The year 2038. After 18 months living and working on the surface of Mars a team of six researchers sits back in the spacecraft and returned to Earth. On the planet there is not a single living soul, but the work here never stops for a minute. Autonomous robots continue the extraction of minerals and deliver them for processing to the factory of chemical synthesis, which was built several years before on Mars for the first time set foot of man. The factory produces from local resources water, oxygen and rocket fuel, routine preparing supplies for the next expedition, which will arrive in two years.
This robotic factory no science fiction. This project, which currently employs several science teams space Agency NASA. One of them, Swamp Works, works at Kennedy Space center in Florida. Officially they developed setting called “system utilization of in situ resources” (ISRU), but the people who are working on it used to call it dust factory, because it recycles the usual dust in rocket fuel. This system will one day allow people to live and work on Mars and also return back again to Earth.
Why do something to synthesize on Mars? Why not just bring all the necessary stuff from the Ground? The problem is the cost of this pleasure. According to some estimates, deliver one kilogram of payload (e.g., fuel) from Earth to Mars — that is, the output of this kilogram into low earth orbit, sending it to Mars, the deceleration of the spacecraft in the orbit of the planet and finally safe landing on the surface – it is required to burn 225 pounds of rocket fuel. The ratio of 225:1 – that more efficiency. While those numbers are typical when using any of the spacecraft. That is, to deliver the same ton of water, oxygen or technical equipment to the Red planet will be required to burn 225 tons of rocket fuel. The only way to save yourself from such costly arithmetic – own production of water, oxygen or fuel on the spot.
Several research and engineering teams at NASA are working to address different aspects of this problem. For example, the team from Swamp Works at Kennedy Space center recently began the Assembly of all the individual modules of the system mining. The installation is an early prototype, but combines all the details that would be required to operate dust-collecting factory.
Long-term plan for NASA focused on the colonization of Mars, but now the Agency has concentrated all its energy and attention on the moon. Thus check the most part of the developed equipment will be first on the lunar surface, which in turn will help to solve all possible problems to avoid them in the future when using the installation on Mars.
Dust and dirt on extraterrestrial cosmic body is called regolith. In a General sense we are talking about volcanic rock, which over millions of years under the influence of various weather conditions turned into a fine powder. On Mars under a layer of corrosive minerals of iron which give the planet its famous reddish hue, lies a thick layer of silicon and oxygen structures, connected with iron, aluminium and magnesium. The production of these materials is a very difficult task, as stocks and the concentration of these substances may vary from one region of the planet to another. Unfortunately, this task is complicated by the low gravity of Mars – digging in such conditions, taking advantage of the mass much more difficult. On Earth for mining we usually use large machines. Their size and weight allow you to exert enough effort in order to “bite” into the ground. Take on Mars such a luxury is absolutely inexcusable. Remember the problem of the cost? Every gram sent to Mars, the price of launch will continue to grow. Therefore, NASA is working on a way to make the extraction of minerals on the red planet using lightweight equipment.
Space excavator. NASA is developing a robotic excavator with two buckets opposite to the drum rotating in opposite to each other direction. This approach will allow the machine to operate in low gravity environments and eliminate the need to put more effort
Meet RASSOR (Regolith Advanced Surface Systems Operations Robot) is an Autonomous earner, designed with one goal – to dig the regolith in low gravity. When developing the RASSOR (pronounced “razor” — from the English “blade”) NASA engineers have paid special attention to his system of actuators. The latter consists of motors, gearboxes and other mechanisms that make up the bulk of the whole setup. Here we use frameless motors, electromagnetic brakes, as well as, among other things, a 3D printed titanium case – all in order to minimize the total weight and volume of the design. As a result, the system has about half less weight than other drives with similar specifications.
For digging RASSOR uses two opposition drum of the bucket, each of which has multiple teeth for gripping material. When moving the unit drum buckets rotate. The drives that hold them, go down and the drums are hollow inside, literally cut off the top layer of the surface regolith. In other words, the processor extracts only the upper layer of material, rather than digging deeper. Another key feature is the RASSOR boxer design – the drums rotate in different directions. This allows not to use large efforts of soil sampling in low gravity.
Once the drums are filled RASSOR, the robot stops collecting and moving toward the processing plant. For the discharge of regolith machine simply spins the reels in the opposite direction, the material falls through the holes in the drums, which were produced through his collection. Having the factory has its own robotic arm-lift delivered to the regolith collects and sends it to a bootable tape factory, which in turn delivers the material in a vacuum oven. There is a regolith will warm up to high temperatures. Contained in the material molecules of water will be blown dry with a circulator, and then to assemble using a cooling thermostat.
You may wonder: “did the Martian regolith was initially not dry?”. Dry, but not everywhere. It all depends on where and how deep you dig. In some areas of the planet just a few inches under the surface there are whole layers of water ice. Still below can be sulphate of lime and Sandstone, which may contain up to about 8 percent water of the total weight of the array.
After condensing the spent regolith is ejected back to the surface, where the RASSOR can pick up and get into more remote from the factory place. These “waste” actually represent a very valuable material because of it with the help of 3D printing technologies, which are currently also being developed at NASA, you can create protective structures for settlements and roads and landing sites.
The scheme of mining on Mars, in pictures:
Development: a Wheel produces fence regolith rotating buckets with holes zaboroneni
Transportation: Spinning back buckets-drums unload the regolith robotic arm in factory
Processing: To extract water from the regolith it is heated in a furnace, where the electrolysis of hydrogen and oxygen
Transmission: After receiving a certain volume of a material, the other robotic arm is equipped with a special protective closed system, downloads it to the mobile robotic tanker
Delivery: Tanker delivers water, oxygen and methane to the dwelling of people and dump them in the tanks long term storage
Use and storage: the Astronauts will use water and oxygen for breathing, and also growing plants; the fuel will be stored as cryogenic liquids for future use
All the water that will be extracted from regolith will undergo a thorough cleaning. The cleaning module will consist of a multiphase filtering system, as well as several deionizers substrates.
The fluid will be used not only for drinking. It will become a key component in the production of rocket fuel. The splitting of H2O molecules through electrolysis into hydrogen molecules (H2) and oxygen (O2), and then compression into a liquid, it will be possible to synthesize the fuel and oxidizer, which are most often used in liquid rocket engines.
The difficulty lies in the fact that liquid hydrogen must be stored at extremely low temperatures. To do this, NASA wants to turn the hydrogen in the fuel, which would be the best way to store methane (CH4). This substance can be obtained when hydrogen and carbon. Where to get carbon on Mars?
Fortunately, on the red planet it very much. The Martian atmosphere is 96 percent carbon dioxide molecules. The capture of this carbon problem is a special freezers. Speaking in simple words, it will create out of thin air the dry ice.
Having with electrolysis hydrogen and producing carbon gas from the atmosphere through chemical process — Sabatier reaction — they can be connected in methane. To do this, NASA is developing a special reactor. It will create the necessary pressure and temperature to maintain the conversion reaction of hydrogen and carbon dioxide into methane and water as by-product.
Another interesting detail of the processing plant is embolicescie the robotic arm for the transfer of liquid to the cistern mobile tanker. Is unusual about this system is that it is a specially protected from the external environment and in particular dust. Regality the dust is very fine and can penetrate almost everywhere. Since the regolith is composed of broken volcanic rock, it is very abrasive (literally clings to everything) that can create serious problems for the operation of the equipment. The lunar mission of NASA in the past has shown how dangerous this substance is. It can upset the indications of electronics, led to the jamming of mechanisms and become the cause of failures in the temperature controller. Protection of electrical and fluid transmission channels of a robotic arm, like any very sensitive electronics, is for scientists one of the priorities.
Programming umbilically robotic arms for connection to a mobile tanker. The manipulator is used for filling tankers, liquid fuel, water and oxygen
On each side ombilicale a camera mounted on the robotic arm are doors that act as air locks that protects all the internal channels of dust. To connect the camera with the mechanism of the tanker is required to follow three steps: first, after filling of the chamber is required to securely close the door from both sides to create protective dust-proof barrier. Second, in each of the doors embolicescie the camera, you need to open a small sealing apertures through which will be provided access to the channels of transmission resources installed on special moving plate. Third, you want to align the position of the transmission channels umbilically chambers and channels of reception of the material mechanism of the tanker, just connected both electric and fluidic connectors.
The robotic arm toplivoprovoda factory will embolicescie put the camera on a mobile robotic tanker, and then to unload the materials manufactured. Filling system in this case would be to look a lot like the gas station on the Earth, but at gasoline, it will pump the water. Or liquid oxygen. Or liquid methane. Or all together at once.
Recently engineers involved in the development of this project, conducted a test demonstration installation in Florida. At this stage, the scientists had to resort to simulation of the processes of electrolysis and the oven to reduce the cost and complexity of the installation. In addition, was conducted a simulation with water three products. But in this case we used the prototypes hardware and software for all parts of the installation.
Combining all the parts together, the Swamp Works engineers were able to determine the presence of various problems in design, and to determine some important details that would be impossible to determine if such tests were carried out already in the last stages of development and integration. According to the developers, rapid prototyping and early integration is a distinctive approach to the work of their team. This allows you to quickly find out the efficiency of a particular idea, and to determine all faults at an early stage.
The essence of the Martian rocket-fuel factory is that all this equipment will be Packed in a small convenient box delivered to the Red planet, and then go unpack and start fulfilling its tasks long before Mars will arrive the first people. The development of manned missions to Mars will depend on the effectiveness of this Autonomous factory. Because without it people will not be able to return back to Earth after his watch. In addition, NASA is also working team who are engaged in the cultivation of all kinds of food (including potatoes). New crop plan to grow again Autonomous method while sending people to Mars and flight back to Earth, so people are always waiting for fresh harvest.
In General, the project is really huge and requires careful preparation.
NASA has a large stock of experience of Autonomous Rovers and landing modules on Mars. For example, the latest Mars Rover “Curiosity” landed on the Red planet in 2012, the “Mars 2020”, which will go back in 2020 – possess and will possess a high level of autonomy. However, the creation, delivery and use of the Martian rocket-fuel factory in the long term and with the highest level of autonomy would require the use of such technologies that will take space engineering to a whole new level.
To test the robot excavator NASA uses a closed area, covered more than a hundred tons of fragmented volcanic rock. Minerals serve as an analogue of the smallest and abrasive the Martian dust
To start space colonization, scientists and engineers will have to solve many technical problems. For example, it is very important to determine if each subsystem develop installation for the extraction of natural Martian resources to scale. Will she be able to meet all the needs and attain a level of bandwidth that will be required in the framework of manned missions to the Red planet.
According to recent estimates by NASA, this system about 16 months will produce about 7 tons of liquid methane and about 22 tons of liquid hydrogen. On this basis, for maximum impact it is necessary to accurately determine the most suitable locations for the deployment of a factory for the collection and recycling of resources. In addition, you need to calculate how much RASSOR excavator is required to deliver to Mars, and how many hours per day they will need to work to reach the desired production plan. In the end, you need to understand how big should a freezer be for carbon, the Sabatier reactor and how much all that stuff will consume energy.
Also, scientists need to anticipate potential unforeseen problems that might interfere with the extraction and processing of resources, potentially delaying the sending of the next expedition to the Red planet. It is necessary to assess all possible risks associated with these problems and to develop correct and quick solutions to them, perhaps equipping the system with redundant elements for the temporary replacement of the failed equipment.
You need to ensure that the robotic technology will be able to support operational activities and maintenance required for several years, so their development will be in strict accordance with established standards. For example, you need to minimize the volume of used moving parts. Thus it will be possible to minimize the impact regality of dust on the efficiency of the entire system. If we approach the issue from the other side and start to design moving parts with a higher resistance to dust, then this will not only complicate the whole system, but also adds to her weight, which, as already mentioned, the value of gold.
Scientists also have to figure out how and in what proportions small and hard regolith mixed with ice under the surface of Mars. These data will help to more effectively prepare the excavator for the extraction of resources. For example, the current version of the bucket RASSOR is most adapted to collect regolith mixed with lump ice. However, this design is less effective when you need to “bite” into larger layers of solid ice. For the development of more suitable equipment is necessary to get an accurate picture of the distribution of ice on Mar. Another option is to develop a stronger, more complex, heavier and versatile equipment that can work with any kind of soil and density of the ice layers. But again, it’s a waste.
Still need to resolve issues associated with long storage sverhkrupnyh liquids. Storage technology of substances and materials under high pressure are constantly improving, but can modern technology to work on the surface of Mars for an extended period of time?
In General, in the coming years, NASA scientists will address all these issues. The Swamp Works engineers, in turn, will continue to improve the efficiency and readiness of all developed components of their system. Excavators plan to make one more strong and light. After that is scheduled to begin their trials in artificially created and as close to the Martian conditions. Scientists also want to improve the quality and efficiency of the blast furnace, electrolysis system, and to develop a scalable model of the Sabatier reactor and refrigeration installations for the production of carbon. The developers are confident that the solution to these and many other tasks that will lead to the fact that pilsbury prototype will cease to be a prototype and in the end will do real work on the surface of Mars, providing future colonists by all necessary for life resources.
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