Robust Deformation Model Approximation for Robotic Cable Manipulation Cable manipulation is a challenging task for robots. The major challenge is that cables have high degrees of freedom and are easy to deform during manipulation. In this paper, we propose a novel framework SPRRWLS to manipulate cables, which includes realtime cable tracking and robust local deformation model approximation. For cable tracking, structure preserved registration (SPR) is utilized to robustly estimate the movement of selected points on a cable even in the presence of sensor noise, outliers, and occlusions. Robust weighted least squares (RWLS) is then applied to calculate the local deformation model of the cable under uncertainties. We show that SPRRWLS enables the dualarm robots to manipulate cables with different thicknesses and lengths to different desired curvatures in multiple scenarios. We also show that realtime implementation of the proposed method can be simplified by parallel computation.

Influence of parameters uncertainties on the positioning of cabledriven parallel robots Positioning accuracy of cabledriven parallel robots is influenced by many factors such as geometry, actuator sensor accuracy and disturbances in the applied wrench. Another uncertainty source is the elasticity of the cables. While the influence of many factors may be decreased by calibration andor sensor fusion, elasticity parameters are difficult to estimate and their effect on the positioning errors has yet to be determined. In this paper we consider a generic cable model that includes cable elasticity and the effect of cable weight and we propose a generic algorithm that allows one to safely calculate the minimum and maximum of the positioning error at a given pose when the elasticity parameters are constrained to lie within some given bounds. The algorithm is designed for being able to manage the effect of different uncertainties sources and we compare the influence of elasticity versus the effect of uncertainties in the cable lengths.