Realtime locomotion control of a snakeboard robot based on a novel model, enabling better physical insights

Abstract

The snakeboard is a fascinating variation of the well-known classic skateboard, and a nonholonomic structure. Therefore, a snakeboard robot is appealing for usage in control engineering education. The propulsion, which relies on cyclic movements, resembles that of many biological creatures. Hence, the challenging snakeboard modelling and motion planning received much attention in literature during the last decades. Despite all these research efforts, there is no model available in which there is a clear link between the mathematical descriptions and physical phenomena. The lack of physical insights hampers the development of a closed-loop real-time trajectory controller which is apparent by the lack of literature on such algorithms for snakeboards. In this paper, the traditional models are rewritten to obtain a model with a clear link to physical phenomena. Based on this model a closed loop controller is designed. Moreover, this rewritten model delivers the insights on actuation efficiency which are used to adapt desired trajectories a priori to more energy-efficient forms. Finally, the control and trajectory optimisation is validated by measurements on a snakeboard robot.