That NASA’s Mars rover, Perseverance, achieved a remarkable feat by navigating through a field of boulders that was more than 1,700 feet wide, and it did so in about one-third of the time it would have taken previous Mars rovers. This challenging terrain was called “Snowdrift Peak.”What makes this achievement even more impressive is that Perseverance managed the detailed navigation of this rocky field on its own, thanks to a self-driving system called AutoNav. AutoNav is designed to autonomously guide the rover, allowing it to move efficiently between different scientific points of interest on Mars.
Since its landing on Mars in February 2021, Perseverance has been setting speed records for rovers on the planet. The success of AutoNav in helping Perseverance navigate tricky terrains like Snowdrift Peak was documented in a paper published in the journal Science Robotics in July.
The passage also mentions Tyler Del Sesto, who has been working on the software for Perseverance’s AutoNav for seven years. Initially, he thought some of the obstacles presented to Perseverance’s Earthly twin, OPTIMISM, during testing at NASA’s Jet Propulsion Laboratory were too challenging. However, his perspective changed after witnessing Perseverance’s successful navigation through Snowdrift Peak, highlighting the capabilities of the rover’s autonomous systems.
Tyler Del Sesto, who has been involved in developing the software for NASA’s Perseverance rover’s AutoNav system for seven years, reflects on his previous perceptions and experiences.Tyler initially had doubts about the challenges presented to Perseverance’s Earthly twin, OPTIMISM, during testing in the Mars Yard at NASA’s Jet Propulsion Laboratory. He felt that some of these obstacles were overly difficult or demanding for the rover. However, his perspective changed after witnessing the rover’s performance in navigating Snowdrift Peak.
Snowdrift Peak turned out to be a particularly challenging terrain for Perseverance. It was densely populated with large rocks, making it much more rugged and complex than any terrain Perseverance had encountered before on Mars. Del Sesto, who serves as the deputy rover planner lead for Perseverance at JPL in Southern California, describes how they faced a dilemma. They didn’t want to go around this challenging terrain because it would have consumed several weeks of rover travel time.
On June 26, NASA’s Perseverance rover successfully entered the eastern edge of Snowdrift Peak on Mars. The journey, which included two stops for boulders that the science team wanted to inspect, covered a straight-line route of 1,706 feet (520 meters). However, by the time the rover exited the western edge of the boulder field on July 31, it had traveled an impressive distance of 2,490 feet (759 meters). This extra distance was due to the rover’s AutoNav feature, which allowed it to maneuver around rocks that were not visible in the orbiter images used to plan its route.
According to Del Sesto, a member of the mission team, the traverse through Snowdrift Peak only took six autonomous drive sols (Martian days), which is significantly faster than it would have taken Curiosity rover. This impressive feat was made possible by the knowledge and experience gained from previous missions such as Sojourner, Spirit, Opportunity, and Curiosity.
Escaping the Martian Rocks.
The evolution of navigation technology on Mars rovers over the years. Since the first Mars rover in 1997, a form of silicon-based navigation system has been in use. The initial rover, Sojourner, was the size of a microwave oven and had to stop every 5.1 inches (13 centimeters) to allow its computer to assess its surroundings before continuing. This frequent pausing was necessary because the rover’s navigation system required regular updates.The next generation of Mars rovers, Spirit and Opportunity, which arrived in 2004, were larger (about the size of a golf cart) and could travel longer distances, up to 1.6 feet (0.5 meters), before needing to stop for navigation checks. However, they still had to pause periodically to determine their next moves.
In contrast, Curiosity, which landed on Mars in 2012, received a software upgrade to enhance its navigation capabilities. But Perseverance, the latest rover to land on Mars in 2021, brings several advantages to the table. It boasts faster cameras that can capture images rapidly enough to process its route in real-time. Additionally, Perseverance is equipped with an extra computer solely dedicated to image processing. This eliminates the need for frequent pauses during its journey, as it can make quicker, more informed decisions about its path without interruption.
Vandi Verma, the lead author of the paper and the mission’s chief engineer for robotic operations at NASA’s Jet Propulsion Laboratory (JPL), discusses the unique capabilities of the Perseverance rover.Perseverance is distinguished by the fact that it has two computer brains working in tandem, allowing it to make real-time decisions autonomously. This means that the rover can analyze its surroundings and make on-the-spot decisions without needing constant human input or review.
The autonomous capability of Perseverance has enabled it to achieve significant milestones in Mars exploration, such as covering impressive distances in a single day, including a record-setting single-day drive distance of 1140.7 feet (347.7 meters). Additionally, it holds the record for the longest drive without the need for human review, covering 2296.2 feet (699.9 meters).
These accomplishments were achieved when Perseverance was navigating relatively flat terrain on the floor of Jezero Crater. However, the recent successful navigation of the challenging boulder-filled terrain at Snowdrift Peak stands out as a remarkable achievement. Even the engineers responsible for planning the rover’s movements were impressed by Perseverance’s ability to handle such a demanding and rugged environment autonomously. This demonstrates the rover’s advanced capabilities and the effectiveness of its dual-computer system in navigating complex Martian terrain.
The new campaign will redemark new territory.
It’s mentioned that while the challenging boulder field is now behind Perseverance, the rover still faces more driving challenges as it continues its mission. On September 7, Perseverance began its fourth science campaign by crossing the “Mandu Wall,” which is a rolling ridgeline that separates two distinct geologic units on the inner edge of Jezero Crater’s western rim.
Orbital data suggests that this area is rich in carbonates, which are minerals that could provide valuable information about Mars’ environmental history and possibly preserve signs of ancient microbial life, if such life ever existed in the region.
The passage emphasizes that the days of rover science teams observing distant features on the Martian horizon and saving them for future consideration are over. Perseverance’s autonomous capabilities allow it to quickly respond to what it encounters, which means that something seen in the distance on one day can be investigated closely on the very next day, or even from behind the rover.
As Perseverance explores this new terrain, it will encounter various challenges, including broken bedrock, steeper slopes, sand dunes, and small impact craters. Despite these potential obstacles, the rover’s team is prepared for the new exploration possibilities and challenges. They recognize that this diverse terrain is where the scientific discoveries are waiting to be made, and they are confident in Perseverance’s abilities, including its AutoNav system, to navigate and collect data effectively in this environment.