Moon Rocks Lunar Habitat
Overview
The goal of the lunar habitat design project is to develop a fully functional space base to support the living and working requirements of six astronauts indefinitely. This includes life support systems, power systems, crew systems, communication systems, heating and atmospheric systems, as well as ingress and egress areas. The scope includes utilizing food storage that will store food for three months. The habitat should be designed for a lifespan of no less than thirty years. Ideally, the design will utilize In-Situ Resource Utilization (ISRU) as the primary source of construction materials.
The video below introduces the project and hopefully lets you know what to expect from this web page. Please also watch the video to the right. It serves as a tool to help the viewers of this website get a spacial basis for the lunar lava tubes the habitat will be in.
Spatial Relations Video
Team Members
- Daria Baranoff (Web Master)
- Vincent Casados (Project Owner)
- James Dinius (Thermo-Fluids Lead)
- Rodney Longshaw (Technical Lead)
- Emily McDonald (Scrum Master)
- Adrian Perez (Civil Systems Master)
The Client
- Dr. Charles Reynerson, JPL
Acknowledgements
Project Advisor: Robin Steele
Technical Advisor: Bill Kemp, Donald Rynerson, Laura Kerber, Jason Porter, Derrick Rodregiuez, Atef Elsherbeni, Eric Johnson;
Or email dariabaranoff@mymail.mines.edu
Elevator Pitch
This project incorporated the collaboration of knowledge from civil engineering, electrical engineering, and mechanical engineering. The collaboration of these technical fields led to a design solution for a habitat being placed in a lava tube on the lunar surface. This project is a great starting point to launch into the future expansion of humans from Earth to space. Further implementation of this project could lead to the colonization of the Moon as well as nearby planets such as Mars. This project has shown that engineering could lead society in future space exploration.
If at any point while touring this website you have a question feel free to follow this link to a Zoom Meeting where members of the team will be standing by. If you are looking at this page outside of judging hours please email us at dariabaranoff@mymail.mines.edu
Design Approach
The final project presented by this team has gone through a large variety of iterations and design changes. As the team’s understanding of space travel, the lunar surface, and the astronauts’ needs changed so did the habitat. Calculations were done at every phase of the design procedure to back up any decisions that were made.
The initial three designs that the team came up with are pictured below with brief descriptions.
Initial Design Option 1 Branched Habitat: This habitat consists of a central dome headquarters with smaller dome components branching off of it. Each component is connected by a walking corridor in order to allow for multiple pathways of travel between each component. The number of components is not fixed at eight, making this idea expandable for future research and exploration.
Initial Design Option 2 Double Dome Habitat: This habitat design entails a double-hulled dome consisting of two half-sphere domes connected via trusses. The domes would be constructed of triangular tiles forming a geodesic to aid in ease of robotic construction. These structures are strong, providing high strength for minimal material.
Initial Design Option 3 The Torus (Inflatable Doughnut): An inflatable tube with a lower layer of 3D printed regolith on the bottom in order to increase the stability of the tube and on the outside in order to increase the strength. The torus also features two airlocks on opposite ends of the tube so if there is a breach, the station can be split in two. This design focuses on the economics of lightweight materials.
Combining the designs and then comparing the combined design to the top three base designs was the teams next step. The top three designs all had aspects that benefited the habitat while also having detractions so the team created a combined design. The layout of the combined design being the same as the branched design with the central element being the double dome with multiple levels and the branched segments being inflatables encased in 3D printed regolith for stability and durability. The combined design utilizes the ease of construction of the inflatable tube, the stability of the double dome, and the safety of the branched design. When compared to the individual designs, this design won.
Focusing on the central dome. The team decided to focus exclusively on the central hub dome and it’s geodesic aspects as the client asked us to focus on the minimal design. The branches can be added for later expansion. The central hub dome contains all of the subsystems and should have the ability to be self-sustaining until further expansions can be made with the branches. The central hub dome was originally a geodesic dome made out of space grade aluminium and an inner dome of PVC. This design was explored in depth and featured heavily in the IDR. However as the teams understanding of space travel grew so did the understanding that the weight, price, and difficulty for robotic construction of this aluminium geodesic dome was too high.
Using lunar concrete in the final design. These discoveries brought the team to the conclusion that a better material was needed. After discussing with experts and researching how concrete domes are built on Earth the team decided to move forward with a monolithic dome design built on a mat foundation. Both the foundation and actual building are mostly constructed out of lunar concrete maximising in situ resources utilization and minimizing the cost of shipping up materials. The building plan is discussed in more detail in the design solutions. A risk mitigation table was created and the design was edited to be safer and provide less risk for the shareholders.
Risk Mitigation: To the left, we have a video walkthrough of the risk mitigation matrix that was created for this project. If you understand how a risk matrix is designed, feel free to skip to time 5:00 to just see a scroll threw of the matrix.
This matrix greatly informed many of the decisions made for this project.
Design Solution
SubSystems Overview:
Structural
The team decided on a 4m inner radius concrete dome using the ECLSS life support system with options for expansion after initial construction. The habitable volume of the dome is 122 m3 which is enough volume to house at least six people. The habitat is also able to hold enough consumable supplies to sustain six people for three months. The dome is constructed out of lunar concrete, rebar, and an inflatable air form.
The steps for the construction of the habitat are outlined below.
First, A mat foundation is created out of precast lunar concrete. The specifications for the foundation are in the assembly drawing below. To the right is a simple visual representation of the foundation.
Next, an air form is inflated to create the general dome shape of the habitat.
After the air form, all the other layers go on to the inside of the dome. The video below walks threw each of the layers. Those same layers are detailed below. This video does not have sound.
- Polyurethane insulation is installed inside the air form with epoxy coated rebar sticking out of it.
- A basalt fabric sheet is placed over the polyurethane with the rebar poking through it.
- The first layer of lunar shotcrete is sprayed on top of the fabric, incasing the rebar.
- A layer of rebar cage is installed.
- The second layer of lunar shotcrete is sprayed and the interior finish is applied.
The concrete dome is designed without any inside support columns and is able to support itself. To ensure that the design is structurally stable, the dome design was inputted into SolidWorks and an FEA was conducted under parameters specific to the environment the habitat will be exposed to. The internal pressure of the dome was set to 1 atm and gravity was set to 1/6 of earth. The bottom of the habitat was fully fixed. Then the structure was meshed to the groud so the simulation could be run.
The bright red area indicates the location that is experiencing the greatest deflection. The greatest displacement the concrete dome will experience is 3 millimetres at the corner where the hallway meets the dome. The integrity of the structure will not be compromised due to this displacement. This was further justified by the factor of safety that was found to be 11.7.
Crew Systems
The calculations that have been done for the crew systems include food storage and area of general crew systems. This includes the birthing area, dining area, restroom/ cleaning area, and work out area.
The human water usage is mostly based on astronauts’ needs. The calculations factor in how much water is needed for the astronauts to survive including water consumption and water needed to wash up (50 L/day per astronaut). The calculations also include water expelled (1.5 L/day per astronaut), reused (93%), and waisted by the station (7%). Finally, the calculations include how much surge storage is needed if everyone uses the restroom in one hour (9 L in one hour).
Assuming a 2,000 calorie diet per day the six astronauts will be supplied a total of twelve thousand calories per day. To facilitate this the astronauts will be supplied with MRE’s at a rate of eighteen MRE’s per day. With this assumption, the astronauts will need 540 MRE’s per month. The average size of an MRE is 3” x 12” x 8” and weighs 18 – 26 ounces. The total volume of one MRE is 0.005 meters cubed assuming 540 MRE’s will be needed per month the total volume of storage necessary for this would be 2.549 cubic meters, and in order to store three months worth of food, the habitat needs to have 7.646 cubic meters of space. The total weight of this payload would be 1.194 x 103 kg assuming the max weight of an MRE is 26 ounces.
Emergency
The habitat is separated from Earth, the ISS and all other human life and activity and therefore must be able to handle all emergencies without assistance. This subsystem encompasses, disaster control, medical equipment, low power mode, and air/atmospheric backups allowing the crew to work out a majority of the problems they will face. A majority of the emergency subsystem is the same as on the ISS but communications will be much more limited making telemedicine and other emergency communications less effective and reliable. Therefore emergency equipment was assumed to be more robust for this habitat in comparison to the ISS.
Power
The habitat will be powered using a DC power delivery system. The power system would be able to receive AC or DC power from an outside source. The habitat will have enough AC to DC converters to provide enough DC power to supply the habitat. There would be DC to DC converters to clean up the waveforms as to prolong the life of the machinery supporting the habitat. The power system would also have an emergency mode which would have enough battery capacity to last for 7 days in emergency mode.
Communications
Communication with Earth is imperative to the habitat as it is relying on support from Earth as well as providing scientific data. The communication link will be established with the deep space network via a 3.7m cassegrain antenna. This should provide a data speed of 0.5Mbps which should be more than enough for real time text communication as well as transmitting scientific data. This antenna would be outside of the lava tube and the astronauts would access the antenna through a router which would have a fibre optic cable running to the antenna.
Heating
In order to support life and comfort, our habitat needs a temperature control system. Due to the location in a lava tube, our habitat is exposed to a consistent environmental temperature of -15 C. Since our habitat is not exposed to extreme heat, and machine/waste heat is not extreme, a heat rejection system is not required. Our habitat will be heated via resistive heating and air circulation. Heat sinks for the habitat include radiation via the exposed outer hull and conduction into the ground. For the purposes of this model, the internal temperature was assumed to be a uniform 25 C, and a convection coefficient of 10 W m^-1 K^-1 was assumed between the internal air and inner wall. This results in a required heater power of 1.3 kW.
Atmosphere
The atmosphere of my habitat must be maintained to sustain long term lunar habitation. The habitat will be provided with an earth-type atmosphere consisting of 78% Nitrogen and 21% Oxygen at one ATM of pressure. Our atmospheric systems must filter carbon dioxide, resupply oxygen, and maintain pressure/counteract pressure losses through the hull. The oxygen for our habitat will be stored as water and released via electrolysis. 1.4 m^3 of water will be required for a 3 month supply of oxygen and 450 W of power will be required to run the electrolysis system. The hydrogen released by the electrolysis process will be captured and reacted with carbon dioxide to produce methane and water. The water will be re-fed into the atmospheric system, while the methane is vented to space. Compressed Nitrogen storage of 0.4 m^3 will also be required to maintain atmospheric pressure and composition. Additional compressed oxygen storage of 0.02 m^3 will also be provided to allow repressurization of the habitat in the event of a loss of atmosphere.
Next Steps
In order to bring this design to completion, robust and thorough testing of the various subsystems and their interactions would be required. All of the testing information has been compiled into this V and V matrix below.
VERIFICATION PLAN
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VERIFICATION REPORT
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Subsystem | Test # | Requirements | Test Results | ||||||
Atmospheric System
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1A | Air Storage | Air storage is composed of oxygen, nitrogen, hydrogen, methane and carbon dioxide tanks. The storage of these tanks proves to be a significnt component of living in the habitat as well as preparing for any emergency | ||||||
2A | Atmospheric Monitoring and Emergency Ststem | Atmospheric sensors will be in place to monitor any significant changes to the habitat. The emergency air releases help ensure the safety of the astronauts under any significant danger. | |||||||
3A | Oxygen Production | Oxygen production will be broken down into water tanks and an electrolysis system. | |||||||
Communications
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1B | Deep Space Network |
Communication is significantly important especially in terms of communication between Earth and the Lunar habitat. A 3.7 m cassegrain antenna will ensure optimal commincation between Earth and the habitat without any delays and/or interruptions. Laptops will be utilized with in the habitat for communication between the astronauts.
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2B | Astronauts | ||||||||
Crew Sytems
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1C | Kitchen | Water calcuations included the water usage coming from the kitchen. Food storage has been calculated to ensure that food supplies last the required time until they are restocked. | ||||||
2C | Berthing | Berthing area allows for all neccesary needs: sleeping locations, personal storage and clothing. | |||||||
3C | Exercise | Excersie equipment will be supplied to ensure that the physicality of the astronauts does not deteriorate. | |||||||
4C | Work Area | Work area will be composed of a storage area as well as a research area for further and future exploration of the lunar habitat. | |||||||
5C | Bathroom | Water calculations also include the fixe water usages deriving from bathroom related needs and usages. | |||||||
Emergeny Subsystem
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1D | Medical Equipment | The habitat will have an ultrasound, medical equipment and medicine. | ||||||
2D | Disaster Control Kit | Tools placed in the habitat, fire extinguisher, smoke detectors and tools, will be helpful in disaster prevention. | |||||||
3D | Low Power Mode | Low power mode will be utilized to ensure that optimal power is utilized in the event that a disaster impacts the habitat. | |||||||
4D | Air/Atmosphere | Airlocks and air tacks are significant to utilize if danger impacts the habitat. | |||||||
Heating System
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1E | Heating Equipment | Heaters, blowers and air ducts will be the significant equipment ensuring that optimal heating with in the habitat is achieved. | ||||||
2E | Temperature Control | Temperature sensors and heating controls will help regulate heating usages and ensure that heat usage isnt wasted. | |||||||
3E | Waste Heat | Waste heat will be coming from human body heat as well as mechanical heat. | |||||||
Power
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1F | Consumption |
All power calcultations have conducted to allow for proper consumption and distribution with in the habitat. Power calculations have also been conducted to ensure a 7 days of power in the event that the astronaut team needs to be removed from the habitat.
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2F | Distribution | ||||||||
3F | Emergency | ||||||||
Structural
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1G | Foundation | In depth research and calculations were conducted to develope a foundation given its unique enviornmental surrounding. The high stregth of the basalt allowed for resonable assumptions to be conducted, calculations were developed around these assumptions. | ||||||
2G | Monolithic Dome | The process of developing a monolithic dome was studied carefully to ensure that the process could be replicated inside a lava tube on the moon’s surface. All materials for construction were chosen specifically to ensure structural stability and safety for the astronauts. | |||||||
Water Usage
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1H | Potable Water | Potable water can be used for the ecosystem and human usage. Astronauts will be using the water for hygienic purposes and for further consumption. | ||||||
2H | Grey Water | Grey water can be broken down into two aspects: yellow water and brown water. The yellow water is to be recycled so that water can be utilized to its fullest potential. The brown water is to be disguarded. |
Meet the Team
Daria Baranoff
Daria is a Civil Engineering senior at the Colorado School of Mines. She is interested in construction engineering and has a job in the industry starting in May. On this project she created the building plan and was the website lead.
Vincent Casados
Vincent Casados is a Mechanical Engineer pursuing career working and developing technologies in the United States. On this project he was the project owner and created the majority of the 3D modeling for this project.
James Dinius
James is a Mechanical Engineer getting both his Bachelors and Masters degree from the Colorado School of Mines. He was the Thermal Fuilds lead for this project.
Rodney Longshaw
“Sometimes I wonder why that frisbee is getting bigger, and then it hits me.”
Emily McDonald
Emily is a Mechanical Engineering with interest in Biomedical Engineering, and Aerospace. In this project she was the scrum master and did the majority of the written work for this project.
Adrian Perez
Adrian is a Civil Engineer getting his Bachlors and Masters Degree at the Colorado Shool of Mines. For this project he was the Civil Engineering lead and created the foundation design.