Biological Cybernetics

, Volume 68, Issue 4, pp 287–298 | Cite as

Hexapodal gaits and coupled nonlinear oscillator models

  • J. J. Collins
  • Ian Stewart


The general, model-independent features of different networks of six symmetrically coupled nonlinear oscillators are investigated. These networks are considered as possible models for locomotor central pattern generators (CPGs) in insects. Numerical experiments with a specific oscillator network model are briefly described. It is shown that some generic phase-locked oscillation-patterns for various systems of six symmetrically coupled nonlinear oscillators correspond to the common forward-walking gaits adopted by insects. It is also demonstrated that transitions observed in insect gaits can be modelled as standard symmetry-breaking bifurcations occurring in such systems. The present analysis, which leads to a natural classification of hexapodal gaits by symmetry and to natural sequences of gait bifurcations, relates observed gaits to the overall organizational structure of the underlying CPG. The implications of the present results for the development of simplified control systems for hexapodal walking robots are discussed.


Numerical Experiment Network Model Organizational Structure Nonlinear Oscillator Central Pattern Generator 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag 1993

Authors and Affiliations

  • J. J. Collins
    • 1
  • Ian Stewart
    • 2
  1. 1.NeuroMuscular Research Center and Department of Biomedical EngineeringBoston UniversityBostonUSA
  2. 2.Nonlinear Systems Laboratory, Mathematics Institute, University of WarwickCoventryUK

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