Return-path: X-Andrew-Authenticated-as: 32766 Received: from beak.andrew.cmu.edu via trymail for +dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl@andrew.cmu.edu (->+dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl) (->ota+space.digests) ID ; Tue, 9 Jan 90 13:35:40 -0500 (EST) Received: from beak.andrew.cmu.edu via qmail ID ; Thu, 4 Jan 90 20:10:04 -0500 (EST) Message-ID: Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Thu, 4 Jan 90 20:04:28 -0500 (EST) Subject: SPACE Digest V10 #367 SPACE Digest Volume 10 : Issue 367 Today's Topics: Microrovers Ringing in the new millenium Re: SPACE Digest V10 #360 NASA procurement bureaucracy at work Re: Scientific value of Apollo Re: Mars rovers ---------------------------------------------------------------------- Date: Tue, 19 Dec 89 05:11:38 PST From: Ken Harrenstien Subject: Microrovers Cc: KLH@NIC.DDN.MIL I'm a little surprised that during the discussion of Mars rovers, etc, nobody has debated the notion of microrovers or microspacecraft. There were some interesting articles about this in the October 1989 issue of Aerospace America (featuring "Genghis Microrover" on the cover). Briefly, the basic concept is to stamp out thousands (even millions) of cheap tiny probes or "gnat robots" which could then be used with great abandon, relying on their smaller scale and greater numbers to bypass the currently prohibitive requirements for reliability or sophistication. The articles list lots of neat little ideas and applications for these things. The authors were Ross M. Jones and James D. Burke of JPL (microspacecraft) plus Rodney A. Brooks and Anita M. Flynn of the MIT A.I. Lab (microrovers). What makes this a little more interesting than the usual theoretical brainstorming is the illustrations of actual MIT mobile robot testbeds, the smallest weighing 50g. It would be nice if someone familiar with these areas of research could post additional details... --Ken ------- ------------------------------ Date: Tue, 19 Dec 89 12:25:18 EST From: JC%RMC.BITNET@vma.cc.cmu.edu Subject: Ringing in the new millenium You folks all seem to be missing the wonderful opportunity presenting itself here. Instead of arguing over which New Year's eve to have a gigantic party you should arrive at the obvious compromise: celebrate BOTH years. --------------------------------------------------------------------------- Pascal keeps your hands tied. C gives you enough rope to hang yourself. John Coughlin Net: JC@RMC.BITNET Vox: 613-541-6439 Fax: 613-547-3053 ------------------------------ Date: Tue, 19 Dec 89 12:43 EST From: CLASSICAL WORK AND QUANTAL RESULTS Subject: Re: SPACE Digest V10 #360 X-Envelope-To: space+@andrew.cmu.EDU cancel sub sub cancel it was worth a try ------------------------------ Date: Tue 19 Dec 89 11:00:08-PST From: Jay Glass Subject: NASA procurement bureaucracy at work Mail-System-Version: Want to get NASA to move quicker and produce more results? Try reforming the federal procurement system. Case in point: in order to get an otherwise-free upgrade of Microsoft Word 3.x to 4.0, I needed to write a full purchase order for the $5.50 handling fee. Worse yet, it was returned to me two weeks later because I didn't attach a "purchase request review checklist" and an "acquisition-data processing management review summary." The paperwork is the same as that required for a $65K purchase of real-time control s/w for my lab, and comparable to that for a $250K university research grant. Aargh! I'm sure that other NASA employees could describe similar horror stories. Jay Glass glass@pluto.arc.nasa.gov ------- ------------------------------ Date: 20 Dec 89 15:44:07 GMT From: zaphod.mps.ohio-state.edu!swrinde!cs.utexas.edu!jarvis.csri.toronto.edu!utgpu!utzoo!kcarroll@tut.cis.ohio-state.edu (Kieran A. Carroll) Subject: Re: Scientific value of Apollo steve@groucho.ucar.edu (Steve Emmerson) writes: > > henry@utzoo.uucp (Henry Spencer) writes [referring to John McKernan's > assertion that it is "empirically evident" that the unmanned program > is more cost-effective than the manned program]: > > >My point is precisely that it's not. Remember, I am talking about getting > >the *same* results -- volume and diversity of samples, surface experiments > >emplaced, cores drilled, precision landings at pre-chosen sites, etc. -- > >not the far smaller and simpler missions undertaken by all unmanned landers > >to date. > > ... I believe it would be a mistake to attempt to > compare (assuming for the moment that one could ;-) manned and unmanned > exploration using as the judgement criteria the detailed and immediate > goals and results of the manned activities. It would be better, in my > opinion, to refer to a higher level of endevour, such as the quantity > and quality of the increase in our knowledge, or the potential for > further advancement in this area. > This is a good point, one that underlies (I think) much of the manned-vs-unmanned infighting. Henry's point is that a set of unmanned missions, designed to accomplish the same things that Apollo accomplished, might well have cost as much as Apollo did; thus, citing the great expense of Apollo when arguing that manned missions are inherently much more expensive than unmanned ones makes for a poor argument. Your point is that a less-expensive suite of unmanned missions might have accomplished the "higher-level" goals of Apollo, just as well as did the expensive manned ones. Of course, this depends on the "high-level goals" that are involved. There are at least three sets of high-level goals that were satisfied by Apollo. The goals that motivated Kennedy et al. to pay for Apollo was (to quote a previous poster) "geo-political muscle-flexing", or striving for national prestige through highly visible technical accomplishments, in order to win support for America's ideology over the Soviet one. The goals that were being pursued by the engineers that "sold" Apollo to the administration (Von Braun and friends, and their American proteges) were exploration of the moon, and development of the infrastructure with which space stations, lunar bases, manned Mars missions and the like could be supported. In addition, there were space scientists involved in Apollo (it's not clear to me whether they were among the original players, or were enlisted after the program had been "sold", in order to provide additional justification for the program; or perhaps just because adding space science wouldn't cost much more, and so why not allow the scientists aboard?). Their goal was to carry out research of various forms -- into the nature of the moon, mostly. As many have argued, there's no way that an unmanned exploration program could have satisfied the first set of goals in the same way that Apollo did. Pictures sent back by robots probes make a splash, then disappear without a trace (except among the space addicts, and a few scientists). After all, the USSR was the first to send robot probes to the moon, but "the-man-in-the-street" sure doesn't remember it (and wouldn't care, if you told him). How many people do you think still remember, on the other hand, that "an American was the first person to walk on the moon"? Today we tend to dismiss the first set of goals as having been unimportant, a waste of time and money to try to accomplish. However, they seem to have been pretty significant at the time -- I suppose that a couple of more decades of lessening international tensions has changed the outlook of people in the US (not to mention things like Vietnam). Thus, people these days seem to act as if the second and third sets of goals were the actual drivers of the program. Not only that, but the manned-spaceflight enthusiasts (myself included) judge the second set as being the "truly important" goals, with the third set being less significant; Van Allen and company, on the other hand, discount the second set of goals >entirely<, and tend to proclaim the third set as the only reason for having gone to the moon. Boy, it's no wonder people are getting nasty in their arguments! Manned-vs-unmanned is arguing the wrong question; more important is the question of "What should we be trying to accomplish in space?" Once we've sorted that out, the areas in which manned and unmanned spaceflight can contribute will be quite obvious. -- Kieran A. Carroll @ U of Toronto Aerospace Institute uunet!attcan!utzoo!kcarroll kcarroll@zoo.toronto.edu ------------------------------ Date: 19 Dec 89 07:50:41 GMT From: zephyr.ens.tek.com!tektronix!percy!parsely!bucket!leonard@uunet.uu.net (Leonard Erickson) Subject: Re: Mars rovers stolfi@jumbo.dec.com (Jorge Stolfi) writes: >I find it amazing that people can argue so vehemently that teleoperated >rovers Can't Possibly Work, as if the Russian Lunokhod rover had never >existed. Sure, it was only the Moon, not Mars; but are we to conclude >that 10 years from now the US will not be able to even *try* improving >on what the Russians did 20 years ago? But this is *not* the same thing. Engineers seem fairly confident that teleoperated equipment can be done over the Earth-Moon distance with it's 2-second lag. And much better than poor old Lunokhod. But the difference between 2 seconds and 1200seconds is a quite different matter. Even if you assume that the difficulty goes up linearly with the lag you are talking about something that is *at a minimum* 600 times harder! Personally, I suspect it goes up with the square. Try this. All you have to do is tell the manipulator arm to pick up a rock sample a foot or so more or less in front of the rover. So you tell it to extend the arm out 12 inches. 20 minutes later you get to find out what your next positioning command is... Sure, you can add sensor to let the arm track in on an object. But if you do THEN IT ISN'T TELEOPERATED!! It's at least semi-autonomous. And you still have to figure out what to do if it is homing in on the *wrong* rock... -- Leonard Erickson ...!tektronix!reed!percival!bucket!leonard CIS: [70465,203] "I'm all in favor of keeping dangerous weapons out of the hands of fools. Let's start with typewriters." -- Solomon Short ------------------------------ End of SPACE Digest V10 #367 *******************