3D Measurement Using Line Laser and Stereo Camera with Background Subtraction.

In this paper, we propose a method to improve the accuracy of three-dimensional (3D) measurement with stereo camera by marking the measured object with a line laser. Stereo cameras are often used for 3D measurement. However, the search for corresponding points in the left and right images depends on the amount of texture of a measured object. In addition, devices using a monocular camera and a laser or an optical projector are often proposed for 3D measurement by image processing. However, these devices require precise calibration. Therefore, we previously developed a measurement system that combines a stereo camera and a line laser. This measurement system improved the accuracy of 3D measurement with a stereo camera by marking arbitrary points with a line laser and measuring those points, independent of the texture amount of the object to be measured. In addition, the line laser could be moved freely, eliminating the need for calibration with a stereo camera. In accuracy evaluation experiments, measurements on the order of millimeters were achieved. However, this method has issues with robustness and processing time. Therefore, we propose a new method using background subtraction that solves those issues in this paper.