Self-Calibration of Cable Driven Continuum Robot

摘要

Continuum structured robot has been investigate in many years due to their highly flexible properties and high number of degrees of freedom (DOF). To address the strong compliance these robots are usually have low kinematic accuracy. In addition, the inevitable manufacturing tolerance, wear of connecting mechanisms will also resulting the geometric model deviate from their nominal values that will also produce errors. Therefore the identification of these errors for continuum robots is critical for the robots path planning and motion control tasks. This paper presents the self-calibration of a novel continuum cable driven robot. The proposed robot is designed as modularly with each joint module driven by four cables and sustained by a continuum center shut. The kinematics is analyzed and the self-calibration model has been proposed, the least-squares method is employed for the identification of the geometry errors, the calibration is only use the information of the cable length which can be read from its driven motor's encoders, and it does not require any external pose measurement devices. Computer simulation has been carried out to verify the proposed method which is shown that this method is convergence fast and it is able to identify out the geometric errors.