Resonance Experiements

At first I was hoping I wouldn’t need a resonator to increase the volume of the vibrating strings. Unfortunately, the strings are barely audible on their own.


I next tried putting some found objects on the end of the string. This was still barely audible.


I then decided I really needed to study instrument acoustics a bit. In a instrument like a guitar, it seems that the main thing that vibrates is the bridge. This is a piece that the strings go across just before attaching to the guitar:

The bridge then vibrates the front side of the guitar. This pushes the air molecules inside the guitar that then bounce off the back side of the guitar.

I decided to try a small version of this. This was louder, and audible, but still not loud enough.



I’m working on a much larger version now, that more closely matches the project sketch. I’m constructing it so I can try different materials out for siding on the same frame. I will also be trying different sized bridges as well.



Arduino magnet wire wrapping assitant

I’m wrapping my own magnetic coils for a project I’m working on and I need to wrap each coil 600 times. To help keep track of the count I made an assistant out of an Arduino and a photo resistor. In this test I wrap black tape around the chuck on a drill and then put a strip of white tape over it. Shining a light from underneath reflects off the white strip as it rotates and shines more brightly into the photocell. The Arduino uses this change in brightness to count how many rotations the drill makes and when it gets to the right amount an LED turns on. In the video example the light turns on after 10 rotations. Code is included below.