Development Of Mine Bolt Length Online Detection System Based On FPGA

Aiming at the engineering quality and safety problems caused by the construction quality of bolts in underground coal mines,it has become an urgent engineering problem to be solved.Among them,whether the construction length of the bolt in the mine roadway reaches the design standard is an important part of the construction quality of the bolt.Bolt support has been widely used in the construction of the mine roadway,and the construction quality of the bolt directly determines the quality and safety of the tunnel engineering construction.In 2018,the National Coal Industry Association issued gbT35056-2018 standard,which is applicable to bolt support in coal mine roadway construction,and made detailed provisions on bolt support construction quality inspection.The national standard was implemented in December of the same year,including that bolt construction should meet the requirements of design geometric parameters.Due to the influence of artificial factors,the anchor rod construction is concealed,and the online measurement of the length of the anchor rod installation is paid more and more attention by the industrial production.There are some localities in the practical application of the existing detection methods,which reduces the measurement accuracy and efficiency of the anchor rod in the practical application.Therefore,the research and design of a mine bolt length detection system based on FPGA can accurately and efficiently measure the length of mine bolt,which has important reference significance for the construction quality detection method of mine roadway construction.Firstly,a large number of literatures are consulted to analyze the characteristics and shortcomings of the existing bolt length detection methods as well as the research status at home and abroad.The propagation and fluctuation theory of ultrasonic stress wave in one-dimensional rod and the propagation characteristic theory of stress wave are fully deduced and analyzed,and the detection principle of anchor length is summarized.Then,combining the existing detection methods and the detection scheme determined by this research topic,a mine anchor length detection system based on FPGA is studied and designed,including hardware system and software system.It is divided into two parts:the detection system based on FPGA,which is divided into ultrasonic stress wave excitation system and ultrasonic stress wave receiving system.The software program of DDS ultrasonic signal generator based on FPGA excitation system,14-bit DA signal output and lug are designed,And according to the power amplifier and transducer performance and requirements of the device parameters selection.The sensor,pre-amplifier circuit,two-stage voltage amplifier circuit,12-bit AD signal acquisition program,USB communication,SD card storage system are designed.Finally,Pearson cross-correlation algorithm is used to import the collected data of the signal receiving system into the MATLAB program for data signal processing.The propagation velocity of ultrasonic stress wave on the bolt can be calibrated by signal processing on the data collected from the bolt with known length.Similarly,cross-correlation analysis is carried out on the transmitted wave and echo signal on the bolt to obtain the time delay data and find out the unknown bolt length.Figure[51]Table[8]Reference[82]...