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From: ascen@world.std.com (Ascension Technology)
Subject: Re: Bicycle Lean Angle Sensor
Message-ID: <D7JsLD.75p@world.std.com>
Organization: The World Public Access UNIX, Brookline, MA
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Date: Mon, 24 Apr 1995 16:32:01 GMT
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Richard Steven Walz (rstevew@armory.com) wrote:
: >This would indeed work for a perfect bicycle riding on a perfectly
: >flat surface.  I think that most bicycles will require some small
: >steady state offset in the angle of the front tire to overcome factors
: >such as improperly aligned wheels, crown in the road, non-symetrical
: >loading, etc...  
: --------------------------------------
: No. In an increasing turn the delay and the necessary hysteresis to prevent
: over-dithering would let it ride itself right down to the ground, just as a
: human does on a bicycle trying to balance with their eyes shut. Hadn't you
: ever wondered why the blind cannot ride on tracks with sonic beackons to
: guide them? Even blind skiers require a human guide and they have two skis!
: A one legged blind skier would be impossible as well. Not enough data. You
: need the gyro of some variety!
: -Steve

 You may be wrong about not being able to ride with eyes shut.  Balance is
sensed in 3 separate systems in a normal human; the inner ear, visual
cues, and the feedback system between the head and shoulders. Two of the
three are needed to keep balance at any time. 

Maybe the frequency of data from the head/shoulder system is to slow for 
bike riding, or some other factor comes into play. If not, a blind person 
should be able to keep balance on a moving bike.

Regards,
	Steve
