Exact Kinematic Modeling and Identification of Reconfigurable Cable-Driven Robots With Dual-Pulley Cable Guiding Mechanisms

Cable guiding mechanisms (CGMs) directly influence the reconfigurability of cable-driven parallel robots (CDPRs). But due to the complicated kinematic model of pulley-based CGMs, the velocity and acceleration mappings from the moving platform (MP) to the cables were unknown, the continuity of cable velocity, acceleration, and tension was unguaranteed, and the calibration pose-search method was based on inaccurate CGM models. In this paper, we establish an analytic and compact model for CGM. Based on this model, the velocity and acceleration mappings from the MP to the cables are derived. The continuities of cable trajectory and tension are proved. The exact identification Jacobian and its derivative are also formulated, leading to the increased fidelity of pose-search methods. The proposed method and formulations are verified by simulations and experiments on a redundant CDPR.