Research On Roll And Yaw Reduction Control Strategy Of Robot Based On Deformation Bionic Fins

As an important sustainable wealth of human society, the ocean resources have become animportant strategy target of all countries. Meanwhile, as a high technology carrier in the fieldof marine resources development and utilization, marine robot has gain more and moreattention. Marine robot can help us better protect the ocean resources of the earth, andefficiently utilize them for human welfare. Due to the actual demand as in engineeringoperations, the research and development of mariner robot operating near surface has becomean important developing direction.When marine robot traveling near surface with low velocity, it will be disturbed by wave,which is different from the situation in deep ocean. As for the disturbance, the marine robotwill have swing motion which affects the attitude balancing, and then the robot’s security andworking performance will be damaged. Since the limits of robot’s low speed, special form andsmall size, a new kind of roll damping device is presented which is base on the theory ofbionics and deformation technology. This device has higher lift generate efficiency andsmaller energy consumption, which is suitable for attitude controlling of marine robotoperating near surface with low speed.In order to study the dynamic characteristics of marine robot navigating near surface, therobot’s6freedom motion model is firstly analyzed in this paper. To simplify the design of thecontrol system and facilitate analysis of the plant, the system equations are linearized about amean operating state, and the marine robot linear equations of motion in state form ispresented. Through the theoretical analysis of the near surface wave disturbance and thesimplification of robot’s outer structure, the wave force model is established by usingMorison’s equation, and the interference range is identified with the numerical simulation.The marine robot roll motion model that is used for roll damping control is established byusing the method of linearization and decoupling. According to the roll damping principal ofmarine robot navigating near surface with low speed，three different control strategies isdeveloped with theory of variable control，adaptive control，feedback linearization andnonlinear tracking control. The specific problems in the roll damping control of marine robotare solved by the proposed control strategies, which is caused by the randomness of wave andnonlinearity of deformation bionic fin’s lift model. The theoretical proof and the results fromsimulation experiments are presented to demonstrate the stability and validity of the controllaw proposed. Further, the marine robot motion model in horizontal plane with coupling of roll, yaw andsway is presented, and the effect from system’s uncertainty which is caused by hydrodynamiccoefficients and disturbance is considered. According to the principle of rudder/fin joinedcontrol, an adaptive controller for course keeping and roll damping is designed by using thetheory of terminal sliding mode control. Genetic algorithm is carried out to optimize thecontroller parameters based on the parameterization formula, aiming at getting comprehensiveoptimal of roll reduction and energy consumption. Through theoretical analysis and numericalsimulation, the presented controller is proved to be stable and effective, meanwhile, theenergy consumption is reduced.