Corresponding point matching method for workpiece entity and workpiece three-dimensional CAD model

The invention provides a corresponding point matching method for a workpiece entity and a workpiece three-dimensional CAD model. According to the invention, workpiece photo contours in all views are calculated; spatial coordinate points are obtained by adopting a three-dimensional expansion mode; an extreme point of each coordinate is taken as a key point; extreme points on all coordinate axes arealso selected from the three-dimensional CAD model; included angles between every two key points in the three-dimensional CAD model of the workpiece are calculated by utilizing a cosine law as structured basis, key points on a workpiece object are subjected to the same processing; the set is traversed to obtain a matching mode with a minimum error between the two sets, thereby calculating a conversion matrix of the two sets, multiplying the three-dimensional CAD model points by the conversion matrix to obtain key point coordinates in a real object, and realizing visual matching of the mappingrelationship between the