基于投影条纹级次识别的发动机叶片三维测量方法

Three-Dimensional Measurement Method of Aero-Engine Blades Based on Projected Fringe Order Identification

针对民航发动机叶片面型的精密检测问题,提出了一种基于条纹级次识别的民航发动机叶片测量方法。首先设计了组合结构光三维测量系统,并采用圆心拟合的方法对系统的旋转轴进行了标定,接下来采用数字条纹投影法对航空发动机叶片进行了测量。在相位解包裹过程中,采用投射二维码图样结合双目视觉的方式,实现了对投影条纹级次的识别,并且对叶片的前后表面分别进行了重建。在叶片点云拼接过程中,提出了旋转轴与迭代最近点算法相结合的三维拼接方法。实验结果表明,该方法不依赖于特征提取,有效解决了叶片表面特征不足的问题,能够实现叶片结构快速准确的三维重建。

Aiming at the precision measurement problem of the profile of aero-engine blades, a measurement method based on projected fringe order identification is presented. Firstly, a three-dimensional measurement system with composite structured light is designed and the rotation axis of the system is calibrated by the method of center circle fitting. Then, the aero-engine blades are measured by the digital fringe projection method. In the process of phase unwrapping, the projected fringe order is recognized by projecting two-dimensional code pattern combined with binocular vision, and the front and back surfaces of the blade are reconstructed respectively. In the process of point cloud data stitching, a three-dimensional stitching method combining rotating axis with iterative closest point algorithm is proposed. The experimental results show that the method does not rely on feature extraction and effectively solves the problem of insufficient surface features on aero-engine blades. Which can realize fast and accurate three-dimensional reconstruction of aero-engine blades.