Antisway Control for a Rotary Crane by Using Evolutionary Computation

Abstract

We present a simple antisway control method for a rotary crane, whose load can move in a two-dimensional plane. In particular, we investigate the suppression of residual sway motion of a rotary crane with a boom that performs point-to-point motion. In the proposed method, we attempt to generate the trajectory of the boom using a combination of polynomial and cycloidal functions. The profile of the generated trajectory depends on the coefficients of the polynomial function. Thus, it is necessary to tune the coefficients to minimize the sway motion in the two-dimensional plane as much as possible. We adopt a particle swarm optimization algorithm, an evolutionary computation technique, to tune the coefficients and then obtain the optimal trajectory. By rotating the boom along the optimal trajectory, the two-dimensional residual sway motion is suppressed, i.e., an open-loop control is realized. The effectiveness and feasibility of the proposed control scheme is demonstrated via simulations and experiments.