the first evening with my first robot

It's hard to stop giggling long enough to write this. I've been playing with a robot that I've been piecing together over the past
few weeks. It's far too much fun. I'm such a robot virgin.
This is just a remotely-controlled wheelchair right now. Don't imagine that I think it's a full-fledged intelligent being. It has possibilities though. (I'm most interested in using it for "telepresence.")
I started with a Quickie G-424 wheelchair.     http://www.allegromedical.com/wheelchairs/power_chairs/quickie/quickie_g424.P163737 It has a power tilt seat and a digital QTRONIX interface joystick. I disconnected those and bought an extra power harness (cable) to connect to a RoboteQ AZ2550 motor controller.     http://roboteq.com/ax25koview.shtml
Once I had bare wires, I took the harness and controller to a local electrical shop (B&M). They crimped on 50 and 175 amp plugs. Today I got everything together and just looked at it for a long time. It seemed so simple! Everything was just "plug-and- play". Batteries to harness, motors to harness, harness to controller, controller to computer (RS-232). RoboteQ even provides all of the RS-232 commands I'd need. (Where was the soldering? I couldn't even find bare wires to spark together?)
Everything was just sitting there staring at me, waiting to go. I did't believe that it would be that easy. Surely the motors would explode because I mistakenly assumed they weren't brushless. And I was betting that I wouldn't be able to control the hardware without a few calls to RoboteQ.
Finally I just decided to try the smoke test. I connected a motor and began firing commands at it through Kermit. "!A01" Nope, not even a full echo. Hmmm...documentation...looking...ah! It needs 9600,e,7,1. Wow! It's been a long time since I've used that.
O.k., look through Kermit...set parity, set stop-bit, ... Try again. Nope. But it echos now. Must need more power. "!A40" Doh! There it goes! Woo hoo!
From there it was a matter of hooking up the other motor, getting a Python serial module and writing some code. I put my newer Toughbook in the wheelchair seat with a small 802.11b antenna and did the programming on my other Toughbook from the relative warmth of the garage doorway. (See the videos for why I want Toughbooks around this thing.)
It's fun writing code that immediately *does* something. It also makes debugging more interesting when a 7-bit carryover error results in something that weighs more than I do suddenly reversing directions - at full speed! (24 volts at ~50 amps can really turn the wheels.)
My wife came to see what was causing the uncontrolled giggles and maniacal laughter. (The dogs, OTOH, stayed hunkered down in the bedroom.) I pulled out my camera to capture the moment.     http://lairds.us/tmp/robot /     (temporary location)
Oh, such fun I'm having!
In case anyone feels like providing pointers, I'm looking for obstruction sensors, an arm capable of opening doors, and a 24VDC power supply for MiniITX systems.
--kyler
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