When Antoinette Villalpando and Katelin Ashby tossed their robot into the University of Massachusetts Dartmouth pool, the pair’s biggest priority was making sure the machine’s cable did not get tangled and ruin their performance.

There was no room for error at the 2018 SeaPerch Challenge, held at the university from June 1 to June 3, as the team from New Mexico’s Onate High School had the issue in prior competitions.

This time around, Villapando noted she faced depth issues, but they were quick to overcome.

“The pool looks lower than it is because it gets deeper,” Villapando said.

They were two of 172 students from nearly every state in the country, and as far away as Australia, participating in the event. Open to middle and high schools which placed high enough in regional competitions, SeaPerch challenges students to build an underwater robot to participate in two types of events in pools across the country -- an obstacle course, and a challenge.

This year’s challenge involved completing certain objectives underwater, while the obstacle course involved navigating robots through hoops mounted at the bottom of the pool.

For some teams, issues arose during the competition. Hezekiah Karr, from Reeths-Puffer in Muskegon, Michigan, said the team’s robot broke down during the first competition. His quick-thinking teammates were able to fix it in time, however.

“I think we did quite well,” he said, noting this is the first time the team made it to the international competition since forming three years ago.

For its second year being held at UMass Dartmouth, SeaPerch officials decided to expand programming. While the main robotics component was held in the university’s athletic center, the fields and hallways elsewhere were filled with science, technology, engineering, and mathematics activities and challenges as part of a STEM Expo component.

On Friday, each team was given a separate STEM-based challenge -- from building a catapult to a wind turbine -- and had until Sunday to come up with a working design for judging.

“Part of the advancing the STEM Expo was having a celebration of all things STEM,” said Krista Gauthier, the program director of Robonation, which organized the event.