Planning and resource allocation for hard real-time, fault-tolerant plan execution

We describe the interface between a real-time resource allocation system wi th an AI planner in order to create fault-tolerant plans that are guarantee d to execute in hard real-time. The planner specifies the task set and all execution deadlines required to ensure system safety, then the resource uti lization. A new interface module combines information from planning and res ource allocation to enforce development of plans feasible for execution dur ing a variety of internal system faults. Plans that over-utilize any system resource trigger feedback to the planner, which then searches for an alter nate plan. A valid plan for each specified fault, including the nominal no- fault situation, is stored in a plan cache for subsequent rear-time executi on. We situate this work in the context of CIRCA, the Cooperative Intellige nt Real-time Control Architecture, which focuses on developing and scheduli ng plans that make hard real-time safety guarantees, and provide an example of an autonomous aircraft agent to illustrate how our planner-resource all ocation interface improves CIRCA performance.