Underwatertimes.com News Service - March 18, 2008 14:42 EST
crab robot explorer underwater

Crab robot. credit University of Bath

Underwater exploration may become easier in the future thanks to a new prototype crab-like robot invented by a University of Bath postgraduate student.

The robot can also move about on land and further development is planned for fully amphibious operation below water.

The technology has potential in the oil and gas industry, marine research or any companies that require independent underwater vehicles.

The design of the robot is closely based on the anatomy of crabs, animals that can walk both on land and underwater.

"Nature knows what works best and can be a source of inspiration for engineering design," said Charles Gage, the Biomimetics & Technical Creativity MSc student who developed the project.

"Crabs are perfect models for the kind of robot we wanted because they are 'tried and tested' amphibious vehicles.

"We studied the way crabs walk, their posture, gait and stride length. Then we applied this information on a model robot.

"The robot was built to copy the features of crabs with four pairs of legs divided in two halves.

"This biomimetic design is very stable, allows changes in direction and prevents mechanical interference between legs."

The robot can also vary its walking speed by changing stride length, just as crabs do in Nature, whilst maintaining the same motor speed.

"This unique approach makes this robot very energy-efficient," added Charles.

"We tested the crab robot on Minehead Beach in Somerset, England, in early September 2007.

"The robot performed exceptionally well and tackled the beach, scrambling over pebbles and small stones easily.

"The prototype was built with Lego Technic bricks to ensure simplicity,

"This can influence the future design and appeal to potential investors.

"There are a few toy robot on the market that look a lot like real crabs, but this robot is very different because it is built like a crab and walks like one."

Charles hopes to develop the design of the prototype to create a robot with full amphibious capabilities and improved stability under different conditions.

The MSc in Biomimetics & Technical Creativity is offered by the University of Bath's Department of Mechanical Engineering. Course information is available in the related links section.