The Nonsingular Terminal Sliding Mode Control And Its Application

The theory of Sliding Mode Variable Structure Control was presented in the1950s, and is gradually developed for nearly60years. In the system of Sliding Mode Variable Structure Control, the movement of Sliding mode has the quality of invariance for the system parameter perturbation and outside disturbance, Sliding Mode Variable Structure Control gradually becomes a kind of comprehensive method of control system, is suitable for the nonlinear system and uncertain system etc, and is also a kind of very good robust control method. But it also has its shortcomings and the insufficiency, such as the chattering problem. That is to say that when the system’s states move to the sliding surface, the system will produce high-frequency chattering phenomenon. According to this problem, this paper takes the corresponding solutions for different Sliding Mode Variable Structure Controls.After the reference to a large number of domestic and foreign documents about the theory of Sliding Mode Variable Structure Control, the paper introduces the basic principle and relevant content of Sliding Mode Variable Structure Control, and the Terminal Sliding Mode Variable Structure Control is deeply studied. The main content of the paper is as follows:First, the development of nonsingular terminal sliding mode control of the uncertain second-order system. The nonsingular terminal sliding mode could keep fast convergence of terminal sliding mode control and avoid singularity problem, is applied to second-order system with uncertainty control parameters, and design the corresponding sliding model variable structure control law. Sliding Mode Variable Structure Control has advantages, such as simple arithmetic, good robustness, fast response, easy engineering realization. Therefore, based on the second-order uncertain system of the roll channel in BTT missile, this paper puts forward Model reference singular terminal sliding model variable structure control scheme. The simulation results show that, the control systems of the roll channel in BTT missile could make tracking error of the system converge to the balance point in the limited time, effectively improve control precision, overcome the perturbation of pneumatic parameters in the big range and the effect of external disturbances and have good command tracking performance and strong robust properties.Second, the development of nonsingular terminal sliding mode control of the uncertain multivariable linear systems. To avoid the nonsingular problem of common terminal sliding mode and eliminate the inherent chattering problem of Sliding Mode Variable Structure Control, a dynamic nonsingular terminal sliding mode control method was brought forward for the uncertainty multivariable linear system, namely state transition of uncertainty multivariable linear system. Uncertainty multivariable linear system was more easily transformed into the system Consisted of an input/output subsystem and a stable inside subsystems by a kind of new state transform method. Corresponding dynamical nonsingular terminal sliding mode control law of the input and output subsystem could make the states of the subsystem converge to the balance point in the limited time and eliminate chattering phenomenon of the sliding mode.At last, we make a summary for the work of the paper, then the problems that need to be resolved in the future are presented and the future research directions are proposed.