At BKOOL, speed is calculated based on power. The speed does not take into account the diameter of the wheel, the pedaling cadence or gears used. We take into account other factors, such as:
- Gravity: If you are on an ascent, you must fight against gravity, but if you are on a descent, then gravity will help you.
- Rolling resistance: friction between the wheels and the road surface will slow you down. The bumpier the road, the greater your weight or the bicycle one, the more friction you will experience.
- Air resistance: As you ride your bike, your bike and your body must push air around them, similar to how a snow plow pushes snow out of the way. The resistance of the air depends directly on the speed at which you are going.
To overcome all those factors that hold us back when moving, we need to apply force. We call this watts.
It is increasingly common to train using a powermeter as the main data source, the cycling world has been focusing more on watts-based training.
Although it is true that velocity can be calculated in several ways, at BKOOL we have decided to opt for Newton's second law in which it is said that force = mass x acceleration.
Using this formula and knowing environment parameters, we can calculate acceleration at any given time. Finally, we calculate the speed as acceleration times time.
The good thing about this method is that it solves many things at once:
- The error in the measurement of watts is very small so that the speed is more accurate.
- Allows any user, regardless of their configuration, to compete.
- Avoid cheaters because it is more difficult to trick the watt data.
Comparison with data from Garmin or other sensors
If you synchronize your trainer to a Garmin device (or similar), note that the data displayed will not be the same. This is because the Garmin device is displaying data directly from the trainer, without any correction. In the search of a better and more realistic experience, the data you see in the simulator has been adjusted according to the power and weight of the user, in addition to the slope and wind speed of the route.
We will continue working to make the simulation more and more realistic.