Adaptive sliding mode control with fuzzy adjustment of switching term based on the Takagi-Sugeno model for horizontal vibration of the high-speed elevator cabin system

In purpose of reducing the severe horizontal vibration of the high-speed elevator car system which is caused by the excitation of the guide rail, an adaptive sliding mode controller with fuzzy switching gain (FGASMC) is designed in this paper. At first, a 4-DOF active control dynamics model of the horizontal vibration of the elevator car is designed, on which the actuators are symmetrically distributed around the cabin center, and the accuracy of which is demonstrated by experiments. Considering the uncertainty caused by the load conditions, structural mass of the elevator, and the output gain of actuators, a Takagi-Sugeno (TS) model for controlling horizontal vibration of the car system is derived based on the designed 4-DOF dynamics model. Then, based on the TS model mentioned above, an adaptive sliding mode controller (ASMC) for suppressing the horizontal vibration of the car system is designed by a quadratic index method. To ensure the reachability of the sliding mode and keep the chattering smaller, the fuzzy method is utilized to adjust the switching gain of the ASMC. For that, an FGASMC is proposed. Finally, the effectiveness of the proposed controller is verified by MATLAB simulation. The results illustrate that the designed FGASMC can effectively suppress horizontal vibration of the high-speed elevator car system, and the control effect of which is obviously superior than the linear quadratic regulator optimized by genetic algorithm, which provides a new idea for active vibration reduction of high-speed elevator car.