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Old 12-08-2021, 09:56 PM   #86
3doghouse
Not Yet Wild
 
Join Date: Dec 2018
Posts: 30
Default Re: Programming Software Download Here

Quote:
Originally Posted by ATrain View Post
Recalling my old high school/college physics, isn't that just the force needed to move the 639lb cart 1 ft/second?

After the cart has reached speed, moving horizontally, it just continues at that speed unless acted upon by an external force (friction, wind, etc).

So to maintain speed, it should be trivial...whether it be 25mph or 35mph.

That's why uphill, heavy load, initial acceleration, etc are the major battery drain events. Frequency of stop/go events would be a big drain even too...hadn't thought of that, but it is also irrelevant because turning up your carts speed shouldn't increase/decrease the frequency of stop/go events in your typical drive.

I think those HP measures are only true if you were moving directly vertical against gravity.
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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