[1.0.5] TAC Life Support v0.11.2.1 [12Dec]

[Lalwcat]

Could this be easily integrated with the Biomass mod?

http://forum.kerbalspaceprogram.com/threads/53009-0-21-BioMass-Renewable-Bio-Fuel-Modules

The greenhouses already work entirely with it. They use the same resources as TAC.

I've tried them but found them to be a bit overpowered. Maybe I was just not using it correctly, but I found that by just adding a single greenhouse I could sustain 3 kerbals indefinitely in food and oxygen. Water was dropping and would have to be resupplied, since you couldn't even use a water recycler as the greenhouse used it all up.

[yeliabmit]

...the models are just fine, but the default textures are [terrible] yes (sorry TaranisElsu) ...

I think the TAC mod is really great in terms of detail, but I would push back a bit on this point a bit. I started using this mod, but eventually the parts started to seem a bit OP because they seem kind of small for what they purport to represent. I'm using the ELSS life support mod right now mainly because the ELSS parts are bigger and more (realistically) intrusive for what they represent.

[cfds]

Why are the parts too small? The ressources to feed one Kerbin for one day take 3.6 litres of volume (when we assume that O2 is stored at 200 bar and food has a density of about 1). The 1.25m life support container has a volume of 306 litres, 80 rations have a volume of 290 litres. This is at worst slighlty too small since you would need space for pumps an the like, but it is certainly not "not realistically intrusive".

[Read have Read]

Now I thought TAC was using corrected life support mathematics from here, and it does look like at least the volume and consumption is based on those values. It appears, after crunching the numbers, that the tanks for Oxygen and water are heavier than they should be, or at least for the contents of the tanks. With pumps and pressure vessels, it is a reasonable weight that borders on the heavier side. As for volume the tanks also border on the less rather than more for their volume, with Food containers carrying less than the absolute maximum, likely to account for packaging and such.

I find that having an entire service module for ECLSS just to carry 2 days worth of oxygen to be absurd. I am sure ECLSS is great for the Real Solar System crowd where the have double the diameter of rockets (which more than doubles the volume) and the mod already simulates human rates of consumption with lots of technical features. However it does not do food or water!

[jfjohnny5]

I'm using the ELSS life support mod right now

Haven't seen the ELSS mod. Link?

[diomedea]

I think the TAC mod is really great in terms of detail, but I would push back a bit on this point a bit. I started using this mod, but eventually the parts started to seem a bit OP because they seem kind of small for what they purport to represent. I'm using the ELSS life support mod right now mainly because the ELSS parts are bigger and more (realistically) intrusive for what they represent.

One of the great advantages in KSP is the ability to choose which mods are best for one own playstyle.

ECLSS (apart from some awful FPS drops, mainly due to calculating resource expenditure for every single part of every single vessel) has this "peculiarity" of very big sizes with the resources required; that was debated on the ECLSS thread and somebody already observed how hard could be to use it.

TAC LS has different volumes for its resources, but those match with the resource consumption rates being used as a basis for life support. Those consumption rates have been discussed at length, and I reckon in the end they were found to be correct.

I would not say TAC LS is overpowered; but certainly ECLSS makes for a much more difficult game.

[jrandom]

Now I thought TAC was using corrected life support mathematics from here, and it does look like at least the volume and consumption is based on those values. It appears, after crunching the numbers, that the tanks for Oxygen and water are heavier than they should be, or at least for the contents of the tanks. With pumps and pressure vessels, it is a reasonable weight that borders on the heavier side. As for volume the tanks also border on the less rather than more for their volume, with Food containers carrying less than the absolute maximum, likely to account for packaging and such.

I find that having an entire service module for ECLSS just to carry 2 days worth of oxygen to be absurd. I am sure ECLSS is great for the Real Solar System crowd where the have double the diameter of rockets (which more than doubles the volume) and the mod already simulates human rates of consumption with lots of technical features. However it does not do food or water!

I made a basic realism rescale of TACLS for Realism Overhaul, and I was surprised at just how little volume was actually required, compared to the size of the rockets I was sending up. I don't quite remember how this compares to stock TACLS, but you're free to check it out for comparison. (Keep in mind the containers have been rescaled to 0.5, 1, and 2-meter parts and the amounts are based on those volumes.)

ECLSS (at least the last time I checked) was very unrealistic in terms of oxygen volume. The rescale I did above uses compressed (non-liquid) oxygen at 300kg / m^3, which I understand is in line with real-world technologies.

[TaranisElsu]

The number of units per container are kind of arbitrary right now. I made those parts before I worked out the volumes for the various resources. In fact, I am still figuring that out (anyone want to help?). But while the sizes are arbitary, the masses are all correct according to http://en.wikipedia.org/wiki/Life_support_system#Human_physiological_and_metabolic_needs. And in rocket science, size doesn't really matter but mass matters a lot. The extra mass is what requires you to bring extra fuel to get the same dV.

As I linked earlier in the thread, most of my math is here: https://docs.google.com/spreadsheet/ccc?key=0Aioc9ek3XAvwdGNsRlh3OVhlbTFBR3M4RW0zLUNTRFE&usp=sharing

[seanth]

I have been asked to weigh in on the discussion here: http://forum.kerbalspaceprogram.com/threads/61296-Build-a-Centralized-Modder-Unified-Resource-Catalog

What are your opinions? It would mean giving up the convenient 1 unit per Kerbal per day resource consumption rates.

Keep in mind that the actual amount consumed, the mass, would not change. The only thing that would change is the resource display. Kerbals would still need 0.317 kg of Food, 1.798 kg of Water, and 0.429 kg of Oxygen per 24 hours, but it would change to something like 1.798 units (liters) of Water and 1.490 units (liters) of Oxygen per 24 hours instead of 1 unit of Water and 1 unit of Oxygen per 24 hours.

Is this a closed topic? I ask only because I'm putting final touches on a greenhouse and the 1 unit/Kerbal/day for everything is unpossible to accomplish and maintain mass balance. 1 unit O2/Kerbal/day would be a good compromise, but the resulting food/water intake and CO2/waste production will necessarily not be 1 unit/kerbal/day

[seanth]

The number of units per container are kind of arbitrary right now. I made those parts before I worked out the volumes for the various resources. In fact, I am still figuring that out (anyone want to help?).

I'm interested in helping if you'll have me.

[TaranisElsu]

As I linked earlier in the thread, most of my math is here: https://docs.google.com/spreadsheet/ccc?key=0Aioc9ek3XAvwdGNsRlh3OVhlbTFBR3M4RW0zLUNTRFE&usp=sharing

So I did some more work on figuring out the volumes, with the result that I think my containers are only ~13% full! That is not counting packaging or structural volume, or the tank for holding compressed oxygen (at 200 bar/20 MPa/~2900 psi).

Given those calculations, I do not think my containers are too small. If anything, they are too big. Lots of wasted space.

The smallest container is a cylinder with a 0.625 meter radius and 0.25 meter height. The total volume is 0.307 cubic meters or 307 liters (v = pi * r^2 * h). Ten days of supplies is: 3.2 kg of food, 18 kg of water, and 4.3 kg of oxygen. Water is 1 kg / liter and oxygen can be compressed to 0.3 kg / liter. Food, I have no idea . Those add up to ? liters of food, 18 liters of water, and 13.8 liters of oxygen, much much less than the 307 liter volume of the container.

I'm interested in helping if you'll have me.

Please do

[Read have Read]

First thing I see is you have .625, 1.25 and 2.5 metres listed as radius, but from what I can tell, those sizes are Diameters. I measured the regular sized tanks against their diameter and other parts and found them to be .625 radius x .25m high for a volume of .306 cubic metres. The 2.5 metre tanks have a radius of 1.25m and are .5m high with a volume of 2.45 cubic metres

Edited December 24, 2013 by Read have Read

[TaranisElsu]

First thing I see is you have .625, 1.25 and 2.5 metres listed as radius, but from what I can tell, those sizes are Diameters. I measured the regular sized tanks against their diameter and other parts and found them to be .625 radius x .25m high for a volume of .306 cubic metres. The 2.5 metre tanks have a radius of 1.25m and are .5m high with a volume of 2.45 cubic metres

Well, that makes a big difference. Then my containers are 106.1% full.

[Read have Read]

106% is pretty darn close!

So far I have:

306L for reg tank
306 x 4 = 1224L for 1m3
wait, can't, shouldn't hold more than 250L no
1.25m x 1m tall stack holds 1.22 cubic meters, and 1224L is correct
how much is that per day?

Kerbals are 90kg suited, and could be between 15 to 30kg, so the suit is either 3 or 6 times the kerbal inside. An ISS EMU suit and a shuttle MMU weigh around 300 pounds each. That is 3x the weight of a a 200 pound astronaut, and 6 times the weight of a 100 pound astronaut. The heaviest Apollo astronaut was swigert at 86kg, or 180lb, and the lightest was Mattingly, at 62kg or near 120 pounds. Currently TACLS appears to use 30kg kerbalnaut, while the Life support maths post is around 15 when the numbers are halved. Lets keep it simple and say that heavier kerbals means double the consumption rate, and for the purposes of gameplay, it is less trivial if we use the consumption for a 30kg kerbal. If kerbals had varying weights, some fatter and some skinnier, the 30kg number would be the best one.

I can't seem to find any weight or volume for ISS or shuttle meals, but in Life Support Mathematics, the author uses the following:

I've decided that the Humanitarian Daily Ration -- basically a stripped-down civilian form of the MRE -- is a good reference food; it's a single packet that provides 2,200 calories for a single person, has a shelf life of three years, and generally would work well as a typical "space food." [13] A case of 10 HDRs provides 22,000 calories, weighs 11 kilograms, and takes up 0.03 cubic meters of volume [14], meaning that one cubic meter of HDRs provides 733,260 kilocalories and weighs 366.63 kilograms.

This results in Food being half the weight of water, but a 60% more volume.

Currently in game, 4 food tanks provide the same 960 days of food as they do water, with one being half a ton and the other at 2 tons. If food is less dense then they are, then Food tanks should have slightly less mass, but also hold about half of what they do. Food is overlooked by all other Life support systems, but is something that can't be regenerated at all and takes up more space than anything else, this is balanced by the fact that the other resources are dense and do not take as much volume to carry, especially with generators.

Edited December 25, 2013 by Read have Read

[TaranisElsu]

Kerbals are 90kg suited, and could be between 15 to 30kg, so the suit is either 3 or 6 times the kerbal inside. An ISS EMU suit and a shuttle MMU weigh around 300 pounds each. That is 3x the weight of a a 200 pound astronaut, and 6 times the weight of a 100 pound astronaut. The heaviest Apollo astronaut was swigert at 86kg, or 180lb, and the lightest was Mattingly, at 62kg or near 120 pounds. Currently TACLS appears to use 30kg kerbalnaut, while the Life support maths post is around 15 when the numbers are halved. Lets keep it simple and say that heavier kerbals means double the consumption rate, and for the purposes of gameplay, it is less trivial if we use the consumption for a 30kg kerbal. If kerbals had varying weights, some fatter and some skinnier, the 30kg number would be the best one.

I did similar math and came to the conclusion that Kerbals weight ~32.5 kg on average. Plugged that into the equation here: http://equation-of-the-month.blogspot.it/2012/06/kleiber-law.html, and came up with the ~51% consumption rate for Kerbals.

[TaranisElsu]

Well, a quick search turns up that the ISS crew members are assigned approximately 1.8kg of food per day, per person. If kerbals need half that we can round a bit and call it 1kg per kerbal per day. I'm not sure what volume that should require, however. It just becomes a matter of determining what density the food should be. We know the mass (1kg per kerbal-day) so the density allows us to derive the volume needed. From that we can either determine how much the current containers can actually hold and what their mass should be, or we can determine what volume the containers need to be to hold the desired mass of food.

Assuming the same (inefficient) packaging that we use here on Earth, then approximately 75% of the waste mass will be food packaging (the wiki page showed ~65% to 90% waste was food packaging on various missions). Not sure how that would play into the mod, however. It might be easier to just gloss over that part.

Do you have a link for that? Because http://en.wikipedia.org/wiki/Life_support_system#Human_physiological_and_metabolic_needs says the crew need 0.62 kg of food per day. It might be a difference between the amount they actually consume and the amount with packaging and inedible bits (orange peels, bones, etc).

I have been thinking of increasing the Food mass and Waste mass by the same amount to represent that.

I feel that the food requirements are a little light as they are.

[nhnifong]

If I were designing a long term mission, I would pack food that contained a minimum of inedible parts (including packaging)

[TaranisElsu]

If I were designing a long term mission, I would pack food that contained a minimum of inedible parts (including packaging)

Agreed, and I think that NASA tries when sending stuff to the ISS. You cannot get rid of all of the packaging though. You need some to preserve it and keep meals separated so the wrong flavors don't mix. I also assume that most packaging should be reusable with a minimal amount of work.

[seanth]

I feel that the food requirements are a little light as they are.

Keep in mind that smaller massed organisms have faster metabolisms, as a rule. Mice and elephants have the same number of heartbeats in a lifetime. But these are pretend aliens, so I don't think things need to nail human metabolic rates exactly.

FWIW, prior to seeing your spreadsheet from when I posted on github, I had worked out similar back-of the envelope numbers. My values are nearly the same as your:

Mass Kerbal (kg): 31.25

Mass Suit (kg): 58.75

Oxygen consumption (kg/86400sec): 0.4234

Water consumption (kg/86400sec): 1.7742

Food consumption (kg/86400sec): 0.3125

Solid waste production (kg/86400sec): 0.0554

Liquid waste production (kg/86400sec): 1.9506

CO2 production (kg/86400): 0.5040

consumption mass is equal to production mass: (0.4234+1.7742+0.3125)=(0.0554+1.9506+0.5040), taking rounding errors into account

I'm embarrassed to say that I then assumed plant respiration would consume 1 kg of biomass in 10,800sec (1 kerbal night. 3 hours) and adjusted all other growth rates from there. I'm going to fix that, but thought it'd be nice if I used the same respiration rate as TACLS

[cfds]

My suggestions are the following:

One kerbal-day of oxygen has a mass of 0.43kg and takes about 1.5l of volume at 200bar. A 1.25m tank fits 160 units and uses 79% of its total volume.

One kerbal-day of water: 1.8l, 160 units would fill 92% of a 1.25m tank. That might be just a bit much, since we would need insulation and structural parts...

I ballparked a kerbal-day of food at about 0.6l (density of 0.5kg/l) and a 1.25 part would carry 400 units easily.

The complete 1.25m lifesupport part can fit 64 units of everything and still keep 18% of its volume for structure and infrastructure.

[kalizec]

One kerbal-day of oxygen has a mass of 0.43kg and takes about 1.5l of volume at 200bar. A 1.25m tank fits 160 units and uses 79% of its total volume.

Don't forget about the reactant necessary for removing the CO2.

[cfds]

Ok, the hexcans are way too full. The standard-sized one has a total volume of about 130l, so it would fit at maximum 80 units of Oxygen instead of 240 and no CO2. Similarily, it should only fit like 64 units of water and perhaps 160 units of food.

Edited December 26, 2013 by cfds

[tabaal2]

My kerbals don't take anny oxygen on EVA and die immedietly? how can i fix this porblem

[TaranisElsu]

My kerbals don't take anny oxygen on EVA and die immedietly? how can i fix this porblem

More information please:

1. Are there any errors in the debug window or the log file? Would you upload the log file to somewhere that I can look at it? Like dropbox or pastebin? You can find the log file at {KSP}/KSP_Data/output_log.txt.
   
2. What mods do you have installed?
   
3. What do you mean "immediately"? They should live for 2 hours after oxygen runs out. Are they really dying instantly? Have you changed any of the settings?
   
4. Can you recreate it reliably? Or did it only happen once? Or with only one ship? What steps can I do to recreate the problem?
   

It really sounds like you have a conflict between some of the mods that you have installed. Try uninstalling some (temporarily move them out of the GameData folder) and see if the issue persists.

[crua9]

I was thinking about getting this mod, but I was wondering something. Is it possible to have some can or something make food? I want to make a few bases on ground and in space, and it would suck to have to send food every few min.

Also, is there a chart or something showing how long a kerbal can last per x amount of food,water, etc ?