Minimum-Time Trajectory Optimization for Underactuated Overhead Crane Under Disturbances

In this paper, an online minimum-time trajectory optimization (OMTTO) method is proposed for underactuated overhead cranes. This is a time-optimal solution for planning the trajectory of overhead crane systems, which simultaneously takes into account various constraints, including the bounded swing angle of the payload, the bounded speed, and the acceleration of the trolley. Unlike the existing methods, the time-optimal solution is found by using the Hermite-Simpson collocation method, bisection method, segmentation method, and disturbance observer, which satisfy all the above constraints while effectively removing the external environmental disturbances and solving the time-dependent problem of the online solution. Extensive simulations are performed and compared with previously published methods to show the superior performance of the proposed method.