It's been a hectic and kind of rough couple weeks with work travel, workload, school, and family/personal stuff going on... But I've managed to squeeze in a few things.
First, someone was kind enough to make two broken inkjet printers available on Denver Freecycle. Turns out there are three motors in each, of varying sizes. Lots of gears, too. And a rotary encoder. And some rubber rollers that maybe can be turned into wheels. I am hoping that I can use this stuff in robots including Squeaky the Record Cleaning Robot.
On that topic, Squeaky hasn't progressed much. I've experimented with using the vacuum to lift off cleaning fluid and gunk from the record but the suction is high enough that it wants to grab onto the record so I am pondering some options on how to retain the suction without lifting the record off the platter.
I also took apart a 3-in-one stereo system and salvaged a transformer and several small motors (two for the tape deck and two for the 3-disc CD changer). Maybe something to use for a tiny robot or two. The vacuum fluorescent display appears damaged but there's another in a DVD player that I'd like to play with as the status display for Squeaky.
Sunday, October 19, 2008
Tuesday, September 16, 2008
Squeaky: Chassis Done
Squeaky < prev | next >
Time is running out for robotics. My last class of the year started last night and the spectre of impending homework, reading, projects... Meanwhile my shelves are now packed with hundreds of recently acquired, filthy records pining away for a good record cleaning machi--err, record cleaning robot. Squeaky. As you know I'm kind of winging it on this one.
Squeaky is going to use a motor/sprocket/tooth-belt assembly from a bread machine with an idler wheel attached, so the entire assembly needs to pivot. Idler wheel pressure will be controlled by a spring. The previous incarnation led to a rather floppy assembly due to play in the single bronze bushing.
The new version uses a 3/8" threaded rod as the axle, with two bronze bushings to control wobble. I started with a 3/4" plywood base (leftmost picture below) of 13"x15" based on some mockup measurements. The base houses the lower bushing. A hole with chamfer (middle picture) makes it easier to hammer the bushing into place. A wood tower houses the topmost bushing and the threaded rod goes through both (rightmost picture below).
Lock nuts will cinch against the thrust surfaces of the bushings and hold the threaded rod and bushings in place and allow for end play adjustment.
With the pivoting rod in place, all that's needed is the serrated lock nuts to clamp on either side of the motor platform and now the pivoting drive assembly is held securely with nearly no wobble.
In the picture (above right) despite the dreadful fuzziness, you can make out the lock nut on the bottom and the serrated lock nut above it, holding up the bottom of the motor assembly. Another neat feature of this arrangement is that the height of the motor can be adjusted precisely.
The upper platform is 3/4" plywood, same dimensions, into which I installed the turntable spindle assembly, and cut a hole through which the idler wheel will protrude. It's not pretty but it works and it won't be visible during normal operation.
The top platform is supported by four 1" square dowels screwed into place form top and bottom (below left). Also not pretty. But, I do plan to dress this thing up once I get the details worked out. I had to make a few minor modifications but in the end, it seems to work, there's room for the vacuum, for the fluid reservoir, etc. The mechanism seems a lot tighter and more precise than my earlier mock up.
Regarding the electronics... I accidentally blew up the transformer that came with the bread maker but I was able to salvage an entire power supply including fuse, switch, transformer out of the junk linear tracking turntable I got for free and it all works beautifully with my homebrew bridge rectifier (above right).
Squeaky < prev | next >
Time is running out for robotics. My last class of the year started last night and the spectre of impending homework, reading, projects... Meanwhile my shelves are now packed with hundreds of recently acquired, filthy records pining away for a good record cleaning machi--err, record cleaning robot. Squeaky. As you know I'm kind of winging it on this one.
Squeaky is going to use a motor/sprocket/tooth-belt assembly from a bread machine with an idler wheel attached, so the entire assembly needs to pivot. Idler wheel pressure will be controlled by a spring. The previous incarnation led to a rather floppy assembly due to play in the single bronze bushing.
The new version uses a 3/8" threaded rod as the axle, with two bronze bushings to control wobble. I started with a 3/4" plywood base (leftmost picture below) of 13"x15" based on some mockup measurements. The base houses the lower bushing. A hole with chamfer (middle picture) makes it easier to hammer the bushing into place. A wood tower houses the topmost bushing and the threaded rod goes through both (rightmost picture below).
Lock nuts will cinch against the thrust surfaces of the bushings and hold the threaded rod and bushings in place and allow for end play adjustment.
With the pivoting rod in place, all that's needed is the serrated lock nuts to clamp on either side of the motor platform and now the pivoting drive assembly is held securely with nearly no wobble.
In the picture (above right) despite the dreadful fuzziness, you can make out the lock nut on the bottom and the serrated lock nut above it, holding up the bottom of the motor assembly. Another neat feature of this arrangement is that the height of the motor can be adjusted precisely.
The upper platform is 3/4" plywood, same dimensions, into which I installed the turntable spindle assembly, and cut a hole through which the idler wheel will protrude. It's not pretty but it works and it won't be visible during normal operation.
The top platform is supported by four 1" square dowels screwed into place form top and bottom (below left). Also not pretty. But, I do plan to dress this thing up once I get the details worked out. I had to make a few minor modifications but in the end, it seems to work, there's room for the vacuum, for the fluid reservoir, etc. The mechanism seems a lot tighter and more precise than my earlier mock up.
Regarding the electronics... I accidentally blew up the transformer that came with the bread maker but I was able to salvage an entire power supply including fuse, switch, transformer out of the junk linear tracking turntable I got for free and it all works beautifully with my homebrew bridge rectifier (above right).
Squeaky < prev | next >
Saturday, September 13, 2008
Esquire E-Ink Magazine Cover
I'm sure you've heard about the Esquire E-Ink cover? Everyone's blogging about it so I guess I have to, too. Picked one up today.The thing doesn 't do enough to impress my wife :) but I think it is pretty neat. Better, it appears to be hackable according to Make. It's got a PIC processor, 5-pin programming header, and two e-ink flexible screens that apparently can be switched. I notice the development kits over at e-ink cost $1500-3000 so... no plans to create my own custom robot displays until I win the lottery... I wonder if you can do anything with just the processor...
Subscribe to:
Posts (Atom)