Aero Sock Development

Rule 28 Aero Socks were tested by Wattshop on the DriverPlan NRG DriverPlan Team Pursuit team. Multiple material textures and sock lengths were tested. The most successful of which then became our prototype socks that were then used to take three national titles at the British Track Championships.

All testing was conducted by Daniel Bigham, owner of Wattshop and now three time national champion on the track. Dan has an extensive background in aerodynamics first in Formula 1 as an aerodynamicist with the Mercedes AMG Pertronas team, then as a data analyst with Drag2Zero.

 

TEST PROTOCOL

Rule 28 Aero Socks were tested against three alternatives: No socks, 6” cotton cycling socks and a trip line competitor. 

Data was collected from a crank based powermeter that was calibrated prior to each run. Ambient weather readings were collected trackside from a mobile weather station. Readings included: air density, air temperature, air pressure and humidity. System weight (rider and bike) was also measured prior to each individual run.

The protocol itself consisted of two runs - using different time durations and speeds. Run one was a 10-minute test at 45kph. Run two was a 4-minute run at 55kph. All data points were processed in a proprietary MatLab script on a second by second basis to calculate rider CdA. The results were then averaged over the test run to give a final figure. The protocol was repeated and the readings averaged for each product tested.

 

RESULTS

From the CdA value generated from these results, a curve was plotted using MatLab of the wattage required by our test rider to produce speeds using each product. These findings can be seen below as well as plotted on a graph at the top of the page.



CONCLUSIONS

6" cotton socks: Cotton socks increase a riders frontal area, although only slightly. This by itself would not provide any noticeable change in pressure drag in the wake of the riders leg, however the knitted construction of a cotton sock drastically increases skin friction verses actual skin.

No socks: Riding with no socks reduces frontal area and doesn't increase skin friction.

Trip line competitor: Trip lines can be a good method of inducing turbulence, however they are limited in their applications. This is due to the fact that they require precise placement. In real world applications, where riders leg shape and leg velocity is variable, not only between individuals, but also at different moments of the pedalling phase. If trip lines are not correctly positioned then excess skin friction can occur as well as minimal reduction in pressure drag.

Rule 28 Aero Socks: Our Aero Socks utilise a textured material that provides surface roughness encouraging the boundary layer to turn turbulent. As the entire surface of our Aero Socks is textured, they are immune from changes in orientation or leg shape.

Our results have been replicated by Adaptive Human Performance, an Aero and Physiological Testing expert based in Victoria, Australia. They can be found on Instagram @adaptivehp

If you have any questions about our products, please fill out the form on the 'Contact Us' page and we will do our best to answer you.