Unmanned Systems Technology 012 | AutoNaut USV | Connectors | Unmanned Ground Vehicles | Cobra Aero A33i | Intel Falcon 8+ UAV | Propellers | CES Show report

40 Focus | Connectors variations are also extreme, generating stresses in the interconnect materials. The seals around the connectors are another key area, as a craft enters a vacuum. Connectors need to undergo outgassing to ensure that the seals operate effectively. Certain elastomers and plastics contain volatile organic compounds (VOCs) that will be released slowly over time. If the VOCs are released naturally while in orbit through evaporation, as they will in a connector that has not been outgassed or vacuum-degassed, the VOCs will re-condense on other surfaces and can quickly degrade equipment and jeopardise performance. Connector outgassing speeds the release of these compounds, baking the VOCs out of the connector. This can take several weeks, although new processes can allow this to happen in four hours. Physical connectors Fuel line connectors have been a particular challenge for UAVs. The small size and low weight requirements have seen a new generation of dripless quick- connect fluid coupling connector being developed in nominal flow diameters from 3.175 to 19.05 mm. Conclusion The drive for smaller systems and smaller connectors is at odds with increasing power requirements, so connector designers are developing innovative contact designs to meet that challenge. As more sensors and control systems are leading to more complex wiring harnesses, the choice of connector becomes even more critical to the performance of an unmanned system. Many connector makers have a roadmap for a 1 mm pitch in their high- reliability ranges, and are addressing the fragility and assembly issues, but the consensus is that this is probably as small as you would want to go, with a 1.27 mm system in 2018 and moving to 1 mm a few years later February/March 2017 | Unmanned Systems Technology The Microflex interconnection is a flat cable harness with screw fixing for high- vibration environments that gives a weight reduction of up to 60% over a round cable (Courtesy of Nicomatic) This dripless quick connect fuel line connector is gaining traction in UAV designs with combustion engines. The coupler operates at up to 150 psi and from -32 C to +90 C with avgas, diesel and JP8 fuel as well as compressed air and light engine oils (Courtesy of Battlefield International) New techniques for outgassing are reducing the lead time for connectors for space systems (Courtesy of PEI Genesis)