I appreciate that, I will figure out a way to test it. My thoughts are a 3hp motor, and just mount the brake rotor to the shaft and turn it on and measure the time and final rpm. I don’t have to match my speed of 1500 rpm since I can just use the formula that was written. The correct one.
No one has decided anything, do you agree with any of the torque and horsepower answers? No need to dodge around question by saying what is useful or what has been done or not been done. Everyone already gets that.
I’m asking a question regarding torque and horsepower based on the weight and...
I'll try not to do that, just didn't want repeat questions from the initial post, i'll put the edits in the footnotes. Can you help on the calculation, Greg got around 2Hp, I got around 30 Hp.
I'm just changing when i want to do the accelerating and decelerating and over a different period of time. Linearly doesn't matter because the vehicle has to carry that load no matter what, i'm asking for the calculation of what the engine needs to turn that brake rotor.
I’m okay on the inertia being the same any place but the force or in my case the torque and horsepower required to accelerate the 30 some pound rotor disc from 700rpm to 1500rpm in 4 seconds is about 2Hp?
What Chatgpt drew up looks just like an electric motor with some screws going every which way that I said it was strange but it’s just an illustration, the actual modes Chatgpt came up with is written after the illustration.
Getting back to the system and calculations, yes you can use the...
Correct. I think even 0-60mph(0 rpm to 700 wheel rpm), if you don't need the brake, and the brake rotor is free wheeling, I think it will free up some horsepower.
Respectively no thanks. I'm going to stick to my numbers so we can all stay on the same page and get the right calculation.
Going back to Gregs calculation, using all metric and mass units,
"T=21*.6=12 Nm
Hence power is 115*12 W, about 1.5 kW, or 2 hp"
It takes 2Hp, to rotate a brake rotor...
This seems more reasonable, thank you. Should you use gravity acceleration when doing metric? which would be .6 kg/m^2 x 9.81 m/s^2, which gets you to 5.8 N/m^2 multiply this by acceleration 21 rad/sec gets you 123.6 Nm or 90 ft-lb.
Then i should complain to this calculator
https://www.omnicalculator.com/physics/mass-moment-of-inertia
What unit would you prefer the calculator has most of them?
15” rotors are pretty heavy. I think it’s not uncommon these days. Camaro’s have 390mm discs. But back to the calculations, anything look off to you all? ( the rotor is weight is exact, unless my digital scale is wrong)
As I stated, the rotor is fully locked with the wheel when the system is engaged. Doesn't matter if you're going in reverse or not. Think of a dog gear teeth on a gear, (one set on the rotor and other set on the wheel hub) ignore the synchros for now:
I'm not sure if you're getting what I wrote, the system disengages and engages, so there is no moving backwards because rotor is fully locked with the wheel hub when the system engages. I'm talking about non braking events. It better be locked when you brake(reason you want it normally...
The wheel tire combo is 49.3lbs, versus 31.4 lbs brake rotor, that has a good amount of inertia, 45.64ft-lbs^2 versus 8.36ft-lbs^2(brake rotor), but are my numbers correct?. Which then equates to the tire/wheel (49lbs, outer radius 14" and inner 8.5"), taking 942.75lb⋅ft and 197hp, so i feel...
