Research On Real-time Positioning Communication System For In-pipe Detectors

Pipelines are an important way to transport energy,and their operational status is an important reflection of the country’s strategic level.However,due to the special service environment of the pipeline,irreversible defects may occur during service due to pipe manufacturing defects,mechanical damage,corrosion,etc.The expansion of pipeline defects during service can lead to pipeline failure,resulting in oil and gas leaks and even explosions,which can have catastrophic consequences.Therefore,it is significant to regularly inspect and secure pipelines.In-pipe inspection technology using in-pipe detectors as the carrier is the main way to detect defects in the current pipeline.And to complete the real-time tracking and positioning of the in-pipe detector is an important prerequisite to ensure the successful completion of the detection of the in-pipe detector.In the current ground engineering applications,still mainly in the detection process to manually track the collection and processing of data to obtain information on the location of the inner detector.This approach lacks real-time information and accuracy,and the workload of inspectors is large and time-consuming.Therefore,this thesis establishes a real-time positioning communication system for the inner detector of the pipeline,which is an important guarantee for pipeline safety inspection work and is of great significance for building an intelligent pipeline health monitoring system.This thesis develops a real-time positioning communication system for in-pipe detectors,which is designed to solve the problems of low efficiency of human tracking detectors on the ground and the inability to transmit location information in real time in the process of in-line pipeline inspection.This thesis analyzes the signal source and data transmission method of the communication network for real-time positioning of the detector in the pipeline,by combining the working principle of the detector in the pipeline and the very low frequency tracking and positioning technology.A variety of wireless communication technologies and wireless communication network networking modes are studied.By comparing and analyzing various communication technologies and networking methods,and combining the environment and communication requirements of long-distance oil and gas pipeline laying,Lo Ra wireless communication technology and Ad Hoc simple multi-hop networking mode are selected.This thesis simplifies the network structure.The overall network optimization is performed according to the application layer-network layer-MAC layer-PHY layer,resulting in the design of a system network model with a four-layer protocol stack.The network of real-time positioning communication system of in-pipe detector based on AODV routing protocol and Lo Ra WAN protocol is constructed.The research process of this thesis follows the route of theoretical research,system design,simulation analysis and experimental verification.Based on theoretical research and scheme design,this thesis builds a network simulation experimental system based on NS3 emulator,and builds a field test experimental platform based on STM32,Lo Ra module and Hall sensor.The experiments were conducted under different environmental and parameter conditions,respectively.The networking mode,node and network communication performance of the system designed in this thesis are tested experimentally.The results of simulation experiments and field experiments are as follows.In an urban environment with network interference,the effective communication distance between the nodes of the real-time communication system of the in-pipe detector designed in this thesis can reach200 m.In the open field environment,the effective communication distance between nodes can reach 500m;the effective transmission distance of multi-hop networking system network can reach 5Km,and the network transmission delay is 23 s.This thesis proposes a real-time positioning communication system for in-pipe detectors that can be transmitted over long distances and with low power consumption,as well as easy networking.The system designed in this thesis meets the expectations of the study,and its application to pipeline safety inspection projects can significantly improve the efficiency of in-pipe detector positioning tracking and data collection.