On Aug 31, 10:38 pm, hellocatfood <bv3...@gmail.com
> I'd certainly like to start building this! Looking at the materials
> list do we have any those?
I have 5 low-cost micro red laser modules from Odicforce:
They need to be driven by a current limited supply (a resistor will do
to start), and an Aduino can drive it. It needs to be kept below 1mW
so that eyesight isn't easily damaged.
According to stuff on the net, less than 1mW is 'okay' because a
normal person blinks quickly enough to avoid eye damage.
This all seemed a bit dodgy to me, so I got red LASER SAFETY GOGGLES:
If green LASERs are used, the guy who runs Odicforce said they should
have Infrared filters too; he said green LASERs emit a lot of
Infrared, which they eye does not respond to by blinking, so be
careful. Odicforce sells green LASER SAFETY GOGGLES too:
The laser Harp in the article uses six Sharp GP2D12 or GP2D120 IR
This is actually the 'guts' of the instrument. It measures distance
to, for example, your hands. This works whether or not their are
The lasers are really showing you where to put your hands, and the
range measuring sensors do all of the work to figure out how far away
your hand is.
The cheapest places to buy those sensors that I've found are (USA) at
about $8 + P&P etc:
UK (£8.40 inc P&P):
Six would be about £50. A bit expensive for my school projects :-(
Those sensors look nice to use, they produce an analogue voltage to
represent distance. That would be fed into an Arduino analogue pin,
and a sketch reads that, and decides what note to play.I keep meaning
to try them for robotics. At least one of the micromouse guys have
One of the articles explains how to use an Arduino to generate MIDI
events, so, I imagine almost any midi instrument can be used.
I would suggest starting with a one-string "Theramin". Then all of the
basic electronics, and playing music gets solved using only one of
those distance-measuring sensors.
Once something is working, there'd be lots of room for experimenting
with different sensors, and ways to control the notes.
I am thinking a nifty solution might be a single laser scanned across
an arc using my 'mechanical TV' mechanism set up to work as a camera.