Departmental Papers (ESE)


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We demonstrate the physical rearrangement of wheeled stools in a moderately cluttered indoor environment by a quadrupedal robot that autonomously achieves a user's desired configuration. The robot's behaviors are planned and executed by a three layer hierarchical architecture consisting of: an offline symbolic task and motion planner; a reactive layer that tracks the reference output of the deliberative layer and avoids unanticipated obstacles sensed online; and a gait layer that realizes the abstract unicycle commands from the reactive module through appropriately coordinated joint level torque feedback loops. This work also extends prior formal results about the reactive layer to a broad class of nonconvex obstacles. Our design is verified both by formal proofs as well as empirical demonstration of various assembly tasks.

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Sponsor Acknowledgements

This work was supported in part by AFRL grant FA865015D1845 (subcontract 669737-1) and in part by ONR grant #N00014-16-1-2817, a Vannevar Bush Fellowship held by the last author, sponsored by the Basic Research Office of the Assistant Secretary of Defense for Research and Engineering.

Document Type

Conference Paper

Subject Area

GRASP, Kodlab

Date of this Version


Publication Source

IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS)

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reactive and sensor-based planning, legged robots, task planning, collision avoidance

Bib Tex

@InProceedings{vasilopoulos_topping_vegabrown_roy_koditschek_2018, Title = {{Sensor-Based Reactive Execution of Symbolic Rearrangement Plans by a Legged Mobile Manipulator}}, Author = {V. Vasilopoulos and T. Turner Topping and W. Vega-Brown and N. Roy and D. E. Koditschek}, Booktitle = {IEEE/RSJ International Conference on Intelligent Robots and Systems}, Year = {2018}, Pages = {3298-3305}}



Date Posted: 27 July 2018

This document has been peer reviewed.