Hi Itpro, you may or may not know the answer to my question....I notice you say the Mychron 3 can give a power graph. I dont own one of these so I'm confused as to how it does this. My knowledge tells me you need to know the rotational velocity of the engine and the corresponding torque produced at given rpm intervals to make the graph; as in metric terms, Power (Kw) = Torque (Nm) x rotational velocity (radians/sec).
So we can get the 'rotational velocity' of the wheel no problem with the rpm feed and a few gearing calcs. I know of two ways that torque can be calculated either via a torque arm of known length exerting a force on a load sensor, or by the equation: Torque(Nm) = Inertia (kgm^2) x Rotational acceleration (radians/sec^2). Assuming its caluclated using this formula, again we can calculate the rotational acceleration of the wheel using the rpm feed, a timer (within the Mychron) and gearing calcs. My problem comes when calculating the inertia part as its going to change with every kart and so unless there is another way of calculating Torque or I'm missing something obvious I can only assume that the Mychron assumes an Inertia value? If this is right then some people are going to be unhappy when they get their kart on a rolling road and some maybe quite pleased?? Cheers
|
|