It is no secret that aerodynamics matter. Racing without drafting, skin-tight gear and aero optimisation is unthinkable. The measure of aerodynamic efficiency is CdA, a calculation of the coefficient of drag multiplied by frontal area. In a nutshell, you want the lowest CdA value. This is a reliable reference metric when optimising for aero and for drawing out more watts for every pedal stroke.
Wind tunnels are the go-to option for athletes who need body and bike aero optimisation. In lieu of a wind tunnel testing you can rely on a skilled bike fitter. The result is that you are ‘dialled in’ and ready to hit the road or the velodrome. From the wind tunnel (or bike fitter) and intro training and racing, a number of things can change. This is where a portable measure of aerodynamic efficiency can close the gap to real-world racing.
Presented at Eurobike, the aerosensor, aerobody and aerodrome system has just been released on the crowdfunding platform indiegogo to raise funds to move into production and delivery in 2023. With a funding goal of €53,391 / AUD 77,867 and Sir Chris Hoy as a prominent brand ambassador, they have raised (€24,058 / AUD 35,087) on their first day so are off to a flying start.
The CdA meter market
The aerosensor is not the first compact CdA meter for cycling, on the market you will also find Aeropod and Notio. There have been other brands that have not been released or since retired such as Alphamantis, Red is Faster, Velosense and the SwissSide AeroSensor. But the CdA market is not sleeping, another prominent brand is BodyRocket which is due to be released in 2023 and has already tied up a few rounds of investment and gain prominent supporter over the years.
It is worth highlighting that Aeropod and Notio pushed for their own data standard as the controlling body thisisant+ did not proceed with introducing a common ANT+ Profile for CdA measurements. The aerosensor relies a modified version of the original (informal) ANT+ aero profile that was developed in unison with Garmin (who essentially control thisisant+). The efforts of Garmin in the development of the profile and CdA technology (following their purchase of Alphamantis) stalled so Aerosensor will need to petition Garmin to revive and release the profile.
The aerosensor, aerobody and aerodrome
In contrast to the Notio and Aeropod CdA meters, the aerosensor has a pod design rather than the familiar pitot tubes (prongs). The mount positions the sensor further forward and lower. In the demo model shown at the 2022 Eurobike in Frankfurt, Germany, the aerosensor was attached under a bike computer mount.
Company founder, Dr. Barney Garrood PhD, has worked as an aerodynamicist in F1 with Mercedes and Ferrari and says that this design is a result of hundreds of iterations and delivers “unprecedented accuracy in real world drag measurement.” Garrood suggests that the advantage of this design over pitot tube format is the ability of measure yaw angles and provide much greater accuracy than existing CdA meters.
Extending aero optimisation, the second building block for the system is the aerobody optical sensor that warns a rider if they are moving outside of their predefined riding position.
The optical sensor unit is mounted on the stem and caught my interest as it tracks the head, shoulders and waist position and warns if the position changes. If your head raises to far, the onscreen display will turn red so is a reminder during training when fatigue can naturally lead to riders moving outside of their optimal aero position. I tested it and it is simple, onscreen visual cues help the rider recognised if their head, chest or waist is too close or too far away from the predetermined position.
The final building block in the system is the aerodrome, a lap timer. This is external equipment that is positioned on the velodrome track. It was not built for good looks (sorry, photos are not available), just a box with some buttons and long sensor strips. This sends lap times directly to the rider on their Garmin.
In combination, the complete system is tuned towards track cycling although the CdA meter and optical sensor device can also be used on together for road cycling and obviously the will attract interest among the triathletes.
During track cycling races, riders are not permitted to have onscreen data. Even thoug bike computers can be mounted under the seat where they can’t be viewed by the rider during the race, this equipment is clearly for training and optimisation. Sensor data is available in real-time on Garmin bike computers (over the Connect-IQ app). At this stage other bike computer brands like wahoo, bryton, hammerhead, sigma and polar can’t read the data and compatibility will depend on the willingness of the brands to implement the standards.
The expected customers for the system are performance coaches and sport organisations who can incorporate it as a practical solution for real-world testing.
For the complete system, the suggested retail price is €1,336 / AUD 1,9489 and pre-orders via the indiegogo crowd-funding pre-order cost €1,001 / AUD 1,460. The equipment can also be purchased separately, just the aerosensor is €668 / AUD 975 and just the aerobody optical sensor costs €223 / AUD 325. If the indiegogo funding campaign succeeds, the expected delivery of pre-orders is February 2023.
Find out more: aerosensor.tech