Development, Integration, and Testing of a Nano-Satellite Coupling Mechanism Using Shape Memory Alloy for an Interference Joint
NAVAL POSTGRADUATE SCHOOL MONTEREY CA
Pagination or Media Count:
This thesis contains the results of a complete redesign effort, including development, integration, and experimental testing of a very small mechanical coupling mechanism. This mechanism is suitable for nano-satellites and uses a shape memory alloy SMA ring, press-fit into a metallic bushing to create a releasable interference joint. A detailed explanation of the techniques used to press-fit the SMA ring into the metallic bushing is included along with a description of why the SMA ring shrinks to its austenite phase upon heat activation and how it decouples from the metallic bushing. The coupling-engineered to be as small as one tenth of a cubic centimeter-is capable of achieving holding strengths in excess of 135 N 30 lbf. SMA characteristics and current release mechanisms are explained and tests are conducted to validate the holding strength achieved by the interference joint between the SMA and the metallic bushing. The design and part selection for each component of the Engineering Design Unit EDU is documented and launch conditions simulated to test the EDUs performance, releasability, and to validate the static holding force. Finally, this thesis describes the simulated integration of the EDU into a 3U CubeSat structure.
- Properties of Metals and Alloys