Blade Strike on Landing Ends Mars Helicopter’s Epic Journey

The Ingenuity Mars Helicopter made its 72nd and closing flight on 18 January. “While the helicopter remains upright and in communication with ground controllers,” NASA’s Jet Propulsion Lab mentioned
in a press launch this afternoon, “imagery of its Jan. 18 flight sent to Earth this week indicates one or more of its rotor blades sustained damage during landing, and it is no longer capable of flight.” That’s what you’re seeing within the image above: the shadow of a damaged tip of one of many helicopter’s 4 two-foot lengthy carbon fiber rotor blades. NASA is assuming that not less than one blade struck the Martian floor throughout a “rough landing,” and this isn’t the form of harm that may enable the helicopter to get again into the air. Ingenuity’s mission is over.

The Perseverance rover took this image of Ingenuity on on Aug. 2, 2023, simply earlier than flight 54.NASA/JPL-Caltech/ASU/MSSS

NASA held a press convention earlier this night to present as a lot info as they’ll about precisely what occurred to Ingenuity, and what comes subsequent. First, right here’s a abstract
from the press launch:

Ingenuity’s crew deliberate for the helicopter to make a brief vertical flight on Jan. 18 to find out its location after executing an emergency touchdown on its earlier flight. Data exhibits that, as deliberate, the helicopter achieved a most altitude of 40 ft (12 meters) and hovered for 4.5 seconds earlier than beginning its descent at a velocity of three.3 ft per second (1 meter per second).

However, about 3 ft (1 meter) above the floor, Ingenuity misplaced contact with the rover, which serves as a communications relay for the rotorcraft. The following day, communications had been reestablished and extra details about the flight was relayed to floor controllers at NASA JPL. Imagery revealing harm to the rotor blade arrived a number of days later. The reason for the communications dropout and the helicopter’s orientation at time of landing are nonetheless being investigated.

While NASA doesn’t know for certain what occurred, they do have some concepts primarily based on the reason for the emergency touchdown through the earlier flight, Flight 71. “[This location] is some of the hardest terrain we’ve ever had to navigate over,” mentioned
Teddy Tzanetos, Ingenuity Project Manager at NASA JPL, through the NASA press convention. “It’s very featureless—bland, sandy terrain. And that’s why we believe that during Flight 71, we had an emergency landing. She was flying over the surface and was realizing that there weren’t too many rocks to look at or features to navigate from, and that’s why Ingenuity called an emergency landing on her own.”

Ingenuity makes use of a downward-pointing VGA digicam operating at 30hz for monocular function monitoring, and compares the obvious movement of distinct options between frames to find out its movement over the bottom. This optical circulate approach is used for drones (and different robots) on Earth too, and it’s very dependable, so long as you’ve gotten sufficient options to trace. Where it begins to go flawed is when your digicam is issues which can be featureless, which is why shopper drones will typically warn you about sudden habits when flying over water, and why robotics labs typically have weird carpets and wallpaper: the extra options, the higher. On Mars, Ingenuity has been reliably navigating by searching for distinctive options like rocks, however flying over a featureless expanse of sand brought about critical issues, as Ingenuity’s Chief Pilot Emeritus Håvard Grip defined to us throughout at present’s press convention:

The approach a system like this works is by wanting on the consensus of [the features] it sees, after which throwing out the issues that don’t actually agree with the consensus. The hazard is once you run out of options, once you don’t have very many options to navigate on, and also you’re probably not in a position to set up what that consensus is and you find yourself monitoring the flawed sorts of options, and that’s when issues can get off observe.

This view from Ingenuity’s navigation digicam throughout flight 70 (on December 22) exhibits areas of practically featureless terrain that might trigger issues throughout flights 71 and 72.NASA/JPL-Caltech

After the Flight 71 emergency touchdown, the crew determined to strive a “pop-up” flight subsequent: it was presupposed to be about 30 seconds within the air, simply straight as much as 12 meters after which straight down as a check-out of the helicopter’s techniques. As Ingenuity was descending, simply earlier than touchdown, there was a lack of communications with the helicopter. “We have reason to believe that it was facing the same featureless sandy terrain challenges [as in the previous flight],” mentioned Tzanetos. “And because of the navigation challenges, we had a rotor strike with the surface that would have resulted in a power brownout which caused the communications loss.” Grip describes what he thinks occurred in additional element:

Some of that is hypothesis due to the sparse telemetry that we now have, however what we see within the telemetry is that coming down in the direction of the final a part of the flight, on the sand, once we’re closing in on the bottom, the helicopter comparatively rapidly begins to assume that it’s transferring horizontally away from the touchdown goal. It’s probably that it made an aggressive maneuver to attempt to appropriate that proper upon touchdown. And that might have accounted for a sideways movement and tilt of the helicopter that would have led to both putting the blade to the bottom after which dropping energy, or making a maneuver that was aggressive sufficient to lose energy earlier than touching down and putting the blade, we don’t know these particulars but. We might by no means know. But we’re making an attempt as exhausting as we are able to with the info that we now have to determine these particulars.

When the Ingenuity crew tried reestablishing contact with the helicopter the subsequent
sol, “she was right there where we expected her to be,” Tzanetos mentioned. “Solar panel currents were looking good, which indicated that she was upright.” In reality, the whole lot was “green across the board.” That is, till the crew began wanting by the pictures from Ingenuity’s navigation digicam, and noticed the shadow of the broken decrease blade. Even if that’s the one harm to Ingenuity, the entire rotor system is now each unbalanced and producing considerably much less carry, and additional flights might be inconceivable.

A closeup of the shadow of the broken blade tip.NASA/JPL-Caltech

There’s at all times that piece behind your head that’s preparing each downlink—at present may very well be the final day, at present may very well be the final day. So there was an preliminary second, clearly, of unhappiness, seeing that picture come down and pop on display screen, which supplies us certainty of what occurred. But that’s in a short time changed with happiness and satisfaction and a sense of celebration for what we’ve pulled off. Um, it’s actually exceptional the journey that she’s been on and price celebrating each single a kind of sols. Around 9pm tonight Pacific time will mark 1000
sols that Ingenuity has been on the floor since her deployment from the Perseverance rover. So she picked a really becoming time to come back to the top of her mission. —Teddy Tzanetos

The Ingenuity crew is guessing that there’s harm to greater than one of many helicopter’s blades; the blades spin quick sufficient that if one hit the floor, others probably did too. The plan is to aim to slowly spin the blades to carry others into view to try to accumulate extra info. It sounds unlikely that NASA will divert the Perseverance rover to present Ingenuity a more in-depth look; whereas persevering with on its honest mission the rover will come between 200 and 300 meters of Ingenuity and can attempt to take some footage, however that’s probably too distant for an excellent high quality picture.

Perseverance watches Ingenuity take off on flight 47 on March 14, 2023.NASA/JPL-Caltech/ASU/MSSS

As a tech demo, Ingenuity’s total motive for existence was to push the boundaries of what’s doable. And as Grip explains, even in its final flight, the little helicopter was doing precisely that, going above and past and making an attempt newer and riskier issues till it received so far as it probably might:

Overall, the way in which that Ingenuity has navigated utilizing options of terrain has been extremely profitable. We didn’t design this method to deal with this sort of terrain, however nonetheless it’s type of been invincible till this second the place we flew on this fully bland terrain the place you simply don’t have anything to actually maintain on to. So there are some classes in that for us: we now know that that individual form of terrain is usually a entice for a system like this. Backing up when encountering this featureless terrain is a performance {that a} future helicopter may very well be outfitted with. And then there are answers like having the next decision digicam, which might have probably helped mitigate this case. But it’s all a part of this tech demo, the place we outfitted this helicopter to do at most 5 flights in a pre-scouted space and it’s gone on to take action rather more than that. And we simply labored all of it the way in which as much as the road, after which simply tipped it proper over the road to the place it couldn’t deal with it anymore.

Arguably, Ingenuity’s most essential contribution has been displaying that it’s not simply doable,
however sensible and invaluable to have rotorcraft on Mars. “I don’t think we’d be talking about sample recovery helicopters if Ingenuity didn’t fly, period, and if it hadn’t survived for as long as it has,” Teddy Tzanetos advised us after Ingenuity’s fiftieth flight. And it’s not simply the pattern return mission: JPL can be growing a a lot bigger Mars Science Helicopter, which is able to owe its existence to Ingenuity’s success.

Nearly three years on Mars. 128 minutes and 11 miles of flight within the Martian skies. “I look forward to the day that one of our astronauts brings home Ingenuity and we can all visit it in the Smithsonian,” mentioned
Director of JPL Laurie Leshin on the finish of at present’s press convention.

I’ll be first in line.

We’ve written extensively about Ingenuity, together with in-depth interviews with each helicopter and rover crew members, they usually’re effectively value re-reading at present. Thanks, Ingenuity. You did effectively.

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A Mars rover driver explains simply how a lot of a distinction the little helicopter scout is making to Mars exploration