Structural assesment of joints in satellites using guided waves

The intention of the Air Force’s Responsive Space Initiative Project is to develop procedures and technologies necessary to produce a satellite within six days from the initial order. Modular satellite designs have been proposed to help streamline the process of preparing a satellite for deployment. These designs would save time by allowing panels with common functions to be manufactured and tested long before a new satellite is needed. Prior to launch, the integrity of the panel-to-panel connections would need to be tested for quality in order to show that the craft is flight worthy. The experimental test method presented in this thesis performs a targeted quality assessment of the connections between satellite panels. The test method is intended for responsive satellites designed with prefabricated and pretested panels for which traditional vibration testing would be redundant. A first investigation of the feasibility of using transmitted wave energy for joint quality assessment was conducted at the University of New Mexico using a simple bolted connection between two aluminum plates. Comparisons were made between wave energy transmission and a mechanical assessment of the joint rigidity. Results show a correlation between joint rigidity and energy transmission, demonstrating the feasibility of the using wave energy transmission amplitudes to inspect aluminum-to-aluminum dry connected joints. Later experiments were conducted at Air Force Research Laboratory facilities on a fully functional satellite and detached satellite panels. These experiments showed that the test method is able to detect faulty connections with higher fidelity than current satellite testing methods. The experimental setup and methods for each set of experiments is presented along with an overall assessment of the utility of the test method for use with responsive satellites.Air Force Research Laboratory Space Vehicles Directorate National Science Foundation Alliance for Minority Participation Bridge to the Doctorate Fellowship ProgramCivil EngineeringMastersUniversity of New Mexico. Dept. of Civil EngineeringMaji, ArupMaji, ArupDumm, Hans-PeterGerstle, Walte