30 may 2001autonomous agents1 the boid architecture ( conflicts between beliefs, obligations,...

30 May 2001 Autonomous Agents 1

The BOID architecture( Conflicts Between Beliefs, Obligations,

Intentions and Desires )

Jan BroersenMehdi DastaniJoris Hulstijn

Zisheng HuangLeendert van der Torre

Department of Artificial IntelligenceVrije Universiteit Amsterdam


Layout of this Talk

• logics and architecture for autonomous agents• conflicts and agent types• BOID

– norms: Dignum et al, Castelfranchi, ...

– specialized architectures

– generic architecture

– example


BDI Logics• rational balance between its informational and

motivational attitudes

• axiomatization for each attitude– KD45 for beliefs; D and K for desires and intentions;

Necessitation for beliefs, desires, and intentions

• axiomatization between attitudes– static: Bp->Ip – dynamic: commitment strategies

A(Intend(a , A) U(Bel(a, ) Bel(a , E))))


Interpreter (Reasoner)

BDI Architecture

PlansBeliefs

Desires Intentions

Sensor

Effectors


BDP logic and architecture

• Reiter’s default logic: beliefs and desires are B and D defaults

• inconsistent beliefs or desires are possible: {T:-p/p , T:-p/p} leads to multiple extensions

• prioritization of defaults express agent types


Conflicts

• Simple conflicts, e.g. between two desires• Complex conflicts, e.g.:

– you believe that there are no cheap rooms close to the conference

– you are obliged to take cheap room– you desire to stay close to the conference– you intend to go to a conference

• Increasing # of possible conflicts in BOID


Conflicts and Agent Types

• Realistic agent: beliefs override others

• Social agent: obligations override desires

• Selfish agent: desires override obligations

• simple-minded agent: intentions override obligations and desires

• open-minded agent: desires and obligations override intentions


B I- O DObs.

Act.

Social Simple Minded

( rb ) < ( ri ) < ( ro ) < ( rd )


BI

-

ODObs. Act.

Super Selfish

( rb ) < ( rd ) < ( ri )

( rb ) < ( rd ) < ( ro )


B

I-

O

D

Obs. Act.P

BOID Architecture


et

s ch et

s ch et gc

gc s

ch

Act.P

Example : Initial State“ Simple-minded ( rb ) < ( ri ) < … ”

et = expensive tickets = spend-much-money

ch = cheap hotelgc = go conference


gc

gc sAct.

P

Example : Step 1“ Simple-minded ( rb ) < ( ri ) < … ”

{et}

ch

et

s ch et

s ch et




et

s ch et

s ch et

gc sAct.

P

Example : Step 2“ Simple-minded ( rb ) < ( ri ) < … ”

{et}

{et,gc}

ch

gc




gc

gc sAct.

P

Example : Step 3 “ Social … < ( ro ) < ( rd ) ”

{et,gc}

ch

{et,gc} et

s ch et

s ch et




et

s ch et

s ch et gc

Act.P

Example : Step 4“ Social … < ( ro ) < ( rd ) ”

{et,gc}

{et,gc,s}

ch

gc s




gc

gc sAct.

P


{et,gc,s}

ch {et,gc,s,ch}

et

s ch et

s ch et




et

s ch et

s ch et gc

gc sAct.

P


{et,gc,s,ch}{et,gc,s,ch} ch




gc

gc sAct.

P


ch {et,gc,s,ch}

{et,gc,s,ch} et

s ch et

s ch et




gc

gc sAct.

P

Example : Step 3“Selfish … < ( rd ) < ( ro ) ”

ch {et,gc} {et,gc}

et

s ch et

s ch et




et

s ch et

s ch et gc

gc sAct.

P


{et,gc,ch}{et,gc} ch




et

s ch et

s ch et gc

gc sAct.

P


{et,gc,ch} ch



{et,gc,ch}


et

s ch et

s ch et gc

gc sAct.

P


ch



{et,gc,ch}

{et,gc,ch, s}


Conclusion

• conflicts within or among informational and motivational attitudes

• conflict resolution and agent types

• small gap between logic and architecture

• extension selection: planning and scheduling

30 may 2001autonomous agents1 the boid architecture ( conflicts between beliefs, obligations,...

Documents