Entry Twelve - Computer-Aided Design

After my foray into 3D printing, I finally felt ready to get started on my CubeSat design. This CubeSat project is also my Project Lead the Way Capstone proposal at my high school, so I get to discuss my ideas and next steps with my teachers on a regular basis. My CubeSat is intended to test the effects of in-space radiation on commercial solid state memory devices (SSDs). While radiation- hardened memory units are available, they are very expensive and much heavier than commercial SSDs. Because of this most small satellite builders use commercial memory. However, these commercial units are vulnerable to the effects of the increased radiation environment in space. Radiation can cause errors in stored memory and can corrupt critical information, leading to mission failure.

The CubeSat that I am building is designed to expose memory units to radiation in Low Earth orbit (LEO), monitor the level of radiation exposure, and then periodically test the memory units for errors. The satellite reports any memory errors and the cumulative level of radiation exposure to ground stations on Earth. By tracking failures and exposure over time, the failure rate can be correlated to exposure. 

Before I could 3D my CubeSat, I had to design it using CAD software. I chose Fusion360 as my platform since I had familiarity with it from other projects.  The CAD model that I developed in the picture below shows the parts of the satellite.

·      On each side there are solar cells to generate power.

·      At the bottom is a uni-directional UHF patch antenna.

·      Above that is the transceiver module, which communicates with Earth.

·      Next is the power control module, which takes power from the solar panels, stores it in batteries and distributes it as necessary.

·      Then there is the on board computer which controls the satellites, conducts the experiments, collects data, and communicates when queried.

·      Finally there is the experiment module with the 10 SSDs and the radiation detector.

One can see that the design takes advantage of a modular architecture with a standard structural system and a stacked central bus that transfers all data and power – this really reduces the required wiring – it gets rid of the “spaghetti monster”.

CubeSat Prototype - Created with Fusion360