AirGuitar02.
A new interface for musical expression.
As the name suggests it uses some guitar like control gestures, such as strumming and fretting, and occasionally thrashing about... The sounds for the prototype version are built in MSP using very crude approximations of Karpus Strong string models. In otherwords im using an exciter (a loud click) and some resonant filters (a combfilter and a few lowpass filters). That sound is then distorted to approximate a hard rock guitar sound. Some day you will get to hear it, or better yet experience a live performance. But for now check out some pix of the controllers and a few brief discriptions of what is going on technically.
The piece of PVC is used in the left hand. It is a essentially a keyer. This keyer is used as the fret/note/chord control for the AirGuitar. Hidden inside this keyer is an XY acellerometer for added gestural madness. The two project box lids tied together are affixed to a belt with velcro or held in the hand. This device controls rhythm and articulation. The flex sensor sticking out of the piece of cut PVC can trigger chord events when flexed fast enough. The large FSR strip controls a palm muting marameter. THe small FSR strip triggers lead/solo events. The XY accellerometer hidden inside this box controls filter parameters in the lead/solo signal path.
I made more small CV to MIDI converter circuits. im using on of the 28 pin, 10 analog input pic chips; 18f2520. These circuits were designed to be modular and low profile. The resistance pull down array and 220Ω resisters for MIDI have put on separate circuits and connected via terminals. This saves me lots of time when testing wireless and serial connections as I dont have to resolder anthything on the main circuit. I only need to change the program the pic is running, and connect different outboard circuitry. The low profile feature, means this circuit and fit in many diffeent situations. The terminals(those blue things)are actually the highest profile part of the circuit, which protects more sensitive components from being squished.
octambic keyer... the dime sized FSRs are the way to go. they feel right under my fingers and are easy for my fingers to find. the little ones are kinda tricky. They have a low profile and much less surface area. My fingers often miss them or dont hit them in the middle well enough to affect the sensor.
An earlier version of the frethand/keyer was wireless... yah. sloooow RF serial is not so good for music. 2400bps means a system latency of 100ms or more when sensing all 8 keys... that just didnt work for me. I'm looking into other highspeed wireless technologies, but for now MIDI is as slow as I can go.
the wireless reciever required its own pic and curcuitry to collect the RF signal and convert it to MIDI. The wireless transmitter is quite small and fit nicely in the end of the piece of PVC.