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Updated: May 31, 2026

Experimental Methods to Study Human Postural Control
Published on: September 11, 2019
Modelling human balance using switched systems with linear feedback control
Piotr Kowalczyk1, Paul Glendinning, Martin Brown
1School of Computing, Mathematics and Digital Technology, John Dalton Building, Manchester Metropolitan University, Chester Street, Manchester M1 5GD, UK. p.kowalczyk@mmu.ac.uk
Abstract:
We are interested in understanding the mechanisms behind and the character of the sway motion of healthy human subjects during quiet standing. We assume that a human body can be modelled as a single-link inverted pendulum, and the balance is achieved using linear feedback control. Using these assumptions, we derive a switched model which we then investigate. Stable periodic motions (limit cycles) about an upright position are found. The existence of these limit cycles is studied as a function of system parameters. The exploration of the parameter space leads to the detection of multi-stability and homoclinic bifurcations.
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