Repository logo

Infoscience

  • English
  • French
Log In
Logo EPFL, École polytechnique fédérale de Lausanne

Infoscience

  • English
  • French
Log In
  1. Home
  2. Academic and Research Output
  3. Journal articles
  4. Learning control Lyapunov function to ensure stability of dynamical system-based robot reaching motions
 
research article

Learning control Lyapunov function to ensure stability of dynamical system-based robot reaching motions

Khansari-Zadeh, S. Mohammad  
•
Billard, Aude  
2014
Robotics And Autonomous Systems

We consider an imitation learning approach to model robot point-to-point (also known as discrete or reaching) movements with a set of autonomous Dynamical Systems (DS). Each DS model codes a behavior (such as reaching for a cup and swinging a golf club) at the kinematic level. An estimate of these DS models are usually obtained from a set of demonstrations of the task. When modeling robot discrete motions with DS, ensuring stability of the learned DS is a key requirement to provide a useful policy. In this paper we propose an imitation learning approach that exploits the power of Control Lyapunov Function (CLF) control scheme to ensure global asymptotic stability of nonlinear DS. Given a set of demonstrations of a task, our approach proceeds in three steps: (1) Learning a valid Lyapunov function from the demonstrations by solving a constrained optimization problem, (2) Using one of the-state-of-the-art regression techniques to model an (unstable) estimate of the motion from the demonstrations, and (3) Using (1) to ensure stability of (2) during the task execution via solving a constrained convex optimization problem. The proposed approach allows learning a larger set of robot motions compared to existing methods that are based on quadratic Lyapunov functions. Additionally, by using the CLF formalism, the problem of ensuring stability of DS motions becomes independent from the choice of regression method. Hence it allows the user to adopt the most appropriate technique based on the requirements of the task at hand without compromising stability. We evaluate our approach both in simulation and on the 7 degrees of freedom Barrett WAM arm. (C) 2014 Elsevier B.V. All rights reserved.

  • Details
  • Metrics
Type
research article
DOI
10.1016/j.robot.2014.03.001
Web of Science ID

WOS:000336468400004

Author(s)
Khansari-Zadeh, S. Mohammad  
Billard, Aude  
Date Issued

2014

Publisher

Elsevier

Published in
Robotics And Autonomous Systems
Volume

62

Issue

6

Start page

752

End page

765

Subjects

Robot point-to-point movements

•

Imitation learning

•

Control Lyapunov function

•

Nonlinear dynamical systems

•

Stability analysis

•

Movement primitives

Editorial or Peer reviewed

REVIEWED

Written at

EPFL

EPFL units
LASA  
Available on Infoscience
June 23, 2014
Use this identifier to reference this record
https://infoscience.epfl.ch/handle/20.500.14299/104581
Logo EPFL, École polytechnique fédérale de Lausanne
  • Contact
  • infoscience@epfl.ch

  • Follow us on Facebook
  • Follow us on Instagram
  • Follow us on LinkedIn
  • Follow us on X
  • Follow us on Youtube
AccessibilityLegal noticePrivacy policyCookie settingsEnd User AgreementGet helpFeedback

Infoscience is a service managed and provided by the Library and IT Services of EPFL. © EPFL, tous droits réservés