Self-calibration Method Using Tension Sensors for a Vertical Planar Cable-Driven Parallel Robot

Authors are developing a high stiffness vertical planar cable-driven parallel robot capable of automating exterior wall inspections. Geometric parameter errors originating from the installation process can affect inspection results. Due to our robot's complex design, which results in an under-constrained system when faced with geometric parameter errors, traditional calibration methods fall short. To solve this problem, this paper proposed a new self-calibration method that use only internal sensors to minimize these errors. Firstly, we developed a kinematic model considering the structure of the special moving platform and pulleys. An error model based on the tension and length increments applied to the cables was developed. And with this error model, a self-calibration method is established. Finally, the proposed method was validated through simulation, demonstrating its effectiveness in reducing geometric parameter errors.