Unmanned Systems Technology 033 l SubSeaSail Gen6 USSV l Servo actuators focus l UAVs insight l Farnborough 2020 update l Transforma XDBOT l Strange Development REVolution l Radio telemetry focus

96 that are secure enough to withstand the shock-loads of launching the Penguin C. “It takes around 5 minutes at most to assemble or disassemble the catapult,” Popiks says. “All its pieces, as well as the compressed-air tank, fit into a box the same size as the UAV’s, enabling quick transport to the nuclear plant in whatever road vehicle is available. “A UAV’s logistical footprint multiplies the cost of using it at every step of operations. For that reason we designed this system to need no more than two people to transport and operate it, and we supply our catapult to a number of UAV manufacturers around the world who want a small catapult to suit their smaller aircraft.” Mapping radiation Although regulations in Japan currently restrict the flight ceilings of UAVs to 150 m, the Penguin C could probably fly higher than that during its survey missions. Given the experimental nature of this project, among the many unknowns is which type (or types) of radiation detector to use. Since Clear Pulse produces many kinds, and time would be of the essence in the event of a nuclear disaster, it remains to be seen which sensor will be deemed the first priority for integration. For example, ionisation detectors – a widely used type of radiation sensor produced by Clear Pulse – carry an internal chamber filled with air or some other gas that can be ionised by radiation. When the particles within become ionised (as positive or negative ions), they migrate towards their polar-opposite electrodes, resulting in an electrical pulse. Once these pulses are amplified, they can be recorded and measured for radiation information. Alternatively, the UAV might integrate Clear Pulse’s semiconductor detectors. These work similarly to ionisation chamber detectors, but at a scale and voltage similar to MEMS devices. They are designed with two layers of semiconductor material, one with a higher negative ion count than the other, so the ions migrate from the former to the latter. As the particles move, any radiation present will re-ionise them, producing a measurable electrical pulse. These sensors tend to produce faster detection times and can withstand higher levels of radiation than many other types of radiation detector (and are the smallest type, measuring around 4 x 4 x 1 mm in some cases). These factors make them potentially ideal for this application. The type and level of radiation measured can be stamped with the time, altitude and GNSS coordinates recorded by the Piccolo flight computer. These are then combined with additional geo- referencing systems using extensive post-processing at Clear Pulse’s ground control centre, to produce a 2D or 3D map of a radiation plume. Over two or three days, the process can be repeated to get enough of an idea of how the plume might be expanding or moving. The authorities can therefore determine which nearby towns or villages need to be evacuated first, and where the people should go to be able to give the plume a wide berth. During the evacuation process, the Penguin C can also be equipped with one of Octopus ISR Systems’ EO/IR/laser payloads to help monitor and coordinate the safe and orderly movement of civilians away from the nuclear plant. Recovering the Penguin C The Penguin C typically deploys a parachute in order to land, forgoing the need for any net or hook-type system for recovery, in line with the aforementioned design emphasis on logistical ease. Future testing will determine exactly August/September 2020 | Unmanned Systems Technology Regulations in Japan limit UAVs to 150 m altitudes, but the Penguin C may obtain special dispensation to fly higher, to determine the extent of radiation spread (Courtesy of UAV Factory)