Physical Computing: Stupid Pet Trick

With the knowledge acquired thus far, we were enlisted to create a "Stupid Pet Trick" for Physical Computing.  In short, this meant creating a novel, simple device that enlisted out knowledge of analog and digital inputs and outputs in a hopefully entertaining.  In my case, I decided to take the assignment quite literally, and design an interactive cat toy.

The toy consists of two pieces:  a tennis ball on a spring, and a laser pointer mounted on a servo.  Once the program is initialized, the servo is driven by data coming from a flex sensor embedded in the tennis ball.  In this way, the play of one cat (with the tennis ball), will drive the entertainment of another (with the laser pointer).  In short, it's a low maintenance way to have the animals keep each other busy.

I embedded the tennis ball and spring in a wooden platform for stability, and fed a flex sensor up into the spring.  That way, when the spring bent, so did the flex sensor.  I routed a wire conduit out of the wood so that the wires would be hidden, and then sealed them in with a glue gun.

The laser mounted on the servo was a bit more of a "hack job", employing twist ties and a free Flaming Lips laser pointer.  However, in the end it worked out quite well, with the on/off button controlled by another twist tie.

The circuit itself was actually quite simple, needing only one input and one output for the flex sensor and servo, respectively.  What's more, it worked quite nicely with the spring easily driving the servo.  

 Perhaps the only drawback was that as a sketch of a device, I kept the two pieces quite close together.  This resulted in the two components being far too close together to allow for "real world" testing without the two pieces distracting the animals from "their" side of the toy.