Uncrewed Systems Technology 043 l Auve Tech Iseauto taxi l Charging focus l Advanced Navigation Hydrus l UGVs insight l MVVS 116 l Windracers ULTRA l CES 2022 show report l ECUs focus I Distant Imagery

113 Distant Imagery | In operation is ongoing, but has played out similarly to the planning stages of the project. First, considerable effort has gone into manually inspecting and counting the number of successful seedlings. Distant Imagery has found empirically that the seeds launched from its UAVs have a 35-42% chance of growing into viable mangroves, variations typically coming from geography across each site. To the uninitiated that might look like a low figure, but the average mangrove natural regeneration rate is about 5%. Distant Imagery’s far higher figure is largely thanks to the pre-planting surveys and so on that go into planning its UAVs’ flight and distribution routes. “We’ll also measure the soil and water environment to make sure nothing detrimental is found in them,” Glavan says. “Then we’ll orthomap with the UAVs again, using the same sensors, routes, altitudes and speeds as in the planning surveys. Again, repeatability is everything, including having valuable before/ after ortho imagery for gauging how successful we were.” Rhodes adds, “There will be at least 5-10 years of intermittent checks after a restoration project, to gauge whether it was truly successful, as mangroves outside the correct inundation band probably wouldn’t make it past a few years. But the Mirtha lagoon is already showing very positive signs, with saplings springing up in good numbers, and in future projects we’ll improve further on that in a few ways. “One is by using germinated seeds more than seed balls; we’ve found that the former give a better success rate. Another is that we’ll use a wider diversity of seeds where appropriate, as diverse ecosystems can only be truly sustained through polyculture planting. If one plant consumes nitrogen in the soil for instance, another needs to replenish it using nitrogen drawn from the air.” Future plans Distant Imagery expects to continue its efforts in the Gulf region and elsewhere. In addition to extensive UAE government support and consultation (through the EAD), the funding from Engie formed the team’s budget for the Mirfa lagoon’s restoration. Pending further funds from other groups, they anticipate being able to accelerate, expand and refine their reforestation capabilities. “Given enough budget, we’d really like a pairing of long-endurance heavy-lift multi-copters with VTOL transitioning, and fixed-wing heavy-lift UAVs with a low stall speed, maybe powered by hydrogen for zero emissions, long endurance and high payload power,” Rhodes says. “Those could integrate laser altimeters for gauging water depth and maintaining set altitudes above the surface, with solid- state Lidar from LeddarTech, Velodyne or Terabee for forward observation, hyperspectral cameras for plant health, and high-end ESCs and distribution boards for stable power. “We could also exploit machine learning to develop computer vision or analytics for Lidar and vision, or use something like Skydio 2+ with built-in AI, to gauge the softness of mud below the UAV, then estimate how well the seeds will sink into different stretches of soil. “It could also enable obstacle avoidance to slalom carefully around or over pre-existing mangrove trees even down to the ground, for deeper and more accurate seed dropping and hence an even higher rate of survivability. Computer vision could also autonomously identify, count and geo-tag which seeds have taken root and where the saplings are.” Until that budget is achieved, however, the team will continue to develop its own solutions, or make use of components donated by environmentally conscious suppliers. Equipment donations are increasingly common among sustainability oriented projects, as with the Mayflower Autonomous Ship (see UST 42, February/March 2022). “And now that our rigging payload has proven effective, as is the case for adopting our approach over traditional reforestation methods, we’re looking forward to going back to many of the developing communities we studied while formulating our tech so that they can try it themselves,” Glavan adds. “By keeping it simple, with accessible and easily replaceable components, we hope to work with community replanting efforts across the world to train their teams in using our systems. Our engineering can be understood and self-sustained by anyone, not just UAV mechanics but any ecological workers, to multiply their planting rates and germination rates while hugely reducing the cost and labour of reforestation.” Unmanned Systems Technology | April/May 2022 Previous equipment Autopilot: DJI A3 Pro GCS: Lightbridge 2 with channel expansion kit Currently migrating to Autopilot: Pixhawk GNSS: Here Pro Antennas: Herelink GCS: Herelink Optical flow camera: Hereflow TOF sensor: Terabee Power distribution board: Airbot Power distribution board: Spektreworks Standard components regardless of airframe Servos: COTS Motors: T-Motor NDVI cameras: Mapir Map processing software: Pix4d Map processing software: Dronedeploy GCS software: UGCS Portable RTK GPS: EMLID Additive printing: SeeMeCNC Additive printing: Creality Equipment shipping: Foxtech Some key suppliers