Uncrewed Systems Technology 044 l Xer Technolgies X12 and X8 l Lidar sensors l Stan UGV l USVs insight l AUVSI Xponential 2022 l Cobra Aero A99H l Accession Class USV l Connectors I Oceanology International 2022

106 Report | Oceanology International 2022 Navigator USV, and plugged a USBL system into them. That gives us a precise position of the Seasam when underwater, as well as a GNSS- referenced map of the camera imagery that’s been captured by the Seasam. “That will be incredibly useful for customers who need to perform regular surveys of important assets, such as environmental protection groups who want to go back and check how a particular coral reef or population of fish is doing, or ship owners who want to gauge how the condition of their hulls are changing over time. “To monitor these changes even further, our Notilo Cloud online platform can also be used to automatically analyse survey results and create comprehensive reports.” The Seasam measures 55 x 45 x 23 cm and weighs 9 kg in air. It is powered by swappable batteries that provide 1.5 hours of endurance (upgradeable to 4 hours). This power goes to thrusters that provide 2 knots of maximum forward speed and 1 knot of maximum lateral speed, as well as to a 1/2.8 in CMOS Sony IMX290 low-light camera sensor and two 1000 lumen LEDs to enable clear colour imagery. The vehicle’s DVL enables consistent distance-holding from assets it inspects (such as ships’ hulls) to ensure consistent levels of detail and collision avoidance. Silicon Sensing displayed a number of its latest inertial MEMS devices and products for the autonomous vehicles market. The first of these is the DMU11, which is positioned as the company’s low- cost, six degrees-of-freedom IMU for high- volume applications. “The DMU11 has three gyroscopes as well as six accelerometers – two per axis for dual redundancy,” explained Katie Howard. “It integrates three of our CMS300 MEMS Combi-sensors, each of which contains a dual-axis MEMS accelerometer, and a single-axis gyroscope.” The Combi-sensor has a digital dynamic range of up to ±300°/second, a bias over temperature of up to ±50 m g (at 10 g of acceleration), and a bias instability of no more than 10 º /hour. It draws 8 mA of current on a 3.3 V input, weighs 0.6 g, and measures 10.4 x 6.7 x 2.7 mm. Its gyroscope is constructed using the company’s proprietary vibrating ring structure technology to provide high- quality scale factor correction as well as sustained performance over a wide range of temperatures and inertial rates. Onboard processing for each Combi- sensor is provided through an ASIC installed beneath its gyroscope, and the fully calibrated IMU processing occurs on the OEM PCB that the Combi-sensors are mounted on. “For higher performance applications, we have our DMU41, which we unveiled last year and is about to enter production,” Howard added. “It uses essentially the same sensor technology as our field-proven DMU30 high-performance IMU but with slight improvements in gyro balancing, future- proofing, a 50% size reduction, and other areas including end-user configurability so that customers can now tailor the format of inertial data outputs.” The DMU41 measures 50 mm 3 and consumes up to 125 mA on a 12 V supply. It contains one CRH03 gyro per axis, one PinPoint gyroscope per axis and two Gemini accelerometers per axis (six of each in total) to give bandwidth and error compensation redundancy. Its dynamic ranges are ±490°/second for its gyro outputs and ±10 g for its accelerometers. Also, the gyros’ bias over temperature are ±7 º /hour, while the accelerometers’ are ±1.7 m g . ANB Sensors discussed an advanced type of pH sensor it has developed, which it says stands to make a considerable difference for the large and fast-growing water quality data market. “Existing, conventional pH sensors are built with glass and are very fragile, and on top of that they rely on lengthy calibration before use,” explained Carl Clemans. June/July 2022 | Uncrewed Systems Technology Silicon Sensing’s family of inertial MEMS products