Improved CPG Model Based on Hopf Oscillator for Gait Design of a New Type of Hexapod Robot

  • Xiangyu Li
  • Hong Liu
  • Xuan WuEmail author
  • Rui Li
  • Xiaojie Wang
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11741)


We proposed and designed a new type of hexapod robot leg structure with four-bar linkage mechanism to replace the most used bare joints for hexapod robots. The new design reducing the weight of the legs as well as the robot body inertia could offer a way to control the hexapod robot easily by using the knee joints. Based on this design, we developed CPG (central pattern generator) model using Hopf oscillator for a multi-leg coupling model which possesses a ring-type CPG network composed of six CPG units. The advantage of the improved CPG model needs one Hopf oscillator for each leg that could improve the stability of the model. The model output signals are converted to the angular trajectories of the hip joint and the knee joint through a mapping function. Simulation and experiment show that the CPG network outputs stable and smooth signals with steady phase differences, which can achieve a smooth walking statue for the hexapod robot under the triangular gait mode.


Hexapod robot Four-bar linkage mechanism Central pattern generators Hopf oscillator 


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Xiangyu Li
    • 1
    • 2
  • Hong Liu
    • 2
  • Xuan Wu
    • 2
    Email author
  • Rui Li
    • 1
  • Xiaojie Wang
    • 2
  1. 1.Engineering Research Center of Automotive Electronics and Embedded SystemChongqing University of Posts and TelecommunicationsChongqingChina
  2. 2.Institute of Advanced Manufacturing Technology, Hefei Institute of Physical ScienceChinese Academy of SciencesChangzhouChina

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