Numerical Investigation of the Launch Vibration and Orbital Thermal Behaviour of a CubeSat

Thumbnail Image

Files

pac_vlad_mesc_2025_thesis.pdf (32.98 MB)

Date

2025-12-17

Authors

Abstract

CubeSat missions are subjected to the induced vibrations of the rocket during launch, and then they are exposed to an extreme thermal environment while in orbit around Earth. These conditions have the potential to damage the components of the satellite and cause a failure for the mission. Thus, numerical models are used to identify and resolve structural and thermal problems in a CubeSat design to increase the chance of mission success. The accuracy of a model is dependent on the correct application of boundary conditions and simulation parameters, as well as its level of geometric detail. A vibration and a thermal numerical model of the Western Skylark CubeSat were therefore developed with a high level of detail to accurately simulate its response to the expected environmental conditions. It was found that the increase in the resolution of the model better captured the behaviour of the Western Skylark in reaction to its environmental conditions, indicating that similar techniques should be employed by future CubeSat projects. The results showed that there were high stress concentrations in the threaded rods of the structure due to the random vibration loading. Further, two of its sensors, the Fine Sun Sensor and the CubeMag Deployable, achieved temperatures that were either below their operational or survival limits. Solutions to these concerns are provided.

Summary for Lay Audience

A CubeSat is a small satellite that can be feasibly developed by post-secondary institutions. They are relatively inexpensive to build and have a facilitated integration and deployment process for standard launch vehicles. Their objectives range from performing scientific re- search for a broad range of different disciplines, to providing commercial services for cus- tomers. However, there is a risk of failure for CubeSats that can be attributed to their launch environment, in addition to their orbital thermal environment. As a part of the satellite design process, these conditions are simulated using commercial software tools to identify potential areas of concern. During the launch phase of a CubeSat mission, the rocket engines generate vibrations that travel to the payloads. It is therefore important to simulate the response of the CubeSat to these vibration loads as they are transmitted through the shared mechanical interface with the rocket. First, the natural frequency of the CubeSat must exceed that of the rocket structure to avoid resonance. Next, the stress experienced by any of the CubeSat structures should not exceed their yield stress values with an added margin of safety. After deployment into orbit, a CubeSat will cycle through hot and cold temperature extremes. It will heat up when it is exposed to sunlight, and it will cool down when it is shadowed by Earth. The CubeSat components need to remain within their operating temperature limits to function, and within their survival temperature limits to avoid failure. Both these environments were simulated for the Western Skylark CubeSat, designed by Western University, to determine if any of its components were at risk for damage. A detailed vibration model was used to find the natural frequency of the CubeSat structure and the stress it experiences during launch, where the results revealed concerning stress concentrations on the threaded rods. Another detailed thermal model was developed to obtain the temperature distribution of the structure in orbit, where results showed that two of its sensors drop below either their operating or survival temperature limits.

Description

Keywords

CubeSat, satellite, satellite analysis, satellite vibration simulation, satellite thermal simulation, finite element method

URI

https://hdl.handle.net/20.500.14721/39319

DOI

License

Collections

Theses