Uncrewed Systems Technology 049 - April/May 2023

78 Show report | IDEX 2023 instance, our Autosub 5 uses four Volz actuators in a cross-form set of control fins and it has operated at depths of 4840 m, on the Porcupine Abyssal Plain, with the servos working just fine for the duration.” The NOC reported having previously used electromechanical linear servos made in-house, but found them prone to lock-ups, corrosion and general reliability problems. After some research into replacements, it went with the Volz DA 26-SUB, an oil-filled electromechanical rotary actuator rated to 28 V. It can deliver up to 5 Nm of peak torque, operate in temperatures from +70 to -30 oC, and has an aluminium housing rated to last for at least 1000 hours of saltwater exposure. In addition to its housing compensating against ocean depth pressures that could otherwise crush the servo’s internal systems, the DA 26-SUB integrates a semiconductor clock on its PCB, as standard oscillators are typically quite vulnerable to pressure-related damage. It also integrates a special PCB designed to withstand extremely high pressures to serve customers such as the NOCwho want to perform surveys down to 6000m. Also, while using this servo, the Autosub Long Range was able to achieve the world record for the longest autonomous submarine deployment, having travelled for 2000 kmduring a 6-week journey that began in the summer of 2022. “Filling an actuator with oil means that water doesn’t leak in, and it’s insulated against electrical arcing,” Kingsland added. “Also, crystal oscillators generally stop pulsing correctly at depths of around 3500 m, so Volz went with an alternative that we recommended. “And because of the strong waves we can face during our missions, the actuator has an overload device for disconnecting itself when too much wave force impacts them, thereby mitigating damage to the geartrain and capacitors.” The Autosub Long Range has maximum ratings of 6000 m depth and 2000 km range. It carries out primarily environmental monitoring, particularly water property measurements such as conductivity, temperature and salinity sensing rather than sonar scanning. The surveys around the Thwaites Glacier are part of the TARSAN (Thwaites-Amundsen Regional Survey and Network Integrating Atmosphere- Ice-Ocean Processes) project to study how atmospheric and oceanic processes influence the differing behaviours of Thwaites and its immediate neighbour, the Dotson Ice Shelf. MKS Instruments, through its Ophir Optronics brand and subsidiary, unveiled a new addition to its LightIR family of low- SWaP, motorised continuous zoom IR lenses, the Ophir LightIR 18-225mmMWIR f/4 product. It is optimised for use with 10 µmpixel SXGA/HD FPAs (focal plane arrays) and 15 µmVGA FPA detectors. “The new zoom lens addresses the recent market shift toward smaller pixel size IR detectors,” said Dr Kobi Lasri at Ophir Optronics. “Its cost-versus- performance ratio is intended as an enabler for advanced tactical UAV and small gimbal thermal imaging applications.” The lens’ optical elements have been designed to minimise its length and weight in order to reduce the length of any optical system integrating it. Its total weight is 326 g, it is 86 mm long and its diameter is 61.4 mm, with the housing providing IP67 protection to the front element. It can be operated in temperatures from -32 to +75 oC, and consumes up to 1 A peak current (or just below 0.5 A in standard operations) on a 12 V input, with data output over RS422. If paired with a 10 µmdetector at 1280 x 1024, its FoV ranges from3.3 to 39.1 o. When using a 15 µmpixel pitch detector and configured for 640 x 512 imaging, the lens provides amaximumFoV of 29.9o and an FoV of 2.4o at maximum focal length. The electric motor in the lens enables it to go frommaximum to minimum zoom in just under 5 seconds, with a focus time of just below 2 seconds. Autel Robotics showcased its newest UAV, the EVO Max 4T, which it has developed for applications including commercial operations such as mapping and industrial inspection, emergency services such as search & rescue, firefighting surveys and public safety monitoring with police. April/May 2023 | Uncrewed Systems Technology Ophir’s LightIR 18-225 mmMWIR f/4