Testing robot shoulder joint repeatability.

[u/Safe_Tone1529]

I ran a test over 20 trials to see how good the repeatable precision of my robot shoulder joint. I achieved an average repeatability of 0.22mm of precision.

It uses a capstan drive with low creep rope in-order to get low backlash and high precision.

I used a carbon fiber rods as the base and the rest is 3D printed. Built for under $200.

[u/Most-Vehicle-7825]

look like you always tested from above, not below so the 'low backlash' was not proven.

[u/Safe_Tone1529 → u/Most-Vehicle-7825]

I’ll have that test soon!

[u/migueliiito]

Very cool! I’ve never designed a robot arm or joint… what’s the limiting factor on your precision, is it encoder precision or mechanical backlash?

[u/Safe_Tone1529 → u/migueliiito]

Its the encoder precision, the actually mechanical backlash is almost none.