Research On The Methods For Real-time Realization Of The RLG Strapdown Inertial Navigation System Based On DSP

The Inertial Navigation System(INS) is needed for the vehicle detecting system with its realtime dynamic horizontal attitude,azimuth and position,so that the detecting system can compensate the detected results.The realtime property of the navigation parameters affects the compensated results directly,and will influence the precision of the target's location given by the detecting system.To this question,the thesis makes a research on the Ring Laser Gyro(RLG) Strapdown Inertial Navigation System(SINS), especially how to get the vehicle attitude and motion parameters in real-time,which is based on the high-speed digital signal processor DSP6713.The main work of this thesis is showed as follows:(1) The inconsistency between the low updating rate(100Hz) of the inertial navigation parameters and the high updating rate(1000Hz) of the attitude parameters needed by the detecting system has been solved in the thesis.Under the condition of Shannon sampling theory,an interpolation method is proposed.It shows that by swaying experiment on turntable and the experiment in outfield the method is feasible.(2) The thesis researches on the time-delay of the parameters given by the RLG SINS.The time-delay of the system includes the sampling time,the calculating time and the transmitting time.By experiment,the system time-delay is determined exactly.The errors led by time-delay are also analyzed and methods are proposed to reduce the influence.(3) Based on the high-speed signal processor DSP6713,the realtime realization of the algorithm for RLG SINS initial alignment is researched.Because of the vehicle perturbations,a coarse alignment and five-states Kalman Filter alignment scheme is made.According to the computation numbers and real-time desire of attitude updating, the specific force vector resolution and the Kalman filter initial alignment,the software is well configured to finish the initial alignment quickly in a high precision.(4) The real-time realization based on DSP6713 of locating algorithm of the RLG SINS integrated navigation is researched.The integrated navigation includes much navigation information and it is very important to mix it.The thesis discusses the pure inertial navigation position theory and the position errors.To achieve the position precision,both the odometer and landmark are used.The odometer parameters' on-line calibration,the SiNS/odometer integration method and the landmark correction method are also lucubrated and realized on the DSP6713 platform.The outfield experiment shows that the integrated navigation position error is limited under the guideline,and the software works well.(5) The real-time measurement of the vehicle movement parameters and attitude parameters is realized on the navigation-computing platform based on high-speed digital signal processor DSP6713.The lab experiment and the outfield experiment both tells that the system can satisfy the real-time desire,and the precision of initial alignment and integrated navigation can be well accepted.It is an important precondition of high precision vehicle detecting system.