The Ingenuity Mars Helicopter has been doing an amazing job flying on Mars. Over the last several weeks it has far surpassed its original goal of proving that flight on Mars was simply possible, and is now showing how such flights are not only practical but also useful.
To that end, NASA has decided that the little helicopter deserves to not freeze to death quite so soon, and the agency has extended its mission for at least another month, giving it the opportunity to scout a new landing site to keep up with Perseverance as the rover starts its own science mission.
Some quick context: the Mars Helicopter mission was originally scheduled to last 30 days, and we’re currently a few weeks into that. The helicopter has flown successfully four times; the most recent flight was on April 30, and was a 266 meter round-trip at 5 meters altitude that took 117 seconds. Everything has worked nearly flawlessly, with (as far as we know) the only hiccup being a minor software bug that has a small chance of preventing the helicopter from entering flight mode. This bug has kicked in once, but JPL just tried doing the flight again, and then everything was fine.
In a press conference last week, NASA characterized Ingenuity’s technical performance as “exceeding all expectations,” and the helicopter met all of its technical goals (and then some) earlier than anyone expected. Originally, that wouldn’t have made a difference, and Perseverance would have driven off and left Ingenuity behind no matter how well it was performing. But some things have changed, allowing Ingenuity to transition from a tech demo into an extended operational demo, as Jennifer Trosper, Perseverance deputy project manager, explained:
“We had not originally planned to do this operational demo with the helicopter, but two things have happened that have enabled us to do it. The first thing is that originally, we thought that we’d be driving away from the location that we landed at, but the [Perseverance] science team is actually really interested in getting initial samples from this region that we’re in right now. Another thing that happened is that the helicopter is operating in a fantastic way. The communications link is overperforming, and even if we move farther away, we believe that the rover and the helicopter will still have strong communications, and we’ll be able to continue the operational demo.”
The communications link was one of the original reasons why Perseverance’s mission was going to be capped at 30 days. It’s a little bit counter-intuitive, but it turns out that the helicopter simply cannot keep up with the rover, which Ingenuity relies on for communication with Earth. Ingenuity is obviously faster in flight, but once you factor in recharge time, if the rover is driving a substantial distance, the helicopter would not be able to stay within communications range.
And there’s another issue with the communications link: as a tech demo, Ingenuity’s communication system wasn’t tested to make sure that it can’t be disrupted by electronic interference generated by other bits and pieces of the Perseverance rover. Consequently, Ingenuity’s 30-day mission was planned such that when the helicopter was in the air, Perseverance was perfectly stationary. This is why we don’t have video where Perseverance pans its cameras to follow the helicopter—using those actuators might have disrupted the communications link.
Going forward, Perseverance will be the priority, not Ingenuity. The helicopter will have to do its best to stay in contact with the rover as it starts focusing on its own science mission. Ingenuity will have to stay in range (within a kilometer or so) and communicate when it can, even if the rover is busy doing other stuff. This extended mission will initially last 30 more days, and if it turns out that Ingenuity can’t do what it needs to do without needing more from Perseverance, well, that’ll be the end of the Mars helicopter mission. Even best case, it sounds like we won’t be getting any more pictures of Ingenuity in flight, since planning that kind of stuff took up a lot of the rover’s time.
With all that in mind, here’s what NASA says we should be expecting:
“With short drives expected for Perseverance in the near term, Ingenuity may execute flights that land near the rover’s current location or its next anticipated parking spot. The helicopter can use these opportunities to perform aerial observations of rover science targets, potential rover routes, and inaccessible features while also capturing stereo images for digital elevation maps. The lessons learned from these efforts will provide significant benefit to future mission planners. These scouting flights are a bonus and not a requirement for Perseverance to complete its science mission.
The cadence of flights during Ingenuity’s operations demonstration phase will slow from once every few days to about once every two or three weeks, and the forays will be scheduled to avoid interfering with Perseverance’s science operations. The team will assess flight operations after 30 sols and will complete flight operations no later than the end of August.”
Specifically, Ingenuity spent its recent Flight 4 scouting for a new airfield to land at, and Flight 5 will be the first flight of this new operations phase, where it’ll attempt to land at this new airfield, a place it’s never touched down before about 60m south of its current position on Mars. NASA expects that there might be one or two flights after this, but nobody’s quite sure how it’s going to go, and NASA wasn’t willing to speculate about what’ll happen longer term.
It’s important to remember that all of this is happening in the context of Ingenuity being a 30 day tech demo. The hardware on the helicopter was designed with that length of time in mind, and not a multi-month mission. NASA said during their press conference that the landing gear is probably good for at least 100 landings, and the solar panel and sun angle will be able to meet energy requirements for at least a few months. The expectation is that with enough day/night thermal cycles, a solder joint will snap, rendering Ingenuity inoperable in some way. Nobody knows when that’ll happen, but again, this is a piece of hardware designed to function for 30 days, and despite JPL’s legacy of ridiculously long-loved robotic explorers, we should adjust our expectations accordingly. MiMi Aung, Mars Helicopter Project Manager, has it exactly right when she says that “we will be celebrating each day that Ingenuity survives and operates beyond that original window.” We’re just glad that there will be more to celebrate going forward.
Source: IEEE Spectrum