Friday, June 27, 2014

Microcontrollers And A Humboldt Laser Harp

I need to find out if laser harps are a fairly common item in Arcata and Humboldt County. If they're not, building one could be a perfect project for the Humboldt Microcontrollers Group.
Laser Harp At Concert

First of all, if you don't know what a laser harp is, we'll turn to Wikipedia, which says:
"A laser harp is an electronic musical instrument and laser lighting display, consisting of several laser beams to be blocked, in analogy with the plucking of the strings of a harp, in order to produce sounds...They have also been used in public art installations...Playing the actual sound is usually handled by connecting the laser harp to a synthesizer, sampler or computer."
The picture at the right shows what one version of a laser harp looks like. The instrument can take many forms.Watching this short video clip will help understand what a laser harp is -- Bucharest Laser Powered Harp. The Bucharest video shows how engaging a laser harp will be for people walking past it. If you want to see someone playing music on a laser harp, watch Tetris Theme on Laser Harp. The Bucharest is a relatively simple version, something that would be a good exercise to build before attempting something like the Tetris laser harp.
Tetris Laser Harp

There are plans available for building a laser harp, many of which use an Arduino. Some plans have to be purchased, while other are free. It looks like a proof of concept might be something along the lines of the Ladyada laser harp exercise (pictures were on the page yesterday, but Flickr was having problems displaying them at the time I uploaded this post). That mini-project or one similar to it lets you learn the basics of sensing the laser beam and programming the microcontroller to respond when the beam is broken.

Once you've been able to generate music by breaking the beam, the next step would be to set up several laser beams so each one can be a different note. I haven't researched laser harps enough to know which would be a better route to go -- building one like the Bucharest laser harp in the short video linked above or building the one whose design is on open-source-energy and is quoted at ~ $100 for the parts and uses an Arduino Uno. It might be
Open-source-energy Laser Harp
quicker to build the open-source-energy one because it has all the plans and Arduino code. If I can recruit enough people to split the cost of the parts, or find a sponsor who wants to cover the whole cost, my vote would be to build the open-source-energy laser harp.

Finally, after we've gotten experience building a multi-beam harp and having it produce decent music, then we could design our own, more like the Bucharest one, that's designed for interaction with people who are walking by. To have the laser harp be interesting looking even if the room isn't totally dark, some people have built in fog machine capabilities so the fog will highlight the lasers. The fog would make the design a lot more complicated, but it might make the laser harp fun to use in a lot more environments.

The next step in deciding whether to move ahead on this is to find out if anyone else in the area is interested in building a laser harp. If I can find another person to work on it with me, we can at least do the proof of concept circuit. Then we'd have to choose a design for the multi-beam harp, price out the bill of materials and come up with a way to cover those costs.

If you're interested in working on a laser harp, send an email to arcatabob (at) gmail {dott} com. We can get together, figure out if we want to start with the Ladyada single beam exercise (if we can get the parts list, circuit designs and Arduino code) or if there's another low cost starter project to learn the basics.

Lasers are always a good thing to have in projects!


No comments:

Post a Comment