Unmanned Systems Technology 021 | Robot Aviation FX450 l Imaging Sensors focus l UAVs Insight l Liquid-Piston X-Mini l Riptide l Eurosatory 2018 show report l Zipline l Electric Motors focus l ASTS show report

31 FX450 almost a year ago, because the connectors have very long lead times. For the first few aircraft, he says, he ordered the biggest connectors that would fit in the various positions available in the airframe, just to maximise the available options with a view to using smaller ones in later aircraft when the configuration is frozen. The connectors are already filling up, he says, so the large ones may stay. He adds that the 450’s wiring system will be like that of a computer, in that just about anything can be connected to it. “You could change the engine and use the same connector because an engine needs communication to the autopilot, the emergency remote control and things like that, and that will be the same for every type of engine,” he says. It also needs to be connected to other devices including the battery and fuel pump, but all that can be accommodated in one connector. “Then if we get another engine we can order another mating connector and just wire it up. The main harness will have what it needs according to the pins I use.” Berget is to build the production harnesses for the FX450 to ISO process and IPC quality standards. They are the same as those used for the F35 Lightning II fighter, so Robot Aviation is prepared for any certification requirements it may have to meet in future. The UAV’s wiring will meet the IPC class 3 specifications that govern aerospace and medical equipment. They stipulate, for example, that when the insulation is stripped from a wire in preparation for securing it into a connector, no strand of the wire must be broken or even scraped. It also insists on full traceability for the tools used to crimp the pins to hold the wires into the connector. Every time the tool is adjusted it must be used to make a crimp connection, which must then be put through a destructive test until something – usually the wire – breaks; it must not be the crimp that breaks or even loosens. Payload accommodation and integration There are two payload bays in the FX450, one in the modular and removable nose section and the other in the mid-fuselage position ahead of the fuel tanks, which is accessed from underneath. Both are fitted with standard aircraft fasteners and hard points, and aircraft-grade electrical and data connectors. The nose bay will house a steerable EO/IR turret, on which the company is working with Trillium Engineering, FLIR Systems and DST Control. Initially, the fuselage bay will contain a multi-axis stabilised high-resolution camera, with Lidar and comms relay capabilities planned as future options to accommodate customers’ mission- specific requirements. While line-of sight data links for payload control will be customer-selected options, BVLOS comms will be handled by Cobham Aviator SP satcom hardware, with compression software from Norwegian company Ansur Technologies. Antennas for all these systems are internal and external surface-mount devices. Integration into the FX450 will be a first for the radio comms relay from Telenor. It was originally designed and packaged to spend its life 20 m up a radio mast in all weathers, so it might be very challenging from the point of view of electronics packaging and electromagnetic interference and compatibility to do that. Integration engineer Ravi Damodaran is in charge of designing the FX450’s avionics system and integrating the payloads. A big part of the job is helping customers to select the payloads and then persuading systems from different vendors to talk with each other and the aircraft. EO/IR sensor manufacturers use different, proprietary protocols to communicate with platform systems, he says, adding that even if the physical connections for payloads from different manufacturers are the same, they won’t speak the same language. The UAV industry has not yet achieved standardisation in this area. Until that happens, there are two basic approaches to making them talk, Damodaran says. The first involves going into each system’s computer and writing an abstraction layer that other Unmanned Systems Technology | August/September 2018 Robot Aviation FX450 | Dossier The fixed-pitch CFRP propeller is driven here by a modified Hirth F33 single cylinder two-stroke engine, which will be compared in a fly-off with a Zanzottera 305Hs twin (Photo by the author)