  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.
