| The rotated actuator which was driven by piezoelectric inertial concussion using asymmetrical gripper are developed in this thesis, with the support of national natural science sustentation fund program"The Theory and Experimental Study of New Style Micro Inertial Actuator Driven by Piezoelectric Travel Mechanism". Using piezoelectric multilayered actuator (PMA) to replace traditional piezoelectric stack as the drive element, using its characteristics of high power destiny, large output force, fast response and high resolution; getting the forward backward driving moment difference through inputting symmetry signal, not using traditional saw-tooth waveform electrical signal; realize the output of rotated precision displacement, using square wave signal to produce inertial impact force; developing the actuator through deducing in theory, finite element simulation and experimental measurement.The paper consists of six chapters, given as follows:1. IntroductionNowadays, the piezoelectric control valves, such as the electro hydraulic ON/OFF valves, electro hydraulic proportional valves and electro hydraulic servo valves, are mainly research areas for the domestic and foreign researchers. The application of ON/OFF valves mainly concentrates on MEMS active valves and fuel injection control valves, while piezoelectric electro hydraulic proportional valves and piezoelectric electro hydraulic servo valves are mainly used in electro hydraulic proportional system and electro hydraulic servo system. Piezoelectric electro hydraulic servo valves are the hot research areas because of they have the characteristics of high frequency, high resolution, compact structure and highantipollution ability. The actual inertial actuator is commonly driven by adopting piezoelectric stack, inputting saw-tooth waveform. The high bandwidth valves have small flow rates, while the large flow rates valves have low bandwidth. Such cases limits the application occasions. Thereby this paper put forward a kind rotated actuator, which is driven through inputting symmetry wave, using piezoelectric bimorph vibrator based on the principle of asymmetry gripper.2.The basic theory of piezoelectric drive and principle analysis of asymmetry gripper inertial driveThe piezoelectric effect and converse piezoelectric effect are the fundamental of piezoelectric drive. The piezoelectric ceramic is one of piezoelectric material which in common use. The factors influence performance include dielectric constantε,elastic constant s,piezoelectric constant d,electromechanically coupled coefficients K,mechanical quality factor Qm, etc. Piezoelectric material is an elastomer, it has four piezoelectric equations with different independent variable at various boundary conditions.In general, piezoelectric material fixed with some elasticity material to form the vibrating body, and it is called the complex piezoelectric vibrator. The Piezoelectric bimorph vibrator is made of piezoelectric ceramic part and metal part. Piezoelectric bimorph adopt the LE mode of piezoelectric oscillator and is a piezoelectric component with large deformation output, easy-to-control, higher response rapid which suits for the inertial impact precise drive. The paper introduces the structural style and the performance parameter of piezoelectric bimorph, its performance parameter is the main basis to design the piezoelectric vibrator.Present the new piezoelectric inertial drive principle in the case of directional motion, according to the difference of forward backward inertial driving force Using piezoelectric bimorph vibrator. Analyze the motion dynamic performance, ascertain actuator's four motion state through calculating Mq1, Mq2 and Mf, and the conclusion is: make Mq2≤Mf |
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