# Fiber-Optic System for Monitoring Pit Collapse Prevention
## 2 Materials and Methods
### Hardware and Software  
The light spot contains a significant amount of noise, and the amount depends on the laser radiation stability and the ambient temperature. The OF has a stepped profile of the light spot, obeying the Gaussian distribution. The principle of data processing is to analyze the change in the profile of the light spot against the background of OF noise. Under mechanical action on the OF, the picture changes dramatically, which is perceived by the program, while the noise pollution is not taken into account. Great importance is given  
Figure 4: Graph obtained from the developed software, where 1 is the turnbuckle, 2 is the optical connector, 3 is the spring, 4 is the tension measurement instrument, 5 is the tension stud, 6 is the fiber -optic sensor of shift, 7 is the optical splitter, 8 is the optical power measurement instrument, 9 is the signal generator, 10 is the data processing device, 11 is the USB cable and 12 is the personal computer. to the hardware-software complex for data processing, which is able to exclude temporal fluctuations and track the rate of changing the transition of pixels from black to white. The hardware part of the system for monitoring the technical condition of the territory for mining operations using FOS was built on the principle of an open architecture and consists of three main parts: a coherent optical signal generator (laser), a FOS and a computing device that has the functions of receiving, processing and transmitting the data (Figure 5). Moreover, for the first two, well-known instruments were used, and the third part was built for the intellectual analysis in order to optimize the measurement process and costs. The first part of the system generates an optical signal. When propagating through the OF, it changes its properties. As a result, the pattern of the light spot incident on the photomatrix also changes. The number of pixels in the picture was chosen as the parameter under consideration. The second part measures the number of pixels of the light spot, the nature of which changes when exposed to the OF. As a result, a digital signal is generated at the output of the measuring part, which is then processed by the third part. The displacement value is determined, which is displayed on the program screen based on the obtained data. The image of the light spot at the output from the OF, shown in Figure 6, has a more illuminated region in the middle (1), in the interface (2) and in the region of losses emerging through the fiber cladding (3). A transition region is formed at the boundary, in which noise fluctuations are most clearly observed. These fluctuations can cause a violation of the adequacy of the obtained measurement data and cause a significant error in the obtained values. Software was developed in order to control the displacement parameters and to process them intelligently for improving the accuracy and reducing the likelihood of false alarms. The intelligence of the system lies in its ability to learn on the basis of the mechanical effects exerted on the FOS and make a decision on a warning alert about a  
Figure 5: Structural diagram of the monitoring system. Figure 6: The program’s appearance. possible violation of the integrity of the technological object. Moreover, it is possible to control the technical condition of up to several thousand reference stations simultaneously. However, the proposed algorithm is very complex. Thus, the cost of the device of the monitoring system is increased. It should be noted that the price also includes many years of research work. As a result, the fiber-optic monitoring system (FOSM) generates a fairly high cost. An important factor is also that the mining safety control system in open pits is currently not equipped to use more than four physical channels. The main reason for this shortcoming is limitation of the computing power of the computer and the performance of the video card.