ARCSnake V2: An Amphibious Multi-Domain Screw-Propelled Snake-Like Robot

Robotic exploration in extreme environments such as caves, oceans, and planetary surfaces pose significant challenges, particularly in locomotion across diverse terrains. Conventional wheeled or legged robots often struggle in these contexts due to surface variability. This paper presents ARCSnake V2, an amphibious, screw propelled, snake like robot designed for teleoperated or autonomous locomotion across land, granular media, and aquatic environments. ARCSnake V2 combines the high mobility of hyper redundant snake robots with the terrain versatility of Archimedean screw propulsion. Key contributions include a water sealed mechanical design with serially linked screw and joint actuation, an integrated buoyancy control system, and teleoperation via a kinematically matched handheld controller. The robots design and control architecture enable multiple locomotion modes screwing, wheeling, and sidewinding with smooth transitions between them. Extensive experiments validate its underwater maneuverability, communication robustness, and force regulated actuation. These capabilities position ARCSnake V2 as a versatile platform for exploration, search and rescue, and environmental monitoring in multi domain settings.

NASU -- Novel Actuating Screw Unit: Origami-inspired Screw-based Propulsion on Mobile Ground Robots

Screw-based locomotion is a robust method of locomotion across a wide range of media including water, sand, and gravel. A challenge with screws is their significant number of impactful design parameters that affect locomotion performance in varying environments. One crucial parameter is the angle of attack, also referred to as the lead angle. The angle of attack has a significant impact on the screw's performance as it creates a trade-off between efficiency and forward velocity. This trend is consistent across various types of media. In this work, we present a Novel Actuating Screw Unit. It is the first screw-based propulsion design that enables the reconfiguration of the angle of attack dynamically for optimized locomotion across multiple media. The design is inspired by the kresling unit, which is a widespread mechanism in origami robotics, and the angle of attack is adjusted with a linear actuator, while the entire unit is spun on its axis as an archimedean screw. NASU is integrated onto a mobile test-bed and experiments are conducted in a large variety of media including gravel, grass, and sand. Our experiments show the proposed design is a promising direction for reconfigurable screws by allowing control to optimize for efficiency or velocity.