Free installation method for GNSS/MEMS inertial combination navigation system

Abstract

The invention discloses a free installation method for a GNSS / MEMS inertial combination navigation system. The method is characterized in that an initial value of an installation error angle is assumed; under a static state, the gravity acceleration is projected to a coordinate system of an MEMS inertial sensor by using the initial value and compared with the filtered output value of an MEMS accelerometer and the output value of a gyroscope, so that the electrified zero offset of the MEMS accelerometer and the gyroscope can be estimated through decoupling; through filtering, the horizontal posture of the decoupling navigation is estimated, and the hypothesis value of the horizontal installation angle is gradually corrected, so that the estimated value is converged to a real horizontal installation angle; the speed information of the dynamic GNSS, the acceleration measurement information and the decoupled horizontal posture are utilized to establish the course of decoupling navigation of a filter, and the azimuth installation angle is corrected step by step; the installation angle change of the navigation system hardware equipment in the usage process is recognized through the measurement value of the gyroscope. According to the method, the on-line dynamic calibration of the inertial sensor can be rapidly completed.

Description

technical field [0001] The invention belongs to the technical field of inertial navigation and satellite navigation, and in particular relates to a free installation method of a GNSS / MEMS inertial integrated navigation system. Background technique [0002] The Beidou satellite navigation system is a major national strategy of our country. It is a global satellite-based navigation system (GNSS) that keeps pace with the US GPS, Russia's GLONASS and Europe's GALILEO. With the gradual improvement of the Beidou Phase III network deployment, the Beidou system is being gradually popularized and applied to various military and civilian carriers in the sea, land and air. The salient feature of the satellite navigation system is that it directly provides absolute positioning coordinates, and the error does not accumulate over time, but there are deficiencies that radio signals are easily blocked and interfered. The inertial navigation system (Inertial Navigation System, INS) can inde...

AI Technical Summary

Problems solved by technology

This method has the following disadvantages: first, the equipment is inconvenient to use, and it is not suitable for mass application of low-cost systems; second, the fault tolerance is poor, because the installation angle error is too dependent on the artificial offline measurement results, once an error or deviation occurs, it cannot Error correction; third, each device needs to calibrate the installation angle separately, which takes a long time to calibrate, and the cost of manpower and material resources is high; fourth, once the device is moved unintentionally, the installation angle needs to be re-measured; fifth, in order to accommodate the axial Consistent alignment, there are requirements for the reserved installation space of the carrier, and the versatility between different carriers is poor; sixth, some common carriers do not have the condition that the axis of the navigation device is consistent with the axis of the carrier, such as the round-trip of the railway transport carrier There will be an inconsistency of 180 degrees between the forward axis and the equipment axis, and there is no clear forward axis on the rotorcraft, etc.

To sum up, traditional equipment installation methods and technologies greatly limit the wide application of integrated navigation systems on various carriers

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