Sliding Mode Control for Nonholonomic Mobile Robot Formation
YU Hui1,2, WANG Yong-ji1, XU Jian-sheng1
1. Department of Control Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China; 2. College of Science, China Three Gorges University, Yichang 443002, China
Abstract：A nonlinear sliding mode controller is proposed to coordinate a group of nonholonomic mobile robots so that a desired formation can be achieved.By using sliding mode control approaches,we consider a two-vehicle team in leader-(follower) configuration that is required to follow a prescribed trajectory while maintaining a desired relative distance,relative bearing angle and heading orientation.Stability of the closed-loop system are studied using classical Lyapunov theory.We prove theoretically that under certain reasonable assumptions the formation is asymptotically stable even with bounded disturbances;that is,the proposed sliding mode controller can asymptotically stabilize the errors in relative distance,relative bearing and heading direction,respectively.Finally,a numerical simulation example is given for the two-robot case to verify the validity of our approach.
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