Research on Fractional-Order Global Fast Terminal Sliding Mode Control of MDF Continuous Hot-Pressing Position Servo System Based on Adaptive RBF Neural Network

Abstract

In this paper, a novel fractional-order global fast terminal sliding mode control (FGFTSMC) strategy based on an adaptive radial basis function (RBF) neural network is proposed to improve the performance of a medium density fiberboard (MDF) continuous hot-pressing position servo system with parameter perturbation and external load disturbance. Primarily, the mathematical model of the MDF continuous hot-pressing position servo system is constructed based on the dynamic equation of the hydraulic system. Then, a FGFTSMC is designed to speed up the convergence rate of the system, in which an adaptive law is used to estimate the upper bound of the unknown parameters to overcome the existing parameter perturbation of the system. In addition, an RBF neural network is introduced to approximate the external load disturbance of the system. The stability of MDF continuous hot-pressing position servo system based on the control scheme developed in this paper is proven using the Lyapunov theory. Finally, the simulation results show that the presented control scheme can effectively ensure the tracking accuracy of the system and enhance the robustness of the system.

Dynamic Fractional-Order Nonsingular Terminal Super-Twisting Sliding Mode Control for a Low-Cost Humanoid Manipulator

“…Apart from introducing super-twisting algorithms, adding a fractional-order operator to the sliding mode controller is also an effective way to suppress chattering and improve motion control performance [32]. Applying a fractional-order (FO) operator to a sliding mode controller can enhance the flexibility of the controller, and improve its control performances [32][33][34][35][36]. Among all the fractional-order controllers, fractional-order nonsingular terminal sliding mode (FONTSM) controllers are widely used in manipulators to obtain precise position-tracking performance [37][38][39][40][41][42][43].…”