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Motion Algorithms: Planning, Simulating, Analyzing Motion of Physical Objects. Jean-Claude Latombe Computer Science Department Stanford University. Pernes-les-Fontaines. About Myself. Born a long time ago in South-East of France. About Myself. Born a long time ago in South-East of France
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Motion Algorithms:Planning, Simulating, Analyzing Motion of Physical Objects Jean-Claude Latombe Computer Science Department Stanford University
Pernes-les-Fontaines About Myself • Born a long time ago in South-East of France
About Myself • Born a long time ago in South-East of France • Studied in Grenoble(Eng. EE, MS EE, PhD CS 1977) • CS Professor, Grenoble (1980-84) • CEO, ITMI (1984-87) • Stanford (1987-…)
Research Interests • 1980-84: Artificial Intelligence, Computer Vision, Robotics • 1987-92: Robot Motion Planning • 1993-98: Motion Planning • 1998-…: Motion Algorithms
Fundamental Question Are two given points connected by a path?
How Do You Get There? • Problems: • Geometric complexity • Space dimensionality
Assembly planning Target finding New Problems
Space Robots robot obstacles air thrusters gas tank air bearing
Modular Reconfigurable Robots Casal and Yim, 1999 Xerox, Parc
Humanoid Robot [Kuffner and Inoue, 2000] (U. Tokyo) Stability constraints
Study of Molecular Motion Ligand binding Protein folding
Basic Tool: Configuration Space Approximate the free space by random sampling Probabilistic Roadmaps [Lozano-Perez, 80]
Probabilistic Roadmap (PRM) free space
local path milestone mg mb Probabilistic Roadmap (PRM) free space
[Quinlan, 94; Gottschalk, Lin, Manocha, 96] First Assumption of PRM Planning Collision tests can be done efficiently. Several thousand collision checks per second for 2 objects of 500,000 triangles each on a 1-GHz PC
Exact Collision Checking of Path Segments • Idea: Use distance computation in workspace rather than pure collision checking D= 2Lx|dq1|+L|dq2| 3Lxmax{|dq1|,|dq2|} If D d then no collision d q2 q1
Second Assumption of PRM Planning A relatively small number of milestones and local paths are sufficient to capture the connectivity of the free space.
Probabilistic Completeness In an expansive space, the probability that a PRM planner fails to find a path when one exists goes to 0 exponentially in the number of milestones (~ running time).
vi Pij vj Application to Biology Markov chain + first-step analysis ensemble properties
Current Projects • Robot motion planningFunding: General Motors, ABBCollaborator: Prinz (ME), Rock (AA) • Study of molecular motions (folding, binding)Funding: NSF-ITR (with Duke and UNC), BioXCollaborators: Guibas (CS), Brutlag (Biochemistry), Levitt (Structural Biology), Pande (Chemistry), Lee (Cellular B.) • Surgical simulation (deformable tissue, suturing, visual and haptic feedback)Funding: NSF, NIH, BioXCollaborators: Salisbury (CS+Surgery), Girod (Surgery), Krummel (Surgery) • Modeling and simulation of deformable objectsFunding: NSF-ITR (with UPenn and Rice)Collaborators: Guibas (CS), Fedkiw (CS)
Tadjikistan Pakistan Afghanistan Third Pillar of Dana (California) Cho-Oyu, 8200m, ~27,000ft (Tibet) Muztagh Ata, 7,600m, 25,000ft (Xinjiang, China) Thailand
Rock-Climbing Robot With Tim Bretl and Prof. Steve Rock
Half-Dome, NW Face, Summer of 2010 … Tim Bretl