Newsgroups: comp.robotics
Path: brunix!uunet!usc!cs.utexas.edu!qt.cs.utexas.edu!news.Brown.EDU!noc.near.net!gateway!miki!wpns
From: wpns@miki.pictel.com (Willie Smith)
Subject: Re: How to Explore Mars
Message-ID: <1993Jan11.170735.20763@miki.pictel.com>
Organization: PictureTel Corporation
References: <HAGERMAN.93Jan7224103@rx7.ece.cmu.edu> <1993Jan8.230824.12476@pasteur.Berkeley.EDU> <GERRY.93Jan8231255@onion.cmu.edu>
Date: Mon, 11 Jan 1993 17:07:35 GMT
Lines: 40

In article <GERRY.93Jan8231255@onion.cmu.edu> 
	gerry@cmu.edu (Gerry Roston) writes:
>system reliability.  This is not true because one can not assume a
>priori that the failure modes are independent.  That is, if the robots
>are identical, and one of them fails in a particulr manner, this
>implies that the others will also be prone to that particular failure
>mode.

Unless the 'failure modes' are on the order of "I've fallen and I
can't get up!".  This also assumes all of the small machines are
identical and will haev the same failure mechanisms.  Multiple,
co-operative machines are more likely to be able to help each other
out of tight spots.  Unfortunately, multiple machines also seems to
imply smaller ones.

>From a technical viewpoint, the major drawback to small robots in
>telemetry.

This one is trivial to solve, the mother ship that lands the smaller
robots has the large antennas, high power amplifiers, and even a lot
of the 'brains' of the multiple smaller rovers in it's vicinity.

>These micro rovers would be incapable of meaningful scientific
>exploration. 

I think everyone is setting up straw robots for the other side's
viewpoint.  Possible rover sizes range from the CMU Ambler and the
Army's (future?) teleoperated bulldozers all the way down to the MIT
microbots and Drexler's nanomachines.  My own feeling is that a small
number (say 3 to 6) of medium sized (say 3-4 feet on a side) vehicles
can be very useful, but then that's the size vehicle I built for my
Simulated Lunar Teloperations projects, and the _major_ size
constraint on that was that it had to fit in the back of a VW Golf!

Willie Smith
wpns@pictel.com
-- 
Willie Smith     wpns@pictel.com     N1JBJ@amsat.org
"That's the wonderful thing about crayons, they can take
you to more places than a starship."  Guinan - STNG
