Improvement and Analysis of Kinematic Model for Cable-Driven Snake Manipulator Considering Cable Length Errors

In this paper, an improved kinematic model is proposed and analyzed for a cable-driven snake manipulator. Firstly, the fundamental motor-screw-cable cascaded driven characteristics are briefly described for this type of snake manipulator. Then, a theoretical kinematic model is established based on the D-H method. The coupling relationship between the ball screw error, cable flexibility error, and cable offset error of the manipulator is considered, and the reasons for these errors are specifically analyzed. The modeling of these errors and their impact on the cable length error are discussed, which serves as the theoretical foundation for improving the kinematic mapping relationship between cable length and joint angle. Finally, the joint angle and its error are simulated which consider the relationship between the ball screw error, cable flexibility error and cable offset error. The impacts of these errors on joint angle error are discussed separately, and the reasons are explained for these impacts.