject to the same limitation as all technologies that depend on a host computer. When the host computer goes down , the machine tools also experience down time . This problem led to the development of computer numerical control.The evelopment of the microprocessor allowed for the development of programmable logic controllers (PLC) and microcomputers . These two technologies allowed for the development of computer numerical control (CNC).With CNC , each machine tool has a PLC or a microcomputer that serves the same purpose. This allows programs to be input and stored at each individual machine tool. CNC solved the problems associated downtime of the host computer , but it introduced another problem known as data management . The same program might be loaded on ten different microcomputers with no communication among them. This problem is in the process of being solved by local area networks that connectDigital ignal Processors.There are numerous situations where analog signals to be processed in manyways, like filtering and spectral analysis , Designing analog hardware to perform these functions is possible but has become less and practical, due to increased performance requirements, flexibility needs , and the need to cut down on development/testing time .It is in other words difficult pm design analog hardware analysis of signals.The act of sampling an signal into thehat are specialised for embedded signal processing operations , and such a processor is called a DSP, which stands for Digital Signal Processor . Today there are hundreds of DSP families from as many manufacturers, each one designed for a particular price/performance/usage group. Many of the largest manufacturers, like Texas Instruments and Motorola, offer both specialised DSP‟s for certain fields like motor-control or modems ,and general high-performance SP‟s that can erform broad ranges of processing tasks. Development kits an software are also available , and there are companies making software development tools for DSP‟s that allows the programmer to implement complex processing algorithms using simple “drag …n‟ drop” methodologies.DSP‟s more or less fall into two categories depending on the underlying architecture-fixed-point and floating-point. The fixed-point devices generally operate on 16-bit words, while the floating-point devices operate on 32-40 bits floating-point words. Needless to say , the fixed-point devices are generally cheaper . Another important architectural difference is that fixed-point processors tend to have an accumulator architecture, with only one “general purpose” register , making them quite tricky to program and more importantly ,making C-compilers inherently inefficient. Floating-point DSP‟s behave more like common general-purpose CPU‟s ,with register-files.There are thousands of different DSP‟s on the market, and it is difficult task finding the most suitable DSP for a project. The best way is probably to set up a constraint and wishlist, and try to compare the processors from the biggest manufacturers against it.The “big four” manufacturers of DSP‟s: Texas Instruments, Motorola, AT&T and Analog Devices.Digital-to-analog conversionIn the case of MPEG-Audio decoding , digital compressed data is fed into the DSP which performs the decoding , then the decoded samples have to be converted back into the analog domain , and the resulting signal fed an amplifier or similar audio equipment . This digital to analog conversion (DCA) is performed by a circuit with the same name & Different DCA‟s provide different performance and quality , as measured by THD (Total harmonic distortion ), number of bits, linearity , speed, filter characteristics and other things.The TMS320 family DQP of Texas InstrumentsThe TLS320family consists of fixed-point, floating-point, multiprocessor digital signal processors (DSP‟s) , and foxed-point DSP controllers. TMS320 DSP have an architecture designed specifically for real-time signal processing . The F/C240 is a number of the‟C2000DSP platform , and is optimized for control applications. The C24x series of DSP controllers combines this real-time processing capability with controller peripherals to create an ideal solution for control system applications. The following characteristics make the TMS320 family the right choice for a wide range of processing applications:--- Very flexible instruction set--- Inherent operational flexibility---High-speed performance---Innovative parallel architecture---Cost effectivenessDevices within a generation of the TMS320 family have the same CPU structure but different on-chip memory and peripheral configurations. Spin-off devices use new combinations of On-chip memory and peripherals to satisfy a wide range of needs in the worldwide electronics market. By integrating memory and peripherals onto a single chip , TMS320 devices reduce system costs and save circuit board space.The 16-bit ,fixed-point DSP core of the C24x devices provides analog designers a digital solution that does not sacrifice the precision and performance of their system performance can be enhanced through the use of advanced control algorithms for techniques such as adaptive control , Kalman filtering , and state control. The C24xDSP controller offer reliability and programmability . Analog control systems, on the other hand ,are hardwired solutions and can experience performance degradation due to aging , component tolerance, and drift.The high-speed central processing unit (CPU) allows the digital designer to process algorithms in real time rather than approximate results with look-up tables. The instruction set of these DSP controllers, which incorporates both signal processing instructions and general-purpose control functions, coupled with the extensive development time and provides the same ease of use as traditional 8-and 16-bit microcontrollers. The instruction set also allows you to retain your software investment when moving from other general-purpose C2xx generation ,source code compatible with the C2x generation , and upwardly source code compatible with the C5x generation of DSPs from Texas Instruments.The C24x architecture is also well-suited for processing control signals. It uses a 16-bit word length along with 32-bit registers for storing intermediate results, and has two hardware shifters available to scale numbers independently of the CPU . This combination minimizes quantization and truncation errors, and increases p2ocessing power for additional functions. Such functions might include a notch filter that could cancel mechanical resonances in a system or an estimation technique that could eliminate state sensors in a system.The C24xDSP controllers take advantage of an set of peripheral functions that allow Texas Instruments to quickly configure various series members for different price/ performance points or for application optimization.This library of both digital and mixed-signal peripherals includes:---Timers---Serial communications ports (SCI,SPI)---Analog-to-digital converters(ADC)---Event manager---System protection, such as low-voltage and watchdog timerThe DSP controller peripheral library is continually growing and changing to suit the of tomorrow‟s e mbedded control marketplace.The TMS320F/C240 is the first standard device introduced in the …24x series of DSP controllers. It sets the standard for a single-chip digital motor controller. The 240 can execute 20 MIPS. Almost all instructions are executed in a simple cycle of 50 ns . This high performance allows real-time execution of very comple8 control algorithms, such as adaptive control and Kalman filters. Very high sampling rates can also be used to minimize loop delays.The 240 has the architectural features necessary for high-speed signal processing and digital control functions, and it has the peripherals needed to provide a single-chip solution for motor control applications. The 240 is manufactured using submicron CMOS technology, achieving a log power dissipation rating . Also included are several power-down modes for further power savings. Some applications that benefit from the advanced processing power of the 240 include:---Industrial motor drives---Power inverters and controllers---Automotive systems, such as electronic power steering , antilock brakes, and climate control---Appliance and HV AC blower/ compressor motor controls---Printers, copiers, and other office products---Tape drives, magnetic optical drives, and other mass storage products---Robotic and CNC milling machinesTo function as a system manager, a DSP must have robust on-chip I/O and other peripherals. The event manager of the 240 is unlike any other available on a DSP . This application-optimized peripheral unit , coupled with the high performance DSP core, enables the use of advanced control techniques for high-precision and high-efficiency full variable-speed control of all motor types. Include in the event manager are special pulse-width modulation (PWM) generation functions, such as a programmable dead-band function and a space vector PWM state machine for 3-phase motors that provides state-of-the-art maximum efficiency in the switching of power transistors.There independent up down timers, each with it‟s own compare register, supportthe generation of asymmetric (noncentered) as well as symmetric (centered) PWM waveforms.Open-Loop and Closed-Loop ControlOpen-loop Control SystemsThe word automatic implies that there is a certain amount of sophistication in the control system. By automatic, it generally means That the system is usually capable of adapting to a variety of operating conditions and is able to respond to a class of inputs satisfactorily . However , not any type of control system has the automatic feature. Usually , the automatic feature is achieved by feed.The feedback structure, it is called an open-loop system , which is the simplest and most economical type of control system.inaccuracy lies in the fact that one may not know the exact characteristics of the further ,which has a definite bearing on the indoor temperature. This alco points to an important disadvantage of the performance of an open -loop control system, in that the system is not capable of adapting to variations in environmental conitions or to external disturbances. In the case of the furnace control, perhaps an experienced person can provide control for a certain desired temperature in the house; but id the doors or windows are opened or closed intermittently during the operating period, the final temperature inside the house will not be accurately regulated by the open-loop control.An electric washing machine is another typical example of an open-loop system , because the amount of wash time is entirely determined by the judgment and estimation of the human operator . A true automatic electric washing machine should have the means of checking the cleanliness of the clothes continuously and turn itsedt off when the desired degised of cleanliness is reached.Closed-Loop Control SystemsWhat is missing in the open-loop control system for more accurate and more adaptable control is a link or feedback from the output to the input of the system . In order to obtain more accurate bontrol, the controlled signal c(t) must be fed back and compared with the reference input , and an actuating signal proportional to the difference of the output and the input must be sent through the system to correct theerror. A system with one or more feedback pats like that just described is called a closed-loop system. human being are probably the most complex and sophisticated feedback control system in existence. A human being may be considered to be a control system with many inputs and outputs, capable of carrying out highly complex operations.To illustrate the human being as a feedback control system , let us consider that the objective is to reach for an object on aperform the task. The eyes serve as a sensing device which feeds back continuously the position of the hand . The distance between the hand and the object is the error , which is eventually brought to zero as the hand reacher the object. This is a typical example of closed-loop control. However , if one is told to reach for the object and then is blindolded, one can only reach toward the object by estimating its exact position. It is As anther illustrative example of a closed-loop control system, shows the block diagram of the rudder control system of The basic alements and the bloca diagram of a closed-loop control system are shown in fig. In general , the configuration of a feedback control system may not be constrained to that of fig & . In complex systems there may be multitude of feedback loops and element blocks.译文:控制系统基础数字控制机床常常重达上百吨,但却常常要求切削工具的定位精度达到0.002毫米。

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