NASA SBIR 2008 Solicitation


PROPOSAL NUMBER: 08-1 A2.04-9493
SUBTOPIC TITLE: Aeroelasticity
PROPOSAL TITLE: Novel Tools and Test Techniques for the Evaluation of Aeroservoelastic Free-play

SMALL BUSINESS CONCERN (Firm Name, Mail Address, City/State/Zip, Phone)
Systems Technology, Inc.
13766 South Hawthorne Blvd.
Hawthorne, CA 90250 - 7083
(310) 679-2281

PRINCIPAL INVESTIGATOR/PROJECT MANAGER (Name, E-mail, Mail Address, City/State/Zip, Phone)
Brian P Danowsky
13766 S. Hawthorne Blvd.
Hawthorne, CA 90250 - 7083
(310) 679-2281

Expected Technology Readiness Level (TRL) upon completion of contract: 3

TECHNICAL ABSTRACT (Limit 2000 characters, approximately 200 words)
Control surface free-play is important throughout the lifetime of a flight vehicle. Free-play can result in aeroservoelastic limit cycle oscillations (LCO) with significant amplitude causing degraded mission effectiveness, possibly leading to structural failure. Specifications for allowable free-play size can be overly conservative. Analytical tools are proposed for establishing free-play limits on aeroservoelastic aircraft systems without adverse consequences, justifying relief, which may otherwise be cost prohibitive or impossible to satisfy. The proposed tools include finite element modeling, model order reduction, nonlinear simulation, describing functions, and wavelet transforms. These tools will be integrated into the MatlabTM/SimulinkTM platform. A trade study is proposed that compares different free-play modeling techniques. Novel techniques will be used to determine the airspeed range over which limit cycles can occur, including the frequency and amplitude of the limit cycles. Novel techniques for the inverse problem are also proposed, whereby the free-play size is estimated based on diagnostic measurements. A general stabilator model will be used in Phase I to develop the analysis techniques and show feasibility. Wind tunnel test verification of the free-play analysis and estimation techniques will be conducted in Phase II using existing wind tunnel models and facilities at an industrial location.

POTENTIAL NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
NASA is a research leader in aeroservoelasticity. Recent advances include innovative experimental excitation mechanisms for more accurate vibration data, wavelet analysis for signal processing, stability estimation and nonlinear identification, and robust flutter boundary prediction. The proposed work naturally follows from and compliments these topic areas. This program will lead to a validated software tool for control surface free-play analysis and identification. This will be a valuable asset for the many NASA programs that involve the design, analysis, and test of air vehicles. Free-play is an area of concern for both transports and high performance aircraft including those routinely used at NASA DFRC. These aircraft will normally go through analysis, ground loads testing, and aeroservoelastic testing to ensure safe operations for the given research mission. The tools developed for this program will provide a means to accurately analyze, predict and identify the effect of aeroservoelastic free-play for many NASA programs

POTENTIAL NON-NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
STI also has long standing relationships with numerous manufacturers of both commercial and military aircraft. This places STI in a unique position to demonstrate this product directly to likely potential industry users. This program will lead to a validated software tool for control surface free-play analysis and identification. The software can be used for aircraft design, flight test operations, post-flight test analysis and actuator maintenance testing. On-line identification of free-play is also a potential application. Target markets are military and commercial aircraft manufacturers. Other markets include industrial machinery and structural analysis.

NASA's technology taxonomy has been developed by the SBIR-STTR program to disseminate awareness of proposed and awarded R/R&D in the agency. It is a listing of over 100 technologies, sorted into broad categories, of interest to NASA.

Controls-Structures Interaction (CSI)
Simulation Modeling Environment
Software Tools for Distributed Analysis and Simulation
Structural Modeling and Tools

Form Generated on 11-24-08 11:56