When disasters like earthquakes or bombings strike, rescuers are often faced with a problem: how to find survivors trapped deep within the wreckage without risking their own lives or making the situation worse for those still pinned in the rubble. The answer may be robotic animals that can venture to hard to reach places that are inaccessible to people.
Mother Nature as Muse
Robotic researchers are looking more and more to mimic nature for the shapes and functions of their mechanical creations. At North Carolina State University, when students were challenged to come up with a robot that could crawl through pipes, they looked to the animal world for a clue.
The idea came to Eddie Grant, director of the Center for Robotic and Intelligent Machines and a visiting professor at NC State, when he spoke with a major in the Marine Corps who had been called out to the Oklahoma City bombing. Grant realized that a robot that could navigate pipes would be ideal in this situation because pipes generally stay intact when the rest of a structure has collapsed.
"One of our interests in the laboratory is how biological systems can inspire robots, and when we came up with this idea for a robotic snake-like creature, we thought an inchworm-like mechanism would be good," says John Muth, one of the leaders of the project and a visiting professor at NC State. The senior design students created robots called MOCASIN I and MOCASIN II (Modular Observation Crawler And Sensing Instrument) that can crawl through six-inch piping.
How Does It Work?
MOCASIN II is a segmented robot that looks somewhat like an inchworm. It uses pneumatics (air pressure) to force padded "feet" against the pipe walls, contracting and expanding its "body" in the process. "The use of pneumatics for movement is an important factor because sometimes there are explosive gases present in buildings that have collapsed," says Grant. Since electricity might ignite the gases, the robot uses compressed air, which also allows it to run off of air tanks when no electricity is available. The robot is designed so that it breaks down into components that can be easily transported to remote sites, says Grant.
A tiny video camera and lights allow rescuers to see where MOCASIN II is located. The robot can also be equipped with sensors that could pick up vibrations from someone tapping on the pipes, or even "hear" voices and perhaps breathing.
What Else Could It Do?
|Gavin Millers snake robot.|
image: Gavin Miller
Robots like MOCASIN II could eventually have other uses, as well. They could be used for repairs in dangerous areas, such as nuclear power plant pipes, or to detect cracks in sewer or water lines. They could even be used on other planets.
Researchers at NASAs Ames Research Center are currently developing robots that resemble snakes to be used on the unknown terrain of other worlds. The snake-like design has several advantages. It allows the robots to be flexible and adaptable, plus they can fit into tight spaces and move over large objects. The Serpentine Robotics Project is working on adding pressure and light sensors to the robots as well. Like the MOCASIN, the robots use standard parts and electronics, but in this case they really resemble snakes. Animator Gavin Miller has developed robotic snakes that even imitate the slithering movement of the real thing.
While it may be a while before snakebots are used in space, rescuers on this planet are likely to find such robots an invaluable tool.