eprintid: 10204330
rev_number: 8
eprint_status: archive
userid: 699
dir: disk0/10/20/43/30
datestamp: 2025-02-05 08:30:46
lastmod: 2025-02-05 08:33:18
status_changed: 2025-02-05 08:30:46
type: article
metadata_visibility: show
sword_depositor: 699
creators_name: Apraez, Daniel Ordoñez
creators_name: Turrisi, Giulio
creators_name: Kostic, Vladimir
creators_name: Martin, Mario
creators_name: Agudo, Antonio
creators_name: Moreno-Noguer, Francesc
creators_name: Pontil, Massimiliano
creators_name: Semini, Claudio
creators_name: Mastalli, Carlos
title: Morphological symmetries in robotics
ispublished: inpress
divisions: UCL
divisions: B04
divisions: F48
keywords: Symmetric dynamical systems; Morphological symmetries; Geometric Learning; Physics-Informed priors
note: This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions.
abstract: We present a comprehensive framework for studying and leveraging morphological symmetries in robotic systems. These are intrinsic properties of the robot’s morphology, frequently observed in animal biology and robotics, which stem from the replication of kinematic structures and the symmetrical distribution of mass. We illustrate how these symmetries extend to the robot’s state space and both proprioceptive and exteroceptive sensor measurements, resulting in the equivariance of the robot’s equations of motion and optimal control policies. Thus, we recognize morphological symmetries as a relevant and previously unexplored physics-informed geometric prior, with significant implications for both data-driven and analytical methods used in modeling, control, estimation and design in robotics. For data-driven methods, we demonstrate that morphological symmetries can enhance the sample efficiency and generalization of machine learning models through data augmentation, or by applying equivariant/invariant constraints on the model’s architecture. In the context of analytical methods, we employ abstract harmonic analysis to decompose the robot’s dynamics into a superposition of lower-dimensional, independent dynamics. We substantiate our claims with both synthetic and real-world experiments conducted on bipedal and quadrupedal robots. Lastly, we introduce the repository MorphoSymm to facilitate the practical use of the theory and applications outlined in this work.
date: 2025-01-10
date_type: published
publisher: SAGE Publications
official_url: https://doi.org/10.1177/02783649241282422
oa_status: green
full_text_type: other
language: eng
primo: open
primo_central: open_green
verified: verified_manual
elements_id: 2266058
doi: 10.1177/02783649241282422
lyricists_name: Pontil, Massimiliano
lyricists_id: MPONT27
actors_name: Flynn, Bernadette
actors_id: BFFLY94
actors_role: owner
funding_acknowledgements: PID2023-151184OB-I00 [Spanish Ministry of Science, Innovation, and Universities MCIU]; [State Research Agency AEI]; [European Regional Development Fund ERDF]; PE000013-CUP-J53C22003010006 [PNRR-MUR Project]; [European Union]
full_text_status: public
publication: The International Journal of Robotics Research
pages: 24
issn: 0278-3649
citation:        Apraez, Daniel Ordoñez;    Turrisi, Giulio;    Kostic, Vladimir;    Martin, Mario;    Agudo, Antonio;    Moreno-Noguer, Francesc;    Pontil, Massimiliano;         ... Mastalli, Carlos; + view all <#>        Apraez, Daniel Ordoñez;  Turrisi, Giulio;  Kostic, Vladimir;  Martin, Mario;  Agudo, Antonio;  Moreno-Noguer, Francesc;  Pontil, Massimiliano;  Semini, Claudio;  Mastalli, Carlos;   - view fewer <#>    (2025)    Morphological symmetries in robotics.                   The International Journal of Robotics Research        10.1177/02783649241282422 <https://doi.org/10.1177/02783649241282422>.    (In press).    Green open access   
 
document_url: https://discovery.ucl.ac.uk/id/eprint/10204330/1/2402.15552v3.pdf