Matthew Walter

MIT CSAIL, Stata Center
32 Vassar Street, 32-335 (map)
Cambridge, MA 02139
USA

Tel: +1 (617) 253-7772
Fax: +1 (617) 253-4640
E-mail: mwalter "at" csail "dot" mit "dot" edu
PGP public key

News

• November 2014: I am now an assistant professor at the Toyota Technological Institute at Chicago.
• July 2014: Sudeep will present our articulation learning paper at RSS.
• May 2014: We will be publishing an article in IJRR on natural language understanding for semantic mapping.
• May 2014: A paper summarizing our work on the voice-commandable robotic forklift was accepted in JFR.
• April 2014: Our natural language-based semantic planning paper will appear at ISER 2014.
• April 2014: Business Insider has an article about our voice-commandable wheelchair.
• April 2014: An article in the Boston Globe discusses our voice-commandable wheelchair.
• March 2014: Our paper on mobile manipulation in unstructured environments was accepted for publication in JFR.
• March 2014: I will be giving a talk on learning semantics from natural language at WPI.
• March 2014: I am giving an invited talk in the Department of Computer Science at Cornell.
• February 2014: I am giving an invited talk in the Department of Computer Science at Rutgers.
• February 2014: Tom Howard and I released our h2sl natural language understanding code.
• February 2014: I am giving an invtited talk at the Toyota Technological Institute at Chicago.
• January 2014: Our paper on our recent semantic mapping work was accepted at ICRA.
• January 2014: I will be giving a lecture and lab session on natural language understanding at the 2014 RoCKIn Camp in Rome.
• December 2013: There is an article in the Boston Business Journal about our voice-commandable wheelchair.

Research Bio

I am a research scientist in the Computer Science and Artificial Intelligence Laboratory (CSAIL) at the Massachusetts Institute of Technology (MIT), working in collaboration with Seth Teller.

Robots will inspire human trust only if they prove able to work safely and predictably alongside people in our homes and our workplaces. My research focuses on advanced perception algorithms that endow robots with a rich awareness of their surroundings and the ability to interact safely and naturally with humans in unstructured environments. I am interested in algorithms that take as input multi-modal observations of a robot's surround (e.g., laser range data, image streams, and speech) and infer properties of the objects, places, people, and events that comprise a robot's environment, at a level of abstraction necessary to realize command and control mechanisms that are both intuitive and safe.

Curriculum Vitae: [pdf] [ps]

Brief Bio

I received my PhD from the Joint Program between MIT and the Woods Hole Oceanographic Institution (WHOI). My advisor was John Leonard.

My PhD research considered the problem of scaling robotic mapping and localization to larger unknown environments. I studied feature-based algorithms for simultaneous localization and mapping (SLAM) whereby a robot builds a map of the world while concurrently estimating its position in the map. My thesis work proposed a sparse information filter algorithm that is scalable and also preserves estimate consistency. The approach maintains a Gaussian probability distribution over the robot and map states, and takes advantage of insights into the natural structure of this model for SLAM. The Exactly Sparse Extended Information Filter (ESEIF) exploits a sparse parametrization of this distribution to reduce the computational and memory costs from quadratic to linear in the map's size. In addition to the gains in efficiency, a primary contribution of the algorithm is its ability to achieve sparsity in a principled, yet simple way that preserves consistency. For more information, please see my 2007 IJRR paper (pdf).

Publications

Pillai, S., Walter, M.R., and Teller, S., Learning Articulated Motions from Visual Demonstration. Proceedings of Robotics: Science and Systems, Berkeley, CA, July 2014.
[bibtex] [pdf]

Walter, M.R., Hemachandra, S., Homberg, B., Tellex, S., and Teller, S., A Framework for Learning Semantic Maps from Grounded Natural Language Descriptions. International Journal of Robotics Research (Special issue on RSS 2013), 2014 (accepted, to appear).
[bibtex] [pdf]

Walter, M.R., Antone, M., Chuangsuwanich, E., Correa, A., Davis, R., Fletcher, L., Frazzoli, E., Friedman, Y., Glass, J., How, J.P., Jeon, J.H., Karaman, S., Luders, B., Roy, N., Tellex, S., and Teller, S., A Situationally Aware Voice-Commandable Robotic Forklift Working Alongside People in Unstructured Outdoor Environments. Journal of Field Robotics, 2014 (accepted, to appear).
[bibtex] [pdf]

Duvallet, F., Walter, M.R., Howard, T., Hemachandra, S., Oh, J., Teller, S., Roy, N., and Stentz, A. Inferring Maps and Behaviors from Natural Language Instructions. Proceedings of the International Symposium on Experimental Robotics (ISER), Marrakech/Essaouira, June 2014.
[bibtex] [pdf]

Hemachandra, S., Walter, M.R., Tellex, S., and Teller, S., Learning Spatial-Semantic Representations from Natural Language Descriptions and Scene Classifications. Proceedings of the IEEE International Conference on Robotics and Automation (ICRA), Hong Kong, China, May 2014 (accepted, to appear).
[bibtex] [pdf]

Walter, M.R., Hemachandra, S., Homberg, B., Tellex, S., and Teller, S., Learning Semantic Maps from Natural Language Descriptions. Proceedings of Robotics: Science and Systems, Berlin, Germany, June 2013.
[bibtex] [pdf] [video]

Tellex, S., Thaker, P., Joseph, J., Walter, M.R., and Roy, N., Toward Learning Perceptually Grounded Word Meanings From Unaligned Parallel Data. Proceedings of the NAACL HLT Workshop on Semantic Interpretation in an Actionable Context, pp. 7-14, Montréal, Canada, June 2012.
[bibtex] [pdf]

Walter, M.R., Friedman, Y., Antone, M., and Teller, S., One-shot Visual Appearance Learning for Mobile Manipulation. International Journal of Robotics Research (Special Issue on Robot Vision), vol. 31, no. 4, pp. 554-567, April 2012.
[bibtex] [pdf]

Tellex, S., Kollar, T., Dickerson, S., Walter, M.R., Banerjee, A.G., Teller, S., and Roy, N., Approaching the Symbol Grounding Problem with Probabilistic Graphical Models. AI Magazine, vol. 32, num. 4, pp. 64-76, Winter 2011.
[bibtex] [pdf]

Perez, A., Karaman, S., Shkolnik, A., Frazzoli, E., Teller, S., and Walter, M.R., Asymptotically-optimal Path Planning for Manipulation using Incremental Sampling-based Algorithms. Proceedings of the IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), pp. 4307-4313, San Francisco, CA, September 2011.
[bibtex] [pdf] [software] [video] [MIT News, Slashdot, and ABC/Yahoo stories]

Tellex, S., Kollar, T., Dickerson, S., Walter, M.R., Banerjee, A.G., Teller, S., and Roy, N., Understanding Natural Language Commands for Robotic Navigation and Mobile Manipulation. Proceedings of the AAAI Conference on Artificial Intelligence, San Francisco, CA, August 2011.
[bibtex] [pdf]

Karaman, S., Walter, M.R., Perez, A., and Teller, S., Anytime Motion Planning Using the RRT*. Proceedings of the IEEE International Conference on Robotics and Automation (ICRA), pp. 1478-1483, Shanghai, China, May 2011.
[bibtex] [pdf] [presentation]

Walter, M.R., Friedman, Y., Antone. M., and Teller, S., Vision-based Reacquisition for Task-level Control. Proceedings of the International Symposium on Experimental Robotics (ISER), New Dehli, India, December 2010.
[bibtex] [pdf] [presentation]

Walter, M.R., Karaman, S., Frazzoli, E., and Teller, S., Closed-loop Pallet Engagement in Unstructured Environments. Proceedings of the IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), pp. 5119-5126, Taipei, Taiwan, October 2010.
[bibtex] [pdf] [video]

Walter, M.R., Friedman, Y., Antone, M., and Teller, S., Appearance-based Object Reacquisition for Mobile Manipulation. Proceedings of the IEEE Computer Vision and Pattern Recognition Workshops (CVPRW), San Francisco, California, June 2010.
[bibtex] [pdf] [presentation]

Karaman, S., Walter, M.R., Frazzoli, E., and Teller, S., Closed-loop Pallet Engagement in an Unstructured Environment. Proceedings of the IEEE International Conference on Robotics and Automation (ICRA) Workshop on Mobile Manipulation, Anchorage, Alaska, May 2010.
[bibtex] [pdf] [presentation]

Teller, S., Walter, M.R., Antone, M., Correa, A., Davis, R., Fletcher, L., Frazzoli, E., Glass, J., How, J.P., Huang, A.S., Jeon, J.H., Karaman, S., Luders, B., Roy, N., and Sainath, T., A Voice-Commandable Robotic Forklift Working Alongside Humans in Minimally-Prepared Outdoor Environments. Proceedings of the IEEE International Conference on Robotics and Automation (ICRA), pp. 526-533, Anchorage, Alaska, May 2010.
[bibtex] [pdf] [presentation]

Koch, O., Walter, M.R., Huang, A.S., and Teller, S., Ground Robot Navigation using Uncalibrated Cameras. Proceedings of the IEEE International Conference on Robotics and Automation (ICRA), pp. 2423-2430, Anchorage, Alaska, May 2010.
[bibtex] [pdf]

Correa, A., Walter, M.R., Fletcher, L., Glass, J., Teller, S., and Davis, R., Multimodal Interaction with an Autonomous Forklift. Proceedings of the ACM/IEEE International Conference on Human-Robot Interaction (HRI), pp. 243-250, Osaka, Japan, March 2010.
[bibtex] [pdf] [presentation]

Shkolnik, A., Walter, M., Tedrake, R., Reachability-Guided Sampling for Planning Under Differential Constraints. Proceedings of the IEEE International Conference on Robotics and Automation (ICRA), pp. 2859-2865, Kobe, Japan, May 2009.
[bibtex] [pdf]

Bahr, A., Walter. M.R., Leonard, J.J., Consistent Cooperative Localization. Proceedings of the IEEE International Conference on Robotics and Automation (ICRA), pp. 3415-3422, Kobe, Japan, May 2009.
[bibtex] [pdf]

Moore, D.C., Huang, A.S., Walter. M., Olson, E., Fletcher, L., Leonard, J., Teller, S., Simultaneous Local and Global State Estimation for Robotic Navigation. Proceedings of the IEEE International Conference on Robotics and Automation (ICRA), pp. 3794-3799, Kobe, Japan, May 2009.
[bibtex] [pdf]

Walter, M.R., Hover, F., and Leonard, J., SLAM for Ship Hull Inspection using Exactly Sparse Extended Information Filters. Proceedings of the IEEE International Conference on Robotics and Automation (ICRA), pp. 1463-1470, Pasadena, CA, May 2008.
[bibtex] [pdf]

Walter, M.R., Sparse Bayesian Information Filters for Localization and Mapping, PhD Thesis, Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution, February 2008.
[bibtex] [pdf]

Walter, M.R., Eustice, R.M., and Leonard, J.J., Exactly Sparse Extended Information Filters for Feature-based SLAM. International Journal of Robotics Research, vol. 26, num. 4, pp. 335-359, April 2007.
[bibtex] [pdf]

Eustice, R.M., Singh, H., Leonard, J.J., and Walter, M.R., Visually Mapping the RMS Titanic: Conservative Covariance Estimates for SLAM Information Filters. International Journal of Robotics Research, vol. 25, num. 12, pp. 1223-1242, December 2006.
[bibtex] [pdf]

Walter, M., Eustice, R., and Leonard, J., A Provably Consistent Method for Imposing Exact Sparsity in Feature-based SLAM Information Filters. In Proceedings of the International Symposium of Robotics Research (ISRR), San Francisco, CA, October 2005.
[bibtex] [pdf]

Eustice, R., Walter, M., and Leonard, J., Sparse Extended Information Filters: Insights into Sparsification. In Proceedings of the IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), pp. 641-648, Edmonton, Alberta, August 2005.
[bibtex] [pdf]

Eustice, R., Singh, H., Leonard, J., Walter, M., and Ballard, R., Visually Navigating the RMS Titanic with SLAM Information Filters. In Proceedings of Robotics: Science and Systems (RSS), Cambridge, MA, June 2005.
[bibtex] [pdf]

Olson, E., Walter, M., and Leonard, J., Single-Cluster Spectral Graph Partitioning for Robotics Applications. In Proceedings of Robotics: Science and Systems (RSS), Cambridge, MA, June 2005.
[bibtex] [pdf]

Walter, M., and Leonard, J., An Experimental Investigation of Cooperative SLAM. In Proceedings of the IFAC Symposium on Intelligent Autonomous Vehicles, Lisbon, Portugal, July 2004.
[bibtex] [pdf]