Snake Robot Gait Design for Climbing Eccentric Variable-Diameter Obstacles on High-Voltage Power Lines

This paper presents a novel gait design for serpentine robots to smoothly wrap around and traverse vibration-damping hammers along overhead power lines. Cubic quasi-uniform B-spline curves are utilized to seamlessly transition between helical segments of varying diameters during obstacle crossing, effectively reducing motion-induced impacts. The design begins by determining the control points of the B-spline curves to ensure posture continuity and prevent collisions with surrounding hardware obstacles, resulting in the derivation of an obstacle-crossing curve equation. Using this equation, the node coordinates and postures of individual robot units are computed, followed by the calculation of joint angles via inverse kinematics. A dual-chain Hopf oscillator is then employed to generate the obstacle-crossing gait. The feasibility of the proposed gait is validated through simulations in CoppeliaSim and Simulink, which model the robot’s motion as it wraps around and crosses eccentric obstacles with varying diameters. Additionally, a simulation platform is developed to analyze variations in joint angles and angular velocities during obstacle traversal. Results demonstrate that the gait, generated by combining cubic quasi-uniform B-spline curves with a dual-chain Hopf oscillator, achieves smooth and stable wrapping and crossing of vibration-damping hammers. The robot exhibits no abrupt changes in joint angles, smooth angular velocity profiles without sharp peaks, and impact-free joint interactions, ensuring reliable performance in complex environments.