First Pick!

A project log for Thrifty Pick and Place

Building a Pick and Place machine on the cheap, in a repeatable way.

Alastair YoungAlastair Young 01/06/2019 at 07:220 Comments

See the comments on the video. There's a lot not working here, but it does pick and it does place.

A big hindrance here was that as soon as the pump was enabled the second arduino - configured to run the 4th axis and the lights - lost serial connectivity. This seems to be some kind of EMI. After a lot of trial and error I got past this by moving the pump to its own power supply and adding a 0.1uF cap between + and the motor casing and grounding the casing. 

Tuning and tweaking then commenced and a lot of fiddling around with the vision pipelines and I eventually got it reliably placing the SOIC-16 almost right. Rotation was still slightly random - in spite of the logs showing the vision to be happy. Then I noticed that when the pump was running, the nozzle was intermittently rotating slowly clockwise. I'm pretty sure this is the motor EMI again. The step and direction signals for the 4th axis take a several inch leap from one board to the other and probably make a great antenna. So the next step is to wrap the motor in grounded aluminum foil and if that doesn't work it is coming out of the case and being placed far away at the end of a tube.

Other snippets of learning: