Pneumatic bladder links with wide range of motion joints for articulated inflatable robots

TL;DR

This paper introduces a novel inflatable robot design using pneumatic bladder links and Hillberry joints, enabling wide-range motion and demonstrating capabilities in payload handling and legged locomotion.

Contribution

It presents a new inflatable robot architecture with pneumatic bladder links and rolling contact joints, expanding motion range and application potential.

Findings

Achieved ±150° joint motion range, the largest among inflatable joints.

Successfully moved payloads up to 5 kg with a 2-DoF arm.

Demonstrated legged locomotion with inflatable structures.

Abstract

Exploration of various applications is the frontier of research on inflatable robots. We proposed an articulated robots consisting of multiple pneumatic bladder links connected by rolling contact joints called Hillberry joints. The bladder link is made of a double-layered structure of tarpaulin sheet and polyurethane sheet, which is both airtight and flexible in shape. The integration of the Hilberry joint into an inflatable robot is also a new approach. The rolling contact joint allows wide range of motion of $\pm 150 ^{\circ}$, the largest among the conventional inflatable joints. Using the proposed mechanism for inflatable robots, we demonstrated moving a 500 g payload with a 3-DoF arm and lifting 3.4 kg and 5 kg payloads with 2-DoF and 1-DoF arms, respectively. We also experimented with a single 3-DoF inflatable leg attached to a dolly to show that the proposed structure worked for legged locomotion.