UCSD Human-Powered Sub Competes Internationally

We previously showed you how a team of engineering students from UCSD designed and fabricated a unique human-powered submarine as part of their classroom learning experience. Instead of using a rotary propeller, they took a cue from marine life and designed a dolphin fin propeller.  The students then competed at the European International Submarine Races in Gosport, England back in July. Here is a write-up from Tobin Gutermuth, the team captain, about their experience.

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In Tobin Gutermuth’s own words…

As many of you know UCSD HPS made it to the European International Submarine Races for the first time this year. Myself and six other teammates attended the event held at Qinetiq Ocean Basin in Gosport England from July 3rd- July 14th. We stayed in Kingfisher caravan (trailer) park next to the beach in Gosport with race officials and 11 other teams from around the world.

From 9am to 4pm teams would fix, modify, and race their submarines in the amazing Qinetiq Ocean Basin. The pictures do not do the basin justice. Diving and racing in the perfectly still crystal clear water of the basin was such a unique opportunity which we would not have without the generousity of Qinetiq, and the dedication of the race organizers who volunteer their time to put on this fantastic event. It was really amazing to see the fully flooded submarines start off perfectly still, suspended in the body of water (near a half ton of neutrally buoyant mass), then accelerate off of the start line like a torpedo or in our case like a dolphin. The race course was made up of a straight away with a timing trap, u turn, and back through a slalom course.

At 4pm all teams returned to the trailer park. There we got to know the various teams, sharing meals, drinking cheap beer, and hanging at the beach. IMarEST and the race organizers also held several events including a BBQ the first night, a lecture on Submarine design at the Portsmouth historic dockyards, an open house where the teams presented their designs to the public and to eachother poster board style, a tour of the Royal Navy Submarine Museum where we got to walk through the HMS Alliance, the only remaining WW2 era submarine (a real highlight of the trip), and a talk on deep ocean exploration.

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On the last Friday of competition everyone attended a black tie event at a hotel in downtown Portsmouth with three course dinner and open bar, how the British Royal Navy does it. Before dinner we had an award ceremony. Vaquita got 7th place out of the 12 submarines. The judging was based on Design Report, Dry Inspection (where the quality of our design and build were judged), Wet Check (where each team had to demonstrate their pilot Safety Buoy function and pilot escape underwater), Race Performance, and Reliability. Unfortunately the performance and reliability of our submarine was severely impacted by a poor choice in buoyancy foam. The foam we used compressed at depth in the ocean basin. So, even though we were correctly trimming the submarine at depth, as soon as the depth changed (i.e. the submarine coming closer to the surface), the foam expanded and made the submarine increasingly buoyant, sending our sub up to the surface. We failed to notice this design flaw during testing because we only went a short distance in the school pool and the pilot stayed at a relatively constant depth.

Nonetheless, we still managed to cross the finish line four times, albeit at the surface. All the other systems in the submarine (drivetrain, steering, safety) were functioning normally. While we couldnt see the full potential of our propulsion and steering systems, we were glad to have completed several races at EISR, including navigating the slalom course. While we wish we could have performed better, we know that this project is really about learning and we certainly learned a ton this year.

Vaquita was also awarded with the most unusual design award. Of the 12 submarines there were only three non propellor subs. The other two non propellor subs used Hobie Mirage drive propulsion systems. We received a lot of enthusiasm from the judges and other teams about our unique design.

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The spirit of the races is all about camaraderie, having fun, and learning. Teams shared tools, divers, and tips/experience about how to improve subs, manage teams, and fundraise. We are a small community of human powered sub engineers. I hope that UCSD will attend the European races for many years to come. Next year the team will be lead by 3rd year Xander Westra, the propulsion lead from Vaquita. The team will likely reuse the same hull and focus on building a stronger team mentoring new members by having them improve existing systems. The team plans to attend the submarine races at in Maryland next summer.

Big thanks to all our corporate and school sponsors this year:

UCSD Jacobs School of Engineering
American Society of Naval Engineers, San Diego Section
American Society of Mechanical Engineers, San Diego Section
UCSD Mechanical and Aerospace Eng. Dept.
UCSD Structural Eng. Dept.
Northrop Grumman
SunRez
Oceanaero
Coastal Enterprises
UCSD Structural Engineering Undergraduate Development Labs
UCSD MAE Machine Center
UCSD Visual Arts Department
Triton Engineering Student Counsel
UCSD Drone Lab
Lormac Plastics
Teledyne Seabotix
Aeromarine
UCSD Envision Makerstudio
Revchem Composites
Fiberlay

Coastal Enterprises manufactures Precision Board HDU, a high-density urethane material used extensively in the tooling industry.  It is a closed-cell rigid material that does not rot, warp or crack.

Coastal has a long tradition of donating Precision Board HDU to schools around the country in support of the next generation of engineers, designers and artists working in composites.  If you are interested in finding out more about our Precision Board school donation program, check out our School Donation page and get in touch with us to see how we can help your program out.

You can read part 1 of this blog HERE where they describe the process of using Precision Board HDU to create the molds for the submarine.

UCSD Human-Powered Submarine Mold-Making

A team of engineering students from the University of California – San Diego (UCSD) designed and fabricated a unique human-powered submarine as part of their classroom learning experience.  Instead of using a rotary propeller, they took a cue from marine life and designed a dolphin fin propeller.  The students created fiberglass female molds out of Precision Board HDU which were used to create a carbon fiber hull for their submarine.  In a series of videos, the human-powered submarine team show us how they went from design to fabrication and every step in-between.

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Tobin Gutermuth a structural engineering student and president of UC San Diego’s Human Powered Submarine Team and documented their process from design to fabrication and showed how they used Precision Board HDU to create female molds that would eventually be used to make a carbon fiber hull.  Competing in the one-person non-propellor division, Vaquita features an up-down tail for propulsion, a unique six-bar linkage, and the team’s very first pneumatics systems. The heart of the submarine is its drivetrain, which translates rotational motion into oscillation. The pilot propels the submarine by pedaling the drivetrain, which uses an innovative six-bar linkage to swing the tail up and down.

According to an article on the UCSD website:

The students made several major design and material changes to their sub this year. For starters, they’ve switched from trying to emulate the side-to-side motion of a tuna tail, and instead are mimicking the up-and-down sinusoidal movement of dolphins. The races in Maryland only require contestants to speed in a straight line, whereas the race in England has an obstacle component that the sideways motion wouldn’t be ideal for.

“We came up with a linkage system in the submarine tail to optimize for a perfect sinusoidal force output,” Gutermuth said. “Linkage systems tend to jump, but this one was optimized using a genetic algorithm to optimize for a perfect sweeping motion.”

“We used several 1.5 inch sheets of Precision Board to build 7 blocks of foam,” he says. They then machined the blocks of foam with a Kuka Robot CNC at UCSD to build a plug in seven sections.

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Tobin says, “we bonded the sections together and made a fiberglass female mold from the plug.”  He adds, “we made an awesome carbon fiber hull in two sections using the female mold!”

You can see videos of the entire process below, including their test run in the pool.

The UCSD crew first cut the sheets of Precision Board into smaller size pieces to be able to bond them together.

They then took the smaller pieces and bonded them together into larger blocks using Coastal Enterprises PB Bond 240.

Then the UCSD team used a CNC machine the bonded blocks and assemble them to form their plug.

Finally, they shared with us a compilation video of the build process for Vaquita, their human powered submarine, showing all the mold making processes.

After the submarine was built, it was time to test it out in the pool.

After the submarine was completely built and tested, it was time to compete.  You can find out how they did at the 2018 European International Submarine Races in our follow up post with a report from the UCSD HPV team themselves next week!

The Human Powered Submarine team at the University of California San Diego designs and builds a fast, safe, and reliable fiberglass submarine that competes at international submarine races, which take place in Bethesda, Maryland and Gossport, UK. Scuba-certified students control the submerged and flooded submarine with human powered propulsion. Students working on this project learn essential CAD, machining, and programming skills and gain a deeper understanding of the concepts that they learn in their classes.  The most recent submarine, completed in 2018, is “Vaquita,” named for an endangered species of dolphin. Competing in the one-person non-propellor division, Vaquita featured an up-down tail for propulsion, a unique six-bar linkage, and the team’s very first pneumatics systems.

Coastal Enterprises manufactures Precision Board HDU, a high-density urethane material used extensively in the tooling industry.  It is a closed-cell rigid material that does not rot, warp or crack.

Coastal has a long tradition of donating Precision Board HDU to schools around the country in support of the next generation of engineers, designers and artists working in composites.  If you are interested in finding out more about our Precision Board school donation program, check out our School Donation page and get in touch with us to see how we can help your program out.

UCSD Human Powered Submarine Takes The Plunge

UCSD ASME students took the plunge with their Human Powered Submarine, “Legasea”, at the 12th International Submarine Races in Bethesda, MD, this past June.

The event was held at the Carderock Division of the Naval Surface Warfare Center in the David Taylor Model Basin, one of the largest ship model basins in the world. The competition consisted of 19 teams competing in a 100 meter race. Each team was required to design and build a one or two-person “Wet” submarine, which has a completely flooded hull and requires the crew members to breath SCUBA from an onboard air supply.

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UCSD students designed and created “Legasea”, a 2-man, propellor-driven, Human Powered Submarine that was designed with SolidWorks and built from scratch by UCSD students. Students relied almost entirely on donations, both material and financial, to bring Legasea to life.

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Coastal Enterprises was proud to donate Precision Board to the UCSD Human Powered Submarine team to use for their mold-making process for the submarine’s body.

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According to Elliot LaBarge, team leader, “We planned to use the 10lb and 15lb. Precision Board we had to make molds we could pull the fiberglass body components of the submarine from. Since the submarine is 21′ long, we decided to make three separate molds and join them together – a task we learned was much easier said than done, due to the large size of the molds.”

Diversified Manufacturing of California was kind enough to lend their CNC capabilities and expertise to the students, producing three perfect molds from Precision Board PBLT-10 and PBLT-15 and spraying them with PLC Polyprimer 903 Black. Once the molds were back in the students hands, they coated them with a Honey Wax mold release compound and PVA (polyvinyl alcohol), and were able to successfully pull three separate body components – a fiberglass nose, center and tail.

Once the body components were ready, the battle wasn’t over yet. An extensive assembly process began followed by as much testing as possible before the race.

“Precision Board worked great because not only is it durable and able to withstand several pulls, but it also has excellent machinability, which really helped us bring the submarine we designed to life”, says Elliott.

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When it came time to race in June earlier this year, Legasea placed 3rd in the two-person, propellor-driven category. Sub speed was measured by two timing gates halfway through the course, which recorded Legasea’s top speed at 3.42 knots. Unfortunately, a critical failure of the steering control rods rendered them inoperable, resulting in Legasea being unable to complete the final race.

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The next International Submarine Races will be held in June of 2015, and Coastal Enterprises will be working closely with the new team leader, Mr. Alistair Twombly, as they redesign Legasea for the next competition.

Check out more info about this project on the official UCSD Human Powered Submarine website: http://asme.ucsd.edu.

Video of the final “pool test” prior to the race: