Ingenuity (helicopter)

Ingenuity (helicopter)
Ingenuity, nicknamed Ginny, is a small autonomous helicopter presently operating on the planet Mars. It is part of NASA's Mars 2020 mission. The helicopter arrived on the Martian surface attached to the underside of the Perseverance rover, which landed on February 18, 2021. The helicopter was deployed to the surface on April 3, 2021. Both the rover and the helicopter began their missions on Mars at the Octavia E. Butler Landing site near the western rim of the wide Jezero crater.
On April 19 it made the first powered, controlled extraterrestrial flight by any aircraft. During its first flight Ingenuity took off vertically, hovered, and then landed. It flew for a total of 39.1 seconds during that attempt. As of its 64th flight on October 27, 2023, Ingenuity had flown a total of 1 hour, 57 minutes and 36 seconds over days.
The flights have demonstrated the helicopter's ability to fly in the extremely thin atmosphere of Mars, just 0.6% as thick as the air on Earth. It proved that flight was possible on other planets without the direct human control that the finite speed of light makes impractical (depending on the positions of the two planets, radio signals take between 5 and 20 minutes to travel between the Earth and Mars). As a result of this delay Ingenuity must autonomously perform the maneuvers planned, scripted and transmitted to it by its operators.
The helicopter was intended to perform a 30-sol technology demonstration, making five flights at altitudes ranging from for up to 90 seconds each. Before Ingenuity's first flight, Perseverance drove approximately away to create a safety buffer between itself and the helicopter. The success of Ingenuity's first flight was confirmed three hours after its completion by JPL, which livestreamed a view of mission control receiving the data. On April 30, 2021, during its fourth flight, Perseverance recorded the sound of Ingenuity during operation, making it the first interplanetary spacecraft whose sound was recorded in situ by another interplanetary spacecraft.
After a brief demonstration phase to prove its airworthiness, JPL commenced a series of flights designed to show how aerial scouting could aid the exploration of Mars and other worlds. In this operational role Ingenuity now scouts areas of interest for the Perseverance rover.
The helicopter's performance and resilience in the harsh Martian environment have greatly exceeded expectations. The aircraft surpassed its required altitude and flight duration specifications soon after beginning operations on Mars. This allowed Ingenuity to perform far more flights than were initially expected of the aircraft. It flew during the remainder of 2021 and into 2022. In March 2022 NASA announced that it would extend Ingenuity's mission and continue to fly the aircraft through at least September of that year. As of it continues to perform successful flights, providing scientific data and site scouting to Perseverance.
Ingenuity was designed by NASA's Jet Propulsion Laboratory (JPL) in collaboration with AeroVironment, NASA's Ames Research Center and Langley Research Center. Contributors of key components included Lockheed Martin Space, Qualcomm, and SolAero.
Development
Concept
The development of the project that would eventually become Ingenuity started in 2012 when JPL director Charles Elachi toured and met with members of the Autonomous Systems Division at JPL. The idea for the project drew on prior concept work in the division. By January 2015, NASA agreed to fund the development of a full-size model, which came to be known as the "risk reduction" vehicle.
NASA's JPL and AeroVironment published the conceptual design in 2014 for a scout helicopter to accompany a rover. By mid-2016, $15 million was being requested to continue development of the helicopter.
By December 2017, engineering models of the vehicle had been tested in a simulated martian atmosphere and models were undergoing testing in the Arctic, but its inclusion in the mission had not yet been approved or funded.
Mission integration
At the time of the approval of the Mars 2020 program in July 2014, a helicopter flight demonstration was neither scoped nor budgeted.
The United States federal budget, announced in March 2018, provided $23 million for the helicopter for one year, and it was announced on May 11, 2018, that the helicopter could be developed and tested in time to be included in the Mars 2020 mission. The helicopter underwent extensive flight-dynamics and environment testing, and was mounted on the underside of the Perseverance rover in August 2019. NASA spent about $80 million to build Ingenuity and about $5 million to operate the helicopter.
In 2019, preliminary designs of Ingenuity were tested on Earth in simulated Mars atmospheric and gravity conditions. For flight testing, a large vacuum chamber was used to simulate the very low pressure of the atmosphere of Mars – filled with carbon dioxide to approximately 0.60% (about ) of standard atmospheric pressure at sea level on Earth – which is roughly equivalent to a helicopter flying at altitude in the atmosphere of Earth. In order to simulate the much-reduced gravity field of Mars (38% of Earth's), 62% of Earth's gravity was offset by a line pulling upwards during flight tests. A "wind-wall" consisting of almost 900 computer fans was used to provide wind in the chamber.
In April 2020, the vehicle was named Ingenuity by Vaneeza Rupani, a girl in the 11th grade at Tuscaloosa County High School in Northport, Alabama, who submitted an essay into NASA's "Name the Rover" contest. Known in planning stages as the Mars Helicopter Scout, or simply the Mars Helicopter, the nickname Ginny later entered use in parallel to the parent rover Perseverance being affectionately referred to as Percy. Its full-scale engineering model for testing on Earth - Earth Copter and unofficially Terry.
Ingenuity was designed to be a technology demonstrator by JPL to assess whether such a vehicle could fly safely. Before it was built, launched and landed, scientists and managers expressed hope that helicopters could provide better mapping and guidance that would give future mission controllers more information to help with travel routes, planning, and hazard avoidance. Based on the performance of previous rovers through Curiosity, it was assumed that such aerial scouting might enable future rovers to safely drive up to three times as far per sol. However, the new AutoNav capability of Perseverance significantly reduced this advantage, allowing the rover to cover more than 100 meters per sol.
Development team
The Ingenuity team was comparatively small, with never more than 65 full-time-equivalent employees at JPL. Program workers at AeroVironment and NASA AMES and Langley research centers brought the total to 150. Key personnel include:
MiMi Aung – Ingenuity Mars Helicopter Project Manager at NASA's Jet Propulsion Laboratory,
Bob Balaram – Chief Engineer (prior to Nov 2021)
Timothy Canham – Flight Software Lead and Operations Lead (prior to June 2021)
Håvard Fjær Grip – GNC Lead and Chief Pilot
Matt Keennon – AeroVironment Technical Lead
Ben Pipenberg – AeroVironment Design Lead
Josh Ravich – Mechanical Engineering Lead
Teddy Tzanetos – Operations Lead
On June 15, 2021, the team behind Ingenuity was named the 2021 winner of the John L. "Jack" Swigert Jr. Award for Space Exploration from the Space Foundation. On April 5, 2022, the National Aeronautic Association awarded Ingenuity and its group in JPL the 2021 Collier Trophy.
Opposition to the helicopter
The idea to add a helicopter to a Mars mission was opposed by multiple people. Up until the end of the 2010s, several NASA leaders, scientists and JPL employees actively put forward counterarguments against the integration of a helicopter into the next expedition. For three years, the future Ingenuity has been developed outside the Mars 2020 project and its budget. When NASA management accepted assurances in the spring of 2018 that the addition of a helicopter would not harm the goals of the expedition, the chief scientist of this project Kenneth Farley stated that it does not follow from the fact that Ingenuity was taken on board that the team supported this decision even with guarantees of no risk. Farley was convinced that the helicopter was a distraction of a group of scientists from a priority scientific task, unacceptable even for a short time.
The skepticism on the part of NASA leadership was not unfounded. Scientists, engineers and managers proceeded from a pragmatic comparison of the benefits of additional aerial reconnaissance with the costs that inevitably fall on the schedule for the rover to complete all the tasks assigned to it. Arguing with MiMi Aung on the air of a joint conference, Jennifer Trosper warned that thanks to auto-navigation, the rover ultimately outpaces the helicopter. These calculations were first confirmed in the spring of 2022 when by the beginning of Sol 400 the helicopter did not take a leading position on the track along the slopes of the delta, although it covered a distance several times less than the rover. Due to the increased loss of time for recharging and transmitting telemetry, the attempt to bring the helicopter to the position of the route plotter, planned during the ascent to the delta, also failed.
At the end of the "test window", NASA extended support for Ingenuity for another 30 sols, limiting the frequency of departures to 1 flight every few weeks. Later on, some of NASA's senior leaders seized the opportunity to dampen their enthusiasm for the Martian helicopter. Thus, addressing directly all the staff of the Mars 2020 project, the director of the Mars exploration program E. Janson and the principal Mars explorer M. Meyer urged the staff to “be highly disciplined and concentrate on collecting samples”. At the same time, in their report to the Planetary Advisory Committee (PAC) on June 14, 2021, the helicopter was mentioned only in the past tense: "placed Ingenuity and completed the technology demonstration phase".
Despite this early pessimism, Ingenuity has since proved to be more than capable of keeping up with Perseverance, actually staying ahead of the rover for the majority of the traverse up the Jezero delta.
Insufficient solar energy during the Martian winter was the main driver of poor operational performance in the latter half of 2022.
Design
Mechanical design
Ingenuity consists of a rectangular fuselage measuring suspended below a pair of coaxial counter-rotating rotors measuring in diameter. This assembly is supported by four landing legs of each. It also carries a solar array mounted above the rotors to recharge its batteries. The entire vehicle is tall.
The lower gravity of Mars (about a third of Earth's) only partially offsets the thinness of the 95% carbon dioxide atmosphere of Mars, making it much harder for an aircraft to generate adequate lift. The planet's atmospheric density is about that of Earth's at sea level, or about the same as , an altitude never reached by existing helicopters. This density reduces even more in Martian winters. To keep Ingenuity aloft, its specially shaped blades of enlarged size must rotate between 2400 and 2900 rpm, or about 10 times faster than what is needed on Earth.
Each of the helicopter's contra-rotating coaxial rotors are controlled by a separate swashplate that can affect both collective and cyclic pitch.
Although it is an aircraft, it was constructed to spacecraft specifications to endure the acceleration and vibrations during launch.
Avionics
Ingenuity relies on different sensor packages grouped in two assemblies. All sensors are commercial off-the-shelf units.
The Upper Sensor Assembly, with associated vibration isolation elements, is mounted on the mast close to the vehicle's center-of-mass to minimize the effects of angular rates and accelerations. It consists of a cellphone-grade Bosch BMI-160 Inertial measurement unit (IMU); and an inclinometer (Murata SCA100T-D02), which is used only on the ground prior to flight to calibrate the IMU accelerometers biases. The Lower Sensor Assembly consists of an altimeter (Garmin LIDAR Lite v3), cameras, and a secondary IMU, all mounted directly on the Electronics Core Module (not on the mast).
Ingenuity uses a 425×165 mm solar panel to recharge its batteries, which are six Sony Li-ion cells with of energy capacity (nameplate capacity of 2 Ah). Flight duration is not constrained by the available power, but by the motors heating up 1 °C every second.
The helicopter uses a Qualcomm Snapdragon 801 processor with a Linux operating system. Among other functions, it controls the visual navigation algorithm via a velocity estimate derived from terrain features tracked with the navigation camera. The Qualcomm processor is connected to two radiation-resistant flight-control microcontroller units (MCUs) to perform necessary control functions under Mars's conditions.
The telecommunication system consists of two identical radios with monopole antennae for data exchange between the helicopter and rover. The radio link utilizes the low-power Zigbee communication protocols, implemented via 914 MHz SiFlex 02 chipsets mounted in both vehicles. The communication system is designed to relay data at 250 kbit/s over distances of up to . The antenna on the helicopter's solar panel weighs 4 grams and can communicate equally in all directions.
Cameras and photography
[[File:PIA23969-Ingenuity Helicopter Imaging Suite.jpg|thumb|Ingenuity'''s two cameras, as seen from under the aircraft]]Ingenuity is equipped with two commercial-off-the-shelf (COTS) cameras: a high-resolution Return to Earth (RTE) camera and a lower resolution navigation (NAV) camera. The RTE camera consists of the Sony IMX 214, a rolling shutter, 4208 × 3120-pixel resolution color sensor, fitted with a Bayer color filter array and an O-film optics module. The NAV camera consists of an Omnivision OV7251, a 640 × 480 black and white global shutter sensor, mounted to a Sunny optics module.
Unlike Perseverance, Ingenuity does not have a special stereo camera for taking twin photos for 3D pictures simultaneously. However, the helicopter can make such images by taking duplicate color photos of the same terrain while hovering in slightly offset positions, as in flight 11, or by taking an offset picture on the return leg of a roundtrip flight, as in flight 12.
[[File:Combination of two images, one each from Ingenuity's Navigation Camera and colour camera (RTE).jpg|thumb|Combination of two images, one each from Ingenuitys Navigation Camera and colour camera (RTE), taken while Ingenuity was on the ground.]]
While the RTE color camera is not necessary for flights (as in flights 7 and 8), the NAV camera operates continuously throughout each flight, with the captured images used for visual odometry to determine the aircraft's position and motion during flight. Due to limitations on the transmission rate between the aircraft, the rover, and Earth, only a limited number of images can be saved from each flight. Images to save for transmission are defined by the flight plan prior to each flight, and the remaining images from the NAV camera are discarded after use.
As of December 16, 2021, 2091 black-and-white images from the navigation camera and 104 color images from the terrain camera (RTE) have been published.
Flight software
The helicopter uses autonomous control during its flights, which are telerobotically planned and scripted by operators at Jet Propulsion Laboratory (JPL). It communicates with the Perseverance rover directly before and after each landing.
The flight control and navigation software on the Ingenuity can be updated remotely, which has been used to correct software bugs and add new capabilities as the helicopter continues to operate beyond its original mission. Prior to flight 34, the software was updated to avoid hazards during landing and to correct a navigation error when traveling over uneven terrain. This update became necessary as the helicopter traveled away from the relatively flat terrain of the original landing site, and towards more varied and hazardous terrain.
Specifications
Operational history
The Ingenuity helicopter was originally intended to fly up to five times during a 30-sol test campaign, early in the rover's mission.
Primary mission
Perseverance dropped the debris shield protecting Ingenuity on March 21, 2021, and the helicopter deployed from the underside of the rover to the martian surface on April 3, 2021. That day both cameras of the helicopter were tested taking their first b/w and color photos of the floor of Jezero Crater in the shadow of the rover. After deployment, the rover drove approximately away from the drone to allow a safe flying zone.
Ingenuity rotor blades were successfully unlocked on April 8, 2021, (mission sol 48), and the helicopter performed a low-speed rotor spin test at 50 rpm.
A high-speed spin test was attempted on April 9, but failed due to the expiration of a watchdog timer, a software measure to protect the helicopter from incorrect operation in unforeseen conditions. On April 12, JPL said it identified a software fix to correct the problem. To save time, however, JPL decided to use a workaround procedure, which managers said had an 85% chance of succeeding and would be "the least disruptive" to the helicopter.
On April 16, 2021, Ingenuity successfully passed the full-speed 2400 rpm rotor spin test while remaining on the surface. Three days later, April 19, JPL flew the helicopter for the first time. The watchdog timer problem occurred again when the fourth flight was attempted. The team rescheduled the flight, which succeeded on April 30. On June 25, JPL said it had uploaded a software update the previous week to permanently fix the watchdog problem, and that a rotor spin test and the eighth flight confirmed that the update worked.
Each flight was planned for altitudes ranging above the ground, though Ingenuity soon exceeded that planned height. The first flight was a hover at an altitude of , lasting about 40 seconds and including taking a picture of the rover. The first flight succeeded, and subsequent flights were increasingly ambitious as allotted time for operating the helicopter dwindled. JPL said the mission might even stop before the 30-day period ended, in the likely event that the helicopter crashed, an outcome which did not occur. In up to 90 seconds per flight, Ingenuity could travel as far as downrange and then back to the starting area, though that goal was also soon exceeded with the fourth flight.
After the successful first three flights, the objective was changed from technology demonstration to operational demonstration. Ingenuity flew through a transitional phase of two flights, flights 4 and 5, before transitioning to its operations demonstration phase.
Operations Demo Phase
Just prior to the final demonstration flight, on April 30, 2021, NASA allocated funding to continue the operation of Ingenuity for an “operational demonstration phase” to explore using a helicopter as supplementary reconnaissance for ground assets like Perseverance. Funding for Ingenuity is regularly renewed on a monthly basis.
Starting with the 6th flight, the mission goal shifted towards supporting the rover science mission by mapping and scouting the terrain. While Ingenuity would do more to help Perseverance, the rover would pay less attention to the helicopter and stop taking pictures of it in flight. JPL managers said the photo procedure took an "enormous" amount of time, slowing the project's main mission of looking for signs of ancient life. On 30 April 2021, the fourth flight successfully captured numerous color photos and explored the surface with its black-and-white navigation camera. On May 7, Ingenuity successfully flew to a new landing site.
After 12 flights by September 2021, the mission was extended indefinitely. After 21 flights by March 2022, NASA said it would continue flying Ingenuity until at least the coming September. The area of the helicopter's next goal is more rugged than the relatively flat terrain it flew over in its first year of operation. The ancient fan-shaped river delta has jagged cliffs, angled surfaces and projecting boulders. Ingenuity will help the mission team decide which route Perseverance should take to the top of the delta and may aid in analyzing potential science targets. Software updates will eliminate the helicopter's 50-foot altitude limit, allow it to change speed in flight, and improve its understanding of terrain texture below it. NASA associate administrator Thomas Zurbuchen said less than a year earlier "we didn't even know if powered, controlled flight of an aircraft at Mars was possible." He said the transformation in understanding what the aircraft can do is "one of the most historic in the annals of air and space exploration."
The Ingenuity team plans to fly the helicopter every two to three weeks during its indefinitely extended mission. The helicopter's longer-than-expected flying career lasted into a seasonal change on Mars, when the atmospheric density at its location became even lower. The flight team prepared by commanding Ingenuity to ground test a faster rotor blade rotation, needed for sufficient lift. JPL said the higher planned flight speed of 2700 rpm would pose new risks, including vibration, power consumption and aerodynamic drag if the blade tips approach the speed of sound. The test speed was 2800 rpm, giving a margin for increase if the intended flight speed of 2700 is not enough. Ingenuity faced another challenge to remain functional during the Martian winter and solar conjunction, when Mars moves behind the Sun, blocking communications with Earth and forcing the rover and helicopter to halt operations. The shutdown happened in mid-October 2021, for which preparations started in mid-September. The helicopter remained stationary at its location away from Perseverance and communicated its status weekly to the rover for health checks. JPL intended to continue flying Ingenuity since it survived solar conjunction. NASA leadership has stated that extending the mission will increase the project's expenses, but that they believe the cost to be worthwhile for the information learned.
The start time of a flight is chosen depending on temperature management of the batteries, which need to warm up after the night. During Martian summer lower air density imposed a higher load on the motors, so flights were shifted from noon (LMST 12:30) to morning (LMST 9:30) and limited to 130 seconds to not overheat the motors.
On May 3 and 4, 2022, for the first time in the mission, the helicopter unexpectedly failed to communicate with the rover, following the 28th flight on April 29. JPL determined that Ingenuity'''s rechargeable batteries suffered a power drop or insufficient battery state-of-charge (SOC) while going into the night, most likely because of a seasonal increase in atmospheric dust reducing sunshine on its solar panel and due to lower temperatures as winter approached. When the battery pack's state of charge dropped below a lower limit, the helicopter's field-programmable gate array (FPGA) powered down, resetting the mission clock, which lost sync with the base station on the rover. Contact was re-established on May 5. Controllers decided to turn off the helicopter's heaters at night to conserve power, accepting the risk of exposing components to nighttime's extreme cold.
This daily SOC deficit is likely to persist for the duration of Martian winter (at least until September/October). Each sol could be Ingenuity's last.
In a June 6, 2022, update, JPL reported Ingenuity's inclination sensor had stopped working. Its purpose was to determine the helicopter's orientation at the start of each flight. Mission controllers developed a workaround using the craft's inertial measurement unit (IMU) to provide equivalent data to the onboard navigation computer.
In January 2023, the helicopter began to have enough solar power to avoid overnight brownouts and FPGA resets due to the start of Martian spring. This means the helicopter will be able to fly more frequently and over longer distances.
In March 2023, the helicopter made frequent flights to deal with limited radio range in the rough terrain of the Jezero delta. In the narrow canyons of the river delta it's impossible to pass the rover without violating the wide keep out zone.
Follow-on missions and future work
There are currently no plans to send Curiosity/Perseverance-class scientific laboratories to Mars, and funding for Martian projects is frozen to the level necessary to complete the Mars sample-return campaign.
Sample Return Helicopter
The idea of future Martian helicopters has been proposed. In March 2022, AeroVironment engineers, who previously created Ingenuity, presented the concept of a new helicopter with a payload of 280 g. A 90 g small manipulator arm with a two-fingered gripper and a self-propelled landing gear make it possible to use vehicles of this type instead of a fetch rover to select sample tubes cases with samples collected by Perseverance. At a briefing on September 15, 2022, NASA Planetary Science Division Director Laurie Gleizes confirmed her intention to use two of these helicopters.
The choice of Ingenuity as the prototype for the intended pair of assembler helicopters was based on the impressive safety margin built into it by AeroVironment designers. In principle, even the limit of 100 landings for the high-wear shock absorbers of the chassis is sufficient to transfer all 43 sleeves. Multiple small payloads can be carried by these types of helicopters, deployed and re-deployed to various locations, to perform a variety of distributed and networked operations.
Inertial navigation was one of the main challenges on Mars for the Ingenuity. The helicopter needs to show the ability to accurately follow the track it has already "mapped" on previously collected NAV frame sets and land at the takeoff point. In a future sample return mission, each cartridge case would require a pair of flights ending at the point of departure. Landing accuracy was an assigned task of Ingenuity's 31st flight. The very thin atmosphere of Mars does not allow repeating the maneuvers and landing techniques of terrestrial helicopters.
Mars Science Helicopter
Data collected by Ingenuity are intended to support the development of future helicopters capable of carrying larger payloads.
Tributes to the Wright brothers
NASA and JPL officials described the first Mars Ingenuity helicopter flight as their "Wright Brothers moment", by analogy to the first successful powered airplane flight on Earth. A small piece of the wing cloth from the Wright brothers' 1903 Wright Flyer is attached to a cable underneath Ingenuitys solar panel. In 1969, Apollo 11's Neil Armstrong carried a similar Wright Flyer artifact to the Moon in the Lunar Module Eagle.
NASA named Ingenuity first take-off and landing airstrip Wright Brothers Field, which the UN agency ICAO gave an airport code of JZRO for Jezero Crater, and the drone itself a type designator of IGY, call-sign INGENUITY.
Gallery
Audio
Videos
Deployment sequence
Maps of flights
{{multiple images |align=center |direction=horizontal |total_width=800
|header = Flights' paths of the operational demonstration stage and HiRise images of Ingenuity|image5 = 26339 PIA24977 Flight Profile for Ingenuity's Flight 15.jpg
|caption5 = Flight profile for Ingenuitys Flight 15
|image6 = 26396 PIA24980-webTopography an Between Mars Helicopter and Rover for Flight 17.jpg
|caption6 = Topography between Mars helicopter and rover for Flight 17
|image7=Perseverance and Ingenuity wait out the solar conjunction.png
|caption7=Positioning before the 2021 solar conjunctionR210 is the rover position on sol 210;H, H and H means 1st, 2nd and 3rd landing sites of Ingenuity on the Field H on sols 163, 174 and 193 respectively
|image8=PIA25174 Ingenuity captured by Hirise camera on mars reconaissance orbiter.jpg
|caption8=Ingenuity captured by HiRise camera on Mars Reconnaissance Orbiter at Airfield M on February 26, 2022
}}
Images by Ingenuity
Motion images
Self-portraits by Perseverance
See also
Atmosphere of Mars – Less than 1% of the Earth's atmosphere pressure and primarily composed of carbon dioxide (95% ), molecular nitrogen (2.8%, N2) and argon (2% Ar)
Dragonfly – Robotic rotorcraft mission to Saturn's moon Titan, planned launch in 2027
Exploration of Mars
List of artificial objects on Mars
List of firsts in aviation
Solar panels on spacecraft
Vega – The USSR space program that included the first atmospheric balloon flight on Venus, in 1985
Collier Trophy – Presented to the Ingenuity team in 2022 for "the greatest achievement in aeronautics or astronautics in America during the preceding year"
Notes
References
Status reports
External links
NASA Mars Helicopter webpage
NASA Mars Helicopter flight log
Mars Helicopter Technology Demonstrator. (PDF) – The key design features of the prototype drone.
Perseverance Route Map – including the flight tracks of Ingenuity
Explore Mars
AIAA Book Planetary Exploration with Ingenuity and Dragonfly
source code of program behind Ginny – NASA GitHub page
2020 in the United States
2020 robots
Aircraft with counter-rotating propellers
Coaxial rotor helicopters
Electric helicopters
Extraterrestrial aircraft
Individual space vehicles
Missions to Mars
NASA aircraft
NASA space probes
Space probes launched in 2020
Unmanned helicopters
2021 on Mars
Mars robots