After some long-range troubleshooting, NASA’s Ingenuity Mars helicopter will attempt to make the first flight of its kind on another world on Monday in a demonstration that could open the door to a new era of interplanetary aerial reconnaissance.
Engineers at NASA’s Jet Propulsion Laboratory in California sent the commands for Ingenuity’s test flight on Sunday via an uplink, paving the way for takeoff with a short up-and-down jump Monday at 3:31 a.m. EDT ( 0731 GMT).
It takes nearly three hours for ground teams to receive data confirming the outcome of the flight. The signals will bounce from the helicopter to the Perseverance rover, which the drone released on the surface of Mars on April 3, and then to a flying orbiter to send the data back to Earth.
NASA TV will broadcast live coverage from JPL’s operations center starting Monday at 6:15 a.m. EDT (1015 GMT) as officials await data on the results of Ingenuity’s hops. Once the data starts to flow, engineers will analyze the signals for the telltale signature that the helicopter successfully took and landed.
Afterwards, the images will be streamed back to Earth from cameras on board Ingenuity and cameras on the Perseverance rover, which is observing the flight from a distance of about 60 meters.
NASA officials expect the fully automated flight to take about 40 seconds on Monday, as the drone takes off to a height of about 10 feet (3 meters), hovers there for a moment, then spins to point in a different direction before landing again. are four carbon atoms. fiber legs.
The first images from the helicopter’s black-and-white navigation camera could return to Earth shortly after the test flight on Monday. Then the craft goes to sleep and charges its batteries before sending color images.
Meanwhile, a zoomed-in high-definition camera mounted on the Perseverance rover’s mast will attempt to capture still images and video from the helicopter flight.
“We are very excited,” said Tim Canham, JPL’s Head of Ingenuity. “It could be a great day. We are all nervous, but we are confident that we are putting in the work and time and that we have the right people to do the job. “
If the maiden flight is as successful as NASA hopes, Ingenuity could fly four more times in the following weeks and try out more daring flight profiles before the flight test campaign concludes next month. Next, NASA wants to free up persistence to continue with its primary scientific mission of finding and collecting samples of Martian rock for eventual return to Earth.
Lori Glaze, head of NASA’s planetary science department, described the Ingenuity helicopter as a high-risk, high-reward experiment that could pave the way for future aerial vehicles to explore Mars and other planets.
The $ 80 million Ingenuity helicopter has a mass of just 1.8 kilograms. It weighed 4 pounds on Earth, or 1.5 pounds in Martian gravity, but its lightweight blades will have to generate lift in an atmosphere less than 1% of Earth’s density at sea level.
Bobby Braun, JPL’s director of planetary science, said the helicopter and its support team will try to produce a “Wright Brothers’ moment” back on Earth in another world.
NASA recognized Ingenuity’s flight as a new aviation first and installed a piece of cloth the size of a postage stamp from the Wright brothers’ first plane, known as the Flyer, on the Mars helicopter. The fabric covered one of the aircraft’s wings during its maiden flight in Kitty Hawk, North Carolina, on December 17, 1903.
Another piece of cloth and a fragment of spruce from the Wright Flyer flew to the moon during the Apollo 11 mission in 1969. While the Wright brothers used cloth and wood for their planes, Ingenuity is made of carbon fiber skins and “exotic metals,” said Bob Balaram, Ingenuity’s Chief Engineer at JPL.
Thomas Zurbuchen, chief of NASA’s science department, called Ingenuity’s first flight attempt “a historic moment that analogues have in 1903 – controlled flight on another planet.”
Since Perseverance deployed the Ingenuity helicopter from its belly earlier this month, the rotorcraft has proven it can charge its batteries with a solar panel and stay warm in the frigid Mars night. Ground teams also sent commands to release the rotor blades, which span nearly four feet from point to point, for a low-speed 50 rpm rotation test.
But a problem ended the drone’s launch sequence on Mars during an attempted rapid spin-up on April 9. The rapid spin test of Ingenuity’s counter-rotating blades would be a final checkout before officials proceeded to the helicopter’s maiden flight, then scheduled for April 11.
The high-speed test sequence ended early when the helicopter attempted to switch the flight computer from “pre-flight” to “flight” mode, NASA said. A watchdog timer system designed to monitor the command sequence expired before the spin test was completed, prematurely ending the helicopter’s spin test.
Teams at JPL have come up with two tactics to solve the command sequence issue. According to MiMi Aung, Ingenuity’s project manager, there is one approach where the order of commands is changed to “slightly change the timing” of the helicopter’s transition from pre-flight to flight mode.
The other solution is a disruptive motion that would further delay the helicopter’s maiden flight. That option is to reinstall custom software on Ingenuity’s flight computer, replacing code that has worked perfectly for the helicopter for nearly two years, Aung wrote in a post on NASA’s website.
Trying out the flight using the modified command sequence is easier, and it worked Friday during a successful high-speed spin test of the helicopter’s rotors to nearly 2,500 rpm. Tests show that the solution allows the helicopter to switch to flight mode and take off on 85% of the attempts
“We also know that if the first attempt on Monday doesn’t work, we can try these commands again, with a high probability that subsequent attempts in the days that follow, even if the first doesn’t work,” wrote Aung. “For these reasons we have chosen to follow this path.”
Meanwhile, teams on Earth continue to pursue the backup option to update Ingenuity’s software. The new software has already been uplinked to the Perseverance rover, which could send the code to Ingenuity if needed over the wireless communication link between the rover and the helicopter.
“If our initial approach to the flight doesn’t work, the rover will send the new flight control software to the helicopter,” Aung wrote. “We would then need a few extra days of preparation to load and test the new software on Ingenuity, rerun the rotor tests in this new configuration, and recycle for a first flight attempt.”
Aung compared the test flight attempt to a missile launch.
“We’re doing everything we can to make it a success, but we also know that we may have to scrub and try again,” she wrote. “There is always uncertainty in engineering, but this is what makes working on advanced technology so exciting and rewarding. We must continuously innovate and develop solutions for new challenges. And we can try things that others have only dreamed of. “
“Ingenuity is a technological experiment,” wrote Aung. As such, our plan is to shift the envelope and learn by doing. We take risks that other missions cannot by carefully weighing each step. “
When all works, the carbon fiber rotors will spin nearly 40 times per second to lift the Ingenuity helicopter off the ground. The rotor blades themselves have a mass of just 35 gains, or a weight of just over 1 ounce, and they must spin faster than helicopter rotors on Earth.
“A helicopter plane flies by generating lift,” Aung said. “On Earth it is by pushing air, so the blades push the air and the lift is generated. On Mars, where the atmospheric density is so thin – about 1% compared to here – there are basically fewer molecules to push. So that means we have to compensate … We have to spin so much faster than on Earth. “
The helicopter’s super-light weight, coupled with lightning-fast control algorithms to adjust the craft’s flight 500 times per second, required advanced materials and computing power.
“We just couldn’t do it 15 or 20 years ago,” Aung said.
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