The identification of vertical velocity profiles using an inertial sensor to investigate pre-impact detection of falls
Medical Engineering & Physics, In Press, Corrected Proof, Available online 20 February 2008
A.K. Bourke, K.J. O’Donovan and G. ÓLaighin
http://dx.doi.org/10.1016/j.medengphy.2007.12.003

A threshold-based fall-detection algorithm using a bi-axial gyroscope sensor
Medical Engineering & Physics, Volume 30, Issue 1, January 2008, Pages 84-90
A.K. Bourke and G.M. Lyons
http://dx.doi.org/10.1016/j.medengphy.2006.12.001
 
See also (by same authors):
Evaluation of a threshold-based tri-axial accelerometer fall detection algorithm
Gait & Posture, Volume 26, Issue 2, July 2007, Pages 194-199
A.K. Bourke, J.V. O’Brien and G.M. Lyons
http://dx.doi.org/10.1016/j.gaitpost.2006.09.012