Quote:
Originally Posted by 3doghouse
No, the main point of the calculation is wind resistance at a steady/constant speed.
The coefficient of drag and frontal area are the major factors.
The weight is really only relevant for rolling resistance, which is a relatively small part of the equation...
For example, the 639 pound cart takes 1.1 HP to go 20 MPH. Doubling the weight (1,278 pounds at 20 mph) takes only 1.4 HP, but doubling the speed (639 pounds at 40 mph) takes 6.8 HP.
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Makes sense, esp since it's a stead-state equation. The question is whether or not that extra HP is a significant amount or not in the scheme of things?
I kind of think it's a nonstarter to discuss 25mph, simply because everybody wants to go faster than that.
An empirical method, instead of theoretical, would just be to set our carts to 28mph, turn on the monitor software, then drive a bunch of straight, known-distance routes at full speed and measure the usage, then repeat at 33mph (or whatever your max is) and just compare.