Gain-scheduled H∞ loop-shaping controller for automated guidance of tractor-semitrailer combination vehicles

Deals with the robust, gain-scheduled, lateral control problem for tractor-semitrailer combination vehicles (TSCVs) using an observer-structured H_∞ loop-shaping controller. Vehicle longitudinal speed is chosen as the scheduling parameter since variations of speeds dramatically change system dynamics in different frequency ranges. By utilizing the vehicle speed as the scheduling parameter, the controller minimizes the effect of uncertainties and nonlinearities, which depends mainly on the velocity. Two scheduling techniques are applied to evaluate the effectiveness of the proposed controller. Simulation shows that the gain-scheduled controller generally sustains a larger robustness region than the fixed-gain linear controller under the uncertainties of varying road adhesion coefficients and cargo loads in the trailer