OFMM General Discussions Archive

[dougkeenan]

.ini for the NERVA or a .ini for the launcher? the NERVA2 has a DLL already, which compensates CoG shifts.

Is that DLL in the NERVA2.ZIP package?

 

[Izack]

Is that DLL in the NERVA2.ZIP package?

No, it's right here.

Artlav posted it a while back, but no one really wants to go back there and find it.

 

[Columbia42]

.ini for the NERVA or a .ini for the launcher? the NERVA2 has a DLL already, which compensates CoG shifts.

.ini for a NERVA-compatible Ares V launcher. It requires the NERVA2, the NERVA2.dll, and my Ares V addon.

 

[Bj]

http://iaaweb.org/iaa/Scientific Activity/Study Groups/SG Commission 2/sg22/sg22finalreportr.pdf

Wow, quite a few new concepts to go through. I really wish I am taking physics now,

Alright, I was going to ask about if we really needed artificial gravity, but now looking at the consequences of not having artificial gravity, I changed my mind


The article says;

Indeed, the physiologic responses to continuous exposure to anything other than 1 G are unknown.

I wish they never canceled the CAM...

The article goes on to 'Continuous Artificial Gravity Questions.' Maybe this could be a goal of our 'scientific research' on Mars ...


So just making sure I understand Coriolis right, if the astronaut stands/shifts/moves, it alters the feeling of gravity or force dependent on distances from the center, direction of the movement and velocity of the movement.

This is obviously undesirable since the feeling of gravity will change because of the small(er) distances we have to work with, and will cause space sickness.

For the MSS - The maximum long-term spin-rate for producing artificial gravity without critical Coriolis force is 6 rpm, and since I assumed in the hab design that it gets such artificial gravity during Mars-Earth transfer (only short phases of micro-gravity), this means the minimum distance from rotation axis to Hab bottom is 12.6 meters. If we use a longer radius, the differences in artificial gravity become less, and we can use even smaller rotation rates.

Thus a long boom like structure would be optimal in the MSS design. If we want only 10% variance in artificial gravity between top and bottom of the hab, the length would have to be 126 meters...it scales linear.

I am assuming your meaning a station design like on page 14, and I take it you don't think a simple small module where the astronaut can lay in, (say when sleeping for 8 hours a day) so the astronaut will not move and more or less sit in a mummy bag and be mostly immobilized will be suitable for long duration trips, let alone Mars journeys.

The only problems I can foresee, is;
1. Additional fuel for start/stopping rotation
2. Ability to make fast rotations ie, is RCS good enough so we don't spend hours trying to get up to speed?

Side questions:

Where do you find those kind of articles?
I am going from this... how did you figure out those figures? wned:

 

[Bloodworth]

I had a question, and not sure if it has been addressed quite yet.

Are we going to do the mission like the OFSS (mission commander hands off mission, pilot completes mission and turns in mission report, mission commander hands off next assignment...) or are we planning to do this in real time in OFMP?

 

[Izack]

I had a question, and not sure if it has been addressed quite yet.

Are we going to do the mission like the OFSS (mission commander hands off mission, pilot completes mission and turns in mission report, mission commander hands off next assignment...) or are we planning to do this in real time in OFMP?

It looks like we're going to email around a .scn of the mission, and every pilot will do his part before sending it to the next guy. (This post.)
OFSS had IRC coverage. I'd like to include that in this project as well, when we actually get around to flying the mission. There's an MFD for realtime communication with the pilot.
I've looked at OFMP, and it looks too darned complex for me to figure out.

 

[Pablo49]

I doubt we would email the .scn around. Probably just post them in a thread in the group forum. And IRC coverage is optional of course, depending on the pilot. Again, we aren't anywhere near that point yet, once we have missions, we can discuss how to preform them.

 

[Bloodworth]

Thank you, was just wondering. I'm good with it either way.

 

[Izack]

Yes, I'd like to put off any further decisions on these things until we arrive at that part of the plan.
As it is, I'm pooped for tonight, and much of tomorrow (which I have off, w00t.) I'll probably post some pictures of the cargo meshes (a basic 1.3m^3 cube, and label and a little Martian weathering if I get around to it. No promises yet )
After that, I'll start messing around with launching the Ares V. I need to practice up before construction starts (if and when, of course.)

 

[Urwumpe]

Side questions:

Where do you find those kind of articles?
I am going from this... how did you figure out those figures? wned:

(1)Simple: Google. I just ask it the right questions.

(2)Simple:

I see cross product.
I remember cross product is orthogonal to the plane spanned by the two vectors, and has the magnitude of the surface area of the parallelogram spanned between the two vectors. (simple geometry)

Omega is the angular velocity vector, in radians per second of the rotating system.
v is the particle velocity in the rotating system (eg, you moving relative to the rotating surface of Earth).

The cross product reaches maximal magnitude if both vectors are orthogonal. So, this means the coriolis force is maximal of the particle velocity vector in the rotating system is orthogonal to the angular velocity vector of the rotating system: If you move radially or parallel to the main rotation axis. It is zero if both vectors are parallel or antiparallel: If you move tangentially to the rotating system.

 

[Wolfer]

A bit off topic, but just to let you folks know. Due to real life constraints I will be away from Orbiter until the end of June approximately. Hence I wont be able to really participate in the project anymore. Otherwise I hope this project succeeds and wish you all good luck.

 

[Bj]

I see cross product.
I remember cross product is orthogonal to the plane spanned by the two vectors, and has the magnitude of the surface area of the parallelogram spanned between the two vectors. (simple geometry)

Omega is the angular velocity vector, in radians per second of the rotating system.
v is the particle velocity in the rotating system (eg, you moving relative to the rotating surface of Earth).

The cross product reaches maximal magnitude if both vectors are orthogonal. So, this means the coriolis force is maximal of the particle velocity vector in the rotating system is orthogonal to the angular velocity vector of the rotating system: If you move radially or parallel to the main rotation axis. It is zero if both vectors are parallel or antiparallel: If you move tangentially to the rotating system.

wned:

ok while I soak that in...

We have the ship design for simulating gravity.

Another thing to think about is radiation, for both being on Mars, and en route to/from. Other than putting lead all around a capsule or some other radiation shield material, I saw these;

http://www.barringer1.com/mil_files/NASA-SP-8054.pdf

http://science.nasa.gov/science-news/science-at-nasa/2005/24jun_electrostatics/

Think this 'force field for astronautics' is plausible? Or what other methods of radiation protection are we offering? ...or are we going to worry about it at all?

Next, we have several months on Mars, what science experiments are we going to be doing there? Since our stay is so long, we can be doing quite a few simulated experiments I imagine. We already have the idea of sampling soil and bring back samples in form of elements. Any other ideas? (please realistic experiments)

I will be away from Orbiter until the end of June approximately.

We might just be starting by then... :thumbup:

 

[Izack]

A bit off topic, but just to let you folks know. Due to real life constraints I will be away from Orbiter until the end of June approximately. Hence I wont be able to really participate in the project anymore. Otherwise I hope this project succeeds and wish you all good luck.

I'm sorry to hear that, Wolfer.
But as Bj said, it may not even have started by then...
If it has, it definitely won't be finished. I'm sure you'll get some flight time.

 

[Voyager]

I volunteer to build a space station at about 1000km above Earth to help!

 

[Mojave]

That should be interesting Voyager. Good Luck.

 

[Izack]

I volunteer to build a space station at about 1000km above Earth to help!

Um, I'm not sure how that will help.
Can you explain what this base will do? Also, 1 000km isn't very far, by astronomical standards. The Moon is ~360 000km away when it comes closest (perigee), for instance.

 

[Urwumpe]

I volunteer to build a space station at about 1000km above Earth to help!

We won't stop you, but it is not needed in relation to the Mars Mission Project.

 

[Mojave]

I still can build a landing site with AR81's Surfacebase wizard.

 

[Notebook]

wned:

ok while I soak that in...

We have the ship design for simulating gravity.

Another thing to think about is radiation, for both being on Mars, and en route to/from. Other than putting lead all around a capsule or some other radiation shield material, I saw these;

http://www.barringer1.com/mil_files/NASA-SP-8054.pdf

http://science.nasa.gov/science-news/science-at-nasa/2005/24jun_electrostatics/

Think this 'force field for astronautics' is plausible? Or what other methods of radiation protection are we offering? ...or are we going to worry about it at all?

Next, we have several months on Mars, what science experiments are we going to be doing there? Since our stay is so long, we can be doing quite a few simulated experiments I imagine. We already have the idea of sampling soil and bring back samples in form of elements. Any other ideas? (please realistic experiments)



We might just be starting by then... :thumbup:

Re: The radiation question:

From:
http://www.reactionengines.co.uk/downloads/mars_troy.pdf

A1.2 Radiation Protection
These issues are very complex and require a very detailed study. It may be that the radiation
issues will dictate the age and sex of the crew members. Here the discussion is limited to overall
description of the problem and proposed solutions.

Cosmic Ray Background
The mean particle energy is around 4000MeV/nucleon with an energy range of 102 – 1011 MeV.
The flux is isotropic and constant. This represents a background dose rate of 5 – 12 rem/year,
mainly by secondary radiation generated in the surrounding structure, which would be
acceptable. However there would be about 6 primary ‘hits’/cm3 of tissue per day by heavy nuclei.
Careful shielding with equipment and furnishings would reduce these by an order of magnitude.

Van Allen Belts of Earth
These are very intense belts of electrons and protons trapped in the Earths magnetic field. They
will be traversed four times by the crews on the Troy mission and are not considered to represent
a serious danger.

I'm no expert, but 5-12 rem/year seems low for a Mars trip?

N.

 

[Bj]

Sorry for the delay, I am getting backed up in real life

I'm no expert, but 5-12 rem/year seems low for a Mars trip?
N.

I agree, I found a source:

http://forum.nasaspaceflight.com/index.php?action=dlattach;topic=18139.0;attach=160906

says

1800 mSv over 1095 days which leaves us at 1.64 mSv /day.

Look here http://www.unscear.org/docs/reports/gareport.pdf pg 5

It says 1-10 mSv is yearly normal. --which means 1.64 mSv/day --600 mSv/year (or .6 Sv/year | 60 rem/year)

Though this site http://www.universetoday.com/guide-to-space/mars/mars-radiation/

Says MARIE picked up average of 22 millirads per day(.022 rem/day | 8.03 rem/year)

...but depending on solar events, up to 2,000 millirads /day (2 rem /day || 730/year)

since increased solar activity only happens infrequently, I would say (year);
2x large radiation events
5x smaller radiation events

8.03 + 4 + .5 = 12.5 rem /year.


PG 4 states that blood forming organs (the most limiting) - 50 rem/year is max.

I think, given that we are always exposed to radiation (though small amounts) and that there are things like solar flares and whatever that cause huge changes in the emitted radiation levels, we can have the entire habital area covered in aluminum or polyethylene, then a 'lifeboat' module covered in radiation 'tiles' similar to the Shuttles HRSI tiles.

-----------

OK now I am a little unsure of exactly how much radiation you will get a day in deep space, but one thing is for sure, solar events happen, even the ISS crew had to stay in more protected areas during high radiation dangers. So I think the above proposal of a high strength radiation protection module would be best used for times of high solar activity. Everyone good with this? Or maybe we just assume it is apart of the hab module (just make the hab module have a tile like texture)

Just curious: anyone have any data on the MRE or MARIE measurements? I cannot find them anywhere directly.