Co-ordination and Co-operation Between CGF Agents

1. Co-ordination and Co-operation Between CGF Agents Dr Jeremy Baxter Parallel and Distributed Simulation Group S&P Sector, Malvern

2. Overview of Presentation • Background • Co-ordination and Co-operation problems • Techniques from Multi-Agent Systems • Joint Intentions theory. • Four step model • Example implementation • Squadron (Company) assault

3. Command and Control Squadron Intelligence Commander Troop Troop Troop Commander Commander Commander Background • “Broad Agents” based CGF system • Military command and control structure • Independent Agents and behaviours for each level • Breaks up responsibilities and behaviours Higher Level Objective Lower Level Objectives Tank Tank Tank

4. Initial Co-ordination Problems • Complex composite behaviours • Initial timing by message passing • Prone to programming bugs • Context lost if commander died • Weak model of group context • produced separately from orders to subordinates • developer responsible for linking group and sub-group states

5. Generic Problems and Solutions • Existing CGF systems have problems • Lack of co-operative group behaviour • Co-ordination is inflexible and prone to failure • Composite behaviours are therefore weak and brittle • Solutions from Multi Agent Systems literature • Provide a framework for group behaviour • Model the context for re-planning decisions • Model agents’ responsibilities to their group and the operator

6. Joint Intentions Theory • A logic based model of what it means to co-operate on a task • Explicitly represents roles and commitments • Improves robustness • Key elements • Mutual belief (I know he knows I know …..) • Mutual goals and plans • Commitment to informing other agents • Example:- Traffic convoys

7. Definitions • Weak GoalEITHER Goal to achieve P OR P has been achieved AND Goal to inform group P is achieved OR P is unachievable AND Goal to inform group P unachievable • Weak Mutual Goal Mutual belief that everyone has a Weak Goal to achieve P • Joint Persistent Goal Mutual belief that P has not yet been achieved AND Mutual goal to achieve P AND UNTIL Mutual belief that P is achieved, unachievable or irrelevant A Weak Mutual Goal to achieve P will persist

8. Definitions 2 • Joint IntentionTo have a Joint Persistent Goal to do an action while mutually believing that all involved are doing the action • A ‘Group State’committing all involved both to the goal, a to a way of achieving it and conventions on how to deal with problems • Key elements • Establishing mutual belief in an action • Commitment to informing others

9. Using Joint Intentions • Attack Helicopter CGF (Tambe et al in STOW) • Preventing teamwork failures, e.g. loss of Scout Helicopter • Co-ordinating independently designed behaviours • generic support for composite actions • Further Issues • Need to establish approximation to mutual belief • Ways of establishing team goals, e.g. roles and capabilities • Building up and representing shared goals and plans

10. Four Step Model • Recognition • Team Formation • Identifying a group capable of performing the task • Plan Formation • Forming and agreeing on the steps to take. Identifying co-ordination • Team Action • Forming individual, co-ordinated, plans and failure recovery

11. Example Composite Behaviour • Tank Squadron Assault Involves: • Finding a Fire Support Position to Pin down the Enemy • Finding a Concealed Approach for the Assault Group Cover Break Point Assault Group Form Up Point Fire Support Axis Assault Approach Fire Support Form Up Point Enemy Position Fire Support Position 9 Squadron Current Position

12. Example Implementation • Explicit Group plans • Templated plans with roles • Clear co-ordination statements • Shared Group state • Used for co-ordination and recovery if commander dies • Individual plans derived from group template • Assigned based on roles and capabilities

13. A Composite Assault Behaviour

14. Summary • Co-ordination and co-operation is an important aspect of CGF systems • Without good representations co-ordination becomes hidden and prone to failures • Composite, composable behaviours will need reliable, generic co-ordination and co-operation techniques • Formal techniques from Multi Agent Systems research can help

15. Further Work • Adjusting the theory to align with military practice • General solutions to execution problems • e.g. role replacement • Operator involvement • visualisation of co-ordination • commitments to the operator by CGF agents