A Study on Characteristic Estimation of Carving Turns Using Gliding Velocity and Acting Force of Skier Gliding on Actual Snow Field

Abstract

This paper proposes a method for estimating the characteristics of carving turns using the measurement information obtained from a skier gliding on the actual snow field. Skiers control skis for making turns. The gliding velocity is changed by the rotational motion of a skier in turns. Therefore, we constructed the turn model which represents the relationship between the gliding velocity and the acting force of a skier in this study. The gliding velocity was estimated using the information from the GPS receiver and the inertial and magnetic field sensors attached to the ski boots. The acting force of the skier was measured by the 6-axis force sensors attached to between the ski boots and bindings. The skier wearing the measurement system made some carving turns in the experiment. We estimated the parameters of the turn model by applying the Kalman filter using the information obtained from the measurement system attached to the skier. The analysis results for the turn model indicated the quantitative relationship between the transverse component of the gliding velocity and the transverse and vertical components of the acting force of the skier. Furthermore, we improved the turn model considering the characteristics of skis. The analysis results for the improved model represented the characteristics of carving turns in more detail than the first turn model. The analysis method can be used for the evaluation of skier's skill and the ski design．