( h o w . t o . m a k e ) a sensor and visualize its output

gershon dublon
responsive environments group :: MIT media lab

fun with sensors

This week we learned about sensors. The assignment was to connect a sensor to a microcontroller and visualize its output on a PC. I was interested in building a bend sensor, and as it turned out, Hannah's work was the first result on google for "DIY bend sensor." Her idea is simple, cheap, and elegant (and it works!): two pieces of velostat, an inexpensive, resistive material found in anti-static bags, are sandwiched between flexible conductors. Bending applies pressure to the velostat layers, effectively lowering the impedance across the conductors (the same sensor can be used as a force-sensitive resistor).

I used Neil's cad.py to adapt a board design Laurel was working on. Parameterized, procedural circuit design can be very slow-going for the inexperienced user.

The board wouldn't power up at first, a problem that I quickly traced to the regulator. Unforatunately, I tore off a piece of the trace removing the part. Reluctant to mill and stuff another board, I made the following work of art:

And miraculously, it worked!

mas863 2009