Computer vision based calibration of the purely translational Orthopod manipulator

In this paper, we have achieved kinematic calibration of the purely translational Orthopod parallel mechanism via a flexible measuring system, which is based on Costar SI-M350 CCD camera with TEC-M12 lens. We first identify intrinsic parameters of the camera and the camera calibration result is verified using a simple yet practical experiment. Then we perform manipulator calibration using its inverse kinematics model. To evaluate the vision-based kinematic calibration method, we let the end-effector undergo a uniaxial translation and observe its leg parallelism. Experiment data verifies the effectiveness and flexibility of the proposed calibration method.