Development of a miniature piezoelectric robot combining three unconventional inertial impact modes

Abstract

A novel miniature piezoelectric robot (MPR) was designed and proposed in this work, in which a unique structural feature is that the robot base is only obtained through a single cuboid block, having good simplicity and compactness. Besides, unlike the slow-fast periodic horizontal deformation of the inertial unit in traditional inertial impact mode, three unconventional (diagonal, jumping, resonant) inertial impact modes (DIIM, JIIM, and RIIM) based on the unique structure of the robot were proposed to achieve the performance improvement in both resolution, single step value, and motion speed. The three working principles were analyzed, and the main geometric parameters were determined by the cooperation of the established model and the finite element method. Then, a robot prototype with a size of 20 mm × 12 mm × 9 mm and a weight of 4.7 g was manufactured, and the motion performance was tested, in which the robot was powered by an external power supply by wires. The results showed that the robot could achieve both high resolution, large single step, and high motion speed successfully by cooperating the three inertial impact modes, including a highest resolution of 0.5 µm under DIIM, a maximum single step of 63.1 µm under JIIM, and a fastest speed of 24.8 mm/s under RIIM. The coordination of these performance could well expand the application scope of MPRs.