Issue 40 Unmanned Systems Technology October/November 2021 ANYbotics ANYmal D l AI systems focus l Aquatic Drones Phoenix 5 l Space vehicles insight l Sky Eye Rapier X-25 l FlyingBasket FB3 l GCS focus l AUVSI Xponential 2021

57 Space vehicles | Insight Mars NASA’s unmanned systems on Mars are continuing to make progress in their objectives and putting their critical mission subsystems through their paces. As of September this year, the Perseverance Rover had been exploring the Jezero Crater for more than 200 days (in both Earth and Mars terms), studying geological markers and formations for evidence of lava and water flows in the planet’s past. The rover’s autonomous driving has been operating successfully using its two navigation cameras, which periodically perform 360 º sweeps to perform mapping and localisation when it has stopped. Over the course of the Jezero exploration, numerous other onboard cameras have been critical to recent geological findings. For example, the Mastcam-Z system, which consists of two 1.38 kg, 1600 x 1200 zoom cameras, has supplied panoramic and 3D colour imagery to help identify ideal spots for rock-sampling, particularly when cross-referenced with terrain images taken from orbit by the Mars Reconnaissance Orbiter. Also, the rover’s SuperCam payload integrates two lasers and four cameras – including an IR spectrometer and a Raman spectroscope – which are key to measuring the chemical and mineral composition of the Martian rocks. The rover’s sensors have subsequently provided clear signs of volcanic activity, including lava flows. They have also found evidence that the Martian atmosphere was once thick and warm enough for water to flow across the surface, with former river deltas and lake beds showing signs of flash flooding. Meanwhile, the Ingenuity helicopter that was carried with the rover is continuing its flight trials to gauge the potential for future UAV deployments to Mars. Its most recent milestone was a high- speed rotor spin test, which was key to identifying its ability to fly in the Red Planet’s atmosphere when it thins owing to seasonal changes. The test was carried out in mid- September this year, with the craft’s two electric motors (provided by Maxon Motor) spinning at up to 2800 rpm. The speed was maintained briefly, before the rotors slowed to a stop, all as per planned test procedures and without any potentially harmful resonances being detected in the airframe. There was, however, a test flight scheduled for September 18, which was intended to consist of a brief hover at an altitude of 5 m with a 2700 rpm propeller speed, but which did not take place. The UAV detected a roughly 1 º oscillation in two of its flight control-critical swashplate servos during its automatic pre-flight checks, and autonomously chose to cancel the flight, as per safety protocols. One possible reason put forward for the oscillations is wear incurred from Ingenuity having already performed 13 flights (only five had been originally planned for the mission duration thus far). Another is that the high-speed tests put the upper rotor in a position that is inducing different loads into the servos from before. Analysing the cause(s) will be performed through to mid-October, as Mars is in solar conjunction until then, the sun blocking NASA’s ability to uplink new command sequences to the helicopter or rover. Ingenuity meanwhile will continue delivering system health data to its base station on Perseverance, which will be transmitted to Earth once the solar conjunction ends. The Solar System Scientific exploration missions are also continuing elsewhere in the Solar System. Earlier this year, NASA’s Juno spacecraft flew within 1040 km of Ganymede, the closest any probe has ever come to this moon of Jupiter and the Solar System’s largest. The JunoCam payload took numerous photos of Ganymede’s surface, which have since been transmitted back to Earth and will help inform the upcoming JUICE (JUpiter ICy moons Explorer) mission. This will be launched in June next year aboard an ESA Ariane 5 rocket and aims to further explore Ganymede, Europa, Callisto and Jupiter itself. Two months later, NASA will launch an unmanned solar-electric probe of its own towards the Psyche asteroid, which sits between Mars and Jupiter. Psyche is suspected to resemble the kind of nickel- iron core typical of an early planet. Unmanned Systems Technology | October/November 2021 The Perseverance rover’s Mastcam-Z payload has transmitted numerous panoramic and 3D colour images back to Earth, of potential rock-sampling sites and of the Ingenuity helicopter shown here (Courtesy of NASA)