Precise 3D positioning of a robotic arm using a single camera and a flat mirror

Abstract

A novel visual servoing structure is presented for robot positioning under an eye-to-hand camera configuration using panoramic vision. The proposed algorithm is based upon Image-Based Visual Servoing (IBVS) and uses only one fixed camera in conjunction with a stationary flat mirror. A single landmark mounted on the robot's end-effector along with its mirror reflection provide enough information for 3D reasoning based on a 2D image when viewed by a camera. The equations describing the relationship between the velocity of the coordinate frame attached to the robot's end-effector and rate of change in image features called the image Jacobian are presented. A novel set of image features that yields a rank-efficient image Jacobian is introduced. The Visual servoing based on an online estimation of the image Jacobian using a Kalman Filter (KF) is also presented. Simulated and experimental results illustrate the robustness of the proposed visual servoing structure. Sensitivity tests and analysis conducted through numerous experimentations show promising results.