基于激光测量的航发叶片表面几何缺陷识别技术

Aimed at aero-engine blade repair detection, a method of blade surface defect identification based on the first-order cross-sectional guideline method is proposed. In this method, the cross-section data of the measurement point cloud is processed by the contour line method and the smooth curve is fitted by the B-spline interpolation function. The first-order derivative of each measuring point is obtained by the first-order derivative formula of the B-spline curve. If the curve is smooth, the slope of the measuring point on the curve changes between the slope values of the two endpoints, otherwise it indicates that there are defects in the curve. According to the nearest k-d tree point search algorithm, traversing the entire blade pot (blade back) can find the blade pot (blade back) on the defect area. By comparing with the three-coordinate measurement experiment, the technology can realize the defect identification with a 3 μm precision.