Issue 41 Unmanned Systems Technology December/January 2022 PteroDynamics X-P4 l Sense & avoid l 4Front Robotics Cricket l Autonomous transport l NWFC-1500 fuel cell l DroneX report l OceanScout I Composites I DSEI 2021 report

UAV Factory Octopus ISR Systems An autonomous robot is using Doppler velocity logs (DVLs) – normally used for velocity calculations in subsea applications – for inspecting the contents of fuel tanks (writes Nick Flaherty). The system, from Square Robot, is designed to fit through the 24 in-diameter ‘manway’, the standard size of portal fitted to the top of storage tanks that are typically up to 30 m tall and can be 15 to 80 m in diameter. “The robot essentially performs a floor inspection of the tank that would otherwise have to be done by a human,” said Amy Underwood, senior roboticist at Square Robot. “During a traditional out- of-service inspection, the tank is emptied, cleaned to make it safe for entry, then inspected by personnel. All this downtime means a significant loss of revenue for the tank owner, but our robot gets rid of all that.” The robot uses four DVL1000 loggers from Nortek to provide location information by measuring the shift in wavelength between acoustic pulses transmitted to and reflected back from particles in a liquid, in this case gasoline. The key is that the accuracy of the measurements means the robot can operate up to 20 cm from the bottom of the tank. DVL petrol tank inspection Sensors Square Robot’s system allows tanks to be inspected while they are still full of fuel