81 The largest is a 6S4P system that weighs 2508 g, with 42.4 Ah in capacity, 864.96 Wh of energy stored, and dimensions of 155 x 65 x 160 mm. All four systems have a nominal voltage of 20.4 V (with 2.5 V per cell) and can discharge at a rate of 4C. Sandvik Osprey exhibited at the expo for the first time to show its controlled expansion alloys and their effectiveness for use in components undergoing extreme temperature changes. “They’re made from a binary aluminium-silicon alloy, and by changing the ratio of the metals we can change the thermal expansion degree of the alloy, tailoring it from anywhere between 5 and 17 ppm/K, with anything from 27% silicon up to 87% silicon,” said Dr Stuart Sillars. “We can also vary it to match any material that has a CTE [coefficient of thermal expansion] of between 5 and 17, be they metal alloys, semiconductor wide-bandgap materials or even PCBs. Any assembly or component that is sensitive to a wide range of temperature changes, for example from room temperature to the Arctic, will need mounts with the same CTE.” Typical CTE-matching materials tend to be far denser and heavier than Sandvik Osprey’s Al-Si alloys, for example molybdenum or tungsten-based materials such as copper-tungsten in space vehicles (with which the company’s Al-Si alloy has extremely close thermal conductivity, but with one-sixth the weight). “Casting our alloys is rarely possible with more than 15% silicon, but we get around that by rapidly solidifying our material from its molten state to produce a material with a fine and homogeneous microstructure, and we can then make CNC or EDM components from the billet,” Dr Sillars added. Sierra-Olympia Technologies discussed a range of new IR cameras supplied by it and the partner companies it represents. First was Jenoptik’s EVIDIR Alpha, designed as a small form factor, calibrated, radiometric microbolometer system for inspection-type UAV and other industrial applications requiring temperature readings. “It’s a LWIR, 12-micron system with VGA at 640 x 480 resolution, and at the moment there are three available lens configurations. On top of that it can be configured for CMOS or CameraLink, and MIPI interfacing is expected in 2024,” said Chris Sculley. “In addition, the latest release from Leonardo DRS – for whom we’re the North American master distributor Uncrewed Systems Technology | October/November 2023 Component made from one of Sandvik’s controlled expansion alloys Sierra-Olympia’s Ventus HD6-2.4 is designed as a low-SWaP, HD, long-distance zoom IR camera for uncrewed systems
RkJQdWJsaXNoZXIy MjI2Mzk4