Fuzzy-CPG Hybrid Control of a Hip Joint Walking Assist Device Based on Soft Sensing of Muscle Forces

  • Xingsong Wang
  • Fengpo Du
  • Jigang XU


To meet the vast request of the elder people with moving function impairment in the coming aging society, a prototype of hip joint walking assist device was develop. Based on the detailed analyzing of the variation characteristics of the muscle force during one gait cycle, a hybrid control algorithm was developed, which melted fuzzy control and CPG-based learning control. Fuzzy control algorithm is developed respecting the angular velocity, angular acceleration of the hip-joint of the device and the muscle force during the gait period. To releasing of the dragging force between the device and the wearer, the CPG learning algorithm is designed to study the output of the fuzzy control algorithm in stable walking state and thereafter taking over the stable state control of the device. Experiments showed the effectiveness of the proposed method.


Hip joint assist device Fuzzy-CPG hybrid control Soft sensing Muscle force 


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© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.School of Mechanical EngineeringSoutheast UniversityNanjingChina

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