Research And Implementation Of MEMS-IMU Integrated Navigation System For Railway Location Network

Global navigation satellite system(GNSS)can provide long-term high-precision navigation and positioning information,but it is subject to external environmental interference,which will increase the positioning error,and even lose satellite signals and cannot locate.The strapdown inertial navigation system(SINS)is not affected by the external environment and has high precision in the short term.However,the positioning error will increase and accumulate over time,and cannot work alone for a long time.The GNSS / SINS integrated navigation system can use GNSS to overcome inertial guidance errors.The accumulated problems can also use SINS to make up for the shortcomings of GNSS signal failure in short-term,and the combination has the characteristics of low cost,miniaturization,and good dynamic performance.Therefore,it has a good application in military and civilian fields.This article relies on the research needs of the Chinese Academy of Sciences STS project to carry out research on MEMS-IMU integrated navigation systems.This paper first introduces the basic working principles of strapdown inertial navigation systems and satellite navigation systems.Then,the random error compensation method of MEMS gyroscope is studied.According to the problem that the MEMS gyroscope data drifts with time,the random error term of MEMS gyroscope is analyzed,a random error model is established,and an improved decoupling adaptive method is proposed.The Kalman filter algorithm performs noise reduction on MEMS gyroscope data.Through processing and analysis of the collected MEMS gyroscope actual measurement data,it shows that the proposed improved algorithm can better reduce the MEMS gyroscope random noise.Secondly,for Strapdown's problem that the inertial navigation system's longterm individual work positioning results are easy to divergence,the system's state equation is established by using the system error equation of strapdown inertial navigation,and the open-loop Kalman filter algorithm based on the indirect method is used.Perform location information fusion.In MATLAB,the trajectory of the carrier is simulated,and the simulation verifies the navigation and positioning characteristics of the strapdown inertial navigation system.Selecting different initial position errors,the experimental results show that the integrated navigation information fusion algorithm can stabilize and effectively improve the navigation performance.In addition,by simulating the intermittent failure of satellite signals,it is proved that the integrated navigation system algorithm has good feasibility.Finally,according to the positioning requirements of the railway location network,this paper realizes the location service of locomotives and vehicles based on the railway location information management system framework,and tests the system positioning functions.The experimental results show that the system has a good positioning effect and reliable trajectory tracking,realizing the real-time return of locomotive position information.The system can provide reliable location information services for railway information management.