Page 25 - 2019 Mil/Aero eBook
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The Importance of Current-Carrying Capacity, Derating, and Contact Design in Nanosatellite Applications
Alexis De Lassat, Global Product Line Leader; Adnane Jaghmim, Test & Measure Manager; and Nataliya Matveya-Mayaki, Brand & PR Manager, Nicomatic Group
Every satellite mission is critical because the ability to repair a failure post-deployment is almost always either cost prohibitive or next to impossible. Even nanosatellites, which only weigh between 1kg and 10kg, can cost many thousands of dollars to launch. So, if a satellite fails to perform purely because of a faulty connector, then that wrong connector choice will prove very expensive indeed. Of course, the components used in satellite applications have to comply with very specific and stringent specifications that define allowable electrical and mechanical performance characteristics, including size, weight, and materials, and resistance to shock, vibration, and temperature extremes. In addition, since connectors provide both electrical and physical connectivity, and component miniaturization — beyond what may be required by specifications even — is so essential to minimizing satellite payload, it is crucial to conduct a thorough analysis of connector characteristics and performance capabilities prior to design-in.
Nanosatellites like the Army’s SMDC-ONE provide critical communications capabilities for soldiers operating in remote areas where terrestrial field communications capabilities are non-existent.
One nanosatellite form factor, the CubeSat, is built using modular 1U blocks that measure 10cm x 10cm x 10cm, weigh a maximum of 1kg, are designed to carry one or two scientific instruments into space at a comparatively low cost to other, larger satellites, and can be combined into double-cube (2U), triple-cube (3U), and even six- pack (6U) configurations to extend performance capabilities. Yet, even CubeSats generally cost around $100,000 to make and $50,000 to launch, so connector failures must be avoided at all costs.
Connectors are such a critical component because they not only transmit signal and/or power throughout a system, but also physically connect various system elements. As such, satellite designers must consider both mechanical stresses and electrical performance requirements when specifying connectors in these critical systems. Space applications require connectors capable of surviving high levels of shock and vibration at launch plus the temperature extremes of space, as satellites orbit between exposure to the sun and the dark side of the moon. There are, of course, extremely rugged and exceedingly durable connector systems available, but many of these are heavy and bulky and are quite unsuitable for space missions in miniature satellites where space and weight are at an absolute premium. The ideal connector systems for these applications are small and lightweight, but both robust and durable enough to survive and deliver high performance in space environments. Commercial

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