SARISTU - Smart Intelligent Aircraft Structures

The concept of Smart Intelligent Aircraft Structures offers significant improvements in aircraft total weight, manufacturing cost and, above all, operational cost by an integration of system tasks into the load carrying structure. The project focuses on integration activities in the three distinct technological areas airfoil morphing, self-sensing and multifunctional structures through self-healing and the use of nanoreinforced resins.

Short Description

Motivation

For the first time ever in smart material concepts, SARISTU thereby offers the opportunity to physically assess the combinations of different technological solutions and their combined effect at full aircraft level. Morphing technologies, which already have significant capabilities on their own as described below, may only be implemented in production aircraft if combined with further functionalities such as de-icing, independent shape assessment and, if used for active aeroelastic tailoring, wingbox strain assessment as offered by Structural Health Monitoring (SHM) techniques. Nanoreinforced resins used for damage tolerance improvements on the other hand, may be combined with damage detecting capabilities affecting design allowable to further increase potential weight savings.

Objectives

Morphing technology integration on a typical outboard wing is expected to achieve a total fuel consumption reduction of 3% and reduce the impact of air traffic noise by 6 dB(A)
The feasibility of combining Structural Health Monitoring (SHM) with nanoreinforced resins for Damage Tolerance improvement for weight savings exceeding 3%
Highly loaded areas such as the wing and rear fuselage structures to provide information on the local loading and health for reduced structure related operational cost (up to 1%)

Content

The term Morphing typically refers to shape changing structures. Although this concept is well established in the aircraft industry through the implementation of high lift devices, it is not a structure inherent ability. Dedicated systems are required to deploy structural sections which in themselves do not change their shape.
The technological advances integrated within SARISTU each have the capability to provide individual step changes in aircraft design, manufacturing and operations on their own. Integrated jointly and during the earliest feasible manufacturing steps, their combined improvements are multiplied. Winglet trailing edge morphing for example, is capable of optimizing drag during the landing and take-off phases. If coupled to an integrated strain monitoring system in the main wing box however, its capabilities may be used for active aeroelastic tailoring as well. On the fuselage structure, a combination of strain sensing and acoustic damage sizing or a combination of damage indicating surfaces and acoustic damage detection results in a drastic NDT time reduction for manufacturing, assembly and aircraft operations. Prior to an overview of the state-of-the-art and targeted innovation.

Methodology

Focusing on the implementation of leading and trailing edge as well as winglet trailing edge conformal morphing in three distinctly separate application scenarios, they shall be validated jointly in a series of major tests and one numerical exercise:

To validate the fuel consumption reductions achievable by Leading edge morphing, trailing edge morphing, winglet trailing edge morphing and the combination thereof, a wind tunnel test at full scale is needed. This is due to the need to obtain representative aerodynamic loads on the structure under verification. To limit the scope of this work, an outer wing section shall be used. Due to wind tunnel constraints, this verification is limited to low velocities.
Following wind tunnel performance verification, structural testing needs to be undertaken to validate the structural performance in particular of the leading and trailing edge surfaces under extreme loading conditions. Furthermore, the performance of low-cost Structure Health Monitoring integration in particular on the lower wing panel shall be verified.

SARISTU Presentation

Morphing Wing

Funding program: FP7