Blade Strike on Touchdown Ends Mars Helicopter’s Epic Journey

The Ingenuity Mars Helicopter made its 72nd and last flight on 18 January. “Whereas the helicopter stays upright and in communication with floor controllers,” NASA’s Jet Propulsion Lab stated
in a press launch this afternoon, “imagery of its Jan. 18 flight despatched to Earth this week signifies a number of of its rotor blades sustained injury throughout touchdown, and it’s now not able to 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 “tough touchdown,” and this isn’t the type of injury that may permit 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 offer 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 staff 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. Information exhibits that, as deliberate, the helicopter achieved a most altitude of 40 toes (12 meters) and hovered for 4.5 seconds earlier than beginning its descent at a velocity of three.3 toes per second (1 meter per second).

Nevertheless, about 3 toes (1 meter) above the floor, Ingenuity misplaced contact with the rover, which serves as a communications relay for the rotorcraft. The next day, communications had been reestablished and extra details about the flight was relayed to floor controllers at NASA JPL. Imagery revealing injury 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.

Whereas 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 among the hardest terrain we’ve ever needed to navigate over,” stated
Teddy Tzanetos, Ingenuity Challenge Supervisor at NASA JPL, through the NASA press convention. “It’s very featureless—bland, sandy terrain. And that’s why we consider that in Flight 71, we had an emergency touchdown. She was flying over the floor and was realizing that there weren’t too many rocks to take a look at or options to navigate from, and that’s why Ingenuity referred to as an emergency touchdown on her personal.”

Ingenuity makes use of a downward-pointing VGA digital camera working 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 method is used for drones (and different robots) on Earth too, and it’s very dependable, so long as you may have sufficient options to trace. The place it begins to go improper is when your digital camera is taking a look at issues which can be featureless, which is why client drones will typically warn you about surprising conduct 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 on the lookout for distinctive options like rocks, however flying over a featureless expanse of sand triggered severe issues, as Ingenuity’s Chief Pilot Emeritus Håvard Grip defined to us throughout at the moment’s press convention:

The way in which a system like this works is by trying 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 improper sorts of options, and that’s when issues can get off monitor.

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

After the Flight 71 emergency touchdown, the staff determined to attempt a “pop-up” flight subsequent: it was speculated 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 methods. As Ingenuity was descending, simply earlier than touchdown, there was a lack of communications with the helicopter. “We’ve motive to consider that it was dealing with the identical featureless sandy terrain challenges [as in the previous flight],” stated Tzanetos. “And due to the navigation challenges, we had a rotor strike with the floor that will have resulted in an influence brownout which triggered the communications loss.” Grip describes what he thinks occurred in additional element:

A few of that is hypothesis due to the sparse telemetry that we’ve got, 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, after we’re closing in on the bottom, the helicopter comparatively shortly begins to assume that it’s transferring horizontally away from the touchdown goal. It’s doubtless that it made an aggressive maneuver to attempt to appropriate that proper upon touchdown. And that will have accounted for a sideways movement and tilt of the helicopter that might have led to both placing 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 placing the blade, we don’t know these particulars but. We could by no means know. However we’re making an attempt as onerous as we are able to with the information that we’ve got to determine these particulars.

When the Ingenuity staff tried reestablishing contact with the helicopter the subsequent
sol, “she was proper there the place we anticipated her to be,” Tzanetos stated. “Photo voltaic panel currents had been trying good, which indicated that she was upright.” In actual fact, every part was “inexperienced throughout the board.” That’s, till the staff began trying by means of the pictures from Ingenuity’s navigation digital camera, and noticed the shadow of the broken decrease blade. Even when that’s the one injury to Ingenuity, the entire rotor system is now each unbalanced and producing considerably much less elevate, and additional flights will probably be unimaginable.

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 the moment may very well be the final day, at the moment may very well be the final day. So there was an preliminary second, clearly, of unhappiness, seeing that photograph come down and pop on display, which provides us certainty of what occurred. However that’s in a short time changed with happiness and pleasure and a sense of celebration for what we’ve pulled off. Um, it’s actually exceptional the journey that she’s been on and value celebrating each single a kind of sols. Round 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 tip of her mission. —Teddy Tzanetos

The Ingenuity staff is guessing that there’s injury to greater than one of many helicopter’s blades; the blades spin quick sufficient that if one hit the floor, others doubtless did too. The plan is to try to slowly spin the blades to deliver others into view to attempt to accumulate extra info. It sounds unlikely that NASA will divert the Perseverance rover to offer 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 doubtless too distant for 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 complete motive for existence was to push the boundaries of what’s attainable. 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 may:

General, the best way that Ingenuity has navigated utilizing options of terrain has been extremely profitable. We didn’t design this method to deal with this type of terrain, however nonetheless it’s form of been invincible till this second the place we flew on this fully bland terrain the place you simply don’t have anything to essentially maintain on to. So there are some classes in that for us: we now know that that specific type 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 geared up with. After which there are answers like having the next decision digital camera, which might have doubtless helped mitigate this example. But it surely’s all a part of this tech demo, the place we geared up this helicopter to do at most 5 flights in a pre-scouted space and it’s gone on to take action far more than that. And we simply labored all of it the best way 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 necessary contribution has been exhibiting that it’s not simply attainable,
however sensible and helpful to have rotorcraft on Mars. “I don’t assume we’d be speaking about pattern restoration helicopters if Ingenuity didn’t fly, interval, and if it hadn’t survived for so long as it has,” Teddy Tzanetos advised us after Ingenuity’s fiftieth flight. And it’s not simply the pattern return mission: JPL can also be creating a a lot bigger Mars Science Helicopter, which can owe its existence to Ingenuity’s success.

Practically three years on Mars. 128 minutes and 11 miles of flight within the Martian skies. “I stay up for the day that certainly one of our astronauts brings house Ingenuity and we are able to all go to it within the Smithsonian,” stated
Director of JPL Laurie Leshin on the finish of at the moment’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 staff members, and so they’re effectively price re-reading at the moment. Thanks, Ingenuity. You probably did effectively.

What Flight 50 Means for the Ingenuity Mars Helicopter

Workforce lead Teddy Tzanetos on the helicopter’s milestone aerial mission

Mars Helicopter Is A lot Extra Than a Tech Demo

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