机电一体化专业英语

机电一体化专业英语主编宋主民Mechatronics1.1 Introduction1.2 Mechatronics products1.3 Mechatronics production systemMechatronics is the abbreviated form of the word s of mechanical and electronics. It was created by Japanese but you cannot find it in dictionary. Mec hatronics is also the combination of the science o f mechanical engineering and electronics. Mechat ronics was defined by EEC ( the European Econom ic Community) as “the optimum cooperative com bination of precise mechanical engineering, electr onic control and system technique considered in designing products and manufacturing system”.A typical mechatronics product such as numerical controlled (NC) machine tool or industrial robot is composed of machinery and microprocessor ba sed electronic circuit including signal sampling, da ta acquisition and processing, and computer cont rol. Compared to traditional mechanical product, mechatronics product has the advantages of high er precision, higher productivity, higher reliability and lower consumption of energy, material and la bour.1.2.1 Constitution of mechatronics products 1.2.2 Common and critical technologies in developing mechatronics product1.Mechanical system2.Transducer3.Measuring instrument4.Data acquisition5.Signal analysisputer controlin developing mechatronics product1.Transducer and measuring techniques2.Data acquisition3.Signal analysis/data processing4.Servo driving system5.Precise mechanical technique6.Systematic techniqueMechatronics production system In reviewing the history of developing automatic manufacturing system（In fact it is mechatronics manufacturing system）in the past century, schol ars divide it into five stages as shown in Fig.1.41.3.2 Facilities automation stage 1.3.3 Flexible automation stage 1.3.4 Data automation stage 1.3.5 Decision automation stageIn the 30’s of the 20th century it was represented by Ford productive mode which adopted the prod uctive manners of interchangeability, flow proces s and using specific automatic machine to realize rigid automation in large scale production.It was represented by NC, CNC, DNC and industria l robot in 1940’s to 1960’s. Since soft program me dium of the workpiece machined is used in NC m achine tool, there is no longer the contradiction b etween the universality and automaticity of mach ine tools. This leads to realizing automatic manuf acturing in small batch even one type one piece production, which motivates renewing products a nd makes our life colourful.(1)FMS is composed of a group of NC machine tools, since a workpiece usually needs more than one operation to machine it, but the working time for each operation is different.(2)A material handling system (MHS) is implemented in FMS to greatly decrease the idle time in manufacturing including parts/tools presetting, transport and mounting etc.(3)FMS is featured by its flexibility, which enablesthe system to adapt any change of the manufa cturing system;In 1980’s to 1990’s it was represented by CIMS (c omputer integrated manufacturing system). CIMS is aimed at building a data integrated system sup ported by computer network and database techni ques, in which each division of the enterprise incl uding production planning, product design, manu facturing, management, quality control, sells and purchase etc. can share the data with any other, s o that the correct data of each division can be tra nsmitted to correct place/man at correct time. Th is is greatly helpful for the decider of enterprise t o make correct decision.From 1990’s, manufacturing entered decision aut omation stage which is the combination of manuf acturing and computer science in expert system a nd artificial intelligence. In decision automation s ystem, knowledge of various field experts includi ng chief engineer, engineer of design, manufactur ing and management is stored in a knowledge ba se.2.1 Introduction2.2 Performances and evaluation index of transdu cer2.3 Transducer of measuring displacemente critical techniques and basic links of a mechatro nics product. A transducer is generally composed of sensitive element, transferring element and ba sic transfer circuit as shown in Fig.2.1.of transducer1.Measuring scope and range2.Sensitivity3.Linearity4.Repeatability5.Stability6.Accuracy7.Dynamic performance2.3.1 Resistance-type displacement transducer2.3.2 Resistance strain guage-type dis placement transducer2.3.3 Capacitance-type displacement tr ansducer2.3.4 Inductance-type displacement transducer2.3.5 Turbulence-type displacement transducer2.3.6 Piezoelectrics-type displacement transducer2.3.7 Magnetic grillage-type displacement transducer2.3.8 Optical grillage-type (or simply grillage) displacement transducer2.3.9 Inductosyn2.3.10 Pulse generator2.3.11 Resolver2.3.12 Laser-type displacement transducer-type displacement transducer〓Resistance strain guage type displacement transducer-type displacement transducer-type displacement transducer-type displacementtransducerFig.2.10 The structure of measuring head of inductance micro dimensional measurer1—Probe 2, 9—Cap 3—Cover 4—Shielding cover 5—Secondary coil 6—Primary coil 7—Frame 8—Magnetic iron 10—PlugFig.2.11 Turbulence type displacement transducer 1—Coil 2—Measured conductive object 3—FramePiezoelectrics typedisplacement transducerWhat this kind of transducer to do is first transfer ring displacement into force variation which then is transferred into electric signal in terms of piezo electric effect for measuring displace-ment.-type displacement transducerFig.2.12Magnetic grillage-type displacement transducera) Signal picked by dynamic magnetic head b) Magnetic head structure1—Magnetic head2—Magnetic rule3—Wave form-type (or simply grillage) displacement transducer •1. Principium of linear grillage2. Circular grillageFig.2.13 Generation of Mole fringeFig.2.14 Circular grillagesFig.2.15 Coils of inductosyna) Line-type b) Rotation-type 1—Fixed rule 2—Slide rule 3—Rotator 4—StatorFig.2.16 Composition of incremental pulse generatorFig.2.17 Coding mask of absolute encoderFig.2.18 Mutual inductance of resolver-type displacementtransducerFig.2.19 Constitution of single frequency laser interferometer system 1—Inspected carved rule 2—Table 3—Fixed prism 4—Movable prism 5—Phase plate 6, 10, 11, 12—Reflector 7—Dichroic mirror 8—Optical electric element 9—Object mirror13—Semi circle light banister 14—Parallel light tube 15—Stabilized frequency circuit16—High voltage source 17—Helium neon laser generator•There exist many kinds of speed transducer used to measure shaft speed including tachometer generator, magnetic-electric tachometer, optical-electric tachometer and laser Dopplar tachometer etc.-C tachometer generatorFig.2.20 D C magneto tachometer generator-type speedtransducerFig.2.21 Measuring speed with incremental encoder-type speed transducerFig.2.22 Schematic of Hull element-type speed transducer 1—Magnetic steel 2—Hull element 3—Object measuredFig.2.23〓Turbulence type speed transducer 1—Eddy current displacement transducer〓2—Gear shape plate•Acceleration transducer is used to measure vibration signal. When the object vibrates about an equilibrious position, the velocity, initial force, displacement and acceleration of the object are all the vibration signal which implies the parameters of the vibration system such as natural frequency and damping ratio etc.Piezoelectrics-type acceleration transducerFig.2.24 Piezoelectric type accelerator1—Mass (initial element) 2—Piezoelectric element3—Base 4—Output link 5—Sensitive direction。