Gait Planning for Steady Swimming Control of Biomimetic Fish Robots

Abstract

This paper is dedicated to the implementation of biological fish swimming motion onto biomimetic fish robots. By learning from different species of fish, the mechanism design and the motor control of swimming machines could be shaped in different forms. In general, they can be grouped into two major forms, from an engineering viewpoint: serial open-chain design and parallel mechanism design. The gait planning on both forms is then performed based on the well-established theory of fish swimming. By using the associated kinematics equations, the generic solution of the gait planning for multi-link fish robots in the two respective forms of mechanisms is derived. The solution is taken as the gait control input for the swimming testing of a six-link body and/or caudal fin fish prototype and an eight-link media and/or paired fin fish prototype. The experiments show that smooth steady swimming and forward/backward swimming are achievable by making use of the gait planning and control.