Unmanned Systems Technology 005 | Selex ES Falco UAV | Sense and avoid systems | RCV Engines DF70 | DSEI show report | Fuel cells | CUAV Expo, InterDrone and CUAV Show reports | SLAM

40 Focus | Sense and avoid systems evasive manoeuvres, and the hardware requirements are such that it will fit with current avionics standards approvals when it’s available for UAVs, which will be in the next five years. This visual system has the added advantage of helping with the wider sense and avoid challenge of weather conditions. The second processor core is being used to identify weather fronts and other related risks to the aircraft, and feed this data into the autopilot to provide an alternative direction of flight. This is also being linked to a mapping database on the aircraft that highlights areas where the craft cannot land in an emergency, such as built-up areas or power pylons, and identifies a safe area within the glide path of the aircraft for landing. They can then be used to identify any moving objects within the potential landing area to highlight obstructions. The project highlights another SWaP challenge for sense and avoid systems. Installing camera sensors in an airframe can increase its weight, as the holes for the sensors have to be reinforced. This may mean that having an array of sensors in one location replacing the view that a pilot would have is a lighter solution than separate sensors spread out across the airframe. This trade-off between sensor arrays and visibility will be key in future designs, although the single array meets current regulatory requirements. Another approach being developed is to use sensors that remove the static background from the CMOS array, highlighting any movement. This could be used to identify the movement of aircraft underneath a UAV against the ground, which is a key challenge for sense and avoid systems that tend to assume a background of the sky. Cloud computing A very different approach to the sense and avoid challenge is being taken by systems that use cloud computing resources linked to apps on a smartphone used to control smaller craft. A leading quadcopter developer has updated its app to check the location of the smartphone via the phone’s GPS sensor. The location is sent back to a database in the cloud, and if the phone is in or close to a no-fly zone the quadcopter will be grounded and the operator notified. This can work with fixed no-fly zones, such as those around airports, and temporary zones such as wildfires. Quadcopters taking video have previously interrupted fire-fighting aircraft, which cannot operate without risking a collision with these craft. The benefit here is that the no-fly zones can be constantly monitored and updated via the cloud. However, this approach can struggle if the smartphone is not the controller, if it is a significant distance away, if the link to the cloud fails or if the GPS location monitoring is switched off or deliberately changed (‘spoofed’). Other cloud-based approaches are even more ambitious. One aims to give every UAS a unique identifier, and linking the craft to the internet using mobile phone technology allows the cloud to automatically monitor every craft in the air and issue avoidance instructions to any of those craft when required. Every craft in the network has its own globally unique identifier that is linked with position data from the craft’s GPS navigation sensor. This combination of identifier and position data is Dec 2015/Jan 2016 | Unmanned Systems Technology BAE Systems in the UK used a manned aircraft to test out a camera tracking system for sense and avoid applications under the European Astraea programme that finished in September 2015