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Richard Trigaux
There was hot debates about wether Moon exploration is to be achieved with manned crews or with unmanned robots. I think the mixed concept exposed here can use both, or be successful even with only one if the other fails.

First, only activities directly linked to lunar ground are useful on this ground: any other would require much less energy in free space. And things like telescopes are better in free space than fixed to a dusty and vibrating ground.

At first, a fixed crewed base on the Moon is useless: once the local geology explored, appears the need to move. (the only exception would be a large drilling project, which would require a fixed crewed base. But we are still far of this. And I don't speak of mining, a pure ideological view if we consider the cost of bringing back materials on Earth)

So we need to move. In order to be able to visit a significant number of targets.

A rover.

A rover like Oppy and Spirit. But much larger, several tons like the LEM, see 20 or 30 tons.

There was on another thread on this forum (I don't remember where) an extensive discution about an automatic remote controlled Moon rover, its requirements and inconveniences. Large solar panels, which need to be cleaned. Full lab for isotope, cristallography and chemical analysis. Even gas analysis (rocks often contain gas bubbles very interesting to study). Such a lab could be miniaturized, but it would remain very complicated to operate and maintain, some said it would be even impossible to made it remote-controled and reliable enough.

Considering all this, I though of a mixed mission concept which would be interesting:
-a large automated rover
-several crewed missions using a smaller LEM to service it.


In remote control, the rover would be able to
-rove on large distances on the Moon (some even suggested to "race the sun" so that to alway have solar energy)
-take samples and make simple analysis.


Manned visits could:
-come on spots of special interest.
-take samples and manipulate them for more complete analysis.
-maintain the rover, bring new instruments or replace damaged parts.
-take back to Earth choosen samples of special interest for most complete analysis.


Concretely, the manned encounters could work that way:
-the manned landing module lands on a spot of interest, while the rover comes along to rendez-vous.
-the rover has a kind or skip or lorry, so that it can haul and carry the manned return stage. The crew can stay into this return stage, or have a larger cabin into the rover. From here they can perform EVA on the ground or for maintaining the rover.
-in this configuration, the rover can stay on the spot or proceed to other places, carying the return stage and the crew.
-when the human presence is no longer required, of if there is an accident, the return stage is fired and it goes directly to Earth (this is a bit more difficut than with the former LEMs, which had only to come back in lunar orbit).


One of the major advantage is that the manned visits don't need to bring each time an heavy luggage of rover, power resources and instruments: once landed, the rover can remain available for many missions.


So the whole thing works like the Hubble space telescope, most of the time in remote control, but with manned service missions. It just has more manned missions, and not just for maintainance. But the number of manned visits can be tailored according to needs and to budgets, from many to zero. Even in the later case the rover still has its interest.


The concept is even politics-friendly, allowing "ideological" manned presence to be really useful, and opposed conceptions (manned/unmanned) to collaborate rather than excluding each other. We can even imagine that he rover (US made, I guess...) could receive manned missions of Europe, Russia or other forms of collaborations.


It would not be interesting to rebuilt a series of the old Saturn V rockets, but I think it would not be difficult to rebuilt a series of a modernized version, using already existing components such as shuttle boosters, reservoirs or engines, together with modern electronics.

A nightmarish automation problem would be a complex automatized sample analysis lab able to stand the comparizon with a real Earth lab. Concretelly the belly of the rover would be organized around a handling "charriot" moving on rails, and able to carry samples from any instrument to any other (analysers, saws, containers...) with the proper orientation and force. The instruments would be mounted on racks, and there would be enough space for an astronaut to operate safely between the instruments, and eventually easily replace any of them, including the charriot. (rails being passive, could be considered reliable). The only real (but really bad) problem in there would be dust.
djellison
QUOTE (Richard Trigaux @ Feb 12 2006, 08:12 PM) *
I think it would not be difficult to rebuilt a series of a modernized version, using already existing components such as shuttle boosters, reservoirs or engines, together with modern electronics.


That's exactly what is being planned -
http://www.freemars.org/mnfan/MarsSociety/...ce/100_2889.jpg
http://images.spaceref.com/news/2005/cev.28.l.jpg

Doug
BruceMoomaw
The flaw with Richard's proposal is that -- thank to the very short radio-signal time delay between Earth and moon -- you can run an automated rover almost as well directly from Earth, without the stupendous additional cost of putting humans on the Moon. You just have to do things slightly more slowly.

In the case of other planets, it's a different matter. At the Mars Strategic Roadmap meeting back in January 2005, a NASA spokesman told us that any manned expedition to Mars is going to take a radically different form from what most people think -- instead of having astronauts clumbering around on the surface in spacesuits (which was difficult on the Moon, and will be even harder in Mars' higher gravity), most of the exploration efforts will be done using robots remote-controlled from the central manned Mars base, or from inside the cabins of nearby pressurized manned rovers.

And then there's the variation on this, driven by the problem that any manned Mars lander will instantly and very seriously contaminate the very biological evidence which is virtually the only possible scientific goal that could justify something as vastly expensive as a manned Mars trip -- namely, the idea that any manned Mars ship will remain in Mars orbit (or on one of the moons), running a network of sterilized robots and unmanned sample-return vehicles by radio. This idea is becoming increasingly popular, assuming that we ever get to Mars at all.
Bob Shaw
A manned Mars flight to Mars orbit only is both cheap and quite doable in terms of current - indeed elderly - technology. Add better propulsion, a centrifuge module, and some shovels - then set up a base on one of the moons, dig in against the radiation, and get to work. As has been discussed elsewhere on UMSF, building a manned Mars lander which can take off again is going to be a bitch - so why bother, until the transport technology has reached Berlin airlift proportions!

Bob Shaw
Phil Stooke
What are you doing up at this time of night, Bob?

I think Bruce is dead right about this. Many people seriously underestimate the difficulty of a human Mars landing. Approaches like Zubrin's are very seductive, but the reality will be horribly difficult. Personally, I think a base on one of the moons is by far the best approach for scientific studies of Mars during this century. I don't expect to see footsteps on Mars in my lifetime... which I'm hoping will take me into the second quarter of this century!

Phil
Bob Shaw
Phil:

I'm allowed up late once a month, for the full Moon.

As for the human exploration of Mars, the joy of a Martian base on one of the moons is that it more-or-less kick-starts the asteroid mining scenario, and *that* could have serious long-term implications for our whole species. The only problem, though, is that we keep agreeing with Bruce, who now will have to go forth and prosletise in his unique manner, and we'll eventually get stuck with the thing being named MarsBase Moomaw in his memory. I demand that the waste-processing works be named the Proxmire Module!

Bob Shaw
dvandorn
Bob, I agree entirely with *anything* that will kick-start asteroid exploration/exploitation. Asteroids are a lot easier to get to than planets (in terms of landing on them or docking to them, anyway), they contain tons and tons of raw materials, and may provide resources to us back here on Earth once some of our more popular resources (like soft iron, for which terrestrial sources are nearly depleted) get so scarce here that importing them from asteroids becomes financially feasible.

I want to see manned asteroid explorations in my lifetime, and I'd like to see *mining* companies get involved. I want to see us start to figure out how to do mining operations in microgravity!

-the other Doug
Richard Trigaux
QUOTE (BruceMoomaw @ Feb 13 2006, 12:56 AM) *
The flaw with Richard's proposal is that -- thank to the very short radio-signal time delay between Earth and moon -- you can run an automated rover almost as well directly from Earth, without the stupendous additional cost of putting humans on the Moon. You just have to do things slightly more slowly.


I agree with that point. But:

-"certain" politicians will anyway and whatever WANT humans on the Moon. And humans on the Moon at only a given spot are of little use. But if their presence is made ubiquitous by the help of a rover, it is much more useful.

-Yes we know to make a remote controled rover. But what about doing real sample analysis, like isotopic analysis, radioactive datation, polarized light crystals examination, X-ray diffusion? Of course we can design such a remote-controlled system on the Moon, but it would be very unreliable, with nearby all the time one of these instruments in failure. So the human presence can be useful, even in a few percent of the time, simply to maintain the system, replace an instrument, remove a stone stuck in the way or clean a camera lens. It the Hubble-style, where human presence, useless 99.9% of the time, was very useful 0.1% of the time, to better the mission (and even to save it).



By the way we could better the concept:

-one of the "instruments" in the lab could be a small sample return shuttle. There could even be several. When one one of them is full, it is fired back to Earth.

-the instrument bay in the lab has no bottom wall. The rails are close to the bottom, on the side walls, and the instruments above. The chariot presents the samples upward toward the instruments. If anything goes wrong, the sample falls on the lunar ground, and there is no further harm.

-A LEM type vehicle is rather narrow and it don't allow for a prolonged presence. We can accept this inconvenience to make the rover lighter. But we can also add to the rover a larger cabin, with an airlock able to connect to the LEM, allowing for a more prolonged stay.

-We can give the rover an overall flat form, so that it could accomodate for adding modules, at need or permanently, such as the above cabin, or the manned return stage. Starting from this simple design, we can decide later to add the cabin, or not.

One of the limitations of such a large Moon vehicule is solar power (Fusion power is still a future technology, and a RTG would not give enough power for long drives). So it needs large solar arrays. This could quickly make it large, cumbersome and unstable. The idea would be to make it drag a series of cariages, like a train.
BruceMoomaw
Well, yes, if we're going to insist on sending humans pointlessly back to the Moon, we might as well at least greatly extend their effective range of exploration by setting down some long-range rovers to explore the surface and return samples to the human base for more detailed study. But one can also achieve the latter goal by landing a few unmanned sample-return landers on the surface and having the rovers -- after excursions of hundreds of km -- rendezvous with the SR landers on the surface and deliver a selection of samples to them for return to Earth. That is, a lunar version of exactly the same scheme now favored for Mars sample return. Indeed, NASA's scientists worked out the design for such a mission back around 1970 -- and concluded that an unmanned program consisting of two rovers, two SR landers, and a lunar polar orbiter could produce a total science return vastly bigger than that of the entire Apollo program, for just a few billion dollars.

Aviation Week also briefly mentioned back in early 1972 that NASA had toyed with the idea of designing the rover on Apollo 17 so that, after the manned mission was over, it could be driven a very long distance along the surface from Earth with an instrument package. This, however, would have very hard to implement at that stage -- and it would probably have forced elimination of most of the other science instruments on the mission. (It would probably have been easier to implement Harrison Schmitt's idea for a farside Apollo 17 landing!) I know no other details.
dvandorn
QUOTE (BruceMoomaw @ Feb 13 2006, 03:34 AM) *
...Indeed, NASA's scientists worked out the design for such a mission back around 1970 -- and concluded that an unmanned program consisting of two rovers, two SR landers, and a lunar polar orbiter could produce a total science return vastly bigger than that of the entire Apollo program, for just a few billion dollars....

Yes, and NASA's scientists worked out back in the late '90s a design for a mission that would have pieces of Mars back on Earth right now, for only a half-billion dollars.

So much for studies by NASA scientists.

Seriously, unmanned sample return had not been accomplished at the time that 1970 study was done, and since then it has been done to the tune of only a few kg of rock and soil, at most. I'm not saying it couldn't have been done -- I'm saying that the odds of some mechanism becoming jammed by the ubiquitous lunar dust, ruining the mission, were high.

You can't even admit that Apollo ended up as a scientific windfall for exo-geologists, far moreso than *any* unmanned program of the time could have returned, can you, Bruce?

Frankly, this sing-song "there is and has never been a single good reason to put men into space" rant of yours is getting a little old, at least with me. And, again frankly, I don't want to live in a world where all humans are told to take a seat on the sidelines and leave the *real* exploring to the robots. That road leads to the end of *all* significant exploration, IMNSHO.

-the other Doug
ljk4-1
What's a space agency for?
---

The newly-released 2007 NASA budget proposal, among other events,
has touched off another debate on the relative importance of robotic
space science and human space exploration. Jeff Foust examines the
arguments and suggests NASA needs to work harder to build a
compelling case for both.

http://www.thespacereview.com/article/557/1

Lunar platinum and alcohol fuel cells
---

One problem with hydrogen fuel cells is the difficulty in obtaining
hydrogen. William White argues that an alternative, alcohol-based
fuel cells, may stimulate significant demand for platinum and hence
spur efforts to look for it on the Moon.

http://www.thespacereview.com/article/555/1

The new humans vs. robots debate: introducing the FH Prize
---

What's the problem with people who advocate using robots rather than
humans to explore space? Simple, says Michael Huang: they're human.

http://www.thespacereview.com/article/554/1
Richard Trigaux
QUOTE (BruceMoomaw @ Feb 13 2006, 10:34 AM) *
Aviation Week also briefly mentioned back in early 1972 that NASA had toyed with the idea of designing the rover on Apollo 17 so that, after the manned mission was over, it could be driven a very long distance along the surface from Earth with an instrument package. This, however, would have very hard to implement at that stage -- and it would probably have forced elimination of most of the other science instruments on the mission. (It would probably have been easier to implement Harrison Schmitt's idea for a farside Apollo 17 landing!) I know no other details.


An argument toward unmanned robots is that, in the Apollo era, robots were fledgeling. Today we are much better, and robots could do today things we were unable to do at that time. But "my" man-serviced rover could also punctually help robots on the ground, for instance to repair or upgrade them.
Richard Trigaux
Thank you for your arguments exchanges, Bruce and Dvandorn Other Doug.


But, you know, I am a guy of the 21th century, nourished from nearby childhood with logic, spirituality, non-dual mind, Yin Yang dialectics... So I am neither of the two opinions "pro-manned space flight" or "con-manned spaceflight".


Your arguments, Bruce, make sense: perhaps it would have be much cheaper to launch two, see three Hubble telescopes, rather than to maintain one at the tremendous cost of the whole shuttle program. If we think a minimum, there are in space many "ideological developments" (understand: projects which MUST be pursued whatever their cost and utility) and a more rational management would allow much more science return with a much lesser cost. Furthermore the tremendous development of robots and remote control makes than humans are less and less useful in space, and they will be soon completely useless. Not to speak of the alway present risk of accidents.



But, you see, I am not insensitive to the point raised by Dvandorn, and I can resist to quote what I would have said myself:
QUOTE (dvandorn @ Feb 13 2006, 02:19 PM) *
... And, again frankly, I don't want to live in a world where all humans are told to take a seat on the sidelines and leave the *real* exploring to the robots. That road leads to the end of *all* significant
-the other Doug

Yes, there is more in space exploration than just gathering science data. It is a philosophical and aesthetic challenge: to leave our Earth craddle and see stars from another perspective! To SEE and FEEL! What do you think if 18th-19th century explorers had brough only science data from Hawaï or Tahiti? Without a word of sensual beaches, marvelous flowers and strange people? Yes there are no sensual beaches on Mars, and we shall have to be satisfied with the accound of only some traveller. But this human contact, even scarse, is very important I think.
So Kenedy was not wrong when he set the goal to an human journey to the Moon: this feat struck the imagination of every people in the world when 1 billion more science bits would not. Certainly the basic motive was futile (showing that capitalism was better than communism!!!) and today Bush's motives for man on Mars are probably not better. But the idea of pursuing a manned presence in space is very significant for us all.




So what to do? The cost of a manned visit to the Moon would really be much bigger than the cost of eliminating misery and hunger in the world? I think not. In a world where so many people are ready to give tens or hundred bucks a year for humanitarian purpose or catastrophe relief, they will readily give one or two more for a manned mission. Certainly the ratio of manned budget versus robot budget will vary widely according to superficial political considerations. But if we are in a period wher it is high, so why not to use it wisely.

To use it correctly, with both science an philosophical/aesthetic utility.

My project, I said, is politics-friendly. This means that, even once started, it can accomodate with any variation of the manned budget, from many (many servicing missions, contacts with other manned ground missions...) to zero manned presence (entirely robotic rover). It don't constrain us into a costy program we cannot abandon once started, like the ISS.

Ah, to smell the moon dust and martian wet!
dvandorn
I like your overall concept, Richard, and I think something like that will end up being the cornerstone of our eventual manned Mars exploration strategy.

However, in addition to the many advantages you mention (immediate no-lag control of robots, ability to explore on more human timescales, etc.), there will be a more important and useful application for a Phobos or Deimos base.

At such an orbital base will reside Mission Control for the manned landing and surface operations.

We've seen just how well lunar exploration worked when we had a Mission Control back in Houston watching out for the technical details, allowing the surface crews to concentrate on the exploring. The Apollo J missions were a testament to just how effective such a combination can be.

So, for manned Mars surface operations, you can outfit a Flight Control Center within your orbital base, and have the orbital crew serve as flight controllers for the landing and surface ops. In fact, a majority of the people staffing the orbital base would likely have more primary concerns over telepresence robot ops and over manned surface ops than they would with any of the orbital base's functions, be they maintenance, engineering or scientific.

We could fly a set of manned Mars orbital missions which start developing an infrastructure on either Deimos or Phobos within the next 25 years. By the third or fourth orbital expedition, we could permanently man the Phobos/Deimos station, switching out crews every 18 months or so. Ten years of that kind of orbital ops, and we'll be *more* than ready to tackle manned surface ops.

Unfortunately, even with this relatively slow, simple, we-have-the-technology plan, we're looking at about 2040 for the first manned surface ops... *sigh*... Be a hell of a way to celebrate my 85th birthday, though!

-the other Doug
BruceMoomaw
QUOTE (dvandorn @ Feb 13 2006, 01:19 PM) *
Seriously, unmanned sample return had not been accomplished at the time that 1970 study was done, and since then it has been done to the tune of only a few kg of rock and soil, at most. I'm not saying it couldn't have been done -- I'm saying that the odds of some mechanism becoming jammed by the ubiquitous lunar dust, ruining the mission, were high.

You can't even admit that Apollo ended up as a scientific windfall for exo-geologists, far more so than *any* unmanned program of the time could have returned, can you, Bruce?

Frankly, this sing-song "there is and has never been a single good reason to put men into space" rant of yours is getting a little old, at least with me. And, again frankly, I don't want to live in a world where all humans are told to take a seat on the sidelines and leave the *real* exploring to the robots. That road leads to the end of *all* significant exploration, IMNSHO.

-the other Doug


In reply:

(1) The astronauts themselves had serious trouble with dust. If it had led to a spacesuit failure or an PLSS failure, we would have something a wee bit more serious than the loss of a cheply replaceable unmanned rover. (By the way, by 1970 we already had undersea robots performing very complex underwater tasks successfully. Remember the Palomares H-bomb, and the Nimbus 3 RTGs? And the Moon is a much more congenial environment for robots than the deep sea.)

(2) Just "a few kg" of rock and soil would have been more scientifically valuable overall than the half-ton the astronauts brought back, if it been collected from regions covering hundreds of km across the Moon.

(3) If you think that "real exploration" will come to an end when robots allow us to take our eyes and minds to new locations rather than the difficulty and expense of lugging our bodies along, provide some evidence rather than just saying it, please. Lewis and Clark would have jumped at the opportunity to let their fingers do the walking through the western territories; Columbus would have done likewise. But they didn't have our technology. At some point, of course, new techonologies WILL make it worthwhile to send humans into space, just as new technology eventually made it worthwhile to return to the South Pole. If we do it before then, we will simply be seriously slowing down the progress of human exploration as a whole -- something the FY 2007 NASA budget makes excruciatingly clear.

As for the "scientific windfall" of the Apollo Program, let me add a footnote to my second point by quoting Norman Horowitz on the subject in the March 1990 issue of "The Sciences" (the magazine of the National Academy of Sciences), on Bruce Murray's arguments for a manned deep-space program:

"How plausible is all this? Not very, if one considers the assumptions on which it is based. One assumption is that Apollo was good for science and that therefore a manned Mars mission will also be good. The other is tht robotic science cannot reawaken the country's interest in space; allegedly, that can only be done by astronauts. With regard to the first, it is important to remember what scientists thought of the Apollo program when it existed. They detested it. They criticized it for the same reasons the shuttle is criticized today: it consumed funds that should have been spent on space science, and its claims of being a scientific program were unjustified.

"This neglected bit of history is recounted in 'Beyond the Atmosphere: The early Years of Space Science', by Homer E. Newell, who was associate administrator of NASA until his retirement in 1973. Newell reminds us that Philip Abelson, editor of 'Science' magazine, thundered at the Apollo program, arguing that it was not worth the effort and expense and that much more could be achieved at far less cost with unmanned spacecraft. At one point Abelson polled some 200 scientists o the question and reported their overwhelming agreement with his viewpoint. Newell also recalls the criticisms of Eugene Shoemaker, a member of the U.S. Geological Survey who spent years on the Apollo project developing instruments for lunar exploration and training astronauts in field geology. But before Apollo ended, Shoemaker excoriated the program for its inattention to the needs and interests of science and for wasting opportunities to accomplish more lunar science than it did. These criticism and those of other scientists finally resulted in the inclusion of a geologist, Harrison Schmitt, on the last Apollo flight.

"Murray's second assumption -- that only human involvement can interest Americans in further explorations of Mars -- is also questionable. The cost alone of sending humans would surely cool the enthusiasm opf many citizens and congressmen who thought they favored the venture. In contrast, an advanced robotic mission would cost one or two percent as much. Further, the new technology in robotics and artificial intelligence that would be generated by such a mission would be useful for mcountless tasks at home, so the mission would help pay for itself. One of the arguments advanced by Murray and others who favor sending men to Mars is that man has explored every place within his reach -- Earth, Earth orbit, the moon -- and now it is time to go to Mars. This whimsy has become a central tenet of the new Martian dream. The truth is, however, that much of our own planet -- the bottom of the seas -- is still unexplored by man. It has always been too difficult a place for humans. Now it can be done robotically. Manned exploration of the unknown world was necessary in the 15th century, because there was no other way to do it. But in our time the only reaon to send humans on voyages for which robots are better suited is to entertain the television audience.

"The American public has repeatedly shown its interest in the question of life on Mars and the look of faraway places. Most recently that interest was demonstrated in the popular resposne to the adventures of Voyager 2. It is also seen in the eager public anticipation of the launch of the Hubble Space Telescope. Given such evidence, is it unreasonable to suppose that Americans may decide they prefer robotic missions to Mars for the foreseeable future? Anything is possible, once they have reflected on the costs of a manned mission in dollars and in lives. (Judging from our Apollo and Shuttle experiences, a loss of life is probable.) Of course the public must be told why scientists think Mars is an interesting place to study: What can we learn from Mars that we cannot learn at home? Why does it seem possible that life existed on Mars in the past, and how do we propose to search for evidence of it? Why are robots, controlled by artificial intelligence (and ultimately by humans on Earth), better suited than astronauts for pursuing these questions? Let us hope that the nation will not have to waste many billions of dollars and a crew or two before it changes the direction in which it is currently headed."

You don't have to completely follow Horowitz' belief that robots will ALWAYS be better at exploring worlds beyond the Moon than humans are to agree with his main argument. The switchover to robotic exploration of the deep sea has not "ended that era of exploration"; it has tremendously accelerated it. Unless we can come up with concrete reasons to pump gargantuan amounts of money into manned deep space expeditions in the near future -- and we can't -- their only possible purpose, as Horowitz said, is as public entertainment. And the public is consistently telling the pollsters that they aren't willing to spend more than a total of "a few billion dollars" of their tax money for manned lunar and Mars expeditions -- which is to say that they don't think they're worth doing at all for entertainment value. But they MIGHT be willing to spend that same "few billion dollars" on really interesting unmanned space exploration, in which case it actually WOULD get some results.
dvandorn
Very, very good reply, Bruce. Thank you -- this is more the kind of spirited discourse this subject needs.

Now, for a few counter-points and expressions of appreciation... smile.gif

QUOTE (BruceMoomaw @ Feb 13 2006, 05:14 PM) *
At some point, of course, new techonologies WILL make it worthwhile to send humans into space, just as new technology eventually made it worthwhile to return to the South Pole. If we do it before then, we will simply be seriously slowing down the progress of human exploration as a whole -- something the FY 2007 NASA budget makes excruciatingly clear.


I'm very glad to hear that first statement. I actually think we're more in agreement than not, overall, Bruce -- I don't think it's necessary for us to be spending billions on manned lunar or Martian operations within the next 20 years, when we're on the verge of making some significant breakthroughs in so many areas that will make it *far* faster and easier to get around the solar system than it is now. For instance, I think we're going to be hearing a lot more about Franklin Chiang-Diaz's plasma drive in the near future.

However -- and here we part company, I think -- I *truly* believe that we have to stay in the manned spaceflight business in order to be able to take advantage of these new technologies as they come on line.

I am convinced that developing a CEV that can be used as a multi-purpose crew delivery system to both present and future mission-dedicated spacecraft is a good idea, a good investment, a necessary maintenance of American manned spaceflight capability, and a justified use of NASA's resources.

I personally think that Shuttle ops should be limited to completing the ISS and performing one last Hubble servicing flight. The NASA planners are saying that will require 29 more flights. I assume they know better than I do how much it will require... though I have to say, I think it could be done in less. And the current (dare I say cowardly?) reluctance of NASA to fly a vehicle that is safer than any version of it they have ever flown before, drawing good money after bad without getting *any* result out of it, is the basis of yet another discussion... *sigh*...

The failure of NASA to be able to maintain any kind of consistent funding levels for a well-planned unmanned exploration program is not, in my opinion, simply a case of the manned program "eating" the unmanned program. What we are seeing is a political failure, not an administrative failure. For good and solid administrative *and* political reasons, the manned and unmanned spaceflight directorates were set up separately 'way back when in the '50s, precisely so that funding pressures from a potentially floundering manned program would not result in the rape of the unmanned exploration programs. The political failure took place gradually, over the course of both Democratic and Republican administrations, but the multi-center, separate-accounting days of NASA have been over for some time now. And with a single administrative steering committee responsible for *all* NASA programs, and responsible for the "sharing of the pie" all 'round the town, we have now been put in the position where political pressure to "make us some space heroes" has become responsible for cutbacks in unquestionably worthwhile programs.

As with any political failure, it can be reversed, over time. The concept of presenting to Congress separate funding requests from different NASA centers, each with its own set of justifications, can be brought back. I mean, there are constituencies within almost every other federal agency -- we *can* get it back to where the unmanned and manned constituencies are able to argue their own cases and be dealt with as separate entities, pursuing related but separate goals.

That, IMHO, is the only reasonable course to try and navigate -- get JPL and APL and Huntsville and Houston out there, pitching their own programs and getting their own separate budgets. Such a process would raise the level of discourse, and result in a better-educated set of lawmakers.

QUOTE (BruceMoomaw @ Feb 13 2006, 05:14 PM) *
You don't have to completely follow Horowitz' belief that robots will ALWAYS be better at exploring worlds beyond the Moon than humans are to agree with his main argument. The switchover to robotic exploration of the deep sea has not "ended that era of exploration"; it has tremendously accelerated it. Unless we can come up with concrete reasons to pump gargantuan amounts of money into manned deep space expeditions in the near future -- and we can't -- their only possible purpose, as Horowitz said, is as public entertainment. And the public is consistently telling the pollsters that they aren't willing to spend more than a total of "a few billion dollars" of their tax money for manned lunar and Mars expeditions -- which is to say that they don't think they're worth doing at all for entertainment value. But they MIGHT be willing to spend that same "few billion dollars" on really interesting unmanned space exploration, in which case it actually WOULD get some results.

Yes, a lot of deep-sea investigation is being done by robots. But, even though robots can do the job far more safely and effectively, and can get into so many small nooks and crannies, why do people spend millions of dollars to arrange their own manned dives down to the wreck of the Titanic?

In that case, just sending our senses there isn't enough. As a people, as a culture, we have to *keep* sending people down to that wreck. Even though it costs a fairly ridiculous amount of money to do so, and is a somewhat risky thing to do. And even though such continued visits are destroying the wreckage.

Even though we don't have to.

But, as near as I can tell, solely because we can.

As for those pesky polls -- you know what they say: there are lies, damned lies, and statistics. If you look more closely at those same polls, those same people believe that NASA's budget is larger than that of the Department of Health and Human Services, that it amounts to well more than $100 billion a year, and that they believe that somehow all that money ends up getting shot into space, and not spent on salaries, resources, support and maintenance, etc., etc., etc....

Give me a poll of informed Americans, and I'll take it a little more seriously.

-the other Doug
BruceMoomaw
"Yes, a lot of deep-sea investigation is being done by robots. But, even though robots can do the job far more safely and effectively, and can get into so many small nooks and crannies, why do people spend millions of dollars to arrange their own manned dives down to the wreck of the Titanic?"

Using their own money. And THAT is the center of the whole issue. If gazillionnaires want to use their own cash to go into space, or dive to the Titanic, or try to set a new world record for how many live hornets they can glue to their head without increasing their hat size, while I can think of (to put it mildly) more socially responsible uses for their moolah, after they've paid their taxes they are perfectly free to use what'e left for those activities. But they do NOT have the right to use taxpayer money for those purposes.

As for "a poll of informed Americans", the informed Americans -- consistently -- take a dimmer view of manned space exploration, because (as I keep saying) it's far less cost-effective at gaining any concrete benefits for humanity. Which means that the only justification for it is entertainment, under whatever name you want to call it. And that means that the taxpayers, who are supposed to be the ones being entertained, have every right to directly decide how much they want to pay for that particular form of entertainment -- a right they do not have with any kind of spending that actually requires specialized knowledge as to its cost-effectiveness.

One final note: since I seem to have a perverse talent for hijacking every thread on this site for the purpose of diatribes against manned spacelight, I think it might be wise to set up a thread specifically to discuss the preferability of manned versus unmanned spaceflight down in the "Policy" section, and plant all future discussions on the subject there.
David
QUOTE (BruceMoomaw @ Feb 14 2006, 02:51 AM) *
One final note: since I seem to have a perverse talent for hijacking every thread on this site for the purpose of diatribes against manned spacelight, I think it might be wise to set up a thread specifically to discuss the preferability of manned versus unmanned spaceflight down in the "Policy" section, and plant all future discussions on the subject there.


That only works if you can keep from talking about MSF on the other threads... yes, I know. It's like scratching an itch. tongue.gif
djellison
QUOTE (BruceMoomaw @ Feb 14 2006, 02:51 AM) *
One final note: since I seem to have a perverse talent for hijacking every thread on this site for the purpose of diatribes against manned spacelight, I think it might be wise to set up a thread specifically to discuss the preferability of manned versus unmanned spaceflight down in the "Policy" section, and plant all future discussions on the subject there.


If you want a ranting place ( and you've done plenty of it here, and formerly elsewhere ) then get a blog - take you 30 seconds with google to sort it out and bish-bash-bosh, you can lambast away to your hearts content smile.gif

If you want to have a discussion, then by all means do it here.

cool.gif
Doug
tedstryk
There are really three facets to the manned vs. unmanned. The first is arguable - whether the science accomplished by robots can equal or best humans on the moon. The second and third are tied. If human settlement of space is our ultimate goal, and if there is something significant that warrants any costs to actually send humans - and this is a subjective question - then it might be easier to come up with 100 billion for a manned program than 5 billion for an unmanned one. The third is where the general public stands, which will determine political will.

It is worth remembering that many of the hardline Apollo opponents were the old-guard sky-scientists (I say that because many working in particle and fields today are much more understanding when it comes to the value of remote sensing) who also opposed cameras on robotic missions - see the Venus thread. And although scientists bemoaned the lack of emphasis on science in Apollo - it did indeed ride beack seet to just getting there and propaganda - I think we also have to be aware that without the race to put a man on the moon, there would have been no Ranger, Surveyor, Lunar Orbiter - or Zond, Luna, and Lunokhod. If you look at the science done by Apollo, it was far above the robotic technology of the day. I still see having a human present as being an advantage, although technology has improved the prospects for robitic missions. I also think that the fact that Harrison Schmidt being the only trained geologist-astronaut to fly is a factor - had more field geologists been sent, I think the scientific return would be improved.
dvandorn
I dunno about the lack of sending professional geologists to the Moon (with the exception of Schmitt) really hurting the science return, since the J mission crews were well trained in geology. VERY well trained. In essence, we sent six professionally trained geologists to the Moon -- only one of them had a degree in the field, but all of them could well have claimed such a degree.

-the other Doug
Richard Trigaux
QUOTE (djellison @ Feb 14 2006, 03:34 PM) *
If you want a ranting place ( and you've done plenty of it here, and formerly elsewhere ) then get a blog - take you 30 seconds with google to sort it out and bish-bash-bosh, you can lambast away to your hearts content smile.gif

If you want to have a discussion, then by all means do it here.

cool.gif
Doug


I agree. For once that I launch a thread, I would have prefered to have replies on the topic itself (manned missions serviced Moon rover) rather than a manned/unmanned debate, even if the later was interesting too.
AlexBlackwell
QUOTE (Richard Trigaux @ Feb 14 2006, 06:24 PM) *
I agree. For once that I launch a thread, I would have prefered to have replies on the topic itself (manned missions serviced Moon rover) rather than a manned/unmanned debate, even if the later was interesting too.

In that case, I apologize in advance for mentioning this. However, Springer Link is offering free online access to the recently published June 2004 issue of Earth, Moon, and Planets, which is a special issue regarding the scientific case for human space exploration.
Richard Trigaux
There was tremendous progress recently in the domain of autonomous drive, see Opportunity and Spirit, which are able of a safe obstacle-pits avoidance, and of some efficiency about circunventing obstacles. So a rover on the Moon will be able to take profit of these developments.
On the other hand, a Moon rover can be easily remote-controlled with a video link.

But the Moon terrain is much more rugged that what we see on Meridiani and even at Gusev. There are large rocks (metre or more) and many craters with slopes as steep as 30°. Even a flat surface perspective could hide a small but dangerous pit.

The problem is still worse if we consider that this rover will have to make long drives, thousands of kilometres, in a reasonable delay. This requires that it can drive fast, say in the 30km/h domain or more.

And driving on a treacherous terrain at such a speed with a more than 2s delay would quickly end to send the rover in a small but deadly pit, that the controler would not see behind a small fold of terrain.

So a Moon rover would have to be much larger than the Mars caddies. It has to be large anyway, to be of some use: carry a complete analysis lab, and eventually piggy-back an habitation module or LEM-like crew return module.

So it would need some features:
-large wheels
-long suspention arms
-active suspention able to absorb large shocks.
-forward looking cameras mounted high on top of "antennas".

Eventually an autonomous drive capability would allow to react in time to an unseen hazard even in a remote controled drive session.
BruceMoomaw
QUOTE (Richard Trigaux @ Feb 14 2006, 06:24 PM) *
I agree. For once that I launch a thread, I would have prefered to have replies on the topic itself (manned missions serviced Moon rover) rather than a manned/unmanned debate, even if the later was interesting too.


The trouble is that, in this particular case, there's simply no way to avoid bringing up the issue -- at least in connection with lunar exploration. (The issues involved with manned deep-space exploration, as I tried to make clear, really are different in nature, thanks to the vastly greater difficulty in teleoperating robots on any world farther away than the Moon.)
djellison
QUOTE (BruceMoomaw @ Feb 15 2006, 05:12 AM) *
The trouble is that, in this particular case, there's simply no way to avoid bringing up the issue


It's really very easy Bruce, you just have to stop making the point. It's that easy. If you can't stop making the point, then I'll start stoping you doing it the hard way - I'd rather you did it the easy way by restraint.

Doug
BruceMoomaw
OK.

As for a fast-moving unmanned lunar rover (of any type), I presume the solution to the problem of dangerous obstacles is a scanning lidar to recognize dangerously tall rocks and dangerously steep slopes ahead -- that is, exactly the same sort of thing planned for the MSL lander. We are, after all, starting to develop similar laser systems for passenger cars on THIS world. (I doubt that a purely visual recognition system, like that on the MERs, would be adequate -- at least until we learn more about how our own eyes compute recognition of features, and even that might be an inferior system on a world without the long-distance atmospheric blurring that we rely on so much to judge relative distances on this planet.)
Richard Trigaux
QUOTE (BruceMoomaw @ Feb 15 2006, 09:50 AM) *
OK.

As for a fast-moving unmanned lunar rover (of any type), I presume the solution to the problem of dangerous obstacles is a scanning lidar to recognize dangerously tall rocks and dangerously steep slopes ahead -- that is, exactly the same sort of thing planned for the MSL lander. We are, after all, starting to develop similar laser systems for passenger cars on THIS world. (I doubt that a purely visual recognition system, like that on the MERs, would be adequate -- at least until we learn more about how our own eyes compute recognition of features, and even that might be an inferior system on a world without the long-distance atmospheric blurring that we rely on so much to judge relative distances on this planet.)


Yes, a laser-sensing or lidar would be a good idea.

The MERs on Mars work the same than our eyes: they create a 3D map from two slightly different perspective views. This process has fundamental limits. For instance a slight hill on a flat terrain is often unseen, and it can hide a pit. Other illusions are possible, and to drive fast our cars on the road we need roads specially marked with colors, bands, etc. which allow our eyes to have a simple perspective view, univocal, or at least to detect the tricks (in the case of a slight hill, the side band appears sheared). Driving on the Moon at high speed would rather be like driving fast a tank on a virgin and hostile terrain. Tank drivers could testify about this...

A lidar (or rather a laser telemetre) scanning the front view would allow to directly make a 3D map. And an univocal map, without the above vision tricks. Even in the case the scan comes on the top of the slight hill, it detects an abrupt change in the distance, hinting for an unseen zone which can be treated as a hazardous zone.

The next step could be presenting the scene to an human driver. For this a color could appear on a synthetized view (or over a natural greyscale view) to indicate the distance. (Black could be very close, after brown, red, yellow, blue, white for the farthest). In such a view, the slight hill could appear like a color transition where the greyscale image appears of an uniform grey. So even a human driver could infer the presence of an unseen zone (the top of the slight hill could even appear highlighted) but robots would perform better, and in this case even an astronaut would prefer to rely on the robot, just monitoring it.
djellison
You see Bruce - not that hard. Here, have a cookie smile.gif


Seriously - the manned v unmanned stuff is old, repetative and boring -but if you want to thrash it out, do it in its own thread.

Doug
Bob Shaw
QUOTE (BruceMoomaw @ Feb 15 2006, 08:50 AM) *
OK.

As for a fast-moving unmanned lunar rover (of any type), I presume the solution to the problem of dangerous obstacles is a scanning lidar to recognize dangerously tall rocks and dangerously steep slopes ahead -- that is, exactly the same sort of thing planned for the MSL lander. We are, after all, starting to develop similar laser systems for passenger cars on THIS world. (I doubt that a purely visual recognition system, like that on the MERs, would be adequate -- at least until we learn more about how our own eyes compute recognition of features, and even that might be an inferior system on a world without the long-distance atmospheric blurring that we rely on so much to judge relative distances on this planet.)



Bruce:

There's also the raft of technologies demonstrated, by among others, Carnegie Mellon University in the DARPA unmanned desert race contest:

http://www.cmu.edu/cmnews/extra/050927_redteam.html

Bob Shaw
BruceMoomaw
The stereo visual feature-recognition system seems to work very well for the MERs; my main question is how well it would work on a much faster-moving vehicle of the sort we're talking about. A lidar system capable of automatically detecting dangerous obstacles or slopes ahead and slamming on the brakes would seem to be a useful addition to a manned teleoperator for a lunar vehicle.
Richard Trigaux
QUOTE (BruceMoomaw @ Feb 15 2006, 02:58 PM) *
The stereo visual feature-recognition system seems to work very well for the MERs; my main question is how well it would work on a much faster-moving vehicle of the sort we're talking about. A lidar system capable of automatically detecting dangerous obstacles or slopes ahead and slamming on the brakes would seem to be a useful addition to a manned teleoperator for a lunar vehicle.


As I said there are fundamental illusions that a stereo-vision system cannot dissipate. With the MERs it worked, because the rover looks, create a map, and advance of some tens of centimetres maximum, then stops and redo again. If an illusion is not eliminated at a given turn, it will necessarily be at one of the following. On a fast moving rover this will not be possible, as the braking distance can be greater than the safe vision distance. It is why your idea of a laser telemetre is interesting. It would not only be an emergency monitoring, but a telemetry laser mapping the soil in 3D provides a much safer map than just stereo vision, where hidden hollows are clearly visible and not confused with flat or uniform surfaces. So the 3D map would be interesting even for human operators, in remote control or even in the rover itself.
dvandorn
The biggest pitfall for an automated fast-speed (30-kph-plus) lunar rover is... pitfalls.

Even on the flattest lunar terrains, crater saturation means that there are literally thousands of craters of all sizes along any given straight-line path of even a few thousand meters in length. Lidar could "see" upcoming craters, sure -- as long as the near rim isn't higher than the far rim.

Problem is, there are a *lot* of lunar craters of rover-eating size that have uneven rims. They tend to be completely invisible to *any* line-of-sight system until it's too late to brake to avoid driving straight into them.

The LRVs had a maximum level-ground speed of about 15 kph, and the Apollo experience was that this was about the fastest safe speed to travel, to allow for braking or violent steering when such a hidden crater popped up right in your path. The only time the LRV drivers exceeded that speed was going down hills, where the terrain was spread out in front of them and therefore displayed its pitfalls to easy view.

And that was with human drivers, who were able to react with human reflexes. Robots are still incapable of reacting to driving conditions with anything approaching human reflex speeds. I doubt that's going to change any time in the near future.

Miss just *one* blocky-floored 5- to 10-meter crater and sail right over its rim, and you've just wiped out your billion-dollar robotic explorer.

I think robotic lunar explorers are going to be limited to at most a 10-kph pace for a while, yet...

-the other Doug
Richard Trigaux
QUOTE (dvandorn @ Feb 16 2006, 05:06 AM) *
The biggest pitfall for an automated fast-speed (30-kph-plus) lunar rover is... pitfalls.

Even on the flattest lunar terrains, crater saturation means that there are literally thousands of craters of all sizes along any given straight-line path of even a few thousand meters in length. Lidar could "see" upcoming craters, sure -- as long as the near rim isn't higher than the far rim.

Problem is, there are a *lot* of lunar craters of rover-eating size that have uneven rims. They tend to be completely invisible to *any* line-of-sight system until it's too late to brake to avoid driving straight into them.

The LRVs had a maximum level-ground speed of about 15 kph, and the Apollo experience was that this was about the fastest safe speed to travel, to allow for braking or violent steering when such a hidden crater popped up right in your path. The only time the LRV drivers exceeded that speed was going down hills, where the terrain was spread out in front of them and therefore displayed its pitfalls to easy view.

And that was with human drivers, who were able to react with human reflexes. Robots are still incapable of reacting to driving conditions with anything approaching human reflex speeds. I doubt that's going to change any time in the near future.

Miss just *one* blocky-floored 5- to 10-meter crater and sail right over its rim, and you've just wiped out your billion-dollar robotic explorer.

I think robotic lunar explorers are going to be limited to at most a 10-kph pace for a while, yet...

-the other Doug


Yes, this is a real problem. And a large lunar rover must be fast, otherwise it remains confined in one place. By the way, a rover at 15km/h needs one month to circle the Moon equator, (and at this speed it follows the Sun so that it always get energy). So after all there is no need to be much faster.

But even at 15km/h the problems are huge, and as it, no robot can do it, and no remote controling human operator either, with the 2s delay. Only a manned vehicule can drive in these conditions, and even at its own risks.

Then Bruce's idea of using a LIDAR is interesting. Such lidar beam could scan the landscape and do of it directly a 3D map, without the ambiguities of a stereo algorithm. For instance, in the (very common) case where there is an invisible pit (near rim higher than the far rim) a stereo vision can see only an uniform grey span, and not the pit, until it is too late. But a lidar scanning this place, say from bottom to top, detects an instant increase in distance when the beam leaves the near rim and reaches the far rim. From this it can infer the presence of an unseen area, potentially a pit. And this unseen area could be displayed on a screen as a black span: the operator just has to avoid it. This is why the lidar scan is infinitely superior to the stereo algorithm and even to human vision.


In the long run, a fast rover on the Moon is ubiquitous. Just chinese taikonauts land by surprise? The rover can be here and wave a free Tibet flag... err provide its science analysis facilities.


Note that if the sciences instruments are in racks, and the racks opening to the top, we can conceive an automated lander with big legs, the rover sneaks under, and the lander can automatically change an instrument. Difficult, but not absurd: the task can be resumed to grasping a knob, pull it, and plug another instrument. Basic topic of robotic studies.
BruceMoomaw
Look. Even on Earth, recreational 4WD operators are consistently told NOT to drive fast on rugged terrain, but to "crawl" over obstacles instead, at no more than 10-20 km/hour. Given the radio time lag on a teleoperated rover, cutting the speed to only a few km/hour seems entirely logical. Nor, given the geological-survey purpose of such a vehicle, is there any scientific benefit in driving faster -- you'll just miss interesting sampling sites, which is after all your purpose rather than trying to set a speed record.
djellison
QUOTE (Richard Trigaux @ Feb 16 2006, 07:08 AM) *
But even at 15km/h the problems are huge, and as it, no robot can do it,


http://www.darpa.mil/grandchallenge/
131 miles in 6hrs 53 mins

Call it 18mph, or 28kph.

Yes - I know - not entirely applicable to lunar exploration - but it's untrue to say 'no robot can do it'.

The technology is beginning to be available whereby it's entirely plausable that a rover could operate on the moon at a pace similar to that of the LRV of the Apollo era, unmanned, without totally 'remote' control.

Doug
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