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Byline: Chen-Sheng Ting This paper introduces a fuzzy model-based control approach for vehicle lateral system with uncertainties. Based on the Takagi-Sugeno (T-S) fuzzy modelling approach, a robust observer-based fuzzy control scheme, which integrates optimal fuzzy control with H∞ control, is investigated. Sufficient conditions that ensure robust control performance of the system are derived and expressed in terms of Linear Matrix Inequalities (LMIs) such that the fuzzy controller can efficiently be synthesised. In particular, the given performance index function is not only minimised but also confined within a prescribed value. The proposed method is validated in the aspect of effectiveness and correctness via computer simulation.

This study presents an analytic designing approach for the sensorless direct thrust force control (DTFC) of permanent magnet linear synchronous motor (PMLSM). A modified stator flux estimator developed by use of an adaptive mechanism and correction factors is devoted to measuring the stator flux linkage and the mover's position. The parameters of the flux estimator are adjusted in advance through an off‐line identification process to increase the accuracy of estimation. Based on the principle of backstepping control, the reference q‐axis flux command, which is equivalent to the thrust force command, is first obtained from the Lyapunov functional analysis. Then, the reference d‐axis flux command is calculated according to the characteristics of stator flux linkage. The voltage control strategy is constructed to stabilise the global system and ensure the convergence of DTFC. Compared to the conventional direct torque/thrust control, the proposed control scheme can apply the space vector modulation to achieve a fixed switching frequency. Consequently, the phenomenon of flux and force ripples inherited from DTFC is improved. The experiment results are provided to validate the proposed control approach. Moreover, a recent work that is based on the optimal control is adopted as a comparison study. [ABSTRACT FROM AUTHOR]