Anisotropic Friction Skin for Holonomic Snake Robot Mobility*

Achieving effective locomotion for holonomic snake robots in diverse terrains for Search and Rescue (SAR) poses a significant challenge. While biological snakes exhibit complex mobility with the aid of anisotropic skin and a flexible body, replicating such capabilities in robotic systems demands specialised design considerations. This paper addresses designing and analysing anisotropic frictional skin to enhance the locomotion of holonomic snake robots in flat, variably friction environments. Two distinct frictional skins are developed and analysed through a peristaltic dynamic model. Moreover, comprehensive testing is conducted on various substrates to assess the effectiveness of the designed snakeskins. Experimental results indicate that a snake robot equipped with an interlocking-based skin on an Expanded Polystyrene substrate achieves small forward locomotion, while a Molecular Interaction-based skin enables sideways motion. This study provides insights into preliminary skin designs and locomotion tests conducted on flat surfaces, emphasising the need for further refinement to meet the demands of SAR applications.