Workshop 2 Group 2 : CONCEPT
The space underground will be inhabited by a crew of 3-6 astronauts on the first mission. Since the duration of a mission to Mars is a minimum of two and a half years and cargo capacity is limited, as mentioned, high reliance on what can be found on the planet is a must. The crew won’t be able to bring, as would normally be the case on Earth, a truck with furniture for kitchen, bedroom and other rooms with them. Thus, we envisioned together that the ‘furniture’ and design of the space based on activity requirements could be done by 3D printing local material. The Voronoi can and will be applied at all scales.
1. At the ‘architectural scale’ it will inform the subdivision of spaces. Thus, a cell corresponds to a room, a lab, or a gathering area. This will be built by 3d printing on site regolith concrete.
2. At the ‘structural’ scale, a large lattice of Voronoi cells will be informed by the structural stresses analyzed. Thus the cells are constructed in such a way as to provide most support in the regions of high compression and tension. Within the Voronoi logic, this involves also the fact of having one to multiple vertical layers where needed. Also 3d printed with regolith concrete.
3. At the ‘interior’ scale, smaller cells will create subdivisions in the wall for instance which may serve as storage spaces (equipment, books, clothing etc.) or supporting structures for other equipment (bed, chairs, desks as lab equipment).
4. Finally, the last, most internal ‘layer’ of cells will have the characteristic of enriching the quality of the surface. This will contribute to the acoustic behavior of the various spaces. It will be 3d printed using the silicates found on site, and will act as an inflatable which isolates the pressurized environment from the outside Martian atmosphere.
In this habitat, horizontal and vertical structures are necessary to support the masses, and create rooms. The Voronoi cells could act as rooms walls, on which insulating inflatable material will be printed. Each room has its own membrane. In this case, if one room fails, the rest of the system will be safe. The Voronoi system is open for expansion, corresponding to the need to accommodate a larger human crew. When more astronauts join Mars, the robots will continue the excavation process and create more living modules.
1. The first mission arriving on Mars will most probably not involve humans being on-site, but equipment and a number of robots (a swarm) who will perform the work. After the land has been mapped, the robots will start excavating the Mars regolith and as the excavation proceeds, reinforce the walls. Once the excavation and reinforcement have been realized, a second mapping will be done, this time of the newly built underground interior.
2. A structural analysis will be performed of the excavated interior
3. A cloud point will be created to inform the 3d Voronoi. Based on the four scales previously explained, there will be variation in the density of the points.
4. Thickening the wall. After the process of excavation has been completed (corresponding to milling the Mars regolith) according to the use, the surface of the Martian regolith will be reinforced by 3d printing the Voronoi structure. Thickening the wall where necessary means that some of the furniture will be somehow extruded from the wall and structurally a part of it).
The inclusion of the Melissa Life Support System
In order to ensure livability of the interiors on Mars, the space needs to be pressurized and supplied consistently with fresh oxygen as well as a way to evacuate carbon dioxide (ventilation system). This proposal considers the speculative extraction and use of on-site silicates to 3d print an inflatable structure at the inside of the Voronoi-reinforcing Mars regolith. The Melissa central system (the hardware components which help filter the air, water, and biowaste) will be situated within this Martian habit, within a dedicated room, which will itself be insulated by a pressurized inflatable. This is because once the Martian home is inhabited, the Life Support System will need monitoring and being able to operate it in normal conditions instead of wearing a cumbersome space suit is more convenient. Next to the inhabited spaces, the astronauts will also have a greenhouse to supply them with fresh crops.
Milling – this robotic process corresponds to the excavation of the Martian regolith. It will be done in a spiraling movement. The challenge that needs further research is how to find with the robot the point on the surface from which to mill, and the consequences of this process. The spiraling pattern is considering a topological excavation, meaning that the robot will be operating on a limited patch. The difficulty in the milling process will be the determination of points where the robot starts to operate. The milling follows the Voronoi pattern, excavate a little part and then reinforce it with concrete. First, excess mass is excavated and then the excavation becomes more detailed following the Voronoi pattern.
If one robot does the milling, the rover needs to travel that path multiple times before it is fully excavated. A rover milling robot might be able to excavate a depth of five centimeters at a time for instance.
Excavating the whole at once in a linear fashion would be more problematic, because of the possibility of structural collapse.
In this case milling and the additive part are a continuous and almost simultaneous process. A swarm of robots will be excavating a small region, a second group will bring the Martian concrete on site, and a third group will follow through with the 3d printing path. The process of additively constructing the Voronoi structure will depend on the temperature and speed of the robots, since the material needs time to harden.
There will be a collaboration between rovers on site, which needs to be programmed, to avoid collision as well as to encourage smooth logistics: sending the specific workforce where necessary. The life support layer (with acoustic properties), or in other words the inflatable, will be printed at the very end in order to avoid its contamination with undesired material.
While there will be no human on site to control the process, we propose a creative model for supervising the process. The same script used on Mars will be used in an Earth laboratory. A similar environment will be built in a laboratory and the two construction processes will take place simultaneously, such that, problems encountered in the Earth laboratory can help predict and make adjustments to the script. Furthermore, the 1:1 prototype will serve further the purpose of environment for experiments, such as repairing damaged parts of the wall, optimizing space use, analogue crews training for Mars missions.