When NASA’s latest Mars Perseverance router launches this week, the robot will have a tiny passenger on board: a small box-shaped helicopter. If the helicopter succeeds in soaring over the terrain of Mars, it will be the first time a man-made vehicle has ever flown to another world – and this could open up a whole new way to explore the solar system in the future.
A helicopter named Ingenuity is not the main focus of a rover. The ultimate goal of perseverance is to look for signs of life on Mars and to dig up examples of impurities that could one day be returned to Earth for study. But engineers managed to find a room under the rover’s belly to stack a tiny helicopter. At some point during the perseverance journey, the rover will use ingenuity on the surface of Mars, where he will rotate his rotor and try to rise.
This interplanetary experiment hopes to give a new advantage to the study of Mars, beyond the current ̵1; limited – possibilities. The orbits of Mars cannot receive the high-resolution images that the spacecraft can reach near Earth. Detainees can only get information from a fixed location, and SUVs can only move so far with limited information about what’s waiting. However, a helicopter can be a scout exploring other spacecraft or reaching hard-to-reach areas.
That reconnaissance ability could be very useful if humans ever got to the surface of Mars. “By really flying forward and receiving high-resolution images to inform people and travelers, you’ll definitely accelerate the exploration of the world,” said MiMi Aung, Mars Helicopter Project Manager at NASA’s Jet Propulsion Laboratory. “Being able to fly will bring new aspects of research.”
There is still a very big hurdle to fly to Mars: the atmosphere. The air surrounding the planet makes up just 1 percent of the Earth’s atmospheric thickness. If you move so little air, it will be very difficult to reach Mars. The low gravity on the surface of Mars helps; that is about 38 percent of the earth’s gravity. But even with that kind of help, a vehicle still can’t fly to Mars with the same technology we use to fly on our planet.
To keep things from falling in that environment, it has to be extremely light and the propeller has to move incredibly fast. But they can’t go also soon, or things start to fade. “You can’t drive faster and faster because then the blade tips happen to approach Mach,” says Bob Balaram, chief engineer of the JPL Mars helicopter. Threshold. “They’re starting to want a supersonic sound, and you don’t even want to let them switch to the sound because you’re getting a lot of restless effects.”
Given these limitations, NASA’s team of JPL engineers decided to come up with the first Mars helicopter. Behind Perseverance, the team determined the dimensions of the helicopter and determined that the rover could accommodate a small helicopter with a blade about 1.2 meters wide or about 4 feet wide. This eventually dictated the weight of the helicopter, weighing just 1.8 kilograms or about 4 pounds. Creating such a small vehicle filled with electronics is just something that could have happened today, Aung says. “Decades ago, lightweight electronics – computers, sensors, cameras, gyroscopes – weren’t all there,” she says.
The final helicopter design looks like a daddy spider with long legs with a confused head. The main body of ingenuity is a box with four protruding limbs that hold the vehicle in a vertical position. Mounted on top are four carbon fiber blades, as well as a solar cell to generate energy. Those blades are designed to rotate up to 2400 rpm – or 40 times per second. A conventional ground helicopter blade rotates at approximately 450-500 rpm. However, the ingenuity of the blade should not exceed the speed of sound and should be less than 0.7 Mach.
The ingenuity of construction, however, was only half the battle. The team had to make sure the helicopter could actually fly to another world. “The invention of the helicopter is also,‘ How to test this? “Says Aung. “Because it’s never been done before.”
Fortunately, NASA’s jet propulsion laboratory is equipped with huge test facilities that could be used for this work. A large JPL camera, called a space simulator, can re-create a full vacuum and manipulate all the extreme temperatures that a spacecraft can experience as it exits Earth. To test their ingenuity, a team of engineers turned the camera into a Mars-like environment. “We basically took that chamber, pumped it to near vacuum, and refilled it with carbon dioxide so that the room now had the atmospheric density of Mars,” says Aung.
Another challenge remains: get rid of the weight of the earth. Simulating the lower gravity of Mars, engineers attached an easy attachment to ingenious prototypes as they flew in a test chamber. Turning to the gravity unloading system, the belt constantly led the spacecraft’s tug up, making it feel as if the vehicle was 38 percent of the earth’s weight.
This testing helped shape the final ingenuity design. During the first couple, the flight test team found that the blades of the test helicopter were constantly fluttering up and down. The tendency to oscillate also happens with ground helicopters because the blade is long and nutty. However, the dense atmosphere suppresses that effect. On the other hand, the thin atmosphere of Mars does not reduce that chatter.
“It was a bit of a discovery when we made the first flights,” Balaram says, adding that the beating could have disrupted the operation of the helicopter. The solution? Engineers made the blades particularly rigid, much stiffer than a conventional helicopter of a similar size would be on Earth.
The team conducted dozens of test flights in a variety of extreme conditions, including deep cold, to simulate the nights of Mars, which can reach -130 degrees Fahrenheit or -90 degrees Celsius. Now, after all that hard work, it’s time for ingenuity to start its journey. To get to Mars, the helicopter will ride folded on the bottom of the perseverance, covered with a shield for protection. Once the rover enters Mars and finds the right place, Ingenuity will perform some challenging gymnastic exercises, protruding into the final shape with his feet pointing to the ground. Then he will fall to the surface as Perseverance will turn away and leave him.
The ingenuity gave the team just 30 days on Mars, which is about 31 Earth days. The very first flight will be simple: the helicopter will try to take off and climb to a height of about 10 feet or 3 meters, taking off there in about 30 seconds. It will be short, but it will determine if all the hard work of the engineers has paid off. “I think I would feel this way: finally, our child is, so to speak, in an environment that has been created all these years,” says Aung.
Ingenuity will make up to four short flights, pushing the envelope with each gradual takeoff. No flight will last longer than about 90 seconds. However, ingenuity can reach up to about 15 feet or 5 meters in height and travel horizontally at a distance of about 160 feet or 50 meters.
All of these flights will have to be independent, as the connection between Earth and Mars takes a long time. The team will send the Ingenuity team a list of commands and perform all actions independently. The helicopter is designed to capture images as it flies, and it is possible that perseverance may also capture some distant images of ingenuity hanging in the air.
At the end of the day, ingenuity is a demonstration of technology, so its flights should be short and clear. But this could prove that flying machines could be valuable for future missions to Mars. Engineers are already working on designs for larger helicopters weighing up to 44 pounds or 20 kilograms. Larger copiers could carry far more important scientific knowledge and more beautiful cameras than what ingenuity now has.
But before you start walking, you have to scan first. That is what ingenuity is all about. “We hope to have what I want to call our Wright Brothers moment,” Balaram said. “But it’s a controlled flight on another planet.”