Legged robot design and Van der Pol oscillator based control approach

Riadh Zaier*, Omer Eldirdiry

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

Abstract

It is widely accepted within the field of animal locomotion that the gait is generated by a central pattern generator (CPG), which is usually modelled as a nonlinear oscillator. This paper proposes a mechanical design of a bio-inspired legged robot with a passive toe joint, and proposes a control method based on the key characteristics of the CPG generating the rolling motion of the gait. The overall control system is set as a Van der Pol oscillator, and the controller is then deduced accordingly. The legged robot is modelled as an inverted pendulum with a few control parameters that can be tuned to modulate the rolling motion and make it adaptive along with the stride. The locomotion controller is structured so that the overall closed loop system exhibits a stable limit cycle. Finally, the validation of the simulation platform and the implementation results of the designed robot is reported.

Original languageEnglish
Pages (from-to)282-390
Number of pages109
JournalInternational Journal of Modelling, Identification and Control
Volume38
Issue number3-4
DOIs
Publication statusPublished - 2021

Keywords

  • biomechanical legs
  • central pattern generator
  • CPG
  • limit cycle
  • nonlinear controller
  • Van der Pol oscillator

ASJC Scopus subject areas

  • Modelling and Simulation
  • Computer Science Applications
  • Applied Mathematics

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