Abstract
We have been developing the three-dimensional measurement system using the camera image. This system is used a similar technique of the motion capture. In this measurement, the several markers are attached at the measured object and the luminous points in camera image are traced. The advantage of this measurement system is that the non-contact measurement and three-dimensional measurement is possible. In our three-dimensional measurement system, the measured target is the high brightness LED marker. The 3D position of the LED marker is calculated with the 2D positions in the camera screen coordinate. The LED marker in the camera image exists on some pixels, the position of the LED marker in the camera image is given by the luminance distribution of them. The position of the luminous point is obtained as the gravity center of light intensity, and the sub-pixel resolution is achieved. In this study, the influences of luminous marker conditions and calculation conditions on the measurement precision are investigated.