Sunday, December 12, 2010

Final Design

Our final design consisted of a car on top of the table and two plates fastened in the slot to score there as well. We had a basket on the back of our car that could be raised and lowered so that we could get balls behind our car and drag them. It then had a scoop on the front of the car that could push balls as we went forward. This allowed us to get both balls in front of our car and behind it and drag them over the opposing hole to score. The major issue our car had was getting over the center strip in the middle with the balls on it. 
Our bot in the slot consisted of a linkage made of pbc to score balls and a extending arm with a ratchet on it to push the flipper open. The linkage was powered by a motor that would push balls into the hole. When the linkage began to move it would release a string that was attached to our ratchet and this would release our extendable arm that was powered by two compressed springs. This arm could then not be moved back in because of our ratchet. This allowed us to block the flipper and score with the use of only one motor.


Individual Reflection - Juan G. del Mazo

Saturday, December 11, 2010

Individual Reflection- Court Murtland

This class has definitely taught me more about engineering than any other class simply because of the amount I learned about the design and manufacturing process. Before this class I had never had hands on experience in the workshop or even began to design something that would be built. This class taught me how important every detail is and what a long, detailed process building something is. I learned that any over looked detail in the design and brainstorming process, no matter how small it may seem, can become a major problem when it comes to actually making that part. Another thing that surprised me was how parts that seemed so easy to manufacture on solidworks could suddenly become unrealistic and changes would have to be made to our design to accommodate for this. Overall, I learned what design and manufacturing is like outside of the classroom and in the real world. In this class we got to take all the knowledge we learned in lecture and discussion and apply it to our slot bots design and manufacturing.

This class required more time and work than any other class I have taken at this University. Although it could be extremely frustrating at times, I would tell any student who takes this course in the future to stick with it and put in as much effort as possible, because the knowledge you learn from this class is invaluable. Due to this amount of time this class required, time management and teamwork were extremely important skills. I would definitely tell any student taking this class to try to put in as much time as possible to the design process because it will safe you a lot of headaches down the road. Also, try to get in a group that has a similar schedule as you because you will need to meet almost every day for weeks. I learned how to play to each team members strength in this class because you will need to use your time wisely; you must learn how to do everything but if possible everyone should have their personal responsibilities since everyone has different strengths and weaknesses. i learned a lot from the left vs right side brained people lecture and our group used this information to give out specific group roles. Before this class I had never used solidworks before and had very little experience with any type of CAD software but in the beginning of this class I learned how to design my own individual parts for the first few individual assignments. By the end of the class our group had designed a car, an extendable arm with a ratchet, and a linkage. The most important thing that I learned however was how to use the machines in the shop to build our slot bots. I had never worked with my hands before on a project like this and had no idea what I was doing at first but now I can work the lathe, mill, drill press and other tools without thinking about it. We spent countless hours in the shop and I honestly feel that this is the most important thing that we learned in this class.

One improvement that I would suggest for this class would be to make groups earlier in the semester and push all the deadlines forward to give the students more time to manufacture and test their bots on the table early enough to make more adjustments. The first month of the semester the work load for this class was extremely little compared to the last month and if you could give students more time to test their bots with all the balls on the arena during discussion would make each teams slot bots to work better. I know that we would have liked to buy new wheels for our car so that it could go over the middle strip more easily but we simply didn't have enough time to get them and remake our shafts and pillow blocks. Another change you may want to consider is making the rules set and not able to be changed by an earlier date in the semester because I know our group and other groups had to make major changes in our design half way through the semester and in the end I think this hurt the performance of our bot. Overall, I learned an incredible amount from this class and think it will help me more than any other class once I get a job in the engineering field.

Finally, I will discuss the things that could have helped to improve my performance in this course. The thing I wish I could change now is making more in depth conceptual drawings and ideas during the early design process. Another major problem we realized just a few days before the competition is that the slot was not quite as wide as the CAD drawings said it was so we had to make major changes to our bot so that it could fit and in the end this made our linkage no where near as effective as it had been before these changes. I would have measured the slot on each arena before making our bot because this was our biggest problem in the class. Finally, I would plan for more problems in our manufacturing process because I had no idea so many things could go wrong, just like the width of our slot bot that I mentioned before. I would like to thank professor Hart, Davor, Mike Umbriac, Bob and John for all the help, making this class possible and such an excellent learning experience.

Final Document and the Design Expo~!!







Our final project had two modules, one on the top and one on the slot just as we planned. The top car had the ability to push the balls on the middle and grab the ones in the outer edge of the table and take them to our basket. Our other module had the ability to open the flipper and scoop the balls in using a linkage just as planned. A lot of adjustments were made in order for the bot to fit in the slot seeing as the measurements given to us were a bit off. We had reduce the plates width and take out a large amount of metal from the left plate in order to have the linkage fit and move smoothly without hitting the sides. Although we never were able to score the linkage did work on the second round of the competition we were unable to score because the other team opened and blocked the flipper before we were able to. The previous times we weren't able to score because we had problems with our gears the first time and the second time our pulley was loose on the shaft. If we would have made these adjustments we would have given a better performance.

Here is the final bill of material of our project, plz check it out~

Individual Reflection ~claire

While this class was definitely my most stressful class of the semester, i noticed immediately after it ended how much i missed and enjoyed it. I learned a great deal in the course. i enjoyed having hands on project and having the opportunity to design and build a fully functioning machine. in the class i lerned a lot about how important the design process is, especially when we have so many components and modules working together. we have to carefully exam each component carefully and assemble them first in Solidworks. i feel this way because without a good plan then we are basically going to be wasting time in the machine shop. ME250 taught me a lot about some of the most important parts of design and manufacturing including teamwork, time management, and the mechanical components and machines used in a manufacturing based environment.
At the begining of the semester i was a bit intimidated by the amount of team work that this class required. i had never done anything similar to what we did in this class. ME250 was probably the most challenging and time-consuming class this semester. it required a lot of time, dedication and teamwork. but after all, when i finally made a machine by myself, i was so proud of myself and realized how much ive learned from every mistakes. having to manufacture everything was a great learning experience. it gave me a good understanding at how precise manufacturing can actually be. this class has given me much more respect for how difficult manufacturin can be. on the other side, it was very helpful to have the CAD lad and assignments. i feel much better knowing Solidworks because i know that will be integral part of being a mechanical engineer. Also being able to get the Solidworks on our personal computers was extremely benefical so we would not have to spend hours in the library doing CAD.
In terms of course improvement, i felt a lot of times were wasted on FRDPARRCS instead of more meaningful topics and actual manufacturing. it would have been nice to let us work in the lab and learn how to deal with the variety of mechanical components and stuff. for someone like me that have no design experience before, it would be tough to come up with an idea and tun it into reality. we learned about some things in lecture that we never even touched on during lab.Also, it would have been much better to assign the teams sooner in the semester so we could have more time to work on the machine design. another thing we should do in this class is filling an availability form at the begining of the semester and posted it online, so we can refer to each others' schedule to form teams, so that it wont have time conflict on group meetings. The homework assignments in the begining didnt seem to help with the project very much. it would have been nice to have assignments more toward the kind of stuff we should need to know for the project.
To improve my performances, i could have taken more time on some of the homeworks and lectures to fully understand all of them. maybe spend more time during the designing phase and measured everything carefully to make sure there were in interference on the final machine. if this would have been done, then there would have been no way that the machine would not fit or not functional work. overall, despite of the tough period of design and manufacturing, ME250 was one of the awesome class ive ever took. working with lemon lawyers was fun and educational. we all learned something from each other, and i learned that teamwork can be way more successful than individualized work when done properly.

~Yufan(claire) Liao

Monday, December 6, 2010

Building Complete











Last week we completed our car on top of the table as well as finishing the rest of our machine in the slot. We spent approximately 6 hours in one of the two shops all 5 days during the week and then would meet at night to discuss our plans for the next day. This way we did not waste valuable time when we were signed up in the machine shop. Then on Friday night we tested our machine and only through testing each individual part were we able to find out what needed to be fixed by using a calculators batteries as a power source. Saturday and Sunday were spent in the Wilson Center making small adjustments to shafts and the way every shaft was connected or even possibly bent.



On Monday we were able to test our machine on the actual arena and learned that the slot was slightly smaller than 2.5 inches wide due to tolerances so we had to make one of our aluminum plates thinner and change some of our shaft lengths in order for our machine to fit into the slot. Finally, we had to redo our acrylic frame that holds our extending arm because the top was beginning to break so we wanted to eliminate that possibility. This time we will screw each piece of acrylic together since we decided that the glue we were using was not the best option. Our final challenges are to make sure that the linkage will continue to work flawlessly in this new more tightly confined space in the slot and make sure that our car will be able to go over the plastic strip in the center of the arena when it is carrying a lot of balls.









Lemon Lawyers Out