My first new media project was the Digital Wind Chime — it would detect contacts between the ‘chimes’ using magnetic reed switches and produce digital music. I’d like to make an updated version, so I’ve been doing some preliminary brainstorming about how it could work and what it could look like.
One disadvantage of using magnetic reed switches was that they were magnets, and as they’d be attracted to each other, they’d have an effect on the free movement of the chimes. Another disadvantage with my original method was that they’d need to contact in relatively specific locations in order to be triggered.
The solution I’m currently pursuing uses accelerometers. These detect acceleration on 2 or 3 axis in space (2 should be sufficient for my needs) and I can use these not only to detect contact between different chimes (by recording sharp changes in g-forces), but I could potentially also detect subtle movements that don’t necessarily involve physical contact with other chimes. This would allow me to make a more dynamic digital wind chime. Each chime would house an accelerometer.
With the original prototype, I had used a hacked keyboard PCB. Because it’s a digital device, it either detected on or off — no in between. Accelerometers can provide analog signals and I’ll be using an Arduino to read these. I can then have the Arduino board send these figures to custom software running on a PC, which could then translate them into music. Subtle movements could trigger a more ambient sound while sudden jerks (contact between chimes) could trigger a more pronounced sound — I could also potentially differentiate between the X and Y axis to get more variation in sound output. The Arduino has a limited number of analog input pins, so it’ll be a challenge getting multiple hooked up to a single Arduino. I may need to make some compromises — perhaps only tracking a single axis of movement for each accelerator/chime, or using analog accelerators for some chimes and digital accelerometers for others.
As for the physical design, I’ve only barely started to throw around some ideas. Because my chimes don’t actually need to have acoustic qualities, I have a lot of flexibility and I’d prefer to have the device appear very different than a typical wind chime. I’ve been looking at designs for hanging mobiles and other hanging sculptures for inspiration.
This is one prototype design I’ve sketched in Maya. The tubular components would be painted PVC pipe with colored LED’s inside to give visual feedback. I could potentially employ the color fading code I was using in the LED array project. I’m not satisfied with this design though, and I’ll post other design sketches I make and any progress I make on the blog.
