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Professional snowboarder competing at the 2008 Burton Australian Open Half-Pipe Competition. Image © www.AnarchistAthlete.com 2008

Archived article focussed on automatically calculating snowboard air time using a tech concept available now [...]

Archived article focussed on automatically calculating snowboard air time using a tech concept available now .  This article was published in an SPIE BioMEMS and Nanotechnology conference proceedings in 2007. You can now read and download the PDF version of this article at www.AnarchistAthlete.com This article is an academic publication focussed on enhancing athletic performance assessment during elite-level half-pipe snowboard training and competition.

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Article Title

Harding JW, Small JW, James DA. (2007) Feature Extraction of Performance Variables in Elite Half-Pipe Snowboarding Using Body Mounted Inertial Sensors. In BioMEMS and Nanotechnology III, edited by Dan V. Nicolau, Derek Abbott, Kourosh Kalantar-Zadeh, Tiziana Di Matteo, Sergey M. Bezrukov, Proceedings of SPIE Vol. 6799 (SPIE, Bellingham, WA, 2007) 679917.

Article Abstract

Recent analysis of elite-level half-pipe snowboard competition has revealed a number of sport specific key performance variables (KPV’s) that correlate well to score1. Information on these variables is difficult to acquire and analyse, relying on collection and labour intensive manual post processing of video data. This paper presents the use of inertial sensors as a user-friendly alternative and subsequently implements signal processing routines to ultimately provide automated, sport specific feedback to coaches and athletes. The author has recently shown that the key performance variables (KPV’s) of total air-time (TAT) and average degree of rotation (ADR) achieved during elite half-pipe snowboarding competition show strong correlation with an athlete’s subjectively judged score. Utilising Micro-Electrochemical System (MEMS) sensors (tri-axial accelerometers) this paper demonstrates that air-time (AT) achieved during half-pipe snowboarding can be detected and calculated accurately using basic signal processing techniques. Characterisation of the variations in aerial acrobatic manoeuvres and the associated calculation of exact degree of rotation (DR) achieved is a likely extension of this research. The technique developed used a two-pass method to detect locations of half-pipe snowboard runs using power density in the frequency domain and subsequently utilises a threshold based search algorithm in the time domain to calculate air-times associated with individual aerial acrobatic manoeuvres. This technique correctly identified the air-times of 100 percent of aerial acrobatic manoeuvres within each half-pipe snowboarding run (n = 92 aerial acrobatic manoeuvres from 4 subjects) and displayed a very strong12 correlation with a video based reference standard for air-time calculation (r = 0.78 ± 0.08; p value < 0.0001; SEE = 0.08 ×/÷ 1.16; mean bias = -0.03 ± 0.02s) (value ± or ×/÷ 95% CL). Read Full Paper