Spatial demonstration tools for teaching Geometric Dimensioning and Tolerancing (GD&T) To first-year undergraduate engineering students

Abstract

Geometric Dimensioning and Tolerancing (GD&T) is a design tool and symbolic language that allows design engineers to communicate design intent and requirements, with particular attention to function and relationship of the part features, to individuals who will manufacture the parts. GD&T can lower costs by reducing waste parts, and increasing uniformity, completeness and interchangeability of parts in manufacturing. GD&T is a topic that employers consistently request that undergraduate students know and understand, both at graduation and during undergraduate summer internships and coops, as early as the summer after their first year. GD&T can be a particularly tricky topic to teach due to its complexity, breadth of information, required spatial reasoning, and, commonly, lack of prior exposure to the topic. To assist students in developing spatial understanding, GD&T at a basic level has been developed for a first year undergraduate engineering CAD, sketching, and visualization course, including a set of hands-on demonstration tools and an interactive activity. This paper describes those tools and how to make your own set, along with some suggested activities to help students engage with and retain the concepts. The tools can be made with inexpensive materials, requiring only clear plastic sheets (PVC, acrylic, etc.), clear tape, permanent marker, and colored paper. These activities and materials have been used in a course with 9 sections of 50 students each, which indicates appropriateness and feasibility for classes of a similar scale.