Orienting Toleranced Polygonal Parts

Srinivas Akella and Matthew T. Mason
International Journal of Robotics Research, Vol. 19, No. 12, December, 2000, pp. 1147-1170.


Download
  • Adobe portable document format (pdf) (409KB)
Copyright notice: This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. These works may not be reposted without the explicit permission of the copyright holder.

Abstract
Parts manufactured to tolerances have variations in shape. Most previous work in robotic manipulation assumes that parts do not have shape variations. Orienting devices such as bowl feeders often fail due to variations in part shape. We study the effects of uncertainty in part shape on orienting to develop systems that can orient toleranced polygonal parts. We present a tolerance model in which the part center of mass and vertices lie in circular uncertainty zones around their nominal positions. The variations in part shape are characterized by the tolerance model and the part's nominal shape. We describe the nondeterminism that arises due to part shape uncertainty for a conveyor-based orienting system and show that sensor-based and sensorless orienting plans can exist for toleranced polygonal parts. We present implemented planners that generate orienting plans for the entire variational class of part shapes given a nominal part shape and tolerance bounds. These plans use both deterministic and nondeterministic actions to orient the parts, and we describe experiments to demonstrate them.

Keywords
parts orienting, tolerancing, flexible assembly, manufacturing

Notes
Number of pages: 24

Text Reference
Srinivas Akella and Matthew T. Mason, "Orienting Toleranced Polygonal Parts," International Journal of Robotics Research, Vol. 19, No. 12, December, 2000, pp. 1147-1170.

BibTeX Reference
@article{Akella_2000_3840,
   author = "Srinivas Akella and Matthew T. Mason",
   title = "Orienting Toleranced Polygonal Parts",
   journal = "International Journal of Robotics Research",
   pages = "1147-1170",
   publisher = "Sage Science Press",
   month = "December",
   year = "2000",
   volume = "19",
   number = "12",
}