Research On Align In Motion And Integrity Technology Of Civil Aircraft IRS/GNSS Integrated System

The inertial reference system is an important part of the civil aircraft avionics system.It can provide real-time information on the attitude,speed,and position of the aircraft.It is an important guarantee for safe flight of civil aircraft.With the further improvement of the safety requirements of civil aircraft,higher requirements have also been placed on the reliability of the inertial reference system.The two functions that the product needs to have are: the system has the ability to align in motion with the aid of external information;By combining with the satellite navigation system,the system has the integrity monitoring capability.This article focuses on the two points and provides technical support for advancing the domesticization of China's civil aircraft inertial reference system.According to the relevant standards and specifications of the new generation of air traffic management,this paper first analyzes the requirements of the civil aircraft on the inertial reference system.For the situation that the inertial reference system can not complete the navigation task alone during the approach phase,the idea of adopting a tightly combined structure for information fusion to enhance the adaptability of the navigation system is proposed.Then,the principle of the initial alignment of the traditional inertial reference system is analyzed,and the reason why the initial alignment cannot be completed by itself under the moving state is pointed out.Finally,the method of monitoring the integrity of the receiver is analyzed,and the main problems in the detection of double-star faults are pointed out.In view of the difficulty of obtaining the initial attitude angle of inertial navigation system in motion state,this paper proposes a method for obtaining the horizontal attitude by using the atmospheric data assisted inertial reference system,and then estimates the heading angle through the aircraft speed information obtained by the satellite navigation system,and solves the difficulty in obtaining the initial attitude of the sports situation.Finally,the factors that affect the accuracy of the aircraft motion alignment are analyzed.Aiming at the problem of difficulty in motion alignment in high latitudes,this paper design a reasonable motorized form to ensure that the inertial reference navigation system can obtain full navigation capability.Aiming at the situation that the traditional algorithm is not available for double star failure,the double star fault algorithm based on subset test is studied.The algorithm reduces the number of visible stars to five by the aid of inertial information.Finally,a method of system reconstruction based on observed satellite mass values is proposed,which reduces the impact of faulty satellites on normal satellites and ensures the navigation accuracy and reliability of civil aircraft.Finally,according to the modularization idea,a tight integrated motion alignment and fault detection simulation platform is built,and through the graphical interface tools to achieve the simulation interface simulation.Finally,the IRS module and the satellite receiver module are simulated respectively.The result is in line with the expectation to ensure the reliability of the simulation platform,and using the simulation platform built to verify the algorithm of the article design.