Overview
The proposal approached innovative solutions for the design and manufacturing of the test rig and the definition of the method and performance for the structural testing of two different kinds of configuration for the outer wings within a Smart Fixed Wing Aircraft.
The WISDOM proposal understood that the test philosophy is to demonstrate that major components tests can be performed on flight test aircraft. The main requirement for this wing structural part was based on their high dimensional stability and tight geometrical tolerances to compliance with surface quality for a natural laminar flow condition, and therefore stability control and manufacturing precision over the test bench tools to be designed and manufactured shall consider this, avoiding as much as possible interfaces with the specimen surfaces. The test procedure was based on a Self-supporting test rig with flexible and adaptative plug and play loads introduction method with minimum specimen interface needs and wireless connection for data recording.
Funding
Results
Project Context and Objectives:
This proposal main objective was to approach an innovative and reliable solution for the design, manufacturing, set up and commissioning and performance & analysis of the structural test of the port and starboard outer wing sections needed for flight tests of natural laminar flow on the SFWA flight test demonstrator under Clean Sky Program.
The challenge of this proposal was to define the test method necessary to demonstrate that major components tests can be performed on flight test aircraft.
Currently wing bend test methods are destructive, incurring in high cost. The main goal of this proposal was to develop a NON-DESTRUCTIVE method for wing bend tests, innovating in minimum test bench-wing interfaces, Non-destructive inspection methods (infrared thermography) and wireless data recording.
The main goal was to prove that some of the technical solution applied to perform this test are reliable enough to be applied from now on for future aircraft test full scale and fatigue parts test. The main improvements are:
- Use of High Precision Servo-controlled Winches (HPSW) instead hydraulics jacks to perform bending up test. These elements will avoid hydraulics means to perform tests and use of electrical devices, making it cleaner and safety than nowadays.
- Use of IR technics: Infrared Thermography (IRT) as a Non Destructive Test tool is a fast system of inspection which can complement the conventional methods of NDT (ultrasounds, radiography, eddy-current, magnetic particles, tap-coin) where these ones have difficulties or are simply unsuitable, as sometimes it happens in the aeronautics industry. As NDT technique, IRT is theoretically suitable for every type of materials. It can be applied to inspect compound materials as well as metallic materials, what makes this technique be more versatile than many other conventional methods (in addition to its manageability and applicability in production and maintenance labours).
Wireless data acquisition system: For this kind of test it will be investigated and implemented a contactless system for deflection measurement.
The system was based on local GPS system but not only. The main idea was to provide a 3D map of the deflecting surface in order to be easily compared with FEM models.
The aim was to implement contactless measuring systems, besides the main idea to install the local GPS system other measuring techniques can be used.
A second objective of this work package could be the utilisation of a distributed and wireless acquisition system. Traditionally the use of wireless data acquisition systems had been avoided mainly due to limitations into the transmissions rates due to the inherent bandwidth limitation associated with the standards used in the past. However, the last advances in the wireless protocols and the new industry standards could lead to new opportunities in this field.
Vision systems: The use of a group of high-resolution cameras placed on the test tool structure will be used to measure the deformation deltas of the wing structure. This device will be complemented by the use of light projection to be able to analyse the contrast shadows in the surface of the element that will give information of the deformation cycles.
This works also required a pre acquired data of witness deformations to be able to recognise those patrons in the real structure.