A Datum-Based model for Practicing Geometric Dimensioning and Tolerancing

摘要

Geometric dimensioning and tolerancing (GD&T) is an important step in product design. It has a significant impact on product manufacturing, quality, and functionality. As a specific program criterion of ETAC (Engineering Technology Accreditation Commission) of ABET, all Mechanical Engineering Technology programs are required to teach GD&T At our university, GD&T is a core course for Mechanical Engineering Technology, Manufacturing Engineering Technology and Mechanical Engineering majors. Houvvem; GD&T is a tedious and challenging process. There has been no integrative or systematic rule to follow when practicing GD&T. Incorrect GD&T call-outs are common in engineering drawings. In this paper, the authors introduce a layered model by which the GD&T practice can become standardized, more accurate, and less complicated. The authors have implemented this model in teaching GD&T, and the assessment result of student learning is promising. The model provides an effective tool for teaching, learning and practicing GD&T It highlights an important and timely contribution to the development of the mechanical and manufacturing engineering technology curricula.