Considering current issues in complex instrumentation (e.g., treadmill, marker-based motion capture system and force sensors), which restricts the movement analysis in laboratory setting, a convenient solution for motion capture in field activity and snow sport is the use of body worn sensors. Wearable systems using inertial measurement units (accelerometers and gyroscopes) have been proposed in a variety of sport disciplines, but their application to skiing and particularly Nordic skiing is new. Starting with results obtained in ski jumping based on wearable inertial measurement unit (IMU), this presentation highlights the relevance of IMUs for Nordic skiing movement analysis. New methods based on IMUs fixed on skis, poles and body segments are proposed to align sensors with body segments and to estimate spatio-temporal parameters and lower limbs angles for the diagonal stride in classical cross-country skiing. Inspired from IMU-based techniques for gait analysis, algorithms for drift free estimation of speed and angles are outlined and validated against a marker based motion capture system during treadmill skiing. Good accuracy and precision were obtained for detecting each cycle, thrust and pole push phases as well as for estimating cycle speed, cycle length, shank and thigh angles. The system was also sensitive to changes of speeds and inclines and offers a very easy setup to provide an unlimited capture volume for measurements on snow. Possibilities for extension to the skating style are discussed. --- The hosting University of Jyväskylä is planning to publish conference proceedings "Science and Nordic Skiing III". In case you are interested in this publication please contact the editors (Anni Hakkarainen anni.s.j.hakkarainen@jyu.fi) to become registered for the book.
© Copyright 2015 3rd International Congress on Science and Nordic Skiing - ICSNS 2015. 5-8 June 2015, Vuokatti, Finland. Veröffentlicht von University of Jyväskylä; University of Salzburg. Alle Rechte vorbehalten.