Load cells and winter sports: measuring success
If like us you’ve been watching to the Winter Olympics, two things might have struck you:
- How technology must play a crucial part in testing and making sports equipment when competitors win medals by one hundredth of a second
- How ridiculously young many of the competitors are!
Whilst the second is probably a reflection of how long Richmond Industries has been making, designing and manufacturing load cells, the first is definitely true. We’re proud to say that load cells are used extensively in testing winter sports equipment and monitoring athletic performance, whether on ice or snow.
Ski-snow interaction in a carved turn
Alpine skiing rely on maintaining contact between the edges of skis and the slope at important point in a race, such as turning at high speed. Long skis such as those used in downhill need to flex whilst maintaining optimum pressure to carve a turn rather than slide sideways. A Japanese team from the Ogasaka Ski Company used load cells to measure:
“Ski deflection, contacting pressure and boot-ski force … in the long carving turn on the two skis of different bending stiffness.”
The team kitted out a pair of skies with various sensors to detect pressure, deflection and torsion, with the aim to identify force and moment equilibrium and how the ski deflected at this point.
“Four original load cells are inserted between the binding plate and the upper surface of the ski. (The) Binding plate is made of aluminum alloy plate divided into right and left plates to make a space for inserting the deflection beam. Each plate is connected to the front and the rear load cells. The force from the boot is conducted through the pin joints, which are supported by lateral beams. Strain guages are fit on the surface of the lateral beams.”
Bobsleigh starts times and curling brushes
To discover how a team at the Korea Institute of Sport Science used load cells to help their team get faster starts,
- Check out our “Perfecting the push-off” blog.
You can also scroll down our blog a little further to discover how load cells were used to measure and analyse performance in that most crucial of curling equipment, the brush!
Leap of faith: load cells and ski jumping
Ski jumping is a highly technical sport, which relies on the torque created by the jumper as they push off the end of the ramp (platform). This torque out the jumper into the position to fly, and their centre of gravity shifts forward and above their skis.
However, according to one article, a jumper only achieves a perfect launch for just 1% of launches. Former ski jumper Peter Riedel wanted to measure the approach to see if he could improve launches.
“I had the idea to fit the platform with a tight grid of force sensors in order to get a continues measurement throughout the entire jump-off.”
His team mounted load cells directly under the run-up section the end of the platform to record each jumper’s movements.
“A unique challenge was posed by the length of the athletes’ skis: they are three meters (almost ten feet) long. However, the force needs to be measured at the exact location of the athlete’s leg.”
By using a highly sensitive system, the team could gain accurate readings, creating a system that is now used in ski jump hills worldwide.
Ski jump take-off forces
In a separate study published in the Journal of Applied Biomechanics, a team used four force plates to measure the take-off forces from competitors in the 70m competition at the Calgary Winter Olympics. The team concluded that:
“The official approach velocity of the first round and relative maximum force as well as the mean relative force during the whole takeoff sequence of the second round correlated to length of jump. The mean relative forces at the end of takeoff and for the whole takeoff sequence were significantly higher among the best jumpers. … The force analyses among the jumpers do not reveal conclusive interrelationships, the fast development of the takeoff forces may be an important prerequisite for successful ski jump performance.”
Wax on, wax off
In cross-country skiing, the flex and elasticity of a ski is import. Less known is the role of wax in keeping the competitors sliding efficiently.
The ski division of Svecom developed a professional dynamometer with load cells and integrated software to:
“Determine the flex curve, the hardness and the length of the ski bridge and to identify the waxing area by determining the amount of applicable sealing wax.”
Ski manufacturer Salomon stress the importance of waxing:
“To keep your skis in good condition you will need to wax them. The more regularly you wax them, the better they will glide. Waxing cross-country skis may seem technical and expensive. This is true if you practice cross-country skiing at a highly competitive level but waxing for upkeep can also be done…(Wax) your skate skis and classic cross-country skis so you keep them gliding!”
Want to improve sports performance using load cells?
Contact us to discuss your load cell requirements, whether for research or helping your team improve to get those elusive medals.
