Cooperative Formation And Path Planning Of Multiple Mobile Robots

At present,it can be seen that robots have come into the vision of the public,in which multi-robot technology has become an important research direction in the field of robots.Since it is applied in many fields,it has attracted the attention of many experts and scholars.In this thesis,it carries out an in-depth research on the cooperative formation and path planning of multiple mobile robots as an important aspect of robot research.1)Through the establishment of the global and local coordinate system of mobile robot,it proves its nonholonomic constraints.By virtue of the kinematics and dynamics model of mobile robot,it deduces the navigation following model of distance-distance and distance-angled,which lays the model foundation for the follow-up exploration.2)To solve the problem of discontinuity and unsmoothness in the existing genetic algorithm for mobile robot path planning,it puts forward an improved genetic algorithm.Firstly,it adopts the maximum likelihood estimation method and grid method to complete the localization and path modeling of the mobile robot.Secondly,it deletes and inserts the redundant and discontinuous path points generated by the initial path and the four quadrant selection principle,which also considers the smoothness function coefficient of the path in the fitness function.Then,it uses the improved NSGA-II algorithm to optimize the multiple mobile robots.Finally,it puts forward a new adaptive adjustment strategy,which mainly make self-adjustment of the values of crossover and mutation operators.By using this strategy,it can significantly improve the convergence speed of the algorithm,and finally get a better path.3)In view of the cooperative communication problem encountered by multiple mobile robots in formation,it adopts the decentralized control method.At the same time,it proposes an improved global asymptotic stability control method to improve the tracking accuracy of mobile robots.Firstly,it uses backstepping method to analyze the trajectory tracking based on the kinematics of mobile robots.Secondly,it adopts the sliding mode control method to establish the dynamic controller of mobile robot,so as to design a stronger global asymptotic trajectory tracker.Then,it uses the Lyapunov function to prove the stability of the nonlinear system of multiple mobile robots,so that the tracking error of the system converges asymptotically to the zero point.Finally,it completes the global stable tracking of the reference preset trajectory by multiple mobile robot.4)Furthermore,it carries out the research on the multiple mobile robot formation.By taking the distance-angle navigation following model as the basis,it introduces the ideal following mobile robot.At this time,the pilot mobile robot should use the improved genetic algorithm to plan a better path from the starting point to the ending point,while the actual follow-up mobile robot should use the formation coordination strategy to avoid obstacles and the minimum fault-tolerant distance collision avoidance strategy for formation control.According to the results,it indicates that the application of the improved navigation following formation control algorithm to the formation of multiple mobile robots can not only make them avoid obstacles,but also can make them form formation automatically.