Using 3D Printing and Physical Testing to Make Finite-Element Analyis More Real in a Computer-Aided Simulation and Design Course

The mechanical engineering curriculum at Loyola University Maryland includes a junior-level course in computer-aided simulation and design (EG426). In this course, students use SolidWorks ® to create computer models of three-dimensional parts and assemblies and learn how to generate engineering-quality design drawings. The class also covers the use of finiteelement analysis (FEA) to evaluate stresses and deflections of parts under load. Ultimately, the course culminates in a professional project where each student designs a mechanical part to meet a set of specific performance requirements, utilizing a design process that includes the iterative application of FEA. The course is generally very popular with students and alumni who comment favorably on its practicality and applicability in industry. Unfortunately, until recently, the Engineering Department’s manufacturing equipment made it impractical to have the students actually fabricate their designs. In the spring of 2013, a Stratasys Objet Model 30 3D printer was purchased to expand our rapid prototyping capabilities. This technology was a natural fit for incorporation into EG426, and changes were subsequently made to do so. Instead of being a purely digital and paper exercise, the students were asked to fabricate their final designs using the 3D printer and to subject their parts to physical testing to verify that certain performance requirements had been met. This also allowed them to compare the deflection predictions (made using FEA) with the actual deflections under load. The overall goal of these changes was for the students to come to a clearer understanding of how the successful and informed execution of FEA in the design process could positively affect the ultimate performance of their designs. The effectiveness of this active, project-based learning approach was assessed through instructor evaluation of student performance, student questionnaires, and solicitation of oral comments. Written student evaluations of the experience indicated that the students (1) enjoyed actually seeing their products come to life, and (2) developed a better understanding of how FEA could be used to guide and enhance their designs. Suggestions for improving the incorporation of 3D printing in the course, based on both student comments and instructor reflections, are discussed.