Modeling and experiments of a nano-positioning and high frequency scanning piezoelectric platform based on function module actuator

A piezoelectric platform using function module actuator is presented to achieve nano-positioning and high frequency scanning in large working range. A function module actuator is designed to produce a pair of orthogonal bending deformations and a longitudinal deformation through partition exciting. The bending deformations are used to actuate the planar motion, while the longitudinal deformation is utilized to dynamically adjust the driving force and broaden the scanning frequency. The dynamic model of the platform system is developed. The open-loop performances of a prototype are first tested: a scan frequency of 308 Hz in a scanning range of 3.368 µm×3.396 µm is measured in direct actuation mode, and the displacement resolution is measured to be 16 nm; maximum speed is measured to be 3.38 mm s −1 in the inertial actuation mode. Furthermore, the closed-loop experiments are carried out and a switching strategy is proposed to obtain the switching of the inertial and direct actuation modes automatically; the platform achieves the scanning with frequency of 300 Hz at the set position.