Unmanned Systems Technology Dec/Jan 2020 | Phoenix UAS | Sonar focus | Construction insight | InterGeo 2019 | Supacat ATMP | Adelan fuel cell | Oregon tour | DSEI 2019 | Copperstone Helix | Power management focus

Power4Flight and Cobra Aero are working on the A99i, a triple-inline liquid-cooled two-stroke engine which will be produced mainly through additive manufacturing and be able to run on heavy fuels 72 Tech tour | Oregon as double the shaft power output using electric boost. “A lot of other features we want for this engine are perfectly matched for the triple-inline, water-cooled topology. For example, we want to spark-ignite heavy fuel, which you can’t really do with one big cylinder, so three 33.45 cc cylinders provide an ideal architecture for that. “We also want to minimise noise and vibration. The primary reason for vibration in single-cylinder engines is torque ripple, so spreading that across three points per crankshaft revolution [thanks to having three cylinders in line] really helps make it quieter and vibrate less. “Liquid cooling will also help reduce the host UAV’s drag compared with air cooling, since you can position the radiator as you need to streamline the airframe. It is easier to add active cooling as well, which is important for customers who want a UAV that can hover for extended periods.” Also, the complexity of the engine’s design – particularly regarding the pistons, exhaust system and liquid- cooling jackets – mean the A99i will be manufactured largely using additive manufacturing for series production. “Because of the size and complexity of the water passages throughout almost all the components, it’s much more reasonable to print them, because casting and CNC would pose serious challenges to getting them right,” Vaglienti explained. Overwatch Imaging The final meeting in Hood River took place at the offices of Overwatch Imaging, where Greg Davis updated us on the progress with his company’s specialised automated imaging payloads. Its solutions are designed to process photogrammetric multi-spectral imagery onboard in real time, using GPU- accelerated hardware and proprietary computer vision software. The survey data is also stored with associated metadata for post-processing as well as further analysis and archiving. “Our automated land surveillance systems are being developed and matured, especially through field work with the National Oceanic and Atmospheric Administration and Mississippi State University. They are using the TK-5 Earthwatch imaging system on a Griffon UAV for river and flood monitoring, as well as with industry leaders such as Insitu and Textron,” he said. “We’re also continuing to expand our software capabilities in intelligent fire December/January 2020 | Unmanned Systems Technology Image of Hood River, Oregon, taken on a TK-5 Earthwatch system during flight testing for a customer involved in anti-poaching operations in Africa (Courtesy of Overwatch Imaging)