This page created 09/22/2001

At the last Science Museum meeting, Bruce Shapiro and I talked about getting an old pick and place robot he has working again. It is a 4-Axis small robot that uses DC servo motors and optical encoders. He doesn't have the controller for it, so he and another guy started building a 4-Channel PID servo controller using JR Kerr PIC-SERVO chips. The guy wired up one channel, and has parts for another channel, but things get pretty spendy quickly, and I guess Bruce didn't want to tak eon the job himself when his buddy stopped working on the project due to lack of time.

Well after looking at this thing for a while, I thought it was just too cute or maybe too ugly to leave lying around unable to move. So I took on the project.

I have a four-channel PID servo controller that uses National Semiconductor LM628 (or maybe LM629) Servo control chips, and some linear servo amplifiers, so I think I can get it working pretty quickly.

But first, it needed to have all the old wiring, extra fittings and brackets removed, and a good scrubbing.

And it needed a name. Orange-bot, Orangie, Hey, it's a girl! Angie... (Bruce can rename her when he re-adopts her later this year)

Click thumbnails for a larger view.

More RSOH

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Angie cleanup

Before: greasy, cluttered, broken.	One axis servo motor, pully and belt.
Some kind of alien connector.	Oh, what a tangled web we weave.
The vertical axis screw and some bizarro limit switches	Under the base. Pneumatics! Yuck.
My son removing another strange limit switch setup.	Hideous wiring rats nest.
Well, all done. And you've GOT to have leftovers!	Oh MAN, that feels better! All cleaned up.
The fourth axis motor installed and no junk wiring.	Under the base again without pneumatics.
The top of a motor showing the encoder connections.

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Next, I took apart one of the motors to see how I could add new wires to the encoder... Motor-guts

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