Meet the Team:

TEAM BARRACUDA!!!

Week 3: Finishing Parts & Assembly

This week we have been very busy trying to get everything ready for MS9. We spent everyday in the machine shop trying to finish up all our parts and start assembling. Earlier in the week we used the water jet to finish making the side pieces of our robot and worked hard to finish the arm of our robot. Later in the week we focused on our driving unit and started to make sure everything was able to be assembled. Our goals for the upcoming week is to have our machine fully assembled by the due date for MS9 and hopefully have everything fully functioning so we can start practicing. We hope to assemble fast, because we know there will always be an unforeseen obstacles and we want to leave room for that.
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This week was our first time using the lathe and we had several tasks we needed to complete on it. We had to use the lathe for cutting our axels for our rear wheel drive, cut the pin that for our spring loaded arm, bore holes in some of the axels and pin, and also face off all the axels. Using the lathe was new to us, but we didn't have any major challenges while doing it. We were able to get everything done we needed to except drilling the hole in the pin, because we need to ask Bob or Mark for advice how to approach doing that, because it seems pretty tricky especially with the pin being so small.
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Besides for using the lathe, we also used the mill, drill press, sheet cutter, press fitter, and sheet bender. We were focusing on getting the final parts machined, so we could assemble our robot. What we still had left to make were the brackets for the axels, extra brackets to hold sides together, drilling holes in some of our side pieces, and press fitting our bearings into the wheels and axels. We got everything done except for 2 brackets, needed for the axels, and drilling the holes in 6 of the brackets. We should easily be able to drill the holes in the brackets because we have already made a lot and are well experienced with the machine the only problem we may run into is that we have to ream the holes for the axel brackets and we haven't used the reamer yet, however we are confident we can figure it out.  Some challenges we faced this week occurred during  assembly. We found out a lot of our brackets didn't line up with holes, so we had to cut the holes in our sheet metal larger to account for the misalignment of holes. Once we corrected some of these minor mishaps we were able to get our robot 50% assembled. All in all, we had a good week and are hoping to finish our robot by next wednesday except for some minor details.

Week 3: Water Jet and Machine Shop

Today our team split up into two groups to make sure we completed as many tasks as possible in two hours since our deadline is getting closer. Our goals for today were to water jet our robots body, mill our remaining pieces, and drill press clearance holes in the sheet metal. Thursday we hope to start assembling our robot and figure out the placement of the axles and double gearbox. We hope to finish assembling by the end of the week.

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In the machine shop, we had several tasks we needed to get done today. Our main focus though was our MCM. What we had left to complete for our MCM was milling the L-brackets that will hit the balls off the perches, milling the ramp to guide the balls down to the bed of our robot, and band saw the pin for the spring loaded arm. After we finished our MCM parts we focused on getting the rest of the manufacturing complete, so we could start assembling Thursday. The manufacturing left was drill pressing clearance holes in the sheet metal pieces, finish milling and drilling holes in the brackets, and cutting the axles with the band saw. We did a good job today in the machine shop, because we finished the tasks needed in order to start assembling.

We also traded in the spring we had for a spring attached to a guiding pin.  This spring is ideal for us because it can compress more than a regular spring and meets our spring constant needs as well as the extension length we need. We also got the bushings we needed to press fit our axles into our wheels.  The next time we are in the machine shop we will be able to start assembling our driving unit.
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In the Michigan Solar Car machine shop we used the water jet cutter to finish cutting some tricky pieces needed for our body. Before going to the shop today we had to convert our Solidworks files to dxf files. Then when we arrived in the shop we had to upload our files and create a traversing path for the cutter to follow. We ran into some difficulties with the traversing path however. Our main problem was with our right side piece, because our design was curved and some shapes were to skinny. Since the design was curved we had to reconnect all the broken lines so that it would recognized we wanted to cut material out. We then had to make our shapes fatter so the tool size was able

to cut, because our shapes were skinnier then the tool size, the tool couldn't fit in the small shapes and cut the piece accurately. We solved this problem by editing our Solidworks files and making the shapes thicker. By doing this, we fixed our traversing problem and our piece was then able to be cut. Once we got our files all ready for the water jet we were able to cut all our pieces. The benefits of using the water jet were being able to cut out all our pieces with the holes already placed. This saved us a lot of time, since we could use one machine instead of three (band saw, mill, and drill press).

Week 2: Continuing Machining

This week we started to machine the rest of our body and most critical module.  We spent a cumulative amount of approximately 10 hours in the ME machine shop this week.  We mostly worked on cutting the sheet metal for our body as well as cutting, milling, and drilling our brackets in order to assemble our robot.  The parts we accomplished were all the cutting and milling for our most critical module, cutting all the pieces for the body that were to be cut in the ME shop, and starting to work on the brackets for assembly.

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Bracket: machined with band saw,
mill, drill press, and tap.


                  Bottom Bar: machined with
                  band saw, mill, and welded.

                  Used slot cutter on mill in

                  order to get slot on both sides

              of bar.                             _________________________________________________________________________________

Our goals for next week are to finish all the pieces for the body.  This will include going to use the water jet on Tuesday from 8:30 to 10:30am. The pieces we will cut include the sides of our body, the base, and one of the upper bed pieces.  The reason we chose to do these on the water jet was because the base and upper bed piece have cut outs in the center of the pieces that will come out more accurately and easily on the water jet. We are also cutting the side pieces on the water jet because of the hard angles and hole placements that we have for these parts.
Our other main goal for next week is to completely finish our most critical module by wednesday for MS8 and finish drilling and milling all of our brackets.  We would like to start assembling our robot on Friday.

We have made a lot of progress this week and hope to keep up this pace for the rest of the semester.  Our ideal schedule would be to finish everything in the machine shop this week and use the following two weeks to work on assembling our body, most critical module, and attachment of the gear boxes and wheels. We would also like to finish early enough to practice on the table and work out any unforeseen issues we may have.

Week 1: Starting to Machine

     Today we worked in the ME 250 classroom and also in the ME 250 machine shop. Our goals for the day was to build our double gearbox, check all our measurements, and start machining our most critical module (MCM), which is the arm of our robot. We decided to work on the double gearbox and measurements in the ME 250 classroom right after Lecture and other tasks needed to be completed. From 4:00- 6:00 p.m. we are planning on going to the machine shop and work on the mill, drill press, and band saw. We hope to finish our most critical module by the end of the day next Thursday (3/22). Besides from these tasks we also traded some of our materials in, because we needed more sheets of aluminum for our robot. We now have all the materials we need besides a part we have to order. We traded in our Acrylic plate and Delrin plate in order to get 2 more Aluminum plates, 1/16'' thick. We also were able to get a L shaped corner piece, which we will attach to our arm to knock balls off the perches of the tower.

Acrylic and Delrin Plates

Aluminum plates and L shaped
aluminum corner piece

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In the ME 250 classroom we built our double gearbox and also
checked the ball tower measurements. Some of the struggles
we faced when building the double gearbox was that it seemed
one of the holes was stripped of its threads so we were unable
to get the screw to fasten into the hole. Therefore, we had to get
a replacement part from another double gearbox kit, so we could assemble all the pieces and make sure they were tightly fixed together. We also checked our measurements to make sure our MCM was the right dimensions, because we wanted to start machining later today and we didn't want to make any mistakes especially when we are just starting the project.

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      In the machine shop we plan to work on our most critical module (MCM) of our robot. Our MCM for our robot is the arm, which will be used to knock balls off the perches of the tower. How the arm will work is that we will use the L shaped brackets to knock balls off the perches which will then roll down the ramp and land in the bed of the robot. We also have ramps on the base of our robot to ensure the balls make it to the bed of the robot. We have changed our MCM concept from before by making it spring loaded with a pin. How this concept will work is that we want to have the upper bar slide into the lower bar and will be compressing a spring. There will then be a pin placed through the lower and upper bar holding the upper arm down keeping the spring compressed. Our planetary gearbox motor will pull out the pin, which will release the spring and raise the upper arm. When the arm has been raised to the proper place a second pin will stop the arm and lock the arm into place.
    What parts we decided to machine today were the lower and upper bars of the arm and the L shaped brackets. The machines we have to use to manufacture these parts are the mill, band saw, and drill press. Some special features we have to make on these parts are a slot for the pin to slide into and a second hole for the second pin to stop the upper arm from moving. We will also have to ream the hole for the pin to go into in order to make it more accurate and a nice finish. This will be our first time working in the machine shop on our project, so we are expecting to be having some difficulties, but we hope to learn from our mistakes so we can become more efficient.

Calendar:

https://www.google.com/calendar/embed?src=barracudateam35%40gmail.com&ctz=America/New_York

Strategy & Concept:

Our chosen strategy was to knock the balls off the tower ledges and if time permits collect balls the bottom of the tower. We can accomplish this task by using the F-shaped rod on the robot. This pole allows for the balls to be knocked off of the perches of the tower.  The two parts perpendicular to the main pole will be at the same heights as the balls on the perches, so that when the robot drives by the balls will be knocked off of the tower into a hole in the robot. The robot has a hole in the middle near the front of the tower so that when the ball drops it can fall into this hole and no opponent can steal it. Also, there are barriers and ramps on the robot so if the ball doesn’t drop straight
into the hole, which is unlikely, it can slide down the ramp to the hole. Lastly, our robot design consists of a barrier that holds in the balls that we collect from the ground. The barrier lies in the front of the robot and is used to collect balls on the table by driving up to the balls and having the ball go through the gap. Then once the ball is in the barrier is will be guided by the robot to the goal. When the robot drives to the goal it can either release the balls from the barrier or the balls that lie in the circular hole (used to catch balls on ledges) simply by driving over the goal.

Our solid model for our robot