Open Problems

1. Autoplace: locate the robot base to minimize total travel time.

2. Cable Routing: route cables to minimize total turning angle.

3. Design of Gripper Jaws: given set of grasps on known parts.

4. Completeness of Fences for Feeding Parts.

5. Grasp-Circuit Planning: rapidly schedule efficient load paths.

Recent Articles

A Complete Algorithm for Designing Passive Fences to Orient Parts, (with J. Wiegley, M. Peshkin, and M. Brokowski), Assembly Automation, 17:2, August, 1997.

On the Existence of Solutions in Modular Fixturing, (with Y. Zhuang), International Journal of Robotics Research, 15:5, December 1996.

Computing Grasp Functions, (with A. Rao), Computational Geometry and Applications, 6, May 1996.

Complete Algorithms for Feeding Polyhedral Parts using Pivot Grasps, (with A. Rao and D. Kriegman), IEEE Transactions on Robotics and Automation. 12(2), April, 1996.

A Complete Algorithm for Designing Modular Fixtures Using Modular Components, (with R. Brost), IEEE Transactions on Robotics and Automation. 12(1), February, 1996.

Beyond the Web: Manipulating the Real World, (with M. Mascha, S. Gentner, J. Rossman, N. Rothenberg, C. Sutter and J. Wiegley), Computer Networks and ISDN Systems Journal, 28(1), December 1995.

Manipulating Algebraic Parts in the Plane, (with A.Rao), IEEE Transactions on Robotics and Automation, 11(4), August 1995.

Recent Articles

A RISC Approach to Sensing and Manipulation, (with J. Canny), Journal of Robotic Systems, Special Issue edited by J. McCarthy and F. Park, V12(6), June 1995.

Computing Fence Designs for Orienting Parts, (with R.P. Berretty and F. van der Stappen and M. Overmars), Computational Geometry and Applications, Accepted March 1998.

Algorithms for Sensorless Manipulation Using a Vibrating Surface (with K. Bohringer and V. Bhatt and B. Donald),Algorithmica, Accepted November 1997.

Geometric Eccentricity and the Complexity of Manipulation Plans, (with F. van der Stappen and M. Overmars), Algorithmica, Accepted September 1997.

Ken Goldberg: ALPHA Lab

UC Berkeley

“The smartest assembly robot and the best assembly machine in the world are useless without the mechanism that delivers the part” - Bill Davis, Feeder Systems

Sponsors: National Science Foundation, Adept Technology, General Motors, Intel, and HP.

http://www.ieor.berkeley.edu/~goldberg

Assembly Line Part Handling Algorithms

Sorting Polygonal Parts with an Instrumented Parallel-Jaw Gripper

Duk Kang and Anil Rao and Ken Goldberg (USC)

Random grasping (Kand and Goldberg 1992)Drawback: Inefficient

Analytical Planner (Rao and Goldberg, 1992)Drawback: Requires CAD Models

Open Problems

• Can we orient any planar part up to symmetry using parallel-jaw grippers (i.e., parts with algebraic contours)?

• Is there a polynomial-time algorithm to find the shortest plan for sorting parts with an instrumented parallel-jaw gripper?

• Parts can be oriented with a sequence of fences as they pass on a conveyor belt. Are frictionless fences complete for the class of Polygonal Parts? (Is there a part we cannot orient with fences?)

• What is a lower bound on the complexity of designing modular fixtures? For what class of parts are modular fixtures complete?

• Given a known set of part, can we locate a registration mark on each part to efficiently distinguish them?

• Stable poses of 3D curved parts: Given a CSG part (constructed by negation, union, and intersection operations on n primitive solids) with its center of mass, what is the complexity of finding all stable poses of the part on a flat surface?

• Given a family of parts, choose a beam layout to minimize the probability of mis-identification of parts and mis-calculation of pose.

• Model generation: Using a sequence of probes with a moving beam sensor, plan a strategy for determining the shadow of a part for recognition by a parallel-beam sensor.

• Pose determination from sparse depth probes. Given k fixed depth probes, determine part identity and pose given part models. (We are experimenting with simple beam arrays that will provide this data.)

• Given polyhedral part shape, design a “pallet” such that parts flowing over the pallet will fall into the pallet in a unique orientation and are prevented from jamming.

Fig. 2 APOS

Publications

Algorithmic Foundations of Robotics, (co-edited with D. Halperin, J-C. Latombe, and R. Wilson), 1995.

Manipulating Algebraic Parts in the Plane, (with A. Rao), 1995.

A Complete Algorithm for designing Modular Fixtures for Polygonal Parts, (with R. Brost), 1995.

A RISC Approach to Sensing and Manipulation, (with J. Canny), 1995.

Placing Registration Marks, (with A. Rao), 1994.

Shape from Diameter: Recognizing Polygonal Parts with Parallel Jaw Gripper, (with A. Rao), 1994.

Orienting Polygonal Parts without Sensors, 1993.