4-legged robot that can climb walls and ceilings

Researchers have built a robot that can climb steep surfaces and walk upside down on ceilings thanks to materials and magnets.

The 4-legged robot moves on the wall. Photo: Science Robotics

A trio of researchers at the Korea Advanced Institute of Science and Technology, in collaboration with colleagues at the University of Illinois at Urbana-Champaign, designed and built a 4-legged robot with magnetic feet that can climb on walls and ceilings of buildings or structures constructed of metal. In a study published December 14 in the journal Science Robotics , Seungwoo Hong, Yong Um, Hae-Won Park and Jaejun Park describe the robot and how it behaves when tested in real-world conditions.

As the technology used to build robots improves, engineers find more ways to use them. In this new study, the team decided to build a robot that can assist in the maintenance of large metal structures such as bridges, oil tanks and some buildings. They created a 4-legged robot that can move on a flat surface, then approach a wall and climb up like a spider and continue crawling across the ceiling if needed.

The robot uses both magnetic elastomers and electromagnets. The design allows the robot feet to be magnetized and demagnetized as needed. Through it, the robot can put one foot in position on a vertical wall while the other foot is firmly attached, then release the foot to step by step. The team also programmed the robot to start climbing, then move around or over obstacles. To do so, they simulated how cats take small steps with their front paws to check the surface and then use their hind paws.

Test results show that the robot can climb on metal walls and walk upside down on the ceiling in the laboratory. It can also climb onto old outdoor tanks with rusty surfaces. The new robot can carry cargo weighing up to 3 kg and move at different speeds depending on the terrain with a maximum speed of 0.7 m/s.