NASA SBIR 02-1 Solicitation


PROPOSAL NUMBER:02- A7.03-9648 (For NASA Use Only - Chron: 022351 )
SUBTOPIC TITLE: Flight Sensors, Sensor Arrays and Airborne Instruments for Flight Research
PROPOSAL TITLE: Real-time Aeroelastic Measurement System (RAMS) for in-Flight Flutter Testing

SMALL BUSINESS CONCERN (Firm Name, Mail Address, City/State/Zip, Phone)
Tao of Systems Integration Inc.
471 McLaws Circle, Suite 1
Williamsburg , VA   23185 - 5525
(757 ) 220 - 5040

PRINCIPAL INVESTIGATOR/PROJECT MANAGER (Name, E-mail, Mail Address, City/State/Zip, Phone)
Siva Mangalam
471 McLaws Circle, Suite 1
Williamsburg , VA   23185 - 5525
(757 ) 220 - 5040

A high dynamic response, Real-time Aeroelastic Measurement System (RAMS) using microns-thin hybrid sensor arrays will be developed to provide simultaneous unsteady normal-pressure and tangential shear-stress distributions on lifting surfaces undergoing bending and torsion during in-flight flutter testing. The surface signatures obtained with these sensors will be used to simultaneously obtain, in real-time, the spatial location and dynamic characteristics of unsteady flow phenomena such as boundary-layer transition, vortex flows, flow separation, and shock (flow oscillations) and boundary oscillations (flutter). Surface signatures will provide accurate information on the amplitude and frequency of the aerodynamic forcing functions, as well as the time lag between unsteady aerodynamic phenomena and the structural response of the test article. RAMS will provide flight-test researchers with an effective tool to obtain time-accurate unsteady coupling physics of the aerostructural system by sensing surface signatures coordinated with pressure, strains, and accelerations. With the proposed measurements there will be an entire force-response description of the aerostructural dynamics. RAMS will result in a comprehensive measurement technology that can be used for routine flutter flight-testing, CFD validation, development of new and advanced design tools, development of active aeroelastic wing (AAW), and the development of flutter warning and active control systems.

RAMS will be of value to ground / flight-testing and health monitoring of fixed-wing and rotary-wing aircraft, turbo-machinery, propellers, unmanned vehicles, missiles, and space vehicles. Advanced aerospace vehicles tend to be slim and elastic, resulting in severe aeroservoelastic problems at high speeds, which require attention in both design and routine performance for safety and ride quality. All vibrating structures subjected to unsteady aerodynamic or hydrodynamic forces and moments are prone to aeroelastic and flutter problems, which could lead to catastrophic results unless properly taken care of. RAMS will be of value to the design and testing of sails of sailboats, high-rise buildings, chimneys of power and cooling towers of plants, masts of ships, and other structures subjected to vibrations in the presence of fluid flow.

RAMS has significant potential applications for the aerospace industry. Flutter is one of the chief limiting factors in the design of more efficient and more maneuverable high-speed aerospace vehicles. The proposed innovation will significantly contribute to the important recent initiative taken by NASA DFRC to develop Active Aeroelastic Wing (AAW). Aerodynamic nonlinear effects could be severe in the high transonic Mach numbers due to, for example, changes in the flow separation and shock wave patterns with amplitude of oscillation. Nonlinear effects are likely to become more important in the future as aircraft fly faster, are more flexible, and use complex control systems. The benefits of successfully addressing the flutter problem will lead to a larger safe-flight envelope and payload for aerospace vehicles, which can be translated to economic value, while simultaneously possessing superior maneuver performance.

Form Printed on 09-05-02 10:10