Coupled-drive-based joint design of a snake robot and its body-lifting method

Snake robots have very strong environmental adaptability. The locomotion and inspection of the robots depend upon their ability of climbing over obstacles and the lifting height. Especially in the rescuing application, the higher the robot can lift the more information can be obtained. A novel joint mechanism thus has been designed, that has 3 degrees of freedom among which 2 degrees of freedom are driven through a coupled drive. The snake robot composed of these joints can get a larger moment and a larger workspace. In this paper, we present the principle of the joint design that is based on a coupled drive, and introduce the lifting method of the snake robot and the effect of maximal joint angle α. Through analysis, we know that the number of units that the snake robot can possibly lift is the square of the number of units that the snake-like robot can directly lift. This is also confirmed by a simple example.