Analysis and heading control of continuum planar snake robot based on kinematics and a general solution thereof

This paper presents a kinematic calculation and control method for an inextensible continuum planar snake robot. The snake robot is assumed to move without side slipping; this constraint makes it easy to construct its kinematic model based on which we can analyze the movement of the robot. The kinematic model is expressed as a semi-linear partial differential equation (PDE). We discuss the general solution of the PDE and a calculation method based on it. However, the constraint also raises the problem of singular posture. The problem of singularities has been addressed for a snake robot with a serial link structure; however, for a continuum snake robot, much less research has been carried out. In this paper, we propose a method for controlling the direction of movement while avoiding singularities. The validity of our method is tested through simulations and experiments.

本文提出了一种不可拉伸平面连续型蛇形机器人的运动学计算与控制方法。假设该蛇形机器人运动时无侧滑，该约束条件可简化其运动学模型的构建过程，进而便于对机器人的运动进行分析。该运动学模型可表示为半线性偏微分方程（PDE），本文讨论了该PDE的通解及其对应的计算方法。然而，该约束条件同时也带来了奇异位形的问题。针对串联连杆结构的蛇形机器人，其奇异问题已有相关研究得以解决，但针对连续型蛇形机器人的相关研究却相对匮乏。本文提出了一种可在规避奇异位形的同时控制运动方向的方法，并通过仿真与实验验证了该方法的有效性。