My Dad, pictured above, has been awesome about letting me come over and helping me work on the Naomi robot.
The motor came with threaded holes for putting screws into, but none of the hardware stores I visited had screws that were small enough. But the gentleman at The PC Room, a computer repair shop on Gladstone in Ottawa, let me look through his jar of odd screws, and we found some that were the perfect size. He let me have them for free.
Dad and I drilled two holes in the masonite and screwed it to the motor.
Then we mounted the rotating arm on the motor's shaft.
We needed to anchor the ends of the metal dowels somehow. We decided to cut some little blocks of wood and drill holes that were just barely big enough to fit the dowels into. We had to place the holes carefully, because the dowel had to be held high enough off the masonite that the moving part would be free to move without rubbing against the masonite.
We hammered the first dowel into one of the blocks, slipped on the spring and the moving part, and then hammered a block onto the other end.
Then we glued the two blocks to the masonite with Gorilla Glue and clamped them in place for a couple of days to dry. The dowel isn't technically "attached" to anything, but the blocks fit on so tightly and are glued so close together that there's no way it could ever wiggle out. Once the glue was dry, we stuck the second dowel through the moving part, put a spring and two blocks onto it, and glued those blocks to the masonite as well.
Notice how the two springs hold the moving part nicely in equilibrium when the motor is at rest.
At some point in the design process, I'd started referring to this part of the robot as the "Heart of Gold," after the improbability-powered spaceship in The Hitchhiker's Guide to the Galaxy.
The motor is powered by eight AA batteries for a total of twelve volts. Depending on which wires you attach to which leads, the motor can be made to turn in either direction. I discovered that it needed to turn counter-clockwise, because otherwise the moving part bonks into the black screw that holds the rotating arm in place.
And does it work? Behold!
There are no frames missing from this animation -- that's actually how fast the moving part bounces back. I cannot believe that this actually works.
At least, it works so far. Next we'll have to see if I can transfer motion from the Heart of Gold to the other part of the mechanism.