NASA preparing to fly Ingenuity Mars drone, enabling future airborne missions
As NASA’s newest Mars rover, Perseverance, continues its own checkouts and tests, work is starting for a new phase of the mission – the Ingenuity helicopter. This first-of-its-kind piece of hardware will demonstrate (non-rocket) powered flight on a world other than Earth for the first time. Data from these flights – expected to begin in 30-60 days – will help to develop future programs for missions to Mars and beyond.
Ingenuity is an experimental addition to the Mars 2020 mission. No matter the results of its test campaign, it will not have a significant effect on the primary mission.
Teams are planning for a 30 day flight window for the helicopter. They currently aim for a minimum of one flight, but that has the possibility of being extended. The first flight will feature a relatively simple 20-30 second low altitude hover test before landing. Afterwards, flights will last longer and travel farther.
Ingenuity features a pair of coaxial, 1.2 meter long, carbon fiber rotors. “Coaxial” means that the rotors are stacked on top of each other and spin in opposite directions, dramatically increasing the lift with a minimal increase in area.
The rotors will spin at a rate of 2,400 rotations per minute (RPM) – far higher than the approximately 500 RPM of many Earth-based helicopters. The rotors need to spin fast to account for the extremely thin Martian atmosphere.
The helicopter is powered by a single solar array above the rotors which charges six lithium-ion batteries. These batteries will enable Ingenuity to fly for up to 90 seconds at a time. A single 90 second flight – the maximum flight time of Ingenuity – will consume approximately 8.75 watt-hours – less energy than in an iPhone 12 battery.
Four carbon fiber legs sticking out of the corners of the main body will absorb any extra velocity and shocks upon landing.
The combination of its small size and large amount of composite materials makes Ingenuity especially light, massing 1.8 kilograms. On Earth, this equates to 17.7 Newtons (4.0 pounds), but in Mars‘ lower gravity, Ingenuity weighs only 6.7 Newtons (1.5 pounds).
Once it is deployed from Perseverance, Ingenuity will communicate with Earth through the rover. Each has a small antenna to talk to each other, and the rover will relay data back to Earth using its more powerful communications suite.
Throughout the cruise to Mars, Ingenuity communicated and received power directly through Perseverance.
On August 13, 2020, NASA announced that the helicopter was powered on and recharged in space for the first time. This was approximately two weeks after launch. The batteries were only charged to 35%, since each full charge and discharge of lithium-ion batteries slightly reduces their longevity. Keeping them at a low-to-medium charge level minimizes this impact.
Engineers then repeated this test approximately every two weeks during the cruise to Mars.
Perseverance – with Ingenuity attached on its belly – touched down on Mars on February 18, 2021.
The helicopter is currently still connected to Perseverance, as the latter completes its checkouts and initial operations on the Martian surface.
On March 2, the rover successfully deployed and tested its robotic arm. The arm contains several instruments and cameras, most notably the rover’s drill. It also features the PIXL and SHERLOC instruments – containing an x-ray and ultraviolet spectrometer, respectively. These will enable more detailed analysis of surface materials.