Framework for simulation-based control design evaluation for a snake robot as an example of a multibody robotic system

Snake robots are the multibody mechanisms allowing us to solve specific problems efficiently, i.e., navigate into diverse environments and maneuver through tight spaces or uneven grounds in a way that resembles living organisms. However, the path following and controlling such systems is challenging due to nonlinear dynamics, coupling between links, and nonstandard definitions of the set-point that differ from industrial applications. This paper describes a framework for simulation and evaluation of the controller design for snake robot as the set of tools for the 3D design and robot dynamic simulation. Combined with a theoretical background (equations of robot dynamics), it allows testing new solutions and strategies of robot control design. Firstly, based on the proposed methodology, we provide a mechanical design of a ten-link snake robot. We present control algorithms enabling point-to-point tracking of the robot position in two cases: (i) tracking the center of gravity of the robot and (ii) tracking the position of the head of the robot. Then we provide a simulation-based robustness analysis of a simple fault-tolerant control algorithm, where some snake robot joints are broken. The proposed framework can be used efficiently to study control strategies for multibody mechanisms.