Improving CubeSat reliability: Subsystem redundancy or improved testing?

Improving CubeSat reliability: Subsystem redundancy or improved testing?

Bouwmeester, J. (TU Delft Space Systems Egineering)
Menicucci, A. (TU Delft Space Systems Egineering)
Gill, E.K.A. (TU Delft Space Systems Egineering)

2022

The objective of this paper is to investigate which approach would lead to more reliable CubeSats: full subsystem redundancy or improved testing. Based on data from surveys, the reliability of satellites and subsystems is estimated using a Kaplan–Meier estimator. Subsequently, a variety of reliability models is defined and their maximum likelihood estimates are compared. A product of a Lognormal distribution addressing immaturity failure and a Gompertz distribution addressing wear-out is found to best represent CubeSat reliability. Bayesian inference is used to find realistic wear-out parameters by using failure data of small satellites. Subsystem reliability estimates are subsequently found using a similar approach. A reliability model for CubeSats with redundant subsystems is established, verified and applied in a Monte Carlo simulation. The results are compared with a model for reduced immaturity failure. Allocating resources to reduction of immaturity failures through improved testing is considered to be superior to allocating these resources to the implementation of subsystem redundancy.

CubeSat reliability
Subsystem redundancy
Bayesian inference
Reliability models

http://resolver.tudelft.nl/uuid:0359d0c0-0d1d-4f9a-9f1d-9be28f4fbcd7

https://doi.org/10.1016/j.ress.2021.108288

0951-8320

Reliability Engineering & System Safety, 220

Institutional Repository

journal article

© 2022 J. Bouwmeester, A. Menicucci, E.K.A. Gill