WESTH BETHESDA, Md. —
College and high school interns at Naval Surface Warfare Center, Carderock Division raced boats they printed and assembled themselves during the inaugural Naval Sea Systems Command (NAVSEA) Additive Manufacturing (AM) Challenge in West Bethesda, Maryland, July 28.
Intern groups were given one month to design and build a proof-of-concept surface vehicle. Each group was given a standard kit of parts and access to the Manufacturing, Knowledge and Education (MAKE) Lab’s 3-D printers. Once the vehicles were built, participants were challenged to maneuver through an obstacle course in the David Taylor Model Basin, said Michael Britt-Crane, AM Tiger Team member.
“The basic idea is that we have a standardized set of components: motor, battery, electronic speed controller, the RC system and servos. Each group has that same set of components and just about everything else is 3-D printed,” Britt-Crane said.
The NAVSEA AM challenge is testing out concepts the AM Tiger Team has for AM to support the Navy and Marine Corps in a forward-deployed environment.
“The idea in the far future is we’ll have all the electronics on the shelf and have 3-D printers forward deployed. With reference designs on hand, a Sailor would have the capability to 3-D print an unmanned vehicle and deploy it within a very short time frame. Vehicles could even be customized for a specific mission.” Britt-Crane said. “So these guys are kind of testing that concept out. One of our groups built theirs in just a week.”
Students created boats named “Mongoose,” “Porky” and “USS Boaty McBoatface” with a common set of components, but with original designs. The watercraft were printed using 3-D printers in Carderock’s MAKE Lab. Sean Black, who created Mongoose with his teammates Matthew Dapp, Brooke Merryman and Jacob Blumberg, said combining their knowledge was essential to creating a functional vehicle.
“Brooke and I had additive manufacturing experience before this internship; our other teammates didn’t, to my knowledge, but Brooke and I didn’t have naval architecture experience, so we didn’t know where to start or how to go about this,” Black said. “All we know is we have to design a ship and 3-D print it. That part I can do no problem. We started by modeling our design after the first thing we thought of that would be easy and quick to model: a rowboat shape. Michael set us up with teammates who had more knowledge about naval architecture who gave us ideas on how to make the ship turn better, go faster and be more stable.
“We had many failures and we were really pushing the printers to their limits. Trial and error is how we learned. We slowly adjusted our design, printed half-scale models and put them in the water to see if they would float. We went through doing different variations of our print, printing it over and over again until we were happy with it. I feel pretty good about our product. There are some changes we could have made to give us more speed. But I think our shape was decent; for the time we had, it’s a great design. It’s not at the bottom of the basin. That’s what we’re proud of. We definitely learned a lot about naval architecture that we didn’t know before.”
Black said his team competed with the very last print they made of Mongoose, which ended up winning the time trials over USS Boaty McBoatface by less than two seconds. While Porky came in last, Britt-Crane said it’s understandable and still impressive considering that entrant was created the fastest. In the head-to-head competition, all three craft improved their times and USS Boaty McBoatface took first place.
“With all three running, they were bumping fenders and there was a lot of contact, but they all survived and finished the course,” Britt-Crane said.
This summer is Black’s fourth summer at Carderock under the Naval Research Enterprise Internship Program and the Science and Engineering Apprentice Program. He said he has spent a lot of that time working with AM and in the MAKE Lab, where he used the 3-D printers for this challenge, and that he has found working on projects like the AM Challenge rewarding and typical of what he has been able to do at Carderock Division.
“I have spoken to people who have been interns at other places, and some of them are just given busy work to do and their work isn’t very important,” Black said. “Here at Carderock, I know my work is important and I can see it being implemented. And the AM Challenge was a lot of fun; I’m really glad I got to be a part of it. We learned a lot and it was definitely an enjoyable experience.”
Britt-Crane said the AM Tiger Team got the idea for the challenge by leveraging their Cooperative Research and Development Agreement (CRADA) with Virginia Tech, which has done similar AM-centered challenges with air and land vehicles. This first iteration is intended primarily as a pilot/demonstration to learn about the design space and show the work the challenge can produce, but he expects to expand the competition portion in future years to include print time and assembly as judging criteria.