Ever since ancient times, skiing has been an efficient way to move in snowy terrain. Skiing emerged as a competitive sport in the latter part of the 19th century and it has since then been divided into several different disciplines: cross-country (or Nordic) skiing, downhill skiing, ski jumping etc.. Although somewhat similar, the different disciplines put very different demands on the athletes as well as on the equipment.
At Chalmers Sports & Technology, we have studied cross-country and downhill skiing, coming from two different angles: performance measurements and improved materials and equipment.
To allow for a detailed measurement ad and analysis of the skier’s performance, we have developed a ski pole handle with integrated force and motion sensors. With this handle, we are now able to measure the movement pattern of the pole at the same time as the forward-driving mechanical power exerted via the pole. We have thereby created a power meter for cross-country skiing. The data from the sensors have been analysed through deep learning to identify and differentiate between different skiing techniques. We are able to detect both differences in technique and different gears within the same technique.
On the topic of sensor integration, we have also integrated pressure sensors in an alpine ski, and demonstrated that it is thereby possible to distinguish between drift turns and carving turns in slalom skiing.
In the area of materials and equipment, we are mainly focusing on developing the use of composite materials, mainly carbon-reinforced polymers, within cross-country and downhill skiing. In today’s cross-country poles old metal designs have been replaced by more lightweight and stiff carbon fibre composite solutions, leading to an increased performance. However, with the transition from metals to composites, more and more poles break. A ski pole brake can be devastating for the athlete if it occurs in the wrong situation!
From what we have found, these pole breaks can often be related to poor composite design explained by a lack of understanding or predictive ability of failure mechanisms in laminated composites. We are therefore currently developing simulation models and methods that enable improved ski pole design through increased understanding of how the material is loaded while racing (considering both normal skiing and interaction with other skiers). This way, the significant advantages of composite materials can be utilised to a larger extent.
Similarly, we are also working towards a simulation-driven design of alpine skis, where various materials can be tested through simulation before expensive prototypes are being built. Also, having a simulation model available for the ski response allows for fast screening of many more materials than what can be analysed through physical prototyping.
Design of ski pole with increased resistance to impact (report in Swedish, English abstract included)
Improved ski pole design by thin-ply composite reinforcement
Increased impact resistance of cross-country ski poles by improved, simulation assisted composite design
Ski development with Faction Skis: Product development and FE modelling of properties of alpine skis