Study On Asymmetrical And Frictional Piezoelectric Inertial Rotary Actuators

Piezoelectric inertial rotary actuators, which serves as a precise positioning device based on piezoelectric bimorph, are universally utilized in microswitch, scanisterm, fast steering mirror, microrobot due to the merits of simplified structures, large watt density, high accuracy, as well as considerable working efficiency. Although several research progress has received on the types of asymmetrical and frictional piezoelectric inertial rotary actuators, respectively, the kinetic characteristic comparison between these two actuators are seldom reported ever since. Consequently, this dissertation concentrates on this research direction combining National Natural Science Foundation. Based on the driving unit of piezoelectric vibrators and the principle of inertial impaction, the designed and fabricated prototype together with the built test platform are integrated to analyze the motion performance of those two kinds of piezoelectric inertial rotary actuators by means of experiment. Specific researches are as follows:1. Focus on piezoelectric inertial rotary actuators, regarding the piezoelectric bimorph vibrators as the driving unit, the material, form, support formulas, mode of connection, and the dimension are determined. In addition, after ascertaining the asymmetrical structures, the motion process as well as the mechanical status are analyzed. Further, the influences on the tip amplitude and the running torque of piezoelectric bimorph vibrators affected by clamping difference and driving voltage are delineated by MATLAB software. Besides, the driving mechanism of frictional piezoelectric rotary actuators and the specific vibrators equipped with asymmetrical clamping structures and changeable angles are also analyzed.2. Propose a piezoelectric inertial rotary actuator drove by piezoelectric bimorph, modeling, design the structure of actuator, analysis of work principle of the actuator, based on asymmetric inertial shock. Designed the asymmetrical piezoelectric inertial rotary actuator consists of rotary drive unit and variable friction equipment. The working principle of the actuator is analyzed in symmetrical square wave. Propose an frictional piezoelectric inertial rotary actuator by changing the positive pressure. The frictional piezoelectric inertial rotary actuator is modeled and analyzed of work principle, influenced on friction.3. Developed on an inertial piezoelectric rotary actuator, which can realize the adjustable clamp differential and the change of the asymmetrical structure; and it can realize adjustable friction by adjusting the angle of piezoelectric bimorph and the horizontal plane. The preliminary test shows that the linear degree and the repeatability of the rotation step of the asymmetric piezoelectric rotary actuator is better than the variable friction type; the friction adjusting device significantly improves the friction force, which is helpful to improve the stability of the rotating step of the variable friction type inertial piezoelectric actuator; controllable friction device can reduce the drive rotary step.