I'm not sure if this is the right place to post this, but here goes.
I already have the ping))) ultrasonic range finder, but i was in my local electronics shop today and saw these boards labeled "Ultrasonic Rangefider" for $2, so i picked one up just to try it out. Anyway, I cant find any documentation on it anywhere and was just curious if anybody has come across them or might know anything about them. There appears to be both a single ultrasonic sensor, as well as two IR senors. There are 4 pins, 5v, gnd, and I.R. and U.S. Just for fun i hooked it up to my arduino and used the old 3 pin Ping sketch from the examples, but to no surprise it didnt work.
The only thing written on is Virtual Ink Corp., OPCOP6 94V-O, 500-0031 REV ____. That's it. Google came up with nothing.
Google told me that Virtual Ink made interactive whiteboard systems. Could be they were using a combination of IR and ultrasonics to track a marker. I'd start by applying power to +5 and Gnd and see what comes out the other two wires. Hiss at it to try and trigger the ultrasonic sensor. Shine a remote control at it to see if it reacts to IR input.
Yep. It's a combination of IR and Ultrasound that determines the position of an intelligent marker on the board. There need to be two of these devices in two corners of the whiteboard to determine the location of the pen.
I couldn't get anything out of the ultrasonic, but the ir worked fine with a remote. That's fine, a $2 ir sensor works.
Perhaps the ultrasonic is "send only"'. To track the marker they might send out ultrasonic pulses and measure the time between the send and IR return.
I'm sitting here wtíth an eBeam system. In the pens there are a PIC12C671 microcontroller, 4 IR-transmitters and one ultrasound receiver.
The pens seem to work this way. They received the ultrasonic pings, triangulate where the receivers are, in accordance to the pen, then transmits the pens position along with it's color. It's the same for the eraser, it just tells the computer to erase.