An efficient algorithm (FAPRIC) for finding the principal contacts possibly established due to uncertainties

An implemented algorithm is presented for finding all principal contacts possibly established between two surface features (i.e. faces, edges, or vertices) of two polyhedral objects due to location (i.e. position and orientation) uncertainties. The algorithm FAPRIC (finding all principal contacts) requires as inputs: the estimated locations of the two objects, the geometric models of the objects, and the bounds on position and orientation uncertainties. The algorithm is based on checking intersections between the grown regions of the objects by location uncertainties with the S-tope model. It is very efficient and apt for real-time processing. The information obtained can serve as a guide for more accurate extraction and further reasoning of the contact data, possibly with additional sensors. As the surface of an arbitrary object can be approximated by planar patches, the algorithm can also be applied to general objects. The work is motivated by the need for automatically recognizing contacts in spite of uncertainties in robotic tasks