NanoRacks-Girl Scouts of Hawai`i-Microgreen Plant Growth (NanoRacks-GSH-Microgreen Plant Growth) - 07.29.14
ISS Science for Everyone
Science Objectives for Everyone
NanoRacks-Girl Scouts of Hawai`i-Microgreen Plant Growth (NanoRacks-GSH-Microgreen Plant Growth) tests the changes in growth of arugula in microgravity. This experiment was chosen to collect data on the viability of edible plants grown in microgravity.
Science Results for Everyone
OpNom NanoRacks Module-22
NanoRacks, LLC, Houston, TX, United States
Sponsoring Space Agency
National Aeronautics and Space Administration (NASA)
National Laboratory Education (NLE)
ISS Expedition Duration
September 2012 - September 2013
Previous ISS Missions
- NanoRacks-Girl Scouts of Hawai`i-Microgreen Plant Growth (NanoRacks-GSH-Microgreen Plant Growth) researches growing edible plants to support further space exploration by maintaining an available supply of fresh produce for said explorers.
- NanoRacks-GSH-Microgreen Plant Growth grows arugula in a hydroponic system with 8 seeds, and c in a natural medium, and watered with .5 mL of tap water daily. Collect data on the plants’ germination and viability for harvest after only 11-15 days in a microgravity environment
- NanoRacks-GSH-Microgreen Plant Growth provides 8 high school Girl Scouts from O`ahu, HI, a once in a lifetime learning and living experience through our Quest Institute partnership.
- NanoRacks-GSH-Microgreen Plant Growth impacts the other 4,900 Girl Scouts of Hawaii, by showcasing the 8 team members and entire ISS project through our communications department.
- NanoRacks-GSH-Microgreen Plant Growth impacts crewmember health directly through maintaining an available supply of fresh produce on lengthy missions in space.
Selecting a payload idea was the first and longest step of the entire investigation process. To help decide on a payload topic the group was divided into small groups to write down different ideas. Topics ranged from garbage disposal through using composting worms to growing plants hydroponically. The topic was narrowed down to hydroponics or aquaponics, then finally hydroponics was chosen. Hydroponics was chosen while considering NASA Safety requirements, the topics ability to increase scientific knowledge and also usefulness to those who must be stationed in space for long periods of time.
Next plants were researched according to the conditions the payload would endure during transit, launch, time on the International Space Station (ISS), and even transit back to earth. The goal was to grow a plant that not only increased oxygen levels but also provided food to the astronauts. Another key element considered, as the specific plant for the payload was researched, was the limited growing space within the MicroLab. It took a few weeks, but the decision was eventually made to use “microgreens” for the investigation plant to grow hydroponically. Microgreens are herbs harvested 10-15 day after sprouting, small in size and germinate quickly. Not only would astronauts be able to eat these delectable greens, but they have medicinal purposes as well. Of the seeds tested, the team voted to use micro arugula.
After choosing micro arugula the team started designing an incubator to hold the hydroponic system. The team decided on a cylindrical plastic tube that would hold the medium, (Sunleaves, super starter plug, all-natural 95 percent composted tree bark with a natural polymer) and 8 arugula seeds (Nalo Farms). Then the team determined how the plant incubator would be held in place in the MicroLab. Different ideas were sketched of an incubator holder. Then using a three dimensional modeling computer program, a bracket to hold the incubator was designed and then with access to using a 3D printer at Oceanit Laboratory we printed the incubator bracket to use for the payload mechanical design. The bracket design included a base surface that would allow the entire bracket to slide into place at the bottom of the MicroLab. On top of the flat plane of the base piece, two “U”-shaped components that the incubator would sit on were designed. In between the holders there was a short rectangular piece that connected the holders together; this piece had a hole on each side that would allow the incubator to be tied to the bracket. After running some tests, the bracket for the cylindrical incubator lying along the width of the MicroLab with the plants growing outside of the incubator towards the camera was changed instead to the cylindrical incubator lying along the length of the MicroLab with the plants growing entirely inside of the incubator. The medium, seeds and the plants would be in the tube, and the plants would grow inside the tube towards the camera. The redesigned bracket had three “U” shaped holders going along the length of the flat plane. This bracket also had a wall that separated the water bag from the incubator. After some minor modifications, the final bracket was printed. The holders on the new bracket were shorter, so they wouldn’t conflict with the parts hanging off the circuit board. There was also an added section on the wall that divided the water bag (plastic 50 mL IV bag) filled with 25 mL of water and incubator that had two holes to allow tubes to travel to and from the water bag to the incubator.
The team started to plan and design the computer programming to facilitate the payload operating remotely while on the ISS. Not knowing anything about programming, the team started out with the introduction through BASIC programming. The team learned the fundamentals of writing code. In order to write the LED light code, it had to be determined which lights were most optimal for the arugula microgreens. A purple light frequency made up of red and blue was chosen. Another large part of the programming process was when and how long to water the seeds and then the plants. Based on a 30 day schedule of the energy distribution and the water flow, how and when to integrate programming codes had to be integrated to facilitate the payload operating remotely while on the ISS. Watering at midnight everyday was chosen based on the energy limits available to us. The entire schedule and flow chart was established before any coding was completed. Once the programming was started, it had to be recoded with the BIOS according to the master code. After sending it to San Jose got notes from Basic Input/Output System (BIOS) expert Mr. Howell Ivy were received and finalized the programming errors. He also assisted in the PuTTY software that enables photos to be taken in the MicroLab and the overall code. The big moment came for the programmers as well as the whole team when the MicroLab was plugged into the Nanolab, after what seemed like the millionth try, the green status bar filled up to the end on the computer and the lights came on at the exact time making our programming code a success!
Next,the electrical elements were designed after the programmer and design and concepts plans were drafted. The electrical interface board was designed with a computer software program called PCB Express. The electrical interface board was then designed on the computer so that the complete version from PCB Express could be ordered and printed. Two computer programs were used: PCB Schematic and PCB Express. The first program used was PCB Schematic where the correct components were found and input onto the board. The team had to make sure that the components were not going to interfere with the payload’s bracket, plant incubator or water bag, which takes up a majority of the space in the MicroLab. Therefore, the colored LEDs and water valve were moved next to the camera in an area where they wouldn’t interfere with the pictures. The red LED 1 (3mm, 5V 35mcd) was placed at A 7 and 8 (pin 7, 16 ground), red LED 2 (3mm, 5V 35mcd) at A 10 and 11 (pin 9, 14 ground), blue LED (5mm, 5V, 300mcd) at B 8 and 9 (pin 8, 15 ground), white LED N&L (3.5V, 600 m/m) at 6 and 4 (pin 11, 18 ground) and the Face Mount Solenoid Valve (Lee Company, 5V DC, ported version) at 1 and 2 (pin 10, 17 ground). Once this drawing was finished, it was sent up with Ms. Bella to San Jose for a flight test, where they checked the design and suggested three new parts be added: a capacitor (DigiKey, 100mF, 5V), a semiconductor (DigiKey, voltage reverse 20V,) a microchip as the voltage driver (DigiKey, 20 pins) and finally a connector from the payload interface board to the MicroLab (DigiKey, 26 pins). The design was revised and then transferred to the PCB Express program where traces were added to connect the components to the electrical output. The board was sent out, built and delivered back to the team and then soldered on the different payload specific parts.
The final step of the project was to put together all the components of the payload, slide them all into the MicroLab and load all the flight ready computer programming codes.
NanoRacks-GSH-Microgreen Plant Growth shows how a simple plant and harvest system creates a readily available supply of fresh produce for consumption on lengthy missions or emergency situations in space.
NanoRacks-GSH-Microgreen Plant Growth shows how, in a community with little to no agricultural land and sunlight, edible plants can be grown in a very small spaces and also be constantly viable and sustainable through artificial means at very low cost as well.
NanoRacks Module-22 is completely autonomous and only requires installation and removal. NanoRacks Module–22 returns on 33S.
Crew interaction with Module-22 is limited to transferring the NanoRacks locker Insert from the launch vehicle to the ISS, installation and activation of the NanoRacks Frames into the EXPRESS Rack Locker, cleaning of the air inlet filter (as necessary), and data retrieval (as needed) during the mission.
VCS ISS Project
An electrical interface board for NanoRacks-Girl Scouts of Hawai`i-Microgreen Plant Growth (NanoRacks-GSH-Microgreen Plant Growth), mounted with four LED lights and a valve on the lower portion of the image is shown. The bag on the right side is the water bag wrapped in standard rubber bands to create pressure that forces water to leave the bag and enter the plant incubator. The prototype plant incubator is at the center of the image made of plastic with openings that are covered over with water resistant fabric to allow air flow. The incubator is held into place on the prototype plastic bracket made on a 3D printer. Image courtesy of Girl Scouts of Hawai`i.
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A close up of the plant incubator in the NanoRacks-Girl Scouts of Hawai`i-Microgreen Plant Growth (NanoRacks-GSH-Microgreen Plant Growth) investigation. The light green material surrounding the planting medium is florist sponge. The planting medium is all natural bark and other plant fibers. Image courtesy of Girl Scouts of Hawai`i.
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This test bracket design included a base surface that would allow the entire bracket to slide into place at the bottom of the MicroLab. On top of the flat plane of the base piece, two “U”-shaped components that the incubator would sit on were designed. The watering tube is the able to be feed through the back wall of the bracket where then it is placed inside the growing medium help in the plastic incubator. Image courtesy of Girl Scouts of Hawai`i.
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The flight components as seen outside of the MicroLab NanoRacks-Girl Scouts of Hawai`i-Microgreen Plant Growth (NanoRacks-GSH-Microgreen Plant Growth. The flight electrical interface board is mounted with four LED lights, three with two long leads, one with four short leads and the valve on the left side of the image with three ports to transport the water to the plant incubator. The bag on the right side of the image is the flight water bag wrapped in standard rubber bands to create pressure that forces water to leave the bag, pass through rubber tubing to the valve, then to incubator. The flight incubator plastic black bracket securely holds the plant incubator. Image courtesy of Girl Scouts of Hawai`i.
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