Research On In-machine Measurement And CAD Model Reconstruction For Wide-chord Fan Blade Contour

Wide-chord fan blade is widely used in aero engine and its manufacturing process is one of the main factors affecting the development of the aviation engines. Blade blanks using superplastic forming and diffusion bonding manufacturing technology, which results in the size deviation phenomenon. all kinds of blades are manufactured using five axis NC machining technology based on profile model In addition, blade measurement data is huge. digital analog reconstruction directly means a large amount of calculation and low efficiency which needs to preprocess the data. The main content is just as follows:(1) Wide-chord fan blade measurement technology is studied. The normal methods contain binocular vision method, three coordinate measurement method and laser method. They are evaluated by the efficiency and the match precision of measurement results. After that, the better measuring method is suggested.(2) The measurement method of wide-chord fan blade is studied. The acquisition of the measurement surface, the distribution of the measuring points and the planning of the measuring path are researched. The five axis simulation is done and the measurement process is verified in Ultrasonic 20 linear.(3) The surface reconstruction technique of the blade is studied. The data reduction is based on the distance, the number and the curvature and the reconstruction use NURBS method. The registration of the blade coordinate system and rough CAD model coordinates are accomplished with the help of ICP method. Finally, the measuring-online model and reconstruction model Interface are designed.