超声波测距系统外文文献翻译
毕业设计论文 外文文献翻译 超声波测距 中英文对照
毕业设计论文外文文献翻译超声波测距中英文对照The Circuit Design of UltrasonicRanging System超声波测距系统的电路设计Ultrasonic Distance Meter超声波测距仪姓名:专业: 测控技术与仪器学号: 2007071071指导教师姓名,职称,:The Circuit Design of Ultrasonic Ranging SystemThis article described the three directions (before, left, right) ultrasonic ranging system is to understand the front of the robot, left and right environment to provide a movement away from the information. (Similar to GPS Positioning System)A principle of ultrasonic distance measurement1, the principle of piezoelectric ultrasonic generatorPiezoelectric ultrasonic generator is the use of piezoelectriccrystal resonators to work. Ultrasonic generator, the internal structure as shown in Figure 1, it has two piezoelectric chip and a resonance plate. When it's two plus pulse signal, the frequency equal to the intrinsic piezoelectric oscillation frequency chip, the chip will happen piezoelectric resonance, and promote the development of plate vibrationresonance, ultrasound is generated. Conversely, if the two are notinter-electrode voltage, when the board received ultrasonic resonance,it will be for vibration suppression of piezoelectric chip, the mechanical energy is converted to electrical signals, then it becomes the ultrasonic receiver.2, the principle of ultrasonic distance measurementUltrasonic transmitter in a direction to launch ultrasound, in the moment to launch the beginning of time at the same time, the spread of ultrasound in the air, obstacles on his way to return immediately, the ultrasonic reflected wave received by the receiver immediately stop the clock. Ultrasound in the air as the propagation velocity of 340m / s, according to the timer records the time t, we can calculate the distance between the launch distance barrier (s), that is: s = 340t / 2 Ultrasonic Ranging System for the Second Circuit DesignSystem is characterized by single-chip microcomputer to control the use of ultrasonic transmitter and ultrasonic receiver since the launch from time to time, single-chip selection of 8751, economic-to-use, and the chip has 4K of ROM, to facilitate programming. Circuit schematic diagram shown in Figure 2. Draw only the front range of the circuit wiring diagram, left and right in front of Ranging circuits and the same circuit, it is omitted.1,40 kHz ultrasonic pulse generated with the launchRanging system using the ultrasonic sensor of piezoelectric ceramic sensors UCM40, its operating voltage of the pulse signal is 40kHz, whichby the single-chip implementation of the following procedures to generate.puzel: mov 14h, # 12h; ultrasonic firing continued 200mshere: cpl p1.0; output 40kHz square wavenop;nop;nop;djnz 14h, here;retRanging in front of single-chip termination circuit P1.0 input port, single chip implementation of the above procedure, the P1.0 port in a40kHz pulse output signal, after amplification transistor T, the drive to launch the first ultrasonic UCM40T, issued 40kHz ultrasonic pulse, and the continued launch of 200ms. Ranging the right and the left side of the circuit, respectively, then input port P1.1 and P1.2, the working principle and circuit in front of the same location.2, reception and processing of ultrasonicUsed to receive the first launch of the first pair UCM40R, the ultrasonic pulse modulation signal into an alternating voltage, the op-amp amplification IC1A and after polarization IC1B to IC2. IC2 is locked loop with audio decoder chip LM567, internal voltage-controlledoscillator center frequency of f0 = 1/1.1R8C3, capacitor C4 determine their target bandwidth. R8-conditioning in the launch of the carrier frequency on the LM567 input signal is greater than 25mV, the outputfrom the high jump 8 feet into a low-level, as interrupt request signals to the single-chip processing.Ranging in front of single-chip termination circuit output port INT0 interrupt the highest priority, right or left location of the output circuit with output gate IC3A access INT1 port single-chip, whilesingle-chip P1.3 and P1. 4 received input IC3A, interrupted by the process to identify the source of inquiry to deal with, interruptpriority level for the first left right after. Part of the source codeis as follows:receive1: push pswpush accclr ex1; related external interrupt 1jnb p1.1, right; P1.1 pin to 0, ranging from right to interrupt service routine circuitjnb p1.2, left; P1.2 pin to 0, to the left ranging circuit interrupt service routinereturn: SETB EX1; open external interrupt 1pop accpop pswretiright: ...; right location entrance circuit interrupt serviceroutineAjmp Returnleft: ...; left Ranging entrance circuit interrupt service routineAjmp Return4, the calculation of ultrasonic propagation timeWhen you start firing at the same time start the single-chipcircuitry within the timer T0, the use of timer counting function records the time and the launch of ultrasonic reflected wave received time. When you receive the ultrasonic reflected wave, the receivercircuit outputs a negative jump in the end of INT0 or INT1 interrupt request generates a signal, single-chip microcomputer in response to external interrupt request, the implementation of the external interrupt service subroutine, read the time difference, calculating the distance . Some of its source code is as follows:RECEIVE0: PUSH PSWPUSH ACCCLR EX0; related external interrupt 0MOV R7, TH0; read the time valueMOV R6, TL0?CLR CMOV A, R6SUBB A, # 0BBH; calculate the time differenceMOV 31H, A; storage resultsMOV A, R7SUBB A, # 3CHMOV 30H, ASETB EX0; open external interrupt 0POP ACCPOP PSWRETIFourth, the ultrasonic ranging system software designSoftware is divided into two parts, the main program and interrupt service routine, shown in Figure 3 (a) (b) (c) below. Completion of the work of the main program is initialized, each sequence of ultrasonic transmitting and receiving control.Interrupt service routines from time to time to complete three ofthe rotation direction of ultrasonic launch, the main external interrupt service subroutine to read the value of completion time, distance calculation, the results of the output and so on.V. CONCLUSIONSRequired measuring range of 30cm ~ 200cm objects inside the plane to do a number of measurements found that the maximum error is 0.5cm, and good reproducibility. Single-chip design can be seen on the ultrasonic ranging system has a hardware structure is simple, reliable, small features such as measurement error. Therefore, it can be used not only for mobile robot can be used in other detection systems.Thoughts: As for why the receiver do not have the transistoramplifier circuit, because the magnification well, CX20106 integrated amplifier, but also with automatic gain control level, magnification to 76dB, the center frequency is 38k to 40k, is exactly resonant ultrasonic sensors frequency.超声波测距系统的电路设计本文所介绍的三方向(前、左、右)超声波测距系统，就是为机器人了解其前方、左侧和右侧的环境而提供一个运动距离信息。
超声波测距外文文献加中文翻译毕业设计
附录A 英文原文ULTASONIC RANGING IN AIRG. E. Rudashevski and A. A. GorbatovOne of the most important problems in instrumentation technology is the remote,contactless measurement of distances in the order of 0.2 to 10 m in air.Such a problem occurs,for instance,when measuring the relativethre edimensional position of separate machine members or structural units.Interesting possibilities for its solution are opened up by utilizing ultrasonic vibrations as an information carrier.The physical properties of air,in which the measurements are made,permit vibrations to be employed at frequencies up to 500 kHz for distances up to 0.5 m between a member and the transducer,or up to 60 kHz when ranging on obstacles located at distances up to 10 m.The problem of measuring distances in air is somewhat different from other problems in the a -pplication of ultrasound.Although the possibility of using acoustic ranging for this purpose has been known for a long time,and at first glance appears very simple,nevertheless at the present time there are only a small number of developments using this method that are suitable for practical purposes.The main difficulty here is in providing a reliable acoustic three-dimensional contact with the test object during severe changes in the air's characteristic.Practically all acoustic arrangements presently known for checking distances use a method of measuring the propagation time for certain information samples from the radiator to the reflecting member and back.The unmodulated acoustic(ultrasonic)vibrations radiated by a transducer are not in themselves a source of information.In order to transmit some informational communication that can then be selected at the receiving end after reflection from the test member,the radiated vibrations must be modulated.In this case the ultrasonic vibrations are the carrier of the information which lies in the modulation signal,i.e.,they are the means for establishing the spatial contact between the measuring instrument and the object being measured.This conclusion,however,does not mean that the analysis and selection of parameters for the carrier vibrations is of minor importance.On the contrary,the frequency of the carrier vibrations is linked in a very close manner with the coding method for the informational communication,with the passband of the receiving and radiating elements in the apparatus,with the spatial characteristics of the ultrasonic communication channel,and with the measuring accuracy.Let us dwell on the questions of general importance for ultrasonic ranging in air,namely:on the choice ofa carrier frequency and the amount of acoustic power received.An analysis shows that with conical directivity diagrams for the radiator and receiver,and assuming thatthe distance between radiator and receiver is substantially smaller than the distance to the obstacle,theamount of acoustic power arriving at the receiving area Pr for the case of reflection from an ideal planesurface located at right angles to the acoustic axis of the transducer comes towhere Prad is the amount of acoustic power radiated,B is the absorption coefficient for a plane wave inthe medium,L is the distance between the electroacoustic transducer and the test me -mber,d is the diameterof the radiator(receiver),assuming they are equal,and c~is the angle of the directivity diagram for theelectroacoustic transducer in the radiator.Both in Eq.(1)and below,the absorption coefficient is dependent on the amplitude and not on theintensity as in some works[1],and therefore we think it necessary to stress this difference.In the various problems of sound ranging on the test members of machines and structures,therelationship between the signal attenuations due to the absorption of a planewave and due to thegeometrical properties of the sound beam are,as a rule,quite different.It must be pointed out that the choiceof the geometrical parameters for the beam in specific practical cases is dictated by the shape of thereflecting surface and its spatial distortion relative to some average position.Let us consider in more detail the relationship betweenthe geometric and the power parameters ofacoustic beams for the most common cases of ranging on plane and cylindrical structural members.It is well known that the directional characteristic W of a circular piston vibrating in an infinite baffle is afunction of the ratio of the piston's diameter to the wavelength d/λ as found from the following expression:(2)where Jl is a Bessel function of the first order and α is the angle between a normal to the piston and aline projected from the center of the piston to the point of observation(radiation).From Eq.(2)it is readily found that a t w o-t o-o n e reduction in the sensitivity of a radiator with respectto sound pressure will occur at the angle（3）For angles α≤20.Eq.(3)can be simplified to（4） where c is the velocity of sound in the medimaa and f is the frequency of the radiated vibrations.It follows from Eq.(4)that when radiating into air where c=330 m/s e c,the necessary diameter of the radiator for a spedfied angle of the directivity diagram at the 0.5 level of pressure taken with respect to the fdc 76.05.0≈αaxis can befound to be（5）where disincm,f is in kHz,and α is in degrees of angle.Curves are shown in Fig.1 plotted from Eq.(5)for six angles of a radiator's directivity diagram.The directivity diagrm needed for a radiator is dictated by the maximum distance to be measured and bythe spatial disposition of the test member relative to the other structural members.In order to avoid theincidence of signals reflected from adjacent members onto the acoustic receiver,it is necessary to provide asmall angle of divergence for the sound beam and,as far as possible,a small-diameter radiator.These tworequirements are mutually inconsistent since for a given radiation frequency a reduction of the beam'sdivergence angle requires an increased radiator diameter.In fact,the diameter of the"sonicated"spot is controlled by two variables,namely:the diameter of theradiator and the divergence angle of the sound beam.In the general case the minimum diameter ofthe"sonicated"spot Dmin on a plane surface normally disposed to the radiator's axis is given by（6）where L is the least distance to the test surface. The specified value of Dmin corresponds to a radiator with a diameter（7）As seen from Eqs.(,6)and(7),the minimum diameter of the"sonieated"spot at the maximum requireddistancecannot be less than two radiator diameters.Naturally,with shorter distances to the obstacle the sizeof the"sonicated" surface is less.Let us consider the case of sound ranging on a cylindrically shaped object of radius R.The problem is to measure the distance from the electroacoustic transducer to the side surface of the cylinderwith its various possible displacements along the X and Y axes.The necessary angleαof the radiator'sdirectivity diagram is given in this case by the expression（8） whereα is the value of the angle for the directivity diagram,Ymax is the maximum displacement of the cylinder's center from the acoustic axis,and Lmin is the minimum distance from the center of theelectroacoustic transducer to the reflecting surface measured along the straight line connecting the center ofthe m e m b e r with the center of the transducer.It is clear that when measuring distance,the"running"time of the information signal is controlled by thefd α1400≈fcL d 5.1=fcLD 6min =min maxarcsinL R y +≥αlength of the path in a direction normal to the cylinder's surface,or in other words,the measure distance isalways the shortest one.This statement is correct for all cases of specular reflection of the vibrations from thetest surface.The simultaneous solution of Eqs.(2)and(8)when W=0.5 leads to the following expression:(9) In the particular case where the sound ranging takes place in air having c=330 m/sec,and on theasstunption that L min <<R,the necessary d i a m e t e r of a unidirectional piston radiator d can be found fromthe fomula (10) where d is in cm and f is in kHz. Curves are shown in Fig.2 for determining the necessary diameter of the radiator as a function of theratio of the cylinder's radius to the maximum displacement from the axis for four radiation frequencies.Alsoshown in this figure is the directivity diagram angle as a function of R and Y rnax for four ratios of m i n i m u mdistance to radius.The ultrasonic absorption in air is the second factor in determining the resolution of ultrasonic rangingdevices and their range of action.The results of physical investigations concerning the measurement ofultrasonic vibrations air are given in[1-3].Up until now there has been no unambiguous explanation of thediscrepancy between the theoretical and expe -rimental absorption results for ultrasonic vibrations inair.Thus,for frequencies in the order of 50 to 60 kHz at a temperature of+25oC and a relative humidity of37%the energy absorption coefficient for a plane wave is about 2.5dB/m while the theoretical value is 0.3 dB/m.The absorption coefficient B as a function of frequency for a temperature of+25o Cand a humidity of37%according to the data in[2]can be described by Table 1.The absorption coefficient depends on the relative humidity.Thus,for frequencies in the order of 10 to20kHz the highest value of the absorption coefficient occurs at 20%humidity[3],and at 40%humidity theabsorption is reduced by about two to one.For frequencies in the order of 60 kHz the maximum absorptionoccurs at 30.7o humidity,dropping when it is increased to 98% or lowered to 10%by a factor of approximatelyfour to one.The air temperature also has an appreciable effect on the ultrasonic absorption[1].When thetemperature of the medium is increased from+10 to+30,the absorption for frequencies between 30 and 50kHz increases by about three to one.Taking all the factors noted above into account we arrive at the following approximate values for theabsorption coefficient:at a frequency of 60 kHz /3min =0.15 m -1 and~max=0.5-1;at a frequency of 200 ()maxmin 76.0y L R d +=λmax25fy R d ≈kHz/~min=0.6 m -1 and B max =2 m -1.（11）The values for the minimum~min and rnaxil-num~max"transmittance"coefficients were obtained in thea bsence of aerosols and rain.Their difference is the result of the possible variations in temperature over therange from -3 0 to+50~and in relative hmnidity over the range from 10 to 98%.The overall value ofthe"transmittance"is obtained by multiplying the values of g and 0 for given values of L,f,and d.L I T E R A T U R E C I T E DMoscow(1957).Moscow(1960).附录B 中文翻译在空气中超声测距G. E. Rudashevski and A. A. Gorbatov在仪器技术中远程是最重要的一个问题。
超声波测距外文文献
International Journal of Computer science & Information Technology (IJCSIT), Vol 1, No 2, November 2009EFFECT OF VARIATION OF SEPARATION BETWEEN THE ULTRASONIC TRANSMITTER AND RECEIVER ON THE ACCURACY OF DISTANCE MEASUREMENTAjay Kumar Shrivastava1, Ashish Verma2 and S. P. Singh31Department of Computer Application, Krishna Institute of Engineering and Technology, Ghaziabad (U.P.), Indiaajay@2Department of Physics and Electronics, Dr H S Gour University, Sagar (M.P.), Indiavermaashish31@3Department of Electronics and Communication, Noida Institute of Engineering and Technology, Ghaziabad (U.P.), Indiasahdeopsingh@ABSTRACTAccuracy of distance measurement of an object from an observation point such as a stationary or moving vehicle, equipment or person is most important in large number of present day applications. Ultrasonic sensors are most commonly used due to its simplicity and low cost. The accuracy of the measured distance is dependent on the separation between the ultrasonic transmitter and receiver. This dependency has been studied and reported in this paper. The result shows that the accuracy of distance measured is dependent on the separation between the transmitter and the receiver.KEYWORDSAccuracy of distance measurement, Ultrasonic sensor, distance measurement, microcontroller, sewer pipeline inspection, sewer pipeline maintenance, robotics.1. INTRODUCTIONDistance measurement of an object in front or by the side of a moving or stationary entity is required in a large number of devices and gadgets. These devices may be small or large and also quite simple or complicated. Distance measurement systems for such applications are available. These use various kinds of sensors and systems. Low cost and accuracy as well as speed are important in most of the applications. Hence ultrasonic sensors are most commonly used. To maintain the accuracy of measured distance the separation between transmitter and receiver is very important. In this paper, we describe the results of a study on the variation of error of measurement of distance of an object by varying the separation between the transmitter and receiver of the ultrasonic sensors by using microcontroller P89C51RD2. Ultrasound sensors are very versatile in distance measurement. They are also providing the cheapest solutions. Ultrasound waves are suitable both for air and underwater use [1].19International Journal of Computer science & Information Technology (IJCSIT), Vol 1, No 2, November 2009Ultrasonic sensors are also quite fast for most of the common applications. In simpler system a low cost version of 8- bit microcontroller can be used to implement the system to lower the cost. We are applying this system for sewer inspection system. Sewer blockages have become quite common. The blockages have become more frequent due to the dumping of polythene bags, hair and solid materials into the sewer system [2], [3]. There has been no work done in this direction. This is a new study which is useful to find out the optimal separation between ultrasonic transmitter and receiver to measure small distances.2. PRINCIPLEUltrasonic transducer uses the physical characteristics and various other effects of ultrasound of a specific frequency. It may transmit or receive the ultrasonic signal of a particular strength. These are available in piezoelectric or electromagnetic versions. The piezoelectric type is generally preferred due to its lower cost and simplicity to use [5]. The transmitter and receiver are available either as single unit or as separate units. The Ultrasonic wave propagation velocity in the air is approximately 340 m/s, the same as sonic velocity. To be precise, the ultrasound velocity is governed by the medium, and the velocity in the air is calculated using the formula given below (1). V= 340+0.6(t-15) m/s t:temperature, °C (1)In this study, we assumed the temperature to be 20°C, so the velocity of ultrasound in the air is 343 m/s. Because the travel distance is very short, the travel time is little affected by temperature. It takes approximately 29.15µsec for the ultrasound to propagate through 1cm, so it is possible to have 1cm resolution in the system [6].3. EXPERIMENTAL SETUPThe system consists of a transmitter and a receiver module controlled by a microcontroller P89C51RD2. We have used a microcontroller development kit for testing of the system. We are using 40Khz ultrasound sensors for our experiments. The Simplified block diagram of the system is shown in Fig.1. In Fig. 1, the interrupt1 signal initiates the system. When the interrupt1 signal is generated, MCU starts the timer1 to measure time and simultaneously generates the controlled 40Khz pulses having a train of specific number of pulses. These pulses are applied to the amplifier circuit and after amplification the ultrasound transmitter transmits the pulse train in the direction of the object. These ultrasonic pulses are reflected from the object and travels back in different directions. These reflected waves arrive at receiver. After amplification and processing it generates signal interrupt. This is applied as interrupt2 to the MCU. Interrupt2 stops the timer1, and MCU calculates the time elapsed between the generation of the wave and reception of the wave. This time is proportional to the distance travelled by the waves. Using the formula, MCU calculates the distance of the obstacle and display it or transfer it to the part of the total system where it is used for further control. Using this elapsed time, we calculate the distance of the object from the ultrasonic sensors.20International Journal of Computer science & Information Technology (IJCSIT), Vol 1, No 2, November 2009INT1 MCU Ultrasound Transmitter CircuitTINT2 Receiver Amplifier Display RFig 1: Block Diagram of the System4. EXPERIMENTAL RESULTSThe waveforms of the transmitted and received waveforms of the ultrasonic signal is stored in Digital Storage Oscilloscope. We have taken the readings for various separation between tranmitter and reciever. We have measured the distance in the interval of 5cm. For every measured distance three reading have been taken. The table shows the average of the three readings. The maesured distance is calculated on the basis of travelled time. The formula to calculate the distance is given below: Dist. (cm) = (Travelled Time*10-6 * 34300) / 2 (2)The ultrasonic waves travelled from the transmitter to the object and from the object back to the receiver hence the whole distance is divided by two. Values of %Error have also been calculated and shown. The error result shows that there is some error in recording the start and finish times in the system. When the distance increases the error is distributed in a larger distance and hence the %error decreases. We have taken the measurements for various separations of transmitter and receiver renging from 2cm to 15cm. The Table 1 shows the results when separation between tranmitter and reciever is 2cm. Table 1: Experimental Results (For 2cm Separation between Transmitter and Reciever) S.No . 1 2 3 4 5 6 7 8 9 10 Actual Distance(cm) 5 10 15 20 25 30 35 40 45 50 Travelled Time (µSec) 400 690 1050 1250 1650 1930 2180 2400 2700 3000 Measured Distance (cm) 6.86 11.83 18.01 21.44 28.30 33.10 37.39 41.16 46.31 51.45 % Error 37.20 18.34 20.05 7.19 13.19 10.33 6.82 2.90 2.90 2.90The result shows that the acuracy of measured distance is increses for longer distances. The %error becomes constant for measured distances above 40cm. The highest %error is occured in small distance of 5cm. It is also shown by Fig.2.21International Journal of Computer science & Information Technology (IJCSIT), Vol 1, No 2, November 2009Fig. 2: Graph of Actual Distance versus Measured Distance for 2cm Separation between Transmitter and Reciever. The Table 2 shows the result when separation between transmitter a reciever is 5cm. Table 2: Experimental Results for 5cm Separation between Transmitter and reciever) S.No. 1 2 3 4 5 6 7 8 9 10 Actual Distance(cm) 5 10 15 20 25 30 35 40 45 50 Travelled Time (µSec) 410 700 1000 1300 1600 1870 2220 2500 2780 3120 Measured Distance (cm) 7.03 12.01 17.15 22.30 27.44 32.07 38.07 42.88 47.68 53.51 % Error 40.63 20.05 14.33 11.48 9.76 6.90 8.78 7.19 5.95 7.02The resluts shows that the accuracy is incresed in camparison to the previous results. This is also shown by the Fig. 3.Fig. 3: Graph of Actual Distance versus Measured Distance when Separation between Transmitter and Reciever is 5 cm.22International Journal of Computer science & Information Technology (IJCSIT), Vol 1, No 2, November 2009The Table 3 shows the results when separation between transmitter and reciever is 10 cm. These results indicates that when we increase the separation between transmitter and receiver the %error increses for small measured distances. Table 3: Experimental Results for Separation of 10cm between Transmitter and reciever)S.No. 1 2 3 4 5 6 7 8 9 10Actual Distance(cm) 5 10 15 20 25 30 35 40 45 50Travelled Time (µSec) 620 750 1010 1310 1600 1870 2200 2400 2680 3000Measured Distance (cm) 10.63 12.86 17.32 22.47 27.44 32.07 37.73 41.16 45.96 51.45% Error 112.66 28.63 15.48 12.33 9.76 6.90 7.80 2.90 2.14 2.90Again the accuracy increases with the distance but the small distances are not so accurate. The error is high for small distances. It is also shown by the Fig. 4.Fig. 4: Graph of Actual Distance versus Measured Distance when Separation between Transmitter and Reciever is 10 cm. The Table 4 is showing the result of measured distance when 15cm separation between transmitter and reciever. These results shows that when we increase the separation between transmitter and receiver the %error increses. This increase is very high in small measured distances like 5cm in our experiment. The lowest %error observed for the measured distance of 45cm and again it is increasing for the measured distance of 50cm. The results shows that we have to stop the increament of seaparation between transmitter and receiver in our experiment.23International Journal of Computer science & Information Technology (IJCSIT), Vol 1, No 2, November 2009Table 4: Experimental Results for 15cm Separation between Transmitter and Reciever) S.No. 1 2 3 4 5 6 7 8 9 10 Actual Distance(cm) 5 10 15 20 25 30 35 40 45 50 Travelled Time (µSec) 1300 930 1180 1350 1620 1900 2200 2420 2700 3200 Measured Distance (cm) 22.30 15.95 20.24 23.15 27.78 32.59 37.73 41.50 46.31 54.88 % Error 345.90 59.50 34.91 15.76 11.13 8.62 7.80 3.76 2.90 9.76Again the error for the small distance say 5cm is very high. It is also showing that the graph between actual distance versus measured distance is not a straight line. This graph is shown in Fig. 5.Fig. 5: Graph of Actual Distance versus Measured Distance for 15cm Separation between Transmitter and Reciever. The graph between the measured distance the actual distance indicates that the measured distance is proportional to the actual distance.5. ANALYSIS OF THE RESULTSThe experimental results shows that the distance measured for different separations between transmitter and receiver are accurate for long distances e.g. more than 20cm. For small actual distances say 5cm, the small transmitter and receiver distances are better in comparison to the long distances between transmitter and receiver. If we place the transmitter and receiver at 15cm separation than the small distance like 5cm are not going to be measured correctly. Result shows the error of 345%. Hence we have to place the transmitter and receiver at proper distance like 5-10cm. For long distances the distance between transmitter and receiver has very low impact on the accuracy. We have compared the all measured distances for different separations between transmitter and receiver and the results are shown in the Table 5.24International Journal of Computer science & Information Technology (IJCSIT), Vol 1, No 2, November 2009Table 5: Comparison of Measured Distances for different Separations between Transmitter and Reciever Actual Dist. (cm) 5 10 15 20 25 30 35 40 45 50 Measured Distance (in cm) when Separation between Transmitter and Reciever is = 2cm 6.86 11.83 18.01 21.44 28.30 33.10 37.39 41.16 46.31 51.45 5cm 7.03 12.01 17.15 22.30 27.44 32.07 38.07 42.88 47.68 53.51 10cm 10.63 12.86 17.32 22.47 27.44 32.07 37.73 41.16 45.96 51.45 15cm 22.30 15.95 20.24 23.15 27.78 32.59 37.73 41.50 46.31 54.88S. No. 1 2 3 4 5 6 7 8 9 10As we can see in the table that small measured distance like 5cm is measured accurately when 2cm separation between transmitter and receiver. It has the lowest error. When we increase the distance to be measured, the accuracy of measured distance are high and it the highest for 10cm separation between transmitter and receiver. Hence for the range of 5cm to 50cm, as we taken in our experiments, the separation between transmitter and receiver are 2cm to 10cm. If we increase this than the error percentage also increases. The Fig.6 shows the graph between actual distance and the different measured distances for various separations between transmitter and receiver.Fig. 6: Graph for Comparison of Measured Distances for different Separations between Transmitter and Reciever This graph is also showing that the graph plotting of measured distance when separation between transmitter and receiver is 2cm, 5cm and 10cm is almost on the same points. The graph plotting when 15cm separation between transmitter and receiver, is not very encouraging for this range of 5cm to 50cm.25International Journal of Computer science & Information Technology (IJCSIT), Vol 1, No 2, November 20096. CONCLUSIONSWe have done the experiments on our ultrasonic measurement system for the various separations between transmitter and receiver and the result shows that the measured distance is satisfactory for our study. When the distance increases the error becomes constant and very less. A correction may be applied to calculate the correct distance. Interrupt1 initiates the system and interrupt2 stops the timer and on the basis of the travelled time distance calculated. In future, the whole system will be mounted on the one PCB. This study shows that for small distances the separation between transmitter and receiver should be 5cm to 10cm. Hence this study will help in fixing the separation between transmitter and receiver in the robotic vehicle for blockage detection so we are able to calculate the more accurate distance of the blockage in the sewage filled sewer lines. Hence we can prevent human labour to go in the sewage filled sewer lines to detect the blockage which are very dangerous to the human as they contain the poisonous gases.ACKNOWLEDGMENTThis work is supported by MP Council of Science and Technology (MPCST), Bhopal, Project Code No. R&D/PHYSICS.23/08-09-1.REFERENCES[1] J. David and N cheeke “Fundamentals of Ultrasonic Waves” CRC Press, Florida, USA, 2002, ISBN 0-8493-0130-0. [2] Singh SP, Verma Ashish, Shrivastava AK “Design and Development of Robotic Sewer Inspection Equipment Controlled by Embedded Systems” Proceedings of the First IEEE International Conference on Emerging Trends in Engineering and Technology, July 16-18, 2008, Nagpur, India pp. 1317-1320. [3] Shrivastava AK, Verma Ashish, Singh SP “Partial Automation of the Current Sewer Cleaning System”, Invertis Journal of Science and Technology, Vol.1, No.4, 2008, pp 261-265. [4] O. Duran, K.Althoefer, and L Seneviratene, “State of the Art in Sensor Technologies for Sewer Inspection”, IEEE Sensors Journal, April 2002, Vol. 2, N.2, pp 63. [5] Hongjiang He, Jianyi Liu, “The Design of Ultrasonic Distance Measurement System Based on S3C2410” Proceedings of the 2008 IEEE International Conference on Intelligent Computation Technology and Automation, 20-22 Oct, 2008, pp. 44-47. [6] Yongwon Jang, Seungchul Shin, Jeong Won Lee, and Seunghwan Kim, “A Preliminary Study for Portable Walking Distance Measurement System Using Ultrasoinc Sensors” Proceedings of the 29th Annual International Conference of the IEEE EMBS Cité Internationale Lyon, France, Aug 23-26, 2007, pp. 5290-5293.26International Journal of Computer science & Information Technology (IJCSIT), Vol 1, No 2, November 2009AuthorsAjay Kumar Shrivastava was born at Guna (M.P.), India on 7th August, 1977. He had done his graduation in Electronics from Dr. H.S.Gour University, Sagar (M.P.), India in 1998. After that he had completed his MCA from the same university in 2002. He has more than seven years of teaching experience. He had worked as Lecturer in Technocrats Institute of Technology, Bhopal (M.P.), India for three years. Presently he is working as Associate Professor in Krishna Institute of Engineering and Technology, Ghaziabad (U.P.), India from Aug. 2005. His research interests include Embedded Systems and Data Mining. Mr. Shrivastava is the life member of Computer Society of India (CSI). He is also life member of Association of Computer, Electronics and Electrical Engineers (ACEEE) and International Association of Computer Science and Information Technology (IACSIT) and International Association of Engineers (IAENG). He is also the member of Computer Science Teachers Association (CSTA). He is also reviewer of various ACEEE organized conferences. He has published a paper in National Journal and published/presented four papers in conferences.Dr. Ashish Verma was born on 23rd March 1963. He received the M.Sc. degree in Physics with specialization in Electronics and solidstate physics in1984 and Ph.D. degree in Physics in 1991 from Dr. Hari Singh Gour Central University, Sagar, (M.P.), India. He has having 24 years of teaching (UG/PG) and research experience and is currently working as a Senior Lecturer in the department of Physics and Electronics, Dr. Hari Singh Gour Central University, Sagar. He has guided about 150 students (UG/PG) for their projects in the field of Electronics and Physics. He guided 4 Ph.D. students (One as Co-Supervisor). Presently, he is guiding 8 Ph.D. students for their innovative research. He is supervising 3 Ph.D. students in Physics and Electronics of M.P. BHOJ (Open) University, Bhopal, (M.P.), India. He had published a book entitled “Microprocessor”, Vishwavidyalaya Prakashan, Sagar (M.P.), India and written two chapters in “Bhotiki”, Madhya Pradesh Hindi Granth Academy, Bhopal (M.P.), India. Dr. Verma published / presented about 50 research papers in the National /International Journals / Conferences of high repute. He is the Executive Council (Government Nominee) in Government Girls Autonomous College, Sagar, (M.P.). He had worked in various committees of the university. Prof. S.P.Singh was born at village Manirampur in Nalanda district, Bihar, India on 10th June 1939. He did his schooling and intermediate studies at Patna. He completed his B.Sc.(Engg.) degree in Electrical Engineering from National Institute of Technology, Jamshedpur, India in the year 1964. He did M.Tech. in Electrical Engineering (Electronic Devices and Circuits) from Indian Institute of Technology, Kanpur, India in 1975. He obtained his Ph.D. degree from Ranchi University, Ranchi, India in the year 1993. His topic was microprocessor based speed control of induction motors.27International Journal of Computer science & Information Technology (IJCSIT), Vol 1, No 2, November 2009He joined N.I.T., Jamshedpur, India as Lecturer in Electrical Engineering in 1964 continued there as lecturer, AP and Professor till 1999. He started teaching electronic subjects and shifted to electronics engineering. After retirement from NIT in 1999, he continued to work as professor in institutes around Delhi. Currently, he is working as professor in Electronics & Communication Engineering at Noida Institute of Engineering and Technology, Greater Noida, U.P., India. Prof. Singh was a member of IEEE from 1974 to 1991. At present Dr. Singh is a fellow of I.E.T.E., India.28。
超声波测距系统外文文献翻译
=======大学本科生毕业设计外文文献及中文翻译文献题目： ULTRASONIC RANGING SYSTEM 文献出处： United States Patent译文题目：超声波测距系统学生：指导教师：专业班级：自动化11-4学号： 110601140416电气信息工程学院2014年5月1日超声波测距系统摘要超声波测距系统，是指选择性地激励一个变压器，使之产生换能器驱动信号。
超声换能器发射的超声波脉冲用于响应驱动信号然后接收到一个在超声波信号发出之后的回波信号。
分路开关接在变压器的绕组上，当超声波信号的传输在允许的近距离范围内达到一个稳定的等级，分路开关选择性的闭合来阻止蜂鸣器报警。
第1章发明背景像在宝丽来相机中应用的可用范围测试系统，它们都是准确而且可靠的，但都不适用于近距离测距，举个例子，2到3英寸的距离内就不适用，所以他们在9英寸甚至更远的距离测距是可靠的。
它们可以应用在很多的应用程序中，但不适用于可移动机器人领域内。
机器人通常必须通过门口只有两三英寸的间隙，如果当可移动机器人被操作于避障模式下通过狭小空间，可能机器人的规避路径过于狭窄，此外,规避动作应该使偏指定的路径距离最小化。
近距离测距不用于超声波系统的一个原因是，近距离输出脉冲输出太长以至于它重叠在回波脉冲上，即使输出脉冲缩短,输出脉冲仍然重叠回波脉冲，因为声音紧跟着输出脉冲。
备中产生的回波信号脉冲的范围为100毫伏，但设置传感器响应所必需的电路回声脉冲是大约150伏到300伏之间。
因此即使是最小的声波也会盖过回声信号。
事实上,dual-diode钳位电路用于将150伏降低到二极管的击穿电压，即0.7伏特。
但是这700毫伏足以盖过100毫伏的回波信号。
目前系统需要50毫秒将300伏特的峰值发射电压降到0.7伏特，且额外需要500到600毫秒的时间将它稳定在1毫伏范围。
第2章发明总结本发明可以提供一种改进的超声波测距系统。
本发明也可以提供一个改进的多通道超声波测距系统。
超声测距外文-超声波距离和速度利用互相关方法对LPM信号测量
Ultrasonic distance and velocity measurement using a pair of LPM signals for cross-correlation method:Improvement of Doppler-shift compensation and examination of Doppler velocity estimation超声波距离和速度利用互相关方法对LPM信号测量：多普勒频移补偿和多普勒速度估计检测的改进数据来源Elsevier Journal Elsevier期刊刊物名Ultrasonics, 2012, Vol.52 (7), pp.873-879 超声波，2012，卷（7），pp.873-879 作者Shinnosuke Hirata, Minoru Kuribayashi Kurosawashinnosuke平田，稔栗林黑泽明单位机械工程与智能系统1，信息工程学院，电子通信，1-5-1 chofugaoka e4-329，，，布，东京182-8585大学，日本信息处理系，跨学科研究生科学与工程学院，东京工业大学，4259首席人事官g2-32，长津田，绿区，横滨，神奈川226-8502，日本AbstractReal-time distance measurement of a moving object with high accuracy and high resolution using an ultrasonic wave is difficult due to the influence of the Doppler effect or the limit of the calculation cost of signal processing. An over-sampling signal processing method using a pair of LPM signals has been proposed for ultrasonic distance and velocity measurement of moving objects with high accuracy and high resolution. The proposed method consists of cross correlation by single-bit signal processing, high-resolution Doppler velocity estimation with wide measurement range and low-calculation-cost Doppler-shift compensation. The over-sampling cross-correlation function is obtained from cross correlation by single-bit signal processing with low calculation cost. The Doppler velocity and distance of the object are determined from the peak interval and peak form in the cross-correlation function by the proposed method of Doppler velocity estimation and Doppler-shift compensation. In this paper, the proposed method of Doppler-shift compensation is improved. Accuracy of the determined distance was improved from approximately within ±140 μm in the previous method to approximately within ±10μm in computer simulations. Then, the proposed method of Doppler velocity estimation is evaluated. In computer simulations, accuracy of the determined Doppler velocity and摘要实时测量移动物体的高精度和高分辨率超声波存在的多普勒效应或信号处理的计算成本的限制的影响。
单片机-外文翻译-外文文献-英文文献-基于单片机的超声波测距系统的研究与设计
附录附录A外文翻译the equivalent dc value. In the analysis of electronic circuits to be considered in a later course, both dc and ac sources of voltage will be applied to the same network. It will then be necessary to know or determine the dc (or average value) and ac components of the voltage or current in various parts of the system.EXAMPLE 13.13 Determine the average value of the waveforms of Fig. 13.37.FIG. 13.37Example 13.13.Solutions:a. By inspection, the area above the axis equals the area below over one cycle, resulting in an average value of zero volts.b. Using Eq.(13.26):as shown in Fig. 13.38.In reality, the waveform of Fig. 13.37(b) is simply the square wave of Fig. 13.37(a) with a dc shift of 4 V; that is v2 =v1 + 4 VEXAMPLE 13.14 Find the average values of the following waveforms over one full cycle:a.Fig. 13.39.b. Fig. 13.40.Solutions:We found the areas under the curves in the preceding example by using a simple geometric formula. If we should encounter a sine wave or any other unusual shape, however, we must find the area by some other means. We can obtain a good approximation of the area by attempting to reproduce the original wave shape using a number of small rectangles or other familiar shapes, the area of which we already know through simple geometric formulas. For example,the area of the positive (or negative) pulse of a sine wave is 2Am.Approximating this waveform by two triangles (Fig. 13.43), we obtain(using area1/2 base height for the area of a triangle) a rough idea of the actual area:A closer approximation might be a rectangle with two similar triangles(Fig. 13.44):which is certainly close to the actual area. If an infinite number of forms were used, an exact answer of 2Am could be obtained. For irregular waveforms, this method can be especially useful if data such as the average value are desired. The procedure of calculus that gives the exact solution 2Am is known as integration. Integration is presented here only to make the method recognizable to the reader; it is not necessary to be proficient in its use to continue with this text. It is a useful mathematical tool, however,and should be learned. Finding the area under the positive pulse of a sine wave using integration, we havewhere ∫ is the sign of integration, 0 and p are the limits of integration, Am sin a is the function to be integrated, and d a indicates that we are integrating with respect to a. Integrating, we obtainSince we know the area under the positive (or negative) pulse, we can easily determine the average value of the positive (or negative) region of a sine wave pulse by applying Eq. (13.26):For the waveform of Fig. 13.45,EXAMPLE 13.15 Determine the average value of the sinusoidal waveform of Fig.13.46.Solution: By inspection it is fairly obvious thatthe average value of a pure sinusoidal waveform over one full cycle iszero.EXAMPLE 13.16 Determine the average value of the waveform of Fig. 13.47.Solution: The peak-to-peak value of the sinusoidal function is16 mV +2 mV =18 mV. The peak amplitude of the sinusoidal waveform is, therefore, 18 mV/2 =9 mV. Counting down 9 mV from 2 mV(or 9 mV up from -16 mV) results in an average or dc level of -7 mV,as noted by the dashed line of Fig. 13.47.EXAMPLE 13.17 Determine the average value of the waveform of Fig. 13.48.Solution:EXAMPLE 13.18 For the waveform of Fig. 13.49, determine whether the average value is positive or negative, and determine its approximate value.Solution: From the appearance of the waveform, the average value is positive and in the vicinity of 2 mV. Occasionally, judgments of this type will have to be made. InstrumentationThe dc level or average value of any waveform can be found using a digital multimeter (DMM) or an oscilloscope. For purely dc circuits,simply set the DMM on dc, and read the voltage or current levels.Oscilloscopes are limited to voltage levels using the sequence of steps listed below:1. First choose GND from the DC-GND-AC option list associated with each vertical channel. The GND option blocks any signal to which the oscilloscope probe may be connected from entering the oscilloscope and responds with just a horizontal line. Set the resulting line in the middle of the vertical axis on the horizontal axis, as shown in Fig. 13.50(a).2. Apply the oscilloscope probe to the voltage to be measured (if not already connected), and switch to the DC option. If a dc voltage is present, the horizontal line will shift up or down, as demonstrated in Fig. 13.50(b). Multiplying the shift by the vertical sensitivity will result in the dc voltage. An upward shift is a positive voltage (higherpotential at the red or positive lead of the oscilloscope), while a downward shift is a negative voltage (lower potential at the red or positive lead of the oscilloscope). In general,1. Using the GND option, reset the horizontal line to the middle of the screen.2. Switch to AC (all dc components of the signal to which the probe is connected will be blocked from entering the oscilloscope—only the alternating, or changing, components will be displayed).Note the location of some definitive point on the waveform, such as the bottom of the half-wave rectified waveform of Fig. 13.51(a); that is, note its position on the vertical scale. For the future, whenever you use the AC option, keep in mind that the computer will distribute the waveform above and below the horizontal axis such that the average value is zero; that is, the area above the axis will equal the area below.3. Then switch to DC (to permit both the dc and the ac components of the waveform to enter the oscilloscope), and note the shift in the chosen level of part 2, as shown in Fig.13.51(b). Equation(13.29) can then be used to determine the dc or average value of the waveform. For the waveform of Fig. 13.51(b), the average value is aboutThe procedure outlined above can be applied to any alternating waveform such as the one in Fig. 13.49. In some cases the average value may require moving the starting position of the waveform under the AC option to a different region of the screen or choosing a higher voltage scale. DMMs can read the average or dc level of any waveform by simply choosing the appropriate scale.13.7 EFFECTIVE (rms) V ALUESThis section will begin to relate dc and ac quantities with respect to the power delivered to a load. It will help us determine the amplitude of a sinusoidal ac current required to deliver the same power as a particular dc current. The question frequently arises, How is it possible for a sinusoidal ac quantity to deliver a net power if, over a full cycle, the net current in any one direction is zero (average value 0)? It would almost appear that the power delivered during the positive portion of the sinusoidal waveform is withdrawn during the negative portion, and since the two are equal in magnitude, the net power delivered is zero. However, understand that irrespective of direction, current of any magnitude through a resistor will deliver power to that resistor. In other words, during the positive or negative portions of a sinusoidal ac current, power is being delivered at eachinstant of time to the resistor. The power delivered at each instant will, of course, vary with the magnitude of the sinusoidal ac current, but there will be a net flow during either the positive or the negative pulses with a net flow over the full cycle. The net power flow will equal twice that delivered by either the positive or the negative regions of sinusoidal quantity. A fixed relationship between ac and dc voltages and currents can be derived from the experimental setup shown in Fig. 13.52. A resistor in a water bath is connected by switches to a dc and an ac supply. If switch 1 is closed, a dc current I, determined by the resistance R and battery voltage E, will be established through the resistor R. The temperature reached by the water is determined by the dc power dissipated in the form of heat by the resistor.If switch 2 is closed and switch 1 left open, the ac current through the resistor will have a peak value of Im. The temperature reached by the water is now determined by the ac power dissipated in the form of heat by the resistor. The ac input is varied until the temperature is the same as that reached with the dc input. When this is accomplished, the average electrical power delivered to the resistor R by the ac source is the same as that delivered by the dc source. The power delivered by the ac supply at any instant of time isThe average power delivered by the ac source is just the first term, since the average value of a cosine wave is zero even though the wave may have twice the frequency of the original input current waveform. Equating the average power delivered by the ac generator to that delivered by the dc source,which, in words, states thatthe equivalent dc value of a sinusoidal current or voltage is 1/2or 0.707 of its maximum value.The equivalent dc value is called the effective value of the sinusoidal quantity.In summary,As a simple numerical example, it would require an ac current with a peak value of 2 (10) 14.14 A to deliver the same power to the resistor in Fig. 13.52 as a dc current of 10 A. The effective value of any quantity plotted as a function of time can be found by using the following equation derived from the experiment just described:which, in words, states that to find the effective value, the function i(t) must first be squared. After i(t) is squared, the area under the curve isfound by integration. It is then divided by T, the length of the cycle or the period of the waveform, to obtain the average or mean value of thesquared waveform. The final step is to take the square root of the meanvalue. This procedure gives us another designation for the effectivevalue, the root-mean-square (rms) value. In fact, since the rms term isthe most commonly used in the educational and industrial communities,it will used throughout this text. EXAMPLE 13.19 Find the rms values of the sinusoidal waveform in each part of Fig.13.53.Solution: For part (a), I rms 0.707(12 10 3 A) 8.484 mA.For part (b), again I rms 8.484 mA. Note that frequency did notchange the effective value in (b) above compared to (a). For part (c),V rms 0.707(169.73 V) 120 V, the same as available from a home outlet. EXAMPLE 13.20 The 120-V dc source of Fig. 13.54(a) delivers 3.6 W to the load. Determine the peak value of the applied voltage (Em) and the current (Im) if the ac source [Fig. 13.54(b)] is to deliver the same power to the load.Solution:EXAMPLE 13.21 Find the effective or rms value of the waveform of Fig. 13.55.Solution:EXAMPLE 13.22 Calculate the rms value of the voltage of Fig. 13.57.Solution:EXAMPLE 13.23 Determine the average and rms values of the square wave of Fig.13.59.Solution: By inspection, the average value is zero.The waveforms appearing in these examples are the same as thoseused in the examples on the average value. It might prove interesting tocompare the rms and average values of these waveforms.The rms values of sinusoidal quantities such as voltage or currentwill be represented by E and I. These symbols are the same as thoseused for dc voltages and currents. To avoid confusion, the peak valueof a waveform will always have a subscript m associated with it: Im sin q t. Caution: When finding the rms value of the positive pulse of asine wave, note that the squared area is not simply (2Am)2 4A2m; itmust be found by a completely new integration. This will always bethe case for any waveform that is not rectangular.A unique situation arises if a waveform has both a dc and an ac componentthat may be due to a source such as the one in Fig. 13.61. Thecombination appears frequently in the analysis of electronic networkswhere both dc and ac levels are present in the same system.The question arises, What is the rms value of the voltage vT? Onemight be tempted to simply assume that it is the sum of the rms valuesof each component of the waveform; that is, VT rms 0.7071(1.5 V) 6 V 1.06 V 6 V 7.06 V. However, the rms value is actuallydetermined bywhich for the above example is直流值相等。
毕业论文外文文献翻译Ultrasonic-ranging-system-design超声测距系统设计
毕业设计（论文）外文文献翻译文献、资料中文题目：超声测距系统设计文献、资料英文题目：Ultrasonic ranging system design 文献、资料来源：文献、资料发表（出版）日期：院（部）：专业：班级：姓名：学号：指导教师：翻译日期： 2017.02.14Ultrasonic ranging system designPublication title: Sensor Review. Bradford: 1993.Vol.ABSTRACT: Ultrasonic ranging technology has wide using worth in many fields, such as the industrial locale, vehicle navigation and sonar engineering. Now it has been used in level measurement, self-guided autonomous vehicles, fieldwork robots automotive navigation, air and underwater target detection, identification, location and so on. So there is an important practicing meaning to learn the ranging theory and ways deeply. To improve the precision of the ultrasonic ranging system in hand, satisfy the request of the engineering personnel for the ranging precision, the bound and the usage, a portable ultrasonic ranging system based on the single chip processor was developed.Keywords: Ultrasound, Ranging System, Single Chip Processor1. IntroductiveWith the development of science and techno logy, the improvement of people’s standard of living, speeding up the development and construction of the city. Urban drainage system have greatly developed their situation is construction improving. However, due to historical reasons many unpredictable factors in the synthesis of her time, the city drainage system. In particular drainage system often lags behind urban construction. Therefore, there are often good building excavation has been building facilities to upgrade the drainage system phenomenon. It brought to the city sewage, and it is clear to the city sewage and drainage culvert in the sewage treatment system. Comfort is very important to people’s lives. Mobile robots designed to clear the drainage culvert and the automatic control system Free sewage culvert clear guarantee robots, the robot is designed to clear the culvert sewage to the core. Control system is the core component of the development of ultrasonic range finder. Therefore, it is very important to design a good ultrasonic range finder.2. A principle of ultrasonic distance measurementThe application of AT89C51:SCM is a major piece of computer components are integrated into the chip micro-computer. It is a multi-interface and counting on the micro-controller integration, and intelligence products are widely used in industrial automation. and MCS-51 microcontroller is a typical and representative.Microcontrollers are used in a multitude of commercial applications such as modems, motor-control systems, air conditioner control systems, automotive engine and among others. The high processing speed and enhanced peripheral set of these microcontrollers make them suitable for such high-speed event-based applications. However, these critical application domains also require that these microcontrollers are highly reliable. The high reliability and low market risks can be ensured by a robust testing process and a proper tools environment for the validation of these microcontrollers both at the component and at the system level. Intel Plaform Engineering department developed an object-oriented multi-threaded test environment for the validation of its AT89C51 automotive microcontrollers. The goals of this environment was not only to provide a robust testing environment for the AT89C51 automotive microcontrollers, but to develop an environment which can be easily extended and reused for the validation of several other future microcontrollers. The environment was developed in conjunction with Microsoft Foundation Classes(AT89C51).1.1 Features* Compatible with MCS-51 Products* 2Kbytes of Reprogrammable Flash MemoryEndurance: 1,000Write/Erase Cycles* 2.7V to 6V Operating Range* Fully Static operation: 0Hz to 24MHz* Two-level program memory lock* 128x8-bit internal RAM* 15programmable I/O lines* Two 16-bit timer/counters* Six interrupt sources*Programmable serial UART channel* Direct LED drive output* On-chip analog comparator* Low power idle and power down modes1.2 DescriptionThe AT89C2051 is a low-voltage, high-performance CMOS 8-bit microcomputer with 2Kbytes of flash programmable and erasable read only memory (PEROM). The device is manufactured using Atmel’s high density nonvolatile memory technology and is compatible with the industry standard MCS-51 instruction set and pinout. By combining a versatile 8-bit CPU with flash on a monolithic chip, the Atmel AT89C2051 is a powerful microcomputer which provides a highly flexible and cost effective solution to many embedded control applications.The AT89C2051 provides the following standard features: 2Kbytes of flash,128bytes of RAM, 15 I/O lines, two 16-bit timer/counters, a five vector two-level interrupt architecture, a full duplex serial port, a precision analog comparator, on-chip oscillator and clock circuitry. In addition, the AT89C2051 is designed with static logicfor 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 freezer the oscillator disabling all other chip functions until the next hardware reset.1.3 Pin Configuration1.4 Pin DescriptionVCC Supply voltage.GND Ground.Prot 1Prot 1 is an 8-bit bidirectional I/O port. Port pins P1.2 to P1.7 provide internal pullups. P1.0 and P1.1 require external pullups. P1.0 and P1.1 also serve as the positive input (AIN0) and the negative input (AIN1), respectively, of the on-chip precision analog comparator. The port 1 output buffers can sink 20mA and can drive LED displays directly. When 1s are written to port 1 pins, they can be used as inputs. When pins P1.2 to P1.7 are used as input and are externally pulled low, they will source current (IIL) because of the internal pullups.Port 3Port 3 pins P3.0 to P3.5, P3.7 are seven bidirectional I/O pins with internal pullups. P3.6 is hard-wired as an input to the output of the on-chip comparator and is not accessible as a general purpose I/O pin. The port 3 output buffers can sink 20mA. 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 the AT89C2051 as listed below.1.5 Programming the FlashThe AT89C2051 is shipped with the 2 Kbytes of on-chip PEROM code memory array in the erased state (i.e., contents=FFH) and ready to be programmed. The code memory array is programmed one byte at a time. Once the array is programmed, to re-program any non-blank byte, the entire memory array needs to be erased electrically.Internal address counter: the AT89C2051 contains an internal PEROM address counter which is always reset to 000H on the rising edge of RST and is advanced applying a positive going pulse to pin XTAL1.Programming algorithm: to program the AT89C2051, the following sequence is recommended.1. power-up sequence:Apply power between VCC and GND pins Set RST and XTAL1 to GNDWith all other pins floating , wait for greater than 10 milliseconds2. Set pin RST to ‘H’ set pin P3.2 to ‘H’3. Apply the appropriate combination of ‘H’ or ‘L’ logic to pins P3.3, P3.4, P3.5,P3.7 to select one of the programming operations shown in the PEROM programming modes table.To program and Verify the Array:4. Apply data for code byte at location 000H to P1.0 to P1.7.5.Raise RST to 12V to enable programming.5. Pulse P3.2 once to program a byte in the PEROM array or the lock bits. The byte-write cycle is self-timed and typically takes 1.2ms.6. To verify the programmed data, lower RST from 12V to logic ‘H’ level and set pins P3.3 to P3.7 to the appropriate levels. Output data can be read at the port P1 pins.7. To program a byte at the next address location, pulse XTAL1 pin once to advance the internal address counter. Apply new data to the port P1 pins.8. Repeat steps 5 through 8, changing data and advancing the address counter for the entire 2 Kbytes array or until the end of the object file is reached.9. Power-off sequence: set XTAL1 to ‘L’ set RST to ‘L’Float all other I/O pins Turn VCC power off2.1 The principle of piezoelectric ultrasonic generatorPiezoelectric ultrasonic generator is the use of piezoelectric crystal resonators to work. Ultrasonic generator, the internal structure as shown, it has two piezoelectric chip and a resonance plate. When it’s two plus pulse signal, the frequency equal to the intrinsic piezoelectric oscillation frequency chip, the chip will happen piezoelectric resonance, and promote the development of plate vibration resonance, ultrasound is generated. Conversely, it will be for vibration suppression of piezoelectric chip, the mechanical energy is converted to electrical signals, then it becomes the ultrasonic receiver.The traditio nal way to determine the moment of the echo’s arrival is based on thresholding the received signal with a fixed reference. The threshold is chosen well above the noise level, whereas the moment of arrival of an echo is defined as the first moment the echo signal surpasses that threshold. The intensity of an echo reflecting from an object strongly depends on the object’s nature, size and distance from the sensor. Further, the time interval from the echo’s starting point to the moment when it surpasses the threshold changes with the intensity of the echo. As a consequence, a considerable error may occur even two echoes with different intensities arriving exactly at the same time will surpass the threshold at different moments. The stronger one will surpass the threshold earlier than the weaker, so it will be considered as belonging to a nearer object.2.2 The principle of ultrasonic distance measurementUltrasonic transmitter in a direction to launch ultrasound, in the moment to launch the beginning of time at the same time, the spread of ultrasound in the air, obstacles on his way to return immediately, the ultrasonic reflected wave received by the receiverimmediately stop the clock. Ultrasound in the air as the propagation velocity of 340m/s, according to the timer records the time t, we can calculate the distance between the launch distance barrier(s), that is: s=340t / 23. Ultrasonic Ranging System for the Second Circuit DesignSystem is characterized by single-chip microcomputer to control the use of ultrasonic transmitter and ultrasonic receiver since the launch from time to time, single-chip selection of 875, economic-to-use, and the chip has 4K of ROM, to facilitate programming.3.1 40 kHz ultrasonic pulse generated with the launchRanging system using the ultrasonic sensor of piezoelectric ceramic sensorsUCM40, its operating voltage of the pulse signal is 40kHz, which by the single-chip implementation of the following procedures to generate.puzel: mov 14h, # 12h; ultrasonic firing continued 200msHere: cpl p1.0; output 40kHz square wavenop;nop;nop;djnz 14h, here;retRanging in front of single-chip termination circuit P1.0 input port, single chip implementation of the above procedure, the P1.0 port in a 40kHz pulse output signal, after amplification transistor T, the drive to launch the first ultrasonic UCM40T, issued 40kHz ultrasonic pulse, and the continued launch of 200ms. Ranging the right and the left side of the circuit, respectively, then input port P1.1 and P1.2, the working principle and circuit in front of the same location.3.2 Reception and processing of ultrasonicUsed to receive the first launch of the first pair UCM40R, the ultrasonic pulse modulation signal into an alternating voltage, the op-amp amplification IC1A and after polarization IC1B to IC2. IC2 is locked loop with audio decoder chip LM567, internal voltage-controlled oscillator center frequency of f0=1/1.1R8C3, capacitor C4 determinetheir target bandwidth. R8-conditioning in the launch of the high jump 8 feet into a low-level, as interrupt request signals to the single-chip processing.Ranging in front of single-chip termination circuit output port INT0 interrupt the highest priority, right or left location of the output circuit with output gate IC3A access INT1 port single-chip, while single-chip P1.3 and P1.4 received input IC3A, interrupted by the process to identify the source of inquiry to deal with, interrupt priority level for the first left right after. Part of the source code is as follows:Receivel: push pswpush accclr ex1; related external interrupt 1jnb p1.1, right; P1.1 pin to 0, ranging from right to interrupt service routine circuitjnb p1.2, left; P1.2 pin to 0, to the left ranging circuit interrupt service routinereturn: SETB EX1; open external interrupt 1pop accpop pswretiright: …; right location entrance circuit interrupt service routineAjmp Returnleft: …; left ranging entrance circuit interrupt service routineAjmp Return3.3 The calculation of ultrasonic propagation timeWhen you start firing at the same time start the single-chip circuitry within the timer T0, the use of timer counting function records the time and the launch of ultrasonic reflected wave received time. When you receive the ultrasonic reflected wave, the receiver circuit output a negative jump in the end of INT0 or INT1 interrupt request generates a signal, single-chip microcomputer in response to external interrupt request, the implementation of the external interrupt service subroutine, read the time difference, calculating the distance. Some of its source code is as follows:RECEIVE0: PUSH PSWPUSH ACCCLR EX0; related external interrupt 0MOV R7, TH0; read the time valueMOV R6, TL0CLR CMOV A, R6SUBB A, #0BBH; calculate the time differenceMOV 31H, A; storage resultsMOV A, R7SUBB A, # 3CHMOV 30H, ASETB EX0; open external interrupt 0\POP ACCPOP PSWRETIFor a flat target, a distance measurement consists of two phases: a coarse measurement and a fine measurement:Step 1: Transmission of one pulse train to produce a simple ultrasonic wave.Step 2: Changing the gain of both echo amplifiers according to equation, until the echo is detected.Step 3: Detection of the amplitudes and zero-crossing times of both echoes.Step 4: Setting the gains of both echo amplifiers to normalize the output at, say 3 volts. Setting the period of the next pulses according to the: period of echoes. Setting the time window according to the data of step 2.Step 5: Sending two pulse trains to produce an interfered wave. Testing the zero-crossing times and amplitudes of the echoes. If phase inversion occurs in the echo, determine to otherwise calculate to by interpolation using the amplitudes near the trough. Derive t sub m1 and t sub m2.Step 6: Calculation of the distance y using equation.4、The ultrasonic ranging system software designSoftware is divided into two parts, the main program and interrupt service routine. Completion of the work of the main program is initialized, each sequence of ultrasonic transmitting and receiving control.Interrupt service routines from time to time to complete three of the rotation direction of ultrasonic launch, the main external interrupt service subroutine to read the value of completion time, distance calculation, the results of the output and so on.5、ConclusionsRequired measuring range of 30cm-200cm objects inside the plane to do a number of measurements found that the maximum error is 0.5cm, and good reproducibility. Single-chip design can be seen on the ultrasonic ranging system has a hardware structure is simple, reliable, small features such as measurement error. Therefore, it can be used not only for mobile robot can be used in other detection system.Thoughts: As for why the receiver do not have the transistor amplifier circuit, because the magnification well, integrated amplifier, but also with automatic gain control level, magnification to 76dB, the center frequency is 38k to 40k, is exactly resonant ultrasonic sensors frequency.6、Parking sensor6.1 Parking sensor introductionReversing radar, full name is "reversing the anti-collision radar, also known as" parking assist device, car parking or reversing the safety of assistive devices, ultrasonic sensors(commonly known as probes), controls and displays (or buzzer)and other components. To inform the driver around the obstacle to the sound or a moreintuitive display to lift the driver parking, reversing and start the vehicle around tovisit the distress caused by, and to help the driver to remove the vision deadends and blurred vision defects and improve driving safety.6.2 Reversing radar detection principleReversing radar, according to high-speed flight of the bats in thenight, not collided with any obstacle principles of design anddevelopment. Probe mounted on the rear bumper, according to different price and brand, the probe only ranging from two, three, four, six, eight,respectively, pipe around. The probe radiation, 45-degree angle up and downabout the search target. The greatest advantage is to explore lower than the bumper of the driver from the rear window is difficult to see obstacles, and the police, suchas flower beds, children playing in the squatting on the car.Display parking sensor installed in the rear view mirror, it constantlyremind drivers to car distance behindthe object distance to the dangerous distance, the buzzer starts singing, allow the driver to stop. When the gear lever linked into reverse gear, reversing radar, auto-start the work, the working range of 0.3 to 2.0 meters, so stop when the driver was very practical. Reversing radar is equivalent to an ultrasound probe for ultrasonic probe can be divided into two categories: First, Electrical, ultrasonic, the second is to use mechanical means to produce ultrasound, in view of the more commonly used piezoelectric ultrasonic generator, it has two power chips and a soundingboard, plus apulse signal when the poles, its frequency equal to the intrinsic oscillation frequency of the piezoelectric pressure chip will be resonant and drivenby the vibration of the sounding board, the mechanical energy into electrical signal, which became the ultrasonic probe works. In order to better study Ultrasonic and use up, people have to design and manufacture of ultrasonic sound, the ultrasonic probe tobe used in the use of car parking sensor. With this principle in a non-contactdetection technology for distance measurement is simple, convenient and rapid, easyto do real-time control, distance accuracy of practical industrial requirements. Parking sensor for ranging send out ultrasonic signal at a givenmoment, and shot in the face of the measured object back to the signal wave, reversing radar receiver to use statistics in the ultrasonic signal from the transmitter to receive echo signals calculate the propagation velocity in the medium, which can calculate the distance of the probe and to detect objects.6.3 Reversing radar functionality and performanceParking sensor can be divided into the LCD distance display, audible alarm, and azimuth directions, voice prompts, automatic probe detection function is complete, reversing radar distance, audible alarm, position-indicating function. A good performance reversing radar, its main properties include: (1) sensitivity, whether theresponse fast enough when there is an obstacle. (2) the existence of blind spots. (3) detection distance range.6.4 Each part of the roleReversing radar has the following effects: (1) ultrasonic sensor: used tolaunch and receive ultrasonic signals, ultrasonic sensors canmeasure distance. (2) host: after the launch of the sine wave pulse to the ultrasonic sensors, and process the received signal, to calculate the distance value, the data and monitor communication. (3) display or abuzzer: the receivinghost from the data, and display the distance value and provide differentlevels according to the distance from the alarm sound.6.5 Cautions1, the installation height: general ground: car before the installation of 45 ~55: 50 ~ 65cmcar after installation. 2, regular cleaningof the probe to prevent the fill. 3, do not use the hardstuff the probe surface cover will produce false positives or ranging allowed toprobe surface coverage, such as mud. 4, winter to avoid freezing. 5, 6 / 8 probe reversing radar before and after the probe is not free to swap may cause the ChangMing false positive problem. 6, note that the probe mounting orientation, in accordance with UP installation upward. 7, the probe is not recommended to install sheetmetal, sheet metal vibration will cause the probe resonance, resulting in false positives.超声测距系统设计原文出处：传感器文摘布拉福德：1993年超声测距技术在工业现场、车辆导航、水声工程等领域具有广泛的应用价值，目前已应用于物位测量、机器人自动导航以及空气中与水下的目标探测、识别、定位等场合。
超声波导盲仪及语音提示系统英文文献
毕业设计（论文）外文参考资料及译文译文题目：Ultrasonic distance meter超声波测距仪学生姓名：张宪旺学号： 1004104013 专业：自动化所在学院：机电工程学院指导教师：赵国树职称：讲师2014年01月08日超声测距系统设计原文出处：传感器文摘布拉福德:1993年第13页摘要：超声测距技术在工业现场、车辆导航、水声工程等领域都具有广泛的应用价值，目前已应用于物位测量、机器人自动导航以及空气中与水下的目标探测、识别、定位等场合。
因此，深入研究超声的测距理论和方法具有重要的实践意义。
为了进一步提高测距的精确度，满足工程人员对测量精度、测距量程和测距仪使用的要求，本文研制了一套基于单片机的便携式超声测距系统。
关键词：超声波，测距仪，单片机1、前言随着科技的发展，人们生活水平的提高，城市发展建设加快，城市给排水系统也有较大发展，其状况不断改善。
但是，由于历史原因合成时间住的许多不可预见因素，城市给排水系统，特别是排水系统往往落后于城市建设。
因此，经常出现开挖已经建设好的建筑设施来改造排水系统的现象。
城市污水给人们带来了困扰，因此箱涵的排污疏通对大城市给排水系统污水处理，人们生活舒适显得非常重要。
而设计研制箱涵排水疏通移动机器人的自动控制系统，保证机器人在箱涵中自由排污疏通，是箱涵排污疏通机器人的设计研制的核心部分。
控制系统核心部分就是超声波测距仪的研制。
因此，设计好的超声波测距仪就显得非常重要了。
2、超声波测距原理2.1压电式超声波发生器原理压电式超声波发生器实际上是利用压电晶体的谐振来工作的。
超声波发生器内部结构，它有两个压电晶片和一个共振板。
当它的两极外加脉冲信号，其频率等于压电晶片的固有振荡频率时，压电晶片将会发生共振，并带动共振板振动，便产生超声波。
反之，如果两电极间未外加电压，当共振板接收到超声波时，将压迫压电晶片作振动，将机械能转换为电信号，这时它就成为超声波接收器了。
高精度超声波测距系统英文原文
High-precision Ultrasonic Ranging SystemAbstractThe ultrasound is easy to transmit and has good reflection. Its speed is far less than the speed of flight. So this paper designs an ultrasonic ranging system based on STC89C52RC. This system can be effective in the range of about372 cm. After repeated test, the measurement error can be less than 1 cm. So this system can be applied to intelligent avoidanceand vehicle transportation and other systems.Key words: SCM; ultrasound; send; receive; ranging;temperature compensationI. INTRODUCTIONAt present, the main methods of ultrasonic ranging include pulse-echo method, phase modulation, frequency modulation and FFT-based approach. In these methods, the pulse-echo method has good adaptability; this method not only can be used for manual testing, but also combined with the automated systems. So it is most widely used at home and aboard.Nowadays, the theories of microwave and laser ranging have been applied to the ultrasonic ranging system. It can be a very good research. On the other hand, the filtering and analysis of the echo can also draw more and more attention of many experts and scholars. With the enhanced understanding of the ultrasonic theory, we know how to improve the precision and the anti-jamming capabilities will be the most the important performance indicators.In this paper, the pulse-echo theory is used to design the entire system. The following content is mainly divided into three parts. The first section describes the hardware architecture of the system. The second part describes the software processing of the system. The third section describes the techniques of data processing. Insuch a case, the reader can have a comprehensive understanding of the system.II.THE PRINCIPLE OF ULTRASONIC RANGING SYSTEM Considering the requirement of the actual project, we choose the ultrasound, the frequency of which is 40 kHz. Ultrasonic sensor is this kind device which can converse the sound and the electrical power, also known as ultrasonic transducer or ultrasonic probe. In certain frequency range, it can convert the electrical signal to the external ultrasonic signal or change the external ultrasonic signal to the electricalsignal. In this paper, we choose the T/R40-12 piezoelectric ultrasonic transducer. It works at the frequency of 40 kHz. Its external diameter is 12cm.Ultrasonic generator sends the ultrasonic signal at a certain time. After the ultrasonic signal reflected from the measured object, the ultrasonic receiver can receive the signal. As long as we record the time between the sending time and the receiving time, we can calculate the distance from the ultrasonic sender to the measured object. The formula for calculating the distance is:D = S/2 = V ×T /2 (1)D is the distance between the ranging device and the measured object. S is the distance which the ultrasound transports. V is the speed of the ultrasound. T is the time which the ultrasound transports. Because ultrasound is also a kind of sound wave, the speed can be affected by the temperature. So in this paper, it uses the method of temperature compensation to improve the accuracy of the system.III.HARDWARE OF THE SYSTEMThe system block diagram of ultrasonic ranging system is fig. 1. The hardware mainly includes the SCM system, the display circuit, the temperature compensation circuit and the circuit of sending and receiving ultrasound.Fig.1 The block diagram of this systemA.The circuit of sending ultrasoundThe schematic of sending ultrasound is the figure 2. The sending circuit mainly includes the inverter and the ultrasonic transducer. At first the port P1.0 of SCM is inverted, connected to one pole of the ultrasonic transducer, and then inverted again, connected to another pole of the ultrasonic transducer. By means of this push-pull method, we can improve the emission intensity of the ultrasound. Paralleling the inverter; we can increase the driving capability of outputting. The pull-up resistor R1 and R2 not only increases the driving capability of outputting the high level, but alsoincreases the damping effect of the ultrasonic transducer and shorten the time of its free oscillations.Fig.2 The circuit of sending ultrasoundB. The circuit of receiving ultrasoundThe schematic of receiving ultrasound is the fig. 3.ASIC CX20106 is used for detecting infrared.Considering the carrying frequency of CX20106 is 38kz which is very close to the frequency of the ultrasound, we design the receiving circuit by making use of CX20106.Fig.3 The circuit of receiving ultrasoundC. SCM system and the display circuitSCM STC89C52RC is the core of this ranging system, by using the 12MHz crystal oscillator to obtain a more stable clock frequency and reduce the errors. The port P1.0 of the SCM output the 40 KHz square wave that is required by the ultrasonic transducer. The external interrupt 0 is used to monitor the returning signal. The simple and practical four bit common anode LED is used for the display circuit. The segment code is driven by 74LS245, and the bit code is driven by the transistor 9012. It is shown in fig. 4.Fig.4 SCM system and the display circuitD. The circuit of temperature compensationIn the ultrasonic ranging system, a good many factors can affect the speed, such as the environmental interference, the frequency of the base pulse, etc. But the environmental temperature can be the main factor. According to the formula (2), we can see that the temperature varies from 0 ℃to 40℃, the speed of ultrasound varies from 331.4m/s to 354.85m/s. Take the room temperature 20 as the base, the speed is 343.32m/s and the rate of change is 6.83%. So the temperature factor can not be ignored. In the summer, the temperature is often more than 40 . So in the ultrasonic ranging system, it is necessary to have the temperature compensation in order to reduce the error. Nowadays most of the temperature monitoring system takes the method of temperature sensor. First of all, we convert the temperature signal to the electric signal, secondly amplify the electric signal, and thirdly convert the analog signal to the digital signal by the A/D converter. This kind of circuit is very complex and can be easily affected by the parameters of the components. For these reasons, this paper uses the temperature sensor DS18B20 and SCM to design this precisiontemperature measurement system. It can increase the accuracy of the measurement to some extent. The port DQ of the DS18B20 can directly be connected to the port P3.7 of the SCM. The circuit is shown in fig. 5.Fig.5 The circuit of temperature compensationDS18B20 is the latest digital temperature sensor from America. It is different from the traditional thermistor temperature sensors. We can directly read the measured temperature values. According to the actual requirements, we can realize the 9 or 10 bit A/D conversion through simple programming. As a result, DS18B20 can make the system has a simpler structure and higher reliability. After measuring temperature, we correct the speed of the ultrasound by the following formula: V (T) = (331.05+0.607T) (m/s) (2)In the above formula, T is the Celsius temperature of the environment ( ℃ ). IV. SYSTEM PROGRAMMINGThe programming of the ultrasonic ranging system mainly include the main program, sending subroutine, receiving subroutine, temperature compensation subroutine and display subroutine. On one hand, the assembly language is efficient and easy. On the other hand, the ranging program not only need complex calculation, but also requires a highly accurate result. So we choose assembly language to design this system.A.The main programThe main program firstly initialize the system environment, set the T0 timer for the 16-bit timer mode, Secondly set the general interrupt enable bit EA, then initialize the display port P0 and P2. After measuring the temperature value by making use of the DS18B20, the temperature compensation subroutine modifies the sound speed. At this time, it begins to call the sending subroutine. In order to avoid the direct transmission from the transmitter to the receiver, It need a delay of about 0.1ms (this is the reason for the minimum distance can be measured), then enable the external interrupt 0 to receive the return signal. As a result of using the 12MHz crystal oscillator, the timer increase one, the interval is 1us, when the main program detects that the flag is successful, it start to calculate the distance according to the timer T0, the result will be sent for LED display. Then just repeat this processing. The main program flow chart is shown in fig.6.Fig.6 The flow chart of the main programB. Sending subroutine and receiving subroutineThe sending subroutine is the role of sending about 2 ultrasonic pulses through port P1.0 (about 40kHz square wave), the pulse width is about 12us. At the same time, the timer T0 starts timing. This system makes use of the external interrupt 0 to detect the echo. Once received the echo (the pin INT0 appears a low level), it immediately access to the interrupt program, then stop the timer T0 and set the successful flag. If the echo has not been detected when the timer overflow, the timer T0 overflow interrupt will close the external interrupt 0. At the same time, it clears the successful flag. It means that this ranging processing is unsuccessful.C. Temperature compensation subroutine and display subroutineAccording to the real-time temperature detected, it calculates the speed of sound by substituting the formula (2). Display program shows the distance in the way of look-up table.V.DATA PROCESSINGNot only the processing that the circuit deal with the signal will produce a fixed delay t, but also the processing that SCM collect the signal will produce a fixed delay t. Both the above process certainly lead to some measurement errors, But this system modify the delay to reduce the ranging error. Suppose that S1 and S2 are two fixed distance. t1 and t2 are corresponding to the two fixed distance respectively(including the t factor). So S1 and S2 are actually corresponding to the time t1- t and t2- t. That is S1=0.5V(t1- t),S2=0.5V(t2- t),it can be calculated:After several measurements, we can calculate the system delay t. According to the formula (1), we can determine the distance measured. This processing can reduce the system error to some extent.VI. ACTUAL MEASUREMENT AND ANALYSISThe measurement data is shown in table 7.Table 7.The actual measurement data (unit: cm)The experimental data show that: the blind spot of the ultrasonic ranging system (the least distance that the ultrasonic sensors can detect) is 25cm. The largest distance is 372cm. While designing the program, to avoid the direct transmission of the ultrasound from the transmitter to the receiver, the program has a delay about 1.4ms, so the ultrasonic ranging system has a least ranging distance. Because the propagation of the ultrasound may cause a certain decay and the transmit power is limited, it is difficult to detect the long-rang echo. So there will be a largest measurable distance. On the other side, the temperature compensation can improve the accuracy of the measurement.VII. CONCLUSIONIn this paper, it makes use of the reflection characteristics of ultrasound. We design this kind of ranging system based on STC89C52RC. Its effective range is from 25cm to 372cm by means of non-contact measurement. Once the environment temperature changes, it improves the measurement accuracy of the system by temperature compensation circuit. After modifying the system delay, it can reduce the system latency measurement error and have a significantly improved accuracy. The results validate the rationality of the system including both the hardware and the software. This ranging system is reliable and stable. It is fully able to meet a number of high-precision occasions, such as level measurement, robot positioning, etc. ACKNOWLEDGMENTFirst of all, I thank the IEEE for providing this template, secondly I want to thank my instructor Mr. Guo, last but not least, We sincerely thank all colleagues who previously provided technical support.REFERENCES[1] WANG AI ZH. Design and reality of ultrasonic ranging system base on the microcontroller[J]. Journal of Xinzhou Teachers University, 2010,26(2): 44-46. [2] KANG Y P, LIU ZH Y, GUO X, et al. Design of high-precision ultrasonic wave ranging system[J]. Experimental Technology and Management, 2010, 27(3): 61-64. [3] WANG ZH J, SU X Y, HAN Y P. Ultrasonic distance measurement system with high precision based on AT89C51 microprocessor[J]. Sensor Technology & Applocation, 2010(1): 21-24.[4] HAN L R. A survey of methods for improving ultrasonic ranging precision[J]. Telecommunication Engineering, 2010, 50(9): 132-136.。
外文文献及翻译---超声波测距仪
原文：Ultrasonic distance meterDocument Type and Number:United States Patent 5442592Abstract:An ultrasonic distance meter cancels out the effects of temperature and humidity variations by including a measuring unit and areference unit. In each of the units, a repetitive series of pulses is generated, each having a repetition rate directly related to therespective distance between an electroacoustic transmitter and an electroacoustic receiver. The pulse trains are provided to respective counters, and the ratio of the counter outputs is utilized to determinethe distance being measured.Publication Date:08/15/1995Primary Examiner:Lobo, Ian J.BACKGROUND OF THE INVENTIONThis invention relates to apparatus for the measurement of distanceand, more particularly, to such apparatus which transmits ultrasonicwaves between two points.Precision machine tools must be calibrated. In the past, this has been accomplished utilizing mechanical devices such as calipers,micrometers, and the like. However, the use of such devices does notreadily lend itself to automation techniques. It is known that thedistance between two points can be determined by measuring the propagation time of a wave travelling between those two points. Onesuch type of wave is an ultrasonic, or acoustic, wave. When anultrasonic wave travels between two points, the distance between thetwo points can be measured by multiplying the transit time of the waveby the wave velocity in the medium separating the two points. It istherefore an object of the present invention to provide apparatusutilizing ultrasonic waves to accurately measure the distance betweentwo points.When the medium between the two points whose spacing is being measured is air, the sound velocity is dependent upon the temperature andhumidity of the air. It is therefore a further object of the,presentinvention to provide apparatus of the type described which isindependent of temperature and humidity variations.SUMMARY OF THE INVENTIONThe foregoing and additional objects are attained in accordance withthe principles of this invention by providing distance measuringapparatus which includes a reference unit and a measuring unit. The reference and measuring units are the same and each includes an electroacoustic transmitter and an electroacoustic receiver. Thespacing between the transmitter and the receiver of the reference unitis a fixed reference distance, whereas the spacing between thetransmitter and receiver of the measuring unit is the distance to be measured. In each of the units, the transmitter and receiver are coupled by a feedback loop which causes the transmitter to generate an acoustic pulse which is received by the receiver and converted into an electrical pulse which is then fed back to the transmitter, so that a repetitive series of pulses results. The repetition rate of the pulsesis inversely related to the distance between the transmitter and the receiver. In each of the units, the pulses are provided to a counter. Since the reference distance is known, the ratio of the counter outputs is utilized to determine the desired distance to be measured. Since both counts are identically influenced by temperature and humidity variations, by taking the ratio of the counts, the resultant measurement becomes insensitive to such variations.BRIEF DESCRIPTION OF THE DRAWINGSThe foregoing will be more readily apparent upon reading the following description in conjunction with the drawing in which the single FIGURE schematically depicts apparatus constructed in accordance with the principles of this invention.DETAILED DESCRIPTIONReferring now to the drawing, there is shown a measuring unit 10 and a reference unit 12, both coupled to a utilization means 14. The measuring unit 10 includes an electroacoustic transmitter 16 and an electroacoustic receiver 18. The transmitter 16 includes piezoelectric material 20 sandwiched between a pair of electrodes 22 and 24. Likewise, the receiver 18 includes piezoelectric material 26 sandwiched between a pair of electrodes 28 and 30. As is known, by applying an electric field across the electrodes 22 and 24, stress is induced inthe piezoelectric material 20. If the field varies, such as by the application of an electrical pulse, an acoustic wave 32 is generated.As is further known, when an acoustic wave impinges upon the receiver 18, this induces stress in the piezoelectric material 26 which causesan electrical signal to be generated across the electrodes 28 and 30. Although piezoelectric transducers have been illustrated, other electroacoustic devices may be utilized, such as, for example, electrostatic, electret or electromagnetic types.As shown, the electrodes 28 and 30 of the receiver 18 are coupled to the input of an amplifier 34, whose output is coupled to the input of a detector 36. The detector 36 is arranged to provide a signal to the pulse former 38 when the output from the amplifier 34 exceeds a predetermined level. The pulse former 38 then generates a trigger pulse which is provided to the pulse generator 40. In order to enhance the sensitivity of the system, the transducers 16 and 18 are resonantly excited. There is accordingly provided a continuous wave oscillator 42 which provides a continuous oscillating signal at a fixed frequency,preferably the resonant frequency of the transducers 16 and 18. This oscillating signal is provided to the modulator 44. To effectivelyexcite the transmitter 16, it is preferable to provide several cyclesof the resonant frequency signal, rather than a single pulse or single cycle. Accordingly, the pulse generator 40 is arranged, in response to the application thereto of a trigger pulse, to provide a control pulseto the modulator 44 having a time duration equal the time duration of a predetermined number of cycles of the oscillating signal from the oscillator 42. This control pulse causes the modulator 44 to pass a "burst" of cycles to excite the transmitter 16.When electric power is applied to the described circuitry, there is sufficient noise at the input to the amplifier 34 that its outputtriggers the pulse generator 40 to cause a burst of oscillating cyclesto be provided across the electrodes 22 and 24 of the transmitter 16. The transmitter 16 accordingly generates an acoustic wave 32 which impinges upon the receiver 18. The receiver 18 then generates an electrical pulse which is applied to the input of the amplifier 34,which again causes triggering of the pulse generator 40. This cycle repeats itself so that a repetitive series of trigger pulses results atthe output of the pulse former 38. This pulse train is applied to the counter 46, as well as to the pulse generator 40.The transmitter 16 and the receiver 18 are spaced apart by the distance "D" which it is desired to measure. The propagation time "t" for an acoustic wave 32 travelling between the transmitter 16 and the receiver 18 is given by: t=D/V swhere V s is the velocity of sound in the air between the transmitter16 and the receiver 18. The counter 46 measures the repetition rate of the trigger pulses, which is equal to 1/t. Therefore, the repetitionrate is equal to V s /D. The velocity of sound in air is a function ofthe temperature and humidity of the air, as follows: ##EQU1## where T is the temperature, p is the partial pressure of the water vapor, H isthe barometric pressure, Γ w and Γ a are the ratio of constantpressure specific heat to constant volume specific heat for water vapor and dry air, respectively. Thus, although the repetition rate of the trigger pulses is measured very accurately by the counter 46, the sound velocity is influenced by temperature and humidity so that the measured distance D cannot be determined accurately.In accordance with the principles of this invention, a reference unit12 is provided. The reference unit 12 is of the same construction asthe measuring unit 10 and therefore includes an electroacoustic transmitter 50 which includes piezoelectric material 52 sandwiched between a pair of electrodes 54 and 56, and an electroacoustic receiver 58 which includes piezoelectric material 60 sandwiched between a pair of electrodes 62 and 64. Again, transducers other than thepiezoelectric type can be utilized. The transmitter 50 and the receiver58 are spaced apart a known and fixed reference distance "D R ". The electrodes 62 and 64 are coupled to the input of the amplifier 66,whose output is coupled to the input of the detector 68. The output ofthe detector 68 is coupled to the pulse former 70 which generatestrigger pulses. The trigger pulses are applied to the pulse generator72 which controls the modulator 74 to pass bursts from the continuous wave oscillator 76 to the transmitter 50. The trigger pulses from thepulse former 70 are also applied to the counter 78.Preferably, all of the transducers 16, 18, 50 and 58 have the same resonant frequency. Therefore, the oscillators 42 and 76 both operateat that frequency and the pulse generators 40 and 72 provide equal width output pulses.In usage, the measuring unit 10 and the reference unit 12 are in close proximity so that the sound velocity in both of the units is the same. Although the repetition rates of the pulses in the measuring unit 10and the reference unit 12 are each temperature and humidity dependent, it can be shown that the distance D to be measured is related to the reference distance D R as follows: i D=D R (1/t R )/(1/t)where t R is the propagation time over the distance D R in thereference unit 12. This relationship is independent of both temperature and humidity.Thus, the outputs of the counters 46 and 78 are provided as inputs tothe microprocessor 90 in the utilization means 14. The microprocessor90 is appropriately programmed to provide an output which is proportional to the ratio of the outputs of the counters 46 and 78,which in turn are proportional to the repetition rates of therespective trigger pulse trains of the measuring unit 10 and the reference unit 12. As described, this ratio is independent oftemperature and humidity and, since the reference distance D R is known, provides an accurate representation of the distance D. The utilization means 14 further includes a display 92 which is coupled toand controlled by the microprocessor 90 so that an operator can readily determine the distance D.Experiments have shown that when the distance between the transmitting and receiving transducers is too small, reflections of the acousticwave at the transducer surfaces has a not insignificant effect which degrades the measurement accuracy. Accordingly, it is preferred that each transducer pair be separated by at least a certain minimum distance, preferably about four inches.译文：超声波测距仪文件类型和数目：美国专利5442592摘要：提出了一种超声波测距仪来抵消温度和湿度的变化，包括测量单元和参考标准。
汽车倒车测距仪外文文献翻译
汽车倒车测距仪外文文献及翻译(文档含中英文对照即英文原文和中文翻译) 汽车倒车测距仪的设计摘要本文介绍了汽车倒车测距仪的功能确定、测距原理、设计方法及技术实现,介绍了汽车与障碍物间距离测量的信号处理方法。
论述了如何有效地测出并实时地显示出汽车与障碍物的距离,规定了各种不同的报警类型,对于相关类测量系统设计有一定的参考意义。
关键词超声单片机测距信号调理随着汽车产业的发展和人们生活水平的不断提高,汽车的数量逐年增加,例如1999 年,我国的汽车年产量已突破了180 万辆,造成公路、街道、停车场、车库等越来越拥挤不堪。
汽车驾驶员越来越为车的安全担心了,其中倒车就是一个典型,在繁忙、拥挤、狭窄的地方倒车时,驾驶员即得“瞻前”,又要“顾后”,往往一不小心,就会与汽车尾部障碍物发生碰撞事件。
经过调查,对绝大部分非职业汽车驾驶员都希望有一种能发现汽车尾部障碍物的“后视眼”———倒车测距仪,因此我们设计了一种经济实惠的汽车倒车测距仪,可以解决驾驶员的“后顾之忧”。
1 汽车倒车测距仪的功能指标确定经过对许多汽车驾驶员的调查,确定主要功能指标如下:(1) 最大测距5. 00 米,最小测距0. 35 米,实时数字显示测得距离,显示分辨率0. 01 米;(2) 超过5. 00 米为溢出,仅显示小数点,当距离小于0. 35 米时,显示为0. 00 ,表示很危险;(3) 灯光报警:当距离小于0. 60 米时,报警指示灯亮;(4) 声音报警:当距离小于1. 20 米时蜂鸣器发出间隔频率为1 Hz 的Bi ⋯Bi ⋯声,当距离小于0. 90米时蜂鸣器发出间隔频率为2 Hz 的Bi ⋯Bi ⋯声,当距离小于0. 60 米时蜂鸣器发出间隔频率为5 Hz 的Bi ⋯Bi ⋯声,当距离小于0. 35 米时蜂鸣器连续发出BiBiBi 声。
2 测距原理根据声音传播过程中遇到障碍物会发生反射这一原理可以测量距离,超声波测距也是这个原理,即用超声脉冲发射和接收其回波之间的时间差来计算距离,计算公式如下:V = 331. 5 + 0. 607 T式中:V ———超声波在空气中传播速度,其单位为米/ 秒,T ———环境温度,单位为℃。
英文翻译
文献翻译题目超声波测距器的设计原理学生姓名李腾飞专业班级电子信息工程06-1班学号 200601030122 院（系）电气信息工程学院指导教师张勇完成时间 2010年6月8日英文原文Ultrasonic range finder designThis article described the three directions (before, left, right) ultrasonic ranging system is to understand the front of the robot, left and right environment to provide a movement away from the information. (Similar to GPS Positioning System)A principle of ultrasonic distance measurement1, the principle of piezoelectric ultrasonic generatorPiezoelectric ultrasonic generator is the use of piezoelectric crystal resonators to work. Ultrasonic generator, the internal structure as shown in Figure 1, it has two piezoelectric chip and a resonance plate. When it's two plus pulse signal, the frequency equal to the intrinsic piezoelectric oscillation frequency chip, the chip will happen piezoelectric resonance, and promote the development of plate vibration resonance, ultrasound is generated. Conversely, if the two are not inter-electrode voltage, when the board received ultrasonic resonance, it will be for vibration suppression of piezoelectric chip, the mechanical energy is converted to electrical signals, then it becomes the ultrasonic receiver.2, the principle of ultrasonic distance measurementUltrasonic transmitter in a direction to launch ultrasound, in the moment to launch the beginning of time at the same time, the spread of ultrasound in the air, obstacles on his way to return immediately, the ultrasonic reflected wave received by the receiver immediately stop the clock. Ultrasound in the air as the propagation velocity of 340m / s, according to the timer records the time t, we can calculate the distance between the launch distance barrier (s), that is: s = 340t / 2Ultrasonic Ranging System for the Second Circuit Design System is characterized by single-chip microcomputer to control the use of ultrasonic transmitter and ultrasonic receiver since the launch from time to time, single-chip selection of 8751, economic-to-use, and the chip has 4K of ROM, to facilitate programming. Circuit schematic diagram shown in Figure 2. Draw only thefront range of the circuit wiring diagram, left and right in front of Ranging Ranging circuits and the same circuit, it is omitted.1,40 kHz ultrasonic pulse generated with the launchRanging system using the ultrasonic sensor of piezoelectric ceramic sensors UCM40, its operating voltage of the pulse signal is 40kHz, which by the single-chip implementation of the following procedures to generate.mov 14h, # 12h ultrasonic firing continued 200mscpl p1.0 output 40kHz square wavenopnopnopdjnz 14h, hereretRanging in front of single-chip termination circuit P1.0 input port, single chip implementation of the above procedure, the P1.0 port in a 40kHz pulse output signal, after amplification transistor T, the drive to launch the first ultrasonic UCM40T, issued 40kHz ultrasonic pulse, and the continued launch of 200ms. Ranging the right and the left side of the circuit, respectively, then input port P1.1 and P1.2, the working principle and circuit in front of the same location.2, reception and processing of ultrasonicUsed to receive the first launch of the first pair UCM40R, the ultrasonic pulse modulation signal into an alternating voltage, the op-amp amplification IC1A and after polarization IC1B to IC2. IC2 is locked loop with audio decoder chip LM567, internal voltage-controlled oscillator center frequency of f0 = 1/1.1R8C3, capacitorC4 determine their target bandwidth. R8-conditioning in the launch of the carrier frequency on the LM567 input signal is greater than 25mV, the output from the high jump 8 feet into a low-level, as interrupt request signals to the single-chip processing. Ranging in front of single-chip termination circuit output port INT0 interrupt the highest priority, right or left location of the output circuit with output gate IC3Aaccess INT1 port single-chip, while single-chip P1.3 and P1. 4 received input IC3A, interrupted by the process to identify the source of inquiry to deal with, interrupt priority level for the first left right after. Part of the source code is as follows:push pswpush accclr ex1 related external interrupt 1jnb p1.1, right ranging from right to interrupt servicejnb p1.2, left to the left ranging circuit interrupt serviceSETB EX1 open external interrupt 1pop accpop pswretiAjmp ReturnAjmp Return3, the calculation of ultrasonic propagation timeWhen you start firing at the same time start the single-chip circuitry within the timer T0, the use of timer counting function records the time and the launch of ultrasonic reflected wave received time. When you receive the ultrasonic reflected wave, the receiver circuit outputs a negative jump in the end of INT0 or INT1 interrupt request generates a signal, single-chip microcomputer in response to external interrupt request, the implementation of the external interrupt service subroutine, read the time difference, calculating the distance . Some of its source code is as follows:PUSH PSWPUSH ACCCLR EX0 related external interrupt 0MOV R7, TH0 read the time valueMOV R6, TL0CLR CMOV A, R6SUBB A, # 0BBH calculate the time differenceMOV 31H, A storage resultsMOV A, R7SUBB A, # 3CHMOV 30H, ASETB EX0 open external interrupt 0POP ACCPOP PSWRETIthe ultrasonic ranging system software designSoftware is divided into two parts, the main program and interrupt service routine, shown in Figure 3 (a) (b) (c) below. Completion of the work of the main program is initialized, each sequence of ultrasonic transmitting and receiving control. Interrupt service routines from time to time to complete three of the rotation direction of ultrasonic launch, the main external interrupt service subroutine to read the value of completion time, distance calculation, the results of the output and so on.CONCLUSIONSRequired measuring range of 30cm ~ 200cm objects inside the plane to do a number of measurements found that the maximum error is 0.5cm, and good reproducibility. Single-chip design can be seen on the ultrasonic ranging system has a hardware structure is simple, reliable, small features such as measurement error. Therefore, it can be used not only for mobile robot can be used in other detection systems.英文翻译超声波测距器的设计本文所介绍的三方向（前、左、右）超声波测距系统，就是为机器人了解其前方、左侧和右侧的环境而提供一个运动距离信息。
文献翻译-超声测距系统设计
毕业设计（论文）英文资料翻译Ultrasonic ranging system design系别专业班级学生姓名学号指导教师中文翻译超声测距系统设计摘要：超声测距技术在工业现场、车辆导航、水声工程等领域都具有广泛的应用价值，目前已应用于物位测量、机器人自动导航以及空气中与水下的目标探测、识别、定位等场合。
因此，深入研究超声的测距理论和方法具有重要的实践意义。
为了进一步提高测距的精确度，满足工程人员对测量精度、测距量程和测距仪使用的要求，本文研制了一套基于单片机的便携式超声测距系统。
关键词：超声波，测距仪，单片机1.前言随着科技的发展，人们生活水平的提高，城市发展建设加快，城市给排水系统也有较大发展，其状况不断改善。
但是，由于历史原因合成时间住的许多不可预见因素，城市给排水系统，特别是排水系统往往落后于城市建设。
因此，经常出现开挖已经建设好的建筑设施来改造排水系统的现象。
城市污水给人们带来了困扰，因此箱涵的排污疏通对大城市给排水系统污水处理，人们生活舒适显得非常重要。
而设计研制箱涵排水疏通移动机器人的自动控制系统，保证机器人在箱涵中自由排污疏通，是箱涵排污疏通机器人的设计研制的核心部分。
控制系统核心部分就是超声波测距仪的研制。
因此，设计好的超声波测距仪就显得非常重要了。
2.SCM描述微控制器(MCU)是一种单片计算机。
这是一种强调自给自足和成本效益形成鲜明对比的通用微处理器（PC）。
现在使用的大多数的计算机系统是嵌入到其他机器中，如电话、时钟、电器、汽车和基础设施。
嵌入式系统通常对内存和程序长度的要求很小并且可能需要简单但不寻常的输入/输出系统。
例如，大多数嵌入式系统缺乏键盘，屏幕，磁盘、打印机或其他可辨认的个人计算机的I/O设备。
他们可能控制电动机、继电器或电压和阅读开关、可变电阻或者其他电子设备。
通常情况下，人类可读的唯一的I/O设备是一个发光二极管，严重的甚至可以消除这种成本或权力约束。
与通用CPU相比，微控制器没有一个地址总线或一个数据总线，因为他们整合了所有的内存和非易失性内存相同的芯片CPU。
利用超声波测距系统和声纳
利用超声波测距系统和声纳回波图对障碍物探测的分析Akihisa OHY A, Takayuki OHNO and Shin’ichi YUTA摘要从超声波传感器获取的信息受传感系统特性如灵敏度，方向性等影响。
为了探讨传感系统特性对超声波传感器获取信息的影响，我们建立了两个特性互不相同的超声波测距系统，并对这两个系统相互借鉴，研究，以检测它们的性能如障碍物检测性及合成的生纳回波图。
关键词：超声波感测，障碍物检测，声纳回波图1.简介对于移动机器人，无论是否具有环境地图，它都必须具有识别环境的功能来寻找不可预知的障碍物和机器人可以通过的路径。
至于射程传感器，它可以测量与物体间的距离，超声波传感器普遍用于移动机器人中，因为它体积小，价格低廉，更易于距离的计算。
目前的超声波传感器系统通常使用的传播时间计算距离（传播时间）方法。
该传感器系统到反射物（障碍物）的距离l通过公式/2计算。
其中，c是超声波l ct在空气中的传播速度，t是往返传播时间，即为超声波从发射到接收的时间（如图1）。
传播时间法在回波幅度首次超过临界值后产生一个范围值。
尽管像这样的方法非常简单，然而从超声波传感器获取的信息仍受传感系统特性的影响。
例如它的环境等。
为了探讨传感系统特性对超声波传感器获取信息的影响，我们建立了两个特性互不相同的超声波测距系统，并对这两个系统相互借鉴，研究，检测他们的性能如障碍物检测性及合成的生纳回波图。
图1：TOF原理图在第二部分中，我们将会介绍两个我们开发的超声波测距系统。
该测距系统对障碍物检测的可行性会在第三部分验证。
生纳回波图的制作使用在第四部分，最后将在第五部分得出结论。
2.两个超声波测距系统反射波的模型如图2所示，在图中我们能看到两个障碍物A和B。
随着超声波的衰减和传播，反射回波幅度越来越远，从反射回波中分析出的障碍物就越来越小（甚至实际上两个障碍物的尺寸大小、特性等都是一样的）。
由于我们使用的是压电式超声波感测器，该超声波传感器的发射器和接收器是相互独立的。
毕业设计论文 外文文献翻译 超声波测距 中英文对照
毕业设计论文外文文献翻译超声波测距中英文对照The Circuit Design of UltrasonicRanging System超声波测距系统的电路设计Ultrasonic Distance Meter超声波测距仪姓名:专业: 测控技术与仪器学号: 2007071071指导教师姓名,职称,:The Circuit Design of Ultrasonic Ranging SystemThis article described the three directions (before, left, right) ultrasonic ranging system is to understand the front of the robot, left and right environment to provide a movement away from the information. (Similar to GPS Positioning System)A principle of ultrasonic distance measurement1, the principle of piezoelectric ultrasonic generatorPiezoelectric ultrasonic generator is the use of piezoelectriccrystal resonators to work. Ultrasonic generator, the internal structure as shown in Figure 1, it has two piezoelectric chip and a resonance plate. When it's two plus pulse signal, the frequency equal to the intrinsic piezoelectric oscillation frequency chip, the chip will happen piezoelectric resonance, and promote the development of plate vibrationresonance, ultrasound is generated. Conversely, if the two are notinter-electrode voltage, when the board received ultrasonic resonance,it will be for vibration suppression of piezoelectric chip, the mechanical energy is converted to electrical signals, then it becomes the ultrasonic receiver.2, the principle of ultrasonic distance measurementUltrasonic transmitter in a direction to launch ultrasound, in the moment to launch the beginning of time at the same time, the spread of ultrasound in the air, obstacles on his way to return immediately, the ultrasonic reflected wave received by the receiver immediately stop the clock. Ultrasound in the air as the propagation velocity of 340m / s, according to the timer records the time t, we can calculate the distance between the launch distance barrier (s), that is: s = 340t / 2 Ultrasonic Ranging System for the Second Circuit DesignSystem is characterized by single-chip microcomputer to control the use of ultrasonic transmitter and ultrasonic receiver since the launch from time to time, single-chip selection of 8751, economic-to-use, and the chip has 4K of ROM, to facilitate programming. Circuit schematic diagram shown in Figure 2. Draw only the front range of the circuit wiring diagram, left and right in front of Ranging circuits and the same circuit, it is omitted.1,40 kHz ultrasonic pulse generated with the launchRanging system using the ultrasonic sensor of piezoelectric ceramic sensors UCM40, its operating voltage of the pulse signal is 40kHz, whichby the single-chip implementation of the following procedures to generate.puzel: mov 14h, # 12h; ultrasonic firing continued 200mshere: cpl p1.0; output 40kHz square wavenop;nop;nop;djnz 14h, here;retRanging in front of single-chip termination circuit P1.0 input port, single chip implementation of the above procedure, the P1.0 port in a40kHz pulse output signal, after amplification transistor T, the drive to launch the first ultrasonic UCM40T, issued 40kHz ultrasonic pulse, and the continued launch of 200ms. Ranging the right and the left side of the circuit, respectively, then input port P1.1 and P1.2, the working principle and circuit in front of the same location.2, reception and processing of ultrasonicUsed to receive the first launch of the first pair UCM40R, the ultrasonic pulse modulation signal into an alternating voltage, the op-amp amplification IC1A and after polarization IC1B to IC2. IC2 is locked loop with audio decoder chip LM567, internal voltage-controlledoscillator center frequency of f0 = 1/1.1R8C3, capacitor C4 determine their target bandwidth. R8-conditioning in the launch of the carrier frequency on the LM567 input signal is greater than 25mV, the outputfrom the high jump 8 feet into a low-level, as interrupt request signals to the single-chip processing.Ranging in front of single-chip termination circuit output port INT0 interrupt the highest priority, right or left location of the output circuit with output gate IC3A access INT1 port single-chip, whilesingle-chip P1.3 and P1. 4 received input IC3A, interrupted by the process to identify the source of inquiry to deal with, interruptpriority level for the first left right after. Part of the source codeis as follows:receive1: push pswpush accclr ex1; related external interrupt 1jnb p1.1, right; P1.1 pin to 0, ranging from right to interrupt service routine circuitjnb p1.2, left; P1.2 pin to 0, to the left ranging circuit interrupt service routinereturn: SETB EX1; open external interrupt 1pop accpop pswretiright: ...; right location entrance circuit interrupt serviceroutineAjmp Returnleft: ...; left Ranging entrance circuit interrupt service routineAjmp Return4, the calculation of ultrasonic propagation timeWhen you start firing at the same time start the single-chipcircuitry within the timer T0, the use of timer counting function records the time and the launch of ultrasonic reflected wave received time. When you receive the ultrasonic reflected wave, the receivercircuit outputs a negative jump in the end of INT0 or INT1 interrupt request generates a signal, single-chip microcomputer in response to external interrupt request, the implementation of the external interrupt service subroutine, read the time difference, calculating the distance . Some of its source code is as follows:RECEIVE0: PUSH PSWPUSH ACCCLR EX0; related external interrupt 0MOV R7, TH0; read the time valueMOV R6, TL0?CLR CMOV A, R6SUBB A, # 0BBH; calculate the time differenceMOV 31H, A; storage resultsMOV A, R7SUBB A, # 3CHMOV 30H, ASETB EX0; open external interrupt 0POP ACCPOP PSWRETIFourth, the ultrasonic ranging system software designSoftware is divided into two parts, the main program and interrupt service routine, shown in Figure 3 (a) (b) (c) below. Completion of the work of the main program is initialized, each sequence of ultrasonic transmitting and receiving control.Interrupt service routines from time to time to complete three ofthe rotation direction of ultrasonic launch, the main external interrupt service subroutine to read the value of completion time, distance calculation, the results of the output and so on.V. CONCLUSIONSRequired measuring range of 30cm ~ 200cm objects inside the plane to do a number of measurements found that the maximum error is 0.5cm, and good reproducibility. Single-chip design can be seen on the ultrasonic ranging system has a hardware structure is simple, reliable, small features such as measurement error. Therefore, it can be used not only for mobile robot can be used in other detection systems.Thoughts: As for why the receiver do not have the transistoramplifier circuit, because the magnification well, CX20106 integrated amplifier, but also with automatic gain control level, magnification to 76dB, the center frequency is 38k to 40k, is exactly resonant ultrasonic sensors frequency.超声波测距系统的电路设计本文所介绍的三方向(前、左、右)超声波测距系统，就是为机器人了解其前方、左侧和右侧的环境而提供一个运动距离信息。
外文翻译----超声波距离传感器
英文原文：Ultrasonic distance sensorDesign Principles:Ultrasonic sensor is developed from the use of the characteristics of ultrasonic sensors.Higher frequency ultrasound is a mechanical acoustic waves, the transducer excitation voltage of the chip occurs in the vibration, and it has a high frequency, short wavelength, diffraction is small, especially the direction of good, to be the ray and the orientationcommunication and so on.Ultrasound on liquids and solids through a great ability, especially in opaque solids in the sun, which can penetrate tens of meters in depth.Ultrasonic impurities or sub-interface will encounter a significant reflection reflection into the echo formation, hit moving objects can produce the Doppler effect.Therefore widely used in industrial ultrasonic inspection, defense, biomedical and other aspects of the ultrasound as a means of detection, must generate and receive ultrasound ultrasound.To fulfill this function the device is ultrasonic sensors, traditionally known as the ultrasonic transducer or ultrasonic probe.The main performance indicators of ultrasonic sensors:Ultrasound probe is the core of its plastic jacket or a piece of metal in the piezoelectric jacket.Constitute the chip can have many kinds of materials.Chip size, such as diameter and thickness also vary, so the performance of each probe is different, we used to know it in advance before the performance.The main performance indicators of ultrasonic sensors include: (1) operating frequency.Frequency is the resonant frequency of the piezoelectric wafer.When added to the AC voltage across it, and the frequency of the resonant frequency of the chip are equal, the maximum energy output, sensitivity is highest.(2) operating temperature.Since the Curie point of piezoelectric materials generally high, particularly when using the power of diagnostic ultrasound probe small, so the temperature is relatively low, you can work long hours without producing failure.Medical ultrasound probe temperature is relatively high, requiring a separate cooling device.(3) sensitivity.Depends primarily on manufacturing the chip itself.Electromechanical coupling coefficient, high sensitivity; the other hand, low sensitivity.Structure and Working Principle:When voltage is applied to piezoelectric ceramic, it will with the voltage and frequency of changes in the mechanical deformation.On the other hand, when the vibration of piezoelectric ceramics, it will generate a ing this principle, when given by the two piezoelectric ceramic or a piezoelectric ceramic and a vibrator, sheet metal, the so-called bimorph element called the imposition of an electricalsignal, it will emit ultrasonic vibration due to bending.Conversely, when applied to the bimorph ultrasonic devices, it will generate an electrical signal.Based on the above role, it can be used as a piezoelectric ceramic ultrasonic sensors.Such as ultrasonic sensors, a compound vibrator was flexibility on a fixed base.The vibrator is a composite resonator, and by a metal plate and a piezoelectric bimorph element consisting of a combination vibrator.Resonator and trumpets the purpose of effective radiation generated by the ultrasonic vibrations, and can effectively make ultrasonic vibrator gathered in a central location.Outdoor uses ultrasonic sensors must have a good seal in order to prevent dew, rain and dust intrusion.Piezoelectric ceramic is fixed on the top of the metal box inside the body.Base fixed in the open end of box, and covered with resin.Of ultrasonic sensors for industrial robots, the requirements to achieve an accuracy of 1mm, and has strong ultrasonic ponents using conventional bimorph bending vibration of the vibrator, in the case of frequencies above 70kHz, it is impossible to achieve this purpose.Therefore, in the high-frequency probe, you must use the vertical thickness vibration mode piezoelectric ceramic.In this case, the acoustic impedance of piezoelectric ceramics and the air becomes very important match.Acoustic impedance of piezoelectric ceramic 2.6 × 107kg/m2s, while the acoustic impedance of air is 4.3×102kg/m2s.5different power piezoelectric vibration will result in substantial losses of radiation on the surface.Adhesion of a special material on the piezoelectric ceramic, matching layers, as the sound can be achieved with air impedance match.This structure allows up to several hundred kHz ultrasonic sensors in the frequency of the circumstances, still be able to work properly.Ultrasonic distance sensor technology and application of the principle:Ultrasonic distance sensor can be widely used in Level (level) monitoring, robot collision avoidance, a variety of ultrasonic proximity switches, and related areas such as anti-theft alarm, reliable, easy installation, waterproof, small launch angle, high sensitivity,display instruments to facilitate connections with industry, also provides a larger probe launch angle.1, ultrasonic range finder: ultra-high energy acoustic ranging techniques to ultrasonic distance measurement techniques have been major breakthroughs, it not only broadens the applications of ultrasonic distance measurement technology (for very poor working conditions), and the use of smart regulation technology,greatly improve the reliability of ultrasonic products, and performance indicators, allowing users to worry about without looking back.Excellent echo processing technology ,5-50KHZ of ultra high strength level meter wave frequency to the maximum range up to 120 meters for medium temperature is -20℃-+175℃.Intelligent automatic adjustment made wave frequency, automatic temperature compensation function to work more stable and reliable.HpAWK series also has a flexible work (the power supply for 12VDC, 24VDC, 110V AC, 220V AC; two / three / four-wire system can be freely combined in the same instrument.It also has advanced remote GSM, CDMA, Internet debugging features, enabling users to readily available technical support.中文译文:超声波距离传感器设计原理:超声波传感器是利用超声波的特性研制而成的传感器。
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=======大学本科生毕业设计外文文献及中文翻译文献题目： ULTRASONIC RANGING SYSTEM 文献出处：United States Patent译文题目：超声波测距系统学生：指导教师：专业班级：自动化11-4 学号： 110601140416电气信息工程学院2014年5月1日超声波测距系统摘要超声波测距系统，是指选择性地激励一个变压器，使之产生换能器驱动信号。
超声换能器发射的超声波脉冲用于响应驱动信号然后接收到一个在超声波信号发出之后的回波信号。
分路开关接在变压器的绕组上，当超声波信号的传输在允许的近距离范围内达到一个稳定的等级，分路开关选择性的闭合来阻止蜂鸣器报警。
第1章发明背景像在宝丽来相机中应用的可用范围测试系统，它们都是准确而且可靠的，但都不适用于近距离测距，举个例子，2到3英寸的距离内就不适用，所以他们在9英寸甚至更远的距离测距是可靠的。
它们可以应用在很多的应用程序中，但不适用于可移动机器人领域内。
机器人通常必须通过门口只有两三英寸的间隙，如果当可移动机器人被操作于避障模式下通过狭小空间，可能机器人的规避路径过于狭窄，此外,规避动作应该使偏指定的路径距离最小化。
近距离测距不用于超声波系统的一个原因是，近距离输出脉冲输出太长以至于它重叠在回波脉冲上，即使输出脉冲缩短,输出脉冲仍然重叠回波脉冲，因为声音紧跟着输出脉冲。
备中产生的回波信号脉冲的范围为100毫伏，但设置传感器响应所必需的电路回声脉冲是大约150伏到300伏之间。
因此即使是最小的声波也会盖过回声信号。
事实上,dual-diode钳位电路用于将150伏降低到二极管的击穿电压，即0.7伏特。
但是这700毫伏足以盖过100毫伏的回波信号。
目前系统需要50毫秒将300伏特的峰值发射电压降到0.7伏特，且额外需要500到600毫秒的时间将它稳定在1毫伏范围。
第2章发明总结本发明可以提供一种改进的超声波测距系统。
本发明也可以提供一个改进的多通道超声波测距系统。
本发明也可以提供一种装有改进的超声波测距系统的车辆移动机器人。
本发明也能使超声波测距的范围及其精准。
本发明也可以为超声波测距系统提供更短的脉冲输出。
本发明可以使超声波测距系统的铃声远低于回波信号的水平。
同时也可以使超声波测距系统所有铃声低于回波信号的速度变得非常快，并在回波信号出现之前完成这个操作。
这个发明可以通过选择性的分流传动变压器的绕组从而快速的抑制振铃换能器的驱动信号来实现真正的短距离测距系统，这些都明确后，窗口就会迅速的返回短程回波。
这个超声波测距系统包括一个变压器并且通过选择性的方法激励变压器产生一个换能器驱动信号。
这是一个可以发射超声波脉冲响应的驱动信号，同时在收到回波脉冲中生成一个回波信号的超声波换能器。
阻尼法包括连着并联开关的绕组变压器，并且这个方法可以选择性的关闭并联开关，同时快速的阻尼振铃后超声波脉冲的传输水平会大大低于回波信号允许的水平。
主要的体现为并联开关连接低压绕组变压器并且换能器是耦合高压绕组的变压器，可能会有一种降低方式来降低高压绕组和回波信号的水平高度。
该系统还包括拥有能生成一系列回波信号的方法。
这意味着生成的一系列信号的同时还需要整合回波信号的积分电路。
当比较器提供一个复位信号时，这是积分电路输出达到预定的水平。
并且一个控制电路所设定的驱动信号在复位时，比较器会输出当积分电路达到预定水平时提供的一系列的信号的设置时间和重置时间。
超声波测距系统可能是一个频道多通道的系统，同时整个系统可能是一个车辆或者是一个移动机器人。
输出的脉冲也可以是一个或者许多个脉冲。
第3章运用超声波测距的比较好的例子其他对象、特点和优势会在下面的描述中还有图纸中得以体现，其中：图一是一个机器人的侧轴投影，这个发明结合了超声波测距系统；图二是图一的分层视图，其中机器人有部分元件删除；图三是图一、图二中所示装置的电子模块框图；图四A图一所示机器人的超声波、红外和微波传感器的概念图；图四B是侧视图，图A是俯视图；图五A图三所示超声波模块中的传感器控制模块和超声波传感器的原理框图；图五B是控制超声波模块中的微处理器的软件的流程图图六是一个的电子机器人底盘的俯视图，显示了图一图二的传感器控制模块、传感器、超声波模块和电源；图七A是如图五图六所示的传感器控制模块的详细框图；图七B是显示图七A各种信号关系的时序图；图八是图七的更详细的变压器驱动原理图；如图一所示，机器人10，这个发明包括头部12，基座14，它们可在三个轮子上移动，这三个轮子中只有16和18是可见的，轮子安装在三个可操作的座上，其中只有22和20是可见的，有24个超声换能器24像是宝丽来相机上安装的静电传感器，它们等距的围绕在基座14上，每两个夹角15度。
在脖子26上有六个被动红外探测器28、30、32、34、36、38，其中只有28和30是可见的。
这些探测器夹角都是60度，是等距的，可能是ARITECH的dr-321型号。
紧上方是两个指挥带50、52，他们是用来给充电臂机器人电池充电的。
机头部分12安装到底座14上在底座14中轴线上，可旋转。
机头12上携带一个射频天线65，用于发送和接收通信信号的基本位置。
机头部分12还包含一个红外传感器68，它被用在近红外区感应辐射，例如904纳米灯塔的LED灯62，其中一个或多个被安装在墙上用来保护机器人10还有协助机器人10定位和引导机器人10在该地区巡逻。
超声换能器66类似于换能器24用于操纵换能器24避免超过范围68。
同样也有一个被动红外传感器68和传感器28-38。
微波传输和接收天线70和电视摄像机72在明显的入侵发生时也会启动，他们也包含在机头12内。
基座14主要包括可携带三个12V凝胶细胞电池82的底盘，这种电池只是其中的一种，在充满电的时候可以操控机器人12个小时或更长的时间。
带有轮子16,18的卡车20,22，轮子分别从底盘悬挂80,同时安装上直角驱动器84，垂直驱动轴86和输入输出水平转动轴88。
操作滑轮90，通过皮带94连接车轮16上垂直轴86的驱动轴96和与其对应的驱动轴98，由各自的驱动链轮100,102,104或者滑轮并且安装在底盘。
机器人上装有一个带有电机110的编码器111用来监测机器人的速度。
一个惰轮112给皮带106提供适当的张力。
三个额外的轴，只显示其中的99，同心轴86,96,98。
并且分别由第二组滑轮或者是链轮120,122,124驱动用传动皮带126驱动链轮驱动转相关电动机130安装在底盘80。
惰轮131用于维护皮带126张力。
编码器132与电机130提供输出指示性转向的位置。
转向电机穿过滑轮128连接扩展轴134的顶部的一个多元化的法兰安装孔134。
在电子地盘136上安装三个螺母，电子底盘134上开通三个洞138容纳三个长的螺母144。
电子机箱140包含所有的电子电路板和组件。
例如项目中显示的基础组件，也包括下文中描述的状态模块。
当电子底盘140和脖子26被安装在他们各自的固定位置，扩展轴134和法兰136相关的结构通过电子底盘140的中心孔160和脖子26的开口处，头版170可能通过螺钉172安装在法兰螺纹孔138处。
这样，整个头部都能在转向电动机130随卡夹轮子同步转动。
除了主要的微波传感器70还有三个额外的微波传感器190、330、332，只有其中一个。
190清晰可见，距离头版170 90的距离安装在外壳192、194、196上。
外壳194直接对着头部后面面向前方的微波传感器70，传感器334还包含一个传感器，不可见，这个传感器和红外传感器68相同。
盖板200保护在头部170里面的电路板。
所有的电气互联头12和基座14之间都通过滑轮连接在滑轮单元202上穿过基座14的安装扩展轴134。
如图三头部12包括三个电子部分：信标模块210，超声波模块212，入侵检测模块214。
信标模块210响应头部的红外传感器60来确定是机器人的角信标64。
这个角是通过滑轮装置202连接在主CPU218上的。
超声波模块212对超声换能器66进行响应，在CPU218上的总线216提供范围信息。
入侵者检测模块214响应四个微波传感器70、190、330、332，还有两个红外传感器68、334证明是否有入侵发生，这些事件通过主CPU内的报警确认单位220确认。
身体部分14，包括状态模块222、移动模块224，超声波模块226还有CPU218。
状态模块222响应六个传感器28-38来提供入侵的迹象。
状态模块222也可以监控火灾和烟雾传感器，机器人中的诊断传感器，以及化学和气味传感器以及其他类型的传感器。
手机模块224操作和监控驱动电动机110和转向电动机130的行动。
24个超声波换能器24给超声波模块的身体226提供一个输入，指导机器人运动和规避的程序。
最后身体14包含CPU218，除了报警确认单元220也连接软盘控制器，双通道串行I/O 口和一个复位板还有CPU218，输出超声波重置按钮，汽车重置，状态重置，灯塔重置，I/O模块重置，超声波重置。
CPU218也通过RF电路240接收从射频天线65输入的信号。
对各种传感器和传感器领域的高级视图如图4。
24个超声波传感器拥有完整的360°视野。
六个红外传感器28,30,32,34,36,38提供了六个三角形的视野302,304,306,308,310,312并且两个红外线传感器68,334为头部14提供了狭窄的视野。
还有四个微波传感器70,190,330,332提供视图和四个字段318,320,322,324。
这些字段的垂直剖面描绘在图4中。
微波传感器的视野延伸大约一百五十英尺，红外的头部延长约30英尺，并且在内部超声波也要延长大约25英尺。
根据本发明，超声波系统包括了超声波模块图226如图5，还包括Z80处理器等并且还有三个传感器的控制模块330,332,334，每一组驱动8个超声波传感器24。
通信模块226与主机通过串行I/O接口连接如图3.并通过半导体的通讯电缆输入（SOUT）338，和每个传感器的输出（SIN）控制模块336。
虽然每个传感器控制模块控制一组8个传感器24。
实际上分布在所有三个传感器控制模块的内存库控制这些传感器。
因此每个传感器标数为1就与数据库1对应，传感器2是数据库2，传感器3是数据库3.当数据库1被消除时，特定的内存库被激励，指令会通过电缆激励相应传感器。
微处理器的操作是由软件控制模块226控制，串行命令在步骤340处获得数据，图5B。
CPU218中的微处理器226使计数器数据在下一步骤342被清除然后一个输入信号会在步骤344中生成。
这个输入仅提供三个库中的一个，例如库1，增量计数器在步骤346中增加，问题在步骤348中被提问：输出是不是低电平？如果输出不是低电平，这意味着已返回的回声测距数据是可用的。