NASA’s new Sample Recovery Helicopters will make flying on Mars less ‘boring’

In the Jezero Crater of Mars, NASA's Perseverance rover is now gathering soil and rock samples that will eventually be sent back to Earth. According to the present plan, the sample tubes will be delivered by the rover to a Mars lander in 2030 so that they may be sent back to Earth. As the NASA Mars Sample Return team stated in late July, two tiny helicopters would be ready to intervene if something goes wrong.

The Sample Recovery Helicopters would be the second and third rotorcraft to ever take flight on another planet if that were to happen. Additionally, their presence in the NASA and ESA-led Mars Sample Return mission may herald the start of a new era in Mars exploration, one in which tiny, lightweight helicopters routinely fly around the planet.

Just over a year has passed since NASA's Ingenuity helicopter first sailed to the skies of Mars in April 2021, making the announcement of the addition of helicopters to the Mars Sample Return mission exciting. The experimental rotorcraft has flown 28 additional times since then, significantly exceeding expectations.

Teddy Tzanetos, the Ingenuity Mars Helicopter Team Lead at NASA's Jet Propulsion Laboratory, explains that the project's entire goal was to be the Wright Brothers moment that eventually leads to more aerial exploration of Mars. "Ingenuity wanted to make flying dull... We may now continue taking dull flights while engaging in fascinating activities while they are being taken.

The original Mars Sample Return mission design called for the use of a "fetch rover," a machine that could retrieve samples that had previously been stored in tubes by the Perseverance rover. The sample tubes would have been transported several hundred yards over the Martian surface by the fetch rover to a lander close to Jezero Crater, where they would have been loaded into the Mars Ascent Vehicle. The sample tubes' container would then be sent into orbit by the rocket-powered ascent vehicle, where a spacecraft with an Earth-return mission was waiting.

However, according to Ann Devereaux, the Deputy Program Manager for the Mars Sample Return mission, "it was difficult to acquire a rover that was big enough and capable enough to go and do a fair job of collecting samples." Creating and delivering such a rover alongside the Mars Ascent Vehicle would be expensive.

While Ingenuity was conducting its initial test flights, the crew started investigating alternative ideas. The engineers looked at whether helicopters may be the best choice for retrieving the samples stashed by Perseverance once the rotorcraft proven to be successful.

This sailplane could travel across Mars for months on nothing but wind.

According to Devereaux, in many circumstances, helicopters are more compact, lightweight, and maneuverable than rovers. The aircraft don't have to worry about navigating sand dunes on heavy tires, even if they require a safe spot to land.

The sample return helicopter designs won't deviate significantly from Ingenuity. Heritage is crucial when discussing robots in space, according to Tzanetos. Because we know that Ingenuity design is dependable and resilient, we aim to keep as closely to it as possible.

He argues that any aircraft on Mars must be extremely light and have big, quickly rotating rotor blades to create enough lift due to the thinness of the Martian air, which is only 1% of Earth's density. NASA's aerodynamic calculations were proved to be accurate by Ingenuity's repeated flights; as a result, the models will direct how engineers construct the next pair of flying robots.

We may now just continue taking dull flights and engaging in fascinating activities while they are being taken.

But the helicopters used for sample recovery won't be an identical clone of Ingenuity. These two rotorcraft will need to do more than simply fly, according to Tzanetos, therefore the team will need to make some adjustments. According to him, they will have to fly 2,300 feet from the lander to the cache depot location, pick up a tube, drop it off in a predetermined drop-off point, and then repeat the process 15 times.

The helicopters will thus have to carry greater weight than the 4-pound Ingenuity. According to Tzanetos, the current concept design for the sample retrieval helicopters asks for more equipment that may add another pound to the robots, such as arms to pick up samples and wheels to move about at the cache depot and drop spots.                                                                                                  

We've calculated it, and we know there are some adjustments we can make to the rotor system to enable it to lift greater mass, he says. Tzanetos and his team are concentrating on making those adjustments now that the Mars Sample Return mission directors have chosen to move forward with the retrieve helicopter design.

They start by figuring out how far they can stretch the original rotor system from Ingenuity. The test helicopter was built with greater lift than was considered essential by the engineers in case the Martian environment proved to be more difficult than the team's predictions indicated.

In order to balance out all of these various mass uses, he says, "we're beginning to work on figuring out what is the best spot." "We can carry a heavier aircraft that allows us to complete the task," the pilot said. "We can spin the blades somewhat quicker, we can demand more out of the rotor system, for example.

Nevertheless, it's possible that the helicopters won't even be necessary. Just in case the Perseverance rover is unable to deliver samples or dies before the retrieval is finished, they will be sent to Mars.

However, the success of Ingenuity may have already prophesied the future of helicopters on Mars.

Devereaux exclaims, "This helicopter has been wonderful," citing Ingenuity's demonstration of its ability to fly in front of the Perseverance rover and scout ahead for the rover's on-the-ground investigation. She continues by saying that helicopters provide us a different viewpoint of our neighboring world. The valleys that make up Valles Marineris may one day be traversed by rotorcraft that resemble drones, showing the Red Planet's geologic strata up close where rovers are unable to venture.

For Martian exploration, "rovers have now become widespread," according to Tzanetos. "We know how to create rovers, and we know how to use rovers. I'm hopeful that in a few decades, we'll be able to say the same thing about helicopters. He speculates that fleets of aircraft with plane- or copter-like wings may one day dominate the Martian sky.