Citation

Honarvar MH, Nakashima M. J. Biomech. 2014; 47(2): 560-567.

Affiliation

Department of Mechanical and Environmental Informatics, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, 152-8552 Tokyo, Japan. Electronic address: hadi@nagoya.riken.jp.

Copyright

(Copyright © 2014, Elsevier Publishing)

DOI

10.1016/j.jbiomech.2013.09.028

PMID

24321443

Abstract

The control of balance is a primary objective in most human movements. In many cases, research or practice, it is essential to quantitatively know how good the balance is at a body posture or at every moment during a task. In this paper we suggest a new measure for postural upright stability which assigns a value to a body state based on the probability of avoiding a fall initiation from that state. The balance recovery problem is solved for a population sample using a strength database, and the probability of successfully maintaining the balance is found over the population and called the probability of recovery (PoR). It, therefore, describes an attribute of a body state: how possible the control of balance is, or how safe being at that state is. We also show the PoR calculated for a 3-link body model for all states on a plane, compare it to that found using a 2-link model, and compare it to a conventional metric: the margin of stability (MoS). It is shown, for example, that MoS may be very low at a state from which most of the people will be able to easily control their balance.

Language: en