Posted by Alison Lewis | tagged: MIDI, infrared, Alison, circuitry, music

When we met the Word family, we knew we'd have to come up with something special. Every member of this family has incredible musical talent, not just Lewis (who's hard at work on his hip hop masterpiece).

We wanted to build something that would let the family make music at any moment‚ even with just a wave of their hands.

This is a pretty simple Infrared Harp. The sensors work like on/off switches to trigger various sounds when they are plugged into your computer's music program. With the MidiTron you can use any type of analog or digital input device, from temperature sensors to regular switches, to trigger your sounds. Get creative, it's really fun to think about all the things you could play!

MATERIALS:

* Epoxy
* 8 - 10 Infrared Sensors
* MidiTron
* 22- 24 gauge wire in red, black, and yellow
* Needle nose pliers
* MIDI to USB converter
* Two 4 - 6' aluminum u- channels
* Two 4 - 6' of 2 x 4 wood
* Large SPST On/Off Switch
* Wood Screws
* Drill
* Stepper drill bit for drilling through metal
* Zip ties (small)
* Zip tie mounts
* Wire Butt Connectors (small 26 - 24)
* Crimper for the connectors
* Multimeter for testing connections
* 9V 300mA power supply with connector
* Solderless Breadboard
* Box of jumper wires
* Jewelry screwdriver set

SOFTWARE:

* Music software like Garage Band
* MidiTron Software
* USB Driver software

The USB software driver should come with the MIDI to USB converter.

STEP 1: Test the Infrared Sensors

Attach the wires to each of the IR sensors. Snap the red, black, and yellow wire into the connector and attach it to the sensor. Avoid any direct light on the sensors.

Place the wires from the sensors into the corresponding channels of the breadboard. Use jumper wires to connect the yellow wires to the MidiTron. Now connect the power supply to the MidiTron. Then, using jumper wires, connect the MidiTron to the vertical channel of your breadboard.

STEP 2: Set up your MidiTron

Connect the MIDI to USB converter to your MidiTron and to your computer. Open the MidiTron program. Set the inputs to "Digital In". Now run your hand over the sensors. You'll know it's working if you see a little "X" appear in the boxes. Now set up the note scale you want to use. We started with middle C.

STEP 3: Prepare the U-Channel

Measure the location of your sensors on your U-channel. Space them out evenly. Pre-drill the u-channel for attachment. Then, with your stepper drill bit, drill holes into the u-channel at a 45-degree angle. The angle will let you reach into the u-channel to drill later. Do this with the bottom channel as well.

STEP 4: Complete the wiring

Using epoxy, glue each IR sensor into place on the interior back of the U-channel. Daisy chain all the plus-wires together by using the wire butt connectors. Do the same with the minus-wires of the IR sensors. Then, cut a length of wire to connect to each of the data cables of the IR Sensors. Now fasten each data wire to one of the wires you just cut.

Use zip ties to tuck the wires away, but leave enough slack so they don't pull out of the IR sensors. Use your multi-meter to test the connections. Once it's working, disconnect the wires.

STEP 5: Anchor harp and MidiTron to the wall

Paint your 2x4's. Now locate the studs in the wall and attach the two-by-fours. When you attach the bottom 2x4 be sure its distance is farther than the longest measurement of your IR sensors. You don't want the bottom bar setting off the sensors automatically.

Screw in your U-channel with the IR sensors facing downward to the top 2x4. Screw in the bottom U-channel to the bottom 2x4. Now anchor your Miditron to the wall. We hid ours under a tambourine. Then cut and strip your wires, so they reach the MidiTron, Leave slack so they don't pull out of the sensors.

Infrared sensors know exactly where your hands are, and you can digitize any kind of music.

So now you can start composing your off-the-wall symphony!