A froglike robot capable of jumping has been designed by researchers at Harvard University. This soft-bodied device is capable of squeezing through tiny spaces, which could allow similar vehicles to explore disaster areas.
Soft-bodied robots are highly adaptable and able to sustain impacts without breaking. However, they are challenging to construct, as most motors, axles and batteries are rigid. Robots with hard bodies can be fast and powerful, but they can pose a danger in close quarters with humans.
Harvard University researchers combined elements of hard and soft robots in an effort to design an autonomous mechanism capable of traveling in dangerous territory, including disaster areas. A soft body combined with rigid structures was also shown to provide an ability for the device to survive impacts. A 3D printer was used to manufacture the robot, which features a body with varying degrees of rigidity. Most of the previous research on soft-bodied robots focused on devices with completely flexible structures.
"But for practical reasons, our soft robots typically have some rigid components — things like batteries and control electronics. This robot is a demonstration of a method to integrate the rigid components with the body of the soft robot through a gradient of material properties, eliminating an abrupt, hard-to-soft transition that is often a failure point," said Robert J. Wood from the Wyss Institute for Biologically Inspired Engineering at Harvard University.
The frog robot is printed as a single piece from a variety of materials to achieve the transitions in rigidity along the body. This characteristic, combined with the fact the device contains no parts that slide into or against each other, prevents the robot from becoming clogged with dirt, sand or debris. This could dramatically increase the survivability of the devices in disaster areas.
The core of the device contains a compressor, which drives a piston powering the robot. The gas fills one leg, tilting the device in the desired direction. Within the center of the engine, a combination of butane and oxygen is ignited, inflating the body of the robot, propelling the device into the air.
The robot is able to jump six times its body height vertically and half its body width horizontally.
"The robot's stiffness gradient allows it to withstand the impact of dozens of landings and to survive the combustion event required for jumping. Consequently, the robot not only shows improved overall robustness but can locomote much more quickly than traditional soft robots," Nicholas Bartlett, graduate student at the School of Engineering and Applied Sciences (SEAS), stated in a press release.
A video demonstrating the 3D-printed hybrid robot is available on the Harvard University YouTube channel.
Development of the frog-like robot was detailed in the journal Science.
