A Simple Sand-skier with Internal Excitation

To achieve effective locomotion in granular environments, e.g. deserts, we introduce a simple sand-skier with internal excitation. This design diverges from conventional wheeled or tracked robots that face challenges in sandy terrains, due to the difficulty of creating anisotropicity. Drawing inspiration from animals such as the sand fish lizard, Atlantic razor clam, and Eunice aphroditois, our robot utilizes anisotropic structures to move through granular media. We first establish the modeling framework by deriving the motion equations that account for the robot's anisotropic frictional interactions with granular media. Subsequently, we implement a actuation strategy that leverages internal excitation mechanisms to induce asymmetric locomotion, enabling the robot to move effectively through granular media without conventional wheels or tracks. Numerical simulations validations demonstrate the robot's ability to adapt and move efficiently across various granular environments, showcasing its potential for applications in environmental monitoring, resource exploration, and disaster rescue.