Research On Low-cost SINS/Satellite Integrated Navigation System For Precise Guided Bomb

In this dissertation, design and research on low cost MEMS-SINS/Satellite integrated navigation system for precise guided bomb is deeply developed, which involves the algorithms research, the hardware system design, the software system realization, the engineering experiment and so on. The main work done in this thesis is as follows:(1) System calibration techniques have been discussed for MIMU, and a new calibration method of strapdown inertial measurement unit without north reference has been presented. The error model and basic algorithms of Strapdown Inertial Navigation System have been researched, including high-precision attitude matrix updating algorithms, velocity and position updating algorithms etc.(2) The loose coupling MINS/GPS integrated navigation system's algorithms have been researched. The observability analysis method of singular value decomposition theory has been studied in the system. Then an order filter for integrated system has been designed. The excellent result of computer simulation indicates that the order filter can reduce the filter calculation and the hardware cost.(3) The filter algorithms in tight coupling MINS/GPS integrated navigation system have been studied. The improved Kalman filter has been suggested to prevent distortion of filter. An improved SRUKF filter is designed according to the low-precise SINS/GPS integrated navigation system, the simulation results show that the improved SRUKF is more appropriate for the low-precise MINS/GPS system than EKF.(4) Owing to low-precise of the MEMS-SINS, it is impossible for the MINS/GPS integrated navigation system to work normally without GPS assistance.However, the GPS signal may be cut off by the U.S government once the war break out, so the guidance bomb shouldn't depend on GPS system completely. The information fusion of MINS/RDSS/GPS multi-sensor integrated navigation has been researched and an improved incoordinate interval federated filter has been proposed creatively. The new filter not only has the advantages of the incoordinate interval filter, which can solve the local filter's problem that the different navigation device measurements have different periods in real system ,but also has the advantages of preventing distortion of filter which caused by the imperfect arithmetic method or the incorrect statistical characteristic of noises.(5) According to the characteristic of the precise guided bomb, a MINS/GPS integrated navigation experimental prototype system which is based on a structure of floating point DSP+FPGA+MCU has been designed. The tasks of hardware system design, software system design and the code realization etc have been accomplished. Then, aiming at the asynchronism problem of GPS and SENS systems' output, a high-precision data synchronization method has been designed on its hardware platform.(6) Several experiments have been made to the experimental prototype system, such as three-axis turn table experiment, vehicle experiment, flight experiment, bomb-dropping experiment and so on.The excellent final results of these experiments indicate that the designed system for bomb has high accuracy and can satisfy the demands of the engineering application very well.