This is my creation for our first assignment in Networked Objects. It’s a shaker using lentil beans, a plastic container, vibration sensors, and an arduino mini + breadboard. Shaking the device triggers an animation of my macbook’s desktop shaking. It’s just an 11 frame loop of screenshots I altered to make it look like it’s shaking. The desktop itself does not shake. The effect is pretty good when using Processing’s “present” runtime mode.
Most of the issues I encountered were related to the vibration sensors I purchased from Parallax.com. These are plastic piezoelectric sensors. I am using 5.1v zener diodes to filter the voltage spikes generated by the piezos. A 1MΩ resistor pulls the input pin to ground, giving me a nice range to work with. It tooks a while (and a lot of bugging Tim Twyllman) to figure out how to get useful values out of the sensors, but I think the final result is prett good.
This was also my first experience with an Arduino Mini. It’s an amazing little device, but I did not own a USB-to-serial breakout board and had to borrow one. The positive is that the whole device fits on a small breadboard that is adhered to the container’s top…but it sure doesn’t leave a lot of room to insall components. It may be hard to see from the video, but the side with the analog inputs is a mess of zener diodes and resistors. I had to be creative with positioning the connections, as well as figuring out good places to connect the sensors to ground. But in the end, it works pretty well!