Design of Magnetic Continuum Robots with Tunable Force Response Using Rotational Ring Pairs
For medical robotics, this design allows online tuning of magnetic direction and intensity, potentially widening clinical applicability in both controllable and fixed magnetic fields.
This paper introduces a continuum robot design with tunable magnetic response at the tip, enabling steering without controlling external fields. Experiments show a max tip deflection of 33.8 mm (23% of robot length) and a mean absolute tip tracking error of 1.86 mm (1.2% of length).
In this paper, we discuss a novel continuum robot design that enables the online tuning of the magnetic response at its tip. The proposed method allows for the change of both effective magnetic direction and intensity, introducing steering DOF without the need to control the external fields. This is unattainable with classical designs, which rely on fixed internal magnetic content and steer solely under the effect of a controllable magnetic field. The proposed robot design can be used in both controllable and fixed magnetic fields, potentially widening the clinical applicability of these robots. We experimentally show a max tip deflection of 33.8 mm from the resting state (23 % of the length of the robot). We discuss a model based on modified beam theory that captures the mechanical behavior of the continuum robot, with a mean absolute tip tracking error of 1.86 mm (1.2 % of the length) and maximum errors of less than 4.8 mm (3.2 % of the length) for all experimental points.