NASA STTR 2019-II Solicitation

Proposal Summary

Proposal Information

Proposal Number:
19-2- T15.01-2965
Phase 1 Contract #:
Subtopic Title:
Distributed Electric Propulsion (DEP) Vehicles toward Urban Air Mobility (UAM) and Regional Airliners
Proposal Title:
Air Vehicle Gust Response Analysis for Conceptual Design
Research in Flight
1919 North Ashe Court
Auburn AL  36830 - 0000
Phone: (334) 444-8523
Auburn University
141 Engineering Drive
AL  36849 - 5338
Phone: (404) 395-1694

Principal Investigator (Name, E-mail, Mail Address, City/State/Zip, Phone)

Dr. Imon Chakraborty
141 Engineering Drive Auburn, AL 36849 - 5338
(404) 395-1694

Business Official (Name, E-mail, Mail Address, City/State/Zip, Phone)

Dr. Roy Hartfield
1919 North Ashe Court Auburn, AL 36830 - 0000
(334) 444-8523
Estimated Technology Readiness Level (TRL) :
Begin: 3
End: 5
Technical Abstract (Limit 2000 characters, approximately 200 words)

The Controls and Load Alleviation Simulation Platform (CLASP) framework was developed in the NASA STTR Phase I activity preceding this Phase II proposal. CLASP has been created to perform time-domain simulations of gust and turbulence encounters with a focus on UAM and VTOL aircraft concepts. The centerpiece of CLASP is a Simulink flight simulation model that has been developed with significant modularity and modeling flexibility with regard to aircraft aero-propulsive, control system, and structural dynamics models as well as the definition of gust and turbulence characteristics. The NASA LA-8 configuration was used to demonstrate the developed capabilities of the CLASP framework. Phase I simulations were limited to considering the configuration’s forward flight mode, while Phase II will extend the framework capabilities to vertical flight mode as well.

The CLASP framework utilizes a hybrid aero-propulsive modeling approach in which strip theory is used to develop the loads on the fore and aft wings while lookup tables are used to represent the aerodynamic loads on the rest of the airframe. FlightStream® is used extensively for the aero-propulsive analysis within CLASP. A prototype semi-automated FlightStream® Reduced Order Model (ROM) was developed in Phase I and will be automated in this Phase II activity. This feature enables the data reduction necessary to integrate the flow solver into the CLASP framework with very high computational efficiency.

The modal approximation method is used to model the structural dynamics of the flexible fore and aft wings. Control system modeling in CLASP includes inner loop controllers for pitch-hold, bank-hold, and yaw damping; an altitude-hold autopilot function, and a proportional-derivative Gust Load Alleviation (GLA) control law operating on estimated gust-induced angle of attack

Potential NASA Applications (Limit 1500 characters, approximately 150 words)
  • The developed framework closely aligns with and supports two ARMD strategic thrusts: (i) Strategic Thrust 3: Ultra-efficient Subsonic Transports and (ii) Strategic Thrust 4: Safe, Quiet, and Affordable Vertical Lift Air Vehicles.
  • Enable multidisciplinary optimization workflows involving flight control system parameters and vehicle response to gust and turbulence.
  • Enable development of autonomous flight systems in dense urban environments with physics-based aero-propulsive and flight-control modeling in real-time.
Potential Non-NASA Applications (Limit 1500 characters, approximately 150 words)
  • Commercial: Commercialize the CLASP framework in FlightStream® for the UAM industry and NASA partner organizations.
  • Research: Generate a Modeling & Simulation (M&S) workbench to test upcoming gust alleviation and ride quality technologies.
  • Commercial: The CLASP framework provides effective support for structural modification, related certification processes and flight testing.
Duration: 24

Form Generated on 06/27/2021 15:51:46