iterations, shape-setting parameters were selected to be 550°C for 2 minutes followed by water quenching,  which yielded the best form in terms of stiffness and reversibility after deformation.   Table 2. R&R and Hinge Mechanism Performance/Functional Specifications and Requirements  Specification Description Value Requirement (with margin)  R&R Pin-Puller, Pull Force 13.34 N ≥ 12.19 N  R&R Pin-Puller Stroke Length 7.1 mm ≥ 6.14 mm  R&R 2nd Stage Compression Spring, Spring Rate 0.701 N/mm 0.235 – 0.736 N/mm  R&R 2nd Stage Compression Spring, Stowed Force 6.05 N 2.03 – 6.35 N  R&R 2nd Stage Travel Distance 7.62 mm ≥ 5.87 mm  R&R Operating Power Rating 6 volt limited, 3.0 amps 6 volt limited, 3.0 amps max  R&R SMA Transition Temperature 150 to 160°C > +50°C* R&R Temperature Operation Range -51 to +61°C -40 to +50°C R&R and Hinge Maximum Random Vibe Exposure** 14.1 gRMS, 3 minutes, 3 axes 10.0 gRMS, 1 minute, 3 axes  Hinge SMA Stowed Spring Torque (1 spring) 0.190 N•m 0.140 – 0.282 N•m  Hinge SMA Transition Temperature*** -20°C > -40°C Hinge Temperature Operating Range*** -20 to +61°C -40 to +50°C Other R&R Features High temperature SMA, resettable, one mechanism releases all four SAs  Other Hinge Features Utilizes SMAs in a new application to advance the technology and SMAs  transmit power from the SAs.   * Initial R&R SMA transition temperatures were set above 100°C ** The development unit was exposed to 14.1 gRMS; the flight unit was only exposed to 10.0 gRMS *** The hinge SMA transition temperature is known to not meet the low-temperature requirement and starts to soften around - 20°C. This is handled through operational controls. When the CubeSat is in sunlight, the SMA springs will heat up beyond the transition temperature and the SAs will deploy. From an operation standpoint, the U-shaped form is rotated by an amount of ~270° while in the stowed  configuration and by ~135° while in the deployed configuration. When stowed, the material with the chosen  thickness and form is designed to exist in the end of the superelastic plateau (i.e., martensitic phase) to  provide enough force but no material damage. In the deployed state, the material partially unloads and  exists in a multiphase region to continue providing some load in order to keep the arrays open, since the  load-free state is the U shape.   In addition to the SMA springs, the hinge design consists of two lugs with bushings made out of the same  polyimide plastic with graphite as used in the R&R. The lugs and bushings rotate around a precision ground,  17-4 PH H900 stainless steel hinge pin, constrained by aluminum hinge brackets on either end of the pin. Upon deploying the arrays, a hard stop on the hinge brackets was designed to prevent the array from going  beyond the required deployment angle, since the superelastic springs continue to apply a force. Once in  the deployed state, a latch engages to act as a failsafe to keep the arrays in the deployed state should an  unknown or unexpected environment cause the springs to become too cold and temporarily lose their spring  stiffness. The design of the latch is a pin and detent type design. It converged on using a piece of spring  steel lightly preloaded on a bare aluminum cylindrical surface. When the array rotates open, the latch falls  into a slot locking the array in the deployed configuration. The latch to cylindrical surface has a thin film of  a MoS 2 lubricant applied to ensure low friction and smooth deployment.  The hinge design also transfers the electrical power from the SAs to the power management system. This  is done by conducting electricity through the superelastic springs. To ensure a good electrical path and  strong structural stiffness accommodations, the superelastic springs were riveted and directly soldered to  the SA panel and then attached to the radiator with screws. On the radiator end, the fasteners used to  attach the superelastic springs also conduct the electricity to a copper lug. Wiring harnesses were soldered  NASA/CP—2018-219887 380