TITLE

# A Parameter Optimization Method to Determine Ski Stiffness Properties From Ski Deformation Data

AUTHOR(S)
Heinrich, Dieter; Mössner, Martin; Kaps, Peter; Nachbauer, Werner
PUB. DATE
February 2011
SOURCE
Journal of Applied Biomechanics;Feb2011, Vol. 27 Issue 1, p81
SOURCE TYPE
DOC. TYPE
Article
ABSTRACT
The deformation of skis and the contact pressure between skis and snow are crucial factors for carved turns in alpine skiing. The purpose of the current study was to develop and to evaluate an optimization method to determine the bending and torsional stiffness that lead to a given bending and torsional deflection of the ski. Euler-Bernoulli beam theory and classical torsion theory were applied to model the deformation of the ski. Bending and torsional stiffness were approximated as linear combinations of B-splines. To compute the unknown coefficients, a parameter optimization problem was formulated and successfully solved by multiple shooting and least squares data fitting. The proposed optimization method was evaluated based on ski stiffness data and ski deformation data taken from a recently published simulation study. The ski deformation data were used as input data to the optimization method. The optimization method was capable of successfully reproducing the shape of the original bending and torsional stiffness data of the ski with a root mean square error below 1 N m2. In conclusion, the proposed computational method offers the possibility to calculate ski stiffness properties with respect to a given ski deformation.
ACCESSION #
59560582

## Related Articles

• The Dynamics of Ski Skating. Driessel, Kenneth R.; Fink, Philip; Hentzel, Irvin R. // UMAP Journal;Winter2004, Vol. 25 Issue 4, p375

In this article the authors presents a mathematical model to measure the synamics of ski skating and the optimization problems related to it. The classic technique, wherein the skis stay in a track parallel to the direction of motion, was replaced by a skating technique, where the ski moves at...

• By the Numbers.  // Ski;Oct2010, Vol. 75 Issue 1, p14

The article presents statistics related to skies including number of ski testers, number of skis tested, and average number of test runs per tester.

• Slope and slide. Cravatta, Matthew // American Demographics;Aug97, Vol. 19 Issue 8, p34

Presents statistics on alpine skier and snowboarder participation in cold weather entertainment based on the 1996 National Skier/Boarder opinion Survey. Statistics on the total number of ski resort attendees surveyed; Average number of days people hit the slopes; Increases in snowboarding...

• NUMEROLOGY.  // Ski;Jan2004, Vol. 68 Issue 5, p24

Presents some numerical facts about skiing.

• BY THE NUMBERS: SKIING'S 2009 TEST TEAM.  // Skiing;Sep2008, Vol. 61 Issue 1, p101

The article presents statistics on the 2009 test team of the periodical "Skiing".

• The Skiing Countdown. Lessman, Kathleen; Olsson, Helen // Skiing;Nov98, Vol. 51 Issue 3, p44

Unveils statistics on skiing since 1948. Skiing publications that are celebrating golden anniversaries in 1998.

• The skiing countdown. Olsson, Helen // Skiing;Oct98, Vol. 51 Issue 2, p44

Offers a look at some peculiar skiing statistics with a Southwestern flair in New Mexico.

• BAROMETER.  // Travel Weekly (UK);1/26/2007, p12

This article presents statistics related to the travel industry. Â£1,982 is the average price of a week's skiing holiday in Europe for a family of four. A glass of wine in Courchevel costs Â£3.30. The cheapest country for lunch is Slovenia at around Â£4.27.

• Weather Forecast Use for Winter Recreation*. Rutty, Michelle; Andrey, Jean // Weather, Climate & Society;Jul2014, Vol. 6 Issue 3, p293

Recent studies have begun to address the importance of weather information for leisure activities. This paper contributes to the understanding of how weather information is sourced, perceived, and used for the discretionary and weather-dependent winter activities of skiing, snowboarding, and...

Share