Research On Motion Planning And Trajectory Tracking Control Of Omnidirectional Mobile Robots

Path planning and tracking control are two very important problems in the field of mobile robots,and are prerequisites for mobile robots to accomplish other complex tasks.With the development of artificial intelligence and the progress of technology,how to quickly and effectively find an optimal path in known or unknown environment and accurately track the trajectory has become an indivisible part of the research of mobile robots.In this paper,we mainly study path planning,path smoothing and trajectory tracking in unknown environment.A RSP_Q learning path planning method based on virtual subtarget path is proposed.The production trajectory was smoothed using the B-spline method.Then the trajectory tracking control is designed according to the backstepping method.First,aiming at the difficulty of autonomous mobile robot navigation in unknown dynamic environment,reinforcement learning is introduced.The model based RL approach is beneficial in learning speed and perform well in a stationary environment,but if the environment changes,the learning model may block the learning process in the new environment.The RL method works well in a changing environment without the need for an environment model,but model free methods are very inefficient in using the collected data,so it usually requires a large number of data from the trial and error to get good performance.In this paper,based on the advantages of model based and model free methods,a RSP_Q learning algorithm based on virtual subtarget is proposed based on the fast learning speed of the model and the strong adaptability of the model to the environment.The algorithm is compared with other strong learning methods in the simulation experiment,and the algorithm is proved.The superiority of the system.Secondly,the path planned by the RSP_Q learning algorithm based on the virtual subtarget is connected by a series of line segments,and the discontinuous change of curvature at the two line segments leads to the mobile robot needing a pause to adjust the position and posture when passing through these places,thus affecting the fluency of the mobile robot.In this paper,the B spline method is used to smooth the trajectory of mobile robot planning,so that the mobile robot can track the trajectory smoothly,and the simulation experiment is carried out in the MATLAB to verify the practicability of the trajectory smoothing.Thirdly,through the kinematic analysis of the omnidirectional mobile robot,the trajectory tracking control law of this system is designed to track the reference trajectory,and the line trajectory,the arc trajectory and the square track are tracked in the simulation experiment,and the error of the parameters in the tracking process is analyzed.The difference rate verifies the feasibility of the control lawFinally,we verified the feasibility and robustness of the algorithm by using the mobile platform.