Abstract
Contemporary CAD systems support GD&T specifications simply as textual attributes which does not facilitate validation of dimensioning and tolerancing. The Y14.5 tolerance standard is quite complex and many engineers are not quite familiar with all this intricacies. A few expert systems have been developed for GD&T support but they typically focus on tolerance values and their cost consequences. This paper presents the design and implementation of an integrated system for specification and automatic validation of dimensioning and tolerancing schemes in conformance with Y14.5. The validation includes not only tolerance values but choice of datums and datum reference frames. Additionally, the GD&T specifications are checked against good practice rules. This paper also provides a compilation of such rules from a variety of sources.
