Traditional motion planning approaches for multi-legged locomotion divide the problem into several stages, such as contact search and trajectory generation. However, reasoning about contacts and motions simultaneously is crucial for the generation of complex whole-body behaviors. Currently, coupling theses problems has required either the assumption of a fixed gait sequence and flat terrain condition, or nonconvex optimization with intractable computation time. In this letter, we propose a mixed-integer convex formulation to plan simultaneously contact locations, gait transitions, and motion, in a computationally efficient fashion. In contrast to previous works, our approach is not limited to flat terrain nor to a prespecified gait sequence. Instead, we incorporate the friction cone stability margin, approximate the robot's torque limits, and plan the gait using mixed-integer convex constraints. We experimentally validated our approach on the HyQ robot by traversing different challenging terrains, where nonconvexity and flat terrain assumptions might lead to suboptimal or unstable plans. Our method increases the motion robustness while keeping a low computation time.

Simultaneous Contact, Gait, and Motion Planning for Robust Multilegged Locomotion via Mixed-Integer Convex Optimization / Aceituno-Cabezas, B; Mastalli, C; Dai, Hk; Focchi, M; Radulescu, A; Caldwell, Dg; Cappelletto, J; Grieco, Jc; Fernandez-Lopez, G; Semini, C. - In: IEEE ROBOTICS AND AUTOMATION LETTERS. - ISSN 2377-3766. - 3:3(2018), pp. 2531-2538. [10.1109/LRA.2017.2779821]

Simultaneous Contact, Gait, and Motion Planning for Robust Multilegged Locomotion via Mixed-Integer Convex Optimization

Focchi M;
2018-01-01

Abstract

Traditional motion planning approaches for multi-legged locomotion divide the problem into several stages, such as contact search and trajectory generation. However, reasoning about contacts and motions simultaneously is crucial for the generation of complex whole-body behaviors. Currently, coupling theses problems has required either the assumption of a fixed gait sequence and flat terrain condition, or nonconvex optimization with intractable computation time. In this letter, we propose a mixed-integer convex formulation to plan simultaneously contact locations, gait transitions, and motion, in a computationally efficient fashion. In contrast to previous works, our approach is not limited to flat terrain nor to a prespecified gait sequence. Instead, we incorporate the friction cone stability margin, approximate the robot's torque limits, and plan the gait using mixed-integer convex constraints. We experimentally validated our approach on the HyQ robot by traversing different challenging terrains, where nonconvexity and flat terrain assumptions might lead to suboptimal or unstable plans. Our method increases the motion robustness while keeping a low computation time.
2018
3
Aceituno-Cabezas, B; Mastalli, C; Dai, Hk; Focchi, M; Radulescu, A; Caldwell, Dg; Cappelletto, J; Grieco, Jc; Fernandez-Lopez, G; Semini, C
Simultaneous Contact, Gait, and Motion Planning for Robust Multilegged Locomotion via Mixed-Integer Convex Optimization / Aceituno-Cabezas, B; Mastalli, C; Dai, Hk; Focchi, M; Radulescu, A; Caldwell, Dg; Cappelletto, J; Grieco, Jc; Fernandez-Lopez, G; Semini, C. - In: IEEE ROBOTICS AND AUTOMATION LETTERS. - ISSN 2377-3766. - 3:3(2018), pp. 2531-2538. [10.1109/LRA.2017.2779821]
File in questo prodotto:
File Dimensione Formato  
aceituno_mastalli17ral.pdf

accesso aperto

Tipologia: Post-print referato (Refereed author’s manuscript)
Licenza: Tutti i diritti riservati (All rights reserved)
Dimensione 1.92 MB
Formato Adobe PDF
1.92 MB Adobe PDF Visualizza/Apri
Simultaneous_Contact_Gait_and_Motion_Planning_for_Robust_Multilegged_Locomotion_via_Mixed-Integer_Convex_Optimization.pdf

Solo gestori archivio

Tipologia: Versione editoriale (Publisher’s layout)
Licenza: Tutti i diritti riservati (All rights reserved)
Dimensione 929.91 kB
Formato Adobe PDF
929.91 kB Adobe PDF   Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11572/365187
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 88
  • ???jsp.display-item.citation.isi??? 57
social impact