Cooperative machining method for large sandwich component

The invention discloses a cooperative machining method for a large sandwich component. The method comprises the following steps of: performing scanning measurement on an actual cooperative curved surface of a face plate skin by utilizing a handheld self-positioning three-dimensional laser scanner to obtain data point clouds of the actual cooperative curved surface of the face plate skin; removing impurity points and noise points from the point clouds, optimizing point cloud number, and performing wrapping operation on the data point clouds to generate a polygonal curved surface; performing operation such as repairing, correcting and the like on the polygonal curved surface, and establishing a grid and a curved surface by detecting curvature and an outline so as to obtain an actual cooperative curved surface computer aided design (CAD) model of the face plate skin; performing numerical control programming on the actual cooperative curved surface CAD model by utilizing CAD/computer aided manufacturing (CAM) software to generate a numerical control machining program of the surface of a sandwich; respectively machining upper and lower surfaces of the sandwich at a numerical control machining center; and bonding and curing the machined sandwich and upper and lower face plate skins. The cooperative machining method realizes the scanning measurement, data processing and numerical control machining of the large sandwich component and has low investment cost, high machining precision and high universality.