Rise of the bio-inspired soft robots

From the very beginnings of human advancement, people have taken countless cues from nature to invent and solve problems. The Egyptians are thought to have modeled the pyramid’s shape on the sun’s rays; Leonardo da Vinci studied birds and bats to create the first designs for his flying machine; and umbrellas originally mimicked the natural curvature of leaves and palms.

Inspired by the biomechanics of cheetahs, researchers developed a type of soft robot capable of moving more quickly — on solid surfaces or in the water — than previous generations of soft robots. Courtesy of North Carolina State University.

Biomimicry isn’t a shortcut — it’s an acknowledgment of the naturally occurring efficiencies around us. Recently, scientists from North Carolina State University leaned into that design philosophy with the development of a soft robot inspired by the animal kingdom’s fastest land animal: the cheetah.

The device is capable of moving more quickly, whether on solid surfaces or in the water, than previous generations of soft robots. Since cheetahs derive their speed and power from the flexing of their spines, the group focused on building a spring-powered, bistable spine — meaning that that robot has two stable states. The robot can switch between these states when air is rapidly pumped into its channels. This releases significant energy, allowing the robot to quickly exert force against the ground, causing it to gallop across whatever surface it finds itself on. And this is a big deal — previous soft robots have only crawled, remaining in contact with the ground at all times, which limited their speed.

Soft robotics is on the rise. Scientists at the University of Bristol are examining the potential for light-emitting soft robots and stretchable optoelectronics that can self-heal after becoming damaged. Others are working with soft actuator materials to create mobile organisms using light-responsive conducting polymers or photoresponsive gels. Additionally, work being done at Inha University, the University of Pittsburgh, and the Air Force Research Laboratory suggests that novel materials could be used to convert UV light into energy without the need for electronics, potentially providing a basis for a lightweight internal power source to mobilize robots efficiently without adding bulk.

Potential applications range across industries, but scientists note that search and rescue missions, where speed is absolutely essential, could greatly benefit from these new types of machines.

A light-powered soft robot for extreme conditions, even space? Stay tuned.