In my work I have been using a Vectronix Digital Magnetic Compass (DMC) for several years. We choose this component for our project because it was widely recognized as the best magnetic system in the world. Fully calibrated in a non magnetically hostile environment, it can provide a heading to 0.1 degrees. Now a pretty big price tag comes with this accuracy and it was well outside my hobbyist budget. So I wrote the folks at Vectronix an email and they have kindly decided to provide me a unit in return for a logo on the robot and some video or other media.
So this is my first blog entry to meet my obligation.
I am very excited to use the Vectronix DMC in that I have years of experience with this part. I know how accurate it is. Just as an example, we had to replace many of the stainless steel fasteners in our product because the grade of stainless had free iron molecules that would distort the field. Just walking across a room 15 feet away with a small belt buckle would cause the magnetometer to swing away.
So if the unit is that sensitive how am I going to use it in an RC car with a permanent magnet motor generating a large magnetic field? And what about all the nuts and bolts I might use? And what about the fields generated by current loops on my circuit boards? All good questions. But I do know that the company that makes MuMetal (magnetic shielding) is just down the street. Worst comes to worst, I am sure I can get some design guidance from them.
This week I got called out of town on an emergency field service call to a fix a system that was under test with our customer. Spend three days on 4 hours sleep a night. But when I got home a 9-DOF IMU, an RC servo mux, and other various parts were waiting for me. Life is good.