Interprocess communication and task sequencing is performed by the Task Control Architecture (TCA). TCA is a general-purpose architecture for mobile robots that provides support for distributed communication via sockets, task decomposition and scheduling, resource management, execution monitoring, and error recovery [Simmons 1994a]. TCA-based systems consist of a number of distributed, concurrent processes that communicate via coarse-grained message passing. TCA connects processes, routes messages, and coordinates overall control and data flow. It also provides capabilities to log and analyze message traffic, which has proven to be very useful in understanding certain critical timing issues in the autonomous navigation system. Its code is publicly available.

LRD Navigation Group - (last updated in March 1995)
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