Gain-Scheduled Controller Design: Illustration on an Overhead Crane

This paper extends a recently developed interpolation-based approach to design gain-scheduled controllers for linear parameter-varying systems with a thorough evaluation, comprising both simulations and experiments, on an overhead crane system. In the first step of the approach, linear time-invariant controllers are designed for local working conditions of the system using a multiobjective H_∞ method. With the help of this method, the fundamental tradeoff between reference tracking and disturbance rejection in the overhead crane control problem is analyzed. In the second step, a state-space interpolation method is used to calculate a gain-scheduled controller. Although this approach does not guarantee stability and performance under parameter variations, experiments on the crane setup show that these variations do not compromise the performance of the obtained controller.