Kyle Happy's Individual Reflection

Kyle Happy

ME 250

Professor John Hart

12/14/09

This past semester has been an adventure and an amazing experience. While I now have the gratitude for what was done in the ME 250 class, this wasn’t always the case. I learned a lot about the manufacturing process and about all the little things that can and always do go wrong when the team is fighting a deadline.

During this class I learned many things about the manufacturing process. The lecture was able to cover many different manufacturing ideas and concepts very quickly. While I may not have learned everything about the topics covered it gave me a good idea of what to look for while trying to design our final machine. Also I realized from this class the need to go over all the details of a design project like this before the actual manufacturing begins.

The teamwork aspect of this class reinforced the things which I already knew about working in a team. I tried to contribute to the team as much as possible and be a part of every aspect of the team manufacturing process. I also realized that we as a team need to take up slack from other team members when they need us to, and if you do that for them your team mates will happily do the same for you.

Time management was one of the things which I didn’t expect to give me a problem but it did this semester. While my team and I made the deadlines for all the assignments, it was hard, and we came very close to not making it several times. The reason time management was a problem in this class is not because of failed time management but because of an underestimation of the work which needed to be done on the projects deadlines. Because of this underestimation the project did have assignments and milestones which were rushed more than they should have been and thus the quality of that specific milestone lacked a little bit.

This course was well done but it has several things which I as a student didn’t like. First, the lectures were very dry and boring. While I learned about thinks which became critical in the later process of making the final machine, I didn’t realize how critical it would be at the time it was being taught. Also the actual manufacturing of the machine should have been started sooner then what it was. While my team was able to complete the finished machine in time, the entire process of construction was rushed and we did not have time for much testing. If we had extra time for testing of our machine we may have been able to rethink and reconstruct parts of the machine which didn’t work at first. Another thing which I really didn’t like was the book like test which was given at the end of the lecture section of class. While I realize it is U of M and the expectations are high, I think the expectations should be realistic as well. The test asked for such detail and such long answers that I believe it would almost be impossible to finish the test in the time given, even if the answers were known.

Having said all this, I really am glad to have been a part of this class. It is for the opportunity to participate in classes like this that I chose to come to U of M. The class has some kinks which I hope will be worked out for next semester, but the class was a success and could really become a selling point for why young freshmen should attend U of M engineering.

The Victors Video

Dec. 7th weekly update

On Monday, Milestone 9 is due. The requirements for milestone 9 are that
the whole machine is assembled, all the engineering is complete and the
machine can be demonstrated outside of the arena as a moving and working
entity.

This past week has been all about preparing for the milestone 9, milestone
10 (which is due on Wednesday) and the Design Expo (which is this
Thursday). This week we completed all of the manufacturing for the machine.
For last week’s assignment, we had to have the most critical module
engineering complete, have it assembled, and functioning. Having that
finished at the beginning of this week left us to finish the support box,
the second motor mounting mechanism, and the chute.

First, for the support box, we had to cut the ¼” plywood in to the
appropriate shapes and sizes for the sides and bottom of the box. We also
had to purchase some 3/8” thick plywood since we required more than what
was provided to us in the kit. We then used the laser cutter to cut the
appropriate holes in the bottom and two sides of the box. Once the cuts
were made, the box was assembled using wood screws and wood glue where the
plywood was too thin to screw through.

For the second motor mounting mechanism we had to create some “L”
shaped brackets out of the 1/16” thick steel and then bend them at the
appropriate place. We then drilled holes in the brackets to fit the
bushings into for the axle and also to secure the “L” brackets to the
side of the box. The bushings fit smugly into the holes in the “L”
brackets and the axle fits through the bushings. In between the two
bushings there is an axle that is supporting the gear for the
rack-and-pinion device. This axle is extra long on one side to couple to
the motor using rubber tubing, like Professor Hart suggested to us.

The chute was previously welded so that it was the right length, all we had
to do was ban saw small cuts at the top to create an opening in which the
scoops could pass thorough. We then made a bracket for the chute out of
welding rod and then secured the chute into the box using Velcro (so that
it is easily removable when we have to set up quickly).

Next week we will begin testing of our machine. On Wednesday the machine is
due in its final form so we only have until Wednesday to make any small
adjustments that we think need to be made. Also due on Wednesday is the
video for our machine’s introduction. Then on Thursday is the design
expo. After that, the only thing left to do is the individual evaluation of
the course which needs to be posted to this blog.

Nov 30th weekly update

This past week was a short week due to Thanksgiving break however, we
accomplished much. On Monday and Tuesday this week we finished the
manufacturing and assembly for our most critical module. The manufacturing
included drilling holes in the side braces for the axles, cutting the belt
to the needed length and fastening the two ends together, cutting the motor
mount and attaching it to the side braces, and attaching the scoops to the
belt. The two ends of the belt are fastened together using staples, a
simple method that appears to be holding well enough for the purposes of
this project. The motor mount was made out of 1/16” thick steel and was
cut using the ban saw and then bent to a 90 degree angle using the metal
bender. The scoops are attached to the belt using epoxy and electrical
tape, another simple method that appears to be holding extremely well.

One of the important tasks that we accomplished this past week was the
mounting and coupling of the motor. The planetary gear box motor is mounted
near the top axle of the conveyor belt and is coupled to the axle using
3/8”OD and 1/4"ID plastic tubing. One of the problems we are encountering
with our motor is that one of the planetary gears inside the gear box is
too small. We will have to replace the gear in order to prevent jamming
during the competition.

For both aesthetics and the regulations of the competition, we wrapped both
of the side brackets with black electrical tape. The tape helps distinguish
the metal of the brackets from the other metal of the conveyor belt as well
as keeps the conveyor belt from scratching the inside of the slot on the
arena. Since a scratch on the arena leads to an immediate disqualification,
this was a very important step to take.

On Wednesday, we demonstrated our most critical module to our GSI. We
showed our module and its movement in the arena and consequently we feel
the presentation went very well.

Also this week we cut the wood for the conveyor’s support box. The rough
shapes of the bottom, sides, front and back of the box are all cut out and
are ready for further manufacturing. Since we need to make a few small,
exact cuts on both the bottom and front of the box, we have held off on
assembling the box until we have access to the laser cutter to make these
cuts. Once the cuts are made with the laser cutter, the box can be
assembled (we will use wood glue to assemble most of the box and some small
nails where appropriate).

This week we will try to finish all of our manufacturing. We have yet to
laser cut and assemble the support box, cut the sides of the chute, and
couple the second motor to the conveyor belt and attach it to the inside of
the support box. After the final machine is assembled, testing can begin.
We plan to test the machine as much as possible so we will know when small
adjustments need to be made. Also, like we said in last week’s blog, we
will need to continue to take photographs and videos of our progress to
include in the one minute long introduction video that will be played at
the competition.

Nov 22nd weekly update

This past week we focused on the manufacturing of three parts for our most
critical module for the Mile Stone 7 assignment that was due this past
Friday. The three parts that we manufactured were the pulleys for our
conveyor belt, the side bars/braces for the conveyor belt, and the axle for
the conveyor belt.

To manufacture the pulleys, multiple processes were used. Last week we
decided that we wanted to manufacture our own pulleys rather than spending
$60 on pulleys we had found on the McMaster-Carr website. To accomplish
this we used the water jet to cut two circles of 1/16" aluminum and then
used sand paper to sand down the sides of the polypropylene wheels that
were provided in the kit. Then using a drill, a center punch, a center
drill, a step drill and a size I drill bit, we were able to make the holes
for the axle in the 1/16" aluminum circles. These parts put together on the
axle make a pulley that can be used in our most critical module design.

To manufacture the side bars/braces, we used the 1/4" aluminum plate that
was provided in the kit. We used the ban saw to cut this plate into four
equal width braces. These will be welded together to make two 2ft long
braces to support the conveyor belt.

The last part to manufacture was the axle. For this part we used the 3/8"
aluminum rod that was provided in the kit. The aluminum rod was lathed down
to the appropriate diameter and length.

Another part that we made last week for our most critical module was the
scoops that will attach to the conveyor belt and pick up the ping pong
balls. To manufacture the scoops we cut on the water jet 6 strips of
aluminum (1/16" thick). These 6 strips were bent slowly, using the metal
bender in the machine shop, into a curved shape. Unfortunately, due to the
nature of the metal bender, each scoop could not be made into a perfectly
curved shape, nor could each scoop be made the same. This irregularity will
simply allow for some scoops to work better than others, and if we have
time during the testing period, if we find one particular scoop is working
much better than the others, we can alter them the best we can.

One of our other accomplishments this past week was ordering the belt for
the conveyor. We ordered 5 feet of belt, knowing that we will only need
about 4 feet, and we will have to cut the belt to size and then fasten the
ends together, most likely using the Kevlar string that is provided in the
kit.

Since we have to demonstrate our working most critical module this
Wednesday, there is much we still have to finish. We have to cut the holes
for the axles in the side braces of the conveyor belt, attach the motor
mount to the side of one of the support braces, connect the two ends of the
belt, put the belt on the pulleys, and then attach the scoops to the belt.

The last thing we should also begin working on this week is our 1 minute
film that has to be shown during the competition. We plan on bringing a
video camera to the shop so we can get some video of us working on
constructing the most critical module.

Nov 15th. weekly update

The main focus for this past week was to finish the motor lab
assignment. One of the main things we noticed while completing our motor
lab is that one of the sun gears in our planetary gear box set does not
rotate well with the other gears (meaning, that it gets stuck very easily).
If we were to use the 400:1 gear ratio in our module, we would have to
trade one of our planetary gear sets with another team who would be using
the 25:1 gear ratio for their machine. Since we will be needing two motors
for our design (one to rotate the conveyor belt, one to move the conveyor
belt up and down) we will be needing the dual gear box motors as well (most
likely only one of them). In preparation for needing the dual gear box
motors and gear boxes we exchanged the motors that came with the gear boxes
with the ones the GSI's were providing for us during section.
This last week, we also decided on some small changes to our design.
During our most critical module discussion with our GSI, we discussed the
possibility of manufacturing our own pulley for the conveyor belt rather
than purchasing them from the McMaster-Carr website, since the ones we were
looking into buying cost $32 apiece. We have since decided that we will be
manufacturing our own pulleys since we do not wish to spend so much money
on this project, we would rather use the materials that have already been
provided.
During one of our team meetings, we also set a time line for this
upcoming weeks manufacturing processes. During Monday's section time, we
plan to make the path file for the water jet to cut our 1/16" thick
aluminum plate into the appropriate parts we will be needing. Wednesday is
when we plan on doing most of our manufacturing, as well as the water jet
(we are signed up for a time slot on Wednesday to use the water jet).

Nov 8th. weekly update

This past week we presented our most critical module. We compiled the bill
of materials, the manufacturing plan, as well as the engineering drawings
we will need to show the shop before we can begin manufacturing. We also
made some modifications to our CAD solid model, due to some suggestions at
the Design Review.

During our meeting with our GSI one of the main things we discussed was the
tolerances we had indicated on our engineering drawings (on the order of
0.001). The instructor suggested that although tolerances that small are
definitely possible, she does not believe they need to be so small for our
purposes.

This week, we will begin the manufacturing on 3 parts for our next
milestone assignment. The manufacturing of these 3 parts must include the
use of 3 different manufacturing processes and 2 different materials. We
are uncertain which 3 pieces we will choose to manufacture yet because of
the assignment restrictions (2 materials etc), we will most likely not
follow the steps of our manufacturing plan.