SNC Qwksep - A simple, reliable, stiff and low-shock separation system for small sat missions

The SNC Qwksep technology is a Marman band retention system with a low shock release mechanism. The Qwksep is unique in that it combines flight heritage geometry and a Clamp Band Opening Device (CBOD), packages these features in a very small height envelope of 2 inches, and provides bolt circle interfaces for the launch vehicle and payload. The system developed targeted a specific set of requirements related to small satellites in the 600 to 1,100 pound size to demonstrate the technology as opposed to a specific product. An engineering unit was designed and built to demonstrate functionality and load capacity. Finite element analysis (FEA) was used in the design stage to predict stiffness and service load capability. The engineering unit was tested for function, stiffness, and load capacity. Test results were compared to analysis predictions and show very good correlation. The engineering unit was tested to an equivalent tensile load (P_eq) of 25,000 pounds. This load envelopes the target payload launch environment. Stiffness was measured at over 3.7 × 10⁶ pounds per inch in axial tension. Correlated analysis predicts a tensile load capacity of 33,600 pounds for a 5,000-pound nominal band tension. The engineering unit tests successfully demonstrated that the technology is a viable alternative to other systems and is ready to satisfy mission requirements in the small satellite market. Sierra Nevada Corporation (SNC) Space Systems plans to have a new 15-inch diameter version qualified by the end of 2013.