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Michelle Dominguez

Publications and source records attributed to Michelle Dominguez.

Mars Science Helicopter Rotor Geometry

The Jet Propulsion Laboratory and NASA Ames Research Center are exploring possibilities for a Mars Science Helicopter (MSH), a second-generation Mars rotorcraft designed to conduct science investigations independently of a lander or rover. The goal of the MSH concept design is to establish the feasibility of flying a larger, more capable rotorcraft on Mars, with a payload of two to three kg and an overall vehicle mass of approximately twenty kg. This report documents the geometry (including planform, twist, and airfoils) of the MSH (hexacopter configuration) rotor, for use in future research on rotor performance in the Mars atmosphere.

Mars

Airfoil Table Modification for Improved Calculation of Ingenuity Rotor Performance

To better characterize the behavior of the Ingenuity helicopter, multiple test campaigns were conducted. These tests included the Engineering Design Model 1 (EDM1) tests and the Transonic Rotor Test (TRT), both of which assessed Ingenuity rotor performance at various conditions. Using a comprehensive rotorcraft analysis tool, CAMRAD II, test setups of the two different Ingenuity test campaigns were simulated. The EDM1 test used coaxial test stand which focused on varying collective at various feasible Martian atmospheric densities and the TRT test used a single rotor test stand which focused on varying RPM to assess performance at different blade tip Mach numbers. Initial CAMRAD II analyses yielded performance results which differed significantly from experimental results. To reconcile the experimental results and the CAMRAD II analyses, modifications were made to the input airfoil decks for CAMRAD II. After several iterations of modifications, a specific method of modification was found that more accurately predicted experimental behavior at all tested densities for the coaxial rotor. This same modification was less successful for the single rotor test results. There are a number of differences between coaxial and single rotor aerodynamics and between the two test stands (hub and control system); also, there is a small influence of RPM (mainly tip Mach number) on dimensionless performance. These differences may be causing the coaxial rotor modifications not being successful for the single rotor.

Airfoil

Mars Helicopter Ingenuity Rotor Geometry

The NASA Mars Helicopter Ingenuity performed its maiden flight on April 19, 2021, and opened new possibilities for planetary exploration. Ingenuity has ended its mission after experiencing an anomaly during its 72nd flight on January 18, 2024. Due to the low density and low temperature of the surface atmosphere on Mars, significant challenges must be overcome to achieve aerodynamic performance. The low density of the Martian atmosphere and the relatively small-scale rotor result in flows with very low Reynolds number, reducing the lifting force and lifting efficiency, respectively. Until recently, compressible flow at Reynolds numbers around Re = 10,000 was of moderate practical interest but with the success of Ingenuity, the aerodynamic regime is appreciating considerable attention. The purpose of this report is to document the geometry (planform, twist, and airfoils) of the Mars Helicopter rotor, for use in future research on rotor performance in the Mars atmosphere.

Mars

XV-15 Tilt Rotor Research Aircraft Photogrammetry and Metrology Measurement

A new measurement capability was created by combining photogrammetry and metrology techniques to accurately measure one half of the XV-15 Tilt Rotor Research Aircraft at the Smithsonian’s Udvar-Hazy museum. The challenges imposed by the fuselage and surrounding environment at Udvar-Hazy were overcome by careful application of photogrammetry and metrology techniques. Data analyses and processing included the use of multiple reverse engineering programs to accurately generate a complete 3-dimensional water-tight geometry of the aircraft and rotor blade. This paper describes the photogrammetry and metrology measurement systems, technology and hardware set-up, data analysis and processing methods, future work, and lessons learned. In addition, selected measurement results of the fuselage and rotor blade are presented.

XV-15

LILI (Long-term Ice-field Levitating Investigator): Mars Aerial and Ground Explorer for Martian Polar Regions

Exploration of Mars is currently underway by use of a rover and helicopter team. A hybrid ground/aerial vehicle concept that marries the respective strengths of rovers and rotorcraft for Mars exploration is presented in this paper. LILI (Long-term Ice-field Levitating Investigator) is a novel hybrid ground- and aerial-mobility concept vehicle proposed for exploration of the Martian polar regions. LILI combines episodic rotary-wing flight with primary ground-mobility-mode of a propeller-driven sled via an arrangement of three skis/runners and tilting proprotors. In this manner, the best of both worlds can be achieved for Mars polar exploration: rapid, obstacle-bypassing flight with low-power, efficient, longer duration -- and range -- sledding. LILI’s propulsion system is based on solar-electric recharging of batteries. Consequently, periods of its air or ground movement are separated by periods of recharging. The overall project goal is to refine the vehicle and mission concept, while constrained within the current technology state of the art, and, leveraging the design heritage of the Ingenuity Mars Helicopter technology demonstrator. LILI’s aerodynamic performance, flow interactions, and design characteristics, as well as potential mission profiles are suggested.

LILI

Fundamental Test of a Hovering Rotor: Comprehensive Measurements for CFD Validation

A model-scale hover test of a 4-bladed, 11.08-ft diameter rotor was recently completed inside the National Full-Scale Aerodynamics Complex 80- by 120-Foot Wind Tunnel test section. The primary objective of the test was to acquire key experimental data for a hovering rotor of sufficient quality and quantity to allow validation of state-of-the-art analysis codes. A comprehensive measurement set has been acquired, including rotor performance, blade airloads, flow transition locations, blade deflections, and wake geometry for a range of tip Mach numbers and collective settings. The present paper provides an overview of the test, including detailed descriptions of the hardware, instrumentation, and measurement systems. In addition, the specific test objectives, approach, and sample results are presented. The full test database, as well as detailed rotor geometry information, will ultimately be shared openly on a NASA-sponsored website to serve as a benchmark validation dataset.

Hover

PlanetarY Telemetric Helicopter for Investigation and Analysis (PYTHIA): A Rotorcraft for Martian Lava Tube Exploration

The PlanetarY Telemetric Helicopter for Investigation and Analysis (PYTHIA) project presents an early feasibility study into future Mars rotorcraft. With the success of Ingenuity and the current development of the Mars Sample Retrieval Helicopters, there is motivation to explore additional vehicle concepts for Mars exploration. This work presents an early conceptual design of a lava tube exploring quadrotor. The nominal mission for the PYTHIA quadrotor includes a two-phase in-depth exploration of one or mutliple lava tubes in the area of interest, Arsia Mons. A sizing analysis was completed using the NASA Design and Analysis of Rotorcraft (NDARC) tool. An eight-bladed quadrotor was selected based on the NDARC sizing sweeps. With preliminary vehicle and blade sizing completed, a flow visualization study was conducted. Two simulations were completed in Rotorcraft Computational Fluid Dynamics (RotCFD): one of the quadrotor alone and another in a lava tube. This paper introduces a baseline reference mission, preliminary vehicle design, and initial sizing analysis of a rotorcraft to explore Martian lava tubes.

PlanetarY