Surviving an In-Flight Anomaly: What Happened on Ingenuity’s Sixth Flight
aristarchus writes:
Flying has never been a safe or precise art. Even when it is not on Mars! Latest from the Ingenuity saga, from NASA it's own self.
On the 91st Martian day, or sol, of NASA's Mars 2020 Perseverance rover mission, the Ingenuity Mars Helicopter performed its sixth flight. The flight was designed to expand the flight envelope and demonstrate aerial-imaging capabilities by taking stereo images of a region of interest to the west. Ingenuity was commanded to climb to an altitude of 33 feet (10 meters) before translating 492 feet (150 meters) to the southwest at a ground speed of 9 mph (4 meters per second). At that point, it was to translate 49 feet (15 meters) to the south while taking images toward the west, then fly another 164 feet (50 meters) northeast and land.
Telemetry from Flight Six shows that the first 150-meter leg of the flight went off without a hitch. But toward the end of that leg, something happened: Ingenuity began adjusting its velocity and tilting back and forth in an oscillating pattern. This behavior persisted throughout the rest of the flight. Prior to landing safely, onboard sensors indicated the rotorcraft encountered roll and pitch excursions of more than 20 degrees, large control inputs, and spikes in power consumption.
[...] Approximately 54 seconds into the flight, a glitch occurred in the pipeline of images being delivered by the navigation camera. This glitch caused a single image to be lost, but more importantly, it resulted in all later navigation images being delivered with inaccurate timestamps. From this point on, each time the navigation algorithm performed a correction based on a navigation image, it was operating on the basis of incorrect information about when the image was taken. The resulting inconsistencies significantly degraded the information used to fly the helicopter, leading to estimates being constantly "corrected" to account for phantom errors. Large oscillations ensued.
Large oscillations are better than small ones, if the truth be told. Godspeed, Ingenuity!
Read more of this story at SoylentNews.