Chief Delphi - drivetrain acceleration model parameters

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drivetrain acceleration model parameters

Quote:

Originally Posted by Ether (Post 1291945)

Drivetrain Acceleration Model

I just wrote a script to run the model¹ with a series of different values for n, Kro, Kf, and G:

Code:

n = 4, 2

Kro= 6, 7, 8, 9, 10, 11, 12

Kf = 0.5, 0.6, 0.7, 0.8, 0.9

G = 7, 7.5, 8, 8.5, 9, 9.5, 10

Output attached.

Still looking for test data to refine the values of the parameters, especially mechanical parameters Kro, Krv, and Kf; and electrical parameters Rcom and Rone.

¹slightly modified to output a small table of time-to-distance

Re: drivetrain acceleration model parameters

Quote:

Originally Posted by Ether (Post 1308912)

Still looking for test data to refine the values of the parameters, especially mechanical parameters Kro, Krv, and Kf; and electrical parameters Rcom and Rone.

These would be very interesting values to see tested, particularly across multiple types of drivetrains. Just by playing around with numbers and their impacts, I am unsure if teams would be able to accurately measure the torque efficiency (Kf) and the rolling resistance slope (Krv). However, even just a simple rolling resistance (Kro) number, measured on different drivetrains, would be extremely useful.

The change in final speed and average amperage over a typical FRC distance (~40ft) just due to varying rolling resistance by 5-10lbs is quite substantial.

If time and work permits I will look into testing these variables before build.