Dr Charles Gretton
Areas of expertise
- Artificial Intelligence And Image Processing 0801
- Decision Theory 220302
- Logic 220308
- Adaptive Agents And Intelligent Robotics 080101
Research interests
I am a computer scientist who works in a sub-field of Artificial Intelligence called Automated Planning. Although my interests extend to other subjects in Machine Learning and Automated Reasoning, my expertise lies mostly within planning. I study and develop AI technologies that enable machines to reason about deliberations in the world, and to reason about how to extend their knowledge about the world intelligently. Subjects where I have published works include: state-based heuristic planning with continuous time (TIL-Relaxed Heuristic), exploiting sub-problem symmetries -- 'descriptive quotient', computing plan-length upper bounds -- 'sublist diameter', mixed decision-theoretic and sequential planning for robot control acting in large, complex, real-world environments featuring task and observation objectives -- ''Switching", scalable and efficient representations of transition system models in SAT -- 'Precisely Split Representations', cost-optimal deterministic planning using Weighted MAXSAT -- 'COPLAN', stochastic local search (SLS) procedures for Boolean SAT(isfiability) -- 'gNovelty+', SLS for Vertex Cover -- 'COver Edges Ramdomly', decision-theoretic planning and (relational-)reinforcement learning with non-Markovian rewards -- various Linear Temporal Logics. I've also done published research on aesthetic criteria in solving vehicle routing problems, game-theoretic cost allocations in logistics, and explorations of connectionist machine learning for synthesising aspects of Australian rules football (AFL) games.
Industrial application areas I worked in include transportation of fast moving consumer goods, fleet and route optimisation, product stocking policies, pricing, and SKU recommendation.
Biography
Since 2018 I have been convening the much celebrated and loved TechLauncher program at the Australian National University. That program comprises 35 teams of students working collaboratively and professionally together to: (i) create and leverage technology innovations to build and scale new enterprises, or (ii) fulfil statements of work and build relationships with business, industry, and government organisations in the Canberra region and around the world. I also lead projects on scaling logical inference with commonwealth government organisations, actively contribute to projects in the aerospace and astronomy domains, and occasionally collaborate with artist to expose and celebrate the clockwork orange in fashionable machine learning paradigms. In mid 2015 I co-founded Red Analytics PTY LTD (a.k.a. HIVERY), a Data61 spinout supported by the coca-cola founders platform. I was a senior researcher with the Data61 (NICTA) lab in Canberra from August of 2011. Prior to that I was a research fellow with the Intelligent Robotics Lab at the University of Birmingham 2008-2011; There I worked on a project investigating cognitive robots that could self-understand and self-extend. I was a researcher with the NICTA lab in Brisbane 2006-2008; There, I worked on fundamental research in AI Search, and simulation studies of city wide evacuation planning. I have also held adjunct positions at Griffith University since 2006. I am the primary author of NRMDPP, runner up in the probabilistic track of the 2004 International Planning Competition. I am a co-author of gNovelty+, winner of the "Random" category at the 2007 International SAT competition.
Publications
- Allard, T, Gretton, C & Haslum, P 2018, 'A TIL-Relaxed Heuristic for Planning with Time Windows', 28th International Conference on Automated Planning and Scheduling (ICAPS 2018), ed. Mathijs de Weerdt, Sven Koenig, Gabriele Röger, Matthijs T. J. Spaan, AAAI Press, Delft, The Netherlands, pp. 2-10.
- Abdulaziz, M, Norrish, M & Gretton, C 2018, 'Formally Verified Algorithms for Upper-Bounding State Space Diameters', Journal of Automated Reasoning, vol. 61, no. 1, pp. 485-520.
- Hanheide, M, Gobelbecker, M, Horn, G et al 2017, 'Robot task planning and explanation in open and uncertain worlds', Artificial Intelligence, vol. 247, pp. 119-150pp..
- Abdulaziz, M, Gretton, C & Norrish, M 2017, 'A state-space acyclicity property for exponentially tighter plan length bounds', 27th International Conference on Automated Planning and Scheduling (ICAPS 2017), AAAI Press, AAAI Press, pp. 2-10.
- Aziz, H, Cahan, C, Gretton, C et al 2016, 'A Study of Proxies for Shapley Allocations of Transport Costs', Journal of Artificial Intelligence Research, vol. 56, no. -, pp. 573 - 611pp.
- Aziz, H, Cahan, C, Gretton, C et al 2015, 'A Study of Proxies for Shapley Allocations of Transport Costs', AAAI 1st Workshop on Artificial Intelligence for Transportation, WAIT 2015, AAAI Press, USA, pp. 2-10.
- Grzybowska, H, Gretton, C, Kilby, P et al 2015, 'Decision Support System for a Real-Time Field Service Engineer Scheduling Problem with Emergencies and Collaborations', Transportation Research Record, vol. 2497, no. 2497, pp. 117 - 123pp.
- Abdulaziz, M, Gretton, C & Norrish, M 2015, 'Mechanising Theoretical Upper Bounds in Planning', 24th International Conference on Automated Planning and Scheduling 2014 (ICAPS), ed. S Chien, A Fern, W Ruml, M Do, Association for the Advancement of Artificial Intelligence (AAAI), USA, pp. 1 - 7pp.
- Abdulaziz, M, Gretton, C & Norrish, M 2015, 'Verified over-approximation of the diameter of propositionally factored transition systems', 6th International Conference on Interactive Theorem Proving, ITP 2015, ed. Zhang X.Urban C., Springer International Publishing Switzerland, TBC, pp. 1-16.
- Abdulaziz, M, Norrish, M & Gretton, C 2015, 'Exploiting Symmetries by Planning for a Descriptive Quotient', International Joint Conference on Artificial Intelligence IJCAI 2015, ed. Qiang Yang, Michael Wooldridge, AAAI Press, Palo Alto, California, USA, pp. 1479-1486.
- Gretton, C 2014, 'A more expressive behavioral logic for decision-theoretic planning', Lecture Notes in Computer Science (LNCS), vol. 8862, pp. 13-25.
- Rintanen, J & Gretton, C 2013, 'Computing Upper Bounds on Lengths of Transition Sequences', 23rd International Joint Conference on Artificial Intelligence, IJCAI 2013, AAAI Press, USA, pp. 2365-2372.
- Gretton, C & Kilby, P 2013, 'A Study of Shape Penalties in Vehicle Routing', TRISTAN VIII 2013 - Eighth Triennial Symposium on Transportation Analysis, American Society of Transportation and Logistics, Chicago, USA, pp. 1-4pp.
- Hanheide, M, Gretton, C, Dearden, R et al 2011, 'Exploiting Probabilistic Knowledge under Uncertain Sensing for Efficient Robot Behaviour', International Joint Conference on Artificial Intelligence (IJCAI 2011), ed. Toby Walsh, AAAI Press, Menlo Park California, pp. 2442-2449pp.
- Gobelbecker, M, Gretton, C & Dearden, R 2011, 'A switching planner for combined task and observation planning', National Conference on Artificial Intelligence (AAAI 2011), ed. Wolfram Burgard, AAAI Press, pp. 964-970.
- Robinson, N, Gretton, C, Pham, D et al. 2010, 'Partial Weighted MaxSAT for Optimal Planning', 11th Pacific Rim International Conference on Artificial Intelligence, ed. Byoung-Tak Zhang and Mehmet A. Orgun, Springer, Daegu, Korea, pp. 231-243.
- Robinson, N, Gretton, C, Pham, D et al. 2010, 'Cost-optimal planning using weighted MaxSAT', Workshop on Constraint Satisfaction Techniques for Planning and Scheduling Problems, COPLAS 2010, Conference Organising Committee, Toronto, ON, pp. 14-22.
- Robinson, N, Gretton, C, Pham, D et al. 2010, 'Partial weighted MaxSAT for optimal planning', 11th Pacific Rim International Conference on Artificial Intelligence, PRICAI 2010, Springer Link, Berlin, pp. 231-243.
- Robinson, N, Gretton, C, Pham, D et al 2009, 'SAT-Based Parallel Planning Using a Split Representation of Actions', 19th International Conference on Automated Planning and Scheduling, ed. Alfonso Gerevini, Adele E. Howe, Amedeo Cesta, Ioannis Refanidis, AAAI Press, Thessaloniki, Greece.
- Pham, D, Thornton, J, Gretton, C et al 2008, 'Combining Adaptive and Dynamic Local Search for Satisfiability', Journal on Satisfiability, Boolean Modeling and Computation, vol. 4, no. 2-4, pp. 149--172.
- Robinson, N, Gretton, C, Pham, D et al 2008, 'A Compact and Efficient SAT Encoding for Planning', 18th International Conference on Automated Planning and Scheduling 2008 (ICAPS), ed. Jussi Rintanen, Bernhard Nebel, J. Christopher Beck, Eric A. Hansen, American Association for Artificial Intelligence (AAAI) Press, Sydney, pp. 296-303.
- Werner, F, Gretton, C, Maire, F et al 2018, 'Induction of Topological Environment Maps from Sequences of Visited Places', 2008 IEEE/RSJ International Conference on Intelligent Robots and Systems, IEEE, Nice, France, pp. 2890--2895.
- Thiebaux, S, Gretton, C, Slaney, J et al 2006, 'Decision-theoretic planning with non-Markovian rewards', Journal of Artificial Intelligence Research, vol. 25, pp. 17-74.
- Gretton, C & Thiebaux, S 2004, 'Exploiting first-order regression in inductive policy selection', Conference on Uncertainty in Artificial Intelligence (UAI 2004), ed. M. Chickering, J. Halpern, AUAI Press, Arlington, VA USA, pp. 217-225.
- Gretton, C, Price, D & Thiebaux, S 2003, 'Implementation and Comparison of Solution Methods for Decision Processes with Non-Markovian Rewards', Conference on Uncertainty in Artificial Intelligence (UAI 2003), ed. C. Meek, Morgan Kauffman Publishers, San Francisco, California, USA, pp. 289-296.
- Gretton, C, Price, D & Thiebaux, S 2003, 'NMRDPP: A System for Decision-theoretic Planning with Non-Markovian Rewards', International Workshop on Planning under Uncertainty and Incomplete Information, ed. Geffner, Pistore, Smith, Conference Organising Committee, Trento, Italy, pp. 48-56.