A method to generate AWJ cutting path for a large-size part without well-defined location characteristics

Abstract

Machining composite parts is a challenging manufacturing process. Many of these composite parts are not only with very large sizes but also lack of well-defined location characteristics. And usually, these composite parts are with burrs distributed on the periphery that require trimming. An industrial robot equipped with an abrasive water jet (AWJ) has been proved to be an effective method for trimming composite parts. This article proposed a method to solve the problem of trimming large-size composite parts without well-defined location characteristics with an AWJ robot. A standard block is bound on the end effector of the AWJ robot, as a locating reference. Then, by moving the AWJ robot so that this standard block is at the proximity of selected regions, the selected regions, along with this standard block, are scanned with a portable laser scanner. With the help of the standard block, a local coordinate system is established for the point cloud generated at each region. And further, the point clouds of these several regions are constructed into an integrated point cloud system through coordinate system transformation. Therefore, without using a large batch of magnetic stickers, a point cloud system of the large-size part is obtained. Finally, by matching the point cloud system with the 3D model of the expected final product, the 3D model of the expected final product is used to generate the tool cutting path with a special 3D CAM program. With this method, trimming large-size composite parts without well-defined location characteristics becomes realistic.