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49 It has also been designed with a number of redundancies, featuring primaries and secondaries for the flight controller, GNSS, antennas and almost all the other onboard electronics, to ensure a safe landing in the event of a critical system being disconnected or damaged in mid-flight. Motion Robotics, based in Southampton, England, attended the show to debut its circumferential flux electric motors. “While most people in the UAV market are familiar with axial and radial flux configurations, circumferential flux motors work by running doughnut-shaped permanent magnets inside a circle of crescent-shaped coils,” explained Dr Dennis Majoe. “That means the torque derived from the flux is directed more in line with how the motor is spinning, which means improved energy and thermal efficiency compared with the other flux designs.” While this design approach is not entirely new, circumferential flux motors remain relatively rare owing to the many difficulties involved in manufacturing them. For example, the coils are challenging to wind while still achieving a high copper fill factor (the quantity of copper wire packed into a given area). To overcome that, Motion Robotics additively manufactures many of its motor components, which eases the subsequent task of hand-winding the stator coils. The motors are then assembled manually. “We anticipate that this motor configuration will run much cooler than most others on the market, and to work especially well in high-torque applications such as heavy-lift UAVs flying with large propellers,” Majoe added. “Our base model is a 10-pole motor that runs cool at about 3.5 kW, with a typical 48 V supply and 40-50 A of current, delivering between 20 and 25 kg of thrust at operating speeds of 2000-2500 rpm.” The company also displayed a range of demonstrator UAS concepts that integrate the circumferential flux motors, which are nearing the testing phase. The largest testbed system is to be used as a ship-to-shore delivery aircraft by a number of shipping partners in Europe, as well as companies in Greece looking to move freight, medical supplies and documents between small islands. Smaller testbed UAVs have also been developed, for applications such as testing and developing artificial neural network software and delivering blood supplies to rural and outlying clinics far from city general hospitals and blood banks. Frazer-Nash Consultancy attended the expo to showcase the ways it is helping organisations through engineering and r&d to derive greater value from unmanned vehicles. “For example, we’ve recently been working on an AI-driven, smart and autonomous route-planning system for UAVs and UGVs,” explained Holly Baker. “It uses geospatial and situational data [such as weather and vehicle health indicators] to command and control multiple unmanned vehicles at once. Our software optimises the route while avoiding hazards such as buildings, trees and terrain.” Frazer-Nash is also developing bespoke, specialist UAVs for industrial, humanitarian, defence and emergency services applications. In addition, it is supporting organisations who face challenges such as reducing key regulatory barriers for BVLOS operations in UK airspace and other related requirements for wider applications of unmanned aircraft. Mejzlik, in association with Vulcan UAV, showed samples of a new tool- less ‘quick release’ mechanism for its propellers. It is aimed at reducing the time taken to attach and remove propellers from UAVs from a minute per propeller to a few seconds. The mechanism consists of a quarter- turn bayonet-type lock, with a small central lock-shaft in the hub that is pushed down to ‘open’ (or release) the hub, before Commercial UAV Show London 2019 | Show report Unmanned Systems Technology | February/March 2020 AIR6 Systems’ AIR8 survey octocopter Motion Robotics circumferential flux motor