Earthworms are moving along the ground alternately squeezing and stretching the muscles along the length of their bodies, moving forward with each new wave of these movements. Snails and sea cucumbers also use this mechanism, called peristalsis to move forward. Our own gastro-intestinal tract function in much the same squeezing muscles along the esophagus to force the food toward the stomach.
Researchers at MIT, Harvard University and Seoul National University, have developed a soft robot that moves by peristalsis, crawling on surfaces, gripping segments of the body, like earthworms. This robot is made entirely of soft materials, incredibly tenacious, if stepped on or hit with a hammer, it will not do him any harm.
According Sangba Kim, professor of materials science from MIT, a soft robot can be used for the promotion of cross-country and is able to protiskivatsya through bottlenecks.
This robot is called Meshvorm (born "Meshworm"). Its artificial muscles are made from wire consisting of an alloy of nickel and titanium, which have shape memory and shrinks by heat. They have this wire wrapped around the tube, creating segments along its entire length, like the segments of the body of an earthworm. When exposed to a small current to the segments of wire, it shrinks and promotes the robot forward. The team published details of its structure in the journal IEEE / ASME Transactions on Mechatronics.
Over the past few decades, many robotics sought to create soft robotic systems, the shortcomings of their deprived bulky and fragile counterparts, which will explore remote places and overcome the bumpy territory. The soft exterior makes them safe for humans.
Built-in battery inside the tube and the circuit board, generate a current to heat the wire in certain segments of the body. Upon reaching a certain temperature, the wire body compresses the tube. Kim and his colleagues have developed algorithms to carefully control the heating and cooling of the wire, directing traffic directions given by the worm.
Furthermore, the robot is provided with longitudinal wires extending along its length, similar to the longitudinal muscle fibers earthworm. When heated, the longitudinal wire is compressed by turning the robot left or right.
This research was supported by the defense research agency DARPA.