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PubMed · 16002080

Determination of subject-specific model parameters for visco-elastic elements.

Cassie Wilson·Mark A King·Maurice R Yeadon
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Abstract

The determination of subject-specific model parameter values is necessary in order for a computer simulation model of human motion to be evaluated quantitatively. This study used an optimisation procedure along with a kinematically driven simulation model of the contact phase in running jumps to determine the elastic parameters of segmental wobbling masses and the foot-ground interface. Kinetic and kinematic data were obtained on running jumps for height and distance performed by an elite male high jumper. Stiffness and damping coefficients of the visco-elastic elements in the model were varied until the difference between simulation and performance was minimised. Percentage differences of 6% and 9% between the simulated and recorded performances were obtained in the jumps for height and distance, respectively. When the parameters obtained from the jump for height were used in a simulation of the jump for distance (and vice versa), there was poor agreement with the recorded jump. On the other hand, a common set of visco-elastic parameters were obtained using the data from both recorded jumps resulting in a mean difference of only 8% (made up of 7% and 10%) between simulation and performance that was almost as good as the individual matches. Simulations were not overly sensitive to perturbations of the common set of visco-elastic parameters. It is concluded that subject-specific elastic parameters should be calculated from more than a single jump in order to provide a robust set of values that can be used in different simulations.

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Biomechanical PhenomenaComputer SimulationElasticityHumansMaleModels, BiologicalTorqueTrack and FieldJournal Article

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Cassie Wilson, Mark A King, Maurice R Yeadon. 2005-07-05. Determination of subject-specific model parameters for visco-elastic elements.. https://doi.org/10.1016/j.jbiomech.2005.05.012

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