Machine Design Project and Mechanics Education

Abstract

Traditional machine design is essentially applied mechanics and builds upon engineering mechanics topics: strength of materials, statics and dynamics. The current Mechanical Engineering Technology program includes a sequence of mechanics courses leading to the upper level course of Machine Design. Our program emphasizes strong background in computer aided modeling and drafting as well as manufacturing, a combination much appreciated by the employers in the region. Thus our senior class is well prepared for the capstone machine design course which requires not only an electronic design solution but also a prototype. A design group was assigned the design of a beam testing device which would load an instrumented beam in various ways and the results will be measured in terms of stress and deflection. Moreover the group was charged with the task of visualizing this device being used in the junior level strength of materials laboratory class. It would require the student team to conceive, design, model using CAD, analyze, prototype, test and finally develop a set of laboratory experiments. The project will not only train the design team with the design process and modern analysis and simulation tools, but also the mechanics education behind beam loading and resulting stress will be reinforced. Developing the Instructor’s User Manual was also an exercise in thoughtful insight into the mechanics of beams. The completed rig is being used in our Strength of Materials laboratory class which virtually eliminated the 15 feet beam that was used earlier. The test rig made it possible to simulate multiple loading conditions and tested within one lab session which was impossible using the large beams. The design team took special interest and pride in completing this ‘practical’ project. This paper describes the design course, the prerequisite structure, the design project format and expectations, the design and engineering specifications and summary features of the test rig. Limited usability survey data demonstrates the ease and versatility of the new rig compared to the large beam testing setup.