Set-based path following and obstacle avoidance for underwater snake robots

This article presents a set-based guidance strategy for path following with obstacle avoidance for underwater snake robots conducting planar sinusoidal motion. The guidance scheme is designed such that the robot follows a straight path and avoids obstacles on the way by following a circle around them. In order to enable a switching between these two tasks, we generalize a strategy that was introduced for surface vessels, by making the switching condition independent of the dynamics and thus applicable for a larger class of systems. The guidance system is shown to fulfill the control objectives at a kinematic level. We present new test results that validate the set-based guidance scheme for the first time experimentally.