Planning and Resource Allocation for Hard Real-Time, Fault-Tolerant Plan Execution

We describe the interface between a real-time resource allocation system with an AI planner in order to create fault-tolerant plans that are guaranteed to execute in hard real-time. The planner specifies the task set and all execution deadlines required to ensure system safety, then the resource utilization. A new interface module combines information from planning and resource allocation to enforce development of plans feasible for execution during a variety of internal system faults. Plans that over-utilize any system resource trigger feedback to the planner, which then searches for an alternate plan. A valid plan for each specified fault, including the nominal no-fault situation, is stored in a plan cache for subsequent real-time execution. We situate this work in the context of CIRCA, the Cooperative Intelligent Real-time Control Architecture, which focuses on developing and scheduling plans that make hard real-time safety guarantees, and provide an example of an autonomous aircraft agent to illustrate how our planner-resource allocation interface improves CIRCA performance.

[1]  R. James Firby,et al.  An Investigation into Reactive Planning in Complex Domains , 1987, AAAI.

[2]  Allen Newell,et al.  SOAR: An Architecture for General Intelligence , 1987, Artif. Intell..

[3]  David Lorge Parnas,et al.  Scheduling Processes with Release Times, Deadlines, Precedence, and Exclusion Relations , 1990, IEEE Trans. Software Eng..

[4]  Félix Ingrand,et al.  Managing Deliberation and Reasoning in Real-Time AI Systems , 1990 .

[5]  Leslie Pack Kaelbling,et al.  Planning With Deadlines in Stochastic Domains , 1993, AAAI.

[6]  Jia Xu,et al.  Multiprocessor Scheduling of Processes with Release Times, Deadlines, Precedence, and Exclusion Relations , 1993, IEEE Trans. Software Eng..

[7]  Matthew L. Ginsberg,et al.  Dynamic Backtracking , 1993, J. Artif. Intell. Res..

[8]  Victor R. Lesser,et al.  Design-to-time real-time scheduling , 1993, IEEE Trans. Syst. Man Cybern..

[9]  Craig Boutilier,et al.  Using Abstractions for Decision-Theoretic Planning with Time Constraints , 1994, AAAI.

[10]  Thomas Dean,et al.  Solving Time-critical Decision-making Problems with Predictable Computational Demands , 1994, AIPS.

[11]  David J. Musliner,et al.  Scheduling Issues Arising from Automated Real-Time System Design , 1995 .

[12]  John D. Lowrance,et al.  Planning and reacting in uncertain and dynamic environments , 1995, J. Exp. Theor. Artif. Intell..

[13]  David J. Musliner,et al.  World Modeling for the Dynamic Construction of Real-Time Control Plans , 1995, Artif. Intell..

[14]  Kang G. Shin,et al.  Optimal combined task and message scheduling in distributed real-time systems , 1995, Proceedings 16th IEEE Real-Time Systems Symposium.

[15]  Anees Shaikh,et al.  RTCAST: lightweight multicast for real-time process groups , 1996, Proceedings Real-Time Technology and Applications.

[16]  Edmund H. Durfee,et al.  Plan Development using Local Probabilistic Models , 1996, UAI.

[17]  Edmund H. Durfee,et al.  Expecting the Unexpected: Detecting and Reacting to Unplanned-for World States , 1996, AAAI/IAAI, Vol. 2.

[18]  Edmund H. Durfee,et al.  Development of Iterative Real-time Scheduler to Planner Feedback , 1997, IJCAI.

[19]  Edmund H. Durfee,et al.  Buying Time for Resource-Bounded Planning , 1997 .

[20]  Kang G. Shin,et al.  Assignment and Scheduling Communicating Periodic Tasks in Distributed Real-Time Systems , 1997, IEEE Trans. Software Eng..

[21]  P.D. Washabaugh,et al.  Solus: an autonomous aircraft for flight control and trajectory planning research , 1998, Proceedings of the 1998 American Control Conference. ACC (IEEE Cat. No.98CH36207).

[22]  Edmund H. Durfee,et al.  Plan generation and hard real -time execution with application to safe, autonomous flight , 1999 .

[23]  Kang G. Shin,et al.  Combined Task and Message Scheduling in Distributed Real-Time Systems , 1999, IEEE Trans. Parallel Distributed Syst..