Author Topic: Mars One/Paragon Exploration Suit  (Read 4099 times)

Offline Chris Bergin

Mars One/Paragon Exploration Suit
« on: 11/15/2016 12:25 PM »
Mars One release:

>We're pleased to release an independent Conceptual Design Assessment of Mars One's Surface Exploration Suit (SES) by Paragon Space Development Corporation. It includes the soft-goods and hardware associated with the Pressure Suit and the Portable Life Support System (PLSS) that provides the necessary functions for humans to survive in the pressure suit when outside the habitat. Mars One will use this initial conceptual design assessment to update and further develop its mission design of establishing a permanent human settlement on Mars.<

Pretty meaty document:

http://www.mars-one.com/images/uploads/807300008B_Mars_One_SES_Conceptual_Design_-_Public_Release.pdf

Offline Lar

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Re: Mars One/Paragon Exploration Suit
« Reply #1 on: 11/15/2016 03:55 PM »
Any idea with how this squares with work SpaceX has done? Paragon is a supplier to them as well I thought? Is this work reusable? (I am a big Mars One skeptic but anything they do that actually advances TRL I applaud)
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Online high road

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Re: Mars One/Paragon Exploration Suit
« Reply #2 on: 11/16/2016 10:09 AM »
Well, SpaceX will want their astronauts to leave the ITS at some point during their stay on Mars, won't they? And they're only developing the transporation system. So this will be quite useful for them as well. Assuming they don't want to develop counterpressure suits by themselves just because of an expected higher dexterity, I see no compelling reason why they would not go along with this design.

Skimming the document, I see Paragon is going for a suit pressure between .29 and .44 atm. So no 1 atm stuff like in 'the martian'. Which means ITS/MO module internal pressure would have the same pressure, in order to avoid having to spend too much time decompressing. Helps with quick intervention in a crisis as well.

EVAs limited to 8 hours. Donning and Doffing between ten and thirty minutes (unassisted). Now that would be great. Still somewhat longish in crisis situations, but quite a lot better than what sceptics (like me) expected.

I don't know if it's because this is a work in progress or something I missed, but first they say the suit might or might not use an external suit port, but later on page 16 they will reenter anyways to swap out consumables (no mention of doing this via a suitport), while somewhere in between I read consumables will be limited, suggested to a single EVA.

The suits are apparantly meant to last quite long: 7.5 years on average if they would be in use around the clock. Or does that include down time?

Upper size limit 95th percentile of the American male. This struck me as funny, considering MO is Dutch and their 95th percentile is considerably taller than that.

They're going for classic pressure suits, not counterpressure suits. The biggest impact of this is that we now have an idea of the dexterity astronauts have to use ITS's crane system (if that's still the expected route, I've stopped following the exchange of guesses), ladders, rovers, and whatever equipment they would like to bring.

How about using a few of these for tests in the MDRS? Inflate them to .29-.44 bar above sea level and invert potential decompression cycles (or pressurize the habitat accordingly). That would go a long way in adding more realism to the simulations. Other realistic systems could be added as the design continuous to be refined.

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Re: Mars One/Paragon Exploration Suit
« Reply #3 on: 11/17/2016 11:11 AM »
Sooo, nobody's touching this with a ten foot pole eh? I can't help but wonder whether that's because there's Mars One in the title and that makes it unreliable, or because actual studies about developing tech to go to Mars always put a damper on all that enthousiasm, due to the lack of CGI. Or maybe even because nobody likes it when the unpopular candidate shows they're really paying somebody to do basic research ;-)

Having read the entire text now, I've got one more big question for the Paragon people: There are several mentions about Martian dust being potentially harmful to the crew, yet this is not mentioned in the parts about ingress and egress, or the potential follow up study for a suitport. But that's got to be a big consideration? Dust clinging to the suit port can be blasted away with pressurized (Martian) air, much more easily and effectively than cleaning the entire surface of a suit while in an airlock.

Great bit about Martian dust deteriorating the suits. The only data available data shows considerable wear in three effing days, quite short of the 7.5 years mentioned earlier. And nobody's doing any research with better Mars dust simulant to see how alternative materials cope. I guess the same goes for counterpressure suits, which is probably the reason they aren't even mentioned in this analysis. Symptomatic of how far we actually are from sending people 'to stay' and be 'self sustaining' without having a clue how difficult mundane tasks become over there.

Offline Hanelyp

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Re: Mars One/Paragon Exploration Suit
« Reply #4 on: 11/17/2016 06:37 PM »
Skinning the doc I see a lot of requirement spec and very little actual design.

Online MikeAtkinson

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Re: Mars One/Paragon Exploration Suit
« Reply #5 on: 11/17/2016 07:43 PM »
 
Mars One release:
http://www.mars-one.com/images/uploads/807300008B_Mars_One_SES_Conceptual_Design_-_Public_Release.pdf

The 250 SEA (surface excursion activity) goal seems the most difficult. It will drive lots of expensive testing.

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Re: Mars One/Paragon Exploration Suit
« Reply #6 on: 11/18/2016 06:53 AM »
Skinning the doc I see a lot of requirement spec and very little actual design.

Towards the end there are a few suggested subsystems.

This is what the first stage of development looks like: make sure you've got a good idea about all the requirements and interactions with other systems, so every system can in fact interact with each other in all the required ways, and having a basic idea about how you will actually test if these requirements are met. Every next stage of development costs increasing amounts of money, so you don't want to end up with incompatible systems late in the game. And MO doesn't have money to pay for any complete research programme anyway.

One of the conclusions is that there is still basic research to be done that isn't even being planned by anyone. Research that, at the worst case, reduces the operational lifetime of the system from several years to a couple of days. That's a pretty important conclusion to draw early on.

A second important conclusion are the gloves. Any system that might need to be repaired outside the pressurized areas, will either need a separate research project for a new generation of space gloves, to be integrated in a .25 to .44 atm pressurized suit, or will need to be repaired by the clumsy gloves of todays space suits. Impact on the mass of said systems is guaranteed.

Considering I never expected MO to have enough money to actually pay for any development, the thing I get excited about is having a concise list of requirements that new and promising technology, like counterpressure suits, must comply to. So if anyone comes up with a 'gamechanging' technology, we can check the boxes instead of going through endless debates of whether or not each requirement is necessary based on our assumptions about the other systems it needs to interact with. For all you guys that want ITS to go to Mars in the 2020's, these are your constraints. The more experimental tech, the further it gets pushed out.

Mars One release:
http://www.mars-one.com/images/uploads/807300008B_Mars_One_SES_Conceptual_Design_-_Public_Release.pdf

The 250 SEA (surface excursion activity) goal seems the most difficult. It will drive lots of expensive testing.

Especially considering that one of the conclusions is that even the test bed itself still has to be developed. NASA is testing suits for the moon, not Mars.
« Last Edit: 11/18/2016 06:56 AM by high road »

Online meberbs

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Re: Mars One/Paragon Exploration Suit
« Reply #7 on: 11/18/2016 07:40 AM »
Any idea with how this squares with work SpaceX has done? Paragon is a supplier to them as well I thought? Is this work reusable? (I am a big Mars One skeptic but anything they do that actually advances TRL I applaud)

I don't know exactly what Paragon may be doing with SpaceX, but I thought SpaceX was doing its spacesuits all in house. It would be great if some of this can be reused. Since this is a public release, and I don't see any restrictive labels, SpaceX at a minimum could use this to compare with their own requirement set and design. The revision log indicates that there may be a non-public version that was more detailed, but export controlled.

This document in and of itself is primarily a requirements document and conceptual design, which I believe puts it somewhere around TRL2 (This may not be an appropriate way to apply TRL though). To the extent that existing spacesuit designs have been tested and used, I think most of the subsystems really are around TRL 4 - TRL 7.

There are many issues I see with Mars One's plan (I think they have about 6 months left to get LM under contract for the 2020 lander based on the last time around, or it will have to be delayed 2 years - again), but I agree that them funding studies like this is helpful.

Offline ChrisWilson68

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Re: Mars One/Paragon Exploration Suit
« Reply #8 on: 11/18/2016 08:20 AM »
Well, SpaceX will want their astronauts to leave the ITS at some point during their stay on Mars, won't they? And they're only developing the transporation system.

Who said they won't develop anything but the transportation system?

SpaceX isn't just going to develop the transport system and say, "Well, we're done now.  Lets wait to start launching people to Mars until someone else comes along and builds habs, power systems, suits, etc. for a Mars base."

SpaceX will be paying for everything in their colonization effort, at least for the forseable future.  They may or may not build the suits in-house (which is what they're doing for the suits to be worn by NASA astronauts flying to ISS aboard Dragon 2), but if they're not, they'll be paying someone else to build them, and they'll be built to SpaceX specs.

So this will be quite useful for them as well. Assuming they don't want to develop counterpressure suits by themselves just because of an expected higher dexterity, I see no compelling reason why they would not go along with this design.

The cost of this conceptual study is insignificant compared to the importance of Mars suits in their plans.  I can't see any good reason SpaceX would follow the plan laid out in this conceptual study, and many reasons they would not.

Skimming the document, I see Paragon is going for a suit pressure between .29 and .44 atm. So no 1 atm stuff like in 'the martian'. Which means ITS/MO module internal pressure would have the same pressure, in order to avoid having to spend too much time decompressing. Helps with quick intervention in a crisis as well.

They're going for classic pressure suits, not counterpressure suits. The biggest impact of this is that we now have an idea of the dexterity astronauts have to use ITS's crane system (if that's still the expected route, I've stopped following the exchange of guesses), ladders, rovers, and whatever equipment they would like to bring.

Wow, you're drawing conclusions about ITS based on a conceptual study of a suit for a competing Mars program.

There's no way SpaceX decides the design of ITS cranes or the pressure of the atmosphere within ITS based on a conceptual study based on Mars One requirements.  If there's anything we know about SpaceX, it's that they have their own ideas and don't blindly follow what anyone else thinks is a good idea.


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Re: Mars One/Paragon Exploration Suit
« Reply #9 on: 11/18/2016 09:17 AM »
Well, SpaceX will want their astronauts to leave the ITS at some point during their stay on Mars, won't they? And they're only developing the transporation system.

Wow, you're drawing conclusions about ITS based on a conceptual study of a suit for a competing Mars program.

There's no way SpaceX decides the design of ITS cranes or the pressure of the atmosphere within ITS based on a conceptual study based on Mars One requirements.  If there's anything we know about SpaceX, it's that they have their own ideas and don't blindly follow what anyone else thinks is a good idea.

Well, most people agree that ITS is too expensive for SpaceX to fund by themselves. So tacking on 'developing Mars suits' (which are not the same as flight or space suits), 'developing Mars habitats', 'developing Mars ECLSS' (which has a different 'optimal' design for permanent settlement on Mars than for interplanetary travel) etc, will add a lot of extra costs. I assume, completely unfounded, that SpaceX will at some point need some other party to pay for something too. And who foots the bill, sets the design constraints. And I'm assuming again, founded only by years of experience, that those other people will not add considerably more money to their development programme only to cater to SpaceX.

My assumption that Paragon made similar (although probably not fully identical) suggestions to SpaceX, as it was previously suggested that they're talking to SpaceX as well, is that their suggestion does not seem to 'optimal' for MO's 'go to stay' plans. Waaay to clumsy to do some of the more magical stuff. What I see here is a set of requirements for a space suit development programme achievable somewhere in the 2020's rather than the 2030's or 2040's. Which is what SpaceX needs as well, if they want to land ITS in that timeframe. So no promising futuristic tech that's 'absolutely required'.

Offline Triptych

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Re: Mars One/Paragon Exploration Suit
« Reply #10 on: 12/27/2016 03:17 PM »
Well, SpaceX will want their astronauts to leave the ITS at some point during their stay on Mars, won't they? And they're only developing the transporation system. So this will be quite useful for them as well. Assuming they don't want to develop counterpressure suits by themselves just because of an expected higher dexterity, I see no compelling reason why they would not go along with this design.

Skimming the document, I see Paragon is going for a suit pressure between .29 and .44 atm. So no 1 atm stuff like in 'the martian'. Which means ITS/MO module internal pressure would have the same pressure, in order to avoid having to spend too much time decompressing. Helps with quick intervention in a crisis as well.

EVAs limited to 8 hours. Donning and Doffing between ten and thirty minutes (unassisted). Now that would be great. Still somewhat longish in crisis situations, but quite a lot better than what sceptics (like me) expected.

I don't know if it's because this is a work in progress or something I missed, but first they say the suit might or might not use an external suit port, but later on page 16 they will reenter anyways to swap out consumables (no mention of doing this via a suitport), while somewhere in between I read consumables will be limited, suggested to a single EVA.

The suits are apparantly meant to last quite long: 7.5 years on average if they would be in use around the clock. Or does that include down time?

Upper size limit 95th percentile of the American male. This struck me as funny, considering MO is Dutch and their 95th percentile is considerably taller than that.

They're going for classic pressure suits, not counterpressure suits. The biggest impact of this is that we now have an idea of the dexterity astronauts have to use ITS's crane system (if that's still the expected route, I've stopped following the exchange of guesses), ladders, rovers, and whatever equipment they would like to bring.

How about using a few of these for tests in the MDRS? Inflate them to .29-.44 bar above sea level and invert potential decompression cycles (or pressurize the habitat accordingly). That would go a long way in adding more realism to the simulations. Other realistic systems could be added as the design continuous to be refined.

I read at the atomic rockets site that if you attempt to put a high pressure atmosphere in a flexible suit you would blow up like a starfish and be unable to move. If you want to use high pressure for EVA suits then it would have to be a rigid design. This is what left me scratching my head when reading The Martian- in the book Watney said he was breathing a nitrogen-oxygen mix, which meant it was high pressure, but his suit seems to be pretty flexible, so I am a little confused on the issue.

Online high road

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Re: Mars One/Paragon Exploration Suit
« Reply #11 on: 12/27/2016 06:01 PM »

What do you mean by 'flexible'? Current space suits are 'flexible'. Movement is laborious, but astronauts do get the job done. Counterpressure suits will be/are also 'flexible'. Space suit basics.

On Mars, even pure oxygen breathing gas needs to be pressurized to 3231% of Martian ambient pressure, unless you've got astronauts working on a lower oxygen intake than on Earth. Any breathing gas would thus be 'high pressure'.

In a commentary to the movie, Andy Weir has said that rapid exit and entry airlocks are a prerequisite for going to Mars. So assuming you want to be in comfortable sea level pressures in the habitat and not decompress for hours every time you go in or out, 1 atmosphere space suits are the way to go.

Offline Triptych

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Re: Mars One/Paragon Exploration Suit
« Reply #12 on: 12/28/2016 06:12 AM »

What do you mean by 'flexible'? Current space suits are 'flexible'. Movement is laborious, but astronauts do get the job done. Counterpressure suits will be/are also 'flexible'. Space suit basics.

Yes, all current suits are the flexible type. And they all use low pressure pure oxygen mix, which means they have to engage in pre-breathing before doing any EVA. They cannot use high pressure mixes because they would blow up like a balloon and be unable to move, as I said.

Quote
On Mars, even pure oxygen breathing gas needs to be pressurized to 3231% of Martian ambient pressure, unless you've got astronauts working on a lower oxygen intake than on Earth. Any breathing gas would thus be 'high pressure'.

In a commentary to the movie, Andy Weir has said that rapid exit and entry airlocks are a prerequisite for going to Mars. So assuming you want to be in comfortable sea level pressures in the habitat and not decompress for hours every time you go in or out, 1 atmosphere space suits are the way to go.
I just don't see how you could use a high pressure mix if your suit isn't rigid, a flexible suit would stiffen up.

This is an example of a rigid space suit:


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Re: Mars One/Paragon Exploration Suit
« Reply #13 on: 12/28/2016 07:26 AM »
Yes, all current suits are the flexible type. And they all use low pressure pure oxygen mix, which means they have to engage in pre-breathing before doing any EVA. They cannot use high pressure mixes because they would blow up like a balloon and be unable to move, as I said.

If you have a standard habitat pressure of half earth sea level pressure no prebreathing is necessary for using a spacesuit.

At least that is what I found scanning scuba diving info. You can halve pressure without encountering problems.

Offline Triptych

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Re: Mars One/Paragon Exploration Suit
« Reply #14 on: 12/28/2016 05:18 PM »
Yes, all current suits are the flexible type. And they all use low pressure pure oxygen mix, which means they have to engage in pre-breathing before doing any EVA. They cannot use high pressure mixes because they would blow up like a balloon and be unable to move, as I said.

If you have a standard habitat pressure of half earth sea level pressure no prebreathing is necessary for using a spacesuit.

At least that is what I found scanning scuba diving info. You can halve pressure without encountering problems.
If you halve the pressure, then you must increase the percentage of oxygen into the habitat's atmosphere. The ISS is at 14.7 psi with a 21% percent oxygen, the rest mostly nitrogen. Increasing the oxygen ratio will create possible fire hazards.

I think its better to design a semi-rigid suit that could handle high pressure gas mixes at around 8 psi, like the Mark III, which would eliminate the need to pre-breathe.

https://en.wikipedia.org/wiki/Mark_III_(space_suit)

Online guckyfan

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Re: Mars One/Paragon Exploration Suit
« Reply #15 on: 12/28/2016 05:24 PM »
There is no need to have full sea level oxygen partial pressure. People live just fine 2km up. Maybe they go for 30% partial oxygen. The fire hazard may be increased somewhat but not seriously.

I very much doubt they will regularly use hard suits. They would be heavy, expensive and uncomfortable. IMO they would rather use flexible suits or in case they are not best for the job use small one person pressurized vehicles with manipulator arms.

Offline Triptych

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Re: Mars One/Paragon Exploration Suit
« Reply #16 on: 12/29/2016 03:16 PM »
I would think for morale and long term health its best the habitats stick with 1 earth atmosphere. At half pressure and low oxygen mix it would bring about the danger of hypoxia, and could lead to the creation of pockets of carbon monoxide, in addition to the increased fire hazard. Let's not forget that it would require a very specialized form of life support system to handle it. Ninety minutes of pre-breathing would be a small price to pay for EVA using flexible suits.

Offline Robotbeat

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Re: Mars One/Paragon Exploration Suit
« Reply #17 on: 12/29/2016 03:34 PM »
1 Earth atmosphere where? How about Denver. Say, 12psi.

End the dominance of the sea levelers!!!

But seriously, full sea level pressure means that you can't afford as high of margins, and you must pre breathe for EVAs or entering lightweight vehicles, and you have a greater risk of the bends in case of rapid decompression or emergency EVAs.

There really is no reason for Mars to be EXACTLY sea level pressure. Even much of Earth isn't.
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Offline Robotbeat

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Re: Mars One/Paragon Exploration Suit
« Reply #18 on: 12/29/2016 03:35 PM »
On a side note, it is possible to increase the oxygen concentration to higher than 21% IF the total pressure is lower. WITHOUT having a higher fire risk than sea level.
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Re: Mars One/Paragon Exploration Suit
« Reply #19 on: 12/29/2016 03:59 PM »
Boy this conversation is getting off the rails. There is a lot of misinformation / misunderstanding happening on this thread.

Most modern suits operate around 4.7 PSI, of which 3.0 PSI is O2 and the remnant is CO2 and water vapor. One atmosphere (1 ATA) is 14.7 PSI. There is ZERO carbon monoxide in there (I assume carbon dioxide is what was meant in a previous post). This low pressure allows for increase in flexibility. However, the partial pressure oxygen (PP O2) is the same, or very close to, as 1 ATA air because the suit is (close to) 100% O2.

Prebreathing is required because you are moving from a gas mix (air) of 79% inert gas to basically 0% inert gas. You need to allow this inert gas (nitrogen) to come out of saturation in your tissues in a controlled manner (decompression).

The comparison to diving and the effects of pressure on the body while diving is of only limited use as the pressure differentials while diving compared to 1 ATA can be very large. I dive in the 10 ATA range - where you have to breath a gas mixture that would be hypoxic at 1 ATA. This is because O2 is toxic at partial pressures exceeding 1.6 ATA (though YMMV based on your physiology etc). None of this is a concern in space where the PP O2 is always going to be <= 1 ATA (<= 14.7 PSI)

I know I've mentioned this is  the past, but for anyone interested in hearing about the effects of decompression sickness, you can check out a presentation I did on my personal experience with DCS here:



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Offline Vultur

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Re: Mars One/Paragon Exploration Suit
« Reply #20 on: 12/31/2016 07:34 PM »
Great bit about Martian dust deteriorating the suits. The only data available data shows considerable wear in three effing days,
3 days? Are you referring to Apollo? Because Lunar dust IIRC is quite different from Mars dust, and significantly worse since the Moon has essentially zero erosion where Mars has some (though still much less than Earth).


Quote
I guess the same goes for counterpressure suits, which is probably the reason they aren't even mentioned in this analysis.

That's sad to see... I'm firmly convinced that counterpressure is the way to go for making working in vacuum/very low pressure environments easy.

1 Earth atmosphere where? How about Denver. Say, 12psi.

End the dominance of the sea levelers!!!

But seriously, full sea level pressure means that you can't afford as high of margins, and you must pre breathe for EVAs or entering lightweight vehicles, and you have a greater risk of the bends in case of rapid decompression or emergency EVAs.

There really is no reason for Mars to be EXACTLY sea level pressure. Even much of Earth isn't.

Yeah, basically nobody has trouble at Denver altitude. Mexico City altitude (~7400 ft., ~11.2 psi) is still totally OK for pretty much everyone - and you just wouldn't send the few people who do have trouble at that elevation.

IIRC 8000 ft. (about 10.9 psi) is where high altitude is really considered to start - that's also the FAA limit for depressurizing airliner cabins.

And Skylab was something like 5 psi, 75% oxygen/25% nitrogen. It would probably have a somewhat higher fire risk... OTOH doesn't the thinner air & zero gravity impede convection and thus tend to inhibit fire?

Online Dalhousie

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Re: Mars One/Paragon Exploration Suit
« Reply #21 on: 01/01/2017 01:09 AM »
The deep for pre-breathe is not due to changing the gas ratios, but the pressure drop. You can breath 100% O2 at 1 atmosphere without a pre-breathe.
« Last Edit: 01/01/2017 01:18 AM by Dalhousie »
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Re: Mars One/Paragon Exploration Suit
« Reply #22 on: 01/04/2017 02:53 PM »
I guess the same goes for counterpressure suits, which is probably the reason they aren't even mentioned in this analysis.

Quote
That's sad to see... I'm firmly convinced that counterpressure is the way to go for making working in vacuum/very low pressure environments easy.

As I got slammed with last year in the discussion on using MCP suits, none of the 'experts' think they will work and "obviously" since no one IS using them then they don't work. Since no 'regular' suit maker is working with them it follows that line of thinking most of the 'new' makers follow the same assumptions with few exceptions. (Off-hand Final Frontier Design, {http://www.finalfrontierdesign.com/} is the only one I'm aware of doing so and with good reason as they won the 2009 NASA Space Suit Glove challenge with an MCP design and a follow on contract to develop the same into a usable glove attachable to a standard pressure suit and continues to pursue a full MCP design) Part of the reason is the most obvious and 'main' customer is NASA and they have set standards which actually preclude MCP use even though they at the same time offer a specific category for MCP designs.

Bottom line though is they won't buy one and it seems neither will anyone else at the present, even if they were offered. This may change as time goes on and exposure/research continues but as this report again points out it's going to be an uphill battle.

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« Last Edit: 01/04/2017 04:18 PM by RanulfC »
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Re: Mars One/Paragon Exploration Suit
« Reply #23 on: 03/16/2017 06:06 AM »

As I got slammed with last year in the discussion on using MCP suits, none of the 'experts' think they will work and "obviously" since no one IS using them then they don't work. Since no 'regular' suit maker is working with them it follows that line of thinking most of the 'new' makers follow the same assumptions with few exceptions. (Off-hand Final Frontier Design, {http://www.finalfrontierdesign.com/} is the only one I'm aware of doing so and with good reason as they won the 2009 NASA Space Suit Glove challenge with an MCP design and a follow on contract to develop the same into a usable glove attachable to a standard pressure suit and continues to pursue a full MCP design) Part of the reason is the most obvious and 'main' customer is NASA and they have set standards which actually preclude MCP use even though they at the same time offer a specific category for MCP designs.

who are these "experts" who don't think MCP will work? 
"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

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