Inspired by the behaviors of animals, the continuum robot provides superior
flexibility, deformability, and adaptability within a lightweight structure, making it
ideal for use in confined spaces. However, most continuum robots are designed for a
specific application and lack versatility and mobility due to their bulky actuation
system. This chapter introduces a portable tendon-driven continuum robot that, due to
its modular design, can be easily mounted on various rigid robot platforms, providing
additional manipulation capability and a larger workspace. In this design, 1) a
lightweight and portable structure that integrates the actuation units, control
electronics, and sensors into a compact tubular base; 2) a modularized actuator unit
with force sensing capability, are proposed. To test the portable continuum robot, the
actuation base is mounted on an industrial manipulator. Assisted by the rigid
manipulator, the continuum robot is used to inspect a pipeline with the robot body in a
compliant state using a closed-loop tendon force control. Finally, the experiments are
evaluated by the measured tendon forces and the images captured by an endoscope
camera placed inside a hollow flexible backbone. The results of the experiments show
that the proposed continuum robot can be used for pipe inspection and has considerable
potential for other applications. Moreover, the manipulation capability of a continuum
robot could be enhanced significantly by cooperatively working with a rigid
manipulator.
Keywords: Continuum robot, Constant curvature, Compliance, Cooperative manipulation, Force feedback control, Modularized actuator, Portable structure, Position control, Pipe inspection, Tendon-driven.
