CMU Biorobotics Lab unveils submersible snake-like robot

Carnegie Mellon University has developed a snake-like robot that can work underwater, making it a tool that could prove beneficial for inspecting boats and underwater infrastructure and completing other tasks.

A team from CMU’s School of Computer Science’s Robotics Institute’s Biorobotics Lab tested the Hardened Underwater Modular Robot Snake (HUMRS) last month in the university’s pool. The robot dove through underwater hoops, showcasing its precise and smooth swimming abilities and demonstrating its ease of control.

“My research group has been working on snake robots for quite some time now,” Howie Choset, the Kavcic-Moura Professor of Computer Science, said. “What’s great about these robots is they can get into tight spaces that people and machinery otherwise cannot.”

Choset and Matt Travers, co-directors of the Biorobotics Lab, led the project.

The submersible robot snake was developed through a grant from the Advanced Robotics for Manufacturing (ARM) Institute. The project aims to assist the Department of Defense with tasks like inspecting ships, submarines and underwater infrastructure for damage or routine maintenance, said Matt Fischer, the program manager at the ARM Institute working on the project.

For the military to inspect a ship’s hull, the Navy has to either send a team of divers to the ship, wait until it returns to port to deploy divers or put the ship into dry dock. Those options are all costly and time consuming.

But a submersible robot snake would allow the Navy to inspect ships at sea, alerting the crew immediately in the event of critical damage or sending information to port about issues that may need attention.

“If they can get that information before the ship comes into a home port or a dry dock, that saves weeks or months of time in a maintenance schedule,” said Fischer, who served in the Navy for three years. “And in turn, that saves money.”

The snake-like robot could also prove beneficial outside of the military, too.

The technology could be used to inspect underwater pipes for damage or blockages, assess offshore oil rigs or check the integrity of a tank while it is filled with liquid.

“The applications of these robots include search-and-rescue or even surgery,” Choset said.

Versions of the robotic snakes have already proven to be beneficial in such circumstances. In 2017, a team used robot snakes to assist with a search-and-rescue mission after an earthquake in Mexico City.

The robot’s modular design makes it adaptable and adept at squeezing through tight spaces, climbing and navigating corners.

The robots can be tweaked to fit the needs of unique projects, which, Choset said, gives their robots an edge over other types of snake robots produced by other groups.

“What makes our robot a little different from the others is that it is truly modular; you can build a customized robot for every task almost as easily as you’re putting a Lego together,” Choset said. “No two ships are exactly the same, and in search-and-rescue, no two operations are ever exactly the same. Our robot, since it’s modular, we can change the robot in the field in real time.”

To create the underwater version of the robotic snake, the team used existing watertight modules that allow the robot to operate in bad conditions. Then they added new modules containing turbines and thrusters that allow the robot to maneuver underwater.

The team began working on the underwater robot snake last July. By last month, they had it swimming in the CMU pool.

The reason for this quick development, Choset said, is twofold.

“The number one reason why we were able to do this is because Carnegie Mellon just has great people, hard-working, dedicated, smart, creative people building wonderful devices.

“The second reason is because we’ve embraced this idea of modularity. They were able to build those modules by each group doing really well at one thing while understanding how their individual pieces mesh together.”

Choset said he’s still eager to continue improving the technology, noting that they may be able to produce underwater snake robots that are faster, lighter or cheaper.

“We would like it to be able to make it robust and accessible,” he said. “Robust meaning we can make it where it won’t break, and a person can drive it around as simply as a person driving a car. We also want to make it accessible so pretty much every ship in the Navy can have one.”

Choset said he also hopes that the technology will continue to serve new purposes.