Inverse Finite Element Method (iFEM) Investigation for Adaptive Structures

Inverse Finite Element Method (iFEM) Investigation for Adaptive Structures

This research project is evaluating an innovative technique that uses fiber optic strain sensors to measure structural deformations and full-field strains. An iFEM analysis reconstructs a deformed structural shape based on the strain measurement data simulated by FEM analysis to represent the in situ strain measurements. Mapping the iFEM displacement solution onto a full FEM model without the applied loading allows the complete fields of displacement, strain, and stress to be reconstructed to a high degree of accuracy. The innovation improves safety by enabling more efficient health monitoring of control surfaces and flexible structures. This project supports work on multiple flight research projects at Armstrong.

Work to date: The team has completed and validated a one-dimensional beam element test using a compliant slider mechanism.

Looking ahead: Future plans involve developing and validating the algorithm on a full-size flight test article.

NASA Partner: Langley Research Center

Benefits

 Accurate: Enables accurate full-field structural shape and strain measurement

 Economical: Uses a minimal number of sensors to recreate the full-field structural deformations and strains

Applications

 Aircraft wing flaps   Motor vehicles

 Helicopter blades    Trains

 Wind turbines   Ships and submersibles

Hyperelastic Research/Lightweight Flexible Aircraft

Armstrong engineers are pioneering new research in aircraft design and modeling. Researchers are experimenting with revolutionary hyperelastic wing control technologies that can reduce weight, improve aircraft aerodynamic efficiency, and suppress flutter. Other cutting-edge research involves techniques, models, and analysis tools for flutter suppression and gust-load allevia-tion.Flight projects at Armstrong rely on high-performance aircraft that can support research on lightweight structures and advance control technologies for future efficient, environmentally friendly transport aircraft. This work has applicability beyond flight safety and design optimization.Armstrong's R&D capabilities in this area also can be applied to other vehicles, such as supersonic transports, large space structures, and hypersonic vehicles.