Unmanned Systems Technology 024 | Wingcopter 178 l 5G focus l UUVs insight l CES report l Stromkind KAT l Intelligent Energy fuel cell l Earthsense TerraSentia l Connectors focus l Advanced Engineering report

26 aircraft design,” Hesselbarth says. “We expanded the internal volume available to energy storage.” This, he says, adds considerable flexibility to trade off payload and range. “For mapping missions, you can use two batteries in the front and have the cameras integrated internally in the rear payload compartment of the UAV. You can also use four batteries in the fuselage and add payloads below the drone.” The 178 HL’s high landing gear allows for bulky payloads to be mounted directly beneath the aircraft’s centre of gravity using Wingcopter’s standard payload adapter, which also allows payloads to be changed between missions in a plug- and-play manner. Propulsion Motors used in any tiltrotor application have to be powerful enough for VTOL and safe hovering, and be efficient in forward flight, Hesselbarth says. The motors and electronic speed controllers used in the Wingcopter UAVs are customised units supplied by KDE Direct and others. “With our design we ensure that the Wingcopter can hover until the battery runs out without overheating,” says Hesselbarth. Motors sized for VTOL and hovering are generally over-powered for wing-borne flight, so once the UAV is established in cruise mode, the rear motors are stopped and the prop-rotors fold back to reduce drag. The motors are made using aluminium alloys that are CNC-machined and anodised to prevent corrosion. They contain custom-designed neodymium iron boron magnets with a maximum Curie temperature of 80-100 C, along with wire windings in the stators rated to 180 C, to withstand the high temperatures associated with high-performance applications. They also feature a machined aluminium front housing with multi- angled cooling holes that pump air through the motor while it runs, shielded ball bearings to support the motor shaft, and stator plates that are epoxy-coated on the inner surface to prevent winding shorts. The wire is machine-wound onto the stators for consistency, and high- temperature adhesives are used to secure the windings and prevent them from shifting, getting pinched or shorting February/March 2019 | Unmanned Systems Technology Dossier | Wingcopter 178 UAV Once established in fixed-wing mode, Wingcopters stop their rear motors and fold the propellers back to minimise power consumption and drag (Courtesy of Wingcopter) Servos are linked to control surfaces by pivoting rods. Behind this maintenance hatch is the servo that operates the right side rudder (Courtesy of Wingcopter)