Experimental Study on Oscillating Wing for Propulsor with Bending Mechanism Modeled on Caudal Muscle-Skeletal Structure of Tuna

Abstract

The purpose of our study is to investigate the effect of the caudal fin behavior resulting from the caudal muscle-skeletal structure of tuna on the propulsive force. A propulsion system by tuna-like fin stroke using two air rubber artificial muscles and a multi-joint bending mechanism (a tuna-like bending mechanism) modeled on the antagonism muscles and the caudal skeletal structure of tuna was developed. In order to realize instructed oscillation of a wing, a method of continuous path follow-up control of a wing in water was discussed in regard to the control of the internal pressure of the artificial muscles. It was found that the optimum control method for the tuna-like bending mechanism was the pressure control of the artificial muscles with both feedforward and pressure feedback compensations. The propulsion performance on a deformable wing using the propulsion system was discussed.