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Abstract Learning by doing has proven to have numerous advantages over traditionally taught courses in which the instructor teaches the topic while students remain passive learners with little engagement. Although laboratories give hands-on opportunities for undergraduate mechanical engineering students, they have to wait for a semester for the lab course for instance the prerequisite of the vibrations and control laboratory is the mechanical vibrations course. Since the nature of the dynamics branch consisted of dynamics, vibrations, and control theory courses are highly mathematical, students struggle comprehending the introduced topic and relate the theory to its real-world application area. Furthermore, it’s almost impossible for an instructor to bring the existing educational laboratory equipment to the class since they are bulky and heavy. The advents in manufacturing technology such as additive manufacturing bring us more opportunities to build complex systems new materials. This study presents the design, development, and implementation of low-cost, 3D printed vibratory mechanisms to be utilized in mechanical vibrations, control theory courses along with their associated laboratories. A pendulum, cantilever beam integrated with springs, and a rectilinear system consisted of two sliding carts, translational springs, and a scotch yoke mechanism are designed. The main parts of the mechanisms are 3D printed using polylactic acid (PLA), polyethylene terephthalate glycol (PETG), and thermoplastic polyurethane (TPU).
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Designing and 3D Printing Lab Equipment for Mechanical Vibrations Course and Laboratory: Work in Progress
Abstract Undergraduate mechanical engineering students struggle in comprehending the fundamentals presented in an introductory level mechanical vibrations course which eventually affects their performance in the posterior courses such as control theory. One salient factor to this is missing the visualization of the concept with hands-on learning since the vibrations and control laboratory course is offered in the following semester. This study presents the design, development of three portable and 3D-printed compliant vibratory mechanisms actuated by a linear motor and their implementation in vibrations course and vibrations and control laboratory. The proposed setups consist of flexible and compliant springs, sliders, and base support. Mechanisms are utilized to demonstrate free and forced vibrations, resonation, and design of a passive isolator. In addition to the 3D-printed, portable lab equipment, we created the Matlab Simscape GUI program of each setup so instructors can demonstrate the fundamentals in the classroom, assign homework, project, in-class activity or design laboratory.
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- Award ID(s):
- 2002350
- PAR ID:
- 10334758
- Date Published:
- Journal Name:
- ASME 2021 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference
- Volume:
- V004T04A012
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1115/DETC2021-71427
