Motion Control for a Stingray-Like Robotic Fish with Undulating Pectoral Fins

Abstract

Stingrays have expanded and highly flexible pectoral fins that extend over the entire length of their body. Locomotion is controlled by modulations of the undulating fin surface which produce steady swimming, acceleration, or complex maneuvers. In this paper, a robotic fish inspired by stingray was presented. Structure of the biomimetic prototype and layout of the control system were illustrated. In order to mimic the undulations, parameters of the biomimetic pectoral fin need to be accurately controlled including frequency, amplitude, wavelength, and undulatory mode. Several control strategies were proposed to realize different kinds of locomotion. Lastly, swimming experiments were carried out in the water tank according to the control methods. Experiment results demonstrate the viability of our methods.