Kilian's Robot Shop of Horrors - 03/29/2002

Click thumbnails for a larger view.

Subject: [TCRG] RSOH (Preview)
Date: Sat, 30 Mar 2002 11:59:23 -0600 (CST)
From: Alan Kilian
To: tcrobots@orbis.net (Twin Cities Robots Group)

Man, we had a great time last night. The assembly of the 4-channel PID motor controller went superb!
And it even works the first time!!!
Here is a preview.
http://bobodyne.com/web-docs/robots/Trippy/Board/index.html
Jeff took almost 30 pictures, so we will take some time to sort them out, and get them up. We really tried hard to document the SMD soldering things we learned. The best news is that it was almost trivial to solder the parts down using just one of those giant desk magnifying lenses with the circular light. And a soldering iron!
Jeff also got all the SMD parts soldered onto two of the open source motor controller boards, so he will be making progress on testing those out also.
Brynn found some really cool 5-speed with reverse transmissions that have electrically operated clutches to shift. (At Ax-Man) These would be cool in an electric kiddie car.
Everyone got dinner on me last night. (So to speak)
It was snowing so hard that I had trouble seeing the road on the way to Perkins at 2:30 AM, and on the drive back at 4:00, the sky was clear, and you could see the just-past full moon.
-Alan

New photography technique

Using a small lens as a
magnifier on a cheap
fixed-focus camera.

A dramatic example.

This is a good comparison.
The SO14 (IC4) looks bigger
that the SO28 PIC (IC5).

Otherwise, this is
the closest I can get.

Alan's motor controller project

The soldering setup. A magnifier and some tweezers.	Alan is checking some continuity before we start.	More continuity checking.	This is how the board looks through the magnifier. We used this both for probing and soldering.
We found this void by visual inspection. (The small round spot in the trace just above the third pin from the left.)	We found this void by visual inspection. (There is a hole about 75% of the trace width. The trace is 40mils wide.) But both of these still had continuity.	Alan had this flux pen. You push down and the flux flows out.	Soldering the first test part after applying flux.
The first test part. Has a little more solder than it needs.	After cleaning up pins 1-7. Now it looks like we know what we are doing.	Alan soldering the first part on the real board.	Whoops! We forgot the flux.
So we slobbered on a bunch of flux and reheated it. I think there was some solder wick involved too.	Alan checking the board.	Jeff checking the board.	Peter checking the board.
The first PIC that got soldered down. Now we are getting good.	All the surface mount parts soldered down.	Now it is ready to power up. Oh, we forgot to clip the wires...	Finished board. Except for two capacitors and the jumpers for the encoders.
Wdie angle view.	The testing setup.	After rewiring a serial cable... It works!	Everything went together well and it worked the first time.

Jeff's OSMC project

Probing a surface mount diode
to determine polarity.

Jeff uses a big Weller
solder gun to solder the 4oz
copper on the Open Source
Motor Controller board.
(Didn't work very well. The
old standby 40 watt Radio
Shack iron worked better.)

All the surface mount parts
are in place. And a few
others.

Brynn's new toy

Brynn found this multispeed
gearbox at Axman.

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