# V5 Drivetrains Must Have Instant Acceleration (to not overheat)

I don’t know if there’s any math that can be done to find the cutoff for this trend, but I have noticed the following:

• Drivetrains that have such low torque that it takes dozens of seconds to accelerate to max speed tend to overheat pretty quick.
• Drivetrains that have so much torque that they reach max speed instantly don’t overheat at all (under moderate use).

Would it theoretically be possible to find n given: with the heat dissipation, heat generation and torque characteristics of v5 motors, a drivetrain that accelerates to max speed in under n seconds, won’t overheat under moderate use?

moderate use

Let’s define moderate use as an average of 6 volts to the motors for 180 seconds, driving a 3kg chassis. (made up numbers)

I do not know about the math but in theory it should work.

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We don’t have enough specifications to do the math. Would need a lot of stuff like the thermal mass of the motor, the thermal conductivity of the glass infused nylon. Honestly would need a lot of informational about the internal motor we don’t have as well, inertia of the internal gears and DC motor…

What you could do that might be interesting, is make a bunch of drive trains and collect data doing consistent driving (forward and backwards until over heats) with enough cooling time between trials of course. You could plot this data and try to figure out what theoretical ratio would work best.

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It really comes down to reducing current in the motor, faster acceleration will get the motor moving and current will drop. I’m sure it’s possible to model the motor and estimate current and heating, but as you can receive both as status from the motor it may just be easier to do some experiments.

This reminds me a bit of the work Chris and I did on modeling PTCs and the smart motor library all those years ago.

( most links will be broken at this stage, too many forum migrations

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