基于干扰观测器的解耦快速终端滑模控制

针对一类欠驱动系统跟踪控制问题,提出了一种基于非线性干扰观测器的全局解耦快速终端滑模控制(NDODGFTSMC)策略。将欠驱动系统分解成两个子系统分别设计全局快速终端滑模面,利用其中一个子系统滑模面的符号函数来构造中间变量,并将该变量引入到另一个子系统的滑模面中,构造出整个系统的滑模面,采用等效控制法和模糊双幂次趋近律求解系统的控制律。同时为了消除系统扰动对控制效果的影响,设计了一种双曲正切非线性干扰观测器对系统干扰进行估计并补偿给控制器。利用Lyapunov稳定原理证明了系统滑模面的渐近稳定性。将该方法应用于小车倒立摆系统的控制中,仿真结果验证了其有效性及优越性。

Decoupled Fast Terminal Sliding Mode Control Based on Disturbance Observer

For the tracking control problem of a class of under-actuated systems,a nonlinear disturbance observer-based decoupled global fast terminal sliding mode control(NDODGFTSMC) strategy is proposed in this paper.The under-actuated system is decomposed into two subsystems to design the global fast terminal sliding surface respectively.The intermediate variable is constructed by using the symbolic function of the sliding surface of one subsystem,and the variable is introduced into the sliding surface of the other subsystem to construct the sliding surface of the whole system.The equivalent control method and fuzzy double power reaching law are adopted to solve the control law of the system.Meanwhile,in order to eliminate the influence of system disturbance on the control effect,a hyperbolic tangent nonlinear disturbance observer is designed to estimate and compensate the system disturbance to the controller.The asymptotic stability of the sliding mode surface of the system is proved by Lyapunov stability principle.The simulation results show that the proposed method is effective and superior in the control of the car inverted pendulum system.