First wave-propelled robot swims, crawls and climbs using a single, small motor (w/video)

(Nanowerk News) The first single actuator wave-like robot (SAW) has been developed by engineers at Ben-Gurion University of the Negev (BGU). The 3D-printed robot can move forward or backward in a wave-like motion, moving much like a worm would in a perpendicular wave. SAW VIDEO
SAW can climb over obstacles or crawl through unstable terrain like sand, grass and gravel, reaching a top speed of 22.5 inches (57 centimeters) per second, five times faster than similar robots. Its minimalistic mechanical design produces an advancing sine wave with a large amplitude, using only a single motor with no internal straight spine. The breakthrough was published in Bioinspiration & Biomimetics ("Single actuator wave-like robot (SAW): design, modeling, and experiments").
SAW (single actuator wave-like robot) is the first robot that produces a pure wave-like motion with a single motor. The robot was developed for medical, industrial and search and rescue purposes. The design is simple, 3D printed and the passive wheels are for steering only. In the movie we show that the robot can crawl over different surfaces, climb and swim. It reached a maximum speed of 57 cm/s which is 5 times faster than any other similar robot. The robot's design is simply and highly reliable very little maintenance was needed. The robot's motion is similar to the "do the worm" dance.
"Researchers all over the world have been trying to create a wave movement for 90 years," says Dr. David Zarrouk, of BGU's Department of Mechanical Engineering, and head of the Bio-Inspired and Medical Robotics Lab.
"We succeeded by finding a simple, unique solution that enables the robot to be built in different sizes for different purposes. For example, it can be scaled up for search and rescue and maintenance, or miniaturized to a diameter of one centimeter or less to travel within the human body for medical purposes, such as imaging and biopsies of the digestive system."
The robot's innovative wave movement also enables it to climb through tunnels at a rate of eight centimeters per second when touching both sides. A waterproof version can swim at six centimeters per second. By adding spiny traction enhancers to each link, the team was able to propel the robot 13 percent faster than its own wave speed.
Dr. Zarrouk, who has been developing robots with a minimalistic and high-performance approach for many years, claims that SAW is easy to manufacture, strong, reliable, and energy efficient, which enables long-distance travel.
To find a way to replicate wave locomotion that mimics miniature biological systems, Zarrouk partnered with graduate students Ilanit Waksman, who researches swimming in viscous liquids (a movement that mimics small biological organisms) and Nir Dagani, who researches movement on flexible and slippery surfaces to model the locomotion of robots within the human body.
"The robot requires barely any maintenance, which is very unusual for an almost completely 3D-printed prototype that's this dynamic," Zarrouk says. "I believe it will be useful for traveling through the intestine for imaging and biopsies, and for infiltrating problematic, complex security areas, such as tunnels, destroyed buildings and pipes."
Source: American Associates, Ben-Gurion University of the Negev