Gearbox -physics related question

[MrForbes]

In a nutshell, what it means is that you're probably not going to gain the benefit you though you might, from lightening the rotating parts in a robot gearbox.

Originally Posted by sporno

If i cheesed a couple of the gears in the AM , or KOP gearboxes , decreasing rotational inertia , and rotational mass , would that have any effect aside from just cutting weight?


would it actually put more power to the ground , and create less drive train power loss?

It would put a little bit more power to the ground as you are bringing the robot up to speed--that is, it would help you win a "drag race" against another robot. But it will not give you any more pushing power, because once it is up to speed (or when it is standing still) there is no more gain from the lightening.

The idea might be useful for an arm, though, as it will take less power to raise an arm that has less inertia. So, when you are doing arm design, keep the weight at the outer end to a minimum!