1. SRI International MPA for the SUO Planning and Decision Aid David E. Wilkins SRI International Artificial Intelligence Center email: wilkins@ai.sri.com URL: http://www.ai.sri.com/~wilkins June 1999

2. SRI International Long-term Contributions of PDA to the Soldier Shared plan representations cognizant of miltary principles, doctrine, SOPs and TTPs. Makes possible: Doctrinally correct plan usable by everyone. Fast generation of multiple distinct COAs, including ones the commander may not have considered. Support commander creativity through human guidance. Uniformly high plan quality, even during high-stress crises. Continuous analysis of the plan using multiple metrics. Monitor plan execution and respond quickly to events, helping the commander modify the plan appropriately. Provide relevant information to other echelons, allowing fast communication while preserving bandwidth

3. SRI International Multiagent Planning Architecture (MPA) Agent-based framework (efficiency and modularity) Enable interoperation of diverse planning technologies –plan generation, scheduling, temporal reasoning, evaluation,... Provide a shared plan representation Provide organizational structure, control strategies, and communication protocols, wrappers Develop planning and metaplanning agents specifically for collaborative planning and scheduling Support dynamic, event-driven reconfiguration of planning organization and strategies at runtime

4. SRI International MPA Components Planning Cells - organizational units for agents: –Planning Agent (PA), Meta Planning Agent (Meta-PA) –Planning-Cell Managers Shared plan model and representation –based on extenstions to Act formalism Communication Protocols Transport Level: robust, reuse existing technology Content Level: high-level performatives Plan Server - central repository for plans and related information Process Management - extensible set of reactive control policies for implementing problem-solving strategies Support- documentation of each agent’s I/O, Wrappers for individual technologies

5. SRI International Communication Messages use KQML-like performatives : –communication performatives –plan performatives MPA wrappers and libraries for : –message passing –multithreaded processing –tracing and logging of messages Communication substrates: –KQML (Lockheed-Martin and UMBC) –ILU (Xerox PARC) –OAA (SRI International)

6. SRI International Examples of MPA messages Requesting solutions from the meta-PCM: (:evaluate :content (:multiple-solve :task “air-superiority” :advice-contexts ((“yuma” (:ingress-at-yuma :deny-air-picture)) (“yuma-sf” (:ingress-at-yuma :ingress-2-at-san-francisco :breach-at-two-places))))) Retrieving the plan from the plan server: (:ask-all :content (:query-plan :task “air-superiority” :plan “plan-yuma-sf” :view :ascii)

7. SRI International MPA Plan Server Central repository for planning information Hierarchical model of plans ( plans, tasks, and action networks) Answers queries about the plan, providing multiple views Supports a broad range of plan management capabilities Annotations - declarations of high-level attributes of plans, planning process Product Annotation: pedigree, flaws, plan quality, resource status Process Annotation: time spent on plan components, current status Triggers - rules used to notify cell agents of planning events Example: trigger notifies PCM of overutilized resource annotation, PCM reacts by changing planning strategy

8. SRI International MPA Applied to ACP Validate MPA by integrating several systems in DARPA Planning Initiative (TIE 97-1): INSPECT (ISI) OPIS (CMU) Advisable Planner (SRI) SIPE-2 (SRI) ACS (UMass) Process Panel (AIAI -UEdin) APAT (ISX) VISAGE (MAYA) Domain is Air Campaign Planning –thousands of objects, several thousand nodes in each plan –plan down to support mission level (must allocate supporting resources) –air superiority objective only –targets grouped into networks which depend on other networks –network effectiveness is modeled quantitatively

9. SRI International TIE 97-1 Architecture Annotations Triggers Plan Server Cue: (TEST (ready unit1)) ACT2 Cue: Answer query ACT1 APAT GUI Plan Viewer MPA Planning AgentsMPA Agent Evaluation Toolkit ACSVISAGE Advisable Planner (SIPE-2) Planner (SIPE-2) Scheduler (OPIS) Planning-Cell Manager (PRS) Inspect Process Monitor Meta Planning-Cell Manager (PRS)

10. SRI International TIE 97-1Demonstrations Sept 98 - EFX 98, Ft. Walton Beach FL May 98 - ARPI Workshop, Monterey CA Feb 98 - DARPA, Arlington VA Dec 97 - JFACC PMR, San Pedro CA Nov 97 - ARPI Workshop, San Francisco CA Increasing Capabilities DARPA

11. SIPE-2 PA GUI/Advice Manager (AP and PRS) Create a plan Meta-PA Planning-Cell Manager (PRS) Planning-Cell Designator Plan Complete Request: Plan ok? PA Scheduler (OPIS) PA Temporal Reasoner (OPIS) PA Temporal Reasoner (Tachyon) or PA (meta-PA) Critic Manager all (SIPE-2) PA (meta-PA) Search Manager one-level (SIPE-2) PA Schedule Critic (new) PA Temporal Constraint Critic (SIPE-2) OPIS Request Expand Next Level Agent KQML Message Cue: (TEST (ready unit1)) ACT2 Cue : Plan One-Level ACT1 Cue: (TEST (ready unit1)) ACT2 Cue : Resource Critic ACT1 Annotations Triggers Plan Server (PRS) Cue: (TEST (ready unit1)) ACT2 Cue: Answer query ACT1 Plan Complete Create a plan SRI International Inside an MPA Planning Cell

12. Create a plan Cell Manager (CPEF) Cell Designator Higher Echelon: Plan Complete Request: Modify plan Platoon A PDA Planner (SIPE-2, O-Plan) Terrain Reasoner Fire Control Planner (e.g.) Agent KQML Message Cue: (TEST (ready unit1)) ACT2 Cue : Plan One-Level ACT1 Cue: (TEST (ready unit1)) ACT2 Cue : Resource Critic ACT1 Annotations Triggers Plan Server (PRS) Cue: (TEST (ready unit1)) ACT2 Cue: Answer query ACT1 Plan Complete New Op Order SRI International Company Commander MPA PDA Cell Platoon B PDA Platoon C PDA At WTA

13. Agent KQML Message SRI International PDA Cell Higher Echelon Cell Manager (CPEF) New Order Possibly Shared Agents PlannerSubordinate PDA Cell Manager PlannerCell Manager Cue: (TEST (ready unit1)) ACT2 Cue : Plan One-Level ACT1 Visualization/Comparison Logistics Terrain Reasoner Multiple PDA Cell Configuration New Order Plan Subordinate PDA Plan Server

14. SRI International Opportunities Enabled by MPA Facilitate collaboration: –agents exchange information and influence each other during planning –can easily explore different degrees of collaboration Can more easily explore/evaluate: –different organizational units for flexible control policies –different planning styles and strategies –new or alternative technologies

15. SRI International Backup Slides

16. SRI International Support rapid, accurate military decision making in information-rich warfighting environment The Problem

17. SRI International Example MPA Performatives :annotation Insert Delete Ask-All Ask-One :trigger Insert Delete Ask-All Ask-One :update-task Tell Delete :update-plan Tell Delete :query-task Ask-all Ask-One :query-plan Ask-All Ask-One :query-node Ask-All Ask-One :ping Evaluate :pcd Tell Plan Performative Communication Performative Performatives accepted by the Plan Server

18. SRI International Planning Cells Hierarchically organized collection of planning agents Composed dynamially by the Planning-Cell Manager Planning Cell Designator (PCD) provides registry of agents to fill various roles: Planner: SIPE-2 Scheduler: OPIS Distribute tasks and PCD to PAs and meta-PAs Each cell includes a plan server PA meta-PA PA Plan Servermeta-PA PA Planning-Cell Manager Planning cell:

19. SRI International Planning Cell Manager (PCM) Persistent agent continuously accepting tasks Oversees problem-solving within a Planning Cell Provides a range of problem-solving behaviors and strategies –user-configurable –can adapts strategies in response to runtime activities PRS-based PCM –PCD and process state encoded in PRS database –strategies encoded in Acts –Example strategy: expand and critique by levels implemented by 14 Acts –small library of different PCMs various cell configurations, problem-solving strategies

20. SRI International Meta Planning-Cells Planning cell composed of a set of planning cells A Meta-PCM controls and coordinates the cells Accepts multiple planning requests, including advice Distributes tasks to available planning cells Gathers results for possible comparison Meta Planning-Cell: Planning Cell Meta Planning-Cell Manager Planning Cell

21. SRI International Act Plan Server PRS-based Plan Server in current MPA applications –builds on reactive control capabilities grounded in the Act Formalism model for plans Task: problem to be solved, advice, assumptions Action Networks: partial orders of activities, at multiple abstraction levels Plan: linked sets of action networks Nodes: individual activites (goals, actions) limited persistence, versioning, browsing, and no access control

22. Agent KQML Message Annotations Triggers Plan Server Cue: (TEST (ready unit1)) ACT2 Cue: Answer query ACT1 SRI International Planning Cell Meta Planning- Cell Manager (PRS) task solved request solution to task request solution to task Shared Agents Search Manager Critic Manager Planning-Cell Manager Shared Agents Search Manager Critic Manager Planning-Cell Manager Cue: (TEST (ready unit1)) ACT2 Cue : Plan One-Level ACT1 Visualization/Comparison Scheduler Simulator Temporal Reasoner MPA Multiple Planning-Cell Configuration