The latest robot prototypes developed at Harvard University are crawling their way around the Ivy League campus using skins made of snake scales.
Ahmad Rafsanjani, the postdoctoral researcher investigating the use of snake mobility models to applications in robotics has produced some extremely impressive trials of these winding robots.
Describing his methods for creating the robotic snakes, Rafsanjani explains that starting with familiar silicon rubber tubes, he stretched a synthetic snake skin composed of thin plastic materials that had been etched with various symmetric patterns of polygonal shapes.
Air was pumped into the silicone tubes beginning a cycle of inflation, followed by a resulting deflation. As the materials inflate, the etchings on the tubes expand and begin to resemble the skins of snakes, propelling the snake robot tube forwards.
As the tube deflates, the skin etchings return to being flush against the plastic film, resulting in the rear portion of the snake tube pulling itself forwards to the snake’s new position.
By repeating this process, the snake begins to propel itself forwards in a manner similar to an inching caterpillar.
To optimize the snake’s movement Rafsjanin experimented with different polygon etchings. The best results in terms of most movement per inflation/deflation cycle resulted from a trapezoidal pattern.
Excited about the prospects of their experimental findings, the journal Science Robotics published the study describing applications for the snakes in on rough surfaces such as concrete and asphalt as well as crawling through the human vascular system to deliver medications.
The idea of snake robots has been around for some time. The U.S. Army research lab had performed experiments in 2010 to create snake robot networks that worked together to manipulate objects in a manner akin to the coordinated tentacles of an octopus.
Broad military applications of this type of robotic system include grasping systems that can perform tasks that require delicate gripping and hand movements including turning and opening doors with knobs, not an easy feat for today’s robots.