What sinks like a sub, drives like a tank and thrives in a pool?
The ROV! It's a Remote Operated Vehicle created by a group of Clatsop Community College students.
They leave today to take their invention to a national competition at NASA's Johnson Space Center's Neutral Buoyancy Laboratory in Houston. It's the first time the college has participated in a competition this big, and the ROV's creators are optimistic that they'll hold their own against other community colleges, high schools and universities.
"We're probably going to go there, accomplish every task, and possibly win," said Brian Marshall, college Maritime Science student.
The ROV is a small, water-going vehicle comprised of bilge pumps, plastic pipes, propellers and cameras. It's powered by a 12-volt battery, and operated from land by something similar to a remote-controlled car controller. The person who manipulates the ROV looks at TV screens fed by live images instead of at the ROV itself.
In real life, ROVs have a variety of uses. They can be sent down to count fish traveling upstream, examine river bottoms and fish habitat, inspect the bottom of a fishing boat and explore sea vents off the Oregon coast. The Titanic was first discovered and explored by an ROV, and the Mars Rovers, which can take pictures and analyze rocks and soils, are ROVs built for space.
In this competition, the ROVs are designed to accomplish three underwater tasks: shutting a valve, dropping a communication probe in a hole and attaching a plate to a platform. The students will also be graded on how well their vehicle has been engineered and on their technical report. Science students, led by Marshall, designed the ROV, while students in a technical writing class wrote the report.
During a testing session at the Astoria Aquatic Center, Marshall set the ROV in the pool. Electrical cords wrapped in survival suit material (so they would float) connected the ROV to the controls. The unit has weights on the bottom and buoyancy compensation on the top. Finding the right combination of weights and floats was one of the group's more difficult tasks. The first day they put it in the water it turned upside down and sank.
"You should have seen the first couple times, total failures," Marshall said. "It would sink to the bottom, only go one direction."
Now the ROV can change depth, turn in circles and move forward and backward, however it has no lateral movement. Marshall pushed the switches back and forth to demonstrate its dexterity.
"Everybody loves this thing," said physics student Jeff Doughty. "We took it out to Coffenbury Lake. There were some old-time fishermen there who thought it was totally cool."
Doughty was responsible for soldering the direct current motor controller - a project that directly related to his physics class, which was discussing electricity, volts and amps at the time.
During the competition he'll likely be driving the ROV - since he played a lot of video games in his day.
Physics instructor Pat Keefe said building the ROV showed students how frustrating it is to work out the finer details of an engineering project. It's one thing to play around, quite another to make an invention work consistently.
"It was a good opportunity to see how an engineer functions," he said. "They think they want to be an engineer, but really don't know that it means."
Keefe said building something that won't sink or spin in circles is hard enough, let alone operating it blind or with the extreme control it takes to close a valve.
"I would be impressed if they could just bump into the (underwater challenges) and knock them over," he said.