General Criterion And Control Strategy Of Collision-free Movement For Manipulators

In this paper, we present a general procedure for finding collision-free paths for a polyhedral object moving through space that is cluttered with obstacle polyhedra. The unified criterion of collision- free motion is represented as Conv {H/sub i/)Conv {O/sub j/)=/spl Oslash/ which is suitable for all cases regardless of the space dimensionality. Based on the criterion, we are led to construct the describing function J which stands for minimal distance between the moving object and obstacles. Tha algorithm derived from describing function J can be used to find any path of interest for both the 2-D problem and the 3-D problem. It is shown that the solution method to the find path problem may be reduced to a search technique. Since the describing function J is related to only some extreme points, the strategy for automatically determining safe paths between configurations in presence of obstacles may be effectively sets implemented by a simple programming.