The research on the nonlinear control of carangiform biomimetic robotic fish

Carangiform biomimetic robotic fish are underactuated mechanical systems whose governing equations are highly nonlinear. Based on the quasi-steady flow model of a three-link biomimetic robotic fish of Caltech, we have the model form of a control-affine nonlinear system with drift. Then we make use of geometric tools to research control methods of forward gaits and turning gaits. Through analyzing system simulation response, we can see that carangiform biomimetic robotic fish accomplish forward and turning gaits preferably. Simulations results are shown that nonlinear control methods are effective to improve forward propel speed and turning performance, which have laid foundations for future researches.