In Reply to: Re: Design of a circuit that can measure angle to the wall? posted by Ray on 01/23/03 at 8:35 PM:
I need a way for a device to figure out what the angle to the wall is. Say I have a camera facing the wall at an unknown angle. I want the device (let's just say it's attached to the camera) to tell me that I'm 37 degrees from the wall.
The way the magnet works is if I initially calibrate a zero angle, then it can tell me any other angle. Let's just say my current module is reading back 68 degrees (relative to the north pole), but I visually determine that I am facing the wall directly. I push a button which saves 68 degrees as my 0 degree reference point. Now, if I move 15 degrees over (keep in mind I don't know how much I move), the device will read 83 degrees. Therefore my camera will now know that it's 15 degrees away from it's original spot. Now, anywhere I move, the circuit will be able to tell me exactly how many degrees I am relative to my initial spot. That's how the magnet works.
With ultrasound or optics, I guess I just want to direct a signal at a wall and have a sensor read back the angle of reflection?? As I mentioned, I need something small and cheap that can automatically determine the current angle it is at relative to a wall in front of it. The magnetic solution works with a single initial calibration, is cheap, and is small, but too prone to interference.