Distance given two velocities

calculusdistancekinematicsspeed

I have a home trainer that is connected to an application that I am writing which needs to calculate a distance traveled given the speeds that the trainer is sending.

As such, every second, the trainer sends the instantaneous speed of the rider.

Example:

At Second 0: 10 km/h
At Second 1: 15 km/h
At Second 2: 12 km/h

..

Again, all that I receive are the speeds.

Each second, I need to calculate the total distance traveled.

Example: At second 1, I should know how far the rider has traveled (knowing the speeds from Second 0 and Second 1). At second 2, again, I would need to know how far the rider has traveled (knowing the speed at Second 1 and at Second 2) and so on.

What would be the correct way to at least approximate it?

Best Answer

I think that a simple way is to assume that the acceleration between equal time interval readings is constant which, I think, is your suggestion?

Thus the average speed between time $t=i$ and $t=i+1$ is $$\dfrac{v_{\rm i}+v_{\rm i+1}}{2}$$ and so the distance travelled in this time interval is $$\dfrac{v_{\rm i}+v_{\rm i+1}}{2}\times ((i+1)-i) = \dfrac{v_{\rm i}+v_{\rm i+1}}{2}$$