| Inertia piezoelectric actuators have much characteristic such as the compact configuration, good response characteristics, and no-electromagnetic interference, convenient control. It's often applied to the occasions of high-resolution and large working range.Thus inertia piezoelectric precise Actuators have become an important branch in in the precise actuation field.A 3-DOF inertia actuator driven by piezoelectric stack is put forward and developed in this paper. The impact force generates when the symmetric voltage (such as squre wave)is applied. By changing friction (or moment) between the driving mechanism and the contact surface through the way of changing the press between them, and cooperate with the inertial driving force (or moment) to achieve three degrees of freedom (x, y,θ) precision actuator.During the developing progress, some approaches are adopted, for example, theoretical derivation, simulation and experimental tests, etc.1. IntroductionDriven by piezoelectric materials has great advantages over other kinds of driving ways, such as small volume, high movement precision, rapid response, low voltage, easy to control. Piezoelectric actuators are divided into there kinds. The inertial drive actuator plays an important role in this field as a result of its particular characteristic. Introduce the research background of Precision actuator. Three actuation types of PZT actuators are introduced and compared. At last, it discusses the current the main application fields of precision actuation.2. Introduction performance of the piezoelectric stack and the analysis to the inertial impact characteristic of piezoelectric stackIn order to better understand the characteristics of piezoelectric stack, the performance parameters, basic features are discussed to know the piezoelectric drive better before actuator is designed. So found a solid academic foundation for designing the precision actuator. The principle of piezoelectric driving utilizes converse piezoelectric effect. The piezoelectric stack AE0505D16 relevant parameters are mainly mechanical quality factor Qm, electromechanical coupling coefficient K, relative dielectric constantε, elastic constants S, piezoelectric constants d ,constant frequency N1; hysteresis characteristics, capacitance characteristics, stiffness characteristics KT. etc. Based on the knowledge of the piezoelectricity and the dynamics, the Simulink simulation model is established. The simulation and experimental results provide theoretical foundation to master the dynamic characteristics of piezoelectric stack and to improve the performance.3. The theoretical and simulation analysis on the 3-DOF inertial actuatorA 3-DOF inertia actuator driven by piezoelectric stack is put forward and developed. The impact force generates when the symmetric voltage (such as squre wave) is applied. By changing friction (or moment) between the driving mechanism and the contact surface through the way of changing the press between them, and cooperate with the inertial driving force (or moment) to achieve three degrees of freedom (x, y,θ) precision actuator.The dynamic model is established, Furthermore, the simulation model of the actuator based on the Karnopp frictional model is also established.Through theoretical and simulation analysis to the dynamic characteristics of the actuator, the relationship between the output ability and the input parameters are obtained. The input parameters include friction coefficient, voltage, load, bottom press and so on. The conclusions from that are as follows: (a)At the same value of static coefficient, the rotation and translation step increases as the dynamic friction coefficient decreases.Therefore the more difference of static and dynamic coefficient of friction ,the larger drive capability of actuator ;(b)With the increasing of the drive capability, translation / rotation Step decreases; (c)With the the increasing of the pressure between the actuator and the support, translation / rotation step increases. Therefore the more heavy of the quality block and the higher voltage of piezoelectric stack which changing pressure between the actuator and the support, the larger drive capability of actuator.The results of the analysis provides a theoretical basis for the design of the actuator.4. The structural design and experimental study on the 3-DOF inertial actuator.Based on driving principle and simulation analysis result of simulation , the 3-DOF inertial actuator is designed and manufactured, the correlative performance are tested,The main contest of test include the translation / rotation step with the friction coefficient, load, bottom press. And also test the actuator translation and rotation speed, the rotation interference error of the translation, translation interference error of the rotation. Discuss the reason of the interferential error. To reduce the multi-degree of freedom interference error, a conical surface regulator is put forward. The test results indicate that: drive capacity is greater than 1000 g, the resolution of translation 0.5 m, rotary interference error is less than 15%, the working range is greater than 10 mm; rotatation resolution of rotation is 12 rad, translational interference error is less than 30%, the working range is greater than 360o; with the conical surface regulator conical surface, the translation of the resolution is 0.4 m, rotary interference error is less than 20%, rotation resolution of 11 rad, translational interference error is less than 20%.5. Research on control system of interference error of the actuator based on LabVIEWDiscuss the closed-loop system's hardware components and testing principles, elaborate the RS232 serial port for data acquisition parameters in the chapter. In order to improve performance of the actuator, a set of feedback control system has been developed, i.e. virtual apparatus based on LabVIEW. By the virtual apparatus, the input signal of interference error is processed to convert the output signal of control voltage. So the data acquisition and the algorithm have been improved and the control software has also been developed. Through translation / rotation interference control system interference error is greatly reduced.6. Conclusions and OutlookMakes a conclusion to the whole paper, and gives some suggestion for future development.
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