The paper presents a project-based course on Precision Engineering. During the course, the students have lectures and five labs in the beginning five weeks of the course, during which time they also choose a project from a set of proposals to illustrate the principles of precision engineering they are learning. Teams of 3-4 students are formed and preliminary design is carried out during this first half of the course. During the second half, they carry out the design to provide a working prototype and finally they give a final presentation. The collection of the proposals is performed with the support of internal (i.e. researchers) and external customers. The supporters are asked to suggest a high-compliance, high-sensitivity displacement gauge for measuring for example the deviation from straightness of a straight edge or deviations from roundness of a sphere or cylinder. The probe must have low force, sensitivity much smaller than typical 5flm of a Coordinate Measuring Machine, it must be compatible with commercial A/D converters and standard electronics, and it has to be realized by a combination of mechanical amplifica- tion and using technology that lends itself to trouble-shooting by technical assistants of a variety of backgrounds. The paper illustrates the design and the development of one of the proposed projects, by discussing the design issues, the prototype manufacturing, and the testing phase. The paper then discusses how the project-based approach can strengthen and make more effective the description of physical principles behind precision engineering (flexure design, tolerance design, thermal stability, accuracy of transducers and measurement devices, etc.) and their relationship with mechanical design, part manufacturing, and assembly. It is also a very effective way of illustrating how many engineering design problems are tightly related with mechanical stiffness, how stiffness is rooted in the design engineering specifications, and how design principles like kinematic constraint impact the product conformance with requirements and specifications.
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