| Inertial piezoelectric actuators have much characteristic such as compact configuration,good response characteristic,non-electromagnetism interfere,convenient control and so on,they are often applied on high resolution,large displacement occasion and accepted widelyattention。Specially in recent years as the performance of piezoelectric element beingimproved, its application is gradually enlarging.Based by controlling the orderly changes of the PZT moving mechanism and frictionbetween supporting faces in mechanical way, a novel kind of inertial piezoelectric actuator isproposed. The moving principle is analyzed, the structure of new inertial piezoelectric actuatoris designed and manufactured, it can realize single dimension reciprocating and rotary motion,and the main content is as follows1.IntroductionThrough the general introduction to main application field,main types with advantages anddisadvantages ,current actuation material , the paper draw a conclusion that PZT has a greatadvantage in precision actuation field . Also, the chapter gives the analysis of the practical structure and the existing problems ofpiezoelectric precision actuator.2. Basic theory on piezoelectric driving.The chapter discusses piezoelectric effect and converse piezoelectric effect.Discuss the basic principle of piezoelectric ceramic and kinds of piezoelectric actuator designthe driver of precise actuator. It supplied theoretical dependence to the selection ofpiezoelectric multilayer actuator and the design of precise actuator.The factors which influence Piezoelectric performance include electromechanically coupledcoefficients K ,mechanical quality factor Q_m,relative dielectric constant ε,elastic constants,piezoelectric constant d and performance parameters ,etc.Piezoelectric material is a kind of elastic solids and its electric characterization can bedescribed by electric field intensity E and electric displacement D. for a dielectric free fromexternal force in electric field, the relation between electric field intensity and electricdisplacement is:D=εEPiezoelectric stack is a kind of rigid ceramics. For its heavy output force and easy controllable,piezoelectric stack is especially suitable for precision driving.3. Inertial actuator principle and structure designBased by controlling the orderly changes of the PZT moving mechanism and friction betweensupporting faces in mechanical way, a novel kind of research project of inertial piezoelectricactuator is proposed.The whole structure of new single diminution and rotary inertial piezoelectric actuator isdesigned, and analyzed the performance of piezoelectric ceramic, the characteristics ofVoltage-displacement, Creep, Hysteresis Curves are tested circling the prestressed force toPMA, as well as the Impedance Characteristics and Frequency response.Established dynamics model of system, carried through kinematics simulation by making useof MATLAB software。4. Research on control circuit of inertial Actuator.Displacement resolution and response frequency of driving powers piezoelectric actuatorsare mainly determined by dynamic performance of driving powers。As for external driving powers, piezoelectric ceramic is equivalent with capacitive load,capacitance C is relatively large, circuit RC made by output resistance R and capacitance Cinfluence dynamic performance of driving powers。The principle and limitations of existingdriving powers for piezoelectric ceramic are analyzed, then a newly developing driving poweris presented in detail。5. Test and Research on inertial Actuator.Based driving principle and simulation analysis result of newly inertial actuator, tow kind ofinertial actuators, linear and rotary actuators, are designed and manufactured, theircorrelative performance are tested,The main contest of test include the linear step size,loadability ,rapid and the rotation step size,rapid and load ability of the actuator。The result is:the linear actuator can provide stable stepping movement, the maximum speed of 1mm/s, highresolution of 50nm, maximum loading capacity of 1000g. rotary actuator can provide themaximum rotary speed of 0.26 rad ? s?1,high resolution of 20 μr ad and large movingrange of 360°.6 ConclusionThe chapter gives the main conclusion obtained in this paper and the prospect for nextresearch.
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