The Convergent Kale Chamber is my entry to the Growing Beyond Earth Maker Contest in the high school category. The chamber can grow any type of plant that can be harvested at a little less than 10 inches of growth and can be planted in an area with not much more than 81 square inches. A thermal regulator creates a microclimate that allows for plant germination and growth, and a refillable self watering bag pumps water into the soil underneath the plants to keep them hydrated.

I chose kale as my preferred plant because it is quick to germinate with times of as little as 8 to 10 days and can be re harvested without planting new seeds allowing for much more frequent harvesting and therefore more food (or at least the same amount of food at a faster production rate). This chamber can grow outredgeous red romaine lettuce just as well, growing 4 to 6 at a time (2-3 on each side of the planter). Unfortunately, this lettuce must be re planted in order to grow again successfully, unlike kale.

I imagined this chamber to be hung in the upper corners of ceilings of the space station to conserve space and to allow for easy access to all manipulative parts of this chamber such as the thermal regulator or the access door.

In the next steps I will go into more detail about each part of the chamber and walk through how it works.

Supplies

I used Autodesk Fusion 360 to design this, but any type of 3D modeler will work. The only two external parts that are needed for this chamber is a thermal regulator found on AliExpress for $15 and two water pumps found on Adafruit for $25 each.

Step 1: The Soil Watering System

The Soil watering system is comprised of ten 15mm tubes with small holes punctured regularly to allow for watering of the soil that surrounds them. A thin film of wax paper may need to be placed on the open side to ensure that no water or soil falls out in microgravity. The box that holds the soil is 480mm by 470mm, roughly a 20 inch by 20 inch square, perfect for growing 2-3 heads of red romaine or kale plants per side. With two soil boxes per chamber, 4 to 6 plants can be grown at once.

Water is fed to the tubes from a bag placed in between them. Two pumps pump water from the bag into the watering tubes.

Step 2: The Container and the Regulator

The container houses the thermal regulator in its bottom and the internals slide in from the side. The thermal regulator can be set to keep the inside of the container at a desired temperature, about 60 to 65 degrees Fahrenheit for growing many edible plants. The regulator can easily be accessed or managed from the bottom of the container.

The thermal regulator regulates the temperature inside of the container. The temperature can be set from the bottom of the container and creates a microclimate inside of the container that keeps the plants healthy and growing quickly.

Together, these two parts create a perfect living environment that can be tailored to any plant grown inside.

Step 3: The Inside of the Chamber

The plants grow on the inside of the chamber in this M-shaped growth area. Two soil watering systems and an LED light source are housed in a cubic design that allows for the growth of plants horizontally from the outside in. This innovative way of growing plants maximizes the amount of plants grown and allows anyone to quickly see how much the plant s have grown without doing anything but looking. Two water pumps and a water bag are also housed here to supply the plants with water. The LED block can be held once the container is open and the whole inside assembly can be taken out of the container and the plants can be harvested, planted, and inserted back into the container to be grown again.

The self watering system is a fully functional self-watering system designed for microgravity. The system is comprised of a bag filled with water, enough to water 8 plants for one week. Connected to the bag are two pumps that pump water from the bag into the self watering system previously addressed. This fully automated watering allows for the plants to grow without human interaction. The system is small enough to fit inside the container and still allow the plants to grow to their full height.

Step 4: Improvement and Conclusion

This design meets all the requirements of plant growth and requires very little human interaction. The water bag can be refilled and hold enough water for ant plants for at least a week, holding over 6,525 cubic inches of water. Perfect plant germination can be achieved with enough water, enough light, and the right temperature, all of which are supplied in my 50cm x 50cm x 50cm cube.

Some improvement to this design could be made, such as connecting the bag to a steady supply of water, allowing someone to refill the bag by opening a valve instead of refilling the bag and replacing it. Another minor improvement that could be made is a way to unfold the inside of the chamber and allow for easier harvesting.

Other than these minor improvements, my plant growth chamber exceeds the requirements of life and is perfect for growing plants anywhere, including outer space.