Research On Formation Control Algorithm Of Multiple Mobile Robots

Multiple mobile robots are widely used to assist military operations,remote operations,automatic chemical plants and agricultural labor.With the continuous expansion of the application scope of the mobile robot,the performance of robot cooperation is required to be higher and higher.In practical application,multiple mobile robots are easily affected by the external environment,resulting in low control accuracy,poor adaptive ability,slow formation adjustment and other problems.Aiming at the above problems,this paper studies the formation control of multiple mobile robots.The main research contents are as follows:Firstly,aiming at the problems of low efficiency and a large amount of calculation in target point assignment,a target point assignment algorithm based on screening in a static obstacle environment is proposed.the path set of each robot participating in the formation of each target point is calculated,and multiple target point allocation prediction matrices are formed by screening.The real-time position coordinate equations of the robot are established according to the current screening prediction matrix,and the equations are solved.By judging whether the equations have solutions to determine whether the current target point allocation strategy exists collision,until the shortest path synthesis and the least time-consuming optimal solution of target point allocation is obtained.Experimental results show that the proposed algorithm is not only effective but also efficient.Secondly,the formation keeping strategy is studied based on the expected formation.In order to achieve stable formation,a three closed-loop sliding mode formation control algorithm is designed.linear velocity control law and angular velocity control law are designed respectively to form three feedback links to maintain the stability of the system.Compared with other sliding mode formation control algorithms,it is proved that the proposed control algorithm not only improves the adaptability and stability,but also greatly improves the control accuracy.Then,in order to smooth the tracking track of robots,a formation control algorithm of multi mobile robots based on fuzzy sliding mode control theory is proposed by introducing fuzzy logic theory into the three closed-loop sliding mode formation control algorithm.By designing fuzzy rules,the switching gain is smoothed,compared with other fuzzy sliding mode formation control methods,the experimental results show that the designed controller can smooth the tracking trajectory of robots effectively and has a higher antiinterference ability.Finally,in order to further improve the control accuracy,a prescribed performance formation control algorithm based on fuzzy sliding mode control theory is proposed.By establishing the motion dynamics model of the mobile robot,solving the differential equation of relative position error,a fuzzy sliding mode controller based on hyperbolic tangent obstacle function and prescribed performance function is designed to realize high-precision and stable formation of multiple robots in arbitrary formation.The results of MATLAB simulation and comparative experiments show that the prescribed performance fuzzy sliding mode control algorithm can not only realize the formation of multiple robots in arbitrary formation,but also ensure the transient and steady-state performance of robot formation.Compared with the existing control methods,the prescribed performance formation control algorithm has higher control accuracy and stability.