Containment Control For Multiple Networked Robots Based On Event-triggered Mechanism

Compared with single robot with complex structure and function,a multi-robot system composed of multiple robots with simple structure has many advantages such as lower cost,greater redundancy,better robustness and higher flexibility.Therefore,a multi-robot system has better performance and wider application prospects in the complex,unknown,dangerous environment and has gradually become the main trend of the development of robot technology.The problem of containing control with multiple leaders as a very practical problem of multirobot system has become the hot topic of multi-robot system research.At the same time,multirobot systems based on event-trigger mechanism control strategies can reduce the frequency of control updates,which gives these multi-robot systems the advantage of low resource consumption.In this paper,containment control for multiple networked robots based on event-triggered mechanism is studied.Firstly,a multi-robot system kinematics model that can reflect the position and attitude of followers is established.Secondly,depending on this model,a containment control protocol is designed based on all levels of error surface and event-triggered mechanism with fixed threshold is designed to reduce the frequency of control updates.Then,to improve the event-triggered mechanism with fixed threshold,the event triggered mechanism with relative threshold is designed which can change threshold with the size of the control input,and the steady-state error of multi-robot system is reduced.Finally,considering the influence of external disturbance on multi-robot system,the extended state observer is designed to estimate the external disturbance and compensate the influence of external disturbance in the containment control protocol,which improves the anti-disturbance ability of multi-robot system.In the design of each control protocol,according to Lyapunov stability theory,the stability of the design control protocol is proved,and the proposed control protocol can ensure that all followers can converge into the geometric convex hull composed of leaders.All of containment control protocols based on event-triggered mechanisms are proved that Zeno phenomenon will not occur.The proposed control protocol is simulated by MATLAB/SIMULINK software,and the results verify the validity and superiority of the proposed containing control protocol.