Abstract:With the goal of establishing a locating layout with the minimum number of workpiece locating points to meet the process requirements,the geometric theorem of workpiece positioning based on the location normal as the medium,the relationship between the workpiece degrees of freedom and the location normal was inferred,and the location normal information of the degree of freedom constraint model was obtained; the mathematical model of the workpiece degrees of freedom was established,the logical subtraction algorithm was used to establish the relationship between each type of workpiece degrees of freedom,and the planning schemes of the degree of freedom model was obtained.The initial layout of positioning points was derived from the location normal information in the planning scheme.The application process of workpiece locating point layout planning based on location normals was introduced in detail using a typical example.The method requires only the degree of freedom information,and the planning process is simple,which is suitable for the initial locating scheme design of various types of workpieces,especially complex workpieces.