Publications

2026

Robots That Know What to Ask: Recovering Misaligned Rewards through Targeted Explanations
Robotics: Science and Systems (RSS), 2026conference
Helena Merker, Nick Walker and Andreea Bobu

@inproceedings{merker2026,
  author = {Merker, Helena and Walker, Nick and Bobu, Andreea},
  title = {Robots That Know What to Ask: Recovering Misaligned Rewards through Targeted Explanations},
  year = {2026},
  month = jul,
  location = {Sydney, Australia},
  booktitle = {Robotics: Science and Systems},
}

2025

Towards Personalizing Shared Autonomy with Human-in-the-Loop Robot Programs
CoRL 2025 Workshop on Human-to-Robot (H2R), 2025workshop
Daphne Chen, Sahitha Vuddagiri, Claire Yang, Nick Walker and Maya Cakmak

@inproceedings{chen2025towards,
  author = {Chen, Daphne and Vuddagiri, Sahitha and Yang, Claire and Walker, Nick and Cakmak, Maya},
  title = {Towards Personalizing Shared Autonomy with Human-in-the-Loop Robot Programs},
  year = {2025},
  month = sep,
  booktitle = {CoRL 2025 Workshop on Human-to-Robot},
}

Making Robot Behaviors Automatically Transparent
Doctoral dissertation, 2025thesis
Nick Walker

@phdthesis{walker2025dissertation,
  author = {Walker, Nick},
  title = {Making Robot Behaviors Automatically Transparent},
  school = {The University of Washington},
  year = {2025},
  month = mar,
  address = {Seattle, WA},
  pages = {166},
  isbn = {9798310397248},
  wwwpdf = {https://files.nickwalker.us/dissertation.pdf},
}

2024

I Can Tell What I Am Doing: Toward Real-World Natural Language Grounding of Robot Experiences
The 8th Conference on Robot Learning (CoRL), 2024conference
Zihan Wang, Brian Liang, Varad Dhat, Zander Brumbaugh, Nick Walker, Ranjay Krishna and Maya Cakmak

@inproceedings{wang2024doing,
  author = {Wang, Zihan and Liang, Brian and Dhat, Varad and Brumbaugh, Zander and Walker, Nick and Krishna, Ranjay and Cakmak, Maya},
  title = {I Can Tell What I Am Doing: Toward Real-World Natural Language Grounding of Robot Experiences},
  location = {Munich, Germany},
  pages = {1863--1890},
  editor = {Agrawal, Pulkit and Kroemer, Oliver and Burgard, Wolfram},
  volume = {270},
  series = {Proceedings of Machine Learning Research},
  year = {2024},
  month = nov,
  publisher = {PMLR},
  booktitle = {Proceedings of The 8th Conference on Robot Learning},
  wwwpdf = {https://raw.githubusercontent.com/mlresearch/v270/main/assets/wang25g/wang25g.pdf},
  wwwurl = {https://sites.google.com/view/real-world-robot-narration/home}
}

Can Large Language Models Help Developers with Robotic Finite State Machine Modification?
LangRob Workshop at Conference on Robot Learning (CoRL), 2024workshop
Xiangyu Gan*, Yuxin Ray Song*, Nick Walker and Maya Cakmak

@article{gan2024can,
  author = {Gan, Xiangyu and Song, Yuxin Ray and Walker, Nick and Cakmak, Maya},
  title = {Can Large Language Models Help Developers with Robotic Finite State Machine Modification?},
  location = {Munich, Germany},
  cofirst = {2},
  year = {2024},
  month = nov,
  booktitle = {LangRob Workshop at Conference on Robot Learning},
}

Fast Explicit-Input Assistance for Teleoperation in Clutter
2024 IEEE/RSJ Int. Conf. Intelligent Robots and Systems (IROS), 2024conference
Nick Walker, Xuning Yang, Animesh Garg, Maya Cakmak, Dieter Fox and Claudia Pérez-D’Arpino

@inproceedings{walker2024explicit,
  author = {Walker, Nick and Yang, Xuning and Garg, Animesh and Cakmak, Maya and Fox, Dieter and P\'{e}rez-D'Arpino, Claudia},
  title = {Fast Explicit-Input Assistance for Teleoperation in Clutter},
  location = {Abu Dhabi, UAE},
  year = {2024},
  month = oct,
  booktitle = {2024 IEEE/RSJ International Conference on Intelligent Robots and Systems},
  pages = {9270-9276},
  wwwpdf = {https://hcrlab.cs.washington.edu/assets/pdfs/2024/walker2024explicit.pdf},
  wwwcode = {https://github.com/NVlabs/fast-explicit-teleop},
  doi = {10.1109/IROS58592.2024.10802138}
}

Using 3D Mice to Control Robot Manipulators
ACM/IEEE Int. Conf. Human-Robot Interaction (HRI), 2024conference
Varad Dhat, Nick Walker and Maya Cakmak

@inproceedings{dhat2024mice,
  author = {Dhat, Varad and Walker, Nick and Cakmak, Maya},
  title = {Using 3D Mice to Control Robot Manipulators},
  year = {2024},
  month = mar,
  booktitle = {ACM/IEEE International Conference on Human-Robot Interaction},
  location = {Boulder, CO, USA},
  wwwpdf = {https://hcrlab.cs.washington.edu/assets/pdfs/2024/dhat2024using.pdf},
  wwwcode = {https://github.com/hcrlab/3dmouse-hid},
  doi = {10.1145/3610977.3637486}
}

2023

A Guide to Transit-Oriented Running in Seattle
The Urbanist, 2023feature
Nick Walker

@article{walker2023transitrunning,
  author = {Walker, Nick},
  title = {A Guide to Transit-Oriented Running in Seattle},
  booktitle = {The Urbanist},
  month = nov,
  year = {2023},
  url = {https://www.theurbanist.org/2023/11/28/a-guide-to-transit-oriented-running-in-seattle/},
  keywords = {running, seattle, transit},
}

Towards robustly picking unseen objects from densely packed shelves
RSS Workshop on Perception and Manipulation Challenges for Warehouse Automation, 2023workshop
Markus Grotz, Jack Lowry, Soofiyan Atar, Yi Li, Paolo Torrado, Boling Yang, Nick Walker, Michael Murray, Dieter Fox, Maya Cakmak and Joshua R. Smith

@article{grotz2023densely,
  author = {Grotz, Markus and Lowry, Jack and Atar, Soofiyan and Li, Yi and Torrado, Paolo and Yang, Boling and Walker, Nick and Murray, Michael and Fox, Dieter and Cakmak, Maya and Smith, Joshua R.},
  title = {Towards robustly picking unseen objects from densely packed shelves},
  booktitle = {Proceedings of the RSS Workshop on Perception and Manipulation Challenges for Warehouse Automation},
  location = {Daegu, Republic of Korea},
  month = jul,
  year = {2023},
  wwwpdf = {https://robotic-manipulation.sciencehub.uw.edu/static/preprints/2023-grotz_rss.pdf}
}

Transcription analysis platform
US11837214, 2023patent
Michael J. Szentes, Carlos Chavez, Robert E. Lewis and Nicholas S. Walker
United Services Automobile Association (USAA)

@patent{szentes2023transcription,
  author = {Szentes, Michael J. and Chavez, Carlos and Lewis, Robert E. and Walker, Nicholas S.},
  title = {Transcription analysis platform},
  number = {US11837214},
  year = {2023},
  month = dec,
  day = {5},
  assignee = {United Services Automobile Association (USAA)},
  url = {https://patents.google.com/patent/US11837214},
  application = {17/084,513},
  wwwolder = {szentes2020transcription}
}

2022

Wandering Robots in the Wild
IEEE Spectrum, 2022feature
Nick Walker and Amal Nanavati

@article{walker2022wandering,
  author = {Walker, Nick and Nanavati, Amal},
  title = {Wandering Robots in the Wild},
  booktitle = {IEEE Spectrum},
  month = jul,
  year = {2022},
  url = {https://spectrum.ieee.org/wandering-robots-in-the-wild},
  keywords = {wizard of oz, wandering, in-the-wild deployment, robot navigation, robots asking for help},
}

Not All Who Wander Are Lost: A Localization-Free System for In-the-Wild Mobile Robot Deployments
2022 ACM/IEEE Int. Conf. Human-Robot Interaction (HRI), 2022conference
Amal Nanavati*, Nick Walker*, Lee Taber, Christoforos Mavrogiannis, Leila Takayama, Maya Cakmak and Siddhartha Srinivasa

@inproceedings{nanavati2022wandering,
  author = {Nanavati, Amal and Walker, Nick and Taber, Lee and Mavrogiannis, Christoforos and Takayama, Leila and Cakmak, Maya and Srinivasa, Siddhartha},
  cofirst = {2},
  title = {Not All Who Wander Are Lost: A Localization-Free System for In-the-Wild Mobile Robot Deployments},
  booktitle = {Proceedings of the 2022 ACM/IEEE International Conference on Human-Robot Interaction},
  location = {Sapporo, Hokkaido, Japan},
  month = mar,
  year = {2022},
  doi = {10.1109/HRI53351.2022.9889620},
  pages = {422–431},
  numpages = {10},
  keywords = {wizard of oz, wandering, in-the-wild deployment, robot navigation, robots asking for help},
  series = {HRI '22},
  wwwpdf = {https://hcrlab.cs.washington.edu/assets/pdfs/2022/nanavati2022wandering.pdf},
  wwwcode = {https://github.com/hcrlab/kuri_wandering_robot},
  wwwurl = {https://wandering.nickwalker.us}
}

2021

Influencing Behavioral Attributions to Robot Motion During Task Execution
5th Conference on Robot Learning (CoRL), 2021conference
Nick Walker, Christoforos Mavrogiannis, Siddhartha Srinivasa and Maya Cakmak

@inproceedings{walker2021attributions,
  author = {Walker, Nick and Mavrogiannis, Christoforos and Srinivasa, Siddhartha and Cakmak, Maya},
  title = {Influencing Behavioral Attributions to Robot Motion During Task Execution},
  booktitle = {Proceedings of the 5th Conference on Robot Learning},
  pages = {169--179},
  location = {London, UK},
  month = nov,
  year = {2021},
  editor = {Faust, Aleksandra and Hsu, David and Neumann, Gerhard},
  volume = {164},
  series = {Proceedings of Machine Learning Research},
  publisher = {PMLR},
  wwwpdf = {https://hcrlab.cs.washington.edu/assets/pdfs/2021/walker2021attributions.pdf},
  wwwposter = {https://openreview.net/attachment?id=UIaodSPHNFN&name=poster},
  wwwextra = {https://openreview.net/attachment?id=UIaodSPHNFN&name=supplementary_material},
  wwwcode = {https://github.com/nickswalker/influencing-behavioral-attributions},
  wwwolder = {walker2021influencing},
  wwwurl = {https://attributions.nickwalker.us}
}

Learning Backchanneling Behaviors for a Social Robot via Data Augmentation from Human-Human Conversations
5th Conference on Robot Learning (CoRL), 2021conference
Michael Murray, Nick Walker, Amal Nanavati, Patricia Alves-Oliveira, Nikita Filippov, Allison Sauppe, Bilge Mutlu and Maya Cakmak

@inproceedings{murray2021learning,
  author = {Murray, Michael and Walker, Nick and Nanavati, Amal and Alves-Oliveira, Patricia and Filippov, Nikita and Sauppe, Allison and Mutlu, Bilge and Cakmak, Maya},
  title = {Learning Backchanneling Behaviors for a Social Robot via Data Augmentation from Human-Human Conversations},
  booktitle = {Proceedings of the 5th Conference on Robot Learning},
  pages = {513--525},
  location = {London, UK},
  month = nov,
  year = {2021},
  editor = {Faust, Aleksandra and Hsu, David and Neumann, Gerhard},
  volume = {164},
  series = {Proceedings of Machine Learning Research},
  publisher = {PMLR},
  wwwpdf = {https://hcrlab.cs.washington.edu/assets/pdfs/2021/murray2021backchanneling.pdf},
  wwwposter = {https://openreview.net/attachment?id=0WDtVJVwBcf&name=poster}
}

2020

Human Perceptions of a Curious Robot that Performs Off-Task Actions
2020 ACM/IEEE Int. Conf. Human-Robot Interaction (HRI), 2020conference
Nick Walker, Kevin Weatherwax, Julian Alchin, Leila Takayama and Maya Cakmak

@inproceedings{walker2020perceptions,
  author = {Walker, Nick and Weatherwax, Kevin and Alchin, Julian and Takayama, Leila and Cakmak, Maya},
  title = {Human Perceptions of a Curious Robot that Performs Off-Task Actions},
  booktitle = {Proceedings of the 2020 ACM/IEEE International Conference on Human-Robot Interaction},
  location = {Oxford, UK},
  month = mar,
  year = {2020},
  doi = {10.1145/3319502.3374821},
  wwwpdf = {https://hcrlab.cs.washington.edu/assets/pdfs/2020/walker2020perceptions.pdf},
  wwwvideo = {https://www.youtube.com/watch?v=1j91ISstdH8},
  wwwextra = {https://doi.org/10.5281/zenodo.3600599}
}

Jointly Improving Parsing and Perception for Natural Language Commands through Human-Robot Dialog
The Journal of Artificial Intelligence Research (JAIR), 2020journal
Jesse Thomason, Aishwarya Padmakumar, Jivko Sinapov, Nick Walker, Yuqian Jiang, Harel Yedidsion, Justin Hart, Peter Stone and Raymond J. Mooney

@article{thomason2020improving,
  title = {Jointly Improving Parsing and Perception for Natural Language Commands through Human-Robot Dialog},
  author = {Thomason, Jesse and Padmakumar, Aishwarya and Sinapov, Jivko and Walker, Nick and Jiang, Yuqian and Yedidsion, Harel and Hart, Justin and Stone, Peter and Mooney, Raymond J.},
  volume = {67},
  journal = {The Journal of Artificial Intelligence Research},
  month = feb,
  year = {2020},
  wwwalso = {thomason2019icra},
  wwwpdf = {https://www.cs.utexas.edu/users/ml/papers/thomason.jair20.pdf}
}

2019

Open-World Reasoning for Service Robots
29th Int. Conf. Automated Planning and Scheduling (ICAPS), 2019conference
Yuqian Jiang*, Nick Walker*, Justin Hart and Peter Stone

@inproceedings{jiang2019icaps,
  author = {Jiang, Yuqian and Walker, Nick and Hart, Justin and Stone, Peter},
  cofirst = {2},
  title = {Open-World Reasoning for Service Robots},
  booktitle = {Proceedings of the 29th International Conference on Automated Planning and Scheduling},
  location = {Berkeley},
  month = jul,
  year = {2019},
  wwwpdf = {https://www.cs.utexas.edu/%7Epstone/Papers/bib2html-links/ICAPS19-Jiang.pdf},
  wwwvideo = {https://youtu.be/TLXGQDTAZvA},
  wwwurl = {https://nickwalker.us/projects/open-world-reasoning}
}

Improving Grounded Natural Language Understanding through Human-Robot Dialog
Int. Conf. Robotics and Automation (ICRA), 2019conference
Jesse Thomason, Aishwarya Padmakumar, Jivko Sinapov, Nick Walker, Yuqian Jiang, Harel Yedidsion, Justin Hart, Peter Stone and Raymond J. Mooney

@inproceedings{thomason2019icra,
  title = {Improving Grounded Natural Language Understanding through Human-Robot Dialog},
  author = {Thomason, Jesse and Padmakumar, Aishwarya and Sinapov, Jivko and Walker, Nick and Jiang, Yuqian and Yedidsion, Harel and Hart, Justin and Stone, Peter and Mooney, Raymond J.},
  booktitle = {International Conference on Robotics and Automation},
  month = may,
  year = {2019},
  doi = {10.1109/ICRA.2019.8794287},
  location = {Montreal},
  wwwpdf = {https://www.cs.utexas.edu/users/ml/papers/thomason.icra19.pdf},
  wwwalso = {thomason2020improving},
  wwwolder = {thomason2018robodial,thomason2018mrhrc},
  wwwvideo = {https://youtu.be/PbOfteZ_CJc?t=5}
}

Desiderata for Planning Systems in General-Purpose Service Robots
2019 ICAPS Workshop on Planning and Robotics, 2019workshop
Nick Walker*, Yuqian Jiang*, Maya Cakmak and Peter Stone

@inproceedings{walker2019planrob,
  title = {Desiderata for Planning Systems in General-Purpose Service Robots},
  author = {Walker, Nick and Jiang, Yuqian and Cakmak, Maya and Stone, Peter},
  cofirst = {2},
  booktitle = {Proceedings of 2019 ICAPS Workshop on Planning and Robotics},
  location = {Berkeley},
  month = jul,
  year = {2019},
  wwwpdf = {https://icaps19.icaps-conference.org/workshops/PlanRob/PlanRob_2019_submissions/PlanRob_2019_paper_9.pdf},
  wwwslides = {https://doi.org/10.5281/zenodo.3244795}
}

Neural Semantic Parsing with Anonymization for Command Understanding in General-Purpose Service Robots
RoboCup 2019: Robot Soccer World Cup XXIII, 2019symposium
Nick Walker, Yu-Tang Peng and Maya Cakmak

@incollection{walker2019robocup,
  title = {Neural Semantic Parsing with Anonymization for Command Understanding in General-Purpose Service Robots},
  author = {Walker, Nick and Peng, Yu-Tang and Cakmak, Maya},
  booktitle = {RoboCup 2019: Robot Soccer World Cup XXIII},
  location = {Sydney},
  doi = {10.1007/978-3-030-35699-6_26},
  series = {Lecture Notes in Artificial Intelligence},
  editor = {Suthakorn, Jackrit and Williams, Mary-Anne and Niemueller, Tim and Chalup, Stephan},
  publisher = {Springer},
  month = jul,
  year = {2019},
  wwwcode = {https://github.com/nickswalker/gpsr-command-understanding},
  wwwpdf = {https://hcrlab.cs.washington.edu/assets/pdfs/2019/walker2019parsing.pdf},
  wwwslides = {https://doi.org/10.5281/zenodo.3253252}
}

An Architecture for Person-Following using Active Target Search
arXiv (cs.RO) preprint, 2019working
Minkyu Kim, Miguel Arduengo, Nick Walker, Yuqian Jiang, Justin W. Hart, Peter Stone and Luis Sentis

@article{kim2019,
  author = {Kim, Minkyu and Arduengo, Miguel and Walker, Nick and Jiang, Yuqian and Hart, Justin W. and Stone, Peter and Sentis, Luis},
  title = {An Architecture for Person-Following using Active Target Search},
  year = {2019},
  month = sep,
  url = {http://arxiv.org/abs/1809.08793},
  eprint = {1809.08793},
  archiveprefix = {arXiv},
  primaryclass = {cs.RO},
}

2018

PRISM: Pose Registration for Integrated Semantic Mapping
2018 IEEE/RSJ Int. Conf. Intelligent Robots and Systems (IROS), 2018conference
Justin W. Hart, Rishi Shah, Sean Kirmani, Nick Walker, Kathryn Baldauf, Nathan John and Peter Stone

@inproceedings{hart2018iros,
  author = {Hart, Justin W. and Shah, Rishi and Kirmani, Sean and Walker, Nick and Baldauf, Kathryn and John, Nathan and Stone, Peter},
  title = {PRISM: Pose Registration for Integrated Semantic Mapping},
  location = {Madrid, Spain},
  month = oct,
  year = {2018},
  booktitle = {2018 IEEE/RSJ International Conference on Intelligent Robots and Systems},
  keywords = {semantic mapping},
  doi = {10.1109/IROS.2018.8593681},
  wwwpdf = {https://www.cs.utexas.edu/%7Epstone/Papers/bib2html-links/IROS18-hart.pdf}
}

LAAIR: A Layered Architecture for Autonomous Interactive Robots
AAAI Fall Symposium on Reasoning and Learning in Real-World Systems for Long-Term Autonomy, 2018symposium
Yuqian Jiang*, Nick Walker*, Minkyu Kim, Nicolas Brissonneau, Daniel S. Brown, Justin W. Hart, Scott Niekum, Luis Sentis and Peter Stone

@inproceedings{jiang2018fss,
  title = {LAAIR: A Layered Architecture for Autonomous Interactive Robots},
  author = {Jiang, Yuqian and Walker, Nick and Kim, Minkyu and Brissonneau, Nicolas and Brown, Daniel S. and Hart, Justin W. and Niekum, Scott and Sentis, Luis and Stone, Peter},
  cofirst = {2},
  booktitle = {AAAI Fall Symposium on Reasoning and Learning in Real-World Systems for Long-Term Autonomy},
  location = {Arlington},
  month = oct,
  year = {2018},
  wwwpdf = {http://rbr.cs.umass.edu/lta/papers/FSS-18_paper_55.pdf},
  url = {https://arxiv.org/abs/1811.03563}
}

Interaction and Autonomy in RoboCup@Home and Building-Wide Intelligence
AAAI Fall Symposium on Artificial Intelligence and Human-Robot Interaction, 2018symposium
Justin Hart, Harel Yedidsion, Yuqian Jiang, Nick Walker, Rishi Shah, Jesse Thomason, Aishwarya Padmakumar, Rolando Fernandez, Jivko Sinapov, Raymond Mooney and Peter Stone

@inproceedings{hart2018fss,
  title = {Interaction and Autonomy in RoboCup@Home and Building-Wide Intelligence},
  author = {Hart, Justin and Yedidsion, Harel and Jiang, Yuqian and Walker, Nick and Shah, Rishi and Thomason, Jesse and Padmakumar, Aishwarya and Fernandez, Rolando and Sinapov, Jivko and Mooney, Raymond and Stone, Peter},
  booktitle = {AAAI Fall Symposium on Artificial Intelligence and Human-Robot Interaction},
  location = {Arlington},
  month = oct,
  year = {2018},
  wwwpdf = {https://arxiv.org/pdf/1810.02919.pdf},
  url = {https://arxiv.org/abs/1810.02919}
}

2017

Automatic Curriculum Graph Generation for Reinforcement Learning Agents
Thirty-First AAAI Conference on Artificial Intelligence (AAAI), 2017conference
Maxwell Svetlik, Matteo Leonetti, Jivko Sinapov, Rishi Shah, Nick Walker and Peter Stone

@inproceedings{svetlik2017aaai,
  author = {Svetlik, Maxwell and Leonetti, Matteo and Sinapov, Jivko and Shah, Rishi and Walker, Nick and Stone, Peter},
  title = {Automatic Curriculum Graph Generation for Reinforcement Learning Agents},
  publisher = {Association for the Advancement of Artificial Intelligence},
  location = {San Francisco},
  month = feb,
  year = {2017},
  wwwpdf = {https://www.cs.utexas.edu/%7Epstone/Papers/bib2html-links/AAAI17-Svetlik.pdf},
  wwwposter = {https://doi.org/10.5281/zenodo.3244636},
  booktitle = {Proceedings of the Thirty-First AAAI Conference on Artificial Intelligence},
  keywords = {curriculum learning; reinforcement learning},
  doi = {10.1609/aaai.v31i1.10933}
}

Wearable ear EEG for brain interfacing
SPIE 10051, Neural Imaging and Sensing, 2017conference
Eric D. Schroeder, Nicholas Walker and Amanda S. Danko

@inproceedings{schroeder2017,
  location = {San Francisco},
  author = {Schroeder, Eric D. and Walker, Nicholas and Danko, Amanda S.},
  booktitle = {Proceedings of SPIE 10051, Neural Imaging and Sensing},
  doi = {10.1117/12.2249416},
  editor = {Luo, Qingming and Ding, Jun},
  isbn = {9781510605435},
  issn = {16057422},
  month = feb,
  title = {Wearable ear EEG for brain interfacing},
  year = {2017},
}