Achieving high consistency in forward and reverse motions of stick-slip piezoelectric actuator by a symmetrical structure and optimized installation method

Although the stick-slip piezoelectric actuator has been extensively developed, its consistency in forward and reverse motions is still poor under the same driving voltage and frequency. To improve the consistency in forward and reverse motion, extremely precise adjustment of actuators is necessary. For achieving high consistency in forward and reverse motions with low difficulty in assembly and adjustment, a stick-slip piezoelectric actuator with the symmetric mechanism and optimized installation method was developed in this study. By means of the pseudo-rigid body method (PRBM), matrix-based compliance modeling (MCM) method and the finite element method (FEM), theoretical calculation and analysis of the designed symmetric flexure hinge mechanism (SFHM) were carried out firstly. Then, the effects of installation methods on the forward and reverse motion consistency were investigated by experiments, and accordingly, an optimized installation method was determined. With this method, output performances of the actuator were tested under various voltages, frequencies and external loads, and the consistency in forward and reverse motions were further compared and analyzed. The experimental results indicated that good consistency in forward and reverse motions had been successfully achieved by the symmetric mechanism and optimized installation method, and the ratio of difference λ was only 6.80% which showed the actuator had an extremely competitiveness. High bidirectional motion consistency will reduce the control difficulty of the actuator, which is beneficial to its application in the fields of precision instruments, aerospace and material mechanical performance testing.