From: utzoo!decvax!cca!REM@MIT-MC@sri-unix
Newsgroups: net.space
Title: Remote control mining
Article-I.D.: sri-unix.3066
Posted: Thu Sep  2 00:12:36 1982
Received: Thu Sep  9 06:31:45 1982

From: Robert Elton Maas 
    Date: 1 Sep 1982 09:08 PDT
    From: Ciccarelli at PARC-MAXC
    Why the insistence on Earth-based control of the mining machine?
It's simpler to get it working that way. Eventually we want to
automate it. With remote control, we need only solve the problems of
getting the device there and maintaining communication with it. With
automatic control we have to in addition find an algorithm that can
replace a human worker, and debug it. Remember even the Voyager didn't
make its own decisions, we radioed a sequence of commands to it and it
merely executed them by rote. It took days to figure out a change
before we could safely radio it up. We couldn't use interactive
control because (1) too many things had to be done in too short a
time, (2) the radio (speed of light) delay was much more than 3
seconds (more like a half hour each way) making interaction
impossible, (3) motions had to be more precise than a human could do
by servo. On the moon we have plenty of time to stop and retry
something without losing a once-in-a-lifetime chance, only 3-second
total delay, and no need to be especially unclumbsy.
    One possible way of positioning would be for the lander unit to shoot out
    lengths of fine wire which could be several hundred meters long
    and would be energized with a signal which the mining rover could detect.
One more system that can fail. But maybe worth trying the second or
third time.
    1) Can a suitable mining area be located from lunar orbit (i.e. do
    you need to actually sift the sand or can you use remote-sensing
    techniques)? 
    2) Can a payload be set down in that area with suitable
    positioning accuracy? 
    [I think present art would indicate "Yes" on both counts].
Good questions. Is SSI or anybody working on them? Re accurate
locating, a rover to move from landing spot to work spot would help,
as would a navagation system for the Moon similar to the one currently
planned for Earth, allowing travel to within a couple meters of each
other merely by subtracting coordinates and traveling "toward" each
other accordingly. Anybody working on accurate lunar navigation?