NASA said Monday the Ingenuity helicopter needs a software update to resolve a problem that cut short the drone’s rotor startup sequence on Mars last week, postponing the craft’s first flight in the Red Planet’s atmosphere until later this month.
The helicopter — set to try to become the first craft to perform powered flight in the atmosphere of another planet — aborted an attempted spin-up of the its counter-rotating blades Friday after its autonomous control software detected a problem.
The lightweight helicopter was programmed to power up its rotors to flight speed near 2,500 rpm for a final pre-flight checkout Friday, leading to an attempt at a first flight Sunday, April 11. But the premature end to the high-speed spin test prompted ground teams to delay Ingenuity’s first test flight to no earlier than Wednesday, April 14.
In an update released late Monday by NASA’s Jet Propulsion Laboratory, mission managers said engineers identified a software fix for the “command sequence issue” that ended the high-speed spin-up test Friday.
Officials at JPL, which manages the Ingenuity helicopter project, did not announce a new target date for the rotorcraft’s first test flight. Ground teams hope to determine a new target date next week for the helicopter’s first flight.
Ingenuity is a small robot drone with a mass of just 1.8 kilograms (4 pounds on Earth or 1.5 pounds in Martian gravity) that rode to Mars on the belly of NASA’s Perseverance rover. Perseverance landed on the Red Planet on Feb. 18 with a primary objective of locating, collecting, and sealing rock specimens for return to Earth by a future mission.
NASA tacked on the $80 million helicopter as a technology demonstration, and agency officials gave Ingenuity 31 days to complete its flight experiments from the time Perseverance deployed the rotorcraft from its belly April 3.
Since then, the six-wheeled rover has driven to an observation location roughly 200 feet ( 60 meters) from Ingenuity’s flight zone. Perseverance will try to take pictures and video of Ingenuity’s first flight, which engineers expect will last around 40 seconds as the drone takes off to an altitude of about 10 feet (3 meters), momentarily hovers there, then rotates to point in a different direction before landing back on its four carbon-fiber legs.
If the first flight is as successful as NASA hopes, Ingenuity could fly four more times in subsequent weeks, trying more daring flight profiles before wrapping up the test flight campaign in early May.
Since separating from the rover April 3, the helicopter has demonstrated it can survive on its own power generated through a small solar panel. Ground teams also successfully unlocked the rotor blades, spanning nearly 4 feet (1.2 meters) tip-to-tip, for a low-speed spin test of 50 rpm last week.
The command sequence for the high-speed spin test Friday ended early as the helicopter was trying to transition the flight computer from “pre-flight” to “flight” mode, according to NASA. A watchdog timer system designed to oversee the command sequence expired before the completion of the spin test, ending the helicopter’s pre-loaded command sequence.
NASA said Monday that engineers over the weekend decided they will reinstall Ingenuity’s flight control software with a “minor modification” to the process that boots up the helicopter’s two flight computers. The change will allow the helicopter’s hardware and software safely transition to the flight mode, officials said.
Ground crews at JPL are reviewing and validating the software update in testbeds over the next two days.
Once that is complete, engineers will take “careful and deliberate steps” to upload the new software to the Perseverance rover. Perseverance has a radio base station that routes all communications between Earth and the Ingenuity helicopter.
Finally, the updated software will arrive on Ingenuity for installation into the flight computers. Then the helicopter will be ready to boot up using the new code.
“Once we have passed these milestones, we will prepare Ingenuity for its first flight, which will take several sols, or Mars days,” NASA said Monday. “Our best estimate of a targeted flight date is fluid right now, but we are working toward achieving these milestones and will set a flight date next week.
“We are confident in the team’s ability to work through this challenge and prepare for Ingenuity’s historic first controlled powered flight on another planet,” NASA said.
Ingenuity is otherwise healthy with stable power, communications, and thermal control to guard against the frigid nighttime temperatures on Mars.
“It is not unexpected for a technology demonstration like this to encounter challenges that need to be worked in real time,” NASA said. “The high-risk, high-reward approach we have taken to the first powered, controlled flight on another planet allows us to push the performance envelope in ways we could not with a mission designed to last for years, such as Perseverance.”
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