The Design Of INS/GPS Navigation System Algorithms And Realization Of Display Control

Inertial navigation system has high navigation accuracy,it can update the navigation parameters fast,and it has high autonomy and concealment in navigation,but its errors will accumulate over time.GPS can give high-precision positioning and timing all over the world in navigation,but its function will be weakened and even invalidated when the weather is terrible or the signal is sheltered from high buildings.GPS and INS have excellent complementarity in navigation.when the visible stars are less than four,loose coupling combination of INS/GPS will be invalidated,This paper research on tightly coupled system of INS/GPS on engineering application,Extended Kalman filter is selected as the research object through theoretical analysis,and the simulation experiment and the static experiment of integrated navigation are carried out to verify the algorithm.Build the integrated navigation system model,and then derived state equation and measurement equation of the tight coupling model,the measurement equation is linearized according to EKF principle,then do matlab simulation experiment of integrated navigation system,calculate the navigation parameter through strapdown solution and EKF filter estimation,then use estimation correct the parameter,The simulation results show that the parameter error after filtering correction is much smaller than that of INS alone.and the combination state can still be achieved when the number of visible stars is less than four.It is proved that the effect of tightly coupled combination is better than that of INS navigation alone,and tightly coupled combination can still work in the combined state when the number of visible stars is less than four.Designed data receiving interface according to Qt framework,and used the interface collected INS data and GPS data simultaneously through serial communication.Choose and parse INS data and GPS data needed according to the respective protocol and then processed the data by strapdown algorithm and EKF separately,the results show that the filtered data can avoid error divergence and make the error fluctuate in a very small range,which further verifies the effectiveness of tight coupling,and proves the model of tightly coupled system and EKF algorithm are useful in engineering application.