Hello all.
I want to create a board that'll beep/flash a led/etc. when the board's yaw angle faces to north(a digital compass).
and it'd be very nice if I can use the board on a metal surface(no EM interference)
As far as I understand, I need a special sensor/shield for this kind of project. the shields that I could find so far, find only pitch and roll angles but not the yaw angle.
Is there any special shield or something that u guys can suggest?
thanks
Can't help with details, but your subject says you want True north. Compasses and other devices that rely on measuring the magnetic field can only detect magnetic north. They are not the same thing and in fact depending upon where on the globe you do the measurement can be very different (> 15 degrees)
Compass Module - HMC6352 - SEN-07915 - SparkFun Electronics?
But, as wanderson said, you have a small problem.
If you're directly N of 85°54?N 147°00?W? / ?85.9°N 147.0°W, magnetic N will be 180° off.
if the board stays in one fixed location, you might pre-program it with a value when all the sensors are positioned at true north, and then just calculate deltas from this position.
What you will have to adjust for is known as magnetic declination. Here is a brief introduction; Magnetic declination - Wikipedia
And the declination changes not only with your location on the globe, but changes for the same location over time. From the above article; "Magnetic declination varies both from place to place and with the passage of time. As a traveller cruises the east coast of the United States, for example, the declination varies from 20 degrees west (in Maine) to zero (in Florida), to 10 degrees east (in Texas), meaning a compass adjusted at the beginning of the journey would have a true north error of over 30 degrees if not adjusted for the changing declination. In the UK it is one degree 34 minutes west (London), and as the country is quite small that figure is fairly good for the whole of the country. It is reducing, and in about 2050 it will be zero."