Maybe that you have been surprised to see a different speed on your bike console or GPS counter than the app. This is normal as we don't use the raw speed sent by your equipment. Let's see how we calculate your speed:
The simulation engine :
It allows operating a fair comparison between the performances produced from different models of fitness/cycling equipment, not relying on the manufacturer's engine.
Thanks to this simulation engine, the calculations are the same for all kinds of equipment, as long as they provide the Watts produced (if not we use the watt calculation that we'll see below).
This simulation engine is here to reproduce as accurately as possible the outdoor experience, taking into account the fact that you can stop pedaling to recover, without being stopped directly. Like in the real-life, you can stop pedaling in the app and continue moving forward. You can even accelerate in a descent without having to pedal, like on a real descent finally. This is possible thanks to our simulation engine.
Our simulation engine is based on the produced power, either sent directly by the equipment or being calculated by the Kinomap app if not:
Classic home trainer with a speed/cadence sensor or Exercise bikes not providing the power:
When using a home trainer with a speed/sensor, the app is taking your raw speed and manual level of resistance as inputs to estimate your energy output.
Then we get a calculated WATT value that we compute with many other parameters: the main one being the grade of the road but also your weight, kinetic energy (=your previous speed), and rolling resistance coefficients to recalculate what should be your actual speed in real life.
The main inconvenience with this kind of equipment is that we don't know which resistance level you set, because your equipment can't send it, meaning that if you set a lower resistance than expected, your calculated produced power will not be accurate as you'll certainly ride faster than if you had applied the right resistance. Same if you apply a higher resistance than expected, in fact, you probably produce more power but, as the calculation is based on the theoretical resistance, you'll certainly have a lower produced power.
Smart Trainer or power sensor or exercise bikes providing the power :
This is the most accurate experience, as there is no theoretical power estimation. If you change your gear on the bike no problem, the power sensor will measure your real effort.
When using a power sensor or a smart trainer, the app is taking your power as an input and do the same calculation, using the grade of the road but also your weight, kinetic energy (= your previous speed), and rolling resistance coefficients to recalculate what should be your actual speed in real life.