Research On Synchronized Terminal Sliding Mode Control Of Multiple Mobile Robots

Due to their high degree of autonomy,mobile robots are widely used in field operations,medical,military and service industries,as well as in some toxic or high temperature environments.It is difficult for a single robot to perform some complex tasks that need to be processed efficiently,and multiple mobile robots can accomplish tasks that cannot be accomplished by a single robot through cooperative formation.Because multi-mobile robot systems have problems like strong nonlinearity and system uncertainty,and are vulnerable to external environment,it is especially necessary to study the formation structure and control algorithm of multi-mobile robots.In this paper,the multi-mobile robot system is taken as the research object,combined with cross-coupling synchronous control,the terminal sliding mode control of the kinematics and dynamics model of mobile robot is studied.According to the transient kinematics model of mobile robot,a cascade control system is designed to avoid the interference caused by multi-input coupling of traditional kinematics model.Considering the system uncertainty and the interference of the external environment,a terminal sliding mode synchronous controller is designed by using the strong robustness and anti-interference characteristics of the terminal sliding mode,which realizes the finite time convergence of the system error.Robust control and adaptive law are introduced in the controller to offset the influence of lumped uncertainty and real-time adjustment of controller gain to improve control performance.The stability of the control system is verified by the Lyapnov method,simulations and an experiment.According to the second-order dynamic model of the mobile robot,the state of the pilot robot is not known.The finite-time distributed state observer is designed to realize the state observation of the pilot robot.Considering the interference of the external environment,a non-singular terminal sliding mode synchronous controller is designed to realize position synchronization and speed synchronization.Robust control is introduced into the controller to counteract the effects of external interference.The stability of the control system is verified by the Lyapnov method and simulation.Based on the centralized controller design of the two models,according to the principle of distributed control structure,a distributed synchronous terminal sliding mode controller is designed for the kinematics and dynamics models.A disturbance observer is designed to counteract the effects of interference for the transient kinematics model.Aiming at the interference problem of second-order dynamic systems,an adaptive control rate based on the upper bound of interference is designed.The Lyapnov method and simulation results demonstrate the stability of two distributed control systems.