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

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~

https://spreadsheets.google.com/ccc?key=tixA5Mg-yiqLgfkAs5KnqmA&hl=en#

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

Final Presentation

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

Update #4-MCM Complete

Last week we completely MS#8 and our mcm except for the motor connection. We were able to overcome problems with our pulley and belt assembly by using two parallel plates that allow us to adjust the height of the pulley in order to keep the belts tight and rotate our links. This made our linkage much more efficient and less likely to fail. We also expanded our manufacturing plan so that we know exactly what needs to be built and how do build it, in order to complete our slot bot.

This week we will need to completely finish cad design for our top car and discuss and change a few problems that we can for see in manufacturing it. These problems need to be changed early in the week so that we can begin making each part, we have already signed up for every day from 12-2 and plan on signing up at other times as well as meeting today at 2 today to make these changes. Finally, we will need to come up with our final schedule for shop times and completing our entire slot bot. this will allow us to know exactly when each part will be manufactured and our entire bots will be complete allowing a few days before the competition in case any problems are found with our machine during this process.

here is the updated schedule and to-do list:

https://spreadsheets2.google.com/ccc?key=tVwoB8C_F03Y2R0tkkxGLUA&hl=en#gid=0

https://spreadsheets1.google.com/ccc?key=t9FQhkt4mkrfURXTnIMrkmA&hl=en#gid=0

Hope everyone had a safe and happy Thanksgiving.

update #3-second week manufacturing

This week we focused on manufacturing all the linkage components, including shafts and arms. when all the components were done, we press-fitted the busings we bought and tried to assemble components. However, we met a problem that the shaft does not fit into the bushing and also it is too short for placing two washers at the ends. Then we modified the dimensions of our shafts a little bit by reducing the length between the groove and the end faces, and made the shafts again. At the same time, John helped us to reamer the size of the holes and Claire looked for thinner washers. finally, all the pieces came together and worked pretty well. we can rotate each link nicely and smoothly.

This week we also machined the pillow stockes for our top car. Claire used the linear band saw to cut the pieces into right sizes and then drilled the holes on them by using the drill press. Next, Claire used 0.375 in reamer to open up the holes and press fit the bushings into it.

next week, we will still be working on our MCM- linkage, we are planning to assemble the right body plate with the linkage, machine the scoopers, and connect the linkage with motor. hope we can get that done by thanksgiving.

Update #2- First week machining

During the first week in the shop we focused on making the linkage arms and the shafts for our most critical module. Before we start machining, we realized that using Aluminum for the arms is not a good way to go since its relativly heavy and pricy for what we want to make. Then we decided to use PVC for our links and confirmed with Davor that we are able to get some pvc pieces from the shop for free. Hooray~ By having our raw materials ready, we were about to start. We divided our team to two sub-teams. Juan and Jim were working on the links by using milling machine. Claire and Court were woking on the shafts by using lathe.
To start, we cut and faced our pvc block to be 1'' and 1/2'' thick, and sized them to the right dimentions. Then we used mill to drill holes on the link pieces in orde to place shafts. At the end of the week, we basicly finished the links except the holes on the side that need to be put set screws.
At the same time, Claire and Court were machining the shafts. We started by cutting the shafts to the right length. Then we used the groove cut-off tool to make grooves for E-clips. However, we met a problem that the surface around the grooves we cut were not flat. we asked John and he suggested us to use small fier to get rid of the small chips. That helped us a lot and the shafts looked much nicer. next, we used lathe to drill holes in the center of the shaft by using the #27 drill bit. Of course, we started by using the center-point drill bit.
I think we had a more clear idea on how we are gonna machine our parts after the first week. As we experience more in the shop, we will be more familier with the tools. Above are some pics of the things we have done during the first week, please check them out~ ^^

Update #1 - Most Critical Module Drawings

Last Friday we had to hand in drawings for our most critical module.  We agreed that our most critical module was the linkage since without it we can't score on the slot, which is the main goal of our strategy.  After designing it on Solidworks we showed our GSI (Davor Copic) what we had.  He was not pleased at first, and gave us a lot of VERY HELPFUL pointers on how to modify our module to make it more machinable, more feasible and more competitive.  We worked on it for 8-10 hours straight and the next day we showed our GSI the progress for which he said it was an excellent work and he saw improvement in our design.  Here are some of the drawings we made and plan to use for our manufacturing process this upcoming weeks. 

LAWYERED!

-Marshall Eriksen

Lawyered!

Court just got lawyered... Today we went to a place further away from the possible and the impossible, it is where they meet, we call it... THE POSSIMPIBLE!!!!

Calendar for Fall Semester

To view the lemon lawyer's awesome calendar just click here ---> http://goo.gl/nb5k

Strategy and Concept Description

Our strategy is based on playing defense on the top of the table while we play offense in the slot.  From this strategy we developed a concept in which there will be two different modules, one sitting on the table top and another inside the slot.  The defensive module would sit on the table resting inside the slot for stability and would extend arms to disturb the path of any slot-bot trying to score on the table top.  The bottom module will extend an arm to open the flipper, and once it is open it would use a linkage assembly to score the ball in our bin.