Hardware in the Loop Simulation and Analysis of a Model of Fish Robotic System

Abstract

In the present study, an adaptive sliding mode control method was employed to control a fish robotic system using hardware in the loop methodology. Up to now, few researches have focused on autonomous control of fish robot in dynamic environments which may be the result of difficulties in modeling of hydrodynamic effects on fish robot. Therefore, following the introduction of the nonlinear model for the robot, elongated body theory, suggested by Lighthill, was used to analyze fish movements. Then, kinematics control to track desired trajectories was designed for under-actuated model of robot. Adaptive sliding mode controller, capable of adapting according to changes and uncertainties, was designed and implemented. Using a fabricated stand, experimental tests were performed using hardware in the loop simulation. Computer simulations accompanied by experimental results verify that the presented adaptive controller has two main advantages: first, they make a robot versatile and capable of moving in unknown environments because of system robustness under changes and uncertainties of parameters. Second, they leave out the need for expensive and time consuming experiments to recognize system model and reduce operations for final tuning of controller.