UAV set for historic Mars landing
We know this might have nothing to do with Africa but (in Spider Man’s voice, just after he was snapped back to life and reunites with Mr Stark for the first time), did you know they are sending a drone to Mars?
A drone. On Mars.
And it is going to happen today.
When the National Aeronautics and Space Administration’s (NASA) Mars 2020 Perseverance rover launched from Cape Canaveral Air Force Station in Florida on July 30 last year, on its way to the Jezero Crater on the Red Planet to look for signs of past life, it had onboard a special passenger – an autonomously flying helicopter called Ingenuity Mars Helicopter.
It weighs only 1.8 kilograms.
But do not be fooled by her feather weight; Ingenuity has ambitions the size of Mars itself.
According to Nasa, the Ingenuity UAV will make history as the first ever controlled flight off planet Earth. It features four specially made carbon-fibre blades, arranged into two rotors that spin in opposite directions at around 2,400 rpm – that is, many times faster than a passenger helicopter on Earth. The drone has to be made of light material and larger and faster spinning blades because Mars has a thin atmosphere (they say it is 99 percent less dense that it is on Earth) that would make it almost impossible to achieve lift off with heavier aerial vehicles.
“Ingenuity is intended to demonstrate technologies needed for flying in the Martian atmosphere,” NASA has said. “If successful, these technologies could enable other advanced robotic flying vehicles that might be included in future robotic and human missions to Mars. They could offer a unique viewpoint not provided by current orbiters high overhead or by rovers and landers on the ground, provide high-definition images and reconnaissance for robots or humans, and enable access to terrain that is difficult for rovers to reach.”
In other words, Ingenuity will be doing exactly what the drones on earth do – aerial surveys, and flying over and into places that are too dangerous for people to undertake. Only, since it will be on Mars, people will be replaced by the Perseverance rover. There are places on the red planet that are too dangerous for the rover to navigate safely; hence the idea to try aerial technology.
But the helicopter will have to make do with only 30 days for its maiden flight fancies; because after that, the rover will be on its way to other parts of the Mars world, to proceed with its primary mission. It will not wait while the drone gives itself the high fives over a successful inaugural flight; and if something bad were to happen, it will be left behind.
Speaking to IEEE Spectrum recently, Mars Helicopter Operations Lead at NASA’s Jet Propulsion Laboratory (JPL), Tim Canham, responded to question about the autonomous helicopter’s hardware and autonomous flight capabilities
First, the hardware
Since Ingenuity is classified as a technology demo, JPL is willing to accept more risk. The main unmanned projects like rovers and deep space explorers are what’s called Class B missions, in which there are many people working on ruggedized hardware and software over many years. With a technology demo, JPL is willing to try new ways of doing things. So we essentially went out and used a lot of off-the-shelf consumer hardware.
There are some avionics components that are very tough and radiation resistant, but much of the technology is commercial grade. The processor board that we used, for instance, is a Snapdragon 801, which is manufactured by Qualcomm. It’s essentially a cell phone class processor, and the board is very small. But ironically, because it’s relatively modern technology, it’s vastly more powerful than the processors that are flying on the rover. We actually have a couple of orders of magnitude more computing power than the rover does, because we need it. Our guidance loops are running at 500 Hz in order to maintain control in the atmosphere that we’re flying in. And on top of that, we’re capturing images and analysing features and tracking them from frame to frame at 30 Hz, and so there’s some pretty serious computing power needed for that. And none of the avionics that NASA is currently flying are anywhere near powerful enough. In some cases, we literally ordered parts from SparkFun (Electronics). Our philosophy was, “this is commercial hardware, but we’ll test it, and if it works well, we’ll use it.
And how does Ingenuity fly autonomously on an unfamiliar planet, where there will be a delay in communication, because of the sheer distance between Mars and the control centre?
You can almost think of the helicopter like a traditional JPL spacecraft in some ways. It has a sequencing engine on board, and we write a set of sequences, a series of commands, and we upload that file to the helicopter and it executes those commands. We plan the guidance part of the flights on the ground in simulation as a series of waypoints, and those waypoints are the sequence of commands that we send to the guidance software. When we want the helicopter to fly, we tell it to go, and the guidance software takes over and executes taking off, traversing to the different waypoints, and then landing.
This means the flights are pre-planned very specifically. It’s not true autonomy, in the sense that we don’t give it goals and rules and it’s not doing any on-board high-level reasoning. It’s sort of half-way autonomy. The brute force way would be a human sitting there and flying it around with joysticks, and obviously we can’t do that on Mars. But there wasn’t time in the project to develop really detailed autonomy on the helicopter, so we tell it the flight plan ahead of time, and it executes a trajectory that’s been pre-planned for it. As it’s flying, it’s autonomously trying to make sure it stays on that trajectory in the presence of wind gusts or other things that may happen in that environment. But it’s really designed to follow a trajectory that we plan on the ground before it flies.
This isn’t necessarily an advanced autonomy proof of concept—something like telling it to “go take a picture of that rock” would be more advanced autonomy, in my view. Whereas, this is really a scripted flight, the primary goal is to prove that we can fly around on Mars successfully. There are future mission concepts that we’re working through now that would involve a bigger helicopter with much more autonomy on board that may be able to [achieve] that kind of advanced autonomy. But if you remember Mars Pathfinder, the very first rover that drove on Mars, it had a very basic mission: Drive in a circle around the base station and try to take some pictures and samples of some rocks. So, as a technology demo, we’re trying to be modest about what we try to do the first time with the helicopter, too.
Which is all good and engaging to listen to, but to do all this, Ingenuity had to survive the flight launch and landing to Mars first, then safe deployment out of Perseverance’s underbelly onto the harsh, frigid reality on Mars’ surface. Dropping down to minus 90 degrees Celsius at night, the temperatures on Mars can bring boiled spaghetti to stand at attention in a heartbeat.
If it survives that, then there will only be the small matter of charging its innovative solar cells, batteries, and other components.
Then its off to the first ever controlled flight on Mars.
“The Wright Brothers showed that powered flight in Earth’s atmosphere was possible, using an experimental aircraft,” said Håvard Grip, Ingenuity’s chief pilot at NASA’s Jet Propulsion Laboratory in Southern California. “With Ingenuity, we’re trying to do the same for Mars.”
We will have our eye out, and hope Ingenuity get all the luck and success she deserves.