A systems-engineering assessment of multiple CubeSat build approaches

Abstract

This research conducts a broad systems-based analysis of CubeSat engineering, with a focus on testing, failures, and their relationship to program cost, in order to assess multiple build approaches with a goal of maintaining the advantages of CubeSat missions while increasing reliability. In this work, the multiple approaches are called "beta build strategies," and we show that satellite engineering groups with minimal experience can increase their probability of success by building two flight-model versions of their satellite, allowing for more exhaustive and potentially failure-inducing testing to be conducted on the first (beta version) satellite. This differentiates itself from the standard CubeSat build approach, which is typically to build a flat sat, then an engineering model, and then a flight model of the satellite. Frequently with CubeSat development, the additional expense of building a flight-like engineering model is avoided. However, in this work we consider the probability of success and overall cost impact for multiple approaches toward the flight build. We find that by spending an additional 33% of the planned program cost, a team which plans to take this alternate approach from the beginning can build and launch two flight-model versions of their spacecraft, increasing probability of success by 30%. This cost corresponds to a 40% saving from the scenario in which the decision to build a second flight-model spacecraft is made only after the first fails. The question which this analysis tries to answer is not, "how does a group spend the least amount of money to get their first CubeSat into space?" but rather, "how does a group spend the least amount of money to get a CubeSat into space that works?"