I. Scope of project
The scope of my project was to design and construct a frame for a Remotely Operated Vehicle (ROV) for the Marine Advanced Technology Education (MATES) competition. I worked on the ROV with two teammates; Eric Winters and Jeremy Kuhn. My part of the project was to design and construct the frame. The purpose of this frame was to contain the other systems that the ROV would need to operate. The first of these systems, the mechanical arm; used to pick up the PVC caps that represented crabs, on the bottom of the pool during the MATES competition. The second system, the propulsion system; was used to propel the craft through the water in all directions. Finally, the frame held the video camera used to navigate underwater, and the thermometer to take the temperature of a thermal vent. The frame’s purpose was to hold all of these systems together and use all of the systems to make one craft that operated smoothly together.
II. My solution
In September when the teams were finalized, our team; Jeremy, Eric, and I; divided our roles into three parts. My role on the team as mention in “I,” was to design and build the frame ROV. This was the role on the team that I had hoped for because I had researched this for the majority of the summer prior to this course. I had spent most of my time researching different materials to use for the frame and looking online at other ROVs to get ideas for how I would build my frame. During the summer I came up with several rough plans. These three ideas were modified somewhat and drawn in AUTO-CAD as my alternative solutions. Two of these were discarded after my team and I met and discussed how our systems could work and fit together to make one smoothly operating craft. The chosen solution was frame built out of 2” PVC piping using PVC joints at the corners. The frame (Figure 1) was rectangular two dimensional aside from the six protruding PVC caps around the bottom of the craft. These were included in the plan for the frame for adding weight to frame to get it closer to neutral buoyancy after all of the systems were added. The frame was perfect for attaching the arm to the front piece of PVC. The final design of the frame that was chosen has a mesh structure inside of its PVC structure. This frame was perfect for zip-tying the bilge pumps from the propulsion system. The frame was able to hold the camera for navigation as well. This was mounted on the front of the craft so that it could be used for navigation and use of the mechanical arm. I believe that the final solution that was used for the frame was the best possible choice based on the alternate solutions, the other systems that would have to be fitted to the frame, and input from my team teachers and mentor.
III. Discrepancies between design and solution
While building the frame of the craft only one problem stunted the production. The designed frame was too large and looked disproportional when it was dry fitted before it was finally glued together. The frame was overly long and too thin. Not only did it look wrong, but we anticipated that it would not be stable in the water if it was excessively long. Therefore our team decided that the length of the frame would have to be trimmed down. We fixed this simply by trimming off one inch on each piece of PVC piping. This cut the craft’s length from thirty inches, to twenty-eight inches (Figure 1 below). After this was completed the pieces were then dry fitted again and the proportion of length to width seemed better in our opinions than it had been before. The craft was then glued together permanently.
IV. Successes and Failures Successes and failures you encountered during all phases of the project
There were few failures throughout the year and production of the frame. Some failures were not quite failures, but were more setbacks that delayed continuing on with the next step of the project. The first of the setbacks occurred when the bilge pumps were delayed in being shipped. This led to a shorter amount of time after the craft was fully assembled to test it and tweak it to perfection. However, the craft was completed before the competition and there was time to work on perfecting the craft. The second issue was a failure but it was a failure in the arm’s hydraulic system. The syringe on the user side of the hydraulic system broke during the competition, rendering it useless.
The construction and production of the frame as a whole was a success. The drawing of the frame went according to plan. The building of the frame went well too. Towards the end of the year the frame was constructed. This was one of the most successful areas of the project. From start to finish, in the construction of the frame it took less than two weeks. This allowed for extra time for the systems of the ROV to be placed on the craft. After all of the systems were mounted on the craft and were fully operational the craft then needed to be brought closer to neutral buoyancy. The craft was extremely positively buoyant. With the 500 gallon per hour bilge pumps pushing the craft there would not be enough force to sink the craft. The craft was weighed down with concrete in the four corners where the PVC caps were on the bottom. This brought the craft very close to neutral buoyancy. After this was done, the craft was finely tuned with lead sinkers of varying weight to allow the craft to be perfectly stable as it sat in the water. These weights did bring the craft to a state in which it was slightly positively buoyant and perfectly stable in the water. This allowed the craft to easily move vertically in the pool even with a PVC crab in its mechanical arm. Finally, the frame was successful due to its specifications because it was able to hold all of the systems needed to make it a craft and operate according to the tasks set forth by the MATES competition. Overall the frame of the craft was a success.
V. What failures taught me
The few failures that I encountered throughout the project taught me one very important thing. This was to work with those around me and ask for help. Working with my teammates was the key to my successes and the overcoming of my failures. I did not have any failures that related to the frame specifically. It held up perfectly and held all the systems as needed.
VI. Additional learning
After working on this project I learned several new things. The first of these was a deeper knowledge in the area of electronics and how switches and joysticks work. I learned how hardwiring an electrical circuit works and would now be able to create a similar controller myself if need be. I learned how underwater jet propulsion works. I was unaware that water jets do not work if they are sucking in water and the nozzle is out of water. In order for the jet to work it must be in the medium that it is sucking from and force it out in another direction.
VII. Design flaws/ suggestions for improvement
There is one design in flaw in the ROV craft that relates to the frame. This flaw is the size and weight of the craft. The craft completed the tasks that it needed to; the problem however was the speed in which the craft did this. The craft moved much too slowly. This was due not to the size of the craft but the weight of the craft. There are two possible solutions to this issue that could be used to improve the craft. The first of these viable solutions would involve replacing the existing 500 gallon per hour bilge pumps with much more powerful pumps. These pumps could be 1,000 gallon per hour pumps or 1,500 gallon per hour pumps which would drastically improve the crafts velocity underwater. The second solution would be to rebuild the frame of the craft much smaller. This would be more difficult to do after the construction began because the other systems for the ROV were built to the size specifications that were constructed. If the project were to be redone completely, then designing the same frame exactly the same but smaller would allow the craft to maneuver more easily with the reduction in weight to sink it.
VIII. How this project helped you improve my:
A. Problem solving skills
Working on this project drastically improved my problem solving skills. This project forced me to work with a team of two other seniors. By doing this I was able to consult them for ideas when something went wrong. If I found a problem that they could not help me with than I had to fix the problem myself. I at several points of the project needed to fix something on my own. First of all, I would figure out the issue. Next, I would decide what needed to be done to make it right. After that, I would create a method or two that would get me to the solution. Next, I would carry out a chosen plan and fix the problem that was at hand. Finally, I would test the part of the craft or object that I had fixed to make sure that my solution worked with out interrupting the rest of the project. If it did not work than I began this process again. If my solution worked than I would
B. Communication skills through drawing, speaking and writing
My communication skills were greatly improved throughout the year in all of these categories. I did not draw for my project but I became much more experienced in the AUTO-CAD with using 3D shapes. I became much more skilled in technical writing because of all the papers involved in the design and construction process. Finally, the most important skill that I improved this year was speaking in front of people and presenting something that I designed and worked on. At the beginning of the year I dreaded presenting in front of people and was uncomfortable with presenting ideas and objects that I had created. I doubted ever being able to do this easily. By the end of the year however, I feel that I am much more comfortable speaking. I now pause less when I am speaking in front of people and I do not fidget either.
C. Organizational skills
I believe entering this year that I was an organized person. This course improved my organizational skills. For this year I kept all my paperwork in a folder in my backpack. I also kept all of my digital files on a flash drive which allowed for quick access to files when need be.
As the ROV project has been completed and tested, I have felt several feelings involving the project. I feel that the project helped me learn new things involving the technical process in designing and constructing a project. It has helped me work with two teammates who I have grown closer to. I believe that my part of the project was successful and that we were successful as a whole. I am glad that I participated in the ROV project and would do it again if I had to choose another senior project and do it all over again.