Dynamic Modeling With Constraint Based Cad In Introductory Engineering Graphics

This presentation is part of an ongoing research project by the authors looking at how constraint-based 3D modeling can be used as a vehicle for rethinking instructional approaches to engineering design graphics. A particular goal is moving from a mode of instruction based on the crafting by students and assessment by instructors of static 2D drawings and 3D models. Instead, an approach based on dynamic modeling is proposed. This approach provides the opportunities for students to learn about geometry through the embedding of geometric behaviors into models and then testing these behaviors via dynamic change of the model. An advantage to dynamic modeling is the ability to provide visual embodiment to the underlying logic of the constraint strategy, providing direct feedback to the student and a straightforward mechanism for assessment by the instructor. Also, this approach mimics the real-world activities of engineers and designers executing 'change orders' on their virtual product models. As such, this approach is better aligned with larger goals of better problemsolving abilities in the technology and engineering workforce. A previously developed taxonomy of geometric behaviors is used to guide the development of activities that provide an appropriate range of activities for the students. Example instructional activities will be presented..