Wrestling with robot snakes

Snake robots are not only cool, but potentially very useful. Most groups building them hope to send them into disaster zones to locate people stranded in fallen buildings. A robot with a snake-style body can climb over small and large obstacles, and wriggle through small gaps better than other type of robot.

But they are quite a handful to control ? as Johann Borenstein explained in his keynote speech at a recent meeting on rescue robotics. He built the snake robot in the video below ? called OmniTread ? and as you can see, it takes more than one operator to get it to climb through a fairly simple obstacle. I asked him a few questions about the challenge of operating snake robots.

NS: How many people are needed to control OmniTread?

JB: We currently need three operators. Each operator controls two joints of our six-joint OmniTread. Typically all joints need to be controlled at all times. Special cases [where only one controller is needed] such as driving straight along a long stretch of flat terrain, are rare.

NS: What do the operators have to do?

JB: Each joint has two degrees of freedom (i.e. controllable angles). Each operator controls one joint with one joystick on a commercial two-joystick game controller.

NS: Do all snake robots have this problem?

JB: Any snake-type robot that has many controllable joints will have that problem. It requires sophisticated software to address the very difficult control problem. I did develop a hardware-based control device that requires only one operator to control the OmniTread. A brief description of this unique device, called "Joysnake" is downloadable (pdf).



Source: www.newscientist.com