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Unread 11-02-2006, 11:43
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Joe Johnson Joe Johnson is offline
Engineer at Medrobotics
AKA: Dr. Joe
FRC #0088 (TJ2)
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Re: Six-axis positioning sensor suggestions

Quote:
Originally Posted by jgannon
Okay, I read through the data sheet, but I'm not quite sure how this helps with positioning. Could you please explain, Dr. Joe?
accelerometers and angular rate sensors do not give you position either. You need to do some processing to figure things out.

You are going to have to have reduntant sensors to make this work no matter how you slice it.

I would guess that you will have to have wheel encoders plus some other info that will let you know when not to trust your encoders (due to an incline or wheels slipping or whatever). Part of the other info could be provided by this micromag sensor.

It is a complex problem that is sometimes call "sensor fusion."

Your brain does this all the time:
  • Sometimes you use your eyes
  • Sometimes you trust your inner ear
  • Sometimes you trust your sense of touch
  • Sometimes you barf your guts out because your sensors don't agree with eachother and your brain doesn't know WHAT to do ;-)
The MicroMag sensor is not a solution. It may be part of the solution.

Good luck keeping your robot from barfing!

Joe J.
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Last edited by Joe Johnson : 11-02-2006 at 11:46.