Metrological Support of Video Measuring Systems

Test objects of various types are utilized in the creation and utilization of video measuring systems that are part of robots' technical vision, television sight units, triangulation measuring systems, as well as 3D scanners. Simultaneously, a specific test object was created for each type of device. This paper examines the possibility of creating and constructing universal test objects for calibration (verification) of 2D and 3D video measuring systems that are used to measure the geometric parameters of two-dimensional (2D) and three-dimensional (3D) objects, respectively. We suggest using a liquid crystal monitor-based test object (measure) to calibrate 2D systems. This measure is calibrated using a high-precision laser interferometer displacement measurement device and subpixel image resolution algorithms. The developed measure corresponds to the standard of the 3rd category according to the State verification scheme for measuring instruments of length in the range of 1∙10⁻⁹–100 m and wavelengths in the range of 0.2–50 μm. This measure can be used to determine the modulation transfer function of a video system and the point spread function. To calibrate (verify) 3D systems, a gage block stack that can move in space according to a given program using a translator and an external linear encoder is proposed. We present the technical specifications of the developed measures that can be used as working standards for the calibration (verification) of a wide variety of video measuring systems.