Takagi-Sugeno Fuzzy Control for the Semi-active Seat Suspension with an Electromagnetic Damper

In this paper, a state observer-based Takagi-Sugeno (TS) fuzzy controller is proposed for a semi-active seat suspension installed with an electromagnetic damper (EMD) system. Due to the nonlinear and hysteresis characteristics of the seat suspension friction, the control system design for seat suspension is difficult. Therefore, the Bouc-Wen friction model is applied to represent the seat suspension friction force and this nonlinear model is linearized by using TS fuzzy approach at first. Then a H∞ controller that considers the seat suspension performance requirements is designed. It is noticed that not all the state variables are measurable in practice, a state observer is designed based on the measurement variables. Finally, two typical excitation are applied to validate the effectiveness of the proposed controller and a tuned passive suspension is also simulated for comparison.