Skidding Mechanical Model And Control Method Research Of Wheel Mobile Robot

Wheel Mobile Robot is a ground mobile platform of autonomous driving and perceiving surrounding through sensors,which can achieve trajectory tracking even when suffering disturbance from around environment.Since WMR is high intelligent,it is often used to arrive dangerous place to finish tasks.With the development of science and technology,WMR has attracted more and more peoples' attention.Since WMR usually drive on non-structured and low-adhesion road,it often encounters slipping and skidding,thus making WMR deviate from the ideal trajectory.So how to deal with slippage and skidding is key point of this paper.At first,derivate the position error partial differential equation when WMR suffers skidding and establish the kinematic model of WMR.Introduce sliding parameters to establish the kinematic model of WMR when it suffers slippage.In addition,establish WMR's dynamic model with Euler-Lagrange energy method.In order to eliminate nonholonomic constraint,it's necessary to reduce order thus designing the controller more easily.Also,the WMR ground friction model with wheel-road friction interference can be established.Secondly,for the WMR skidding model,we can design controller with Lyapunov direct method and Sliding mode control method separately.Compare and analyze which control method can make tracking error convergence more fast,thus achieving trajectory tracking.Thirdly,for the WMR slipping model,we can design controller from kinematics level and dynamic level separately.The kinematics controller design uses Lyapunov direct method,and the dynamic controller design uses RBF neural network technology.At last,it's necessary to put up double closed loop to achieve position tracking in inner loop and velocity tracking in outer loop.In adition,sliding model technology and terminal sliding model technology are used in inner loop and compare the two control methods' s convergence properties.By using the Lyapunov stability theorem,La Salle invariance theorem and Babalate lemma,the stability of control system above has been verified.In order to verify the effectiveness and feasibility of controllers designed above,MATLAB has been used to finish simulation analysis.This study can significantly improve the WMR's adaptability in complex unstructured environment,thus having double values of theoretical research and practical application.