Please join us for MSc. student, Kshitij Agarwal's thesis seminar:
Quantification of Mechanisms of Human Seated Balance Using System Identification
Date: 2018 August 17, Friday
Time: Noon - 1:00PM
Location: RTF 1-075
Abstract:
Elderly individuals and those affected by neuromuscular disorders are frequently not able to independently maintain seated balance. To develop therapies and targeted interventions for seated instability, it is essential, however, to first identify the mechanisms responsible for controlling seated balance. In this context, classical system identification techniques are a promising tool for obtaining a quantitative description of such mechanisms. Motivated by these considerations, the objective of this M.Sc. research project was to quantify, using advanced system identification techniques, the active and passive control mechanisms, the muscular dynamics, and the sensorimotor time delay in seated balance control of non-disabled individuals. Fourteen young, non-disabled individuals were perturbed while sitting using mild, mechanical surface perturbations. The across-participant variability of the non-parametric estimates of the active and active-passive control components was small. The neural dynamics were identified as a proportional-derivative (PD) controller with acceleration feedback; the sensorimotor time delay as an exponential decay function; the mechanical dynamics as a PD controller; and the muscular dynamics as a second-order transfer function. In this study, the mechanisms of seated balance have been successfully quantified for non-disabled individuals. The identified parameters can furthermore be used as a normative benchmark for quantitatively and mechanistically assessing the severity of seated imbalance in affected individuals, with the goal of optimizing rehabilitation therapies and interventions.