Design And Implementation Of Beidou/SINS Tight Integrated Navigation System Based On DSP

With the development and improvement of China Beidou satellite navigation system,Beidou satellite navigation products are gradually applied in the fields of transportation,marine fishery,public security,fire prevention and disaster prevention and reduction.The Beidou/SINS integrated navigation system can make up for the shortcomings of a single navigation system and can improve the overall performance and stability of the navigation system.It is an important research and development direction in the Beidou industry.The goal of this thesis is to study the Beidou/SINS tightly coupled method with small dimension and easy implementation,and use the high-efficiency and stable data fusion algorithm to fuse the multi-sensor data in the combined system,and use the DSP chip as the processor core to realize the compact combination navigation system.Firstly,the DSP chip suitable for the tight couple of navigation algorithm is selected,and the realization scheme of the Beidou/SINS tight integrated navigation system based on multi-core DSP is proposed.Besides,The integrated navigation hardware system including Beidou satellite navigation receiver CNS200,micro inertial measurement unit ADIS16405,DSP development board and wireless transmission module was designed and built.Secondly,the derivation process of the mathematical model of Beidou/SINS tight integrated navigation system is studied.In order to reduce the computational burden of DSP,the system mathematical model is simplified,and a scheme of data fusion of attitude related information and pseudo-range and pseudo-range rate information is proposed by using two-stage filter.Thirdly,the adaptive CKF algorithm is used to fuse the attitude-related information from SINS,accelerometer and magnetometer,and the effectiveness of the filtering scheme and algorithm is verified by simulation experiments.The pseudo-range and pseudo-range rate tightly combined data fusion process of Beidou and SINS are studied.SCKF is used to fuse pseudo-range and pseudo-range rate data to ensure the accuracy and stability of data fusion algorithm in high-dimensional systems.Fourthly,the integrated navigation software is designed and embedded in TMS320C6748.According to the communication requirements and data processingrequirements of the system,the core assignment tasks are processed.The DSP core program,PRU0 core program and PRU1 core program are developed in the CCS development environment.Among them,the PRU0 core is responsible for collecting the original measurement data of the Beidou satellite navigation receiver,the PRU1 core is responsible for outputting the combined navigation result,and the DSP core is responsible for collecting the micro inertial measurement unit data,the Strapdown inertial navigation solution,the star selection and the data fusion.The update frequency of the output navigation data of Beidou/SINS tight integrated navigation system designed in this paper is 100 Hz.In order to verify its performance,experiments are carried out by means of turntable and car respectively.The experimental results show that the attitude angle error of the integrated navigation system is less than2°,the position error is less than 5.5 m,and the speed error is less than 0.3 m/s.The research results in this paper provide a way to build a high-precision,low-cost,and micro-small Beidou/SINS tight coupled integrated navigation system.