A Time-optimal Trajectory Control Method for Bridge Cranes with Conditional Constraints

To improve the efficiency and safety of transportation process, a new trajectory planning method of nonlinear bridge crane system based on swing constraint is proposed in this paper. The trajectory owns the following advantages: 1) Guide the trolley to reach the destination at a fast enough speed; 2) Keep the swing of the payload in an acceptable range. 3) Eliminate residual swing when the trolley stops at the desired position. Specifically, the movement of payloads is divided into four stages. According to the requirements of anti-swing and zero residual swing in each stage, the trajectory of swing Angle is directly constructed, and the trajectory of the trolley is obtained by analyzing the nonlinear kinematics of the bridge crane system. In addition, transport time, maximum swing angle and other indicators need to be further optimized. Finally, the performance of the proposed trajectory planning method based on pendulum Angle constraint is verified by simulation experiments.