M. Yockey's Final Thoughts

Starting this course I knew absolutely nothing about design and manufacturing so I was always learning something. The machines were very intimidating, and it was amazing how many of them I felt comfortable with by the end of the class. There are two lessons that stand out. One: running a current through the motor, and seeing our machine move the way we planned it, showed me how simple creating movement is. Two: our machine did not function as planned because we were not careful enough with the manufacturing details. The machines that functioned the best had clean, precise layouts. As irritating and unimportant as they may seem, the details make the machine.

Communicating those details is one of the most difficult parts of teamwork. Working on your own you already know what an idea will look like in 3-D, and you just make it. As a group an idea must be repeated 2 or 3 times to insure everyone understands. There were times when people were thinking something very similar, but the language made it sound like two completely different concepts. At least once four people “understood” the concept four separate ways. The more people are involved, the more time must be spent talking about the project before making anything.

Everything takes longer than you think it will. SolidWorks will not do what it is supposed to; the machines are full; that amazing idea does not work with any of the other modules. Something will go wrong, especially when you are a beginner. If something needs to be changed, it might take an extra day to get the group’s okay. It would have been wonderful to have a full week of tinkering and practice time. We could have had that if we spent as much time in the shop the first week it was open as we did during the last week.

My favorite thing that I learned is nobody knows everything. It seems obvious, but there were so many times when I felt like I was the only person doing something for the first time. It makes a person feel like an idiot (perhaps justifiably so). Being in the shop with other people who could admit that they did not know how to use this or that machine made it easier to ask questions, and it made the work more fun.

One change to the course would be to spend less time on the individual design process, and move up the date for the finished machine. The competition was great, but a lab section at the end of the term where groups really have a chance to look at each other’s designs would teach so much. Do something casual without the pressure of a presentation. Have two groups meet at a time per se and have them try to operate the other group’s machine. There was so much discussion at the beginning regarding individual ideas. We needed that discussion at the end once we actually had some experience. Also, please do not do so many last minute additions. My education is important to me, but I do not wish to be tied to my computer waiting for the next update. Technology is wonderful, but people should play outside.

I could have been more focused especially at the beginning of the term. I wish I had had more time for reading since that is how I learn best, especially when I am uncomfortable with how little I know. I would also have moved fewer times.

Alec Lind's Final Documentation

I found ME 250 to be a very fun, interesting, time consuming, and sometimes annoying course. As far as the design side of the course I got a lot more exposure to a CAD system than I ever have had in the past which I really liked. Also I found the lectures to be very interesting (most of the time) and it helped show me new ways that you can do engineering analysis of a system. I felt the use of the FRDPARRC’s was a little excessive at the beginning of the semester. I felt it overly emphasized the structure needed to design something. However, at the same time I understand what the point of the FRDPARRC’s are and the need to think of all aspects of manufacturing and all potential problems when designing your machine.

As far as the manufacturing side of the course I unfortunately do not feel like I learned much at all, which is disappointing. I would have enjoyed it if we had to manufacture a machine with a lot more time put on the mill and on turning parts. The parts on our machine had very minimal use of the mill or the lathe. I had already had exposure to a drill press, band saw, shear, Al. bender, etc. However I have only had some exposure to a mill or lathe and I would have been much more excited if the mill and lathe were a more important part of the manufacturing process. I believe that the only way you can successful design something is if you have a good understanding of the manufacturing end and the machines limitations, so I would have enjoyed a much more manufacturing (mill and lathe) intensive course.

As far as teamwork goes I can’t say I learned much of anything new about teamwork. However my beliefs on teamwork were just reinforced from Eng 100 and other teamwork experiences. The use of a team is vital to make any project run smoother and with less flaws. You can use your teammates as checks if one person makes a mistake the others can catch it. Also you can accomplish tasks much faster within a team because you can split up the work load. The same thing goes for time management. It is always important to keep a schedule and do your best to stick to it. Also you should always plan ahead, that way when something unexpected happens you will have time to fix the problems. In manufacturing something I have always been a firm believer in the rule of pi. You can always expect something to take about 3 times longer than you initially expect.

One other thing that I felt was strange about this course is the schedule for the machine shop safety/training sessions. We were trained in September yet not allowed into the shop until the end of November which seems like a strange timeline for training.

As this is the first semester for the re-vamped ME 250 course I am sure there was a lot more preparation work for the course on the GSI’s and professor’s part than usual. I personally felt that the release of the rules was a little late and the rules were a little too tame. It would have been nice to have a little more freedom on design creativity. Such as the use of pneumatics; however, at the same time the amount of constraints made it more challenging to try and think of creative ways to outwit the arena. Again I understand that this was the first term for this but I still felt that the timeline for returned assignments, posted grades, and announcements at the beginning of the term was un-professional. I feel there should be an extra amount of professionalism because this is a design courses and the design courses are more like the real world situations we will be experiencing then majority of the other courses here at Michigan.

As far as how I would have improved my performance in the course. I would have designed a different type of machine so we would have done better in the contest. Looking back at it I would have designed a less traditional machine. I would have designed a machine with the same strategy as our second machine. It would pick up the heavy ball but then I would have a piece of aluminum lay down over the funnel in the back so I could drive the machine around on the 1’ ledge. Then once it passed the mid line I would park the machine there because none of the designs could reach the extra platform. With the heavy ball on the opponent’s side and off of yours you have an almost guaranteed win. Also I would have tried to stay on the schedule set for the manufacturing side of the course a little bit better. That way we would have had more time to practice and fix problems in our machine.

Justin Faber's Individual Reflection

I learned a lot of very valuable skills in me250 this semester that I know will help me in later in my mechanical engineering education and career. I learned how to use CAD programs to create solid models and detailed drawings of what I’m designing. I also learned how to go from just a drawing or a solid model to a physical part with the machines we were taught to use. I now know how to use a mill and a lathe to fabricate parts with great detail; both of which will be useful in the future. I learned that in design, you must not be afraid to come up with crazy ideas that you can later refine into something more tangible. Teamwork is a very valuable part of design and engineering, especially when you are working on a project that takes a whole semester. It’s nice to be able to divide the work so it doesn’t become overwhelming, and it’s also helpful to have a team because you can collaborate ideas and knowledge. If one or more team members don’t know how to do something, there’s a chance that another member does. It’s also a very good idea not to procrastinate. My team learned a lot about time management throughout the semester. At the beginning of the semester we would do assignments at the last minute, until we realized that it’s very hard to coordinate the schedules of four people to find times to work on things.

I understand this is the first time this course has been taken since it changed. Knowing this, there are definitely some areas that could be improved upon. It would be nice to know the rules of the game a lot earlier and have them clarified and set in stone right away. My first few designs were completely different than my later ones because I misunderstood how the game was played. Also, our designs as a team changed multiple times throughout the semester because we were unclear on some of the rules until close to the end of the term. Another thing that would be helpful would be to make the kit contents available sooner. We also had to change our designs based on finding out that we weren’t given certain materials. The only other way I can think of improving this course would be to not expect so much from the students early in the term. For example, many students hadn’t learned CAD yet and some of the CAD assignments were asking us to do much more than we were taught.

I personally could have done better in me250 by doing a few things. If I hadn’t put off assignments until the last minute early in the term, I could have finished them in a timely manner and done more of a quality job. Also, our machine may have turned out better had I put more effort into the design of our machine outside of class and team meetings. Overall, this was a great course and it was a lot of fun.

Nigel Moore's Individual Weblog

ME250 has been a great experience. I learned much about the design process. I used to feel that it didn’t take any real effort to design something that you already have an idea of what you want that something to do. Then I found out that design something was way more complicated than it looks. There is so much that goes into the design process, like forming strategies, concepts that go along with those strategies, and an idea that would make the chosen concept work. I also learned that once have chosen that said idea, manufacturing it, is a whole different story. You would think it would be easy to just come up a simple plan to follow as you make your machine, however there are so many things that could go wrong with manufacturing the part. If these things do go wrong it could mean a trip back to the drawing board or even worst, scrapping a whole idea.

This is why working with a team is so important. If things do go wrong, you have someone to back you or even someone that could fix the issue. Also having a team makes it easier to go through the design and manufacturing process. Sure you may run into problems with conflicting ideas about the way something should be designed or the way something should be manufactured, but this often leads to a better outcome on the project. Finally working with a team can alleviate some of the stress that comes with designing and manufacturing something. When something doesn’t work with the design or manufacturing, someone from your team could help figure out the problem or already even have a solution to the problem, whereas if your working by yourself, you only have yourself to rely on which can be difficult at times.

I also learned the importance of time management. Waiting until the last minute to make changes in your design can make getting your machine manufactured in time very difficult. This is what happened to us. We had many great ideas at the beginning of the course and sometimes changing those things made the manufacturing process a little bit more difficult than it has to be. Also you have to expect the unexpected. Since there are many things that could go wrong with your design or manufacturing, that time needs to be accounted for in your schedule. Finally, if you are ahead of schedule, you should continue to work at the pace you’re working at. It is better to finish early than to rush to finish on time.

I understand that this was the first time that this course was done the way it was so of course there will be ways to improve this course. The first thing that could be changed is the timing of when the rules for the competition are introduced. We were already going through the design process without knowing the rules, which completely backfired for some of the designs that were already thought up before learning the rules. Also make sure the rules are more concrete. One of our ideas was shot down by something that wasn’t even in the rulebook. Another problem I had with the course was the workload in the beginning of the course. If this was the only course that I had taken this semester it would not have been a problem but the fact that as students, were usually taking more than one course it made the workload seem real heavy. Other than that I had no other problems with the course. Also I could have improved my personal performance in the course by simply not procrastinating as much I did.

Link to final Bill of Materials

Final Bill of Materials

Juggernaut Final Documentation

Our first machine was originally an extendable arm that rotated in the slot of the actual arena through the use of the fixed motor. However since we were only allowed to use a total of four motors, we couldn’t actually make our arm extend because our other machine used three motors and we needed to use the fixed motor. We chose to use the Delrin for our arm because it was lightweight and would be easier for the fixed motor rotate it.

Our second machine was a hopper that dropped down into the slot to pick up the heavy squash ball. Once it picked up the ball, it could come back up because the hopper had a rack and pinion setup. Once the ball was picked up out of the slot, we could drive the machine to the opponent’s side of the arena using the double gearbox setup. The double gearbox allowed for our machine to drive around another machine if that machine blocked the center of the arena. We built the hopper out of wood blocks and the hollowed out quarter inch aluminum stock. We also placed a rubber band at the bottom of it to hold the aluminum stock in place and also hold the squash ball in place once it was picked up.

Video

Here's the video we made introducing our team and explaining our machines.

Almost Competition Time

It's crunch time and all the teams are scrambling to put some finishing touches on their machines. We just finished the final assembling of our machine and today we finally were able to do some testing. We ran into a couple setbacks, finding out that our arm doesnt behave quite as we expected and the hopper machine has a couple problems with the drivetrain which we have to work out before tomorrow. Below are a couple pictures of the team working on the machine.

Our hopper pics

Seeings as it is getting to crunch time and our parts are really starting to all come together. I felt we should post a picture of our hopper which is arguably our second most critical module. The hopper is what goes into the slot after our arm has cleared out all the ping pong balls and picks up the heavier balls. Our hopper in constructed out of al square stock cut to be Al angle stock on the band saw. Then using sqaure wood pieces we made a hopper with a rubberband at the bottom which will deform as it is pressed onto a ball. Then the squash balls will be trapped in the hopper and a planetary motor on the rack will raise the hopper out of the slot. I will post more picture with the rest of our machine in the next few days.

Update on Vehicle in some place other than comment box

It should probably be noted somewhere other than the comments box on our original design post that the design of our first vehicle has changed. To just incorporate an arm which runs off of the fixed axis. This change was made because by making to vehicles we would have had to design our own remote system to control the two vehicles independently also we would have needed more motors than we were allowed. By making this first vehicle just an arm we are within all of the requirements and the same purpose as the original design intent can be used with the new design. The new design is just a fixed arm with a keyed slot for the axle so the axle will rotate as the entire arm rotates when we rotate the fixed motor. The two other pictures are the axle and the other side of the axle which the arm will rotate on. (One update needed to the axle photos is we need another hole in the axle so as to properly constrain the axles together so they will appropriately function as an axle

Original Schedule with updates

We have added an update column for things we plan on doing in the next two weeks for our machines to be completed on time

Remaining To Do list including build process for machine 2

Our to do list is basically the build process for our second machine, b/c that is almost all we have left to do. Also a small additional to do list has been added below the spreadsheet of other tasks we must do.

Another update... and new schedule coming shortly

I don't have any new pictures at this point but when we post our updated schedule there will be more pictures. As far as updates on what we have done. We have our MCM done to the specifications we designed it to however it isn't good enough to be competitive yet so we need to do some modifications to it. The motor which is attached to the underside of the arm (this will make more sense when new pictures are posted, see next batch of pictures for reference) is not constrained will enough and we found the axle tends to wobble and not just rotate which causes the machine on the rack and pinion to skip and thus creating an unreliable machine. So we need to remove the wobble in the shaft and then we suspect our MCM (machine 1) will be fully operational. Also we may try as an extra precautionary measure making our MCM shorter or the shaft taller (making the shaft taller would make constraining the wobble more important). By making the MCM shorter more of the gear will connect with the rack, as it stands now only 3/4 of the gear connects with the rack and if we can get it to 100% that would be better.

As far as an updated schedule we will post a more complete updated schedule soon, however for right now..... WE need to build our second machine which consists mostly of using the band saw the drill press and the waterjet. We will cut our base out with the waterjet and then use the angle iron to cut make axle mounts and the Al rod for the axles. The most difficult task we have left is creating our hopper b/c there is still some disagreement on the best design for the hopper. However once that is figured out our machines should be fully functional and ready to be seeded.

MCM parts update

We have constructed a good deal of the parts for our MCM. We still need to create the axle for out MCM which we plan on using both the mill and lathe for. The axle will have to have two different diameters which is why we will need the lathe and one of the diameters will have flat surfaces on the top and bottom so it fits in the parts shown above. After we have the axle made we just need to assemble our MCM and setup the electronics for it. Which we plan on being done with by the tuesday evening before Thanksgiving break. Our completed MCM will look like the first picture above with an axle attached to it. The MCM will rotate using the externally controlled motor and the arm will slid in and out on another motor. Also by Wednesday before Thanksgiving break we will have the rest of the build order and plan for our other machine completed.

MCM update 2

Below are some screenshots of the parts of our MCM that we plan on fabricating by the end of this week.

MCM update

So far, we have our MCM all figured out as far as dimensions and how everything will fit together. We plan on entering the ME shop this week to start fabricating parts. The three parts we plan on making for friday are the walls of the chassis for the arm and the retractable part of the arm.
We had to re-engineer some of our most critical module due to finding out certain rules and limitations but next week, we will finish designing and fabricating the MCM.

Team Schedule

Link to Juggernauts team schedule

Juggernauts Team Strategy

Our team strategy is to use two separate vehicles. The first vehicle will have an arm which rotates down into the slot and then extends to reach the slots bottom. After the arm is full extended it will rotate and push all of the ping pong balls from one side of the arena to the other. At this point we will keep the location of the arm stationary and it will now act as defense to block our slot. Our other vehicle will drive in behind the first vehicle and use a "tennis ball hopper" design lower a cage down into the slot which will trap the heavier balls in the cage. From there the cage will be raised out of the slot and the vehicle will drive to the opposing teams side.