“…The contents of CAT relate to the aspects of tolerance specification and standardization, product design, manufacture, inspection and measurement of tolerance, product life cycle management, and functional tolerancing. 13 It is a very important problem for CAT to express tolerance semantic information that can be read and understood automatically by computer through tolerance model and to exchange information between different heterogeneous CAx (CAD, CAE, CAM, etc.). 14 Tolerance models such as tolerance maps (T-Maps)model, 15,16 small displacement torsor (SDT) model, 17,18 Jacobian-Torsor model, 19 offsetting model, 20,21 kinematic model, 22,23 degree of freedom (DOF) model, 24,25 vector equation model, 26,27 belong to the interpretation model, and the computer cannot read and understand their meaning directly.…”