Validation of Tumbling Robot Dynamics with Posture Manipulation for Closed-Loop Heading Angle Control

TL;DR

This paper introduces a validated reduced-order model for COBRA, a bio-inspired snake-like robot, enabling controlled tumbling for navigating rugged terrain and steep slopes, with potential improvements in stability and traction.

Contribution

It develops and validates a simplified dynamic model for COBRA's tumbling mode, enhancing understanding of its posture manipulation for terrain navigation.

Findings

Model accurately captures key dynamics of tumbling locomotion

Simulation results demonstrate effective heading and velocity control

COBRA's posture manipulation improves terrain adaptability

Abstract

Navigating rugged terrain and steep slopes is a challenge for mobile robots. Conventional legged and wheeled systems struggle with these environments due to limited traction and stability. Northeastern University's COBRA (Crater Observing Bio-inspired Rolling Articulator), a novel multi-modal snake-like robot, addresses these issues by combining traditional snake gaits for locomotion on flat and inclined surfaces with a tumbling mode for controlled descent on steep slopes. Through dynamic posture manipulation, COBRA can modulate its heading angle and velocity during tumbling. This paper presents a reduced-order cascade model for COBRA's tumbling locomotion and validates it against a high-fidelity rigid-body simulation, presenting simulation results that show that the model captures key system dynamics.