## 3 Results
### Analysis of the Research Results  
Two cases were tested in the experimental studies. In the first case, the vehicle was parallel to the reference surface, and in the second case, the vehicle was not parallel to the reference surface (Figure 5). Figure 4: Automatic course correction algorithm. Figure 5: Parallel and non-parallel alignments of the AGV with respect to the reference surface. Figures 6 and 7 show the test runs, in which the automatic route correction was tested. In both cases, at the beginning of the vehicle's movement, the position of the trajectory actually realized by the vehicle does not coincide with the set trajectory. However, the computational process aimed at determining the course of the theoretical trajectory does not take errors into account, and the calculated trajectory coincides with the set one. This can be seen in both figures in the first eight meters of the distance traveled. In the first case, in Figure 6, the real motion trajectory is parallel to the originally set one. The vehicle axis is parallel to the given direction of movement. After measuring the distance from the base surface l, the first coordinate correction is made. After this correction, the vehicle changes its route, trying to return to the originally assumed trajectory. Distance measurements are taken and recorded throughout the entire movement. The use of these measurements for driving a vehicle along the assumed base surface can be observed only after covering the assumed section of the route necessary to return to the assumed trajectory. Figure 7 shows a situation in which the vehicle is not running parallel to the base surface. The trajectory calculated by the computer initially coincides with the given trajectory. Data from the laser rangefinder provide information regarding the actual course of the trajectory and indicate not only the shift, but also the angular deviation from the set route. Such a situation may take place each time, such as after the vehicle exits a turn or after long  
Figure 6: The courses of the real and theoretical trajectories with a parallel position. Figure 7: The courses of the real and theoretical trajectories with a non-parallel position. straight sections have been completed. In the example shown in Figure 7, the course angle and position are corrected. The conducted research on the automatic route correction was also aimed at determining the minimum section of the route necessary to travel along the adopted reference surface in order to set the vehicle axis parallel to the given surface. After correcting the course, the computer system needs to correct the coordinates used for the calculations and switch to driving the vehicle by odometry. The last position, as well as the angular position of the longitudinal axis of the vehicle in relation to the set trajectory along the distance of the movement at a constant distance from the base surface, is very important for the further course of the vehicle route. As shown in Figure 1, two characteristic points can be distinguished in the vehicle--point O, lying on the longitudinal axis of the vehicle between the driving wheels, and point W, also lying on the longitudinal axis of the vehicle 1 m from the O point towards the front of the vehicle. There is also a vertical axis, around which the whole vehicle rotates, passing through point O. The W point is the point that follows the trajectory. During the tests, between 9 and 12 m of the traveled route, the vehicle performed a curvilinear motion (Figure 8). The purpose of this movement was to guide the vehicle to a given trajectory and to pre-align the angular position of the vehicle axis with respect to the reference surface. During the curvilinear motion, the angle between the vehicle axis and the given direction changed. This angle can be determined from the trajectory courses of points W and O.