30 May 2001Autonomous Agents1 The BOID architecture ( Conflicts Between Beliefs, Obligations, Intentions and Desires ) Jan Broersen Mehdi Dastani Joris Hulstijn Zisheng Huang Leendert van der Torre Department of Artificial Intelligence Vrije Universiteit Amsterdam

30 May 2001Autonomous Agents2 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

30 May 2001Autonomous Agents3 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  ))))

30 May 2001Autonomous Agents4 Interpreter (Reasoner) BDI Architecture PlansBeliefs Desires Intentions Sensor Effectors

30 May 2001Autonomous Agents5 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

30 May 2001Autonomous Agents6 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

30 May 2001Autonomous Agents7 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

30 May 2001Autonomous Agents8 BI-I- OD Obs. Act. Social Simple Minded  ( r b ) <  ( r i ) <  ( r o ) <  ( r d )

30 May 2001Autonomous Agents9 B I-I- O D Obs. Act. Super Selfish  ( r b ) <  ( r d ) <  ( r i )   ( r b ) <  ( r d ) <  ( r o )

30 May 2001Autonomous Agents10 B I-I- O D Obs.Act. P BOID Architecture

30 May 2001Autonomous Agents11  et  s   ch   et  s  ch  et  gc gc   s   ch Act. P Example : Initial State “ Simple-minded  ( r b ) <  ( r i ) < … ”  et = expensive ticket s = spend-much-money ch = cheap hotel gc = go conference

30 May 2001Autonomous Agents12  gc gc   s Act. P Example : Step 1 “ Simple-minded  ( r b ) <  ( r i ) < … ”  {et}   ch  et  s   ch   et  s  ch  et et = expensive ticket s = spend-much-money ch = cheap hotel gc = go conference

30 May 2001Autonomous Agents13  et  s   ch   et  s  ch  et gc   s Act. P Example : Step 2 “ Simple-minded  ( r b ) <  ( r i ) < … ”  {et} {et,gc}   ch  gc et = expensive ticket s = spend-much-money ch = cheap hotel gc = go conference

30 May 2001Autonomous Agents14  gc gc   s Act. P Example : Step 3 “ Social … <  ( r o ) <  ( r d ) ”  {et,gc}   ch {et,gc}  et  s   ch   et  s  ch  et et = expensive ticket s = spend-much-money ch = cheap hotel gc = go conference

30 May 2001Autonomous Agents15  et  s   ch   et  s  ch  et  gc Act. P Example : Step 4 “ Social … <  ( r o ) <  ( r d ) ”  {et,gc} {et,gc,  s}   ch gc   s et = expensive ticket s = spend-much-money ch = cheap hotel gc = go conference

30 May 2001Autonomous Agents16  gc gc   s Act. P Example : Step 5 “ Social … <  ( r o ) <  ( r d ) ”  {et,gc,  s}   ch {et,gc,  s,ch}  et  s   ch   et  s  ch  et et = expensive ticket s = spend-much-money ch = cheap hotel gc = go conference

30 May 2001Autonomous Agents17  et  s   ch   et  s  ch  et  gc gc   s Act. P Example : Step 6 “ Social … <  ( r o ) <  ( r d ) ”  {et,gc,  s,ch}   ch et = expensive ticket s = spend-much-money ch = cheap hotel gc = go conference

30 May 2001Autonomous Agents18  gc gc   s Act. P Example : Step 7 “ Social … <  ( r o ) <  ( r d ) ”    ch {et,gc,  s,ch}  et  s   ch   et  s  ch  et et = expensive ticket s = spend-much-money ch = cheap hotel gc = go conference

30 May 2001Autonomous Agents19  gc gc   s Act. P Example : Step 3 “Selfish … <  ( r d ) <  ( r o ) ”    ch {et,gc}  et  s   ch   et  s  ch  et et = expensive ticket s = spend-much-money ch = cheap hotel gc = go conference

30 May 2001Autonomous Agents20  et  s   ch   et  s  ch  et  gc gc   s Act. P Example : Step 4 “Selfish … <  ( r d ) <  ( r o ) ”  {et,gc,  ch} {et,gc}   ch et = expensive ticket s = spend-much-money ch = cheap hotel gc = go conference

30 May 2001Autonomous Agents21  et  s   ch   et  s  ch  et  gc gc   s Act. P Example : Step 5 “Selfish … <  ( r d ) <  ( r o ) ”  {et,gc,  ch}   ch et = expensive ticket s = spend-much-money ch = cheap hotel gc = go conference {et,gc,  ch}

30 May 2001Autonomous Agents22  et  s   ch   et  s  ch  et  gc gc   s Act. P Example : Step 5 “Selfish … <  ( r d ) <  ( r o ) ”    ch et = expensive ticket s = spend-much-money ch = cheap hotel gc = go conference {et,gc,  ch} {et,gc,  ch,  s}

30 May 2001Autonomous Agents23 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