Compound continuum manipulator for surgery: Efficient static-based kinematics.

BACKGROUND: The combination of various continuum manipulators is a potential solution to break the bottleneck of continuum manipulators. However, continuum manipulators dissatisfy the constant curvature assumption due to the influence of joints. METHODS: In this paper, a mechanics-based kinematic model of the compound continuum manipulator is proposed, which indicates that the curvature is non-constant. The static model of the manipulator is established, and the relationship of the bending angles is obtained. An efficient static-based Inverse Kinematic Algorithm using Polynomial Curve (IKAPC) of the manipulator is proposed. The polynomial curve is used to fit the end trajectory of the first manipulator. RESULTS: The simulation results show that the IKAPC is 354 times faster than the Levenberg-Marquardt algorithm. The experimental results show that the mechanics-based model improves the position accuracy by 3.75 times over the constant curvature method. CONCLUSION: This paper is critical for solving the inverse kinematics of the compound continuum manipulator.