What Flight 50 Means for the Ingenuity Mars Helicopter

JPL’s Ingenuity helicopter is making ready for the fiftieth flight of its 5-flight mission to Mars. Flight 49, which occurred final weekend, was its quickest and highest but—the little helicopter flew 282 meters at an altitude of 16 meters, reaching a high velocity of 6.50 meters per second. Not a nasty efficiency for a tech demo that was speculated to be terminated two years in the past.

From right here, issues are solely going to get tougher for Ingenuity. As the Perseverance rover continues its climb up Jezero crater’s historical river delta, Ingenuity is making an attempt its greatest to scout forward. But, the winding hills and valleys make it tough for the helicopter to speak with the rover, and thru the rover, to its staff again on Earth. And there isn’t a number of time or room to spare, as a result of Ingenuity isn’t allowed to fly too near Perseverance, that means that if the rover ever catches as much as the helicopter, the helicopter might must be left behind for the rover’s personal security. This high-stakes race between the helicopter scout and the science rover will proceed for kilometers.

“Two years in, 10 kilometers flown, and we’re well over an hour now in the skies of Mars.”
—Teddy Tzanetos, NASA

For the Ingenuity staff, this new mode of operation was each a problem and a possibility. This was nothing new for people who’ve managed to maintain this 30-day expertise demo alive and wholesome and productive for years, all from a pair hundred million kilometers away. IEEE Spectrum spoke with Ingenuity Team Lead Teddy Tzanetos at JPL final week about whether or not flying on Mars is ever routine, how they upgraded Ingenuity for its prolonged mission, and what the helicopter’s success means for the way forward for airborne exploration and science on Mars.

IEEE Spectrum: Is 50 flights on Mars a milestone for you of us, or are issues routine sufficient now that you just’re taking a look at it as simply one other flight?

Teddy Tzanetos: It’s massively significant. We’ll come again to the routine query in a second, but it surely’s very significant for all of us. When we hit 10 after which 25 it was huge, however 50 is a reasonably severe quantity now that we’re 10X our preliminary flight depend. Two years in, 10 kilometers flown, and we’re nicely over an hour now within the skies of Mars. So hitting flight 50, it’s a giant factor—we’re in all probability going to arrange a contented hour and have a giant celebration for the staff.

Can you speak about among the new challenges that Ingenuity has been going through because it makes its method up Jezero Crater’s river delta together with the Perseverance rover?

Tzanetos: The core of the problem right here is that the paradigm has modified. When you take a look at the primary 12 months of Ingenuity’s prolonged operations, we had been nonetheless within the Three Forks space, the place the bottom was flat. We might get line of sight from the helicopter to the rover from a whole bunch and a whole bunch of meters away. Our longest hyperlink that we established was 1.2 kilometers—a large distance.

And then we began to understand that the rover was going to enter the river delta in like six months. It’s going to start out climbing up by means of dozens and dozens of meters of elevation change and passing by means of ravines, and that’s going to start out presenting a telecom situation for us. We knew that it couldn’t be enterprise as traditional anymore—if we nonetheless needed to maintain this helicopter mission going, not solely did we have to change the best way we had been working, however we additionally needed to change the helicopter itself.

“We owe it to everyone who worked on Ingenuity and everyone who will continue to work on rotorcraft on Mars to try and get everything out of this little spacecraft that we can.”
—Teddy Tzanetos, NASA

This realization culminated in essentially the most difficult flight software program improve we’ve ever achieved with Ingenuity, which occurred final December. We went into the center of our algorithms and added two new options. One was the power to detect and react to touchdown hazards from the air, which concerned handing over a little bit little bit of autonomy again to Ingenuity, with the power to inform it, “Fly to your terminal waypoint and try and land where we think is good, based off of orbital imagery. But if you have better information from your images than what we humans had here on Earth, and you see a hazard, pick a safer site and land there instead.” So that’s one big change in what’s occurring now. And we want that on the river delta as a result of we’re not flying in a parking zone—in addition to the problem of the elevation change, the terrain is totally different as nicely, with extra, bigger rocks that Ingenuity must keep away from.

The second characteristic that we added was to incorporate details about the terrain to Ingenuity’s navigation filter. When we designed Ingenuity, we assumed we had been solely going to be deployed on the flat terrain of Three Forks. Therefore, any change within the laser altimeter measurement we might belief to be an actual change within the movement of the helicopter, or we might not less than filter that into our altitude information. But that’s not the case. Now, as Ingenuity flies, if the altimeter sees a giant lower in elevation, that might be as a result of the bottom is rising to fulfill us relatively than as a result of we’re shifting down. So since December, we’ve been telling Ingenuity in regards to the elevation profile throughout its supposed flight in order that it is aware of what the bottom is doing beneath it.

Now that each the rover and the helicopter have begun the river delta climb, we’re additionally paying very shut consideration to our telecom hyperlink price range maps. You can think about each hill or rise that might occlude the road of sight between the helicopter antenna and the rover antenna can have a big effect in your telecom hyperlink, and now we have great maps from orbit the place we will choose a possible touchdown level and propagate our radio hyperlink price range calculation throughout that time.

We’re making an attempt to plan these flights as aggressively as we will to ensure that we keep forward of Perseverance. We don’t need to run the chance of getting a state of affairs the place the rover might have to attend for Ingenuity—that’s not a very good factor for anyone. But we additionally need to present worth for the rover by scouting forward, and what we hope to do on Flight 50 is to get some imagery of Belva crater, which is that this stunning large crater to the north of the place Ingenuity at present is. We’re going to get views that the rover staff wouldn’t be capable to present for the science staff, and it’s actually thrilling for us when there are these moments which can be uniquely pushed by Ingenuity’s functionality. We need to go after these, as a result of we need to present that worth whereas she’s nonetheless wholesome. While we nonetheless can. We owe it to everybody who labored on Ingenuity and everybody who will proceed to work on rotorcraft on Mars to try to get all the pieces out of this little spacecraft that we will.

“One of the best hallmarks of technology success is when you don’t realize it, or when it becomes boring. That means the technology is working, and that’s a wonderful feeling.”
—Teddy Tzanetos, NASA

At one level, NASA was very clear that Ingenuity’s mission would come to an finish in order that Perseverance might transfer on to give attention to its major mission. But clearly, Ingenuity remains to be flying, and nonetheless maintaining with the rover. Not solely that, however we’ve heard from a rover driver how priceless it’s to have Ingenuity scouting forward. With that in thoughts, as Ingenuity navigates this difficult terrain, will there be any flexibility if one thing doesn’t go fairly proper, or will Perseverance simply go away the helicopter behind?

Tzanetos: We have to take a look at the large image. The most essential factor at this level is for Perseverance to gather samples and do science. If you take a look at all the pieces that must be achieved throughout the entire rover’s science payloads, each sol [Martian day] is treasured. And the helicopter staff understands that.

We’re doing our greatest to turn out to be extra environment friendly, and I believe that’s a giant win that we don’t rejoice sufficient on the Ingenuity staff internally—how far more environment friendly we’re right now in comparison with the place we had been two years in the past. Earlier, you talked about flying changing into routine. I believe the staff has succeeded in doing that, and I’m extraordinarily pleased with that accomplishment. One of the perfect hallmarks of expertise success is once you don’t understand it, or when it turns into boring. That means the expertise is working, and that’s an exquisite feeling.

There’s what’s referred to as a tactical window that now we have between the downlink of the final sol’s exercise and when we have to uplink exercise for the following sol, which is anyplace from 5 to 10 hours. A sure cadence of actions must happen throughout that window, and we have to cross sure checkpoints to get our information uploaded and radiated by means of the Deep Space Network in time. We’ve labored very, very arduous to attenuate our footprint on that timeline, whereas additionally being reactive in order that we will transfer shortly on any last-minute modifications that the rover staff wants us to accommodate. We must get in, fly, and get out.

Anomalies will occur. That’s simply the character of Mars. But when these moments happen, the helicopter and rover groups again one another up. To be clear, nobody on the helicopter staff needs to trigger a delay for the rover. We all need the rover to meet its mission, get its samples, and get the science achieved. If now we have a severe anomaly, we’ll must take that one sol at a time. We’re going to strive as arduous as we will to ensure we will preserve pushing this little child so far as we will whereas nonetheless conducting the core science mission.

NASA’s Ingenuity Mars Helicopter takes off and lands on this video captured on April 19, 2021, by Mastcam-Z, an imager aboard NASA’s Perseverance Mars rover. This video options solely the moments of takeoff and the touchdown—and never footage of the helicopter hovering for about 30 seconds.NASA/JPL-Caltech/ASU/MSSS

How do you steadiness danger to the helicopter in opposition to exploration and science targets, or making an attempt new issues like pushing Ingenuity’s flight envelope?

Tzanetos: That’s the enjoyable half! There’s no instruction guide. The method we do it’s now we have a telephone name with the core folks on the staff, and everybody simply shares their opinions. The highest precedence for us is getting some good scouting imagery for the scientists and rover drivers—we bounce at these alternatives. If we’re flying by means of a bit of terrain that isn’t significantly fascinating, that’s once we begin wanting on the flight envelope developments, proper? With flight 49, we’re going greater than we ever had earlier than and flying quicker than we ever have earlier than. That’s not a request from the science group or the rover planners; that’s coming from our personal inside staff the place we’re making an attempt to launch functionality piece by piece because the flights go on, as a result of each time we get that win, it’s a win for the pattern restoration helicopters. So there’s that ever-present stress to push more durable, push quicker, push greater. And let’s additionally get some great scouting information alongside the best way once we can.

What have you ever discovered about flying helicopters on Mars from 50 flights, that you’d don’t know about for those who’d been in a position to do exactly 5 flights?

Tzanetos: Tons of issues. Since I simply talked about flying quicker and flying greater, and we’ve now legitimately expanded Ingenuity’s flight envelope. There’s the lifetime argument, which is apparent—this design has lasted for much longer than anybody might have anticipated, even simply by way of elements and workmanship. Each one in all Ingenuity’s practically a thousand solder joints had been soldered by technicians at JPL who’ve essentially the most blessed, exact palms. We’d designed Ingenuity to fly in springtime on Mars, however in the course of the Martian winter, for greater than 200 sols the temperature cycled between 20°C and -90°C and again once more. Eventually, it received so chilly that Ingenuity’s battery would die each evening, the heater would cease operating, and all the pieces would freeze. That was a large curveball that we needed to cope with, however due to the workmanship of these folks, Ingenuity was in a position to survive.

“We now have a stake in the ground to say, ‘Off-the-shelf works, we can trust these things.’”
—Teddy Tzanetos, NASA

Also, mud. We knew that mud would decide on Ingenuity’s photo voltaic panel, however we’ve proven that by means of the method of flying, there’s some form of impact that’s serving to us to maintain our panel clear. It’s tough to place a finger on precisely what it’s—perhaps the vibration of flight, or the downwash of air passing over the photo voltaic panel and into the rotors, or the oncoming air as we transfer ahead. And it wasn’t simply the mud on the panels; we additionally received mud in our actuators. Last 12 months, Ingenuity weathered a giant mud storm, and afterwards once we tried checking our management surfaces, issues didn’t look good. The motor currents had been method too excessive, and we had been left scratching our heads, making an attempt to determine what to do. We didn’t have mud boots across the rotor system just because we had thought, “we’re only going to be operating for 30 days, we don’t need them.”

Our companions at AeroVironment [who worked with JPL on the Mars helicopter design] had one of many swash plate mechanisms mendacity round, so that they spoke to our geologists to determine what sorts of mud particles may need gotten blown into the swash plate on Mars. We despatched them some simulated Mars mud, they usually threw it on the swash plate, after which did an experiment to determine what number of occasions they wanted to cycle it earlier than it began to function correctly. Seven cycles received many of the mud out, so we tried that on Mars, and it labored. So now now we have a brand new device in our device belt: we all know the best way to clear ourselves. That’s big. And we wouldn’t have found out any of these items had we not gone previous 5 flights.

Looking on the Mars pattern return helicopters, how a lot of their design has been made attainable by the truth that Ingenuity has been in a position to fly this lengthy, and reply these questions that you just won’t have even thought to ask?

The complete design. I don’t assume we’d be speaking about pattern restoration helicopters if Ingenuity didn’t fly, interval, and if it hasn’t survived for so long as it has. You have to remember, Ingenuity is a tech demo. These pattern restoration helicopters are an actual a part of the mission now. If Perseverance has an anomaly within the subsequent decade, these helicopters are the backup—they must work. And I’m certain that Ingenuity’s two years of prolonged operations supplied the proof essential to even begin speaking in regards to the pattern restoration helicopters. Otherwise, it will be loopy to assume, “let’s go from tech demo to part of a class B mission within a year.”

That’s wonderful. It should really feel actually good for you of us to have utterly modified what the pattern return mission seems to be like due to how profitable Ingenuity has been.

Absolutely. I personally thought to myself, “Hey, this is great, Ingenuity has been doing a great job, and this will be wonderful data for the next time we send a rotorcraft to Mars.” Which I believed was going to be like ten years later—I believed that Mars pattern return would occur with a rover, after which perhaps after that, we might throw some helicopters on Mars, perhaps a hexacopter with some science payloads on it. Never in my wildest desires did I ever assume, whereas we’re nonetheless flying Ingenuity, that we’d be designing the subsequent helicopter mission primarily based on Ingenuity to go to Mars.

More broadly, how has Ingenuity influenced NASA’s strategy to robotics?

From a robotics perspective, I hope one of many long-lasting impacts of Ingenuity is the adoption of business off-the-shelf expertise into extra NASA missions, and different non-NASA missions into house. This was the primary time we flew a cellular phone processor, not as a result of we cherished the thought about utilizing a component that wasn’t radiation hardened, however as a result of we had been pressured to. We wanted a high-throughput processor, and the one method to do this and be light-weight sufficient was to make use of a cellular phone chip. There was a number of concern about that—we did some preliminary testing, however on condition that we had been a tech demo, which suggests high-risk, excessive reward, we might solely achieve this a lot. And right here we’re, two years later, with this Snapdragon Qualcomm processor that’s been operating for 2 years on the floor of Mars, to not point out all the opposite parts just like the IMU, the digicam, the battery, the photo voltaic panels. I believe that’s one of many unsung victories of Ingenuity. We now have a stake within the floor to say, “Off-the-shelf works, we can trust these things.” And we will make a stronger argument for the following mission to actually allow your engineers and your scientists to have far more expertise on board than anything we’ve despatched into house.

Ingenuity will try Flight 50 any time now, with the aim of touring 300 meters to the opposite aspect of a ridge. The touchdown website might make it tough to know whether or not the flight was profitable till Perseverance catches up a bit, however we hope to listen to the excellent news inside the subsequent few days.