Inchworm type microrobot using friction force control mechanisms

Abstract

We studied inchworm type microrobots using piezoelectric elements. When the microrobot moves, friction between the microrobot and an operation surface disturbs the displacement of the microrobot. We propose the inchworm type microrobot which can control the friction force. The friction force is controlled by the use of squeeze film effect. The microrobot is composed of three friction force control mechanisms, two horizontal piezoelectric elements, and leaf springs. The friction force control mechanism is composed of a metal plate, a weight, and a stacked type piezoelectric element. When a vertical piezoelectric element vibrates vertically, the squeeze film effect occurs and the friction force control mechanism levitates. The leaf springs are used as vibration isolators. The friction force control mechanism levitating in air moves by the push and pull of the horizontal piezoelectric elements. In this study, first, the height of a bottom plate of the levitation mechanism is measured. Then we changed the control frequency and waveforms, and measured the velocity of the microrobot.