Trevor's Reflection

This class for me really could not compare to any other class I have ever taken. It was not the same sort of book-study, knowledge based class I am used to, but rather an actual application of all the engineering techniques we've learned. It reminded me a lot of FIRST robotics (which I competed on in high school). As such, it was a VERY enjoyable class, and an educational experience. I felt as though I got a glimpse of what "real world" engineering is, and can see what a potential career path in Mechanical Engineering would be like as a result of this class.

Two things in particular were very enjoyable for me. The first one was the CAD phase of the project. Due to prior experience with Solidworks, and even certification, I was able to jump right in to the CAD designing! I felt as though I had all the know-how about part-naming conventions, drawing templates, and other fine details of the Solidworks software, and was excited to put them to use. I did not expect to learn anything new about CAD at this point, but was surprised when I started discovering new things about using CAD for design, and how to coordinate large-scale projects with plenty of files and subfolders. I emerged from this experience far more comfortable with Solidworks than I had thought I would! My other favorite thing about this class was watching the project come together. It's one thing to see a 3D model on a computer, but its entirely different to see it actually come to life before your eyes! The process of watching all of these parts become a reality, and seeing the final product, is an incredible thing to witness. It is because of this that I think I really want to become a professional Engineer! Our final product was nearly exactly what we had all looked at on the computer screen a month or so earlier, but it was interesting to see the little modifications that we had made along the way. For example, we added a bearing to hold the screw on our linkage system in place, added a limit switch on the conveyor system to direct constant power to our planetary motor, and designed and machined a new part to mount our rack-and-pinion lowering system.

Working in a group on such a long-term, large-scale project was definitely an interesting experience, that I think we all benefited from. One interesting thing to watch was that our design was constantly changing in completely unexpected ways during the first month or so of the class. Our final design, safe to say, was not what any of us had initially imagined. While coordinating with other people on the design can be difficult at times, it leads to new, innovative ideas from all members of the team, that when brought together, result in a far greater and more efficient design than any of us could have concocted individually! Anyway, we all put in a lot of work to this project, from start to finish. At the start of the term, we had great communication and planning, and worked very cohesively together. While this became a little more disorganized towards the end of the term, I still look at our team as a whole and see an overall hard working, cohesive group of people. I feel that I especially put in a lot of work to the CAD and designing phase, but not as much in the machining and assembling. Overall I would like to think I was a valuable member of the team, and I think that my group members enjoyed working with me, as I have with them.

I think the class is a HUGE asset to students who are studying to become engineers. Having a large-scale group project like this in order to design and build a machine from scratch is necessary in order to train new engineers. However, I really thought this class could have been planned out a little better. I would have preferred to have split into groups sooner in the class, for several reasons. A lot of the initial concept work and designing was repeated after we split into groups, which ended up wasting time. Also, by having to share all of our ideas and designs with the whole class for the first several weeks, I felt like most people ended up with very similar strategies. I also would have allowed more machine time, perhaps by splitting into groups and starting the whole project earlier, because a lot of people were crunched for time in this phase.

Finally, I want to briefly address the lectures. I personally did not feel like I gained nearly as much from the lectures as from the project. However, the lectures were designed to teach basic concepts, that many engineers have not yet been exposed to, whereas I felt as though I had been exposed to most of it before. Unfortunately I don't see any way to run lectures aside from teaching the basics of all the topics for this class, but my one recommendation would be to condense the information in the lectures. There were far too many slides for too little of information, and it felt confusing and chaotic at times. But all in all, it was a great class, I learned a lot, and I am glad for the experience! I had awesome group members, amazing GSIs, and apparently a sweet design that won us the "Best Mechanical Design" award! :)

Colin Menapace

Individual Reflection

This semester I really felt that I learned a lot of useful information in ME 250. It was a great sophomore mechanical engineering class because it allowed students to get a ton of hands on design and manufacturing work outside of the classroom. Before taking this class I had an extremely limited amount of CAD experience and this class really allowed me to learn a lot and allowed me to spend enough time using the software on my own to become comfortable with it. Although I thought the actually labs that were planned for Solidworks could have been organized a bit more efficiently. They had a ton of information in them, but the way the labs were arranged made it so the GSI had to be constantly rushing to attempt to complete the lab. And although many students had prior experience and were able to breeze through much of the lab, others needed a lot of time and some individual attention which made classes extremely hectic. That being said I thought our GSI, Davor, did a really incredible job trying to meet everyone’s needs equally and keep everyone on track. If the labs were made to be slightly shorter and the pdf’s were arranged in a more organized style I think these labs could be extremely helpful. It would also be extremely helpful if the class would be broken into teams a week or two sooner to allow teams to use this lab time to being constructing their designs while still participating in the lab. This would allow team members to help each other instead of the GSI’s trying to pay attention to twenty computer screens at once. These lab periods were very helpful to me and I was able to learn a lot of useful and constructive skills. Learning how to design parts and complete assemblies made constructing and testing our machine so much easier and we couldn’t of compiled all our ideas and designs without it.

Lectures in this class were also very helpful in teaching the steps of the design process and the characteristics of many of the standard materials that we used in this class. This class was really great because it allowed us to use many different and unique mechanical devices in our machines which then resulted in a wide variety of designs. The lectures were very helpful in supplying us with the background information necessary to then plan out and calculate designs using these features. The lectures on things such as springs, screws, bushings, bearings, and pulleys were very helpful in sparking our creative mind during the design process. Although I thought many of these lectures could have been condensed to allow for more time in the manufacturing process. Or this stage could have been arranged slightly different to allow us to work with these components as at team as the instructors were demonstrating them.

The manufacturing portion of this class was possibly the most educational and informative portion of the entire class. Being able to get into the machine shop and work as a team on all the parts that we have designed ourselves really allowed us to learn through experience which for me is always the most efficient way of learning. Nothing replaces the experience of actually making the part and positioning it on your device, then realizing some slight modifications need to be made. And this experience in the shop really allows us to work through the problem solving processes of being an engineer and working with a design team. When the team would hit a snag we were able to meet up and discuss the problem and the best and most efficient solution to our problem. The machine shop instructors were also very helpful. It was great being able to think about the manufacturing processes that were at your disposal and being able to discuss this process with an instructor to get his suggestions and learn some of the tricks of the trade that they have acquired over the years. Jon and Bob seem extremely experienced and professional almost always have a helpful suggestion on the perfect way to conduct different machining operations. If lectures could be condensed to allow us two or three more manufacturing periods with Bob and Jon it would be really helpful in planning our designs.

As a whole I thought our team worked extremely well over the course of the semester. Being able to work as a team was very helpful and interesting because it gave the class more of a real world design feel. We had to consider the ideas and abilities of the entire group and work out team conflicts. This gave the project a company-like feel and will be very helpful in our futures as engineers.

Ryan's Reflection

ME250 turned out to be a lot more work than I initially expected.  It was very stressful at times, very fun at others, but overall an extremely rewarding experience.  I learned that I can function on almost no sleep over 4 days, but my friends start to get annoyed by my bad sense of humor.  I also learned that tolerances really, really, REALLY suck.  Plastic gears are now something I have nightmares about.  I know what time the shop closes, what time it opens, and I’ve seen how fast the clock moves when I have a deadline to meet.  I know when my part on the lathe is spinning wrong that I’m going to have to start over again.  I know that to tap a ¼’’ hole to ¼ 20, I can’t drill it with a 1/4’’ drill bit and expect it to work.  I learned too late that the entire lecture series was posted online, and I finally  learned what it felt like to be accused of blogging too much.  I learned drawings cannot ever be dimensioned correctly, and GSIs are actually pretty helpful if you’re nice to them.  And those are only the tip of the iceberg consisting useful things I learned in this course.

                What I learned about actual design and manufacturing?  Well I will admit I learned a lot even if it’s not the first thing that I want to brag about.  The whole initial design process was pretty sweet, and the huge collection of ideas was pretty crazy.  I must say I really enjoyed the lectures on how people think, and adapting to have the best creative process.  Design was pretty relaxed, more so than any other part of the course and it almost put me off guard for the manufacturing.  Yes, the manufacturing, the most time crunched portion of my entire life with the exception of a few other times for effect.  I did learn how to make stuff, and stuff I did make in any way possible-  mill, lathe, hack-saw, a lot of filling, and even a bit of precision drill pressing.  I learned all the names of parts and tools, and when I forgot them I affectionately referred to them as the “thing to the thingy” or some sort of similar variation coupled with some vague hand motions.  I usually got my point across. 

                I like to think that my team liked me, I mean, they laughed at my jokes most of the time.  Once they even told me I needed to remake a part without swearing, which was pretty nice of them.  I find you really hit this time, somewhere well beyond 30 hours of no sleep that I classify as “building character/ bonding time” and since we hit that more than once, I’d say that we did alright.  Everyone’s still alive right?  As for time management, that kind of gets tossed out the window.  Our time management consisted of, “is the shop open?”, “we still have stuff to do…”, and finally the very misleading “we are almost done!”.   In all reality we stuck to our schedule pretty good, but there came a point when the shop hours/other teams in the shop wouldn’t allow us to get everything done as quickly as we’d have liked. 

                This course wasn’t very well planned in all honesty.  Time wise, way too much time was spent playing around with the design stuff, and the jump to actually making stuff wasn’t even close to being soon enough.  The game was really over the top, which led to a lot of teams failing to even score a ball, very boring and a bad taste to those who put in all the long hours.  The shop needs more machines, more space, and better tools (new stuff anyone? Please?).  The ME250 shop was more like a MEeveryone shop with the other classes doing their stuff there too.  The only good thing about the shop was John and Bob, they are really lifesavers.  Also I’ll give a hand to the GSI’s they were the best crew I’ve seen and were really helpful.  The same however, cannot be said for the lecturers.  They were really good lectures, but pretty much faded out of the picture and I only saw them in the shop  once or twice.  Maybe it was just the second year blues, but this class was a ton of work.  However, that said, I’d take it again and enjoy it all the same. ZEUS: careful do not touch our bot…

-Ryan

Steve's Individual Reflection

ME 250 made for a very interesting semester. Even though it started out slowly with designing and CAD labs, it quickly became very intense once team design and manufacturing started. Even though I feel I learned much more outside of lecture than in lecture, the lectures were very important to make sure you understood the basic concepts. If you didn’t, it made for a very challenging time in the shop. For instance, because our machine had multiple moving parts that had to fit together perfectly, if we didn’t understand tolerances, our machine could not have worked at all. All of the lecture topics came into play in the design process of our machine, Linkages, belts, gears, racks and pinions, power screws, couplings. If we hadn’t covered these topics in lecture, our machine probably would have come out much different. I was familiar with the design process from my Engin 100 class and the Baja team but this class through something completely different at us. The design for this class made us think of what concepts were good and bad. It then made us think how they could be defeated and what could we do to stop that. It turned out to be a very difficult process because there is only so many ways that you can play the game of Slotbots. We knew that there were going to be a lot of teams doing the same thing because of the limited number of ways to play. So we tried to design a Slotbot to account for all of these strategies.

Working in teams proved to be very difficult at times. It is impossible to think of everything that could go wrong or new ideas when you are with your team. Sometimes I would just be in the library or doing homework and realize that some part of our design just wouldn’t work or that there is an easier way to do it. Trying to get a hold of everyone to let them know to hear what they think proved difficult. It also proved difficult when you come up with an idea, draw it in CAD while at the same time, someone else was modeling something different in CAD. It would have saved a lot of time if we could have met to discuss every detail but that’s impossible with different schedules. When we did finally decide on a design, it was very difficult getting everyone in the shop to work on the project. I didn’t want to leave anyone out of building so at first we tried to get everyone in the shop at a time. This proved to difficult so we worked mostly in groups of two or three at a time. Again coming up with ideas as you are machining proved difficult to get approval from the rest of the team but you just had to work on instinct. Working in teams was a great time though, I had a great time with my team in the shop and in the CAD labs and the LATE nights we spent working at the end. It is always good to have someone there to help you make something you might not be comfortable making or getting approval of a design that could work better.

Time management started out great. We had a schedule and said we would stick to it no matter what. Well that didn’t last very long. We were soon behind schedule and im still not sure when that happened. Time in the shop just seemed to go by faster than we could manufacture anything and soon we were way behind. It also didn’t help that machines were so hard to come by. There were a lot of times we were stuck doing nothing because we could not get on a mill or a lathe. Towards the end we had all our parts manufactured but still had the long and tedious task of assembly. This proved very time consuming and we spent 5 very long days/nights/mornings trying to work out all the numerous little snags along the way. It all ended up working in the end and we finished on time. It would have been nice to have a few extra days to work but our machine turned out AWESOME.

Overall this was by far my favorite class so far at U of M. I had a lot of fun making the Slotbot and although I am upset our machine didn’t work as well as we hoped due to crappy plastic bevel gears. I am extremely proud of what we built. The only thing I would change about the class is possibly open the shop a few days earlier and make more machines available to use. I also think that the GSI’s should build a Slotbot to compete. This way I could see what an older more experienced graduate student would have built. I feel that would have been a great learning aid.

-Steve

Final Team Post

Alright, the final team post.  I guess we have to admit that we hoped to make a deeper run at the competition, but we ran into the winning bot in the quarterfinals and we have to give them props.  On the bright side though, we  did win best mechanical design so our day wasn't totally ruined...  Overall the competition was a smashing success.  Zeus had a few minor glitches initially but our bot preformed well enough to beat a few teams.

On the subject of our bot! First we will touch on our top bot.  Our top bot was one of the fastest bots in the competition.  The sandpaper wheels made it a simple task to climb over any object or push balls around.  The plow mounted on the front of our bot allowed for quick pushing of balls and a prefect front to ram (a purely defensive maneuverer) other bots.  The swivel wheels allowed the bot to turn 360 degrees on the spot.  Overall, the top bot preformed better than initially expected.

Now to the main bot.  This is our slot bases bot, and the meat and potatoes of our design.  The front linkage system pushes open the slot with screw drive, slowly and powerfully.  Next the rack and pinion controlled by the six speed motor turns on, and lowers the conveyor belt.  Once the conveyor belt is lowered, a limit switch is turned on the conveyor belt starts turning.  The conveyor belt is powered by a planetary gear box and an additional six volt power supply.


That concludes our slot-bot competition, now we can sleep again   : ]
Thanks from,
ryan, trevor, colin, steve

Video!

The bot!

Alright, a quick update for all of our devoted followers. We have completed all the components, and are currently fine tuning them and conducting testing in the arena.  The following pictures show our progress!

This is our top-bot, the just after its assembly

Another view of the top-bot, further testing showed we
needed to adjust the wheels and plow.

All the major components are mounted to the frame, with
exception of the conveyor.  We completed wiring over the
weekend

This is our limit switch, it once the conveyor system is
dropped, the conveyor belt motor turns on (switch closes
the circuit)

The six speed motor mounted, and
attached to the rack and pinion

These are our conveyor fame pieces, the preliminary lay-up
for the belt is also shown

Here is how we will be powering the conveyor belt, the motor
 output will be constrained by a brace and bushing

A overview of all the components

The finalized top bot.  The wheels have sandpaper and the
plow has a rod mounted to prevent balls from sticking 

The slot-bot and all its relative components

This is our new conveyor belt system!  

A quick peek at the driving force behind our conveyor belt