Israeli engineers have developed one of the fastest amphibious robots

Robots moving both on land and on water can potentially be very useful, but they tend to be complex and rather slow. The new amphibious robot uses a relatively simple mechanism to move at a good speed.

Developed at Israel's Ben-Gurion University in the Negev, the AmphiSAW robot was inspired by how salamanders and snakes move through water, as well as how millipedes make their way across the ground.

The robot's body, mostly 3D-printed, consists of a head module at the front, a vertically wavy tail in the middle, as well as two floats and an electronically controlled steering wheel at the rear. Inside the head there are three motors, as well as a battery, a microcontroller, a GPS unit and a radio receiver.

The tail consists of a horizontal spiral resembling a corkscrew, which passes through the middle of 14 connected hollow lobed links. One of the engines in the head module rotates the spiral, forcing the links to move sequentially, creating a continuous series of sine waves that propagate along the entire length of the tail. This unique style of movement allows AmphiSAW to crawl on the ground at a speed of 1.5 body lengths per second, and swim on the surface of the water at a speed of 0.74 body lengths per second.

In this case, the robot's head can be equipped with two rotating wheels, which are independently driven by two other motors. In this configuration, the speed of movement on land increases by more than 2 times (4 body lengths per second) and the robot overcomes obstacles better. The swimming speed also increases by almost 50%. But these wheels increase resistance and consume a lot of energy when used in water, so they are not recommended for use in an aquatic environment.

The robot can be controlled in real time or programmed to follow a series of GPS points autonomously. According to scientists, the fast, but simple and inexpensive AmphiSAW boasts "the lowest cost of transportation among all amphibious robots described in the literature" (when used without additional wheels). The technology can be easily scaled up or down for use in areas such as search and rescue, marine research and aquaculture.