I'm posting this topic for both solving a couple of placement issues I have and adding that knowledge in the handbook I'm writing for this machine.
For now, after running a calibration for the nozzle, flying vision and bottom vision, I have very consistent placement results and I'm very happy with the machine. Aside of a few feeders I miss for larger parts (I finally got them in reels) that I'll purchase later,
I have 2 parts I can't place automatically because I don't know where to start,
so I'd like to discuss this here
One part is a 10x10x4 mm square inductor
it's provided in reels, I also made tray to simplify vision and placement testing. I couldn't find a way to test it correctly.
I tried defining it as a tantalum cap (TAN method, side vision), contrast and brightness would work however, the part is so large that the vision testing area is enlarged to almost all the camera FoV width (the vision "working area" is the part dimension multiplied by a coefficient) and I have a marker that is found in the right side of the camera image.
- is there a way to reduce that working area for that particular part (or for all parts, no suitable IMO but...)
- is there a way to test it with the bottom vision. Again, I tried.... but... the part is coming in the tape with the bottom pads view as up and down and for instance, if you want to check it like a QFN with the CSP methods you need pads on the left and right sides to have the symmetry working, so at the end, I would need the part to be presented in front of the camera with the pads L and R. I couldn't find a way to ask the vision to pre rotate the part of 90° before checking it, find the zero (which is actually 90°) and compute placement angle from there.
Worse, I have to confirm but I think that it might be other way around, that's because I have the part rotated 90° on the PCB that the part is pre rotated and can't be checked.
Basically I would like to define the presentation angle to the bottom cam, then have the placement angle applied.
the second part I have is a micro SD card holder (*chime sound* "holy grail"). anybody was able to place them automatically on this machine ? if so, with which method ??
actually, for both the inductor and the SD card holder, I would "just" (ahah... it's always "just" needs which sound like "simple" needs I know) need a bottom cam vision technique that takes the bounding box of a part (I just need to setup the contrast and threshold to get it right). From there, estimate a center which can be a pondered center, I don't care, then match this with my placement location by trials and errors or simply by adding placement offsets in my part def. The inductor, in particular, has only 2 BIG pads and placement accuracy isn't important.
any idea how to do that ? the new software has a LOT more in the part definition menu but I haven't tried them all and I don't know what all of them do.
thank you !
Adding a bug list to address to MDC to keep the software moving.
Here's my listing, I'll keep adding up thanks to other users ! I'm using v2.1.21.BELOW IN RED WHAT HAS BEEN CORRECTED WITH v2.1.23
- Writing in the constants will generate an error after a few edited value, if you don't leave the constant screen and keep editing. Software crashes, you might need to edit the constants in several attempts - I haven't played much (again) with the constants but I'll keep trying with 2.1.23.
- cancel the tape index during manual assembly (F6). Trying placement (and vision) on a part sourced from a feeder, you might want to replace the part yourself instead of having the tape indexing. SW prompt for index but zero doesn't cancel it. FIXED
- Tray angle. I thought it was a bug but it's the MDC answer to my request of having the tray angle better handled. Now PCB angle is only the DESIRED angle / orientation of the chip and doesn't deal with how the chip is oriented in the tray (example in post #11 below). FIXED.
- 5 key should be able to return to camera mode after nozzle mode. It works when you do teach mode => nozzle mode (9). Press 5 you return to camera vision. This does NOT work after returning from a vision test (it would be useful so that you don't have to go with the double ESC ESC to discard feeder location change) - FIXED PARTIALLY. When you come back from a vision test 5 takes you back to camera mode but when you press ESC twice you'll jump again to NOZZLE MODE.
- When playing with part def during vision test. I leave my nozzle above the tray of the part I test and I test the part over and over. Calling F3 to check (and edit) part def works the first time. Return from vision check (eventually put the part down or keep it sucked), press F3 to tweak part def again, head returns to origin. NOW WORKS - JUST DO NOT SAVE (with F2), this seems to cause the head return to the origin next time you press F3 to get the part def, for some reason. Save data once part testing is finished and when you are back to the datasheet (PCB, feeder/tray def etc).
- Assembling a panel. Once the panel is finished, I should be able to assemble another one. If I press 0 to check the bias on the new PCB I install, I move to the origin and the bias is shifted. BEWARE, if you don't correct it, it will be kept until you terminate assembly. Even if you terminate and start over, bias is lost. I need to return to PCB list, edit mode, F8 on bias point (which stayed correct in the data list), head moves to the right point, I can assemble again. FIXED (it seems)
- in the DATA list submenu, the LowCam button (right next to the nozzle exchanger menu button) doesn't work. It's supposed to take you to the bottom camera for continuous part checking but it opens the nozzle exchanger data window instead. FIXED in 2.1.23 - an updated update of the 2.1.23 has been put online on the 23/0902012 - if you got the 2.1.23 earlier, please DL it again
- terminating the assembly in emergency (F10, STOP button) when validating "TERMINATE" will turn vacuum ON while it was OFF when you pressed STOP. As a result, you must manually turn the vacuum off (I go in a feeder list, or anywhere I can go in teaching mode, then press V). If vacuum was on when assembly was interrupted, it's turned off properly though. NOT FIXED YET
- The stroke (up down) axis of the machine is referred as Z pretty much everywhere in the manual including in the system constants. It's also name U (with the associated keyboard shortcut) in teaching mode. The problem is that in the teaching mode screen, the ANGLE is name Z which makes no sense. I asked MDC if they could replace the Angle name there by theta, A, angle, anything but not Z. U can stay, I got used to it as the stroke (possibly referenced as U due to the spelling of 'stroke' in Japanese ?). FIXED - thank you !
- in the tray programming (teaching mode), only the crosshair is displayed. The bounding box of the part should be displayed too, just like for feeder programming. FIXED - brilliant, thank you !
- Mechanical synchro problem. My last placement program line is a big inductor that requires a feeder indexing of 4 piston push. At the end of the assembly of panel, the machine tries to move the feeder indexing piston back to origin while it's still indexing the feeder (generally when the piston is out, pushing on the feeder lever). As a result, many steps are slipped / missed and I need to re-home otherwise the feeder system is totally lost. It's not good at all for the machine neither. FIXED in newest 2.1.23 (28/09/2012) see changelog to be sure you have the right version
- Terminating assembly while being in manual centering (Lv=25) : you can't quit the current centering operation and the mode and software is stuck (I need to force it to terminate) FIXED.
If the manual ("semi auto") centering is canceled, the part is taken to the dump area and assembly stops.