Introduction, Starting my SpotMicro

[MattthiasM]

Hi,

My name is Matthias. I currently live in Germany. I used to write software for special effects in the film industry, but always had a huge interest in robots and 3d printing.

I found SpotMicro through Thingiverse and downloaded the original probably a few days after they appeared there. It took a while, but I finally managed to print all files and I started assembly yesterday, hoping I will have a walking Spot pretty soon.

I am currently using an Arduino Due for its many pins and nice speed, but I may move to the Teensy 4.0, or even the RasPi at some point. To get force feedback from the legs, I am probably going to make a servo controller for all 12 servos that measures the servos power demand, but that is a further down on the todo list ;-)

 - Matt

[MattthiasM]

And since this is the weekend and I had a little bit of tim, here is the first preassembled arm. I am missing glue, so I can't put it together all the way just yet. 

Notes:

- make sure that all the servo horns fit before you assemble anything; it's much harder to make parts fit that are already attached
- make sure that the nuts are aligned correctly (if they are a tight fit due to tolerances)
- every leg is different; make sure you sort parts beforehand
- set the servos via software to positions that make sense; there is no way to adjust those horns without disassembling the entire leg
- the cable of the lower leg servo can be routed under the cover of the upper leg; there is a channel for that
- don't use force, use the file to make parts fit; in a second iteration, we should improve some weak spots
- the shoulder joint, although meant well, hangs in the air, not touching the servo; we should come up with a counterpart to make this stable
 - Matt

PS: the bad surface on the yellow parts comes from a bad support structure during 3D printing.

[brad]

Looks great! I'll be sure to follow how your build goes! Where did you get your servos from?

[MattthiasM]

I'll be back in the shop on Sep. 2nd. The servos are from Wishiot via Amazon and were 12 Euros a piece. The MG996R would have been 5 Euros here in Germany, again via Amazon (Longruner).