Linear Parameter Varying Identification of Dynamic Joint Stiffness during Time-Varying Voluntary Contractions

  title={Linear Parameter Varying Identification of Dynamic Joint Stiffness during Time-Varying Voluntary Contractions},
  author={Mahsa A. Golkar and Ehsan Sobhani-Tehrani and Robert E. Kearney},
  journal={Frontiers in Computational Neuroscience},
Dynamic joint stiffness is a dynamic, nonlinear relationship between the position of a joint and the torque acting about it, which can be used to describe the biomechanics of the joint and associated limb(s). This paper models and quantifies changes in ankle dynamic stiffness and its individual elements, intrinsic and reflex stiffness, in healthy human subjects during isometric, time-varying (TV) contractions of the ankle plantarflexor muscles. A subspace, linear parameter varying, parallel… 

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  • K. RajotteHe Wang E. Clancy
  • Engineering
    2020 42nd Annual International Conference of the IEEE Engineering in Medicine & Biology Society (EMBC)
  • 2020
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The identification results demonstrated that (a) the dynamic response of the intrinsic pathway changes systematically with joint position; and (b) the static nonlinearity of the reflex pathway resembles a half-wave rectifier whose threshold decreases and gain increases as ankle is moved to dorsiflexed position.

Identification of Time-Varying Intrinsic and Reflex Joint Stiffness

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  • D. GuarínR. Kearney
  • Biology, Engineering
    2015 37th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC)
  • 2015
A novel, nonlinear, dynamic joint stiffness model is formulated and a new algorithm is presented to estimate its parameters, assuming that the variability in the model parameters is a function of the mean joint position.

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Position dependence of ankle joint dynamics--I. Passive mechanics.

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