Tracking control for snake robot joints

Abstract

Abstract-This paper considers the problem of model based control of the joints of a snake robot without wheels. The potential range of applications for snake robots are numerous, and delicate operations such as inspection and maintenance in industrial environments or performing search and rescue operations require precise control of a snake robot joints. To this end we present a controller that asymptotically stabilizes the joints of the snake robot to a desired reference trajectory. The controller is based on input-output linearization of a control plant model of the snake robot dynamics also developed in this paper. In addition, we provide a formal Lyapunov-based proof of the closed-loop stability, together with simulation results for a smooth dynamical model. Finally, the performance of the controller is tested on a non-smooth snake robot model with set-valued Coulomb friction that offers an accurate description of the stick-slip transitions during locomotion.

Controllability and Stability Analysis of Planar Snake Robot Locomotion

“…Nilsson [9] employed energy arguments to analyse planar snake locomotion with isotropic friction. Transeth et al [10] proved that the translational and rotational velocity of a planar snake robot is bounded. Li et al [11] studied the controllability of the joint motion of a snake robot, but they did not consider the position and orientation of the robot.…”

A survey on snake robot modeling and locomotion

“…Another benefit of employing these techniques is that many methods for accurately controlling robot manipulators now become available for snake robots. 109 However, a choice of minimal coordinates and a compliant contact force model renders the resulting set of equations of motion stiff and cumbersome to solve numerically. This is solved in parts by introducing nonminimal coordinates for a nonsmooth 3D model 110 where contact forces are modeled in a rigid-body setting and velocities are allowed to change instantaneously.…”

Experimental investigation of fundamental properties of snake robot locomotion

“…Note that α and ω are still independent parameters since any choice of α and ω can be obtained by choosing k αω = α 2 ω. Using (5), (6), and (10), and introducing the velocity state vector v = (v t , v n , v θ ) ∈ R 3 , the velocity dynamics can be written asv…”

“…Nilsson [5] employed energy arguments to analyse planar snake locomotion with isotropic friction. Transeth et al [6] proved that the velocity of a planar snake robot is bounded. Li et al [7] studied the controllability of the joint motion of a snake robot.…”