Newsgroups: comp.robotics
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From: abrown@hpcvcec.cv.hp.com (Allen Brown)
Subject: Re: A sense of balance
Message-ID: <1993Feb4.012757.6384@hpcvca.cv.hp.com>
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Date: Thu, 4 Feb 1993 01:27:57 GMT
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> This is the big problem with things like the helicopter robots, or
> rockets or things of that nature.  "Which way is up"?  Anything
> cheap (<$100,000) has too much drift to integrate it for very long.
> The way NASA and the military get around the problem is to buy
> millions dollar gyroscopes that you can integrate long enough so
> that you can get to the next place you want to go in short enough
> time to recalibrate before you get lost.
> -Olaf

I think you are making this more difficult that it needs to be.  Small
airplanes have a gyro indicating up.  They are not very expensive.
They are weighted to autocenter over time.  They work because the
airplane spend most of its time in "up is normal" position.  If you
invert your airplane long enough the gyro will drift to indicate the
ground is up.

That is good enough for most robots.  They will not be spending much
time upside-down or sideways.

Think of it as a gyro stabilized joystick.  :-)
--
  Allen C. Brown  abrown@cv.hp.com or hplabs!hpcvca!abrown or "Hey you!"
      Not representing my employer.
    There is one thing I can promise you about the outerspace program:
    Your tax dollars will go farther. --- Wernher von Braun
