## 5 Experimental Testing (Setup)
#### Necessary Steps for Coordinates of the Sensed Object  
The following steps aim to describe and present the necessary activities and functions needed for the measurement realization. Firstly, both CCD camera system (initial) calibrations are essential, as illustrated in Figure 6. This step contains several subactivities such as the vision system startup followed by CCD camera system registration and the additional light source specification. After these subactivities, it is also necessary to realize and specify  
Figure 5: Incorrect procedures for determination of the sensed objects at the measured scene. Figure 6: Initial calibration of CCD cameras. the processing mode type required for the following processing. Finally, by setting the CCD camera system exposure time (in the case of more extended exposure time, the setting will be monitor blank), we achieve picture focusing using the actual light source conditions available in the working environment (together with the sensing object). With the help of an accurate digital measurement instrument (in the form of the digital caliper), we can determine the coordinates for the first calibration point, i.e.,: (\(x\) = 25 mm, \(y\) = 10 mm, \(z\) = 15 mm). Similarly, for the second calibration point the coordinates were: (\(x\) = 30 mm, \(y\) = 15 mm, \(z\) = 15 mm). In terms of calibration, two calibration points are sufficient because the magnification scale in axes \"\(x\)\" and \"\(y\)\" is the same. The additional step of the CCD camera system setting is object presence detection (if it is in the working envelope for both CCD cameras); see the left part of Figure 7. We use the density averaging function (that is inside the vision system) to determine the measurement area [31]. This function compares the two pictures' brightness and evaluates them based on the greyscale. Following this, we determine an overall brightness average with the measurement (firstly, for the empty area, and second for the area with the sensing object). The measurement realization verifies the sensing object detection (concerning the actual source light conditions). First, it evaluates an overall density average at the selected area (rectangle shape) that specifies a value of 74.451. The setting of the limit values for the density averaging function is carried out after this process is realized (based on the reliability of the sensing object presence or absence evaluation) [32]. Second, detection of the sensed object gives us qualitative information about errors from the measurement by the vision system. A failed measurement leads us to return to the initial calibration to perform recalibration; see failed detection example of a sensed object shown in the right part of Figure 7. An identification of coordinate axes \"\(x\)\" and \"\(y\)\" for the sensing object is demonstrated in the next  
Finally, the last step consists of determining the center of gravity parameters for the sensing object, which we choose by a simple mathematical operation (\(x\), \(y\), \(z/2\)) because we consider the center of gravity to be at the middle of the sensed object. Information obtained by this principle is then transferred into the computer via the RS232C serial interface for advanced processing (transformation of the coordinates from the external coordinate system to the coordinates of the robotic arm control system) [34]. Subactivities of this step include transmitting coordinate information directly to the control system of the robotic arm. We can state that a major influence on the captured results is the lighting conditions (light uniformity) or vertical camera system distance from the sensing object. Consequently, to verify obtained results, we carried out a test of normality [35]. We used a graphical test of normality to verify the normality, so-called quantile-quantile plot (\(Q\)-\(Q\) plot). If the obtained data are from the normal distribution, the points lie on a straight line for the coordinate axis \"\(x\)\" to be fulfilled.