Nonparametric Identification of Time-Varying Human Joint Admittance

Abstract In this study, a nonparametric method, developed in Lataire et al. (2012), is applied to the identification of linear time-varying human joint admittance. The aim of the method, denoted Skirt Decomposition method, is to reconstruct the time-varying system function. The main contribution of the paper is to evaluate the possibilities and limitations of the method for the identification of linear time-varying human joint admittance in simulation. The proposed method delivers an estimate of linear time-varying joint admittance from a single experimental trial, provided that a multisine is used as excitation signal. The trade-off between i) the frequency resolution of the dynamics, and ii) the allowable complexity of the time variation is explored.

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