note: this page is a place holder until a better tutorial is written
Basic Description The digital compass gives measurements based on Earth's magnetic field for robot navigation.
Inside this commonly available MEMS are tiny nano-structures that bend due to
electromagnetic fields. When this MEMS experiences any form of EM field,
the tiny structures bend by an amount which can be electrically detected.
Cheaper digital compasses usually have a resolution of around +/- 5 degrees,
but newer and better ones can detect with a better accuracy.
Availability and Cost Easily available for $30-$100. It is best to buy them with supporting
circuitry included to avoid any interference from bad electrical design.
Power Requirements Minimal, typical logic only.
Tips and Uses
Keep digital compasses far away from anything that emits EM, such as motors, transformers, inductors, etc.
Large conductive items significantly altar magnetic fields (cars, fridges, steel plates, etc.)
Use this device to help for navigation, such as robot race tracks or navigating a maze
because the Earth's magnetic lines of flux "dip" in declination, the compass must remain level for
the readings to be accurate. Some electronic compasses employ a 2-axis gimbal in an attempt to keep
the compass level, but these are problematic in the rough off-road environments
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