American Society for Engineering Education
2014 ASEE Annual Conference & Exposition
Machine Design Experiments Using Mechanical Springs to Foster Discover Learning For the typical undergraduate engineering student the topic of mechanical springs is introduced and discussed in several courses. A first exposure may be in a physics course, where springs are presented as idealized mechanical energy storage components. Springs store potential energy,complementing masses that store kinetic energy and dampers that are resistive and offer no energy storage capability. In an electrical circuit course, springs are often presented as the analog of either capacitors or inductors, depending on which analogy is used. For mechanical engineering students, springs are a core component studied in machine design courses, where the nomenclature and design equations are developed for various types of springs. There may be a rudimentary exposure to real springs in a mechanical engineering laboratory; more often,students may see real springs passed around in class and as part of demonstrations.In this paper we describe new experiments that were designed to provide mechanical engineering students with discovery learning experiences with springs. The suite of practical experiments presents students with a range of challenges that require them to analyze, measure, design, and fabricate springs. Activities in the experiments include: (1) Identifying spring types (tension, compression, torsion) and appropriate applications (automotive door latches, bicycle suspensions, pens). (2) Disassembling and re-assembling a padlock (with design and manufacturing questions related to its springs, and measurement of the stiffness of the shackle compression spring). (3) Creating linear and nonlinear stiffnesses from series and parallel combinations of a set of springs (requiring stiffness measurements of the given springs and determining desired stiffnesses to achieve target natural frequencies). (4) Designing linear, hardening, and/or softening springs for different applications, fabricating the springs via rapid prototyping (3D printing), and testing their suitability.In addition to reporting the details of the experiments, we share experiences of students and teaching assistants in their use and effectiveness. We provide insights into how well students became familiar with types and nomenclature of springs and understood the applicability of different springs to actual real-world problems. The intent of the experiments is to effectively enhance mechanical engineering students' awareness of springs and expand their knowledge and confidence in spring design.
Malak, Peter William and Nagurka, Mark L., "Machine Design Experiments Using Mechanical Springs to Foster Discovery Learning" (2014). Mechanical Engineering Faculty Research and Publications. 215.
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