Oscillation attenuation for crane payloads by controlling the rope length using extended linearization techniques

Abstract

Oscillation attenuation is an essential task for practically any crane application. Classically, such control strategies make use of the actuation of a crane trolley to counteract the motion of a swinging payload. As an alternative to controlling trolley motions, variations of the rope length can be considered. In contrast to scenarios where trolley motions are used to attenuate oscillations, the control of the rope length is a more challenging task due to non-negligible nonlinearities and due to the presence of points in the state-space for which controllability is not guaranteed. In this paper, a novel extended linearization approach is presented for the oscillation attenuation in crane systems, where the feedback gains are determined by using a robust optimization procedure which employs a formulation of the control task in terms of linear matrix inequalities. Simulation results and an experimental validation highlight the practical applicability of the proposed control procedure.