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52 Report | AUVSI Xponential virtual 2020 data, CAN interfaces, wheel sensors and more beyond just a Kalman filter working with data from an IMU, a magnetometer and a GNSS receiver.” While the u-blox GNSS receiver provides RTK positioning accurate to 1 cm and supports a range of GNSS constellations (including GPS, GLONASS, Galileo and BeiDou), the aiding and dead-reckoning features are complemented by Inertial Labs’ miniAHRS solution. In addition to three-axis accelerometers and gyroscopes, as well as the company’s proprietary algorithms for motion control on unmanned and autonomous vehicles, and antenna pointing platforms, the miniAHRS incorporates a mini three-axis fluxgate magnetometer. Together, these features provide distinct advantages over more commonly used magneto-resistive alternatives in terms of accuracy, especially over an operational temperature range. The overall INS-DU system weighs 320 g, with a housing measuring 120 x 50 x 53 mm, and uses 5 W during standard operation. Mejzlik Propellers has developed a propeller calculator tool that draws on its volumes of internal testing data. It can calculate the required static thrust for multi-copters based on customers’ inputs for components and mission variables. “We’ve long been faced with a huge number of questions as to how our propellers work, and the calculator was released to help answer some of those questions – particularly for mechanical engineers who are developing UAVs but lack specific expertise on propellers,” said Tomas Mejzlik Jr. For especially accurate predictions, end-users can feed in data on their UAV, its battery specifications, electric motors and motor controllers. The calculator will then interpolate or extrapolate how the thrust and power outputs will change as customers simulate different propeller diameters, pitches, numbers of blades and altitudes. As standard, the calculator provides graphs detailing key relationships and trade-offs for the use-case, such as how power consumption changes with propeller diameter, how thrust changes with mechanical power, or how endurance changes with pitch. “Most calculators out there are based on simulated data, so they’re not very accurate, but we’ve addressed that by using our archives of measured data to ensure that the margin of error never exceeds 5%, and also by enabling calculations of how aircraft powertrain outputs change according to key factors that other calculators don’t account for, such as MTOW, battery capacity and motor efficiency,” Mejzlik added. “We also have a calculator to estimate the dynamic thrust for fixed-wing aircraft propellers. While that one is currently based on simulated data, by the middle of this year we plan to have replaced that with measured data on our fixed-wing prop tests to achieve equivalent accuracy with the static thrust calculator.” We spoke with H3 Dynamics, which has developed a cloud-based ‘software as a service’ for professional visual inspection reports, called H3 Zoom. Its first subscription service was launched a year ago for detailed aerial inspections of building facades, including automated flight paths for UAVs as well as visual analytics capable of distinguishing between 31 types of building defects with different severity levels. “H3 Zoom started out as a research project for hydrogen-powered flight,” said Taras Wankewycz. “While developing the charging infrastructure for autonomous drone installations, we found we were gathering large amounts of visual data on the nearby infrastructure, and we wanted to find ways to sort through that data faster with a view to better delivery of our services. So we developed AI software to identify and report on the specific details we were after. “Cloud computing enables us to leverage low-cost mass computing power to crunch through huge quantities of image and video data. Over December/January 2021 | Unmanned Systems Technology Mejzlik’s propeller calculator, for calculating the required thrust for multi-copters