Three dimensional path planning using potential method for overhead crane

摘要

This paper presents a method for path planning and motion execution of overhead travelling crane with three dimensional transport, considering the both of obstacle avoidance and suppression of sway for transfer objects. The present research is done based on a given geometrical map in environments for off line application, as the basic step to establish autonomous mobile crane systems in future factory. A potential approach using a three dimensional diffusion equation is applied to the present path planning. The moving direction and magnitude in each step are respectively calculated by the proposed vector composite method and the allowable maximum values of acceleration and velocity constrained from the hardware capacity. Further, in order to avoid the collision with obstacles especially around the steep corner, a holding method is proposed by the introduction of the concept of a steering angle between the moving direction at the present position and the direction to he moved calculated from the potential field at the stopping position of some-step ahead. The usefulness of this paper is demonstrated through computer simulations and laboratory experiments.