On Saturday June 21, 2009 six UMaine mechanical engineering seniors set out from Orono to attend the 10th International Submarine Race, which was held from June 22 to June 26, 2009 at the Naval Surface Warfare Center, Carderock Division, David Taylor Model Basin in Bethesda, Maryland. The competition is held every other year at the David Taylor Model Basin, a 3000-foot long test tank used for evaluating and testing military ship hull designs and other hydrodynamic testing. This is the largest facility of its kind in the western hemisphere.
UMaine has been preparing for this competition since 2002. Only once before has UMaine attended the competition, and that was the sister competition held in southern California in 2006. At that point the team was only able to achieve a single timed run. The submarines are wet, meaning the operator uses scuba gear when inside the submarine. The vehicles are pedaled or otherwise moved by the muscles of the operator. The complexity of building the machine is compounded by the challenges associated with control, reliability of submerged equipment and the need for efficient use of the limited power available from the operator.
During the 2008-09 academic year three capstone design teams worked on an entirely new submarine for the competition. Convinced that the asymmetry of the previous hull had made complex control problems worse, a new hull was needed. The team set out to make a perfectly symmetric hull for used in the 2009 competition. This was the largest team ever associated with the UMaine machine with 14 seniors participating in the project. As is typical of student projects however, the six-team members who could get away from jobs and family for the June competition took a submarine, names Lobstar1, that had limited testing and which ended up having some predictable flaws. This was, however, the best chance UMaine had ever had for a good performance.
The UMaine team, from the beginning has been committed to the use of a non-propeller driven submarine. The oscillating hydrofoils used on the sub are from a Hobie designed kayak and have the potential to produce at nearly as much power as a propeller for the same application while requiring the engineering design expertise which is critical to the UMaine design experience.
The competition started with extensive safety reviews and both wet and dry safety inspections. But as the week progressed it became evident that UMaine had a machine that far exceeded the performance of anything that they had built in the past. Out of the all of the runs attempted, all except for one resulted in official times. This is for the team that in the past had only received a single official time. This is not to say that there were not challenges. After an initial dry test the electronic control system was removed from the submarine because of the lack of testing and lack of a full range of motion. The manual controls replaced the electronic controls before the first attempted run. Stability was a constant problem throughout the competition because of the design of the rudder mounting system. The submarine would roll on its side resulting in difficulty steering as well as distracting the operator from the power-producing task at hand. Going into Friday, the last day of the competition however, the UMaine team was in second place behind the dominant team at the competition, Ecole de Technologie Superieure (ETS) from Montreal. This was not to last however, while UMaine was struggling with a severe roll and a lower time in their final run. University of California San Diego had a nearly flawless run of 4.103 knots, beating out UMaine’s 3.936 knots to take second place less than an hour before the end of the competition. The dominant non-propeller machine Omer6 from ETS turned in the best competition time of 4.916 knots. The fastest propeller machine at the competition was Talon 1, from Florida Atlantic University, which passed through the speed trap at 6.298 knots.
This is first and foremost a design competition however and in addition to the race a paper, presentation and 17 other criteria are used to evaluate the submarines. Overall the most innovative machine was the submarine from ETS and other overall awards went to submarines entered from High Schools as well as marine design groups. The highlight of the award ceremonies was the standing ovation for the team from Universidad Simon Bolivar, the Venezuelan entry. The Venezuelan team, finally, after a full week of work, got timed runs in the last hours of the competition. The Venezuelan team was clearly the story of the competition, where a team from a country unfriendly to the US was at a Navy facility receiving a standing ovation for a team showing persistence and a good technical effort. The Venezuelan team represented the opportunities for cooperation in education and research.
The members of the team attending the competition were, Nick Gustafson, Jeremiah Richter, Kevin Hopkins, Sam Levinsky, Scott Prince and Mark Liimakka, all seniors in Mechanical Engineering at UMaine. More information is available at the team web site which was a part of their capstone experience working on the submarine, http://www.umaine.edu/MechEng/Peterson/Classes/Design/2008_9/Projects/HPS/index.html
The team and the sub at the competition
Omer6, The submarine from ETS
The UMaine team prepares for a run
The UMaine team after a run, pushing the sub back along the tow tank
Another photo of the team