Feature specifications are important composite parts in the new generation of geometrical product specifications and verification (GPS). According to the theories of specification model of shaft parts, this paper presents a method to generation of specification model of concentricity. Firstly, the mathematical model of concentricity is established in terms of nominal geometrical features of product for the parts the functional requirement are satisfied. Secondly, the simulation points of the model are generated by using the methods of axial stratification and circumferential multi-angles. The concentricity specification model could be generated after these operations of association and collection. Finally, an example is applied to illustrate the new method. The experiment results show the effectiveness of the proposed method.

In order to build the software evaluation and testing platform for surface topography measuring device and related enterprise, it is urgent to exploit the surface topography measurement and evaluation standard software application system. This paper proposes a novel method of surface topography design software base on exiting international standards. The method is introduced to obtain the reference line of surface profile. According to the reference line of surface roughness defined by the related standards, the functional evaluation parameters of surface characteristics were calculated. The procedure in designing the graphical user interface (GUI) is given based on the MATLAB software platform. This method realizes the software system that can evaluate the parameters of surface topography. The experimental analysis results show that the surface topography functional evaluation software using MATLAB has simple structure and reliable performance.