Verification method of measurement error for relative displacement measurement system using a grid-attached method with a single camera

Abstract

A computation method of camera positions and posture information was proposed for a displacement measurement system using a grid-attached method with a single camera. The proposed method uses the colored 2D grid image to extract the origin image data and the grid image data and then computes the camera position and posture information using the conventional checkerboard calibration method. By applying the proposed method, the effects of the angle θ between the camera sightline and the normal vector of the measurement object on the measurement errors were investigated. The results showed that the measurement error was roughly constant in the range of θ < 45° whereas it tended to deteriorate rapidly in the range of 45° < θ < 55°.