Julius Roberts' Reflection

I started out the semester second guessing my choice of mechanical engineering. After the first couple weeks of ME 250, I was strongly second guessing my choice of mechanical engineering with the thoughts of, “what am I getting myself into?” As time passed on, my original views began to evolve. This wasn’t until I began to think creatively. But thinking creatively came with some challenges. These challenges lied in the fact that all the material presented in lecture was completely brand new. I had little to no prior knowledge of things such as linkages, gear trains, bushings and bearings, etc. Some of the material sounded familiar but I had little to zero knowledge of the purpose or function. Based on these facts I was very nervous and discouraged about building a machine that made up for most of my grade.

One philosopher stated the mind is a blank a slate and can be molded into anything, well in my case this was true. As stated before, I knew next to nothing about the material in this course, from the purpose of a rack and pinion to how to work a lathe. The course demands a great amount of time and effort. In my opinion, the course should be worth more credits than 4 for how much time out of the classroom is required but this is beyond the point. Starting out with a blank slate it is hard to narrow down exactly what I learned but I’d have to say the most valuable chunk of material I took away from this class is the design process in general. The most important portion of this class is to take a simple idea of collect balls and think of various ways this task can be accomplished. Then, pick one way and think of different ways of how that one way can work and on down the list of the process. In my opinion, the goal of the class is not to see how well you can manufacture a part or how well you can put together a gear box; rather it teaches you to accomplish the desired time-based checkpoints throughout the process.

Growing up I played team sports so naturally I was excited about being part of a team again. I know from experience that teams typically don’t function well if there is any part of the team that does not hold up their own portion of the work. Luckily, in my case this didn’t happen. Our team was pretty well split up in our own special skill sets and all with the same common goal of succeeding. The only problem we encountered within our team was time lost. Our team got along very well and often found ourselves becoming sidetracked, but there was always one of us who pulled the rest of the group off the tangent of Michigan football or quoting a movie. This never affected our overall time schedule, we just found ourselves spending a little extra time on a task for the day. Even though this particular course demanded a lot of work outside the classroom it was a great experience to be responsible for more than just myself but for three others.

In every system there are going to be some flaws especially if that system is on its second walk-thru. If I could only change one thing in this course it would have to be the time schedule of assembling groups. Looking back at it, the individual work done during the first half of the semester was a good experience of thinking critically on your own but was definitely challenging when you didn’t know how things would work. Assembling groups early on would eliminate this confusion by allowing team members to brainstorm ideas together. But that is not the only reason I would move up the date of putting groups together. The second reason is allowing more shop time to be available. If groups are assembled two weeks earlier that means each group has two more weeks to manufacture parts in the shop. During crunch time (the last week of the class) we found it very difficult to access machines. This caused imperfections on some of parts by having to use machines that had greater tolerances. Also, we found ourselves in the lab/shop from morning to evening. This caused stress not only in ME 250 but also in our other courses that had to be neglected. Being able to spread out the manufacturing time would benefit the students immensely.

One way I could have improved my experience in this course is to not rely on my teammates so much on certain aspects of the project. If the time schedule to manufacture wasn’t so tight I would have tried to use the mill but since we didn’t have time to waste two of my teammates mastered the mill while I found myself and another of one of my teammates working solely on the lathe. This would have helped on the examination in putting together the manufacturing plan.

Neil's Reflection

This semester I had the chance to take ME 250. This class was an introduction to engineering, design and manufacturing. Over the course of this semester I learned a great deal about design, analysis and how to operate a mill and lathe. This knowledge will help make me be a better designer and engineer. Knowing the manufacturing process I will be able to design parts so that they will be able to be made with less complications. If my design is not able to be made on a machine I will have the tools to redesign the part so that it is able to be made. After building the bot for ME 250 I have realized and appreciate how much work it actually takes to make a design that is functional and efficient.

ME 250 also taught me how to use CAD. CAD is a very powerful and important aspect of designing and engineering. It helps with putting ideas together and the ability to share it with the rest of your team and co-workers. CAD allows you to see how you much a project will weight, where the center of mass is and where the weak points are in your design. Learning CAD this semester showed me the importance of constraining your sketches and the proper way of making parts in CAD. In addition, it taught me to design a part the same way that it would be manufactured. This way you know that you will be able to build it when you are done designing it.

Our team worked together effectively building the bot this semester. We put in the effort needed to get the project done on time. We were able to divide up different tasks so not all of us were working on the same thing at the same time.

I can improve on not having to redo CAD as many times as we had to do. Also take a closer look at the gear boxes and motors sooner so I would know how strong they are. I would incorporate both of the planetary gear boxes for the turning/driving of the bot around the table. Also take the time to look over the whole kit before I started to design so that I could us as many of the materials in the kit as possible.

Before designing the bot I wish I would have went back over some of the lectures that talked about the gear boxes and motors so that we could have made a more effective design. I would have made the front wheels drive the bot and had a single caster in the back of the bot to keep it level. This would have let our bot move around the table easier.

The course could improve on the training aspect of the mills and lathes. The gap between the training days and the actual machining times was too long. Most of us forgot how to use the machines by the time we got back to them. We had to ask Bob and John too many questions and we weren't effective at machining. Another thing that could be changed is if you let the groups have the kits sooner, they could actually see what they had to use and not just a list online of what they get to use.

Now that I look back on the class I feel like I will be a more effective engineer in the future and hopefully will carry this knowledge to next phase when I take ME 350.

Our Final Machine-Winner of the Simplest Design Award

Our final machine consisted of bot that was about 12" wide, 15" long, and 10" high. The bot was able to drive forward, backwards, left, and right and included a cage that was able to lift up and down to capture balls. The bot was able to drive with the help of a double gearbox and differential. We chose a 48-24 gear combination in our differential. The motor powered the back axles. The cage wall was lifted and lowered with the use of a winch and pulley. Pivot arms were connected to a front cage to allow the up and down and movement. The wall itself was connected to a string which was strung through a pulley tower and then tied to a winch. The winch was coupled to and powered by a planetary gearbox. Our design was able to move and push balls due to the roller concept we implemented. A threaded rod was connected along the bottom, inside of the cage walls. This allowed the balls to roll without trouble.

The bot was made from mostly aluminum, but also included pieces such as the clear plastic plate, plastic wheels, and connecting parts such as nuts and bolts. It was formed from processes such as milling and lathing, and also from processes from the drill press, water jet, and laser cutter. We also hand tapped the holes in the pivot arms, pulley tower, and stopper blocks.

The final machine worked to our design intent, and was able to score during the competition.

Lindsay Cragel's Reflection

            Coming into the semester, I had very little knowledge about manufacturing or design. The initial designs I submitted for the class were impractical, unrealistic, or lacking in important details because of this lack of knowledge. Throughout the semester, with the help of lectures and my teammates, I learned about things that would have made those initial designs much better. I learned, for example, that our cage in the front wouldn’t lift by magic, but could be lifted by either or winch or a rack and pinion. I also learned that a car doesn’t run by just a motor, but with a combination of motors, gearboxes, shafts, and differentials. I learned about how even the simplest of designs have a lot of intricate detailing. Our design as the perfect example won the award for the simplest design, and yet it took a lot of work to make that thing work—and about a million brackets. The best part about knowing nothing at the beginning was that I was able to leave having learned so much. After learning about the basic principles of design and about manufacturing in this class, my future designs will be much better. I now know that solid understandings of the basics of manufacturing are essential for any kind of design. My new found knowledge of how things work and how they fit together will prove to be very useful in my engineering career, and I look forward to growing in that knowledge.

            This project experience taught me about more than design, however. I have had experience working in teams before, but never like this. We had to communicate on a very regular basis, which meant that everyone including myself had to improve on our abilities to understand and share ideas. We all to be able to not only receive and handle criticism, but it was also essential that we learn to dissect, analyze, and give constructive critics to those sharing on our project. Along with sharing our ideas, we also had to share our time and energy. Being on a timed schedule, it was very important that everyone in the group put in an equal amount of time and work towards the end goal. We had to communicate about availabilities, and daily objectives. It was important for the group to utilize and balance ability. We found that if one group member lacked ability in one area, they would compensate for that in another area. For example, I lacked machining experience but would make up for it by organizing the team’s schedule and handling the team’s blog. Our team had to learn to organize, which I think we adapted to well.

            In addition to learning about how to build a machine and how to build it while working in a group, I also learned quite a bit from having experienced the competition. Participating in the competition helped me to realize a lot of flaws in our design. For instance, the size of our bot wasn’t realized to be a problem until we learned how hard it was to turn it or move around our opponents. What this helped me to understand better was the need to really consider all possibilities and objectives of a project before formulating a design. In future projects, I would take more time to research before designing.

            As far as course improvements go, there should be many. I will say that as it this only the second year of the professor’s career, the flaws are understandable. I felt it was a bit disorganized at times, with the order of assignments and layout of the class. I understand and can appreciate the thought process behind the layout—with everything taking up one third of the class—but in the end, this wasted a lot of time. I feel, and I know most of the class agrees with me, that we should have been put into groups much sooner. It was a waste of time for everyone to design and revise, and revise again our ideas just for us to come up with new ideas once we were placed into groups. Another thing that I can appreciate but would probably change were some of the assignments. I understand the importance of creativity in design, but honestly those assignments were useless. Who cares what my mass is as the size of a ping-pong ball? My efforts could have been used in something more useful. I would also have liked to not only learn about what a bevel gear is, for example, but also to maybe have some assignments that helped me learn about the uses of the components we discussed.

            In regards to how I could have improved, I wish I taken more time to learn about how different mechanical components work and what their uses are. I would have been of more use during the design stage if I had done this, and maybe our design could have been better. And, I wish I had started studying for that test sooner.

            All in all, this was my favorite class. As much as we struggled and worked, I loved learning and manufacturing. Can’t wait for 350 with Umbriac!! : ]

Personal Reflection

By: Ryan Doherty

This term I took part in the course ME250 at the University of Michigan. This course was designed to introduce the engineering ethics of design and manufacturing. During this course, I was included in a team of four that constructed a project that was to perform and deliver a required set of goals that were to be oriented into a competition amongst the other teams throughout the class. During this process I learned about design, manufacturing, teamwork, and time management along with other quality assets.

In this class, I learned a great deal about Solid Works. I was familiar with NX software so it was easier to pick up on the new additions that Solid Works has to offer. I found it easier to use and more ergonomic. I learned how to create parts such as rods with holes and grooves, buckets, and plates with ease. I also learned how to create somewhat complex parts with the software, including bearings, gears, and springs. Creating the assembly was also easy to do when you upload the files into the window. Our group was pretty good with completing the required amount of design models for the milestones that were assigned.

After the machine was designed using Solid Works, we used the software to make drawings for each part in order for us to assemble the machine with the materials that were given to us in the project kit. I had previous experience before this class with using the lathe, and among other machines in the shop, but definitely increased my personal skill with all of the equipment. I also learned a lot about using the mill, which I have never used before this class and was happy to be able to get some experience using the machine. Good engineering practice was a big thing that I learned throughout the course, such as zeroing and turning surfaces in order to get a correct read on the measurement, and even with small things such as putting washers on bolts so you don’t wear or damage the material that you are fastening. This class definitely made me think more about the ways things work and how to solve problems that occurred during the stages of production.

Even though there were a few bumps in the road along the way, none of this project would have went nearly as smooth as it did without the help of teamwork. Without everybody’s input about different aspects of the machine, it would have taken a lot longer to produce the outcome of finishing the machine with it full functionality. I have worked in teams throughout my life in many different classes, sports, and work environments, but this class immensely helped me improve my skills to work with people that I did not know prior to the team assembly. The people in my team helped me with developing my habits of time management, for they greatly improved throughout the course of the term with getting a vast amount of work done in a somewhat small time frame for deadlines and due dates.

Although I would say this was my favorite class that I took this semester, I would have to admit that there is much room for improvement to make the course better. My advice would be to start the term with the introduction to Solid Works to get everybody familiar with the materials that they will be using. I would also suggest assembling the teams much earlier as in after the first week. This would help people learn together and add a lot of time for working on the project in the end of the term. I feel that the first few weeks were unnecessary to participate alone. The assignments were fine and could still be assigned to work on individually, but the milestones about the design processes should have been in teams the whole time. It felt that much of the material was overlapped in the milestones after teams were assembled, since we had to completely revise the way we made the machine to get everybody on the same page. Doing this would help give teams much more time to fabricate their machine and get it running the way they intended in time for the competition. My team was able to finish making our machine but ran short of time for practice running it, while I heard other teams were having much more trouble and could not get everything completed as necessary for milestone nine.

I personally could have improved my performance throughout the course. In the beginning, I was not very organized and missed some points on the milestones due to not enough attention to detail. I missed simple things like writing a paragraph on which module I thought was the best and why. I could also have better prepared myself for the assignments for I underestimated them and forced myself to crunch time in order to complete them, for the first two anyway. But all in all I thought that this was a very interesting class and I am very excited to see what I am able to accomplish in ME350.

Promo Video

The Team. The Machine. The Hunt. The Kill.

THE HIT LIST.

Final Bill of Materials

Here the link to our final bill of materials:

https://spreadsheets2.google.com/ccc?key=tm6TosOqiMLhFg-2JDcz02A#gid=0