1. Belief Desire Intention
Example Systems

2. BDI Mental model Organizes agency Folk Psychology
Belief - what the agent believes about the world
Desires - agent goals
Intensions - plans

3. A BDI model
BDI Model-based Crowd Simulation by Cho, Iketani, Kikuchi, Nishimura, Hayashi, and Hattori
Model of crowd response to a fire

4. A BDI model (cont.) Perceiver Executor Belief Desire Intention
Reasoner
Selector

5. Reasoner Rule based Rules use beliefs to define the desires
In Crowd simulation desires:
Take water
Pour water
Run away
Desires have weights - based on weights of beliefs

6. Selector Selects based on highest weight
Current intension weight has a multiplier applied - k
A new intension is chosen if:
Weightnew > Weigthcurrent * k
This prevents rapid changes

7. The Simulation Agent Infrastructure (SAI)
The Simulation Agent Infrastructure (SAI) .. By Ronnquist, Lucas, and Howden
Military Simulation in a Close Action Simulator

8. Uses JACK intelligent Agents
Uses Java base
Allows extensions via plug ins
Tactics defined as intensions
Uses events as communication
Agents interact as teams

9. BDI for Intelligent Agents in Computer Games by Davies ad Mehdi
Used Unreal Tournament via GameBots and JavaBots

10. Desires Goals Types (desires): Maintenance: Achieve Go to x Perform
Achieve, Maintenance and Perform
Maintenance:
Health over 50%
Achieve
Go to x
Perform
Explore

11. Intensions Simple actions: Complex actions Rotate, walk, shoot, etc.
Find path (returns list of nodes)

12. Summary