Development of a cross-scale 2-DOF piezoelectric rotary platform based on active friction switching

In order to overcome the typical cross-scale motion contradiction between the large motion range (radian scale) and high displacement resolution (microradian scale) in single actuation device, we proposed a novel two degrees of freedom (2-DOF) piezoelectric rotary platform (PERP) to implement cross-scale rotary motions based on active friction switching. A longitudinal-bending-bending (LBB) piezoelectric actuator (PEA) was developed to realize 2D lateral bending motions and 1D longitudinal motion. The former was used to drive rotor, while the latter was employed to implement friction switching. The principles of the PERP and the switching mechanism of the working modes were illustrated systematically. The finite element method (FEM) was utilized to simulate the motions of the PEA, and a series of experimental results successfully verified the principles and the theoretical analyses. The 2-DOF cross-scale rotary motions were successfully realized, and the PERP can achieve large motion range of 2 pi rad, maximum rotary velocity of 817.88 mrad/s, high resolution of 23.03 grad and low coupling motion of 4.91%. The proposed friction switching method held benefits to improve flexibility and stable frequency range (more than 10 times) of dynamic scanning motion. The developed PERP could be used to drive optical mirrors with merits of both large motion range and high resolution for multiple target tasks.

Automated summary

This study proposes a novel two degrees of freedom piezoelectric rotary platform that achieves cross-scale rotary motions based on active friction switching. The platform has a large motion range, high resolution, and low coupling motion, making it suitable for driving optical mirrors and other multiple target tasks.