Subject: Space-tech Digest #133 Contents: Near-term space priorities (7 msgs) Water launch / Bob Truax (1 msg) Telerobotics (3 msgs) Near earth mining / deflecting asteroids (3 msgs) ------------------------------------------------------------ Date: Wed, 11 Nov 92 08:34:47 PST From: can2can@ziggys.cts.com (Tim Edwards) To: space-tech@cs.cmu.edu Subject: Priority pt2 To expound: What type of tech stuff are we discussing? What needs work? My _personal_ priority is the Earth-crossing asteroids/comets which provide both a resource and a potential hreat. My preference for handling the matter is a set/fleet of ships, one to be a piloted ship with telerobotic operators. The rest to be big mining robots and small repair/maintenance 'bots. There is no need for AI to do predictive control, because the controler will be near enough for real-time link. There is no need for perfection, the repair bots go out to fix the miners and come in to get themselves fixed by people. Supporting infrastructure includes a mine/launcher on Luna, and deep-probing radars at the trojan points. Downlink to surface is not needed, the operators can message the asteroid strip-mine group dirrect. Did I seem to be bashing the techs at NASA? sorry, I know that not all the techs left, but most followed the tech jobs, and NASA is mostly engaged in making excuses these days. I do not recomend 'nuking' NASA, just that we should be concerned with how to get off planet, not the political support of NASA. BTW, I am not averse to mining the 'beyond Mars' asteroids, I just think we need to start closer. I did one thing with my post, the traffic is _way_ up. can2can@ziggys.cts.com - BBS (619)262-6384 Ziggy's Den Of Iniquity ------------------------------ From: ssi!lfa@uunet.UU.NET (Louis F. Adornato) Subject: Re: Priority pt2 To: uunet!cs.cmu.edu!space-tech@uunet.UU.NET Date: Wed, 11 Nov 92 15:45:29 CST > > To expound: What type of tech stuff are we discussing? What needs > work? My _personal_ priority is the Earth-crossing asteroids/comets > which provide both a resource and a potential hreat. My preference > for handling the matter is a set/fleet of ships, one to be a piloted > ship with telerobotic operators. The rest to be big mining robots and > small repair/maintenance 'bots. There is no need for AI to do predictive > control, because the controler will be near enough for real-time link. Much better. I assume that you want all of this started next week, without any intermediate steps. The parts of this plan that aren't impossible are well beyond the scope of existing technology. Ironically, a lot of the intermediate steps are already being worked on by (of all people...) NASA. First, there's the question of having a permanent human presence onorbit. The "mother ship" here sounds like it'll have to do everything that SSF _wants_ to do, and then a darn sight more. I think this scheme seriously underestimates the distances and velocities involved with earth crossings. As for distance, I don't have the numbers at hand, but I don't think that there are many approaches per year that come within .5 light second (93e3 miles) of the L5/L6 points. Anything further out is going to need either predictive control or a local operator. Then there's the problem of matching the orbits of the mining robots to the asteroids/comets. This is a much more difficult operation than a cometary flyby; the mining robots will have to "softland" on the bodies (whereas the Halies probes merely got into the same neighborhood and took pictures for a few hours at most). Once the robot has grapled the target, unless there's some way of imparting a _large_ delta v to the target, both of them will soon be far enough out that the transport lag will make teleoperation impossible. Lacking that, the robot will be able to mine only until it's reached it's maximum operating distance, and then will have to match orbits with the Earth once more, this time carrying whatever materials it's mined from the target. This all represents a _lot_ of delta v. On the other hand, I'd _love_ to be the one who gets to do the navigation software. It should also be pointed out that the state of the art in microgravity grappling isn't terribly reliable. As evidence, look at the troubles that Thuot had with the InTelSat rescue, and that was under much more controlled conditions (and with humans present) than anything that will be found with a natural body. > There is no need for perfection, the repair bots go out to fix the miners > and come in to get themselves fixed by people. Again, look at the InTelSat rescue. Granted, that _particular_ problem won't come up again (the latch pressure on the grappling bar was set about 5 lbs too high), and the mining robots would presumably be designed for capture/IFM, but a lot more experience in microgravity work is going to be needed before a system such as this will be feasable. NASA's already working on this. > Supporting infrastructure > includes a mine/launcher on Luna, and deep-probing radars at the trojan > points. Downlink to surface is not needed, the operators can message > the asteroid strip-mine group dirrect. Downlink to _which_ surface from _where_? If you're talking about operating the mine/launcher from an L point, rerun your numbers; that's well outside the maximum transport lag distance. > Did I seem to be bashing the techs at NASA? sorry, I know that not all > the techs left, but most followed the tech jobs, and NASA is mostly > engaged in making excuses these days. Geez, I TRIED to rise above flaming but he just won't let me... OK loudmouth, just what exactly do you base this on? I know some pretty capable people in NASA who really bust hump on each and every mission. And they're doing it with outdated equipment under a system that We The People allowed our elected representatives to saddle them with. Can you come up with a method of (f'rinstance) making a fuel line sensor that can be repreatedly exposed to liquid hydrogen over a ten year period and not become brittle, meets current space rated reliability and safety requirements, can be retrofitted into the existing fleet, can be explained to level II management, and can be purchased through a minority vendor? As soon as you can handle this _and_ a few thousand other problems of similar nature, you've earned a right to make with the accusations. Until then, you're nothing more than a waste of bandwidth. I can understand it when I hear this attitude from the general public; they see Luke Skywalker jump into his spaceship and head off to Aldeberan without so much as a preflight and they can't understand why NASA doesn't operate that way. They have no idea that engineering is a slow, careful, and sometimes excruciatingly boring process. Since you seem to be in this category, I have a news flash: space exploration is difficult, complex, and dangerous. > I do not recomend 'nuking' NASA, > just that we should be concerned with how to get off planet, not the > political support of NASA. Beleive it or not (and you won't) that's what most of the people in NASA are interested in. BTW, I know _managers_ at NASA who've been putting people in space since I was still wetting diapers. One in particular helped develop the concept of software source code control back when my biggest worry was who to take to the sock hop. I learned more from him in a year than I did in a decade in the private sector. I doubt you'd be qualified to sharpen his pencils. And he's spent his entire career making significantly less than he would with one of the contractors, because he beleives in what he's doing. What have _you_ contributed to the Cause besides hot air? > I did one thing with my post, the traffic is _way_ up. Congratulations; you're like the grain of sand at the center of a pearl (i.e., a major irritant). I will admit this; your not-so-original idea about recovering the Saturn V capability has always appealed to me, and I'm glad to see it resurface from time to time. Lou Adornato | The secretary (and the rest of the company) Supercomputer Systems, Inc | have disavowed any knowledge of my actions. Eau Claire, WI | "In God we trust - everyone else, show your data" uunet!ssi!lfa/lfa@ssi.com | - Mission Evaluation Room, JSC, Houston, TX ------------------------------ Date: Thu, 12 Nov 1992 12:37 EST From: RNBJ@VAX5.CIT.CORNELL.EDU Subject: What is being done? I see many excellent-sounding proposals (I am not an engineer, but a lowly physiologist) and I wonder how much progress is being made on them in practice. Also, I am constantly being abused by friends who say that space station Freedom is a useful piece of hardware, when according to everything i have read it is an expensive orbiting chunk of Congressional pork. Incidentally, I remember something like 20 shuttle flights will be required to get it up there while the Russians have offered the Energia which can do it in one or two. Is this true, and if so, why are we not doing it when a shuttle launch is 35 million, while the Russians would probably do it for $1.50 and tenure (which sucks, as they have a better space program than we do and deserve better, but that is politics). Also, hasn't Mir already done th elow-grav bio experiments that Freedom is supposed to do? This may seem ignorant to all of you discussiong new fleets to build, but if anyone gets a chance, could they reply? Thanks. -Arcimontanvs rnbj@vax5.cit.cornell.edu ------------------------------ From: henry@zoo.toronto.edu Date: Thu, 12 Nov 92 13:53:55 EST Subject: Re: What is being done? To: space-tech@cs.cmu.edu >... I am constantly being abused by friends who say that space station >Freedom is a useful piece of hardware, when according to everything i have >read it is an expensive orbiting chunk of Congressional pork... It would be better to post queries like this to the sci.space newsgroup. This mailing list was originally intended for *technical* discussion. (I'd suggest that if it doesn't have numbers in it, it doesn't belong here.) A short answer: you and your friends are both right. Freedom will be useful, even though it could be done much more quickly and cheaply without the pork-barrel aspects. >...something like 20 shuttle flights will be required to get it up there >while the Russians have offered the Energia which can do it in one or two. Is >this true, and if so, why are we not doing it... There are a number of problems. You'd probably need at least a partial redesign to use Energia, and there is great resistance to that because the station has already been redesigned too many times. Energia's reliability is uncertain (it has only flown twice); this matters because there is no backup hardware being built for the station. Russia's political stability is open to question. Energia cannot launch into the station's preferred orbit, because the Energia pads are at too high a latitude. None of these things is utterly prohibitive, but the combination isn't favorable. >... Also, hasn't Mir already done th elow-grav bio experiments >that Freedom is supposed to do? ... No, if only because Western access to Mir has been very limited. Henry Spencer at U of Toronto Zoology henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: Thu, 12 Nov 92 14:48:36 -0600 From: ewright@bach.convex.com (Edward V. Wright) To: henry@zoo.toronto.edu, space-tech@cs.cmu.edu Subject: Re: What is being done? The Shuttle's reliability is also uncertain. The chances of an accident on any given flight are probably less for the Shuttle than for Energia, but the downside is much greater. One more Challenger-type accident and the Shuttle could be grounded permanently. In the best case, there would be another 2.5-year delay. Another problem is that the Energia production lines have been shut down. If production isn't restarted soon, I expect they'll be converted to some other use. ------------------------------ From: henry@zoo.toronto.edu Date: Thu, 12 Nov 92 16:35:36 EST To: "Edward V. Wright" Cc: space-tech@cs.cmu.edu Subject: Re: What is being done? >The Shuttle's reliability is also uncertain... However, we're beginning to have some idea about shuttle reliability -- a failure rate of maybe 1-2%. Energia's failure rate is almost totally unknown at this time. >Another problem is that the Energia production lines have been >shut down. If production isn't restarted soon... Given a prompt decision, this is a non-problem; a $xxxM order backed by hard cash goes a very long way in the ex-USSR. It does set somewhat of a time limit, though. Henry Spencer at U of Toronto Zoology henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: Thu, 12 Nov 92 21:35:56 EST From: John Roberts Disclaimer: Opinions expressed are those of the sender and do not reflect NIST policy or agreement. To: space-tech@cs.cmu.edu Subject: Re: What is being done? >One more >Challenger-type accident and the Shuttle could be grounded permanently. >In the best case, there would be another 2.5-year delay. The minimum interval would be the length of time to find the cause of the accident. If the decision is made to make hardware changes to fix the cause (not guaranteed - for some predicted failure modes, the most sensible approach is to carry on as usual), and if the hardware changes take a long time, then the total delay could be as long as you describe. The interval after Challenger was an opportunity to fix *many* problems that had become apparent over the previous few years, and others that were turned up during the investigation. (In fact, a redesign of the SRB joints had already been scheduled - it didn't come along in time to save Challenger.) John Roberts roberts@cmr.ncsl.nist.gov ------------------------------ To: space-tech@cs.cmu.edu Subject: Water launch From: can2can@ziggys.cts.com (Tim Edwards) Date: Thu, 12 Nov 92 09:12:49 PST Bob Truax is a local (California) man, that I have heard talk on his problems geting past government monopoly/NIH attitudes. His proposal is for a water-launch, pressurised tank booster called the Sea-Dragon. I belive it has been refered to recently in terms of 'Cortex-dump'... name not found. I finaly got the content addressable link... can2can@ziggys.cts.com - BBS (619)262-6384 Ziggy's Den Of Iniquity ------------------------------ To: space-tech@cs.cmu.edu Subject: Telerobotics From: can2can@ziggys.cts.com (Tim Edwards) Date: Thu, 12 Nov 92 09:16:52 PST The short term answer to the problems of life support, breath-down times and a lot of other 'how do we survive working in space?' type questions is telerobotics. We send an operator that stays inside the can, while doing any required work outside with a telerobot. The operator needs to be quite close to the operation, so building SSF would involve a resident 'assembler' bot, with controls commuting with the parts delivery crew. The attempt to build AI is way behind schedule, we can't wait for the researchers to build a robot to send _instead_ of a person, we need to send people with waldos. can2can@ziggys.cts.com - BBS (619)262-6384 Ziggy's Den Of Iniquity ------------------------------ To: Tim Edwards Cc: space-tech@cs.cmu.edu, gwh@lurnix.COM Subject: Re: Telerobotics Date: Thu, 12 Nov 92 15:38:37 -0800 From: gwh@lurnix.COM I think that we went through this loop once on sci.space before... 8-) Summary: Teleoperated waldos have a lot of the disadvantages that robotics in general do: poor nonvisual feedback, it's hard to build them with as many degrees of freedom (and freedom of motion in each degree) as people tend to have, it's hard to build vaccum and zero-g rated _anything_ that moves, nonetheless in that many degrees of freedom. That having been said, locally controlled robotics do have a place in orbital operations. Just as ground-control and men-in-spacesuits have their places. There are some things you can't do with some of the above solutions; there are some things that you can't do without two or three of those solutions together. Saying that waldos or better spacesuits or whatever is a fixall for eva ops misses the inherent difficulties in any zero G vaccum work; you often need both a man there in a suit and a robot or two to help him along. Or visa versa. -george william herbert gwh@lurnix.com ------------------------------ To: space-tech@cs.cmu.edu Subject: Telerobotics From: can2can@ziggys.cts.com (Tim Edwards) Date: Fri, 13 Nov 92 07:49:22 PST >Much better. I assume that you want all of this started next week, >without any intermediate steps. The parts of this plan that aren't >impossible are well beyond the scope of existing technology. Telerobotic operators are beyond existing technology? Tell that to the people that publish progress reports in 'NASA Tech Briefs'. Progress continues in close-link virtual presence control of waldos. Moreover, the controler/VR part of this is something that _we_ can actively engage in without a federal grant. >Then there's the problem of matching the orbits of the mining robots to >the asteroids/comets. This is a much more difficult operation than a >cometary flyby; the mining robots will have to "softland" on the bodies... Sounds like we need a docked configuration, long flight time out to the ore body, then a mining/refining process that throws off high velocity waste material. By the time the ore is refined, it is parked. The mother will probably need to soft land on the rock as soon as it is spun-down, so that it does not have to expend separate reaction mass >Again, look at the InTelSat rescue. Granted, that _particular_ problem >won't come up again... we design the repair 'bots to grapple targets on the miners or the mother. If a repair 'bot 'dies', another will tow it to the mother for in-air repair. >> Downlink to surface is not needed, the operators can message >> the asteroid strip-mine group dirrect. >Downlink to _which_ surface from _where_? If you're talking about operating >the mine/launcher from an L point, rerun your numbers; that's well outside >the maximum transport lag distance. Downlink to any surface. The sixties had chirp-radar, the seventies added the phased array antenna. We use a pyroceramic core with metal waveguide, then glass over the metal. We also provide resident teleoperators for the antenna maintenence 'bots. When a potential ore body is detected, it is plotted at the detecting radar, then the appropriate mother ship (start with one, but the time to station and time on station will probably dictate more than one set) is notified of the desired orbit match. The mine and launcher will again be operated by teleoperators, these will be on the Lunar surface. --- tear here --- >> Did I seem to be bashing the techs at NASA? sorry, I know that not all >> the techs left, but most followed the tech jobs, and NASA is mostly >> engaged in making excuses these days. > >OK loudmouth, just what exactly do you base this on? I know some >pretty capable people in NASA who really bust hump on each and every >mission....Can you come up with a method of (f'rinstance) making a fuel >line sensor that can be repreatedly exposed to liquid hydrogen over a >ten year period and not become brittle... The political/bureocratic stuff is not part of the engineering. Sending someone through a deficient education, then lowering your standards to accomodate is not good engineering. Why do you want to expose a fuel flow sensor to the fuel? If you have a thermal insulator at two points in the fuel line, then the thermal load of the isolated section is a function of the mass flow through it, if any. A platinum temperature sensor, a resistive heater, and an 8051 to run the job. Contact Omega for a quote. >I can understand it when I hear this attitude from the general public; >they see Luke Skywalker jump into his spaceship and head off to >Aldeberan without so much as a preflight and they can't understand why >NASA doesn't operate that way. They have no idea that engineering is a >slow, careful, and sometimes excruciatingly boring process. You do it right, then you check it, then you get someone else to check it, then you prototype, debug, recheck, then you _ship it_. I know. When do we see the shipment of six shuttle loads per year? >Since you seem to be in this category, I have a news flash: space >exploration is difficult, complex, and dangerous. I have a news flash, not exploring space will be fatal. More people died putting a bridge over San Francisco Bay than we have lost in space-craft. The priorities need reseting to acceptable risk, the way they are for parachute riggers 'you rigged it, you get to jump with this one'. can2can@ziggys.cts.com - BBS (619)262-6384 Ziggy's Den Of Iniquity ------------------------------ Date: 12 Nov 1992 10:54 -0400 (EDT) From: BEAUFAIT%CEBAFVAX.BITNET@BITNET.CC.CMU.EDU Subject: near earth minning To: space-tech@cs.cmu.edu why not herd your asteroids with a hi energy laser. You dont have to match orbi ts or get extreamly close (more than a few miles.) Boil off material in the oppo sit direction of which way you want the asteroid to move. Yes this is very energ y entensive but you dont throw away alot af reaction mass on unessissry delta/v changes of your minning ship and since no romote manipulation long loop time rem ote aiming and fireing sounds fessble. ------------------------------ Date: 12 Nov 1992 13:41:09 -0500 (EST) From: "GORDON D. PUSCH" Subject: Re: near earth minning Lasers are *appallingly* inefficient. Tether a ring-shaped solar-sail to the asteroid instead, and just focus sunlight on it (either _Analog_ or _Asimov's_ ran a fiction piece on this as the cover-story a few months ago, can't remeber which; Kelly Freas did the painting...) Gordon D. Pusch ------------------------------ Date: 13 Nov 1992 13:01 -0400 (EDT) From: BEAUFAIT%CEBAFVAX.BITNET@BITNET.CC.CMU.EDU Subject: Re: near earth minning To: space-tech@cs.cmu.edu For efficiancy of lasers we are contemplating a free electron laser... With solar sails you still have to dock attach and deploy - a much mor difficult proccess. *boy i hate this editor* ------------------------------ End of Space-tech Digest #133 *******************