December 13, 2008 Researchers at the Robotics and Mechanisms Laboratory at Virginia Tech have designed a series of serpentine robots that are able to climb poles and inspect structures too dangerous or inaccessible for humans. The robots coil themselves around a beam and roll upward using an oscillating joint motion, gathering important structural data with cameras and sensors.
A 2006 US Bureau of Labor Statistics report listed 809 fatal falls from raised structures and scaffolding. The RoMeLa team hope that by increasing the use of autonomous robots in construction, humans can work in safer conditions. The HyDRAS models (Hyper-redundant Discrete Robotic Articulated Serpentine for climbing) use electric motors, while the CIRCA (Climbing Inspection Robot with Compressed Air) uses a compressed air muscle. Currently the robots are tethered to laptops, but future designs will incorporate a microprocessor and power source, allowing them to operate independently. All robots in the series are roughly three feet long, though the CIRCA is lighter than the HyDRAS.
Dennis Hong, director of Virginia Tech’s Robotics and Mechanisms Laboratory, said “The use of compressed air makes this approach feasible by enabling it to be light weight, providing compliant actuation force for generating the gripping force for traction, and allowing it to use a simple discrete control scheme to activate the muscles in a predetermined sequence.”
“These are really wicked cool robots,” Hong said. “Unlike inchworm type gaits often being developed for serpentine robot locomotion, this novel climbing gait requires the serpentine robot to wrap around the structure in a helical shape, and twist its whole body to climb or descend by rolling up or down the structure.”
The HyDRAS-Ascent, HyDRAS-Ascent II, and CIRCA recently earned recognition at the 2008 International Symposium on Educational Excellence.