Project: A Declarative Planning System Based on Logic Programming
supported by the Austrian Science Funds
(FWF) under project number
P14781)
Students:
- Manuela Citrigno
- Chiara Cumbo
- Tina Dell'Armi
- Giuseppe Ielpa
- Jürgen Oberhofer
- Simona Perri
Planning and reasoning about actions and change are relevant
fields of AI reseach since its beginnings.
Declarative approaches to planning have been recently proposed in the
literature. In these approaches, the user specifies the planning
problem in a logic-based declarative formalism. Finding the desired plans
is then reduced to elementary problems in computational logic such as
satisfiability checking, which are solved by an efficient computational
engine. The main goal of this project is to advance this line of research,
and to build a declarative planning system which overcomes some
shortcomings of current approaches to declarative planning.
In particular, the computation of plans which are optimal
according to criteria such as costs of actions or desirability of
states should be supported, and computing such plans should be possible
also in scenarios where the knowledge about the planning world is incomplete.
The overall goal of this project is to build a declarative planning
system which overcomes drawbacks and shortcomings of existing systems
and can be profitably exploited for real life applications.
We expect to develop a system which can be used for solving planning
problems of reasonable size (non-toy examples, but not huge problem
instances). The user should benefit from quick prototyping of
applications.
This main goal can be split
into the following subgoals:
- Language Definition
- System Design and Implementation
- Formulation and Testing of Applications
In the course of the project we have developed the declarative logical
planning language \K, turning our special attention to domain-independence,
full declarativity, modularity, ease of maintenance, advanced capabilities
such as dealing with incomplete knowledge or formalzation of action costs,
and reducibility to Disjunctive Logic Programming (DLP).
To this end, we have analyzed existing approaches of declarative action and
planning languages and enriched them with new desirable features.
The current version of our language allows to encode incomplete knowledge
elegantly and in a straightforward way, enabling the user to express default
assumptions, nondeterministic action effects and incomplete initial knowledge.
We allow for parallel and sequential actions as well as optimistic
and conformant (secure) planning. Furthermore, the language allows to assign
possibly dynamic (i.e. time-dependent) costs to actions, formalizing
optimizition with respect to this costs which can be done by our
implementation:
Our research results have been incorporated in the prototype
version of the
DLVK system
,
a declarative planning system based on logic programming. The prototype
has been implemented on top of the underlying
DLV system
,
a powerful engine evaluating logic programs under the Answer Set Semantics.
Details and various examples on the usability of our system
to formalize and solve intricate planning tasks can be found on the
system homepage.
Further goals to be adressed include optimizing the currrent
transformation, to increase the system performance as well as
further language extensions such as including resource handling.
- [DEF+03]
- Jürgen Dix, Thomas Eiter, Michael
Fink, Axel Polleres, and Yingqian Zhang.
Monitoring agents using planning.
To appear in Proc. of the German Conference on Artificial Intelligence
(KI2003), 2003.
- [EFL+03a]
- Thomas Eiter, Wolfgang Faber,
Nicola Leone, Gerald Pfeifer, and Axel Polleres.
A Logic Programming Approach to Knowledge-State Planning, II: the
DLV K System.
Artificial Intelligence, 144(1-2):157-211, March 2003.
- [EFL+03b]
- Thomas Eiter, Wolfgang Faber,
Nicola Leone, Gerald Pfeifer, and Axel Polleres.
A Logic Programming Approach to Knowledge-State Planning: Semantics and
Complexity.
ACM Transactions on Computational Logic, 2003.
To appear.
- [EFL+03c]
- Thomas Eiter, Wolfgang
Faber, Nicola Leone, Gerald Pfeifer, and Axel Polleres.
Answer Set Planning under Action Costs.
Journal of Artificial Intelligence Research, 19:25-71, 2003.
- [EFLP03]
- Thomas Eiter, Wolfgang Faber,
Nicola Leone, and Gerald Pfeifer.
Computing Preferred Answer Sets by Meta-Interpretation in Answer Set
Programming.
Journal of the Theory and Practice of Logic Programming,
3:463-498, July/September 2003.
- [EP03]
- Thomas Eiter and Axel Polleres.
Transforming coNP checks to answer set computation by meta-interpretation.
In Proceedings of the 2003 Joint Conference on Declarative Programming
APPIA-GULP-PRODE 2003, Reggio Calabria, Italy, September 2003.
- [Pol03]
- Axel Polleres.
The declarative planning system DLVK: Progress and extensions.
In Jeremy Frank and Susanne Biundo, editors, Printed Notes of the
ICAPS-03 Doctoral Consortium, pages 94-98, June 2003.
- [CFLP02]
- Francesco Calimeri, Wolfgang
Faber, Nicola Leone, and Gerald Pfeifer.
Pruning Operators for Answer Set Programming Systems.
In Proceedings of the 9th International Workshop on Non-Monotonic
Reasoning (NMR'2002), pages 200-209, April 2002.
(PostScript)
- [EFL+02a]
- Thomas Eiter, Wolfgang Faber,
Nicola Leone, Gerald Pfeifer, and Axel Polleres.
Answer Set Planning under Action Costs.
In Sergio Flesca, Sergio Greco, Giovambattista Ianni, and Nicola Leone,
editors, Proceedings of the 8th European Conference on Artificial
Intelligence (JELIA), number 2424 in Lecture Notes in Computer
Science, pages 186-197, September 2002.
- [EFL+02b]
- Thomas Eiter, Wolfgang
Faber, Nicola Leone, Gerald Pfeifer, and Axel Polleres.
Answer Set Planning under Action Costs.
Technical Report INFSYS RR-1843-02-13, Institut für Informationssysteme,
Technische Universität Wien, October 2002.
Accepted for publication in Journal of Artificial Intelligence Research.
(PostScript)
- [EFL+02c]
- Thomas Eiter, Wolfgang Faber,
Nicola Leone, Gerald Pfeifer, and Axel Polleres.
The DLV K Planning System: Progress Report.
In Sergio Flesca, Sergio Greco, Giovambattista Ianni, and Nicola Leone,
editors, Proceedings of the 8th European Conference on Artificial
Intelligence (JELIA), number 2424 in Lecture Notes in Computer
Science, pages 541-544, September 2002.
(System Description).
- [Fab02]
- Wolfgang Faber.
Enhancing Efficiency and Expressiveness in Answer Set Programming
Systems.
PhD thesis, Institut für Informationssysteme, Technische Universität
Wien, 2002.
- [LPF+02a]
- Nicola Leone, Gerald Pfeifer,
Wolfgang Faber, Francesco Calimeri, Tina Dell'Armi, Thomas Eiter, Georg
Gottlob, Giovambattista Ianni, Giuseppe Ielpa, Christoph Koch, Simona Perri,
and Axel Polleres.
The DLV System.
In Sergio Flesca, Sergio Greco, Giovambattista Ianni, and Nicola Leone,
editors, Proceedings of the 8th European Conference on Artificial
Intelligence (JELIA), number 2424 in Lecture Notes in Computer
Science, pages 537-540, September 2002.
(System Description).
- [LPF+02b]
- Nicola Leone, Gerald Pfeifer,
Wolfgang Faber, Thomas Eiter, Georg Gottlob, Christoph Koch, Cristinel
Mateis, Simona Perri, and Francesco Scarcello.
The DLV System for Knowledge Representation and Reasoning.
Technical Report cs.AI/0211004, arXiv.org, November 2002.
Submitted to ACM TOCL.
(PostScript)
- [Pol02a]
- Axel Polleres.
Answer Set Planning with DLVK.
The PLANET Newsletter, 5:36-37, 2002.
(PDF)
- [Pol02b]
- Axel Polleres.
Answer Set Planning with DLVK: Planning with Action Costs, September 2002.
Poster presented at the PLANET'02 International Summer School on AI Planning
2002.
(PDF)
- [CFL+01]
- Francesco Calimeri, Wolfgang Faber,
Nicola Leone, Simona Perri, and Gerald Pfeifer.
DLV - Declarative Problem Solving using Answer Set Programming.
In Proceedings of the Seventh Congress of the Italian Association for
Artificial Intelligence AI*IA 2001, Bari, Italy, 2001.
- [EFL+01a]
- Thomas Eiter, Wolfgang Faber,
Nicola Leone, Gerald Pfeifer, and Axel Polleres.
A Logic Programming Approach to Knowledge-State Planning, II: the
DLV K System.
Technical Report INFSYS RR-1843-01-12, Institut für Informationssysteme,
Technische Universität Wien, December 2001.
To appear in Artificial Intelligence.
(PostScript)
- [EFL+01b]
- Thomas Eiter, Wolfgang Faber,
Nicola Leone, Gerald Pfeifer, and Axel Polleres.
A Logic Programming Approach to Knowledge-State Planning: Semantics and
Complexity.
Technical Report INFSYS RR-1843-01-11, Institut für Informationssysteme,
Technische Universität Wien, December 2001.
To appear in ACM Transactions on Computational Logic.
(PostScript)
- [EFL+01c]
- Thomas Eiter, Wolfgang Faber,
Nicola Leone, Gerald Pfeifer, and Axel Polleres.
System Description: The DLV K Planning System.
In Thomas Eiter, Wolfgang Faber, and Miroslaw Truszczynski, editors,
Logic Programming and Nonmonotonic Reasoning --- 6th International
Conference, LPNMR'01, Vienna, Austria, September 2001, Proceedings,
number 2173 in Lecture Notes in AI (LNAI), pages 413-416. Springer Verlag,
September 2001.
(PostScript)
- [EFL+01d]
- Thomas Eiter, Wolfgang Faber,
Nicola Leone, Gerald Pfeifer, and Axel Polleres.
The DLV K Planning System.
In Alessandro Cimatti, Héctor Geffner, Enrico Giunchiglia, and Jussi
Rintanen, editors, IJCAI-01 Workshop on Planning under Uncertainty and
Incomplete Information, pages 76-81, August 2001.
- [FLP01a]
- Wolfgang Faber, Nicola Leone, and
Gerald Pfeifer.
A Comparison of Heuristics for Answer Set Programming.
In Proceedings of the 5th Dutch-German Workshop on Nonmonotonic
Reasoning Techniques and their Applications (DGNMR 2001), pages
64-75, April 2001.
- [FLP01b]
- Wolfgang Faber, Nicola Leone, and
Gerald Pfeifer.
Experimenting with Heuristics for Answer Set Programming.
In Proceedings of the Seventeenth International Joint Conference on
Artificial Intelligence (IJCAI) 2001, pages 635-640, Seattle, WA,
USA, August 2001. Morgan Kaufmann Publishers.
(PostScript)
- [FLP01c]
- Wolfgang Faber, Nicola Leone, and
Gerald Pfeifer.
Optimizing the Computation of Heuristics for Answer Set Programming Systems.
In Thomas Eiter, Wolfgang Faber, and Miroslaw Truszczynski, editors,
Logic Programming and Nonmonotonic Reasoning --- 6th International
Conference, LPNMR'01, Vienna, Austria, September 2001, Proceedings,
number 2173 in Lecture Notes in AI (LNAI), pages 288-301. Springer Verlag,
September 2001.