A Comparison of Constant Curvature Forward Kinematics for Multisection Continuum Manipulators

Over the past few years, modeling of continuum robots has been the subject of considerable attention in the research community. In this paper, we compare a set of forward kinematic models developed for continuum robots, with the underlying assumption of piecewise constant curvature. A new approximate kinematic model based on phase and actuator length differences is also introduced for comparison. The comparative evaluation consists of computer simulation and physical experiments on a multisection continuum robotic manipulator, the OctArm. The experiments include both elongation and bending in 3D space. The comparative accuracy of the models is reported, along with relative numerical stability. Further conclusions are drawn on the applicability of the models to different real-world scenarios.