A newly developed underwater robot uses suction to hitch a ride.
A team at Beihang University in China has developed a remotely controlled underwater robot with a suction pad inspired by the slender sharksucker (or remora).
Measuring 13 centimetres across, such robots may be used to track and tag marine animals for study in the future. “Scientists could record data by attaching this robot to animals without hurting them,” said Li Wen, a robotics and biomechanics researcher at the university.
The suction pad of the robot contains some 1,000 small carbon fibre spinules arranged in rows. When attaching the device, these spinules are raised; to detach the device, the spinules are lowered.
Li Wen and his team tested the robot by attaching it to a range of different surfaces, including those that were rough, smooth, rigid and flexible.
They discovered that when it is underwater and attached to a smooth surface like plexiglass, the robot can withstand pull-off forces amounting to more than 340 times its own weight (approximately 436 newtons of force). For rougher surfaces like real sharkskin, it was lowered to 167 newtons of force.
This is certainly an important consideration in the robot’s construction, considering that some sharks can swim at speeds of more than 1.5 metres per second, and not always in a straight line.
A paper about the robotic tracker was published in a recent issue of Science Robotics.