Modeling And Formation Control Of A Class Of Semi-Biomimetic Robotic Fish

After hundreds of millions of years of natural selection,fish has evolved the ex-traordinary capability of propulsion and maneuverability.Therefore,the study of biomimetic robotic fish will bring great changes into the exploitation of marine re-sources if they can have comparable performance in terms of efficiency,maneuverability and intelligence.At the same time,the research on underwater robotic collaborative control will provide scientific and engineering foundation for underwater exploration and monitoring tasks which are important for the national maritime strategy.This work studies the modeling and dynamics control of the robotic fish,motion control,and formation control of a kind of single-joint semi-bionic robotic fish,which is a con-trollable robot platform for exploring the mechanism of aquatic biological behavior.The study provides theoretic and technological foundation for potential applications of underwater robotic fish.The main research work and contributions can be summarized as follows:(1)From the perspective of system energy,the second kind generalized Lagrange equation is adopted to establish the dynamic model of the biomimetic robotic fish.The translational dynamic equations of motion and the rotational dynamic equations of motion of the fish system are deduced,which provides theoretical foundation for the following research.(2)Research has been done to solve problems in the tracking of biomimetic robotic fish.As they are easily affected by the interferences,the controllability of the dynamic models of the biomimetic robotic fish system is rigorously analyzed.Using feedback linearization design,the nonlinear system is transformed into a linear system by means of nonlinear state feedback or dynamic compensation.The system is proved to be ro-bust to bounded disturbance through Lyapunov method,and the robustness is verified through numerical simulations.(3)As the energy and computational ability of the biomimetic robotic fish sys-tem is limited,we studied the formation control problems.The information consensus communication protocol is proposed,and its convergence is analyzed based on alge-braic graph theory.A consensus based leader-following formation control algorithm is proposed combined with the dynamic model of biomimetic robotic fish,the consensus theory is applied to deal with the formation control of biomimetic robotic fish.We also use simulations to demonstrate its reliability.(4)As the communication load,energy and computational ability of the biomimetic robotic fish are limited in underwater environments,we studied the leader-following formation control of biomimetic robotic fishes based on event-triggered strat-egy.An event triggering function is designed to make the proposed algorithm ap-plicable in realizing control objectives and ensuring control performance with fewer updating times and thus less occupation of channel capacity and less number of com-munications.The expected formation control parameters of the system are obtained by constructing Lyapunov function.Numerical simulation is used to verify the theo-retical analysis of multi robotic fish formation control.