Butterfly Parabola Collapsible Mirror
NASA contract work that consisted of designing, building, and testing a collapsible parabolic mirror to aid in materials access on the moon for building habitats. This project has been selected to proceed into further design steps to ultimately culminate in a product to send to the moon.
Challenge
This project was based around solving the NASA-assigned problem of habitat construction on the moon. Because the moon lacks the protective magnetic field that the earth has, NASA is seeking to combat the detrimental effects of radiation exposure on the moon by constructing habitats lined with bricks consisting of lunar regolith and polyethylene. NASA assigned the task of designing and testing a method of harnessing solar energy to melt polyethylene for the production of the lunar regolith bricks. NASA stated that the final design was required to be compact, lightweight, and provide enough power to produce 100 1” by 1” by 5” bricks per 24 hours of lunar sunlight.
Team Patch
Action
After extensive research, the project team settled on a collapsible parabolic mirror design to address the problem statement. The final iteration of the design drove both the expansion of the mirror and sun tracking through a pair of central motors mounted on the heating pipe. Upon arriving on the moon, the mirror will unfold using a set of mirror panels. The panels are designed to snap into place to create a parabolic shape which will redirect the sun’s approximately parallel radiation energy onto a single heating pipe.
Final CAD Design
Heating Testing
Expansion and Sun-Tracking Testing
Results
The final prototype could collapse in a rectangular volume that was 1/2.52 the size of the expanded prototype, an improvement of 1.25 times the NASA-set quota. The effectiveness of the mirror was tested by running water through the heating pipe and measuring the temperature difference compared with the flow rate and specific heat capacity of water. Testing indicated that the 30 cm by 30 cm prototype mirror could harness 125.7 W of solar power on the earth’s surface. Included in the presentation of the final project was a model coded in Java to estimate the power output and mass of a 50 cm by 50 cm mirror constructed with aluminum and dielectric coating. The program used the materials selected and shape and size of the final mirror along with efficiency estimations to demonstrate that the final mirror could realistically achieve a mass of 6.34 kg and a power output of 273.3 W, up to 16x the NASA power quota.