Individual Reflection- Calvin Chiu

            ME 250 was definitely one of the more interesting classes that I have taken at The University of Michigan thus far. It was the first class that allowed me to take advantage of real design and manufacturing, which is something that I have always been fond of since a little child. If I had to describe design and manufacturing (in general), I would say that it all boils down to creativity, time management, and simplicity.

            The design aspect of the course caught me off guard because I have never used any sort of computer-aided design modeling in my life before, so using SolidWorks was a change for me. It really tests your ability to creatively come up with an idea that can physically be manufactured, as opposed to a wild one that isn’t exactly feasible. Then, taking those ideas and refining them down to modules was something else that was new to me. I had never done this before so being able to do so now proved a worthy experience for me.

            Manufacturing parts was also a new experience for me. We learned how to use most of the machines in the Mechanical Engineering Machine Shop, and then we were allowed to use them to manufacture our own parts. Manufacturing our own parts made me realize that designing a part isn’t about how complex a part is, but rather about how efficient you can be with the simplest design. I learned that simplicity is key because the more complex a part is, the more ways it can malfunction and fail.

            Teamwork on a project like this was entirely new to me. I feel like I definitely benefited from this course because it taught me valuable lessons in regards to being a part of a team. Everyone has a shared responsibility, so everyone is expected to carry his or her own weight throughout the project. As far as time management goes, this course showed me that working around peoples’ schedules is extremely tough because everybody has different things going on at different times. It is extremely important to organize set meeting dates every week as opposed to winging it every week. Our team had issues with meetings at first, but once we laid the hammer down and organized set times, we flowed a lot better towards the end (except for the actual end).

            The end of the course proved to be one of the busiest time crunches I have ever experienced. There was just too much work to be done in too short of a time, but we somehow managed to complete our robot.

            To be honest, there are too many ways in which this course can be improved. First of all, the task of having an inexperienced team design a robot and manufacture it from scratch within 3 months is just too tough to be done (Unless the robot design is very simple and requires little work). There really isn’t any way to make this aspect of it easier. Also, a lot of the lectures proved useless to me, especially the ones about hole sizing and etc. The information provided to us was just too difficult to absorb mainly because I feel as if we had no basis to build the information off of. It was just free-floating information, so as a result, I did not retain much of it. A lot of the lessons I learned were through experience, not lecture information. Also, some deadlines were too ridiculous. For example, one of the final Milestone assignments where we had to go from having 50% of our MCM’s done to nearly 100% of our MCM’s done over break (within 2 working days) was absolutely ridiculous. The grading for these Milestones proved to be too harsh, so I feel as if these assignments should either be worth less, or should be omitted entirely. On top of that, the shop times weren’t very convenient for our team (and many others as far as I know). The shop should definitely be open later because a lot of people still have class during current peak machining times, and as a result a lot of teams don’t get to register for shop time because of it.

            Personally, there is a lot that I could have done better to improve my performance on this team. For one, I should have studied a little harder for the midterm. Although I feel as if the time constraint on the midterm was inane, there is much more I could have reviewed prior to taking it. Also, I should have managed my time better for team meetings; that definitely would have made a difference. There are also other ways I could have improved my score but were not under my discretion. If we had later shop times, then I could have made more towards the beginning because my schedule often didn’t free up until after 6 or 7 on most days (4 out of 5 weekdays). I would highly suggest that any student who plans on taking this course should reconsider his or her schedule before committing to this class. For a 200 level course this class was definitely too much of a time commitment. 

Noah's Final Reflection

In ME 250 this semester, we were immersed in the world of design and manufacturing from day one. We learned all there is to know about mechanical components, the design process, SolidWorks, and plenty other areas of the Mechanical Engineering world. Specifically, we learned how to develop an appropriate design, starting with the development of a strategy, then coming up with appropriate concepts to implement said strategy, and then finally how to create modules for those concepts in order to successfully complete a task. Secondly, I learned a lot about time management from this course. Our team started off a little shaky in the organizational category, but we pulled our act together once the deadline approached and were able to learn what it takes to manage a group, organize meetings, and successfully achieve desired results at each meeting. After an internship this summer, I learned that being able to work with a team is probably the most valuable skill to have in the workplace. It allows for seamless meetings and creates an environment for people to get work done in an efficient manner. Overall, I am happy that I took this course, even though it was an incredible amount of work.

In terms of the class, I felt that the workload was a large amount, and it was very top heavy towards the end of the semester. With this, and being a Computer Engineering senior taking the course for fun, I found that the work being mostly towards the end of the semester made it very difficult to focus on all of my classes. I found myself putting much more time towards this class than anything else and I had hoped to not have to do that. Fortunately it paid off and my team completed our robot in time. But that being said, I believe that this class could be improved in many ways. I believe that from the beginning the workload should be stressed. I think that having the labs reorganized would also be of great benefit. I found that the bike lab had nothing to do with design and manufacturing, nor did it help in any way when working on our robot. More so, I believe that creating drawings of the parts and coming up with successful manufacturing plans should be more stressed because it is very hard to get things approved late in the semester. Secondly, I think that there should be more deadlines with the project early on. It was very unreasonable for us to have to go from 50% completed on the MCM to 90% of the manufacturing completed within two days of shop time. For a 200 level class, the amount of work that you have to schedule outside of class just for meetings with GSIs is a bit much. Which leads to another point, being that for students who have class Monday through Friday, most of which being other engineering courses, it is very hard to find 2 hour blocks in schedules to get into the machine shop. Our team struggled with this for a while and I believe a reasonable solution to this is to have the shop either open later in the evenings earlier in the semester, as well as open on the weekends. It appeals much more to the students taking the class, rather than the professors and guys in the shop, which a class should be about. My final point though is that communication was often very lacking, especially for our team when we had parts that we relied on using the water jet to manufacture and it not being communicated that it hasn’t worked well this semester, and is extremely under-staffed. This almost ruined our project because our driving portion needed the water jet in order to insure accuracy.

Ultimately though, I could have done better through delegating more as the team captain, planning shop time earlier, and going to lecture more frequently. Though I must admit that I put in a huge amount of time for this course and do not feel like I gained as much from this course as you would expect for the amount of time I put in. It was a good semester, but I caution anyone taking ME250 in the future to be prepared for one of the most demanding courses offered at the school.

Individual Reflection - Joe

It seems like the purpose of ME 250 is to immerse you in various aspects of engineering to teach you a lot really fast, and I feel like that happened.

Prior to this class I had no experience in design nor manufacturing. I've worked on teams before obviously but this was only my second experience with an engineering team project.

As far as designing, I learned about the nuts and bolts of designing, i.e. how to sketch and then draw your designs by hand, how to model them using computer software. I also learned that you should try to keep designs simple, which I'll talk about more later. I learned the process of designing a product, from start to finish. The whole idea of starting with broad ideas and narrowing down to concepts, modules, etc. I'm glad that this was taught so clearly because I know somebody who bombed a job interview when he answered a question wrong about the process of designing a product.

Manufacturing, obviously I learned how to use all of the machines in the shop and create parts within tolerances. I learned about trying to think of ways to design parts for manufacturability to. This is one benefit of doing both things back to back in one class. If you design a part that's hard to make, you realize right away because YOU have to make it. Then you learn from it and adjust next time.

For team work, I learned that it's best to create rigid meeting times and plan things specifically. We're all pretty busy now and that was one of the biggest hurdles to get over. Once we set up a specific meeting time and used that to plan, we had a lot more success. For time management, I don't think any of us realized how much time it would take for a project of this magnitude. Now that we've done this and made a lot of mistakes, we'll be more prepared for the next project like this.

As far as how the course could be improved, I feel like immersing everyone in Design and Manufacturing at the same time might have some drawbacks. I learned a lot but I can tell a lot of small details didn't sink in, e.g. which precedence of lines, holes sizing, etc. This might have already been taken into consideration but I wanted to raise the point anyway. 

Additionally, I think that the class time commitment isn't apparent from the beginning. None of us were ready for how much work this required, it's much more than any other 4 credit class. I was talking to someone in another group and she and I both said we skipped a lot of classes throughout the semester to make meetings for ME 250 milestones, and even more towards the end of the semester, and that didn't really seem fair.

Finally, the Milestone deadlines should be changed. It felt like we were on track for the first few (MCM, 3 manufactured parts, all engineering), but then all of the sudden we needed to have our machine 90% done and it was a total scramble. I think if the process of designing the vehicle starts a little earlier, and there would be more time between the 3 parts deadline and 90%. Or the earlier deadlines should ask for more to be done earlier.

There are two big ways that I think our team could have done better in class. One is trying to trim some of the fat out of our design. Mark and Bob in the shop commented that it seemed like we had a lot of parts compared to other groups, and I started to realize that as well. If we had tried to design a body that consisted of fewer parts, we would have finished sooner. Since we had so many things, our design was delayed because we had to build parts, check for compatibility, then finalize designs for other parts and make them. It would have helped to pick a simpler strategy too. The other thing was time management, we should have started making concrete plans a lot sooner and gotten parts made sooner. 

Individual Reflection - Tyler

Upon taking ME 250, I have learned a lot about the Design and Manufacturing Process and working in groups with my peers. I have a better understanding of the actual processes entailed in thinking up and creating the parts and modules needed for your ideas. ME 250 allowed us to have firsthand experience in machine shop work and metallurgy involved in shaping raw metals and minor materials into a concept, like an automated machine, to help solve a problem. Here on Team Power Serge, the guys really learned a lot about each other’s work habits, abilities, and how to implement the guidance of Professors Hart and Umbriac as well as our GSI, Serge.

The first major step for the team was to come up with a strategy and concept that would effectively achieve the goal of collecting balls on the ball tower arena. This was the first major team work and decision based aspect for our team. We wanted a machine that would be different from the others, be versatile in design, and would effectively achieve our goal of capturing the balls. We came up with the idea of a machine that would be able to pull the ball tower to the hole on one side of the arena, and if need be collect balls on the course. With an idea in mind, we then got into the real meat of the class in having to design our robot, figure out how to build it with the given materials, and successfully manufacture it.

The course aspects of Design and manufacturing work are where I feel that I made the most strides and progress. I have a better understanding of how to make the CAD drawings and approval drawings needed in order to tool parts in the first place. Working with the other Power Serge team members to get these drawings made and approved helped me gain additional knowledge and understanding on when in the field an engineer would have to get a drawing made and approved before the metal is even touched. There will be instances where your drawings will be denied or altered time and again before it meets specifications or design approval. When dimensioning holes, it is best to create a single datum and create your dimensions from there.

Once our drawings were approved and in the shop, we were versed in the use of the mill, lathe, hack saw, and other elementary machine shop tools. The team realized that time management was a major aspect in getting our project finished on time. The bot itself was quite complicated, with tank treads, a paddle wheel  and rotating hook arms. We were able to finish the robot and initially get it to work, but we saw great disappointment in the competition when the drive shafts were not fully attached to the tank driven wheels and the bot was not able to move.

In hindsight, I see a lot of places that the team could have improved in completing the project. Time management was a major factor in completing our assignment. Had we done more planning and building in earlier phases of the class, we would not have had to rush in the end. We also had issues in the sizes of some of our bearings, and in adjusting to these miscalculations our drive shafts were affected. Overall the class was definitely a learning experience. We learned how to adjust our schedules and coordinate with each other and other groups to get the job done. Although we did not come in first place, Team Power Serge definitely took giant leaps in the ME 250 Design and Manufacturing I course.

Final Team Post

Now that we're a few days past the competition, we're evaluating how it turned out.

Overall we realized that it was going to be a crunch to finish it in time, and spent long hours in the shop working on it, but were able to complete all of the parts in time for the deadlines.

Here is an image of our whole vehicle with everything attached except the tank treads.

Out of our 3 major modules, 2 worked.

The major failure, or the most apparent, was in the driving wheels. A lot of things went well about this: all of the shaft holes lined up, the drive wheel layout had the right dimensions to keep the tank treads in tension. The major problem was that the shafts did not attach to the wheels. The driveshafts were hexagonal and the wheels had a hexagonal slot. By design, torque should have transferred and they could have worked. Our failure was in ordering the wrong size bearing. The shafts did not fit, so we had to make them smaller. We thought we would be able to glue the shafts in to the wheels, but that did not work. Were it not for that one tiny detail, the wheels would have worked.

The paddle wheel turned out okay. We failed to consider a few things in designing it. First, we assumed that since it didn't need to carry a large load, we didn't need a high gear ratio. But as a result, it spun a little too fast and we had to be careful when using it. We also could have secured it from translating horizontally a little bit better. It did stay in place, but if you ran the motor really fast (which you shouldn't anyway), the gears would disengage. Overall though, it did work and was able to collect and dispense balls.

The biggest success was our MCM, the swinging hook arms. We made a homemade drive belt to work with the extra drive wheels from our tank tread set in transmitting the torque to the rotation shaft. It meshed properly with the teeth on the wheels and worked very well, thus the arm moved as intended. The arm also swung perfectly in the geometry we wanted it to, not swinging two far or tilting improperly at all.

Here is a link to our full bill of materials, including the cost of extra materials we purchased during the project

Group Video

After manufacturing our robot, our team was to make a short video introducing the team members and the robot. We showed the components of our robot, demonstrated their functionality, and showed a sped up cut of our machine assembly.

Approaching closer to the end

     Yesterday was one of the last trips to the shop we will be making prior to the competition which will be held on Thursday, December 6th at the College of Engineering Design Expo. We drilled larger holes in the tube stocks to accomodate the flywheel axle bearings. Along with that, our tiny 2.5mm diameter driveshaft bearings came in the mail! However, it turned out that the 0.04mm difference in size between the bearings and the driveshaft (2.54mm diameter) prevented us from fitting the bearings over the driveshaft. Suggestions have been flying around to either file down the driveshaft or leave the driveshaft in a freezer in order to subject it to thermal contraction. We're not sure what implications the freezing would have after the driveshaft warms up, especially since the bearings are very delicate and would most likely break under any sort of pressure.
     The only thing left to do now is waterjet the rest of our parts and finish assembling our robot...

Approaching the End

With less than one week remaining until the Balltower 3 competition, our efforts in creating a competitive robot design are coming to an end quickly. We have been in the shop everyday this week and it looks like it will be a crunch in the final days of preparation. Today we created a document that has a remaining to do list of all final items that will guarantee the completion of our robot. You can see the mockup of our robot below and we are looking forward to finishing up and hopefully we can successfully complete our strategy during the competition. Get ready teams!

Shop Work

In recent times, the Serging Sophisticates have been in the lab and machine shop constantly working on the machine and making improvements when need be. We are learning to become comfortable with, and use the Mill, Lathe, and Laser Cutting Device. With a box shaped radio controlled automaton, we have been using the Mill more than anything.

The mill has proven to be a very important tool in machining our device. We have been able to use it to create our MCM hooks, side panels, and other pieces along the way. We have also taken a lot of advice from Bob and Mark in the machine shop in operating the machines and figuring out the most efficient ways to make parts. The machine should come out well.

Weekly Meetings, Planning

One of the problems we noticed in our early team meetings, there were frequent time conflicts, with at least one person having to leave early or come late every time. We decided to put our feet down collectively and set a time for us all to commit to being at each week, Sunday 2:30-4:30.

We've done this for the past few weeks and had pretty good success with our planning. Two things that came out of this were (1) creating to-do lists for our lab section the following day, which has allowed us to better utilize our lab time on Mondays, and (2) being able to sign up for shop time better.

Another planning measure we've taken is making our own form of a Doodle using a Google Spreadsheet, to figure out when the most people can get in for shop time. That way we can know what shop times work for us and sign up as soon as they open. The last two weeks we've used this to have somebody doing something on the project almost every day.

Start of Robot Manufacturing

So this week Team Power Serge started manufacturing components for our MCM, our pulling hooks. We spent a few hours on the mill with some tube stock and angle stock. By Wednesday of next week, 11/14/2012, Power Serge should have our MCM fully manufactured. On another positive note, since the exam for 250 is now over, our team should have more time to focus solely on the manufacturing of our robot and preparing for competition. More pictures and progress to come soon.

Team Schedule

Hey guys, this is PowerSerge's second blog post. We have linked the team schedule below so that you can see how we plan to utilize the rest of the semester to complete our project.

Team Schedule

First Post: Strategy and Concept

Greetings all! Welcome to team Power Serge's blog. It is a couple weeks after the Major Design Review and our team is ready to start manufacturing the pieces to our robot. Our strategy for winning Balltower-3 is to use our robot to pull the tower over our hole, then upon completion we will go and block the opponent's hole. In order to do this, our machine concept will have hooks attached to the front of the robot to grip the tower, a paddle wheel to collect balls if need be, and treads to provide the needed traction for pulling the tower. These modules will all be combined in a compact but robust robot in order for team Power Serge to Serge to victory.

3D Sketch Model

3D CAD Model