CObRaSO: Compliant Omni-Direction Bendable Hybrid Rigid and Soft OmniCrawler Module

TL;DR

This paper introduces CObRaSO, a novel omnidirectional bendable Omnicrawler module with hybrid soft-rigid structure, enabling versatile crawling and bending capabilities for various robotic applications, verified through simulations and experiments.

Contribution

The paper presents a unique design of an omnidirectional bendable Omnicrawler with hybrid soft-rigid structure, allowing passive conforming and active compliance in various configurations.

Findings

Successfully demonstrated omnidirectional bending and crawling in prototypes

Achieved versatile applications across pipeline, quadruped, and snake robots

Validated mobility and mechanism through simulations and real-world experiments

Abstract

This paper presents a novel design of an Omnidirectional bendable Omnicrawler module- CObRaSO. Along with the longitudinal crawling and sideways rolling motion, the performance of the OmniCrawler is further enhanced by the introduction of Omnidirectional bending within the module, which is the key contribution of this paper. The Omnidirectional bending is achieved by an arrangement of two independent 1-DOF joints aligned at 90? w.r.t each other. The unique characteristic of this module is its ability to crawl in Omnidirectionally bent configuration which is achieved by a novel design of a 2-DOF roller chain and a backbone of a hybrid structure of a soft-rigid material. This hybrid structure provides compliant pathways for the lug-chain assembly to passively conform with the orientation of the module and crawl in Omnidirectional bent configuration, which makes this module one of its kind. Furthermore, we show that the unique modular design of CObRaSO unveils its versatility by achieving active compliance on an uneven surface, demonstrating its applications in different robotic platforms (an in-pipeline robot, Quadruped and snake robot) and exhibiting hybrid locomotion modes in various configurations of the robots. The mechanism and mobility characteristics of the proposed module have been verified with the aid of simulations and experiments on real robot prototype.