The Navigation System of the JPL Robot

Abstract

The control structure of the JPL research robot and the operations of the navigation subsystem are discussed. The robot functions as a network of interacting concurrent processes distributed among several computers and coordinated by a central executive. The results of scene analysis are used to create a segmented terrain model in which surface regions are classified by traversibility. The m:>del is used by a pathplanning algorithm, PATH*, which uses tree search methods to find the optimal path to a goal. In PATH*, the search space is defined dynamically as a consequence of node testing. Maze-solving and the use of an associative data base for contextdependent node generation are also discussed. Execution of a plarined path is accomplished by a feedback guidance process with automatic error recovery.