Achieving tight tolerances on wing waviness and roughness during production is a seemingly simple and low-technology route. In reality, measuring large areas during manufacture and assembly with high lateral and depth resolution is no easy task, and no system capable of doing so currently exists. The EU-funded WIMO (Outer wing metrology) project provided an in-line quality control solution by combining different measurement systems into a single unit. Development requires not only the instrumentation for measurement, but also innovative strategies for analysing the huge amount of data. Project partners developed an integrated metrology system ahead of the measurement campaigns. It is custom-built for the specific requirements of wing metrology. They carried out extensive test measurements and created an automated calibration procedure to transform the measured data into a global coordinate system. In addition, a tool was implemented that enables on-site measurements performed by manufacturing personnel with the assistance of experts via remote control. The WIMO team defined requirements for the overall measurements and developed procedures for data evaluation. It then focused on the performance of the measurement campaigns up to the final wing assembly phase. Researchers successfully demonstrated the metrology system and its performance, and a stereo camera system for metrology. The nominal field of view makes it suited for measurements on inter-rib spaces, nose and the upper cover of wings with high accuracy. The system can be adjusted to any desired orientation, and its position can be registered with laser tracker assistance. As a result, it is possible to locate unconnected surface segments correctly in 3D space, thus eliminating the need for large overlaps between surface sub-areas. WIMO delivered a groundbreaking integrated metrology system to ensure wing surface quality during production of the new NLF wing. The resulting smooth laminar flow during flight will significantly reduce fuel consumption and associated emissions for greener air transport.
Wing surfaces, natural laminar flow, WIMO, outer wing metrology