Time-Optimal Trajectory Generation of Rotary Cranes with Collision Avoidance

Abstract

This paper presents a new three-dimensional trajectory generation method for a rotary crane using a simple dynamics model. The proposed trajectory achieves fast motion and suppresses load-sway with obstacle avoidance, which is generated by a combination of the A* algorithm and a time-optimization approach. The former is used to generate a shortest-distance path for a transported load considering obstacle avoidance. The time-optimization scheme is applied to the path generated by the A* algorithm under crane dynamics and load-sway constraints. The proposed trajectory is represented by a polynomial function to provide smooth and practical motion. Simulation results demonstrate the effectiveness on load-sway suppression and obstacle avoidance.