Centrifugal Force Space Farm
This is a collegiate entry for the Growing Beyond Earth Maker Contest. This design attempts to use centrifugal force to simulate gravity, and curtail the problematic behavior of water in micro gravity environments.
Outer Cylinder
The first piece of the design is the outer cylinder. This section will hold the water and nutrient solution. The inside of the cylinder is lined with a hydrophilic material. This material should encourage the water to stick to the walls of the cylinder instead of floating and forming spheres. This is an important part of the design since the simulated gravity from the centrifugal force would not be effective without steady, maintained contact with the water. We do not know the ideal material for this purpose, this requires additional research. A hole is intentionally left in the back of the cylinder to attach a motor and piping system to supply the water and nutrients. At the end, the large opening of the cylinder will be sealed with a clear cover, allowing astronauts to monitor progress while also keeping the system contained.
Inner Cylinder
The next piece is the inner cylinder. This piece provides support for the plants. This cylinder will rotate on the same axis as the outer cylinder. The current image allows for 16 plants however it can be configured for more or fewer, depending on the size of the desired plant.
LED Light
A narrow LED light tube can provide the proper spectrum of light for optimum growth while minimizing the volume of the light source.
Maximizing Space
Space is limited on the ISS, and the cylinder design doesn't maximize the available space of the 50 cm cube. Additionally, the rotation of the cylinder will require something sturdy to attach to in order to maintain stability. So, the cylinder design will be held in a 50 cm cube, allowing for storage space in each of the four corners. Some of the storage space will need to be used to hold water and nutrient supply for the farm.
Additional Comments
This system is designed for the nutrient film technique, but it can also be considered for a wick system or even simply growing in soil.