Individual Reflection by Eugene Ho

As a computer engineering senior, it was both an exciting and intimidating experience taking a mechanical engineering design class. While taking the Engr100 class during my freshman year, I discovered the usefulness of knowing how to produce CAD drawings. CAD drawings presented an elegant and effective way to communicate model/machine ideas to an audience. Inspired by that, I wanted to learn more about CAD drawings and hence decided to take ME 250: Design and Manufacturing I as my flexible technical elective class.

To this end, this course had proved extremely beneficial. In the very first CAD lesson we were taught basic Solidworks commands like the various views and zooming, measuring and panning. Subsequently we learned sketching and drawing commands such as extrusion, revolution, fillets and chamfers. Finally we were taught to create engineering drawings which were essential in communicating the specifics of our components to other engineers and machinists. Throughout this period, we were given CAD assignments weekly to help us grasp the commands better and put our new skills to the test. This certainly gave us a chance to practice what we learned in class. However, the workload was sometimes very heavy, especially when we had the regular and strategy homework due in the same week. I feel that the homework could alternate between weeks, i.e. CAD assignments every 2 weeks (covering 2 weeks’ worth of lessons) and regular/strategy homework every other week. The quality of the CAD assignments was good as it tested us on a variety of drawing commands. The regular homework (Introduction to materials and Bicycle) were rather challenging for a non-ME major like myself. With only high school physics background, I had trouble understanding and solving all the questions. Fortunately, my teammates were very patient in explaining the required concepts and Office Hours with Sam helped too. However I feel that the focus of this class should not be so much on complex problem solving than on “design” and “manufacturing”.

The manufacturing part of this class was a real eye-opener for me. Being a hands-on person at home, I have used many power tools in the past and love getting my hands dirty building a dog shed or fixing up a new cupboard. Even so, I was introduced to many new manufacturing processes such as milling and lathing. I also learned how to tap holes, laser-cut plastics and water-jet thin sheets of aluminum. The staff in the machine shop were really friendly and always ready to help us. Manufacturing can be tricky, and sometimes a slight misjudgment could cost us precious machine shop time as we would have to re-manufacture a particular component. I realized that it is always important to check, and double check our engineering drawings and specifications before manufacturing the different components. For example, we overlooked the zoom level (aspect ratio) in the engineering drawing for our machine's guide rails and ended up water-jetting half its intended size. We were able to correct our mistake on the spot and make a new piece with the correct dimensions. This is an area where I could improve my performance in the course, by learning to be more meticulous and careful. It will certainly help save time and effort.

Over the course of this class, teamwork was key to meeting project deadlines and producing a successful machine. While there were inevitable disagreements amongst us when it came to design principles and strategies, we were able to compromise and stay focused on our goals and objectives. This is evident in our team “Brute Forcier” seeded 6th and advancing into the 2nd round of the competition. Time management was critical too, especially towards the end when several rounds of testing revealed flaws in our machine. We had to come up with solutions quickly to fix those problems. We finally had our machine working just 2 days before the competition date.

Overall, I had no regrets taking this class. While the amount of workload could be made less heavy, I graduated from this class with an appreciation for the complexity and effort that goes into every design and manufacturing process. Of course, I also met my original objective of learning CAD drawing. I would like to thank Professor John Hart, Mark, Sejin, Jean and my teammates for this great experience.