## 1 Introduction  
Belt mistracking is excessive belt displacement towards one of the edges of the conveyor route under operating conditions [1]. It may cause a significant increase in operating costs due to accelerated belt and idler wear [2], increased energy consumption [3] and emergency stops [4]. It leads to the friction of the belt and the steel structure of the route, excessive delamination of the edges, damage to the core [5] or loss of strength properties and complete breaking [6]. The mistracking may also cause the transported material to spill into the location of rollers and pulleys, causing their damage and increasing the risk of fire due to friction of the belt and a faulty, blocked rotating element [7]. The centric running of the belt is also essential for the proper functioning of the cleaning devices and transfer point [8, 9]. The basic operation in the process of centering the belt is to remove the causes of the run-off, which is often a difficult task due to the possibility of several causes occurring at the same time [10]. One of the most common reasons for belt failure is the asymmetrical distribution of stresses in the belt, which is the result of improper operation of the tensioning mechanism [11]. An important factor affecting the state of belt tension is improper leveling of the route [12]. The degree of mistracking is also influenced by the wrong speed of the belt conveyor for specific operating conditions [13, 14]. Problems with the centric movement of the belt can also result from poor joint geometry or imperfections of the vulcanization process itself [15, 16] or uneven loading of material onto the belt at loading points, which results in additional lateral friction forces [17, 18, 19]. An important issue is the selection of an appropriate structural solution for loading points, which should consider individual design requirements for specific operating conditions, ensuring optimal material flow [20] or the use of devices mitigating the effects of this phenomenon, such as reinforced feed rollers or impact beds [21]. Lateral run-off of the belt may also be a consequence of excessive contamination of pulleys and rollers with material causing a one-sided increase in their diameter or failure to exercise due diligence when installing roller sets on the conveyor route [22]. In the case of belt conveyors operated in surface mining, atmospheric conditions, e.g., excessive crosswind [23] may be a determining factor in the formation of belt mistracking. The problems of belt mistracking on specific parts of the route are prophylactically reduced by precisely positioning the route segments and maintaining their axiality throughout the conveyor's lifetime [24]. A common way to ensure centric belt running is to adjust the angle of the rollers relative to the straight line perpendicular to the axis of the conveyor route [25; 26]. In the case of conveyors, where the belt for structural reasons tends to mistracking, it is worth using trough self-centering belt sets, which rotate automatically because of the pressure of the mistracked belt on the edge rollers or it is easier to use roller sets with tilt [27; 28; 29]. Standard solutions to protect the conveyor against belt lateral run-off also include safety switches that detect the presence of the belt outside the normal operating area or operate on the principle of direct contact of the belt and sensor [30]. Some non-destructive methods of monitoring the condition of the belts allow to simultaneously conclude about its correct course [31; 32; 33]. A good example is the methods of diagnostics of steel cord belts proposed in the work [34], based on the registration of magnetic field change. Another interesting solution is the belt edge detection system based on video image analysis [35]. However, the number of running monitoring solutions to detect belt movement imperfections well in advance is limited. The article presents the course of the conveyor belt operating parameters for normal conditions and simulated belt mistracking.