Session: 10-05-01: Applied Mechanics, Dynamic Systems, Experimental and Computational Methods, Modeling and Virtual Simulations of Dynamic Structures, Advanced Materials and Testing

Paper Number: 166534

A Vital Case Study for a Model Based Definition (MBD) Course in Engineering Curriculum 

The manufacturing industry is evolving and has started using model-based definition (MBD). MBD is an approach to product development and design that emphasizes the use of 3D digital models as the commanding source of information for defining a product's characteristics, specifications, and requirements. The industry is using MBD as a way to transition away from using traditional paper-based drawings and documentation due to their immense drawbacks and limitations. MBD replaces or supplements these drawings with annotated 3D models that contain all the necessary information to define the product. MBD establishes a common information model that is populated with data that are common amongst different models in different stages of the product lifecycle becoming the source authority that drives all engineering activities, namely, from design inception, prototyping, manufacturing, inspection and quality control to complete product realization. This paper supports MBD as the necessary model across all industries and as such, its implementation in engineering curricula is vital. This will assure education, training and smooth transition of our future workforce to industry. Geometric Dimensioning and Tolerancing (GD&T) datum schema is a significant portion of the common information model of MBD. Although, GD&T has now been there for decades and strives to bring unique interpretation of the embedded design intent in the 3D CAD or the 2D drawing, the traditional paper-based 2D drawing print is still susceptible to misinterpretation. Even with proper documentation, misinterpretations can occur if not everyone involved in the design, manufacturing, and inspection process has a thorough understanding of GD&T principles. To some extent, GD&T is notorious for the challenges difficulties to learn and master it. A real-life detailed case study is presented on how a 2D engineering drawing print interpretation and seemingly unequivocal GD&T datum(s) reassignment by manufacturing lead to an engineering fiasco. Further, the case study also details how the implementation of MBD provides a fool-proof and fail-safe approach to the same design and wouldn’t allow any automatic modification to the product manufacturing information (PMI). As a result, the engineering fiasco mentioned earlier would be avoided come what may. This case study would usher the motivation for implementing MBD in engineering courses like, freshmen and sophomore engineering design, machine design, manufacturing processes, senior capstone design, etc. Further, the case study would also reinforce the understanding of the basic GD&T design principles for tolerance and datum assignments and its unambiguous interpretation across the board – Design, Manufacturing, Quality/Inspection.

 

Presenting Author: Chittaranjan Sahay University of Hartford

Presenting Author Biography: Dr. Sahay has been an active member of ASME and has been publishing in the areas of Design, Manufacturing and Metrology for the past 50 years.

Authors:

Chittaranjan Sahay University of Hartford
Geoff Foulds Origin International Inc.
Bob Stone Origin International Inc.
Suhash Ghosh Mechanical Engineering, University of Hartford
Claudio Campana University of Hartford