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8 Platform one Lidar USA has integrated both the CL-90 and CL-360 Lidar sensor payloads from Teledyne OpTech into the Galaxy 950 UAV from InnoFlight in Australia (writes Nick Flaherty). The G950 is a single-rotor helicopter system with a 6 kg maximum payload and a take-off weight of 21 kg. It has a proprietary autopilot made in Taiwan, with no cybersecurity issues, no data transmission and no auto updates. It uses a dedicated paired GCS and so is aimed at operators with security concerns, said Jeff Fagerman, CEO of Lidar USA. The CL-90 is targeted specifically at aerial applications, particularly for corridor mapping. The scanner system has a scanning FoV of 64-90 º with a sawtooth scan pattern up to 50 Hz and a maximum data rate of 500 kHz. The scanner delivers up to four returns using a 0.3 mrad beam, making it better able to Researchers at MIT have developed a trajectory planning model that helps UAVs fly at high speeds through previously unexplored areas (writes Nick Flaherty). The model, called Faster, estimates the quickest path from a starting point to a destination point across all areas a UAV can and cannot sense but initially without regard for safety. As the UAV flies, the model continuously logs collision-free back-up paths that deviate slightly from the fastest flight path and then adds in safety data. When the UAV is unsure about a particular area, it takes a detour down a back-up path and re-plans its path. A craft can cruise at high speeds along the quickest trajectory, while occasionally penetrate vegetation than other systems. It can also be used from a height of more than 600 m, making it suitable for UAV and helicopter applications. The integration of the CL-90 required a leg extension to get extra height to accommodate the sensors, and the mount includes dampers to reduce vibration. Mounting the system also slowing down slightly to ensure safety. “We obtain a higher velocity trajectory that may not be safe and a slower one that’s completely safe,” said Jesus Tordesillas, a graduate student in the Department of Aeronautics and Astronautics at MIT. “The two paths are stitched together at first, but then one deviates for performance and the other for safety.” A Faster-enabled UAV uses cameras to capture the environment as voxels – 3D cubes generated using depth information. As the craft flies, each voxel is labelled ‘free known space’ – unoccupied by objects – and ‘occupied known space’, which contains objects. The rest of the environment is ‘unknown space’.  The model plans a safe trajectory, required running a cable towards the rear rotor, said Fagerman. All the scan data is stored on an external USB on board the scanner and is easily removable. The data is all post-processed and ready for further analysis using Lidar USA’s software shortly after landing. The CL-360 is similar but has a faster scan line rate, of 250 Hz, and a 360 º FoV. plotting a rescue point that indicates the last moment a UAV can take a detour to free known space, based on its speed and other factors. To find a safe destination, it stops at a spot that’s safe but as close as possible to unknown space, enabling a quick and efficient detour. The committed trajectory consists of the first interval of the whole trajectory, as well as the entire safe trajectory. But this first interval is independent of the safe trajectory, and is therefore not affected by the braking needed for the safe trajectory. The team designed ways for the UAV to process all the planning data very quickly, which was challenging. Because the maps are so varied, for instance, the time limit given to each committed trajectory initially varied dramatically. Airborne vehicles Airborne vehicles Aerial Lidar integration A Faster way through February/March 2020 | Unmanned Systems Technology x Lidar USA has integrated Teledyne OpTech’s CL-360 into an InnoFlight Galaxy 950 UAV (Courtesy of Lidar USA)