An analytical model to quantify the impact of uncertainty propagation in the knee joint angles
FONSECA ; ARMAND ; DUMAS
Type de document
COMMUNICATION AVEC ACTES INTERNATIONAL (ACTI)
Langue
anglais
Auteur
FONSECA ; ARMAND ; DUMAS
Résumé / Abstract
Joint kinematics can be described by Euler angles or attitude vector and its projection on the joint axes. Whatever the notation, the uncertainties present in gait measurements affect the computed kinematics, especially at the knee joint. The objective of this study was to derive an analytical model to evaluate the impact of uncertainty propagation on the knee joint angle computation. Multi-session gait data acquired from one adult asymptomatic participant was used as reference data. The results showed that uncertainty of 5° on the input parameters matched the experimental variability. Considering each uncertainty independently, the cross-talk effect resulted from either uncertainty on the attitude vector orientation or uncertainty on the first joint axis orientation. We concluded that the model successfully estimated the propagation of input uncertainties on the joint angles and allows investigation of how this propagation occurs. The model can be used to a priori estimate the standard deviations of the experimental kinematics curves based on expected uncertainties.
