The Application Of SINS To Pipeline Defect Location Based On Optical Fiber Gyro

Oil and gas, and other energy as one of the main sources of industrial supplies, is closely related with the development of the national economy and people’s daily lives. As the number of oil and gas pipeline accidents is increasing year by year, the safety of the pipeline transportation has become the focus of people’s attention, which is the basis of where the pipeline safety detection technology comes from. In recent years, the inertial navigation system (INS) has made great progress in the civilian use-direction from military application,which largely promoted the development of the inertial navigation system applied to pipeline detection and location technology. Considering that using the inertial navigation system separately for navigation may cause the error divergence over time because of its shortcomings,and then may not meet the requirements of pipeline safety detection accuracy.This paper puts forward a design of locating system of pipeline defect detection, which is based on a kind of fiber optic gyro strapdown inertial navigation system (SINS).The process of design is to carry out the measured values,which from a set of Fiber optic gyro inertial measurement unit, for two groups of strapdown inertial navigation system algorithms respectively. We enable the strapdown inertial navigation system algorithm 1(SINS1) and dead reckoning (DR) for integrated navigation, in where the dead reckoning is based on the output distance information which from the odometers equipped on pipeline inspection carrier, and attitude information solved from strapdown inertial navigation system algorithm 1, and then regard the difference between location information calculated from strapdown inertial navigation system algorithm 1 and dead reckoning, as the observation to estimate and compensate the horizontal gyro drift and the attitude angle error by the use of Kalman filters, so as to achieve the objective of improving the positioning accuracy. Based on this integrated navigation,we add magnetic fixed-point signals to provide the external position information, to restrain the positioning error divergence of integrated navigation system with the position adjusting technology. In strapdown inertial navigation system the main reason caused errors accumulation is the presence of gyro drifts, but Kalman filter cannot estimate the vertical gyro drift,then in order to solve this problem,we propose the method of using the external position information provided by magnetic fixed-point signals and strapdown inertial navigation system algorithm 2 (SINS2) for system reset. The system reset technology could accomplish the estimation and compensation of Z axis gyro drift from strapdown inertial navigation system and the heading error precisely and finally meet the requirement of the positioning accuracy of pipeline defect safety detection.This paper completes the design of SINS/DR integrated navigation system and the position fixed technology. In addition, deduce the system reset technology which is based on the inertial coordinate of strapdown inertial navigation system. And finally verify the theoretical research on the design by the use of simulation experiments. Although the method and design of this paper have not been put into the practical application of locating system of pipeline defect detection, the research have enlightened and promoted the innovation and optimization of the locating system of pipeline defect detection to a certain extent.