I was recently rooting around on an old computer when I came across some files relating to projects I put together back in the undergraduate and graduate days. I thought they might be better served posted somewhere than gathering dust, so here we go!
In the summer of 2003, three enterprising individuals by the names of Rick Corbett, Jim Prestia and Pierre Baillargeon undertook a project of awesome proportions. You see, they wanted to graduate from college, yet before them stood a requirement to design and build senior project. It started innocently enough, with a dot matrix printer no one loved anymore.
It didn’t take long for the dot matrix printer to be stripped down, leaving only a stepper motor and drive system.
Great. We had a stepper motor with no documentation or drive circuitry. What do we do now?! Well, we hooked it up to an OOPic-R microcontroller, some transistors and a device that would display the signals being sent to the stepper motor.
Once the motion control circuitry and programming was established, we had to determine how to electro-mechanically blow air into and suck air out of a harmonica. One short trip to Sports Authority later and the solution was in hand. A pair of air pumps used to inflate inflatable mattresses would solve the problem, all we had to do was reverse the air hose attachment point on one of the pumps and we would have one pump to blow air and one to suck air. The two pumps and associated electronics were then unceremoniously stuffed into a metal box.
A custom mouthpiece was fabricated to direct the air at the optimal point in front of the harmonica and final assembly began. Pumps, microcontroller, control electronics, air solenoids, a control keypad and display LED were all connected and mounted onto a piece expertly painted plywood.
The final remaining item was to tie it all together with usable software. This was accomplished with a Windows application that came with two predefined songs and allowed users to load their own songs from a text file.
That’s all great, right? But did it work? It sure did!
