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Derby, Stephen J.

Publications and source records attributed to Derby, Stephen J..

Application of the CIRSSE cooperating robot path planner to the NASA Langley truss assembly problem

A method for autonomously planning collision free paths for two cooperating robots in a static environment was developed at the Center for Intelligent Robotic Systems for Space Exploration (CIRSSE). The method utilizes a divide-and-conquer type of heuristic and involves non-exhaustive mapping of configuration space. While there is no guarantee of finding a solution, the planner was successfully applied to a variety of problems including two cooperating 9 degrees of freedom (dof) robots. Although developed primarily for cooperating robots the method is also applicable to single robot path planning problems. A single 6 dof version of the planner was implemented for the truss assembly east, at NASA Langley's Automated Structural Assembly Lab (ASAL). The results indicate that the planner could be very useful in addressing the ASAL path planning problem and that further work along these lines is warranted.

Weaver, Jonathan M.↗

A method for planning collision free trajectories for two cooperating robots

Robotic systems designed specifically for space applications often exhibit a high level of autonomy to reduce the costs associated with having humans in space. This paper presents a method for autonomously planning collision free paths for two cooperating robots in a static environment. The method performs selective mapping of configuration space while attempting to locate a safe path. The method is based around an algorithm aimed at transversing a space of arbitrary dimension which contains both safe and unsafe regions. While the procedure cannot guarantee finding a solution even if one may exist, it is intended to find a solution to many practical path planning problems within a reasonable amount of time. Results are presented for applying the procedure to two cooperating six degree of freedom manipulators (Puma 560s).

Weaver, Jonathan M.↗