Design and evaluation of a continuum robot with extendable balloons

Abstract

In this thesis, a novel continuum robot actuated with extendable balloons is presented. The robot is composed of two parts; the tip and the exible shaft. The balloons are attached to the tip from their slack sections. The utilized balloons are able to extend much in length without having a signi cant change in diameter. Employing two balloons in an axially extendable, radially rigid exible shaft, radial strain becomes constricted; allowing free elongation. As in ated, the balloons apply a force on the wall of the tip, on which they are attached. This force pushes the tip forward, enabling the robot to elongate in longitudinal direction and take some of the slack back. The air is supplied to the balloons by an air compressor and its ow rate to each balloon can be independently controlled by solenoid valves via Pulse Width Modulation (PWM) signals. Changing the air volumes di erently in each balloon orients the robot, allowing navigation in substantially long and narrow environments. Mechanical properties of di erent balloons are analyzed during in ation. Afterwards, the robot is subjected to open eld and maze-like environment navigation tests. The proposed type of robots can be used in many applications such as exploratory or medical purposes by having necessary tools attached to the tip.