The Humble Snail Inspired This Strong, Speedy, Single-Suction Cup Wall-Climbing Robot
Drawing no power at rest, this snailbot can climb walls and traverse ceilings thanks to a spray of water — equivalent to a snail's mucus.
A research team from the University of Bristol's robotics lab has taken inspiration from the humble snail to build a robot capable of climbing sheer surfaces — and even hanging upside-down — using a single sucker.
"People know that snails have a stable adhesive sliding behaviour, even though they are carrying a heavy payload, in this case a shell," explains Tianqi Yue, lead author on the paper detailing the slimy robot design. "Inspired by this, we presented a 'sliding suction' mechanism and developed a sliding suction robot, which achieved comparable sliding ability as snails."
Using the snail as its inspiration, the team developed a robot that has only a single sucker — yet can climb walls and slide along ceilings without losing its grip. The secret: a spritz of water, which serves as an analog of the snail's mucus and allows the suction mechanism to smoothly glide along surfaces.
The custom-built robot was proven experimentally, with the prototype proving able to carry payloads of up to 1kg (around 2.2lbs) in practice and up to 5kg (around 11lbs) theoretically, avoid obstacles as it moves around, and to operate at surprisingly high speeds. Perhaps the design's best feature, though, is that it only requires power when moving — and can remain at-rest, even upside down, while drawing no power at all.
"Through the performance of sliding suction robot, we demonstrated that sliding suction offers low energy consumption, high adhesion efficiency and safety, high loading capacity and low complexity, while only leaving a quick-to-evaporate water trail," Yue concludes. "The most exciting finding of our research it that the proposed sliding suction mechanism is a novel clean climbing strategy and will significantly advance the development of the next-generation climbing robots."
The team's work, which it hopes could be used to produce robots for inspecting wind turbine blades, ship hulls, aircraft, and skyscraper windows, is available in the journal Nature Communications under open-access terms.