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Chris Miller

Publications and source records attributed to Chris Miller.

7 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2023

Flying Beyond Flutter with the X-56A Aircraft

The National Aeronautics and Space Administration X-56A Multi-Utility Technology Testbed was successfully flown beyond flutter using active feedback control methods. This report discusses the flight-test methods used during envelope expansion and presents the data collected. The frequency and damping of rigid-body flight dynamic modes and the first two structural modes were estimated from the flight data. The flutter mechanism (body freedom flutter) was found to match predictions with coupling occurring between the short period and the first symmetric wing bending mode. Flights up to the instability threshold and beyond were conducted using active feedback control. Several tests were conducted in flight where the control system was disabled momentarily to observe the unstable flutter mode and then reengaged; thus, demonstrating active suppression.

Jacob Schaefer↗
NASA NTRS2023

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↗
NASA NTRSDate not supplied

Moog SureFly® Hover Test Update

An update on the Moog SureFly vehicle acoustic hover test is presented. The intent of the effort was to acquire data that will be used to identify the acoustic far-field for the vehicle and the importance of electric motor noise relative to other sound sources for hover. The data will also be available to assess sound levels for future vertiports. The flights were completed in June 2022 at the Cincinnati Municipal Airport – Lunken Field.

jet noise↗
NASA NTRSDate not supplied

NASA Armstrong Flight Research Center Dynamics and Controls (530)

AFRC Controls and Dynamics Branch - Research Areas: - Traditional GN&C - Classical and advanced control algorithms - Risk based approaches for safety critical applications - Integration of novel sensors and sensor fusion (FOSS, LIDAR, etc.) - Trajectory optimization and control - Flight/System Dynamics - Equations of Motion and integrated modeling of vehicles and vehicle systems - Unique and novel vehicle dynamics - Methods for extracting relevant vehicle dynamic information from flight data - Human and vehicle interfaces and interactions - Handling Qualities and Pilot-in-the-loop oscillations (PIO) predictions and design metrics - Ride quality research - Autonomy - Novel algorithms, sensors, and sensor fusion - Bounding risk for testing automated systems - Pilot/Operator interactions - Engineering Support and Airworthiness Assessments - Aircraft modifications and experimental configurations

Chris Miller↗