Autonomous task control for mobile robots

The design and implementation of the task control architecture (TCA), a general-purpose framework plus facilities for building and controlling mobile robots, are presented. TCA is designed to support capabilities needed by many autonomous mobile robot systems, including concurrent planning, execution, and perception; reacting to changes in the environment; error recovery; and handling multiple tasks. The facilities that TCA provides for implementing these capabilities, including distributed processing, explicit representation and manipulation of hierarchical plans, concurrent monitoring of selected conditions, and context-dependent exception handling, are described, along with a mobile manipulator that uses the architecture to operate with multiple goals in a dynamic and uncertain environment. TCA has been implemented and is used to run several mobile robot testbeds