1. CS 326 A: Motion Planning http://robotics.stanford.edu/~latombe/cs326/2003 Exploring and Inspecting Environments

2. Criticality-Based Motion Planning C-space, Motion space, … Define property P Find where P changes  geometric arrangement: - critical curves/surfaces, - regular regions (cells)

3. Criticality-Based Motion Planning Property P: Is closest to a single point in the obstacle boundary

4. Criticality-Based Motion Planning Property P: Blocking relation among parts

5. Goal d 1 (L-Left Touch) d 2 (L-Right Exit) Criticality-Based Motion Planning

6. Start Goal

7. Criticality-Based Motion Planning

8. (Part orientation – Goldberg)

9. Criticality-Based Motion Planning (target finding)

10. Approach is practical only in low- dimensional spaces: - Combinatorial complexity of geometric arrangement - Sensitivity to floating-point computation errors (see European CGAL project) Criticality-Based Motion Planning

11. Today’s Papers  Planning of inspection paths: T. Danner and L.E. Kavraki. Randomized Planning for Short Inspection Paths. IEEE Int. Conf. on Robotics & Autom., San Francisco, April 2000.  Art gallery + PRM + TSP  Target finding: - S. LaValle et al.. Visibility-Based Pursuit-Evasion in a Polygonal Environment. 5th Workshop on Algorihtms and Data Structures, 1997. - S.M. LaValle et al.. Finding an Unpredictable Target in a Workspace with Obstacles. IEEE Int. Conf. on Robotics & Autom., 1997.  Criticality-based planning + information state space