PMID- 30214415
OWN - NLM
STAT- PubMed-not-MEDLINE
LR  - 20240330
IS  - 1664-042X (Print)
IS  - 1664-042X (Electronic)
IS  - 1664-042X (Linking)
VI  - 9
DP  - 2018
TI  - A New Training Assessment Method for Alpine Ski Racing: Estimating Center of Mass 
      Trajectory by Fusing Inertial Sensors With Periodically Available Position Anchor 
      Points.
PG  - 1203
LID - 10.3389/fphys.2018.01203 [doi]
LID - 1203
AB  - In this study we present and validate a method to correct velocity and position 
      drift for inertial sensor-based measurements in the context of alpine ski racing. 
      Magnets were placed at each gate and their position determined using a land 
      surveying method. The time point of gate crossings of the athlete were detected 
      with a magnetometer attached to the athlete's lower back. A full body inertial 
      sensor setup allowed to track the athlete's posture, and the magnet positions 
      were used as anchor points to correct position and velocity drift from the 
      integration of the acceleration. Center of mass (CoM) position errors (mean +/- 
      standard deviation) were 0.24 m +/- 0.09 m and CoM velocity errors were 0.00 m/s +/- 
      0.18 m/s. For extracted turn entrance and exit speeds the 95% limits of 
      agreements (LoAs) were between -0.19 and 0.33 m/s. LoA for the total path length 
      of a turn were between -0.06 and 0.16 m. The proposed setup and processing 
      allowed estimating the CoM kinematics with similar errors than known for 
      differential global navigation satellite systems (GNSS), even though the 
      athlete's movement was measured with inertial and magnetic sensors only. 
      Moreover, as the gate positions can also be obtained with non-GNSS based land 
      surveying methods, CoM kinematics may be estimated in areas with reduced or no 
      GNSS signal reception, such as in forests or indoors.
FAU - Fasel, Benedikt
AU  - Fasel B
AD  - Laboratory of Movement Analysis and Measurement, Ecole Polytechnique Federale de 
      Lausanne, Lausanne, Switzerland.
FAU - Gilgien, Matthias
AU  - Gilgien M
AD  - Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, 
      Norway.
AD  - Center of Alpine Sports Biomechanics, St. Moritz Health and Innovation 
      Foundation, St. Moritz, Switzerland.
FAU - Sporri, Jorg
AU  - Sporri J
AD  - Department of Sport Science and Kinesiology, University of Salzburg, Salzburg, 
      Austria.
AD  - Department of Orthopaedics, Balgrist University Hospital, University of Zurich, 
      Zurich, Switzerland.
FAU - Aminian, Kamiar
AU  - Aminian K
AD  - Laboratory of Movement Analysis and Measurement, Ecole Polytechnique Federale de 
      Lausanne, Lausanne, Switzerland.
LA  - eng
PT  - Journal Article
DEP - 20180830
PL  - Switzerland
TA  - Front Physiol
JT  - Frontiers in physiology
JID - 101549006
PMC - PMC6125645
OTO - NOTNLM
OT  - alpine ski racing
OT  - center of mass
OT  - giant slalom
OT  - inertial sensors
OT  - kinematics
OT  - sensor fusion
OT  - validation
EDAT- 2018/09/15 06:00
MHDA- 2018/09/15 06:01
PMCR- 2018/08/30
CRDT- 2018/09/15 06:00
PHST- 2018/04/23 00:00 [received]
PHST- 2018/08/10 00:00 [accepted]
PHST- 2018/09/15 06:00 [entrez]
PHST- 2018/09/15 06:00 [pubmed]
PHST- 2018/09/15 06:01 [medline]
PHST- 2018/08/30 00:00 [pmc-release]
AID - 10.3389/fphys.2018.01203 [doi]
PST - epublish
SO  - Front Physiol. 2018 Aug 30;9:1203. doi: 10.3389/fphys.2018.01203. eCollection 
      2018.