Structural design and analysis of 3-DOF bionic eye based on spherical ultrasonic motor

Abstract

Vision system is crucial for autonomous robots. In order to realize some visual performances by complicated eye movements, like tracking target, image stabilization and vestibulo-ocular reflex, we present the mechanism and simulation of a robot bionic eye based on spherical ultrasonic motor (SUSM) with three rotational degrees of freedom (3-DOF). SUSM is a compact mechanism occupying little space but good responsiveness, high positioning accuracy, high torque at low speed and strong magnetic field compatibility. So based on SUSM, the bionic eye is fit to solve the problem of vision instability during robots' working. The bionic eye is constructed of three annular stators adhered with several piezoelectric elements and a spherical rotor as a camera actuator. The rotor is driven by frictional forces from the three stators accompanying with same preload generated by the deformations of specialized coil springs. Through simulation by a virtual prototype to analyze the rotational speed, torque and responsiveness, our mechanical design is verified to be reasonable and effective preliminary. © Springer-Verlag Berlin Heidelberg 2012.