Snakebot

The SnakeBot, also known as a snake robot, is a biomorphic, hyper-redundant robot that resembles a biological snake. Snake robots come in many shapes and sizes, from as long as four stories (earthquake SnakeBot developed by SINTEF ) to a medical SnakeBot developed at Carnegie Mellon University that is thin enough to maneuver around organs inside a human chest cavity.

SnakeBots can vary greatly in size and design. Small cross-section-to-length ratios allow them to maneuver through tight spaces. Their ability to change the shape of their bodies allows them to climb stairs or tree trunks.

Many snake robots are constructed by chaining together several independent links. This redundancy can allow them to continue operating even after parts of their body are destroyed. Properties such as high terrainability, redundancy, and the ability to completely seal their bodies make snake robots notable for practical applications and as a research topic.

A SnakeBot differs from a snake-arm robot in that SnakeBots are usually self-contained, whereas snake-arm robots usually have remote mechanicals from the arm itself, possibly connected to a larger system.

Applications
SnakeBots are being developed to assist search and rescue, due to their ability to reach tight spaces that humans cannot, such as inside long thin pipes or environments cluttered with rubble.

Where SnakeBots mimic the slithering strategy of snakes, other rescue robots, such as the Deep Robotics X20, pursue strategies based on quadrupedalism. These strategies provide tradeoffs in different terrains.

Locomotion
Traditional SnakeBots move by changing the shape of their body, similar to actual snakes. Many variants have been created which use wheels or treads for movement. No SnakeBots have been developed yet that can completely match the locomotion of real snakes, but researchers have been able to produce new ways of moving that do not occur in nature.

In SnakeBot research, a gait is a periodic mode of locomotion. For example, sidewinding and lateral undulation are both gaits. SnakeBot gaits are often designed by investigating period changes to the shape of the robot. For example, a caterpillar moves by changing the shape of its body to match a sinusoidal wave. Similarly, a SnakeBot can move by adapting its shape to different periodic functions.

Sidewinder rattlesnakes can ascend sandy slopes by increasing the portion of their bodies in contact with the sand to match the reduced yielding force of the inclined sand, allowing them to ascend the maximum possible sand slope without slip. SnakeBots that sidewind can replicate this ascent.

Current research
SnakeBots are currently being researched as a new type of robotic, interplanetary probe by engineers at the NASA Ames Research Center. Software for SnakeBot is also being developed by NASA, so that they can learn by experiencing the skills to scale obstacles and remember the techniques.

Snake robots are also being developed for search and rescue purposes at Carnegie Mellon University's Biorobotics Lab.