Cross country racing skis are usually hand built, which can lead to significant variations between individual skis even within the same model. These variations can have a huge impact on performance, so the ability to identify which skis have the highest quality and best characteristics is vital for high level athletes and technicians when selecting skis. 

Traditionally, this ski picking process has been done by hand, generally relying on human aptitude and judgment, that requires years of practice to truly master.  

Gear West's top ski fitters felt there must be a better way - one that was quantifiable, repeatable, and which could easily be taught to employees and discerning customers. They wanted to investigate the pressure distribution characteristics of cross country racing skis and quantify and characterize what made a ski good or bad.  To do this, needed an easy to use force or pressure sensor that could help them collect accurate and precise data.  For this they turned to Loadstar Sensors' iLoad Mini miniature load cell kits.

 

 

Four Load Cell Kit with USB Output

The kit consists of four iLoad mini miniature load cells (just 1.25" in diameter) with threaded tips (as shown below) to which we can attach our own custom adapters on which we can support the skis and apply pressure to them.  Four of the iLoad Mini Load Cells are attached to one four-port USB load cell interface called the DQ-4000U.

Over the course of two summers and race seasons, Gear West developed a Flex Testing machine that can accurately and repeatably collect pressure distribution data for skis. The "Flex Tester" used thirteen such sets hooked up to two seven port USB hubs to develop a tester that could measure pressure at 52 points along the length of a ski and log and plot data on a PC and allows for side-by-side comparison of data from up to twelve individual skis at any given time.  Distribution graphs can also be printed off for each ski, providing ski fitters with enough data to quickly sort through inventory. Finally, it can generate reports which provide further insight into a ski's behavior by calculating the values and rates of change for several metrics over the course of the load cycle.
Complete Flex Tester	Graph of force measured along length of ski	iLoad Mini Load Cell	Flex Tester Shown applying pressure

"Loadstar's unique digital USB solution helped us to develop this solution in a relatively short time frame.  In addition to their high reliability, the small form factor of the iLoad Mini means it is the only load cell on the market that can provide sufficient resolution when measuring linear pressure along the ski base. The DQ-4000 interface boxes, meanwhile, make data transmission remarkably simple; by linking 13 DQ-4000’s internally via a basic USB hub, all 52 iLoad sensors can be read and controlled through a single external USB connection.  With the simplicity and precision the iLoad system provides, Gear West is able to use the Flex Tester to test suppliers' entire race ski inventories and select the absolute highest quality skis to sell to their customers." said Josh Doebbert of Gear West.  

"We thank Loadstar Sensors for providing us excellent products and phenomenal support to help us develop this unique innovative system to characterize skis and improve skier performance!" added Matt Liebsch of Gear West.