From RoboticsWiki

Contents 1 ICRA 2008 Workshop on Contact Models for Manipulation and Locomotion 1.1 Organizers 1.2 Overview 1.3 Motivation and objectives 1.4 List of topics 1.5 Confirmed Presenters and Schedule

ICRA 2008 Workshop on Contact Models for Manipulation and Locomotion

May 19, 2008

CALL FOR PARTICIPATION

Organizers

Todd Murphey Electrical and Computer Engineering University of Colorado at Boulder Boulder, CO 80309

Vijay Kumar Mechanical Engineering and Applied Mechanics University of Pennsylvania Philadelphia, PA 19104

Overview

This full-day workshop focuses on models of mechanical contact used in manipulation and locomotion for purposes of simulation and planning. Although modeling contact and friction is a well-studied area, the incorporation of mechanical contact into numerical models is still often achieved using heuristics. The goal of this workshop is to explore the role that different numerical techniques play in providing numerically stable simulations for purposes of prediction and planning, while maintaining the physical fidelity of the contact model. Subjects will include variational and complementarity representations of contact, topological methods in handling uncertainty in contact, and simplified models of contact for purposes of planning and control. Applications to be considered range from haptic interfaces for surgery to micro-scale manipulation, dexterous manipulation, and manufacturing processes.

Motivation and objectives

Mechanical contact is fundamental to many areas of robotics research, including autonomous vehicles, micro-scale assembly, minimally-invasive surgery, and haptic rendering for tele-operation. These applications require numerically efficient modeling techniques for the purposes of simulation, planning, and control. However, many current techniques invoke various heuristics for numerical implementation, often leading to either numerical instability or non-physical results. This indicates the need for a more systematic approach to modeling mechanical contact, including impacts and frictional interactions.

Recent work has addressed these shortcomings, but all in different manners and coming from rather different communities. The success of variational integrators in stably modeling impacts provides evidence that numerical integration based on energetic techniques can both be numerically efficient and directly based on physical principles. Modeling unilateral constraints arising from mechanical contact as a Linear or Nonlinear Complementarity Problem allows transitions between no-contact and contact, and between rolling and sliding to be handled in a transparent manner. Topological methods facilitate compliant motion and sensing in the presence of uncertainty. However, the insights from each of these techniques are still largely disconnected from each other.

This workshop will bring together the perspectives of researchers using these currently separate techniques for modeling mechanical contact. The goal of the workshop will be to promote combining these techniques into a more coherent and systematic approach to incorporating contact models into the description of complex tasks.

List of topics

• Contact modeling in manufacturing.
• Contact modeling in haptic interfaces for surgery.
• Variational integrators for contact and impact mechanics.
• Linear Complementarity Problem (LCP) representations of mechanical contact.
• Uncertainty in contact.
• Reduced-order representations of contact.
• Planning algorithms for systems that involve contact.
• Simplified models of contact for purposes of planning and control.

Confirmed Presenters and Schedule

08:15-08:30	Opening
08:30-09:30	Keynote Address: Jerrold Marsden (California Institute of Technology) Discrete Mechanics, Optimal Control and Robotic Walkers
09:35-10:00	Kevin Lynch (Northwestern University) Friction-Induced Lines of Attraction and Repulsion for Parts Sliding on an Oscillated Plate
10:00-10:25	Todd Murphey (University of Colorado) Constrained Rigid Body Simulation Using Graph-Based Variational Integrators
10:25-10:40	Ken Goldberg (University of California, Berkeley) Application: Manufacturing
10:40-11:00	break
11:00-11:25	Frank van der Stappen (Utrecht University) Design of Blades for Polyhedral Parts on Vibratory Tracks
11:25-11:50	Vijay Kumar (University of Pennsylvania) Planar Quasi-static Manipulation
11:50-12:15	Stephen Berard and Jeff Trinkle (Rensselaer Polytechnic Institute) An MPEC for Parameter Identification in Rigid Body Systems
12:15-12:40	Antonio Frisoli (Scuola S. Anna) A limit-curve based soft finger god-object algorithm for two fingers manipulation of virtual objects
12:40-14:10	lunch
14:10-14:25	Karl Böhringer (University of Washington) Application: MEMS Assembly
14:25-14:50	Jing Xiao (University of North Carolina—Charlotte) Contact States: Modeling, Search, and Simulation
14:50-15:15	Danny M. Kaufman (University of British Columbia) Coupled Principles for Contacting Systems
15:15-15:40	Eduardo Martin Moraud (INRIA), Joshua G.Hale and Gordon Cheng (ATR) Constraint-based Ground Contact Handling in Humanoid Robotics Simulation
15:40-16:00	break
16:00-16:15	Katherine Kuchenbecker (University of Pennsylvania) Application: Haptics
16:15-16:40	Liangjun Zhang and Dinesh Manocha (University of North Carolina) Contact Space Proximity and Planning Computations
16:40-17:05	Yizhar Or (California Institute of Technology), Elon Rimon and Daniel Meltz (Technion, Israel Inst. of Technology) Dynamic jamming - experimental demonstration of inconsistency in frictional rigid-body dynamics
17:05-18:00	panel discussion