High-Level Project Summary
To transform Mars into a habitable place for a year, electricity is key as it can be used to create heat, electrolyze regolith and CO2, etc. Wind turbines or solar panel would quickly be sandblasted or covered in dust by the Mars dust storms, making them unsuitable for Mars. With MarsElectric, we create electricity via thermoelectric effects using temperature differences. We then use the electricity generated using the MarsElectric device, to isolate metals and generate the heat that enable the creation of necessary material such as replacement parts, metal tools or even complex polymers that can be used to build items such as soft surfaces for the habitat. All this is done by 3D printers.
Link to Final Project
Link to Project "Demo"
Detailed Project Description
Problem
We just landed on Mars and oh-no!! A wheel on our rover just broke! That’s going to severe limit our ability to build some of the instruments we need for our scientific mission — and for the comfort of our habitat — since we won’t be able to easily travel and mine for metals.
Fortunately, our 3D printers are intact so we could possibly print a new wheel. But where can we get the material from? Ideally we would use aluminum. However, all we have is this volcanic basalt rock that makes up the regolith which consists mostly of a mix of magnesium based molecules. However, we can electrolyze the elements of the regolith - which fortunately can be mixed with water to create a brine solution which is liquid in the summer temperature and low atmospheric pressure of Mars.
Seebeck-Effect
We find a silicon deposit which is very useful for making semi-conductors. Our plan is therefore to create a Peltier-effect electricity producing cylinder, the surface of which is heated by the sun and the interior of which is cooled by the wind. The outside of the cylinder is coated by a cement casing brackets at regular intervals, which will be printed using our cement 3D printer. We will then create our semi-conductors as rings of identical dimension: we need equal number of rudimentary n-type and p-type semi-conductor rings, which we make out of the silicates we found. Our first prototype is limited by the amount of silicates that we found on Mars around our habitat so we limit the length of our cylinder to 1 meters and width to 10 cm. In between every n-type and p-type semi-conductors is where an electric current will be generated by the thermoelectric effect of the Peltier-cylinder. So, that’s where we are going to place our regolith brine solution to be reduced into simpler molecules. Because the Peltier-cylinder device will be creating the metals that we will need to create mode Peltier-cylinders, we hope to be able to scale our electricity production many fold. We just need to be patient.
The electrolysis of the brine, the molecule Mg(ClO4)2, will cause several components to be created: Oxygen, which we could release into the habitat, but also some Chlorine dioxide, which will be in liquid form at 30F in the inside of our cylinder and thus we hope to collect and use as a disinfectant. The most important ion we’re hoping to isolate is Mg2+, which will react with other Mg2+ ions and create a magnesium alloy deposit at the bottom of the well.
As an added benefit, we can fill empty wells with a mixture of atmospheric CO2 + H2O to create a polymer that can be used as binding agent.
Wheel Assembly
Since our metal printer can only print 150mm x 100mm x 100mm— and our wheel is 0.5m in diameter— it would not be feasible to 3D print the wheel. Therefore, we use a 3D printed cement mold and melt the Mg to pour into the mold. To melt the Mg we need a furnace, which we print out of regolith-based cement and use the electricity generated in the wells as a source of heat effectively creating an electric arc furnace. Using the same technique we can build tools, such as a wrench. We can also print isolation for our tools which will enable the creation of a primitive soldering iron to attach the wheel to the rover.
Space Agency Data
10 REFERENCES USED (8 FROM NASA, 1 FROM ESA, and 1 FROM SPACE APPS)
FROM SPACE APPS Information about The 3D PRINTING CHALLENGE we tackled to outfit a Mars Habitat:
https://2022.spaceappschallenge.org/challenges/2022-challenges/mars-habitat/details
Design a replacement ROVER WHEEL:
FROM NASA: Originally, the wheels are made of aluminum, with cleats for traction and curved titanium spokes for springy support. Other One full turn of the wheels with no slippage drives the rover 65 inches (1.65 meters)):
https://mars.nasa.gov/mars2020/spacecraft/rover/wheels/#:~:text=Materials%20Made%20of%20aluminum%2C%20with,titanium%20spokes%20for%20springy%20support.&text=Other%20One%20full%20turn%20of,65%20inches%20(1.65%20meters).
Design the infrastructure (ELECTRICITY GENERATORS) needed to build more tools during the 1 year mission and beyond for current and other colonists:
FROM NASA: The exact Mars surface composition discovered so far (rich in Magnesium) is:
https://mars.nasa.gov/MPF/ops/hap_2.jpg.
FROM NASA: “Perchlorate brine electrolyzer operating under simulated Martian surface conditions produces >25× the amount of oxygen produced by the Mars Oxygen In-Situ Resource Utilization Experiment from NASA’s Mars 2020 mission” applied electrolysis on regolithic brine:
https://www.pnas.org/doi/10.1073/pnas.2008613117
FROM NASA: For more PLASTIC FILAMENTS: The atmosphere has 95% CO2 (with a smaller amount of other gases — even oxygen!):
Environmental Differences and Stressors that our 3D-printed PELTIER WIND TUNNEL ELECTRICITY GENERATORS have to survive and thrive in:
FROM ESA: CO2-Rich Atmosphere that is 1% as dense as Earth’s:
https://www.esa.int/ESA_Multimedia/Images/2018/04/Comparing_the_atmospheres_of_Mars_and_Earth#:~:text=Mars%20is%20about%20half%20the,rich%20in%20nitrogen%20and%20oxygen.
FROM NASA: Mars Gravity is 3.75 of Earth’s:
https://mars.nasa.gov/all-about-mars/facts/
FROM NASA: Quakes:
https://www.jpl.nasa.gov/news/nasas-insight-records-monster-quake-on-mars
FROM NASA: Constant Winds in CO2-rich atmosphere 1% of Earths:
https://www.nasa.gov/feature/goddard/the-fact-and-fiction-of-martian-dust-storms
FROM NASA: Dust Storms that could cover Solar Panels:
https://earthobservatory.nasa.gov/images/149926/dusty-differences-between-mars-and-earth
Hackathon Journey
The NASA space apps hackathon is a great source of inspiration every year as it forces us to put ourselves in situations and environments with significant constraints which force us to rethink our interaction with the world around us and come up with creative solutions that can solve problems that can benefit future generations.
Since the exploration of a planet like Mars is the first step toward the further exploration of the galaxy and the creation of an inter-galactic intelligent species, we decided to tackle this challenge. We realized that, if we can engineer our way into living in Mars for 1 year, we can find a way to colonize any other foreign planet. Moreover, 3D printing is an incredible technology and progress is being made at accelerating speeds. With that in mind, we wanted to imagine how we could survive and thrive in Mars for 1 year using 3D printers and the materials at our disposal.
Development of earth relied heavily on energy created by fire. But without oxygen or material to burn, that’s a challenge. We realized therefore that making Mars livable is primarily an energy problem. If we solve that problem, materials transformation becomes a possibility. We considered using wind turbine given the strong winds in Mars but quickly realized that any mechanical moving parts would quickly get covered in electrostatic dust particles and stop moving. Solar panels would have the same problem. On the other hand, the temperature delta in Mars is much larger than on earth: up to 100C differential. This is a significant opportunity for the generation of electricity via the thermo-electric effect.
We came across a science fair project where a student had used the Peltier-tile effect to create a working flashlight that was energized only with the heat of her hand and an aluminum tube to act a conductor. We knew this was our path as well. We researched the materials at our disposal in Mars and came across a research article showing that it is possible to use electrolysis to separate Mg2+ ions from the martian regolith brine - Mg(CL04)2 - which would become our main source of metal for the creation of tools, furniture and the replacement wheel itself. We also realized that we could create a virtuous cycle: the generation of more metal would enable the creation of larger Peltier-based devices, which would eventually enable scaling our efforts.
In terms of the 3D shape, we realized that if we created a hollow cylinder instead of a flat tile, we would still have temperature differential between the parts in the sun and the parts in the shade and could use the wind going through the center to further cause temperature differential as long as we deflected the wind from the surface/hot area. Furthermore, we could orient our cylinder perpendicularly to the sunrise-sunset vector so that its surface would be exposed to direct sunlight all day long. Finally, if we had managed to create enough light reflective metals using this process, we could further increase the surface temperature using the same technology that allows for the creation of sun ovens.
Another opportunity that we realized was that, if we created a means to electrolyze the mars regolith brine, we could also use the same electrolysis to create polymers by reducing the atmospheric CO2 in the presence of water and create creature comforts such as pillow or insulation for tools such as a soldering iron.
We identified another challenge: our metal printer was too small for our wheel so we would have to melt the Mg. Our first option was to print the wheel parts independently and solder them together. But that would create a weaker wheel. What if instead we could melt the Mg and pour it into a mold created using the cement printer? We came across the Heroult electric arc furnace which we borrowed into our solution. We could simply use the electricity generated in our Peltier-like device to add the necessary energy to power one such furnace. Since there is no oxygen on Mars, we would not have to deal with the problem of metal oxidation.
Thus, from the solution to one problem - fixing of our wheel - we could solve many other problems that would allow us to survive and thrive in the Mars environment.
We’d like to thank Technocopia (https://technocopia.org/) for teaching us how to design in TinkerCad, alerting us to the problem of wind turbines on Mars, and for their insights about melting metals on Mars.
References
Design a replacement ROVER WHEEL:
Originally, the wheels are made of aluminum, with cleats for traction and curved titanium spokes for springy support. Other One full turn of the wheels with no slippage drives the rover 65 inches (1.65 meters)):
https://mars.nasa.gov/mars2020/spacecraft/rover/wheels/#:~:text=Materials%20Made%20of%20aluminum%2C%20with,titanium%20spokes%20for%20springy%20support.&text=Other%20One%20full%20turn%20of,65%20inches%20(1.65%20meters).
We chose to design a 3D-print process that includes making a wheel made of Magnesium, from the Magnesium Oxide found in the Martian regolith because the yield strength of the pure metal, as cast, is about 3,000 psi (20 MPa) with tensile strength of 12,000 psi (20 MPa), elongation of 6 per cent, and Brinell hardness of 30. Suitably alloyed magnesium provides material with a wide range of mechanical properties.
(and would set precedent for having more METAL FILAMENT):
Design TOOLS to replace the WHEEL:
We used an easy AutoDesk CAD program (TinkerCad) to sketch things (like wrenches) in:
https://www.tinkercad.com/
Design the infrastructure (ELECTRICITY GENERATORS) needed to build more tools during the 1 year mission and beyond for current and other colonists:
SMALL SCALE WORKING EXAMPLE of Technology behind proposed THERMOELECTRIC PELTIER WIND GENERATORS:
https://www.eeweb.com/hollow-flashlight/
There is “glauconitic-like clay” on Mars (our ceramics base for CEMENT and METAL FILAMENTS for the 3D printers for printing the WIND TUNNEL OUTER SHELL):
https://www.dictionary.com/browse/glauconite
The exact surface composition discovered so far (rich in Magnesium) is:
https://mars.nasa.gov/MPF/ops/hap_2.jpg
Magnesium can be extracted from Magnesium Oxide by Electrolysis and Vacuum Distillation:
https://www.aplustopper.com/analysing-electrolysis-molten-compounds/#:~:text=Electrolysis%20of%20molten%20magnesium%20oxide%3A&text=The%20Mg2%2B%20ions%20move,form%20a%20magnesium%20atom%2C%20Mg.&text=Thus%2C%20magnesium%20metal%20is%20formed%20at%20the%20cathode.
Electric Arc Furnaces --first created in the 1800's -- are hot enough to melt the Magnesium, and are used everywhere from tiny ones in Dentist's offices to massive furnaces in automotive or other industries: https://en.wikipedia.org/wiki/Electric_arc_furnace
“Perchlorate brine electrolyzer operating under simulated Martian surface conditions produces >25× the amount of oxygen produced by the Mars Oxygen In-Situ Resource Utilization Experiment from NASA’s Mars 2020 mission” applied electrolysis on regolithic brine:
https://www.pnas.org/doi/10.1073/pnas.2008613117
For more PLASTIC FILAMENTS:
The atmosphere has 95% CO2 (with a smaller amount of other gases — even oxygen!):
This Carbon means 3D plastic filaments can be made:
https://www.bbcearth.com/news/turning-carbon-emissions-into-plastic
This also means it is able to be harvested for CO2 for extra 3D printer filaments made of CO2NCRETE:
https://www.fabbaloo.com/2016/04/carbon-dioxide-as-3d-printing-material
There is also liquid water under the polar ice to be had:
https://www.space.com/mars-liquid-water-south-pole-subglacial
Environmental Differences and Stressors that our 3D-printed PELTIER WIND TUNNEL ELECTRICITY GENERATORS have to survive and thrive in:
CO2-Rich Atmosphere that is 1% as dense as Earth’s:
https://www.esa.int/ESA_Multimedia/Images/2018/04/Comparing_the_atmospheres_of_Mars_and_Earth#:~:text=Mars%20is%20about%20half%20the,rich%20in%20nitrogen%20and%20oxygen.
Mars Gravity is 3.75 of Earth’s:
https://mars.nasa.gov/all-about-mars/facts/
Quakes:
https://www.jpl.nasa.gov/news/nasas-insight-records-monster-quake-on-mars
Constant Winds in CO2-rich atmosphere 1% of Earths:
https://www.nasa.gov/feature/goddard/the-fact-and-fiction-of-martian-dust-storms
Dust Storms that could cover Solar Panels:
https://earthobservatory.nasa.gov/images/149926/dusty-differences-between-mars-and-earth
Less intense light (Mars is only about 590 W/m2 compared to about 1370 W/m2 at the Earth's surface) that makes it harder for traditional solar panels to collect Energy:
Temperatures on Mars average about -81 degrees F. However, temperatures range from around -220 degrees F. in the wintertime at the poles, to +70 degrees F. over the lower latitudes in the summer:
https://www.weather.gov/fsd/mars
Radiation 24-30 rads or 40-to-50 times the average on on Earth:
https://marspedia.org/Radiation#:~:text=The%20average%20natural%20radiation%20level,times%20the%20average%20on%20Earth.
General Thanks to the Makers in Worcester, MA at: https://technocopia.org
Tags
#hardware #3dprint #mars #peltier #thermoelectric #materials #marselectric #Heroult #magnesium