Awards & Nominations
Space Falcons has received the following awards and nominations. Way to go!
Global Nominee
Out of This World Aeroponics - Dynamic Aeroponics System for Long-Term Space Exploration
High-Level Project Summary
Our solution to providing astronauts with vitamins and supplemental food utilizes aeroponics, adapted for space. Fresh crops would be most useful during the trip back, so we have a dynamic capsule that can expand from a storage to a production system. Ideal crops to cultivate are kale and legumes. Our design minimizes mass and volume, as aeroponics requires much less water and no soil. It’s also stackable, compact, and reduces nutrient runoff. In addition to supporting long-term missions on Mars, this design can make an impact on Earth. In rural, developing countries, farmers could use this model to produce food in areas with limited water, as well as reduce the disease spread among crops.
Link to Project "Demo"
Link to Final Project
Detailed Project Description
This modified aeroponics system uses autonomous regulation based on the different parameters that are necessary to maintain homeostasis. Our code simulates our aeroponics module and outputs the necessary adjustments. We considered the following in our design of the module:
The mass of the completed aeroponics module was an important design consideration. Since the payload capacity of rockets is limited, it is beneficial to conserve weight. The mass of this completed module was estimated to be around 14,000 to 20,000 kg (see space agency data for more information on estimation). This weight would easily be able to be lifted by the cargo version of NASA’s SLS rocket (currently in development). To reduce the space the module takes up in the rocket, the module is designed to fold. This folding only occurs in one axis to reduce complexity. This system would use a technology similar to the Bigelow module (see the Space Agency Data section for more information).
Any space module needs to be built from materials which could withstand high temperatures, pressures, and dynamic stress. The aeroponics module is no different, as it uses similar construction to the ISS modules. On the outside, there is a thin thermal blanket which is used to maintain temperatures. Next, high grade steel and titanium make up the skin of the module. This skin sandwiches different layers of kevlar, and also some water, which are both used to counter space travel threats, such as micrometeoroids and galactic cosmic radiation.
As spacecraft travel away from Earth, the protective effects of Earth’s magnetosphere and Van Allen Belts are no longer present. To combat this problem, the water reservoir was incorporated into the module wall, diminishing the harmful effects of GCRs and solar radiation. As water is recycled in space with over 95% efficiency, the storage tanks in the walls would not dry up over the course of the mission.
Running and maintaining an aeroponics module is an energy intensive task. Not only would the maintenance equipment (needed for humidity and nutrient concentration control) require power, but the module would also need to be heated and cooled, as the temperatures and sunlight exposure away from Earth can vary greatly. The Canadian Nauvarik project was able to successfully support a small community in Gjoa Haven, Nunavut (which routinely sees cold temperatures comparable to those of Mars nights) using completely renewable resources, such as wind and solar power. For our space aeroponics module, we hope to similarly capitalize on the intense solar energy of the martian daytime with solar panels.
We used SketchUp for 3D modeling of the design. Some models used in the 3D model were imported using SketchUp libraries.
We used Snap! for coding to simulate the regulation of the production system based on the different parameters and inputs of conditions and crop type. The specifics of these variables are discussed below.
The primary objective of growing crops on this long-term exploration mission is as a supplement to the crew’s diet, particularly when nutrients like vitamin C, K, and B1 are needed on the return trip. Thus, kale and peas were chosen to be cultivated, as they complement each others’ nutrient profiles, can be grown aeroponically, and can be harvested about two months after they have been planted.
Ambient CO2 concentration is maintained at 450-780 ppm to optimize plant growth; according to Gopinath et al., this ambient CO2 concentration provides optimal photosynthetic conditions for the plants. While the module is on the spacecraft, the CO2 concentration is supported by the excess CO2 produced by the crewmates. While the module is deployed on the Martian surface, the CO2 concentration can be supported by the atmospheric CO2, which is present at 95% in the martian atmosphere (a compressor must be used to pressurize the lower density environmental CO2). If CO2 levels are ever too high, CO2 scrubbers will be activated to reduce CO2 levels: while on the spacecraft, the oxygen concentration will naturally increase due to the oxygen produced by photosynthesis.
The humidity of the aeroponics module is maintained between 90-95% through the use of a water atomization nozzle that produces water droplets between 30 and 100 microns, as described by Gopinath et al.. Any smaller, and you would have a fog-like effect, and plant growth would be diminished. Any larger water particles would fall out of the air. This atomization nozzle, along with a dehumidifier apparatus, is connected to the water reservoir. The water reservoir is incorporated into the module shell, as to also shield the interior from galactic cosmic radiation.
The reservoir has several sensors that measure pH, electrical conductivity, and the concentration of essential nutrients like ammonium, ammonia, phosphorus, and potassium. While each plant may have its own unique nutrient requirements, for the sake of the simulation, the code maintains a general nutrient profile that supports most plant life. Through the use of calcium carbonate reservoirs (to increase pH) and calcium chloride reservoirs (to decrease pH) the pH of the water reservoir will be kept between 5.8-6.3, a slightly acidic solution that supports aeroponic farming methods, as described by Gopinath et al. Similarly, electrical conductivity of the reservoir solution will be kept between 1.5 and 2.5 deciSiemens per meter, as suggested by Lakhiar et al. It will be modulated by calcium ion reservoirs and a calcium chemical filter. Essential plant nutrients, like ammonium, ammonia, phosphorus, and potassium are similarly controlled by their respective reservoirs and selective chemical filters. Gopinath et al. outline target nutrient concentrations: the ammonium concentration is kept near 0.54 g/L, the ammonia concentration is kept near 0.35 g/L, the phosphorus concentration is kept near 0.40 g/L, and the potassium concentration is kept near 0.35 g/L.
3 model vegetables can be considered by the simulation: red kale, peas, and potatoes. The crew can choose which vegetables to grow on their mission. Kale was selected because of its hardiness in colder temperatures, 65% increased yield in aeroponic farming methods (when compared to traditional soil farming methods by Gopinath et al.), and high density of vitamin A, vitamin K, vitamin C, vitamin B6, manganese, calcium, copper, potassium, and magnesium. Peas were selected because of its ability to supplement kale’s nutrient profile; in addition to vitamin A and K, peas contain thiamine, folate, iron, and phosphorus. Potatoes were also considered because of their potential to impact farmers on Earth: minitubers cultivated using aeroponic technologies appear to produce more tubers, have higher tuber yield weights, and are less susceptible to pathogen transmission when compared to traditional farming techniques.
The simulation code keeps temperatures inside the aeroponics module within acceptable ranges that are specific to these 3 model vegetables:
Red Kale (Brassicae napus var. pabularia): 7–29°C (Cornell University)
Peas (Pisum sativum): 15-25°C (Sita et al.)
Potatoes (Solanum tuberosum): 10 - 20°C (yara.us)
Since the module must be shielded from radiation, no natural light can enter the module. Therefore, the aeroponics module also has an artificial light system that emits light with illuminance between 15000-20000 lux to stimulate plant growth (Gopinath et al.). This system also turns on and off to simulate daytime and nighttime. This supports the plants’ natural circadian clocks, which influences photosynthetic activity, enzymatic activity, and plant growth. Day lengths can also be modulated to emulate seasonal changes. Studies show that plants with impaired circadian clocks may have lower viability, lower photosynthetic activity, and less biomass accumulation (Srivastava et al.).
Impact on Earth:
Mini-tubers grown in aeroponics systems have been shown in studies to suffer from less contamination from pathogens, produce greater quantities of minitubers, and produce greater final potato yield weight (Gopinath et al., Dimante et al.). Therefore, farmers in rural, developing regions could utilize an adapted version of the aeroponics module we have designed to produce greater overall yields with fewer resources used.
Impact on Future Space Exploration:
Any future long-term mission must have a viable way to supplement nutrition to be feasible. The development of an efficient crop production system suitable for exploration is key to this goal. This expandable aeroponics system paves the way for more robust food production methods as we delve deeper into the expanses of space.
Space Agency Data
1. https://asc-csa.gc.ca/eng/sciences/food-production/default.asp
The Canadian Space Agency’s Naurvik project provided us with a successful attempt to support a hydroponic system in extreme conditions. We expanded upon this success, utilizing aeroponics in our design. We also plan to use similar technologies to generate electricity to support the regulation of our aeroponics module.
2. https://www.nasa.gov/exploration/systems/sls/overview.html
The SLS Block 2 vehicle will have a lift capacity of over 46,000 kg for deep-space missions, such as to Mars.
3. https://www.nasa.gov/mission_pages/station/structure/elements/us-destiny-laboratory
We based our module measurements on the Destiny module on the ISS. It has a mass of about 14,000 kg, a length of 8.5 meters, and a diameter of 4 meters.
There are several SLS payload enclosure approaches, current and conceptual, that could house a module with these requirements. For example, the 8.4m USA has a length of 10.0 meters and an internal diameter of 7.5 meters.
Using these data, our aeroponics module would fit both the payload and mass constraints.
5. https://www.nasa.gov/content/bigelow-expandable-activity-module
Our design draws inspiration from the Bigelow Expandable Activity Module (BEAM). It utilizes inflatable technology to minimize payload volume, but can be expanded when needed, with each unit having a volume of 330 cubic meters.
Hackathon Journey
This is the first time that our team, Space Falcons, has competed in Space Apps. We are four students from New Century Technology High School, a magnet school in Huntsville, Alabama, passionate about biomedicine, engineering, and computer science. Organizing a work session at the public library, we combined our unique skill sets and worked together to design a solution to the challenge “Have Seeds Will Travel”. We chose this challenge because of its necessity in ensuring the success of long-term space explorations, as well as its significant applications for crop-growing on Earth. We understand that climate change, as well as our planet’s rapid population growth will put a strain on Earth’s farmers and call into question traditional cultivation techniques. We hope that our design will not only support extraterrestrial missions, but also will help answer some of these global problems.
We were inspired by the usefulness and efficiency of novel aeroponic systems, and adapted them to suit the additional constraints present in space. A major challenge we faced was designing a production system that could be functional in both microgravity and partial gravity settings. We solved this setback by realizing that this system would best be deployed on the return trip back. As we researched and gained a more nuanced understanding of all the components of such a complex system, we updated our 3D model and code to reflect that.
It was surprising to learn how relevant extraterrestrial missions are to tackling the challenges we face here on Earth. For example, we quickly discovered that our space aeroponics module had significant implications for rural farmers in developing countries, allowing them to maximize crop yields and minimize disease spread, while simultaneously maximizing resource utilization. Ultimately, we learned how the engineering design process can be a powerful way to create change.
We’d like to thank the teachers of New Century and our principal, Ms. Roby. We have the unique opportunity at this school to take specialized strand courses in the fields of biomedical, engineering, or computer science. Our diverse skill sets and problem-solving abilities are the result of the STEM-focused nature and support of NCTHS. Go Falcons!
References
Snap! - programming interface
SketchUp - 3d modeling software & library
Stoner, R.J. and J.M. Clawson (1997-1998). A High Performance, Gravity Insensitive, Enclosed Aeroponic System for Food Production in Space. Principal Investigator, NASA SBIR NAS10-98030.
https://arc.aiaa.org/doi/10.2514/6.2011-5044
https://chesci.com/wp-content/uploads/2017/01/V6i22_30_CS072048042_Irene_838-849.pdf
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5662899/
https://www.tandfonline.com/doi/full/10.1080/17429145.2018.1472308
https://www.nasa.gov/analogs/nsrl/why-space-radiation-matters
https://science.nasa.gov/science-news/science-at-nasa/2001/ast14mar_1
https://space.nss.org/galactic-cosmic-rays-gcr-the-800-pound-gorilla/
https://www.uswatersystems.com/what-do-water-filters-remove
https://www.healthline.com/nutrition/10-proven-benefits-of-kale#TOC_TITLE_HDR_2
https://www.healthline.com/nutrition/green-peas-are-healthy#TOC_TITLE_HDR_3
http://www.gardening.cornell.edu/homegardening/scene57dc.html
https://asc-csa.gc.ca/eng/sciences/food-production/default.asp
https://space.nss.org/the-bigelow-expandable-activity-module-beam-comes-to-the-iss/
Tags
#space #seeds #aeroponics #microgravity #gcr #nutrition #climatecontrol #plants #veggies #astronauts #partialgravity #wechoosetogotoMars
Global Judging
This project has been submitted for consideration during the Judging process.