Coupled anti-swing control strategy for underactuated tower cranes with obstacle avoidance

Abstract

To achieve precise positioning, anti-swing control, and obstacle avoidance for tower cranes, this paper addresses the problem of coupled anti-swing and obstacle avoidance control in underactuated nonlinear systems. First, a trajectory modification method is introduced to ensure avoidance of irregular obstacles while maintaining sufficient differentiability. Then, a dynamic performance boundary is defined to constrain load angles based on low-pass filters. Finally, by coupling actuated and non-actuated states, a tracking controller is designed and applied to a laboratory tower crane. The proposed controller can not only achieve precise positioning and obstacle avoidance for loads, but also always constrain load swing angles within predefined ranges. The developed control scheme can improve the control accuracy and work efficiency of tower cranes, simultaneously. In future, the proposed controller will be applied to tower cranes for three-dimensional obstacle avoidance.