This week, I ordered sample PIC chips from microchip.com. They supply up to a 3 count each of 5 different types of PIC chip, which is plenty for my purposes. Although my order hasn’t arrived yet, Joan Soler kindly let me borrow a few different types.
After playing with them for two days straight, the PIC is a bit more inconvenient than the BX-24 (with which I’m very comfortable). There is no pseudo-multitasking as in the BX. This is a real drag since almost every interesting application has multiple tasks running at once. But by timing tasks carefully, this limitation can be worked around. And I can always buy 5 PIC chips for the price of one BX and get multitasking that way ;)
I also ordered samples of accelerometers and digital potentiometers from Analog Devices, although I don’t have any use for these for the Metal Petals as far as my current designs go. The accelerometers could be handy in case I decide to detect movement of the tin snips and hammer in the performer’s hands.
I’m still searching for free samples of capacitive sensors and specs on the different sensors available. My experiences with QProx digital capacitive sensors in the past have been less than stellar – their response time, sensitivity, and ease of use leave much to be desired. Still, they’ll probably be the best bet for sensing the manipulation of the metal.
Unfortunately, my goal is not to sense the manipulations by the performer so much as the final position and shape of the metal when at rest. Capacitance will be affected by the performer’s presence and proximity, which will have to be averaged out. For this reason, I think the sensors in tandem with video tracking will provide the most information on both movement and final shape of the piece.
As a backup, I may try sensing the resistance of the metal by running a current through it. As the shape is bent and cut, the resistance is likely to change perhaps more reliably than the capacitance.
The assigned reading, “Contexts of Collaborative Musical Experiences” by Tina Blaine and Sidney Fels somehow seemed to be another regurgitation of the “low entry fee, no ceiling to virtuosity” mantra with a few broad classifications of collaborative musical experience thrown in for good form.