Beta Customer Support: Create a repeatable process for XYZ Calibration / offsets

[FlyingLotus1983]

This issue covers all the documentation related to what a user needs to do in order to setup a beta FPD kit to do basic PnP functionality (does not need to include solder paste, as that was not shipped with the kits. Therefore, only vacuum nozzle offsets and camera offsets are needed).

The draft of this document can be started here on this issue page, on the wiki, or even in a text editor. However, once it's somewhat solidified, it should be transferred to the official documentation page at http://firepickdelta.dozuki.com/ . The calibration procedure should a how-to guide in the root directory. It might be best to separate the one-time stuff (measuring and shimming), from the software stuff (grid measurement and barycentric setup) that might be done sporadically.

Assuming the user receives the following pieces:

1. The beta test kit
2. Laser-cut paper shims for bearing blocks
3. Laser-cut acrylic plate-to-bearing fixture
4. Single-sided grid fiducial plate
5. 8mm SMT cut-strip feeder

At a minimum, this guide should cover:

• How to get the delta mechanism bearing block -to- top-plate heights the same height, using the included laser-cut shims (2) and laser-cut fixture (3)
• How to measure the delta arm lengths, average them, and enter this info into OpenPnP machine.xml as a parameter
• How to get an accurate pulley ratio (either by using a defautl value, or by measuring it)
• How to get the arms to zero degrees, using the included laser-cut fixture (3)
• How to do measure an array of grid points on the bed, using fiducial calibraiton plate (4). This should ideally be done automatically with the camera, and possibly manually using the SMT nozzle.
• How to attach the SMT cut-strip feeder to the machine, and how to set offsets for first / last part
• How to set up bottom vision (up-looking camera). Offsets, etc.
• How to do a 'touch-off' of the SMT nozzle to the blank PCB
• How to do fiducial checks on a board
• How to do simple placements from a cut-strip feeder to a blank PCB, using double-sided tape instead of solder paste

Open issues / Blocking:

• Calibrating using the camera does not entirely remove error at the nozzle, since it is at a different Z height. How do we account for this? We have an open issue for this: #20
• Need to make delta arm length adjustable, since the beta arms weren't fixtured properly. Open issue: #23 Issue still open but no longer blocks.

[FlyingLotus1983]

Disregard the bug label.. selected the wrong red label.

[FlyingLotus1983]

@vonnieda I updated the main description, let me know if this seems reasonable?

[vonnieda]

Yep, looks good.

[FlyingLotus1983]

OK, this is is the highest priority item that I can think of at the moment (apart from #20 which blocks this issue). Let me know if anything is blocking this issue from progressing, or if there are any technical snags.