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From: rwmurphr@wildcat.ecn.uoknor.edu (Robert W Murphree)
Subject: Re: Modeling Slip, Mobile Robotics, Kinematics, Simulation
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Date: Fri, 20 Nov 1992 05:32:20 GMT
References: <1e8eknINNdn6@clover.csv.warwick.ac.uk> <1992Nov17.144824.26839@aio.jsc.nasa.gov> <56478@dime.cs.umass.edu>
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connolly@rabbit.cs.umass.edu (Christopher Ian Connolly) writes:

>In article <1992Nov17.144824.26839@aio.jsc.nasa.gov> graves@drseus.jsc.nasa.gov (Philip Graves) writes:
>>In general, you can only get a qualitative idea of what might happen
>>from any model of this type. It is impossible to find the perfect model
>>because the friction depends on a plethora of factors, including 
>>everything from temperature to how long it has been since the floor 
>>was mopped and waxed.

>We use Denning robots and are faced with a similar nightmare.  One of
>the things we're working on at the moment involves using visual homing
>techniques to essentially recalibrate the robot at various points in
>the environment, and coupling that with motion planning.  I'd have to
>agree with the other posters in that the best we can hope for (at
>least in the case of the Denning) is some bound on the slippage, and
>to take advantage of that bound when we can.

Doesn't slip occur more often at times of high acceleration and
fast turning? Could you have one braket for low acceleration and
slow turning and another bracket for high acceleration and fast
turning?  I guess, realistically, it varies so much with the surface
that its not worth doing.  Plus, what if you run over a grease spot
or some spilled liquid?
