Search NASA⌕ Search

Engineering topics

Natasha Schatzman

Publications and source records attributed to Natasha Schatzman.

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↗

Acoustics Technical Working Group and UAM Noise Working Group Proceedings

The NASA Acoustics Technical Working Group Meeting originally started as a program planning meeting in 1992 and has grown through the years. The purpose of these biannual meetings is to foster communication and collaboration among NASA researchers and their university, industry, and government colleagues on activities and work of current and future mutual interest. The NASA-led Urban Air Mobility (UAM) Noise Working Group (UNWG) Meeting began in 2018 as a one-day meeting immediately following the Acoustics Technical Working Group Meeting. The UNWG utilizes four subgroups that conduct regular meetings throughout the year to focus on challenges facing UAM vehicles for community noise and acceptance. The four subgroups coordinate research for development of noise prediction tools/noise reduction technologies, ground and flight test methods, human response and metrics, and regulations and policy (led by the FAA). This work is a compilation of the presentations given at ATWG/UNWG Fall 2022 held in person and via Teams at NASA Glenn Research Center. All NASA content was previously submitted through STRIVES for public presentation. This is merely a compilation. Non-NASA content has permission to distribute. Slide 208 video is included in the Available Downloads as Medial.MOV.

Advanced Air Mobility↗

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↗

RABBIT: A Rapid Low Fidelity BVI Prediction Tool—Comparison and Validation using the NASA RVLT Toolchain

Rotorcraft noise source identification is at the forefront of civil rotorcraft applications with the emergence of the Urban Air Mobility (UAM) market. Blade Vortex Interaction (BVI) has been identified as one key source of noise produced by a rotor. To predict BVI occurrences for various Urban Air Mobility (UAM) configurations, the RApid Blade and Blade-Vortex InTeraction (RABBIT) tool was developed and utilized. The tool is built from a Beddoes Wake Model, and computes variables such as miss distance and BVI angle to calculate an impulse factor, which is able to visualize BVI for a given vehicle and flight condition. A complete checkout of this tool and comparison with CAMRADII and ANOPP2/AARON, is performed. A wake comparison between RABBIT and CAMRADII is presented, and BVI is compared with ANOPP2/AARON’s acoustic pressure time history to verify the tools effectiveness and accuracy. Three NASA Revolutionary Vertical Lift Technology (RVLT) concept vehicles were analyzed with increasing geometric and aerodynamic complexity, including the Quiet Single Main Rotor (QSMR), Side-by-Side, and Quadrotor. An analysis of the results concludes that RABBIT presents a low-fidelity tool that accurately predicts BVI location and intensity for multiple vehicle configurations and various flight conditions.

RABBIT↗

Mars Sample Recovery Helicopter: Rotorcraft to Retrieve the First Samples from the Martian Surface

The Mars Sample Return Mission (MSR) will carry the next set of Mars helicopters, Sample Recovery Helicopters (SRHs), to the Martian surface. After successfully demonstrating extraterrestrial flight in 2021, Ingenuity has acted as a “scout” for the Perseverance rover while the rover gathers samples of Martian soil. In 2028, the MSR mission will launch a lander and two Ingenuity-sized SRHs to retrieve these samples. These will be the first samples of the Martian surface delivered to Earth. The SRH project will maintain heritage from Ingenuity’s design when possible. However, several key changes must be made, including a ground mobility system, a robotic arm for tube manipulation, and the ability to carry the weight of a science payload (the sample tubes). In addition, the onboard software and cameras will be upgraded, and the rotor radius will be increased. Furthermore, new rotor performance and flight dynamics models and thorough characterization of vehicle limits will be required. The new vehicle design will be described, as well as validation and verification efforts to date.

Rotorcraft↗

Best Practices for Predicting Acoustics of a Single Rotor Using the NASA RVLT Conceptual Design Toolchain

To facilitate the development of the Urban Air Mobility (UAM) market, the NASA Revolutionary Vertical Lift Technology Project has created the Conceptual Design Toolchain, a suite of tools developed and/or selected to assist rotorcraft designers in all stages of rotorcraft design. Of particular interest to the UAM noise community are the following two steps in this toolchain: comprehensive analysis and acoustic prediction. Since the UAM application is relatively new, there is a need for a systematic study on how best to utilize these codes. To this end, the current study documents best practices for using the comprehensive analysis codes, CAMRAD II and CHARM, along with the acoustic code AARON. Two single rotors are considered: i) a simple rotor and ii) a rotor that is more exemplary of what UAM designers might use. Best practices are presented for the prediction of both tonal and broadband self-noise, along with the corresponding results. The goal is to provide conceptual designers the tools to conduct accurate noise prediction using the RVLT Conceptual Design Toolchain.

Acoustics↗

Data Processing and Analysis of Performance Measurements From Ingenuity Rotors in the Jet Propulsion Laboratory 25-Ft Space Simulator

The success of Ingenuity completing over 71 flights on Mars has resulted in the possible use of two further optimized Ingenuity-sized helicopters to retrieve samples for the planned Mars Sample Return campaign. Data to validate performance for several rotor speeds, densities, configurations, and collectives will aid in the design process and help in understanding Ingenuity’s current performance limitations. Tests were performed at the Jet Propulsion Laboratory (JPL) in the 25-foot Space Simulator, which include the Engineering Design Model 1 (EDM-1) with and without a cruciform box, and the Transonic Rotor Test (TRT) which is a single rotor setup featuring the same blade geometry as EDM-1 but designed to spin at much higher RPMs. The experimental setup, test matrix, data processing, data quality, and the performance results for EDM1 and TRT campaigns are presented.

Processing↗

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↗

Performance Analysis and Data Processing for the Mars Sample Recovery Helicopter in the Jet Propulsion Laboratory 25-ft Space Simulator

On April 19, 2021, Ingenuity became the first helicopter to fly on Mars at Jezero Crater, completing a total of 72 flights by the end of its mission. The success of Ingenuity resulted in various research efforts to further explore Mars via vertical flight, including two optimized Ingenuity-sized helicopters proposed to retrieve samples for the 2028 Mars Sample Return mission. To aid in the design process for the two proposed Sample Retrieval Helicopters, both heritage and optimized, increased diameter rotors were tested at the NASA Jet Propulsion Laboratory in the 25-ft Space Simulator. Three test campaigns were performed using the Ingenuity rotors and optimized Sample Retrieval Helicopter (SRH) rotors for several rotor speeds, densities, configurations, and collectives to identify performance limitations. These three test campaigns included the Ingenuity Engineering Design Model 1 (EDM-1) with and without a cruciform box, Transonic Rotor Test (TRT) rig, and SRH Dual Rotor Test (DRT). Experimental setup, test matrix, data processing, data quality, and performance results for EDM-1, TRT, and DRT campaigns are presented and discussed. Experimental results from the test campaigns will aid in future experimental methods and validation efforts for planetary rotorcraft exploration.

Data Processing↗