[Jizvonius]

I can't say that the difference will be that big in a 5 foot arm. However, some teams have arms much larger than that.

The statements that i made earlier were general. They were based on the fact that I've seen many an arm work well with FPs powering joints. Holding position solely with the FP is indeed sketchy. I was just saying that with a little ingenuity some of the load can be taken off the FP to make a reliable arm pivot.

Some ideas that i had for limiting backdriving of the pivot to save FPs.

-generic worm gear system. (lead angle about 20 degrees saves some efficiency but increases backdriving)

-Servo/piston controlled gear brake near motor side of gearbox

-piston FP combo with piston regulated to lower pressure(helps with movement and holding position)

Feel free to call me crazy. It's happened before. Just back it up with something.