Sunday, January 19, 2014

Meeting #1 - Notes

It took us a while, but EAST Knowledge managed to conduct its first "official" meeting at the Multnomah County Library in Gresham. We'd like to thank the library for providing a space and hosting our group.

Leading off our ongoing talk series was Pat Nystrom who was kind enough to bring in his prototype pick-and-place machine. Pat gave a very thorough overview, some of which I will attempt to capture below. You will find links to other resources at the end of this post.

Pat's overall goal is to create a pick-and-place machine that is suitable for enthusiasts as well as businesses that may require small production runs. Competing devices are either expensive (starting at $4000) or inadequate for the money, and as electronic components have shrunk (driven in large part from demand from ultra portable cell phones), it has become more difficult for enthusiasts to hand assemble boards. Keep in mind that there are electronic components that are no bigger than grains of sand.

Pat's basic concept for his machine is to combine what people do best with what machines do best. The steps for board assembly would be:
  1. Place the PCB to be assembled on to the machine (solder paste already applied)
  2. Human user identifies the appropriate part and guides pick-and-place head to pick up the part by manual manipulation. The clutches on the machines are disengaged, so movement can be very fluid and precise.
  3. Once the part is picked up, the machine is then commanded to place the part onto the PCB. The part stays in place due to the stickiness of the solder paste.
  4. Once all the parts are placed, the PCB can be placed in an oven for final steps of production.
Pat is looking to achieve .001" parts placement resolution, and the maximum PCB size is mostly guided by practical concerns.

This is the 17th version of the device, and Pat has been working on it off and on since 2006. Perseverance is key. Pat has been keeping a relentless focus on price and performance. He has been incorporating the following into his project:
  • 80/20 for rigid structure and bearing guides
  • Laser cut acrylic for mounts and other mechanical portions (done by PSU in the Electrical Prototyping Lab, but ADX can provide that service as well)
  • Fused depositional 3D printed pieces for miscellaneous and complicated parts (Pat's own)
  • Inexpensive, high-quality bearings
  • Hall sensors for always active position tracking
  • Custom designed distributed control systems (eliminates cable problems)
  • 4 gram hobbyist servos for clutch mechanisms
Pat is hoping to develop products that can be sold for around $1000 and is contemplating some kit forms too. He additionally discussed some ideas for creating solder stencils from parchment paper. Although he may discuss that more at another time.

This was a wonderful meeting, and we thank Pat for taking the time to share what he's been working on.

We hope to see you at our next talk in March! We'll have cookies and coffee!

Links to resources

  1. Pat's business
  2. A quick but thorough video explaining mass production of PCBs
  3. Pick-and-place machine on wikipedia
  4. 80/20
  5. PSU's EPL also on PSU's site.
  6. ADX
  7. MacMaster-Carr
  8. Digikey