Building it
How it lights up
I love acrylic so that was my material of choice. Since I wanted it to be art and thus be wall mounted the objective was to make it flat. I wanted it to light up but didn't want unsightly bulbs behind it so I decided to mount LED's into the inside edges of each section.
How it senses
Because I did not want to have unsightly bulky components behind the acrylic I decided to use transparent conductive plastic as touch pads. These are sandwiched between the coloured front sheets and a backing sheet. The sensors thus become almost invisible, and the instrument then becomes more mysterious about its workings.
An intricate custom made array of parts connect the six pads to an Arduino running the CapSense library. The pads are thus effectively capacitance sensors and extremely sensitive even from a few inches to the movement of a hand or body. The device thus operates a bit like a theremin. It is also extremely sensitive to a plasma ball, quite why this is I am unsure.
Build photos
Data output
Data from the sensors is streamed via the USB port to a computer. The objective of visualising this data in the beginning was in an attempt, to help me write the person recognition program, this however wasn't achieved but I did get it to control the direction of a robot by swiping different directions over the sensors.
I made a number of simple graphs using processing to monitor the activity of the pads and discovered that it sometimes picks up some random spikes of energy that appeared to have systematic patterns. Activity also varied between rooms and between day and night. I became intrigued about what the data might sound like, so I decided to add sound output.
Sound output
Now at this time I was quite new to Arduino and examples of sound were comparable to an 8 Bit Chip Tune quality, I was looking for something more advanced, so I opted to convert the data to MIDI music format. Since any wired connection to Prosopo was sensitive to the capacitive detection pads I opted to add a Bluetooth connection which sends data to the receiving device called Midi Acker