A new sand-diving robot based on the sandfish lizard has been developed by a team led by Daniel I. Goldman, a physicist at Georgia Institute of Technology.
The sandfish lizard tucks in its limbs and wiggles forward with a whole-body sinusoidal traveling wave motion. Take a look at this video to see how the robot imitates the living organism.
(Sandfish robot video)
the team built a 35-centimetre-long version of the robot, made from seven aluminium segments linked by six motors, all clothed in spandex to prevent the motors from becoming jammed.
The team then tested their robot by burying it in a container filled with plastic spheres 6 millimetres across. When the robot undulated its body at a frequency similar to the lizard, they found it could move forward at speeds of up to 0.3 body lengths per wave cycle - just below the 0.4 body lengths per cycle that a submerged lizard can achieve.
The intent is to create robots that can easily move through rubble to find and rescue people trapped in earthquakes or other catastrophes.
Science fiction writers (and readers) tend to find more sinister uses for robots that move easily through the earth and sand. For example, the claws from Philip K. Dick's 1953 story Second Variety are described burrowing upward from underground robotic factories - they "run and burrow."