Ingenuity

Program pages NASA: Ingenuity

Ingenuity on the surface of Jezero crater, photographed by the Perseverance Mastcam-Z zoom cameras on sol 45, 5 April 2021, shortly after deployment from the rover's belly. The four blades of the coaxial counter-rotating rotor, the square solar panel above the rotor hub and the four landing legs are the whole vehicle; the fuselage between the legs holds the batteries and avionics NASA/JPL-Caltech/ASU. Public domain (NASA / US government work).

Overview

Ingenuity performed the first powered, controlled flight on another planet on 19 April 2021 [3]. Planned for five flights over thirty sols, it completed 72 flights over nearly three years before rotor damage ended operations in January 2024.

Specifications

Parameter	Value	Source
Mass	1.8 kg	[2], [11], [15]
Weight on Mars at g = 3.71 m/s2	6.75 N	[2]
Height	approximately 0.8 m	[9]
Rotor diameter / radius	1.21 m / 0.605 m	[2], [4]
Blades	two per rotor, four total, coaxial counter-rotating	[3]
Blade mass	approximately 28 g each	[2]
Design rotor speed	2600 rpm, operating to 2800 rpm	[4], [3]
Design flight endurance	90 s per sol on a single solar recharge	[11], [6], [15]

Mission profile

Parameter	Value	Source
Deployment	from the belly of Perseverance in Jezero crater	[15]
First flight	19 April 2021	[3], [15]
Planned campaign	five flights over thirty sols	[3]
Flights completed	72	[3], [15]
Total flight time	128.8 minutes	[15]
Total distance flown	17.0 km
Maximum altitude	24.0 m
Maximum groundspeed	10 m/s
Final flight	18 January 2024
Mission declared complete	25 January 2024

The program page carries the cumulative flight record the papers do not: 128.8 minutes aloft over 17.0 km, a maximum altitude of 24.0 m and a maximum groundspeed of 10 m/s across the 72 flights, with the mission declared complete on 25 January 2024, a week after the final flight on 18 January [15].

Flight in a thin atmosphere

Quantity	Earth	Mars
Density	1.225 kg/m³	0.017 kg/m³
Reference temperature	15 C	-50 C
Dynamic viscosity	1.75e-5 Ns/m²	1.13e-5 Ns/m²
Speed of sound	340.3 m/s	233.1 m/s
Tip speed at M = 0.7	238 m/s	163 m/s

Values from [11].

Density varies over 0.010 to 0.020 kg/m³ with ground elevation and with the yearly and daily cycle [11]. Two consequences follow, and they act against each other. Low density reduces the lift per unit blade area, which forces high tip speed and low vehicle mass. The low speed of sound, itself a consequence of a CO2 atmosphere at low temperature, caps the tip speed achievable at any given design Mach number.

The resulting blade sections operate at chord Reynolds numbers of 10,000 to 25,000, against order 10⁶ for terrestrial rotorcraft [11], [14]. Ingenuity’s own blade Reynolds number at 75 percent radius is 11,412. Below approximately Re = 100,000 the boundary layer can be subcritical [11], remaining laminar across the whole angle of attack range, which reduces maximum lift coefficient and raises drag coefficient by four to five times Earth values. The optimum airfoil shape in that regime differs from high-Reynolds practice: the flown CLF5605 section is 5 percent thick, and the ROAMX successor section is 1 percent thick [13].

Hover figure of merit against thrust coefficient

Hover figure of merit against thrust coefficient for the Ingenuity rotor, measured and predicted by CAMRAD II free wake (dashed), against a circular-arc plate rotor (solid), with the two sections at right. Peak figure of merit is approximately 0.63 inside a design thrust coefficient band of 0.015 to 0.020, against roughly 0.8 for a well-designed terrestrial rotor [11]. Public domain (NASA).

Rotor parameter	Value	Source
Airfoil, outboard	CLF5605, t/c 0.05, designed by AeroVironment	[2][13]
Thrust-weighted solidity	0.07391 per rotor, 0.148 for the coaxial pair	[4][12]
Tip speed at 2600 rpm	165 m/s	[2]
Tip Mach number	0.62 at the reference condition, held below 0.75	[2][3]
Design blade loading C_T/σ	0.10	[11]
Design thrust coefficient range	C_T 0.015 to 0.020	[2][11]
Peak hover figure of merit	approx 0.63, measured and calculated	[11]

Rotor performance was computed with CAMRAD II using a free wake for the coaxial pair and CFD-derived airfoil tables at 0.017 kg/m³ and -50 C, and agreed with measured performance [11]. Coaxial counter-rotation cancels torque without a tail rotor, which saves mass, at the cost of a trim problem: the two rotors must run at different collective settings, and the required difference is not monotonic in airspeed [2].

Differential collective against forward flight speed

Differential collective required to trim the coaxial rotor against forward flight speed, from two independent solvers. The required difference peaks near 5 to 10 m/s [2] where the upper rotor wake sweeps across the lower disk. Including the airframe changes the answer by roughly 0.2 degrees below 15 m/s. Source: [2]. Public domain (NASA).

Parametric work since the flight indicates the flown rotor is not near the optimum for the regime. Optimal solidity for a Mars rotor is approximately 0.3 in a six-bladed configuration, with peak figure of merit at blade loadings C_T/σ of 0.1 to 0.2 [12]. Wind tunnel measurement of the ROAMX successor airfoil at M = 0.60 and Re = 20,000, over angles of attack from -2.0 to 6.0 degrees, gives 25 percent higher lift-to-drag ratio at 75 percent radius than CLF5605, and a 29 percent higher rotor figure of merit [13], [14].

Power and energy

More than half of battery capacity is consumed by overnight survival heating rather than by flight [6]. Surface temperature at the vehicle ranges from -140 C to +30 C, with equatorial night reaching -80 C. A solar panel above the rotors, with approximately 0.04 m² of exposed area, recharges between sorties [9]. The energy scaling calibrated to the flight vehicle is E_sleep = 15 W^(1/3) Wh/sol, equivalent to P_sleep = 0.518 W^(1/3) W over a 1477 minute sol at 85 percent battery efficiency, where W is gross weight [11]. Sleep energy therefore grows as the cube root of vehicle mass while flight energy grows faster, which is why survival heating dominates at the 1.8 kg scale and not at the 18 kg scale of the proposed successors.

Motor efficiency, measured in flight

The two rotor motors are the same design and were matched on a dynamometer before integration. In forward flight on flights 14 to 16 at 2700 rpm the lower motor drew 117 W from the battery against 105 W for the upper at the same shaft power, which is 74 percent total electrical efficiency including commutation electronics and harness against 83 percent [20]. A commutation offset retune on sol 297 changed power by less than 1 W, which rules out commutation and leaves the cause unresolved. Nine points of efficiency between two nominally identical motors did not appear on the dynamometer and was found only by flying them, so a power budget that assumes paired-motor symmetry is assuming something this vehicle did not have.

Surviving the load shed

Below 15 V the power electronics shut down nearly all avionics including the battery heater and the FPGA, losing the clock and every wakeup alarm [20]. That happened. Over sols 426 to 429 [20] the aircraft’s components dropped to ambient Mars nighttime ground temperature, well below their designed operational range, for three consecutive nights; the radio link was re-established at 11:44 LMST on sol 429 and the downlinked data showed no evidence of hardware degradation. It is a single unplanned survival demonstration, not a qualification. The survival heater setpoint was walked from the default -15 C down to -20, then -25, then -28 C, saving roughly 4 Wh overnight per 5 C of setpoint reduction [20]. That saving is an energy balance model prediction used for operations planning rather than a measurement, and the floor is set by battery impedance, which rises sharply below -28 C.

Compute and avionics

Commercial smartphone-class processors were used rather than radiation-hardened parts, accepting higher single-event upset rates for greater processing capability. That capability is required because the one-way Earth-Mars light time is at least five minutes, so real-time piloting is impossible and each flight executes autonomously from an uploaded plan [8].

Element	Rate or specification	Source
Inertial measurement units	two, redundant	[8]
IMU raw acceleration / angular rate	1600 Hz / 3200 Hz
IMU rate into the filter after downsampling	500 Hz
Altimeter	50 Hz
Downward navigation camera	30 Hz
State estimator	Kalman filter over IMU, altimeter and camera
Motors	eight, four per rotor
Motor allocation per rotor	one holds rotation speed, three control blade pitch
Collective pitch range	-4.5 to +17.5 deg	[3]
Cyclic pitch range	±10 deg
Servo actuator bandwidth	12 Hz
Inner-loop crossover frequency	2.5 to 3 Hz

An inclinometer calibrates IMU biases before each flight [8]. The IMU chain filters, integrates, downsamples, applies bias corrections and buffers measurements for a state propagation process that runs between filter updates.

Autonomy

Navigation is dead reckoning on the inertial measurement units, corrected by tracking ground features. The camera designates certain frames as base frames, whose detected features become pseudo-landmarks; subsequent search frames are matched against those landmarks and the resulting visual shift corrects the accumulating dead reckoning drift [8]. A new base frame is generated when the maximum number of search frames since the last base frame is reached, or when the count of successfully tracked features drops. Over 200 s of flight the estimator drifted by under 1 m in position and under 40 cm/s in velocity [7].

Flight over featureless sand deprives the navigation camera of trackable features, which degrades the velocity estimate and therefore landing accuracy [8]. A hard landing on such terrain damaged the rotor blades in January 2024 and ended the mission after 72 flights [3].

Flight speed on Ingenuity was limited by the visual navigation system rather than by aerodynamics; successor design studies assume a navigation system supporting up to 50 m/s [11].

The laser altimeter has a known failure mode that is a sensor property rather than a flight rule: it does not return a valid range over certain metallic materials, and a bad value can trip fault protection into an immediate landing directly on the object [20]. It was handled operationally, by standoff distance and route planning, not by a fix.

Operations and results

Flights progressively expanded range and altitude, and the vehicle transitioned from technology demonstration to scout, imaging terrain ahead of Perseverance. Ambient winds during the first five flights ran 2 to 6 m/s at 1.5 m altitude as measured by MEDA on the rover, which sat within about 100 m during those flights [7].

Rotor speed was raised from 2537 to 2800 rpm for flights 14 to 24, sols 241 to 398, to carry the vehicle through the low atmospheric density of southern summer, and returned to 2537 rpm as density recovered [20]. 2800 rpm was above anything tested on Earth before flight, so it was qualified on Mars: a stationary high-speed spin on sol 204 followed by a two meter checkout flight.

Dust cost the vehicle both power and mechanism margin. During the sols 310 to 320 dust storm the Perseverance SkyCam measured a peak optical depth of 1.9, and Ingenuity’s solar array charge current at about 11:30 LTST fell from 296 mA on sol 302 to 221 mA on sol 316 before recovering to 302 mA, a 25 percent loss of charging current [20]. On sol 335 all six swashplate actuators failed their pre-flight self-test on an unallowable actuator load and flight 19 did not take off. A successful flight appeared to clear the mechanism, and the same failure recurred 25 sols later on sol 370 with no preceding dust event [20]. The diagnosis is from integrated motor currents, not from direct observation of the actuators.

Attitude telemetry from the flights was subsequently used as a wind instrument. A steady-state model converting yaw, pitch and roll into a wind vector, on the basis that the rotorcraft must tilt further into a stronger headwind, produced the first Martian wind measurements between 3 m and 24 m altitude [7]. For comparison, MEDA measured 3.2 ± 2.3 m/s at 1.5 m in northern spring and summer with 99 percent of values below 10 m/s, an afternoon peak of 6.1 ± 2.2 m/s, and ten-minute standard deviations of 0.57 ± 0.29 m/s at night against 1.85 ± 0.57 m/s by day. MEDA wind accuracy is 1 m/s below 10 m/s, 10 percent above, and 15 degrees in direction [7].

Electrostatic environment

Rotor blades charge triboelectrically against suspended grains, and the CO2 atmosphere at approximately 5 Torr breaks down at approximately 30 kV/m against approximately 3 MV/m at Earth sea level [9]. Townsend dark discharge begins above 20 kV/m and spark discharge near 50 kV/m, with a primary ionization coefficient of order 1e4 /m, a Townsend parameter of approximately 285 kV/m, and a secondary-to-primary ionization ratio of 0.01 to 0.02. At 2800 rpm the blades sweep approximately 290 revolutions per second through the near field [9]. In an ambient dust load, current balance and charge dissipation back into the atmosphere proceed without breakdown; inside a rotor-created particulate cloud the tribocharging current can be large enough to stimulate local breakdown near the vehicle.

Successor designs

Concept	Gross weight	Rotor radius	Solidity	Rotor speed	Disk loading	FM	Source
Ingenuity	1.8 kg	0.605 m	0.148 (coaxial pair)	2600 rpm		approx 0.63	[11][4]
MSH coaxial	18.032 kg	1.25 m	0.310	1247 rpm	3.67 kg/m²	0.675	[11]
MSH hexacopter	17.662 kg	0.64 m (six rotors)	0.193	2435 rpm	2.29 kg/m²	0.615
Sample Recovery Helicopter		0.700 m	0.06412 per rotor	2350 rpm			[4]

The Mars Science Helicopter design mission is 30 s of takeoff at hover power, a climb to 200 m, a 1 km cruise to the science site, a 2 minute hover, landing, one sol of sleep and recharge, with the battery sized to that energy plus a 20 percent reserve [11]. Payload is 2.02 kg at 35 W of equipment power, with 1.2 kg of avionics including 0.1 kg of telecom. Design blade loading is C_T/σ = 0.11 [11], 10 percent above Ingenuity’s, justified by the measured rotor thrust capability and the expected gain from a circular-arc airfoil. Hover tip Mach number is 0.7 for a tip speed of 163.2 m/s, and cruise is 30 m/s, the minimum power speed, giving an advance ratio of 0.18 and an advancing tip Mach number of 0.83 [11]. Blade Reynolds numbers at 75 percent radius rise to 24,752 for the coaxial and 15,784 for the hexacopter, against 11,412 for Ingenuity. Aeroelastic stability for these rotors has been swept across densities of 0.013 and 0.020 kg/m³ and tip Mach numbers of 0.4 to 0.9 [4].

Technologies developed

Ingenuity established that a rotor sized to a 0.017 kg/m³ atmosphere and a Reynolds number of order 10⁴ can be flown, controlled and navigated without ground intervention, and produced flight data against which CAMRAD II free-wake predictions and airfoil tables were validated [11], [2]. In-flight system identification over 0.15 to 8 Hz gave a control model derived from the vehicle itself rather than from ground testing [3].

Its use of commercial smartphone-class processors moved a class of avionics from prohibited to demonstrated. Its attitude telemetry became an atmospheric instrument, delivering the first wind profiles between 3 m and 24 m on Mars [7]. And its measured rotor performance is the baseline against which the ROAMX airfoil and blade work claims a 29 percent figure of merit improvement, which is the difference between a technology demonstration and a vehicle with useful range [14].

References

Afman, J. P., Feron, E. and Walker, M. (2019). A full scale atmospheric flight experimental research environment for the Mars helicopter . arXiv preprint. Source

BibTeX

@article{afman2019full,
  title = {A full scale atmospheric flight experimental research environment for the Mars helicopter},
  author = {Afman, J. Pablo and Feron, Eric and Walker, Mitchell},
  journal = {arXiv preprint},
  year = {2019},
  url = {https://arxiv.org/abs/1910.09290}
}

Balaram, J. (., Canham, T., Duncan, C., Golombek, M., Grip, H. F., Johnson, W., Maki, J., Quon, A., Stern, R. and Zhu, D. (2018). Mars Helicopter Technology Demonstrator . AIAA Atmospheric Flight Mechanics Conference, AIAA 2018-0023. Source

BibTeX

@inproceedings{balaram2018marshelicopter,
  title = {Mars Helicopter Technology Demonstrator},
  author = {Balaram, J. (Bob) and Canham, Timothy and Duncan, Courtney and Golombek, Matt and Grip, Håvard F. and Johnson, Wayne and Maki, Justin and Quon, Amelia and Stern, Ryan and Zhu, David},
  booktitle = {AIAA Atmospheric Flight Mechanics Conference},
  number = {AIAA 2018-0023},
  publisher = {American Institute of Aeronautics and Astronautics},
  address = {Kissimmee, Florida},
  year = {2018},
  doi = {10.2514/6.2018-0023}
}

Dull, C., Wagner, L., Young, L. and Johnson, W. (2022). Hover and Forward Flight Performance Modeling of the Ingenuity Mars Helicopter . Aeromechanics for Advanced Vertical Flight Technical Meeting, 20210026235. Source

BibTeX

@inproceedings{dull2022hover,
  title = {Hover and Forward Flight Performance Modeling of the Ingenuity Mars Helicopter},
  author = {Dull, Cuyler and Wagner, Lauren and Young, Larry and Johnson, Wayne},
  booktitle = {Aeromechanics for Advanced Vertical Flight Technical Meeting},
  number = {20210026235},
  institution = {NASA},
  address = {San Jose, CA},
  year = {2022},
  url = {https://ntrs.nasa.gov/citations/20210026235},
  abstract = {In 2015, NASA’s Jet Propulsion Laboratory partnered with Ames Research Center, Langley Research Center, and AeroVironment to develop Ingenuity, a small coaxial helicopter capable of flying within Mars’ unique atmospheric conditions. Ingenuity was successfully deployed from its protective shroud on the underside of the Mars 2020 Perseverance Rover and has flown 17 flights on Mars as of December 2021. A number of rotorcraft analysis tools were utilized, and a series of experimental tests were performed to ready Ingenuity for its launch with the Perseverance Rover in July 2020. In this paper, RotCFD, a Reynolds-averaged Navier-Stokes flow solver, is used to model Ingenuity in hover and forward flight for the purposes of validating tools to aid in the development of a future generation of Mars rotorcraft. The results from the RotCFD modeling are benchmarked against results from hover performance tests of the Ingenuity prototype in the 25-Foot Space Simulator at the Jet Propulsion Laboratory and are also compared to hover and forward flight predictions made by CAMRAD II, a well-known comprehensive rotorcraft analysis code. Surrogate performance models are trained to obtain a set of trimmed rotor settings for Ingenuity at different forward flight speeds, which are then used as inputs for the RotCFD forward flight simulations. Additionally, a study of the airframe-rotor interaction and a study of the aerodynamics of the individual airframe components of Ingenuity in forward flight are performed. Finally, to better understand performance predictions by RotCFD and CAMRAD II, a study is conducted on how sectional angles of attack in each code vary with radial station and azimuth. }
}

Jackson, B., Fenton, L., Brown, T., Munguira, A., Martinez, G., Newman, C., Viúdez-Moreiras, D., Golombek, M., Lorenz, R., Paton, M. D. and Conway, D. (2024). Profiling Near-Surface Winds on Mars Using Attitude Data from Mars 2020 Ingenuity . The Planetary Science Journal. Source

BibTeX

@article{jackson2024profiling,
  title = {Profiling Near-Surface Winds on Mars Using Attitude Data from Mars 2020 Ingenuity},
  author = {Jackson, Brian and Fenton, Lori and Brown, Travis and Munguira, Asier and Martinez, German and Newman, Claire and Viúdez-Moreiras, Daniel and Golombek, Matthew and Lorenz, Ralph and Paton, Mark D. and Conway, Dylan},
  journal = {The Planetary Science Journal},
  volume = {6},
  pages = {21},
  year = {2024},
  doi = {10.3847/psj/ad8b41},
  abstract = {Abstract We used attitude data from the Mars Ingenuity helicopter with a simple steady-state model to estimate wind speeds and directions at altitudes between 3 and 24 m, the first time winds at such altitudes have been probed on Mars. We compared our estimates to wind data from the meteorology package MEDA on board the Mars 2020 Perseverance rover and to predictions from meteorological models. Wind directions inferred from Ingenuity data agreed with the directions measured by MEDA, when the latter were available, but deviated from model-predicted directions by as much as 180° in some cases. The inferred wind speeds are often much higher than expected. For example, meteorological predictions suggest that Ingenuity should not have seen wind speeds above about 15 m s −1 during its 59th flight, but we inferred speeds reaching nearly 25 m s −1 . For flights during which we have MEDA data to compare to, inferred wind speeds imply friction velocities &gt;1 m s −1 and roughness lengths &gt;10 cm, which seem implausibly large. These results suggest that Ingenuity was probing winds sensitive to aerodynamic conditions hundreds of meters upwind instead of the conditions very near Mars 2020, but they may also reflect a need for updated boundary layer wind models. An improved model for Ingenuity’s aerodynamic response that includes the effects of transient winds may also modify our results. In any case, the work here provides a foundation for exploration of planetary boundary layers using drones and suggests important future avenues for research and development.}
}

Johnson, W., Withrow-Maser, S., Young, L., Malpica, C., Koning, W. J. F., Kuang, W., Fehler, M., Tuano, A., Chan, A., Datta, A., Chi, C., Lumba, R., Escobar, D., Balaram, J., Tzanetos, T. and Grip, H. F. (2020). Mars Science Helicopter Conceptual Design . ASCEND, NASA/TM-2020-220485. Source

BibTeX

@inproceedings{johnson2020mars,
  title = {Mars Science Helicopter Conceptual Design},
  author = {Johnson, Wayne and Withrow-Maser, Shannah and Young, L. and Malpica, Carlos and Koning, Witold J. F. and Kuang, W. and Fehler, M. and Tuano, A. and Chan, Athena and Datta, A. and Chi, C. and Lumba, R. and Escobar, D. and Balaram, J. and Tzanetos, T. and Grip, H. F.},
  booktitle = {ASCEND},
  number = {NASA/TM-2020-220485},
  institution = {NASA Ames Research Center},
  year = {2020},
  doi = {10.2514/6.2020-4029},
  abstract = {Robotic planetary aerial vehicles increase the range of terrain that can be examined, compared to traditional landers and rovers, and have more near-surface capability than orbiters. Aerial mobility is a promising possibility for planetary exploration as it reduces the challenges that difficult obstacles pose to ground vehicles. The first use of a rotorcraft for a planetary mission will be in 2021, when the Ingenuity Mars helicopter technology demonstrator will be deployed via the Perseverance rover. NASA’s Jet Propulsion Laboratory and NASA Ames Research Center are exploring possibilities for a Mars Science Helicopter, a second-generation Mars rotorcraft with the capability of conducting science investigations independently of a lander or rover (although this type of vehicle could also be used to assist rovers or landers in future missions). Two, large rotorcraft configurations are described: a hexacopter and a co-axial helicopter with a payload in the range of two to three kilograms and an overall vehicle mass of approximately twenty kilograms. Additionally, advancements in technology over the course of the study are applied to a rotorcraft of the same size and form as Ingenuity. Initial estimates of weight and performance were based on the capabilities of Ingenuity. Rotorcraft designs for Mars are constrained by the dimensions of the aeroshell and lander for the trip to the planet, constraining maximum rotor dimensions and, hence, overall performance potential. The effects of airfoils designed specifically for the low Reynolds number and high Mach number inherent to operation on Mars were studied. Rotor structural designs were developed that met blade frequency and weight targets, subject to material stress limits. The final designs are representative of the vehicle configurations required for a large range of future missions and will require relatively minor adaptations once science tasks are chosen. These designs will be compared to Ingenuity to demonstrate technology advancements developed during the study.}
}

Koning, W. J. F., Romander, E. A. and Johnson, W. (2018). Low Reynolds Number Airfoil Evaluation for the Mars Helicopter Rotor . American Helicopter Society Annual Forum. Source

BibTeX

@inproceedings{koning2018low,
  title = {Low Reynolds Number Airfoil Evaluation for the Mars Helicopter Rotor},
  author = {Koning, Witold J. F. and Romander, Ethan A. and Johnson, Wayne},
  booktitle = {American Helicopter Society Annual Forum},
  pages = {1-17},
  publisher = {NASA Technical Reports Server},
  year = {2018},
  doi = {10.4050/f-0074-2018-12679},
  abstract = {The present research provides a performance comparison between several low Reynolds number airfoil profiles for the Mars Helicopter. The low density of the Martian atmosphere and the relatively small Mars Helicopter rotor result in very low chord-based Reynolds number flows, Re𝒸 = O(10³ - 10⁴). At low Reynolds numbers, flat and cambered plates can out-perform conventional airfoils, making them of interest for the Mars Helicopter rotor. Performance models are generated for the Mars Helicopter rotor based on a free wake analysis, and the results are compared with Mars Helicopter isolated rotor performance from previous work. A Reynolds-Averaged Navier-Stokes based approach is used to generate the airfoil deck using OVERFLOW. The model is constructed using airfoil data tables (C81 files) that are used by the comprehensive rotor analysis code CAMRADII. Performance results for the Martian atmosphere show improved performance for the cambered plate rotor over conventional airfoils, in terms of thrust for equal power and Figure of Merit for equal blade loading. The cambered flat plate airfoil produces 7% larger maximum rotor thrust versus the Mars Helicopter airfoils, and 5% larger Figure of Merit over the design thrust coefficient range. Larger maximum thrust allows an increase of design blade loading for the same thrust range for control authority, whereas the larger Figure of Merit reduces power requirements.}
}

Koning, W. J. F., Perez Perez, N., Cummings, H. V., Nagata, T., Kanzaki, Y., Kasai, M., Miyagi, M., Nonomura, T., Asai, K., Caros, L., Buxton, O. and Vincent, P. (2024). Experimental Results for Mars Rotorcraft Airfoils (roamx-0201 and clf5605) at Low Reynolds Number and Compressible Flow in a Mars Wind Tunnel . NASA Ames Research Center, NASA/TM-20240004230. Source

BibTeX

@techreport{koning2024experimental,
  title = {Experimental Results for Mars Rotorcraft Airfoils (roamx-0201 and clf5605) at Low Reynolds Number and Compressible Flow in a Mars Wind Tunnel},
  author = {Koning, Witold J. F. and Perez Perez, N. and Cummings, H. V. and Nagata, Taiichi and Kanzaki, Y. and Kasai, M. and Miyagi, M. and Nonomura, T. and Asai, K. and Caros, L. and Buxton, O. and Vincent, P.},
  number = {NASA/TM-20240004230},
  institution = {NASA Ames Research Center},
  year = {2024},
  url = {https://ntrs.nasa.gov/citations/20240004230},
  abstract = {Experimental results are obtained for a roamx-0201 type airfoil and the clf5605 airfoil at highsubsonic, low Reynolds number conditions using the Tohoku University Mars Wind Tunnel, Japan. The tests are conducted at a Mach number of M = 0.60, and a Reynolds number of Re = 20,000 to reflect representative aerodynamics of a rotor blade for Mars exploration. The angle of attack is varied between α = −2.0 deg and α = 6.0 deg. The roamx-0201 type airfoil is an unconventional airfoil optimized for the chosen tunnel operating conditions using the Evolutionary aLgorithm for Iterative Studies of Aeromechanics (ELISA), developed under the Rotor Optimization for the Advancement of Mars eXploration (ROAMX) project. ELISA is utilized here to optimize aerodynamic airfoil performance using a Genetic Algorithm and two-dimensional high-fidelity CFD simulations, ultimately resulting in a Pareto-optimal airfoil set. The clf5605 airfoil is the outboard airfoil used on the Ingenuity Mars Helicopter and provides a baseline against which the roamx-0201, as well as possible future airfoil profiles for the compressible low Reynolds number regime, can be compared against. Lift and drag data are recorded using a balance, pressure distributions are obtained using Pressure Sensitive Paint (PSP) application, and Schlieren images are obtained to visualize the flowfield. The data is tabulated to aid future research.}
}

Perez Perez, B. N., Cummings, H. V., Koning, W. J. F., Haddad, F. B., Romander, E. A., Johnson, W., Datta, A., Nagata, T., Asai, K., Nonomura, T., Caros Roca, L., Buxton, O. and Vincent, P. (2025). Novel Guidelines and Designs for Airfoils and Helicopter Blades for Mars Applications With Experimental Validation . AIAA Sci Tech Forum. Source

BibTeX

@inproceedings{perezperez2025novel,
  title = {Novel Guidelines and Designs for Airfoils and Helicopter Blades for Mars Applications With Experimental Validation},
  author = {Perez Perez, B. N. and Cummings, H. V. and Koning, Witold J. F. and Haddad, F. B. and Romander, Ethan A. and Johnson, Wayne and Datta, A. and Nagata, Taiichi and Asai, K. and Nonomura, T. and Caros Roca, L. and Buxton, O. and Vincent, P.},
  booktitle = {AIAA Sci Tech Forum},
  institution = {NASA Ames Research Center},
  address = {Orlando, Florida},
  year = {2025},
  url = {https://ntrs.nasa.gov/citations/20250010782},
  abstract = {The Rotor Optimization for the Advancement of Mars eXploration (ROAMX) project advances the design and validation of airfoils and blades for next-generation Mars rotorcraft. A comprehensive computational modeling and experimental campaign was conducted to address the unique low-density flight environment of Mars. An airfoil and rotor modeling and optimization framework tailored to Mars Reynolds and Mach number regimes was developed and applied to generate a portfolio of candidate geometries. A novel lift-generation mechanism was identified and experimentally validated, broadening the design space for airfoil and rotor performance. Airfoil performance was rigorously assessed through a combination of wind tunnel testing and high-fidelity computational fluid dynamics simulations under Mars representative flow conditions. Airfoil optimization resulted in airfoils that had a 25% increase in coefficient lift to drag ratio at the 75% radial station, compared to the clf5605 baseline airfoil (Ingenuity Mars Helicopter). A structural design methodology for Mars rotor blades was established and the strength of the rotor blades was verified via static pull testing at 110% of the centrifugal force experienced at a tip Mach number of 0.95. Facility enhancements at NASA Ames further expanded Mars rotorcraft testing capabilities, including the development of a state-of-the-art hover stand capable of high-accuracy performance measurements at very low pressure. Collectively, these efforts culminated in the demonstration of optimized rotor performance at Mars flight conditions, providing validated design tools, test infrastructure, and performance data to support future scientific and exploration rotorcraft missions on Mars. The full-scale ROAMX optimized rotor was tested and achieved a 29% increase in peak Figure of Merit, compared to the Ingenuity helicopter rotor, at the design density.}
}

Radotich, M., Withrow-Maser, S., deSouza, Z., Gelhar, S. and Gallagher, H. (2021). A Study of Past, Present, and Future Mars Rotorcraft . Biennial Autonomous VTOL Technical Meeting, 20210000448. Source

BibTeX

@inproceedings{radotich2021study,
  title = {A Study of Past, Present, and Future Mars Rotorcraft},
  author = {Radotich, Michael and Withrow-Maser, Shannah and deSouza, Zarya and Gelhar, Sophie and Gallagher, Henry},
  booktitle = {Biennial Autonomous VTOL Technical Meeting},
  number = {20210000448},
  institution = {NASA},
  year = {2021},
  url = {https://ntrs.nasa.gov/citations/20210000448},
  abstract = {Interest in utilizing rotorcraft to explore Mars is expected to increase following the anticipated successful technical demonstration of the Mars Helicopter, Ingenuity, during the Mars 2020 mission. Previously, science investigations have been limited by either the instrumentation resolution on orbiters or the roughness/accessibility of terrain a rover can traverse. Rotorcraft can enable low-altitude flight over and on-surface exploration at previously inaccessible locations. This paper describes potential mission concepts designed to utilize the unique capabilities of rotorcraft to advance the science performed in extraterrestrial environments. This includes missions tailored for investigating if Mars ever supported life, understanding climate processes and history, determining the evolution of Martian geology, and preparing for human exploration. The Mars rotorcraft mission concepts described in this paper can be divided into two categories: rover-assisted missions and independent (rotorcraft-only) missions. A number of concept vehicles, consistent with these proposed missions, are also discussed.}
}

Roumage, G., Azaiez, S., Faure, C. and Louise, S. (2025). The Ingenuity Mars Helicopter Specified and Analyzed with the Real-time Mode-aware Dataflow Model . arXiv preprint. Source

BibTeX

@article{roumage2025ingenuity,
  title = {The Ingenuity Mars Helicopter Specified and Analyzed with the Real-time Mode-aware Dataflow Model},
  author = {Roumage, Guillaume and Azaiez, Selma and Faure, Cyril and Louise, Stéphane},
  journal = {arXiv preprint},
  year = {2025},
  doi = {10.32388/zn8rvc},
  abstract = {Ingenuity is an autonomous Cyber-Pysical System (CPS) that has successfully completed more than 70 flights over Mars between 2021 and 2024. Ensuring the safety of its mission is paramount, as any failure could result in catastrophic economic damage and significant financial losses. Dataflow Models of Computation and Communication (DF MoCCs) serve as a formal framework for specifying and analyzing the timing behavior of such CPSs. In particular, the Real-time Mode-aware Dataflow (RMDF) model is highly suitable to specify and analyze real-time and mode-dependent CPSs like Ingenuity. This paper showcases the application of RMDF for the specification and analysis of Ingenuity. We propose a dataflow specification of Ingenuity, analyze its timing behavior, and provide a feasibility test. Finally, we proposed a plausible explanation of the timing anomaly that occurred during the sixth flight of Ingenuity.}
}

Sahragard-Monfared, G., Bowman, J., Koning, W. J. F. and Johnson, W. (2025). Effects of Solidity, Number of Blades, and Chord Distribution on Rotor Performance in a Martian Environment . Vertical Flight Society Annual Forum and Technology Display. Source

BibTeX

@inproceedings{sahragardmonfared2025effects,
  title = {Effects of Solidity, Number of Blades, and Chord Distribution on Rotor Performance in a Martian Environment},
  author = {Sahragard-Monfared, Gianmarco and Bowman, Joshua and Koning, Witold J. F. and Johnson, Wayne},
  booktitle = {Vertical Flight Society Annual Forum and Technology Display},
  pages = {1-8},
  institution = {NASA Ames Research Center},
  year = {2025},
  doi = {10.4050/f-0081-2025-0354},
  abstract = {Rotor performance in a Martian environment was analyzed with an objective of increasing thrust with minimal impact on efficiency. The Sample Recovery Helicopter (SRH) and Rotorcraft Optimization for the Advancement of Mars Exploration (ROAMX) rotors were studied by varying solidity, blade count, and chord distribution to determine which configuration delivered the most desirable performance. For all configurations, the ROAMX rotor displayed better performance than the SRH rotor. It was observed that increasing solidity reduced the blade loading required to achieve the peak figure of merit, and beyond a solidity ratio of 0.3 the figure of merit was negatively impacted. For both rotors a 6-bladed configuration with a solidity ratio of 0.3 delivered the optimal figure of merit.}
}

Veismann, M., Yos, D. and Gharib, M. (2022). Parametric Study of Small-Scale Rotors in Axial Descent . Physics of Fluids, 3. Source

BibTeX

@article{veismann2022parametric,
  title = {Parametric Study of Small-Scale Rotors in Axial Descent},
  author = {Veismann, Marcel and Yos, Daniel and Gharib, Morteza},
  journal = {Physics of Fluids},
  volume = {34},
  number = {3},
  pages = {035124},
  year = {2022},
  doi = {10.1063/5.0083761},
  abstract = {Despite extensive research in multirotor aerodynamics in the recent past, axial descent, specifically the vortex ring state, still poses great challenges for multirotor configurations as this flight stage is typically accompanied by severe losses in rotor thrust and strong thrust fluctuations. This paper presents a parametric study to investigate the influence of relevant geometric parameters of a small-scale rotor blade on the rotor performance in axial descent. Design variables subject to variation were the collective pitch, chord length, taper ratio, number of blades, as well as the tip geometry. Custom rotors for each parameter modification were manufactured and experimentally evaluated in wind tunnel tests with mean thrust recordings and measurements of the thrust fluctuations serving as performance metrics. Results indicated that rotor blades with larger aspect ratio and higher blade loading coefficient are less affected by the adverse aerodynamics in the vortex ring state, experiencing lower thrust losses and vibrational loads. Particle image velocimetry flow visualization confirmed that the aerodynamic losses in the vortex ring state can be attributed to blade vortex interactions. Comparison of the rotor flow structure in hover of all investigated rotor designs suggested that improvements in the descent performance of a rotor stem from a combination of reduced tip vortex strength and increased axial tip vortex convection rate. Using the experimental findings of this study, a predictive model for approximating the maximum extent of mean thrust losses in axial descent for a given blade geometry and hover thrust coefficient could be established.}
}

Ingenuity

Overview

Specifications

Mission profile

Flight in a thin atmosphere

Power and energy

Motor efficiency, measured in flight

Surviving the load shed

Compute and avionics

Autonomy

Operations and results

Electrostatic environment

Successor designs

Technologies developed

References

Further reading