Research On Sliding Mode Control Algorithm For Cricket System

The Ball and Plate system can be regarded as the extension of the Ball and Beam system in the two-dimensional space.A complex system with multi-DOF,the Ball and Plate system is often used as an important experimental object for theoretical research in the field of control,and is used to verify the performance of various control algorithms.As a common control method in nonlinear system control is Sliding Mode Control(SMC),and its particularity lies in the discontinuity of its control process.This discontinuity makes the state of the controlled system move up and down quickly in a small range along the trajectory.It is this kind of discontinuity that makes the sliding mode control has good robustness,but it will cause chattering problems in the system.This paper takes the Ball and Plate system as the control object to study the sliding mode control algorithm,focusing on the problems of large chatter and large error in trajectory tracking control of the Ball and Plate system,as well as the sliding mode control chattering problem and the approach speed of the sliding mode reaching law.The main work of this paper is as follows:Firstly,based on the fuzzy sliding mode control method,the idea of variable universe and adaptive control are integrated into the control of the Ball and Plate system,and a variable universe adaptive fuzzy sliding mode controller is designed for the mathematical model of the Ball and Plate system.Among them,on the variable universe fuzzy control,the input and output variable universe can be adjusted online to achieve the approximation of the sliding mode switching control coefficient.The control accuracy and dynamic response can be improved in the process of contraction and extension,and the switching gain can be adjusted adaptively to reduce as much as possible,so as to improve the control performance and weaken the chattering.Then,due to the reaching law sliding mode controller method,the dynamic motion quality of the system can be effectively improved in the reaching process,a variable exponential power reaching law is proposed.The nonlinear combination function and variable exponential term in the reaching law can accelerate the convergence speed when it is far away from and close to the sliding surface,and can make the system state approach the sliding surface from arbitrary initial position within a finite time range.The exponential parameters of the variable exponential power reaching law can be adjusted adaptively in different response stages of the control system.The convergence of the variable exponential power reaching law is compared with other reaching laws,and the trajectory tracking simulation experiment of the Ball and Plate system is carried out.Finally,aiming at the slower convergence speed of terminal sliding mode control when approaching the sliding mode surface,a complementary terminal sliding mode control method is proposed to improve the quality of the control system.Combining the variable exponential power approaching law,a new sliding mode control scheme of the Ball and Plate system is proposed.In order to verify the effectiveness and superiority of the Ball and Plate system sliding mode control scheme,comparative simulation experiments are designed for analysis.In the case of the same sliding mode reaching law,the complementary terminal sliding mode control,the terminal sliding mode control,the complementary sliding mode control and the traditional sliding mode control are compared in the trajectory tracking simulation experiment of the Ball and Plate system,and each control schemes are analyzed.