Projects - projects we can do now to get to Mars

RobertDyck · 2003-04-23 12:17:47

This list will discuss projects we can undertake to get us to Mars. The focus is not another analogue, but real flight hardware, enabling technologies, and developing ground equipment to develop flight hardware. The suggestions for a greenhouse do touch on another analogue, but the greenhouse discussed here will use an inflated enclosure with airlock, hardware light enough to be realistically transported to Mars, and a mineralistically accurate soil simulant. Analogue spacesuits have been done, so let's avoid those. Any suit discussed here should be safe to wear in space, not based on a garbage pail. We can discuss business plans for these projects to build to a real manned mission to Mars.

RobertDyck · 2003-04-23 12:18:25

I made a few suggestions to the Mars Society Technology Roadmap team on September 22, and September 28, 2002. These suggestions were intended to be things that the Mars Society or its chapters could work on now. I included a couple projects that chapters have already started. Carol Stoker intended to compile a list that chapters could pick from to pursue projects. Could we get some of these started? Which projects would people be interested in working on?

- spacesuit: we need a suit that is light-weight enough to permit operations in Mars gravity, and dexterous enough to permit climbing rough terrain, and safe enough to ride a unpressurized rover (similar to an ATV). The Australian chapter is proceeding with MarsSkin to develop a mechanical counter pressure suit to accomplish that.

- PLSS: we need a spacesuit life support system that permits frequent EVA's on Mars, can be field serviced while outside on Mars, minimizes consumables brought from Earth, and is light-weight. I suggest a regenerable carbon dioxide sorbent, and lithium-ion batteries.

- PLSS details: I would like to add the suggestion of a composite oxygen tank. I collected a couple relevant papers from AIAA regarding composite pressurant tanks. I also have details regarding lithium-ion batteries of the appropriate size for a spacesuit that can withstand 1,500 charge/discharge cycles before capacity is reduced to 80% of new. On the Spacesuit-Mars group I suggested a closed-loop backup system using lithium hydroxide sorbent, a backup oxygen tank, and oxygen feed by a pressure regulator. The backup operates with no electricity, so it works even if the battery freezes. I also suggested a microcontroller to control the system, and a simple serial cable to the user interface. That permits other groups to work on user interfaces separately; suggestions include a palm-top computer attached to the spacesuit forearm, or a wearable computer with eyeglass mounted heads-up-display.

- spacesuit computer: The Canadian chapter is working on a data logger. That is a wearable computer intended for use in a spacesuit. Their focus is on automation of geology field notes.

- spacesuit thermal and outer protection layers: The current EMS uses layers of aluminized Mylar to provide thermal protection. That works fine in a vacuum, but will not work in the atmosphere of Mars. Aspen Aerogels is now producing drapeable aerogel, which is used in an Antarctic exploration jacket as well as commercially available winter outerwear. Its durability should be studied, and compared with Thinsulate. The EMS uses Kevlar for the micrometeoroid layer; very strong and relatively light-weight, but quite stiff. Alpine mountain climbing jackets use Goretex as the outer protective layer; perhaps that would be appropriate on Mars. I suggest a spacesuit with a replaceable outer layer: aluminized Mylar thermal protection and Kevlar micrometeoroid layer for space, and Thinsulate or aerogel thermal protection and Goretex scuff/dust layer for Mars.

- launch vehicles: catalogue launch vehicles available, their cost to develop or restore infrastructure, and cost per launch.

- hab life support system: existing technology favours a water electrolysis similar to the Russian system currently operating on ISS to generate oxygen. Exactly what is required to add a sabatier reactor? What is the state of water recycling that NASA developed as part of their Advanced Life Support System project? Can we put these together to recycle oxygen with over 95% efficiency? What is the mass and power requirements for such a system?

- microwave regeneration of carbon dioxide sorbents: A paper was written regarding microwave regeneration of silver oxide (Ag2O), but the paper does not cover solid amines. Would solid amines be lower mass than silver oxide? Are solid amines compatible with microwave regeneration? Microwave regeneration is more power efficient than electro-resistive heating elements. Can we do a literature search to document what has been done?

- aerocapture: this technology has been developed by the aerospace industry, but is not yet considered a mature technology. One of our members (Jason Hoogland) is completing his Ph.D. in Aerospace Engineering specializing in heat shields and aeroshells. NASA is willing to fund research into aerocapture and has a current open research solicitation: NRA-02-OSS-01-ISPT2, IN-SPACE PROPULSION TECHNOLOGIES - CYCLE 2. We HAVE to get these guys together.

- MarsGravity: The TransLive project is proceeding under the name MarsGravity; what can I say? Go Team!

- greenhouse envelope material: an inflatable greenhouse has been proposed for Mars, as well as a garage tent for the rover. What material can withstand the Mars environment? Although detailed mineralogical characterization of Mars regolith is yet to be completed, a rough guide is available from Sojourner data, and the super-oxides described to explain Viking data. Mars Odyssey has given us a good estimate of surface radiation. One material suggested is Tefzel film, but the question of UV stabilization has been raised. Teflon FEP has half the tensile strength of Tefzel, but is more stable; would Teflon FEP do?

- greenhouse design: structure and temperature control

- soil simulant: It would be very advantageous to have a soil simulant that is mineralogically the same as Mars regolith. That requires an accurate knowledge of Mars regolith. I have talked to H. W?nke and T. Economou about results from Mars Pathfinder's APXS instrument, exchanged email with Hap McSween about CIPW analysis of the APXS data, and read papers by Phillip Christensen about TES data from MGS. The APXS data gives accurate elemental concentrations but not how they are organized into minerals. The results are so different from terrestrial minerals that a reliable description of Mars minerals remains elusive. Perhaps Mars Odyssey's THEMIS instrument will help. NASA has a simulant, JPL-MARS-1, which does have the right color, texture, and particle size, but its elemental make-up is quite different than Mars regolith. Once an accurate description of Mars regolith is available, we should develop a new simulant by blending terrestrial minerals and exposing them to UV in a Mars Jar to produce the super-oxides.

- auto-navigation software: this may be a larger project, but the Mars Society has many talented computer programmers and the requirements are just time and a personal computer. Autonav software would start with astronomical image recognition. This would take an image from a CCD digital camera and recognise stars, planets, and key asteroids. The position of planets and asteroids relative to known stars would be used to triangulate the spacecraft's current position. That position data would be matched to the projected flight path, and course adjustments calculated. Once delta-V is calculated, that can be translated into thruster firing duration, throttle setting, and timing. A computer simulation could input different spacecraft mass and thruster configuration. Machine readable star catalogues are available (I have a couple).

- benzene/oxygen rocket engine: Robert Zubrin's company Pioneer Astronautics has come up with a new process for In-Situ Propellant Production. The new MetaMars reactor takes methane and converts it into benzene and hydrogen. The hydrogen can be used to make more methane. Benzene has a higher carbon to hydrogen ratio, so more propellant is made with less hydrogen. The result is 1:45 mass ratio of hydrogen to benzene/oxygen propellant instead of 1:18 ratio of hydrogen to methane/oxygen. The next step is to find a rocket engine that uses benzene/oxygen and has at least as high a specific impulse as the engines available for methane/oxygen.

- benzene/oxygen fuelled rover engine: I had considered use of benzene to fuel the rover. There are currently 4 groups working on analogue rovers. We could set-up a group to design a light-weight engine that operates on benzene/oxygen. I know we have members who are automechanics. Pure benzene and air makes a poor fuel due to its high carbon content, but what about benzene/oxygen? The problem with benzene for analogue rovers is that in large quantities it is toxic.

- benzene storage: Storing benzene for rocket fuel is another issue. Pure benzene remains liquid to +80.1?C (+176.2?F), but it also freezes at +5.5?C (+41.9?F). Liquefying benzene could be an issue on Mars. The hot spot I have seen from MGS data was +24?C, but that is not the average daytime temperature on Mars. Mars Pathfinder recorded a high of -8?C in the day to a low of -77?C at night. What additives could reduce the freezing temperature to Mars temperatures? Could those additives be derived easily from hydrogen, carbon dioxide, water, oxygen, methane, and/or benzene? How would such additives affect rocket performance?

- Radiation hardening electronics: The MarsGravity group suggested a distributed electronics system that uses microcontrollers. That idea is good in principle, but can the microcontrollers survive conditions of space? Several commercial-off-the-shelf radiation hardened electronics are available. This includes '486 and Pentium based single board computers, memory chips and modules, MSI chips (data buffers, A/D and D/A converters), power MOSFETs, and individual '386DX chips; but no microcontrollers. Maxwell Technologies received an SBIR grant from NASA to develop a paint-on coating called RadCoat for commercial electronic boards to shield against radiation. Although NASA paid for development, they decided not to market it. Since this was paid for by NASA, can we get documentation on it directly from NASA?

RobertDyck · 2003-04-23 12:21:43

One slightly more ambitious project is to produce a real micromission spacecraft to send to Mars. This would demonstrate we can get something to Mars for real. I discussed a small balloon under the topic "Mars Society Initial Mars Mission"; details are there.

RobertDyck · 2003-04-23 12:36:03

One extremely ambitious project would be to bid for the Orbital Space Plane. The primary objective would be to produce a small and sustainable spacecraft. I suggested basing it on the X-38 but scaled down to 4 astronauts instead of 7. The HL-20 was designed for 10 astronauts, the modification to reduce it to 4 astronauts was simply to remove seats, no effort was made to reduce its size or mass. This means the HL-20 requires a Delta IV Large with its 3 core modules: launch price $170 million. A purpose built OSP for only 4 astronauts should fit on an Atlas V 401: launch price $77 million. Since the Soyuz FG (the latest launch vehicle for the 3-crew Soyuz-TM spacecraft) has a launch cost of $50 million, use of an EELV with only 1 core module would be cost competitive on a per astronaut basis with Russia's Soyuz.

One aerospace engineer I talked to suggested making the OSP a capsule rather than a lifting body. This would reduce mass further, and a steerable parafoil would permit controlled landing. The capsule could be designed to be reusable, although the heat shield would be an expendable ablative single unit. A single unit would make the heat shield more robust, and replacing it with a new one may be less expensive than servicing the current shuttle's tiles.

A lifting body OSP would use a reusable heat shield do to the more complex shape. A lifting body could permit dipping into the atmosphere for a manoeuvre to alter orbital inclination. This would make the OSP much more manoeuvrable. A capsule would be strictly up-and-down.

Could we undertake a serious engineering design for an OSP? Even if we don't land the contract, a serious design could coerce one of the major aerospace manufacturers to produce a small OSP to out compete us. An OSP that uses a single core module EELV booster would have an operational cost low enough to make it sustainable without draining all of NASA's funds.

Bill White · 2003-04-23 13:05:57

Robert, I have a bachelor's degree in American history and a law degree. I guess I can be the cheerleader.

Oh - I do sometimes have luck at getting people to work together - maybe that is worth something. . .

clark · 2003-04-23 13:58:28

I can play 'red team', but I for one would not feel confident in a spaceship, or a spacesuit, of my own design.

"what's wrong with a garbage pail space suit?"

Phobos · 2003-04-23 15:44:21

- spacesuit: we need a suit that is light-weight enough to permit operations in Mars gravity, and dexterous enough to permit climbing rough terrain, and safe enough to ride a unpressurized rover (similar to an ATV). The Australian chapter is proceeding with MarsSkin to develop a mechanical counter pressure suit to accomplish that.

I wish the MS would do a better job of publicising these types of things. I think the member roles might increase a bit if people saw that the MS wasn't just running the analogue stations. If the MS succeeded in contributing significantly to developing something like a very flexible, durable, and comfortable spacesuit that was used on an actual manned mission I think it would do wonders for bringing the MS out of the darkness. To be honest, spacesuit design is the most fascinating thing to me for some reason. I just can't envision living on Mars if I have to use huge, heavy, and bulky spacesuits like those the lunar astronauts wore.

soph · 2003-04-23 16:39:40

I believe the Soviet (now Russian) Space Agency had developed much more comfortable, flexible, and even customizable suits while Mir was aloft.

RobertDyck · 2003-04-24 02:47:52

The Australian project MarsSkin is working with Dr. Allen Hargens and Dr. Paul Webb on a mechanical counter pressure suit. Dr. Webb was the researcher who originally proposed it and worked on it for NASA in the late 1960s. Dr. Hargens has been working on it recently. Mechanical counter pressure is the generic term, it has been called a space activity suit, elastic leotard, skin suit, and in the book Red Mars was called a Walker.

I'm told the other spacesuit researchers at NASA scoff at the idea; their idea of a Mars suit is a hard suit: completely rigid with rotating wedges at the joints, or an accordion joint with metal rings. It would be a lot more convenient to have a tight spandex suit with a few gel pads. A cut in the suit would mean you get a bad bruise at that spot; the entire suit does not decompress. The cut can be repaired with a sewing kit. Light weight suits would take little storage room so several backup suits could be brought to Mars. Mars has fines so dust contamination is a given, spandex suits could be thrown in the washing machine. With 14 months on the surface and a small habitat, the crew members will spend much time outside. Wear over 14 months will be significant; an easily repairable suit is a must, especially one that can be repaired while wearing outside on the surface of Mars.

The issues regarding the mechanical counter pressure suit are keeping constant pressure on joints. Shoulders were found to not be a problem. The genitals were dealt with by a gel filled bag to distribute the pressure. Breathing was facilitated by an air bladder over the chest and upper abdomen. The helmet was connected via hose to the bladder and a hard exterior held the bladder to constant volume. I feel that shell could be replaced with a non-elastic fabric vest.

Mitch Clapp devised a glove to work with the existing EMU, the space shuttle suit. Its only problem was the join between pressurized EMU sleeve and the elastic glove. The pressure had a tendency to push the hand out of the sleeve; so an over glove without fingers was devised to hold the hand back. The wrist had a neoprene air dam cuff. Unfortunately funding was cancelled after the prototype was proven. An aerospace company took up the glove, but then a merger resulted in its cancellation again.

The Russian Sokol suit designed for launch and re-entry in a Soyuz is a lot lighter than the EMU or Russia's Orlan suit. Orlan was designed for EVA just like the EMU. The Sokol does not include a life support backpack; it relies on an umbilical from the spacecraft.

turbo · 2003-04-24 16:35:58

Hello Robert!
I too watched with interest the testing of the MarsSkin suits at MDRS this field season. As yet, there seems to be no contact between the Aussies and the spacesuitMars Group. With Crew 17's results of the "Agents" the dataloggers may have been overshadowed, but I think they should continue in development.

A composite pressure tank for a PLSS may be they way to go, but spun aluminum may have to do for awhile.

As for existing launch vehicles, does anybody have any idea what happened to the old Titan "citybuster" ICBM's? Those boosters may be the ticket for a small probe to Mars.

I would love to see another craft be built after Translife/MarsGravity and have a few ideas on where to get materials, I just don't know how to weld aluminum.

For starters, a small Chapter Project to replace "The Blob" at MDRS with an actual structure would be fabulous, and yes I've got some ideas there. Another project could look at replacing the radio repeater, and another to maybe buy/build some more devices like the Power Pod.

Be well All!
P

Bill White · 2003-04-25 10:07:43

Here is a project I have long fancied. . .

Take a refuse filled Progress from the ISS (scheduled for incineration in the atmosphere) and take a Soyuz ferry/taxi (scheduled for returning crew to Earth following normal ISS crew rotation) - - tether them together and spend 24 or 48 or 72 hours doing tethered flight manuevers before normal re-entry.

Tether induced artificial "gravity" is an area of technical expertise needed for "humans to Mars" unless we first build some really fast nuclear powered ships. Any short term mission, however, would need a method to offset the health risks of extended exposure to micro-gravity.

The Mars Society or a team of volunteers could solicit sponsors for the additional cost of this mission. The Discovery Channel comes to mind at once. Our team would contact potential sponsors and the appropriate Russian officials and seek to broker a deal under the aegis of the Mars Society.

Total costs should be minimal as the Progress and the Soyuz are already fully paid for and are already in orbit. Original programming from inside the capsule could generate the revenue needed to design and deploy the tether and pay for the minor additional ground support needed for such a mission.

Thoughts?

clark · 2003-04-25 10:13:01

Take a refuse filled Progress from the ISS (scheduled for incineration in the atmosphere) and take a Soyuz ferry/taxi (scheduled for returning crew to Earth following normal ISS crew rotation) - - tether them together and spend 24 or 48 or 72 hours doing tethered flight manuevers before normal re-entry.

Would people be in the Soyuz at the time of the experiment?

If not, where are they?

I always thought that any returning Soyuz was filled with returning crew. So they return them to Earth empty?

Bill White · 2003-04-25 10:27:01

Would people be in the Soyuz at the time of the experiment? If not, where are they?

Well, I expect they will be flying the Soyuz.

We start with slow revolutions, of course, to maintain control and schedule the crew rotation to have a good pilot at the controls.

Obviously, the mission planners would need to do extensive flight sims well in advance to calculate the chances of spinning or tumbling in ways that could not be recovered from.

clark · 2003-04-25 10:33:47

Well, I expect they will be flying the Soyuz.

Wouldn't you need fuel to start and then stop the rotation of the craft?

We start with slow revolutions, of course, to maintain control and schedule the crew rotation to have a good pilot at the controls.

What kind of manuevering ability does a Soyuz have? In a worst case scenerio, the tether snaps, and then the Soyuz flies off at the point of the last centrifugal force it experiences in the spin- it could well end up on an outward spiral...

I like this idea in theory, but I think there might be some serious practical considerations that may make this a dead end. How do you recover without fuel?

Bill White · 2003-04-25 11:10:44

What kind of manuevering ability does a Soyuz have? In a worst case scenerio, the tether snaps, and then the Soyuz flies off at the point of the last centrifugal force it experiences in the spin- it could well end up on an outward spiral...
I like this idea in theory, but I think there might be some serious practical considerations that may make this a dead end. How do you recover without fuel?

All of this is necessary "due diligence" beyond my technical capability. My proposal is to solicit sponsors.

Still, one idea would be to rotate on a plane parallel with the Earth's surface.

If the tether snaps the pilot faces at worst a 2 axis spin, not a 3 axis spin and the "crack the whip" effect will not change orbital energy "merely" orbital inclination. This can all be extensively modeled in flight simulators.

Fuel? Sure. Make sure the manuevering thrusters are all fully topped off before hand. Much of the cost of the experiment may be figuring out how to fully fuel the manuevering thrusters. An expert on Soyuz could probably devise a plan either to supplement existing thrusters or provide reserve fuel.

Main engine burns would NOT be necessary, in my amateur opinion.

Remember there is no need to spin up to 1 gee or even 1/2 gee for a first mission. No need to spin up rapidly either. What flight manuevers are attempted are of course limited by available fuel and appropriate safety margins.

Any controlled tethered flight whatsoever would give valuable telemetry and pilot training and give a foundation for further research.

RobertDyck · 2003-04-25 12:58:57

Excellent idea Bill. We did discuss this on an email list (was it the technical task force?) One conclusion was that the systems for Soyuz are designed for zero-G so they might require modification to operate under the artificial gravity of rotation. The Soyuz navigation system is based on a small telescope to sight starts, so that would definitely have to be modified for rotation. (Apollo also used a start-sight telescope.) I have no idea how robust the gyros are on Soyuz.

One interesting thing about my current job is the sensors I am calibrating for the autopilot. It uses solid state gyros; these are vibrating crystals that use Coriolis forces to measure rotational velocity. They have to be integrated to produce current angle. That is a very compact sensor (necessary for an Unmanned Air Vehicle) and very robust, but the integration will amplify even small errors. Those sensors have to be very carefully calibrated, and a more precise sensor would be necessary for a manned vehicle.

The bottom line is that no one has talked to the Russians about this. This is an excellent idea, especially the work to manoeuvre while rotating in tethered flight, but someone has to pay for it.

Bill White · 2003-04-25 13:17:28

Does GPS work in LEO for accurate 3-D positioning? Can GPS be supplemented with other electronic sources and integrated with the gyros for real time nav data?

GPS plus enhanced gyros and other avionic upgrades would seem the largest cost category. Manuevering thrusters need to work during main engine burns, no? That generates gee force, right? But unless we ask a Soyuz guy, i am merely guessing, without the credentials to even guess badly. . .

Might the Mars Society benefit from an attempt to broker funding from various private sources, seeking only favorable publicity for itself? Even if nothing happens very fast?

Discovery Channel could do a program on the entire project. Garmin (they make GPS units) might sponsor part of the
avionics cost if spotlighted on the Discover Channel program. Being a Russian project, European interests might well invest for marketing purposes. etc. . .

Ideas on how to proceed? Isn't controlled tethered flight rather essential to MarsDirect, to combat microgravity?

= = =

Supplement - Check out this article concerning a plan to dock two Soyuz at the ISS as emergency crew return vessels. Twice as many Soyuz to do tether experiements with when they are rotated consistent with the pre-existing schedule. . .

clark · 2003-04-25 14:00:04

I have a question:

Artifical G, as proposed, would take place in LEO, right?

Wouldn't the gravitational effect of Earth prevent the physics of this working out?

I imagine the 'rubbish rocket' flying in orbit around earth, with the Soyuz circiling the 'rubbish rocket'- this would place the Soyuz perpendicular to the plane of the rocket, as well as Earth... or do i have the wrong impression?

RobertDyck · 2003-04-25 14:32:32

The Soyuz spacecraft would rotate on a tether with a Progress spacecraft on the other end as a counter weight. There would be nothing at the centre. The Progress is used to transport supplies to the space station, and after it's empty is filled with garbage to be de-orbited.

The physics of orbit make anything there effectively weightless as long as it isn't large enough to experience differential gravity. A space colony several kilometres long would have to be placed in high orbit to avoid those differentials. We would use a much shorter tether than that, so Earth's gravity wouldn't interfere with artificial gravity.

RobertDyck · 2003-04-27 15:43:45

Does GPS work in LEO for accurate 3-D positioning? Can GPS be supplemented with other electronic sources and integrated with the gyros for real time nav data?

Yes, GPS does work in LEO. I believe it has already been tested.

Manuevering thrusters need to work during main engine burns, no? That generates gee force, right?

Correct. That sounds like the thrusters should work.

Rxke · 2003-11-16 13:00:36

Has there been any following-up on this tethering idea? When the Russians start launching paying customers again, and one of them is a Mark Shuttleworth(sp?) kind of guy, it should be possible to negociate with them to implement the idea. Shuttleworth insisted to do some sciencework himself, and he got away with it. Experiments could be 'simple' (read:small package) like embryonic bonegrowth (not human)... An 'eyes-closed' coordination test, a fruitflies-in-a-box flight pattern recording... Spiderweb building... Fluid mixing behaviour, osmotic behaviour... Of course, it all depends on how long they'd be prepared to operate in tethered mode...

SpaceNut · 2015-10-25 08:52:02

This was one of those shifting text topics and it is now fixed.

Got reading a bit of the initial posts and they were very laid out in what we needed to work on for technology to allow for a Mars mission survival and since we know that they were made a decade ago we can now measure the efforts that Nasa has made towards these items.

GW Johnson · 2015-10-25 11:11:29

NASA's progress-over-the-last-decade scorecard, as suggested by Spacenut

item progress
supple suit zero
artificial gravity zero
personnel-to-orbit some but awfully slow (commercial crew transport)

The MCP suit idea can be enhanced dramatically if you think of the compression garment as nothing but underwear, over which you wear outer protective clothing that deflects hazards and insulates. Your compression underwear is less vulnerable to tears and to getting dirty that way, although it still requires laundering for bodily excretions. Your protective outerwear can be easily laundered and repaired. I think regolith dust contamination inside the habitat can be controlled better, if you strip off the outerwear in the airlock.

If there's anything that could be done by the Mars Society, it's that suit. Such a garment can be developed and tested down here. All you need is a vacuum chamber for the ultimate demo. Otherwise, its compression just balances your breathing gas overpressure for testing out in the atmosphere, just like Paul Webb did in the 60's. No fancy government facilities required.

GW

Last edited by GW Johnson (2015-10-25 11:13:20)

RobertDyck · 2015-10-25 13:41:34

One Mars Society project could be the laundry machine. Developing a laundry machine for ISS is more difficult, but we could develop one for Mars. It would just be an RV washer/dryer combo. For Mars we would reduce weight, for example using aircraft grade titanium alloy for the drum, and aluminum alloy for the case. By "case" I mean the sides, front, back, top, bottom of the appliance. Commercial ones already use LED controls. Power would have to be compatible with spacecraft power system. ISS uses unusual power; high voltage and high frequency AC. And it would need laundry soap compatible with the water recycling system. That would probably be laundry soap rather than detergent.

Some examples of RV washer/dryer combo: here

RobertDyck · 2015-10-25 13:49:01

How do we convince the Russians to try the Soyuz/Progress tether spin thing?

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