Study on a new type of miniature piezo walking robot

Abstract

Abstract The development of a small-scale piezoelectric-driven walking robot is presented in this paper. Eight pieces of piezoelectric bimorph actuators are employed in the proposed design to achieve a direct drive. The displacement amplification mechanism of the robot is not required to minimize the weight and complexity. This robot is composed of four inner legs and four outer legs with a slop to the ground. Two square wave signals with a phase difference of 180° are used to realize bidirectional motion. First, the constitutive equation of piezoelectric bimorph with elastic support layer under external voltage and force is deduced. Then, the robot gait cycle is described, and the velocity expression of the robot is established using the kinematic analysis to predict the robot’s motion. Afterward, a prototype is fabricated on the basis of the proposed design. Finally, an experimental test is conducted for characterizing the walking robot. The design methodology can be applied to the development of the other piezoelectric robot for bidirectional motion.