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Tag: Perseverance rover

  • NASA’s Perseverance doesn’t need GNSS to find itself on Mars

    NASA’s Perseverance doesn’t need GNSS to find itself on Mars

    News from NASA’s Jet Propulsion Laboratory

    A new technology called Mars Global Localization lets Perseverance determine precisely where it is, without human help.

    Imagine you’re all alone, driving along in a rocky, unforgiving desert with no roads, no map, no GPS, and no more than one phone call a day for someone to inform you exactly where you are. That’s what NASA’s Perseverance rover has been experiencing since landing on Mars five years ago. Though it carries time-tested tools for determining its general location, the rover has needed operators on Earth to tell it precisely where it is — until now.

    A new technology developed at NASA’s Jet Propulsion Laboratory in Southern California enables Perseverance to figure out its whereabouts without calling humans for help. Dubbed Mars Global Localization, the technology features an algorithm that rapidly compares panoramic images from the rover’s navigation cameras with onboard orbital terrain maps.

    Running on a powerful processor that Perseverance originally used to communicate with the Ingenuity Mars Helicopter, the algorithm takes about two minutes to pinpoint the rover’s location within some 10 inches (25 centimeters). Mars Global Localization was first used successfully in regular mission operations on Feb. 2, then again Feb. 16.

    “This is kind of like giving the rover GPS. Now it can determine its own location on Mars,” said JPL’s Vandi Verma, chief engineer of robotics operations for the mission. “It means the rover will be able to drive for much longer distances autonomously, so we’ll explore more of the planet and get more science. And it could be used by almost any other rover traveling fast and far.”

    This panorama from Perseverance is composed of five stereo pairs of navigation camera images that the rover matched to orbital imagery in order to pinpoint its position on Feb. 2, 2026, using a technology called Mars Global Localization. (Credit: NASA/JPL-Caltech)
    This panorama from Perseverance is composed of five stereo pairs of navigation camera images that the rover matched to orbital imagery in order to pinpoint its position on Feb. 2, 2026, using a technology called Mars Global Localization. (Credit: NASA/JPL-Caltech)

    The upgrade is especially valuable given how well Perseverance’s auto-navigation self-driving system has been working. Enabling the rover to re-plan its path around obstacles en route to a preestablished destination, AutoNav has proved so capable that the distance Perseverance can drive without instructions from Earth is largely limited by the rover’s uncertainty about its whereabouts. Now that it can stop and determine its exact location, Perseverance can be commanded to drive to potentially unlimited distances without calling home.

    Implementation of Mars Global Localization comes on the heels of another innovation from the Perseverance team: the first use of generative artificial intelligence to help plan a drive route by selecting waypoints for the rover, which are normally chosen by human rover operators. Both technologies enable Perseverance to travel farther and faster while minimizing team workload.

    Beyond visual odometry

    Unlike on Earth, there is no network of GPS satellites in deep space to locate spacecraft on planetary surfaces. So missions — whether robotic or crewed — must come up with other ways to determine their location.

    The Mars Global Localization algorithm runs on a fast commercial processor in the Helicopter Base Station — the upper, gold-colored box that was integrated into NASA’s Perseverance rover in a clean room. Perseverance used the base station to communicate with the now-retired Ingenuity Mars Helicopter. (Credit: NASA/JPL-Caltech)
    The Mars Global Localization algorithm runs on a fast commercial processor in the Helicopter Base Station — the upper, gold-colored box that was integrated into NASA’s Perseverance rover in a clean room. Perseverance used the base station to communicate with the now-retired Ingenuity Mars Helicopter. (Credit: NASA/JPL-Caltech)

     As with NASA’s previous Mars rovers, Perseverance tracks its position using what’s called visual odometry, analyzing geologic features in camera images taken every few feet while accounting for wheel slippage. But as tiny errors in the process add up over the course of each drive, the rover becomes increasingly unsure about its exact location. On long drives, the rover’s sense of its position can be off by more than 100 feet (up to 35 meters). Believing it may be too close to hazardous terrain, Perseverance may prematurely end its drive and wait for instructions from Earth.

    “Humans have to tell it, ‘You’re not lost, you’re safe. Keep going,’” Verma said. “We knew if we addressed this problem, the rover could travel much farther every day.”

    After each drive comes to a halt, the rover sends a 360-degree panorama to Earth, where mapping experts match the imagery with shots from NASA’s Mars Reconnaissance Orbiter (MRO). The team then sends the rover its location and instructions for its next drive. That process can take a day or more, but with Mars Global Localization, the rover is able to compare the images itself, determine its location, and roll ahead on its preplanned route.

    “We’ve given the rover a new ability,” said Jeremy Nash, a JPL robotics engineer who led the team working on the project under Verma. “This has been an open problem in robotics research for decades, and it’s been super exciting to deploy this solution in space for the first time.”

    The small team began working in 2023, testing the accuracy of the algorithm they’d developed using data from 264 previous rover stops. The algorithm compared rover panoramic photos to MRO imagery and correctly pinpointed the rover’s location for every single stop.

    How Ingenuity helped

    Key to Mars Global Localization is the rover’s Helicopter Base Station (HBS), which Perseverance used to communicate with the now-retired Ingenuity Mars Helicopter. Equipped with a commercial processor that powered many consumer smartphones in the mid-2010s, the HBS runs more than 100 times faster than the rover’s two main computers, which, built to survive the radiation-heavy Martian environment, are based on hardware introduced in 1997.

    As a technology demonstration designed to test capabilities, the Ingenuity mission was able to risk employing more powerful commercial chips in the HBS and the helicopter even though they hadn’t been proven in space. It paid off: Expected to fly no more than five times, the rotorcraft completed 72 flights.

    The power of the HBS processor inspired Verma to look for ways the Perseverance mission might harness it. “It’s almost like a gift. Ingenuity blazed the trail, proving we could use commercial processors on Mars,” Verma said.

    Tapping into the HBS computer has had its challenges. To address reliability, the team developed a “sanity check”: The algorithm runs on the HBS multiple times before one of the rover’s main computers checks to ensure the results match. During testing, the team repeatedly found the rover’s position was off by 1 millimeter. They discovered damage to about 25 bits — a minuscule fraction of the processor’s 1 gigabyte of memory — and developed a solution to isolate those bits while the algorithm runs.

    Alongside the broader Mars Global Localization process, the team’s sanity check and memory solutions are expected to find new uses as faster commercial processors are employed in future missions. In the meantime, the team has already turned their sights to the Moon, where difficult lighting conditions and long, cold lunar nights make knowing exactly where spacecraft are located all the more critical.

    More about Perseverance

    NASA’s Jet Propulsion Laboratory, which is managed for the agency by Caltech, built and manages operations of the Perseverance rover on behalf of NASA’s Science Mission Directorate in Washington, as part of NASA’s Mars Exploration Program portfolio. Learn more about Perseverance.

  • Contrasting the use of drones on Mars and in Afghanistan

    Contrasting the use of drones on Mars and in Afghanistan

    NASA and the European Space Agency (ESA) have been cooking up a way to get some of Mars back to Earth, so that samples can be analyzed in detail — just like the rocks the astronauts brought back during the Apollo missions, which gave us a deeper understanding of our Moon.

    The Perseverance rover already on Mars has been seeking promising areas to investigate that might provide evidence of ancient past life, with the help of the Ingenuity helicopter drone. Recently, the two worked together to drive the rover to an old river delta, expected to be a prime location where such samples could be found.

    The rover has been drilling and saving rock and dirt samples in onboard storage tubes. The difficulty is that getting them back to Earth requires another major undertaking.

    Returning the Samples

    Termed the “Sample Return Mission,” the two space agencies have been discussing for months how best to bring the samples back, and have now refined an approach. Given that Perseverance has been so good at the job it was given, the NASA/ESA team has decided that the rover should be used for the return mission in 2030 when things would be in operation on Mars. (We’re not sure if the warranty sticker on Perseverance will still be valid in 2030, but if past performance is an indication, all the rovers have significantly outlived their initial design lives.)

    Its partner Ingenuity has graduated from proving it can fly in the thin Martian air to actually scouting routes for the large rover. Because Ingenuity has proven reliable and capable of traveling significant distances, NASA and ESA have decided that two new helicopter drones will become part of the return mission. They will be based on the successful Ingenuity design, but will be fitted with wheels, one on each of the four landing legs, to enable movement on the ground.

    They will also be fitted with a device which is capable of picking up and carrying a sample tube. Since the prototype drone helicopter was designed to be as light as possible, this infers  a substantial increase in lift capacity will be required. The original mission included a sample-collection rover, but this task will now be assigned to Perseverance, with the two sample-carrying helicopters acting as backup, if needed.

    An earlier concept had the rover dropping sample canisters behind it as it progressed around the surface for subsequent pick up. This concept appears to have been shelved for the moment. Keeping the canisters onboard the rover throughout perhaps simplifies transfer to the return lander.

    NASA Return Sample concept illustration includes wheeled helicopters. (Image: NASA)
    This NASA return sample concept illustration includes wheeled helicopters. (Image: NASA/JPL-Caltech)

    The Mars Ascent Vehicle would then carry the samples into orbit, to a waiting Earth Return Obiter, where the samples would be transferred to a return system for onward transit and atmospheric re-entry to Earth. Some of these details are a little sketchy, but there sure are a lot of moving (autonomous, robotic?) parts. This, of course, means a lot of opportunities for something to go wrong. No doubt continuing refinement of the mission will reduce the risks. The Jet Propulsion Lab (JPL) and AeroVironment designed and built Ingenuity — they may face some challenges developing the successor helicopter drones.

    Meanwhile, Here on Earth…

    Drones led the news Aug. 1, when President Biden announced the killing of Ayman al-Zawahiri in Kabul, Afghanistan. Al-Zawahiri topped the U.S. 9/11 wanted list, and his removal was all about the offensive use of drones. Presumably fired from a General Atomics Reaper variant drone at quite some altitude, two Hellfire AGM-114R9X “knife bomb”missiles took out al-Zawahiri as he stood alone on the balcony of a home in Kabul.

    This means that video/infrared from high altitude was sufficiently clear to determine that the man was alone on the balcony, presumably confirming information on the ground that his family was elsewhere. So long-distance, high-level authorization was then granted to fire on him in a foreign country now run by the Taliban.

    Suspected damaged al-Zawahiri house in Kabul (Photo: Secunder Kermani/BBC News)
    Suspected damage at the al-Zawahiri house in Kabul. (Photo: Secunder Kermani/BBC News)

    To minimize inadvertent casualties, the Hellfire R9X missile was used, which lacks explosive armaments. The weapon is a nasty piece of work, weighing ~100 lb with an inert payload, and fitted with six long knives that deploy before impact. This missile has previously been used in perhaps 11 other instances to take out terrorist individuals and minimize collateral damage.

    Bladed R9X missle lacks warhead (Image: Newsy/Bellingcat)
    Bladed R9X missile lacks a warhead (Image: Newsy/Bellingcat)

    This is another instance of how the U.S. use of military drones has become less devastating, but is still very deadly to the specific target.

    To Sum Up

    We’ve taken a quick glimpse at how NASA and ESA are planning more drones for the surface of Mars, and a much more aggressive use of drones here on Earth.

  • ION hosts webinar on navigation of Mars Perseverance rover

    ION hosts webinar on navigation of Mars Perseverance rover

    Image: IONThe Institute of Navigation will host the Navigation of the Mars 2020 Perseverance Rover from Earth to Jezero Crater webinar on Tuesday, March 23, at 1:30 p.m. EDT.

    The webinar will be presented by Gerhard Kruizinga, navigation engineer, Mars 2020 Navigation Team chief, NASA’s Jet Propulsion Laboratory, and moderated by Frank van Diggelen, ION president.

    “We are honored to have the Navigation team chief of this historic mission, Gerhard Kruizinga, present his first-hand account of getting NASA’s Mars 2020 Perseverance Rover from the launch pad to a safe landing on Mars,” van Diggelen said.

    The precision landing required very high-precision interplanetary navigation and accommodation of entry guidance target requirements, planetary protection requirements and propellant allocation for trajectory correction maneuvers.

    The main navigation objective was to predict the trajectory accuracy at atmospheric entry, such that the entry descent and landing system requirements were satisfied for a safe landing. This presentation discusses the planning to meet all navigation requirements and the actual navigation performance during cruise and landing.

    Register here for the webinar.