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Oldfart1939 wrote:Reinventing the wheel?
Almost all the concern over radiation hazards is succinctly discussed in Dr. Zubrin's book, "Entering Space."
What he said!
Could I suggest a list of basic books for someone new to Mars?
Amazon books - sponsor the Mars Society
You've just recommended Martyn's terraformation book... to the team that invented the first practical terraformation method.
In case you forgot.
We didn't forget.
Last edited by Lake Matthew Team - Cole (2017-01-03 21:34:38)
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You've just recommended Martyn's terraformation book... to the team that invented the first practical terraformation method.
And who are you, newbie?
Last edited by RobertDyck (2017-01-03 21:51:11)
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Tools
Oldfart1939 wrote:One of the best small pieces of equipment we could consider for transport to Mars to lighten the workload is a small tractor-frontloader known as a Bobcat. Fitted out with a suite of accessories, it would sure make the work easier than digging and moving regolith by hand...
True, but a tractor-drive has limited mobility on rough ground. You'd want a more versatile loader, like the Caterpillar P-5000, for greenhouse construction. Feature demo at the link.
What?
A Bobcat has very good mobility for the intended purposes. On the other hand, a caterpillar or tracked vehicle is an order of magnitude higher maintenance requirement. Trust me--I've owned several hundred thousand dollars of farm implements. A Bobcat is normally a 2 WD front wheels only powered, but that's where the weight being moved is concentrated. A special unit could be constructed by a number of manufacturers to run on methane and oxygen, which will be available at the base. Rocks in the way? Fine, move them with the front loader.
The tracked model you illustrate would be fine, but unnecessarily complicated for the intended usage of greenhouse construction, and moving regolith to fill said greenhouse.
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Lake Matthew Team - Cole wrote:True, but a tractor-drive has limited mobility on rough ground.
Duh!
Last edited by Lake Matthew Team - Cole (2017-01-03 22:16:37)
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Lake Matthew Team - Cole wrote:Tools
Oldfart1939 wrote:One of the best small pieces of equipment we could consider for transport to Mars to lighten the workload is a small tractor-frontloader known as a Bobcat. Fitted out with a suite of accessories, it would sure make the work easier than digging and moving regolith by hand...
True, but a tractor-drive has limited mobility on rough ground. You'd want a more versatile loader, like the Caterpillar P-5000, for greenhouse construction. Feature demo at the link.
What?
A Bobcat has very good mobility for the intended purposes. On the other hand, a caterpillar or tracked vehicle is an order of magnitude higher maintenance requirement. Trust me--I've owned several hundred thousand dollars of farm implements. A Bobcat is normally a 2 WD front wheels only powered, but that's where the weight being moved is concentrated. A special unit could be constructed by a number of manufacturers to run on methane and oxygen, which will be available at the base. Rocks in the way? Fine, move them with the front loader.
The tracked model you illustrate would be fine, but unnecessarily complicated for the intended usage of greenhouse construction, and moving regolith to fill said greenhouse.
Last edited by Lake Matthew Team - Cole (2017-01-03 22:23:01)
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Depends where you want to build. I said I was part of the team for the Mars Homestead Project phase 1 Hillside Settlement. The premise of that project was to build into the side of a hill. Specifically the side of a valley. Instead of piling regolith on top of habitats, the idea was to dig out the side of a hill, build the settlement in the cut, then drive up the hill and push dirt/soil/regolith down onto the habitat. So you never have to lift up, only push down. That makes digging easier. So that requires a Bobcat size loader that can drive up a hill of soil.
Another premise of that project was to find a location with ice. Mid-latitude locations have ice in the side of dried up river valleys. The habitat would be built where there's loose soil so easy to dig, but very close to ice. Hill climbing on loose soil means tracks.
Of course since then members on this forum have convinced me the frozen pack ice on Elysium Planetia is the ideal location. My requirements were: flat/level so easy to land, low altitude so lot of atmosphere for radiation shielding, close to the equator so warm, lots of ice for water, and something interesting for scientists to study. The requirements of equator and ice appeared contradictory, but the frozen pack ice appears to have everything. So now I argue to send an unmanned rover with a drill to confirm there is ice, and if so then that's our location. A plains location (planetia) may be different. The settlement would still require regolith on habitats for shielding. Could a skid-steer loader with wheels get in trouble? Remember Spirit got stuck in loose sand drifts on hard-packed ground. If you dig a pit as source of regolith, that pit may have steep sides of loose soil you could get stuck in.
Again I argue for human habitats to have regolith on the roof, but greenhouses should not. Plants can withstand much more radiation. Plants can thrive in more radiation than Mars. I've argued that growing plants requires soil and sunlight, why would anyone even debate that?
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Re. greenhouse pressures, what are the limits for bees? Obviously the lower gravity will compensate for lower air density somewhat, but they also need oxygen. Would a 400mb pressure be enough, with 30% oxygen? Can we go even lower, especially if we alter the bees (yes, I know the last attempt to modify bees was a disaster...)?
Of course, we could pollinate by hand, but that takes time. Or we could use plants that don't rely on animal pollination?
Use what is abundant and build to last
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There must also be enough atmospheric density for them to be flight-enabled! I've seen bees in the Colorado mountains as high as 10,000 feet msl, and probably even a little higher. There are flowers and raspberry plants to that elevation, and wild strawberries, too.
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Bees are best. Not only are they good pollinators they also make a great set of byproducts.
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Robert-
A wheeled Bobcat could be mobility-enhanced through the following steps: (1) larger diameter wheels; (2) wider tread profile tires; (3) inclusion of a limited-slip differential for power distribution. The basic design is pretty simple, and allowing the front loader bucket the ability to lift the powering wheels off the ground through down pressure would allow an operator or support personnel a chance to fill in any dug-in wheels before proceeding. My John Deere 6400 4-WD tractor had the ability to raise the front wheels totally off the ground using the loader, which enabled a flat tire to be removed and repaired. At a colony or large base, having 2 such units would enable rescue from getting stuck, and was just one reason we had 2 tractors on the ranch.
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There must also be enough atmospheric density for them to be flight-enabled! I've seen bees in the Colorado mountains as high as 10,000 feet msl, and probably even a little higher. There are flowers and raspberry plants to that elevation, and wild strawberries, too.
At 10,000 feet, the air pressure is only ~70 kPa, and the partial pressure of oxygen only ~15 kPa. Given this, it seems bees would be able to survive in a 250-300mb greenhouse, if the oxygen content is high enough, but I don't know how well they'd acclimatise to high CO2. Though since sheep have been able to adapt to 120mb partial pressure CO2, I'd be surprised if it was a problem.
Use what is abundant and build to last
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I've contacted a friend, an Anthropologist, who spent many years in Nepal, and lived at a village at 13,100 feet msl. She published a paper several years ago which was an inventory of plants utilized by the Sherpas in their daily lives. I made an inquiry as to whether or not she encountered honeybees at that altitude, and whether or not they had a supply of honey or had beehives. A similar set of questions could be posed to any visitors to Tibet.
Last edited by Oldfart1939 (2017-01-04 12:33:33)
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http://www.altitude.org/air_pressure.php
http://www.engineeringtoolbox.com/air-a … d_462.html
Earth Altitude with Equivalent Pressure to Mars
■ Hellas Planitia: 1,155 pascals (11.5 millibars)
■ 11.5 millibars ⇒ 30.125 km = 98,350 feet
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Re. greenhouse pressures, what are the limits for bees?
...insects, like plants, can survive low pressure closed-loop ecosystems. Reductions of pressure that can be tolerated by plants can be tolerated by a wide variety of insects and insect life stages. Although many insects possess different respiratory capabilities, most insects can tolerate pressures down to 100 mb and will operate between 200 mb and 1 bar without major loss of function. Between 500 mb and 1000 mb the insects we studied showed no pressure effects at all.
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<100mb?
For all insects studied the pressure below which complete mobility ceased and the insects showed evident signs of respiratory shutoff was found to be quite well defined and reproducible. For example, for Pogonomyrmex spp (harvester ants) this pressure was 30 mb corresponding to an oxygen partial pressure of 6 mb.
6. Millibars. That's... quite low.
Since they used a terrestrial gas mix, 100mb corresponds to 21mb O2 partial pressure. This has Implications. Not just for life support, but for terraforming.
Use what is abundant and build to last
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I really fail to see the rationale for the direction this is heading. The greenhouse atmosphere needs to be human friendly, since this isn't really a plant it and walk away project. Humans should be able to work w/o respiratory gear in place, and outside of a Mars suit. These plants, once they are started, are near priceless; watering and checking the soil moisture is practically an unending process. Periodic pruning of plants helps productivity, simply by removal of what are called, in the gardening community, "suckers." These are shoots which...say on a tomato plant...will never bear a flower or produce a tomato. If the atmosphere is "human-friendly," then bees should have not problems doing their thing, pollinating the plant blooms.
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I really fail to see the rationale for the direction this is heading... If the atmosphere is "human-friendly," then bees should have not problems...
You don't know til you know.
Now we know.
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In creating a Human freindly environment does introduce a higher mass for the structure ( multi-layer transparent with safe protocols, sensors, sealing capability ), more site prep for the structure to stay down with, ground to plant soil isolation from heat sinking process ect....
A safe environment for a greenhouse that uses LEDs and could be shirt sleeve will be in things like a spent cargo capsule...If we are preloading supplies this only makes sense to do as when they are empty its not to be thrown away, we need to reuse as much as possible that we land on mars initally.
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IoT Hydroponics
Btw, IoT hydroponics is actually a thing now. Examples: Fujitsu, BLT Robotics, FlowThings.io, Gro.io.
Gro.io wins the prize for cuddly graphic design, but Fujitsu is doing the more interesting work. Notice how they've used their IoT system to grow produce with "unusually low levels of potassium, a feat only pulled off at one other facility." That sounds like the sort of precision growth that would be very hard to accomplish without IoT hydroponic control.
Update: "Greenhouse Horticulture SaaS"
I see Fujitsu has commercialized their IoT hydroponics as "Greenhouse Horticulture SaaS". Nice presentation of the data and hardware.
Pressing forward with IoT greenhouse automation, Fujitsu has recently inaugurated a new company, Fujitsu Greenhouse Technology Finland:
"Fujitsu Greenhouse Technology Finland, which will begin full-scale production in the first half of fiscal 2017, uses a plant factory equipped with the latest technologies, including the Fujitsu Intelligent Society Solution 'Akisai' Food and Agriculture Cloud, which is Fujitsu’s food and agricultural cloud service, along with fully artificial lighting using LEDs, multi-tier growing trays, and full automation.
Fujitsu and Robbe’s Little Garden aim to grow and deliver a steady, year-round supply of vegetables, such as baby greens and leaf lettuce, in Finland, which has few hours of sunlight during its harsh winter. Fujitsu also aims to package the know-how and cloud services resulting from this business and deploy them throughout the European Union."
Finland isn't Mars of course, but Finnish winter is a bit Mars-ish, especially up north. The Finns handle it with grace, but still, brr. Not kind to wet electronic prototypes.
The new Finnish greenhouse company should give Fujitsu many "lessons learned" for future reference, elsewhere.
Last edited by Lake Matthew Team - Cole (2017-01-17 12:30:58)
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Magic words for the snow bound building is insulation and energy.... if either are not adquate then the greenhouse fails.....
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Lunar, Martian Greenhouses Designed to Mimic Those on Earth
Trough the design and construction of an innovative hydroponic plant growth chamber, the Prototype Lunar Greenhouse is designed to sustain a continuous vegetarian diet for astronauts on distant locations such as the moon or Mars. It employs plants and crop production designed to provide not only food, but air revitalization, water recycling and waste recycling.
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Lovely to see. Some points:
1. Why is oxygenation of water important to this system? Is that something that happens naturally in the soil?
2. They seem to be thinking in term of this being a closed system once it gets going. You can see the advantages but I think with some other attempts at closed systems, there have been issues with mould growth, and threats to human health.
3. Is it possible that NASA are again going for something more complex (and expensive) than it need be.
Lunar, Martian Greenhouses Designed to Mimic Those on Earth
Trough the design and construction of an innovative hydroponic plant growth chamber, the Prototype Lunar Greenhouse is designed to sustain a continuous vegetarian diet for astronauts on distant locations such as the moon or Mars. It employs plants and crop production designed to provide not only food, but air revitalization, water recycling and waste recycling.
Let's Go to Mars...Google on: Fast Track to Mars blogspot.com
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Water is normally oxygenated by falling as rain, flowing down a stream with rocks over an incline or falls, it is something that will slow algea growth and is good for fish if that is part of the food chain. plus aids in mineral desolving.
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Interesting ideas on soil creation. I think a big hurdle on Mars is going to be the 0.2-1% by weight perchlorate compounds in the regolith. That stuff is basically weed killer and is toxic to all animal life. There may be other salts that impair plant growth. Luckily all of these toxins are water soluble and can be removed by dissolving and then freezing. As the perchlorate is a strong oxidising agent it can either be broken down to yield oxygen or reacted with any organics we can find on Mars as a fuel.
Also, we discussed earlier the possibility of covering simple steel frames with regolith in order to create pressurised habitable spaces within depressions like craters. Here is a link to a shape that may be useful.
https://en.wikipedia.org/wiki/Pendentive
As the base has a square cross-section, these units could be stacked together to form continuous spaces. The central dome could have a large sunlight pipe in the middle protruding through the regolith to the surface. If the sunlight pipes have cross-sectional area equal to 50% of total enclosed area, and the area is located at the equator, then the average solar intensity within the habitat will be 750kWh/year. That's about the insolation that Scotland or Northern Canada receive. Enough for crop growth and abundant plant growth if temperatures are kept warm.
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