6 DOF path planning in dynamic environments-a parallel online approach

Presents an approach to parallel path planning for industrial robot arms with six degrees of freedom in an online given 3D environment. The method is based a best-first search algorithm and needs no essential off-line computations. The algorithm works in an implicitly discrete configuration space. Collisions are detected in the Cartesian workspace by hierarchical distance computation based on polyhedral models of the robot and the obstacles. By decomposing the 6D configuration space into hypercubes and cyclically mapping them onto multiple processing units, a good load distribution can be achieved. We have implemented the parallel path planner on a workstation cluster with 9 PCs and tested the planner for several benchmark environments. With optimal discretisation, the new approach usually shows very good speedups. In online provided environments with static obstacles, the parallel planning times are only a few seconds.

[1]  Dominik Henrich,et al.  Fast Motion Planning by Parallel Processing – a Review , 1997, J. Intell. Robotic Syst..

[2]  Narendra Ahuja,et al.  Gross motion planning—a survey , 1992, CSUR.

[3]  Heinz Wörn,et al.  Schnelle Kollisionserkennung durch parallele Abstandsberechnung , 1997, AMS.

[4]  Nils J. Nilsson,et al.  A Formal Basis for the Heuristic Determination of Minimum Cost Paths , 1968, IEEE Trans. Syst. Sci. Cybern..

[5]  Prof. Dr. Kikuo Fujimura.  Motion Planning in Dynamic Environments , 1991, Computer Science Workbench.

[6]  Dominik Henrich,et al.  Path planning for industrial robot arms - A parallel randomized approach , 1996 .

[7]  Angel P. del Pobil,et al.  Practical Motion Planning in Robotics: Current Approaches and Future Directions , 1998 .

[8]  Christian Wurll,et al.  Ein Workstation - Cluster fuer paralleles Rechnen in Robotik-Anwendungen , 1997 .

[9]  Dominik Henrich,et al.  Parallele Bewegungsplanung in dynamischen Umgebungen , 1997 .

[10]  Dominik Henrich,et al.  Fast distance computation for on-line collision detection with multi-arm robots , 1992, Proceedings 1992 IEEE International Conference on Robotics and Automation.

[11]  Heinz Wörn,et al.  Automatic off-line programming and motion planning for industrial robots , 1998 .

[12]  Ben J. H. Verwer,et al.  A multiresolution work space, multiresolution configuration space approach to solve the path planning problem , 1990, Proceedings., IEEE International Conference on Robotics and Automation.

[13]  Heinz Wörn,et al.  Multi-Directional Search with Goal Switching for Robot Path Planning , 1998, IEA/AIE.

[14]  Paolo Fiorini,et al.  Time optimal trajectory planning in dynamic environments , 1996, Proceedings of IEEE International Conference on Robotics and Automation.

[15]  Gerd Hirzinger,et al.  A global and resolution complete path planner for up to 6DOF robot manipulators , 1996, Proceedings of IEEE International Conference on Robotics and Automation.