Continuum Kinematics of a Planar Dual-Backbone Robot Based on Pseudo-Rigid-Body Model: Formulation, Accuracy, and Efficiency

摘要

This paper introduces a pseudo-rigid-body-model (PRBM) approach for analyzing the kinematics of a planar dual-backbone continuum robot. Unlike common load-displacement PRBM studies, the presented PRBM approach is tailor-made for the displacement-displacement analysis of compliant mechanisms, where the relationship between the lengths of the “backbone” wires and the pose of the robot is to be explored. Based on a PRB 3R modelling, the forward kinematics of the robot can be formulated as a nonlinear system of eight equations. To validate the accuracy and efficiency of the approach, a series of case studies are performed via ANSYS simulation and experiments. The results show that 1) the computation time for solving forward kinematics via the PRB 3R approach is less than 0.16% of that via ANSYS simulation; 2) the maximum percentage position errors of the PRB 3R model are 0.47% and 1.96% in the x- and y-directions, respectively; and 3) the maximum percentage orientation error of the PRB 3R model is 2.23%, as compared with ANSYS simulation results. As a result, the proposed PRBM approach delivers a satisfied compromise between accuracy and efficiency for the kinematic analysis of the planar dual-backbone continuum robot.