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A versatile and heretofore unutilized coupling is obtained by press-fitting a hollow nickel titanium shape memory alloy (SMA) shaft into a steel hub. This produces an SMA interference coupling that is distinct from other SMA actuators by the method in which the SMA is used. Press-fitting the hollow SMA shaft in its detwinned martensitic phase into a steel hub creates a joint capable of holding parts such as emergency doors, satellite solar panels, or tamper locks securely together until commanded release. Release is accomplished by heating the SMA to its activation temperature. The resulting decrease in diameter of the hollow SMA shaft allows it to easily slip out of the hub, releasing the part. Load testing of the SMA interference coupling showed ultimate strengths about twice that of traditional press-fit coupling strength calculations. The coupling can be designed to be a simple mechanism of very small size, on the order of one cubic centimeter, capable of achieving coupling strengths in excess of 4000 N (900 lbf).

This thesis describes the design, development, and testing of an innovative nonexplosive actuator (NEA) microcoupling device. The micro-coupling is obtained through the use of a nickel titanium (NiTi), shape memory alloy (SMA) cylindrical ring that is press-fit, in its detwinned martensitic phase, into a steel bushing, creating an interference joint. This SMA interference joint can subsequently decouple upon command, by heating the SMA cylindrical ring into its smaller austenitic memory shape, freeing it from its press-fit. The micro-coupling can be engineered to very small sizes, on the order of one cubic centimeter, and achieve coupling strengths in excess of 4,000 N (900 lbf). The SMA micro coupling's concept validation, mechanization, and development into a device for satellite incorporation are explored by assembly and experimentation. Research on pseudoelastic material properties, analytical predictions, and tests of coupling strengths are examined to characterize the SMA micro-coupling. While the micro-coupling's characteristics are desirable for many applications, its small size, simple interface, and lowpower zero-shock actuation are ideal for employment on nano-satellites to effectively increase space deployable actuation reliability by eliminating reliance on motors, clasps, latches, material fracture, or explosive devices., http://archive.org/details/developmentofnan109455015, US Navy (USN) author, Approved for public release; distribution is unlimited.

This thesis describes the design, development, and testing of an innovative nonexplosive actuator (NEA) microcoupling device. The micro-coupling is obtained through the use of a nickel titanium (NiTi), shape memory alloy (SMA) cylindrical ring that is press-fit, in its detwinned martensitic phase, into a steel bushing, creating an interference joint. This SMA interference joint can subsequently decouple upon command, by heating the SMA cylindrical ring into its smaller austenitic memory shape, freeing it from its press-fit. The micro-coupling can be engineered to very small sizes, on the order of one cubic centimeter, and achieve coupling strengths in excess of 4,000 N (900 lbf). The SMA micro-coupling's concept validation, mechanization, and development into a device for satellite incorporation are explored by assembly and experimentation. Research on pseudoelastic material properties, analytical predictions, and tests of coupling strengths are examined to characterize the SMA micro-coupling. While the micro-coupling's characteristics are desirable for many applications, its small size, simple interface, and lowpower zero-shock actuation are ideal for employment on nano-satellites to effectively increase space deployable actuation reliability by eliminating reliance on motors, clasps, latches, material fracture, or explosive devices.

This thesis describes the design, development, and testing of an innovative nonexplosive actuator (NEA) microcoupling device. The micro-coupling is obtained through the use of a nickel titanium (NiTi), shape memory alloy (SMA) cylindrical ring that is press-fit, in its detwinned martensitic phase, into a steel bushing, creating an interference joint. This SMA interference joint can subsequently decouple upon command, by heating the SMA cylindrical ring into its smaller austenitic memory shape, freeing it from its press-fit. The micro-coupling can be engineered to very small sizes, on the order of one cubic centimeter, and achieve coupling strengths in excess of 4,000 N (900 lbf). The SMA micro coupling's concept validation, mechanization, and development into a device for satellite incorporation are explored by assembly and experimentation. Research on pseudoelastic material properties, analytical predictions, and tests of coupling strengths are examined to characterize the SMA micro-coupling. While the micro-coupling's characteristics are desirable for many applications, its small size, simple interface, and lowpower zero-shock actuation are ideal for employment on nano-satellites to effectively increase space deployable actuation reliability by eliminating reliance on motors, clasps, latches, material fracture, or explosive devices.