Alignment method and system for movable base used for integrated navigation system

Abstract

The invention provides an alignment method and system for a movable base for an integrated navigation system. The method comprises the steps that firstly, navigation information and GPS observation information are obtained; secondly, an error model for alignment of the movable base is built; thirdly, a Kalman observation controller is built, wherein work of the Kalman observation controller is divided into multiple stages, and each stage corresponds to a state covariance matrix; fourthly, control gains of each stage are calculated through the Kalman observation controller based on the navigation information, the GPS observation information and the error model; fifthly, whether the control gains meet the Lyapunov stability condition or not is judged, if not, the third step is returned, and if yes, a compensation vector is calculated based on the control gains, the compensation vector is fed back to an inertial measurement unit, and the inertial measurement unit performs adjustment. According to the method, by the adoption of the Kalman observation controller, a navigation angle error can be lowered within a quite small range, and therefore alignment time is greatly reduced and alignment precision is improved.

Description

technical field [0001] The invention relates to the field of navigation systems, in particular to a method and system for aligning a moving base for an integrated navigation system. Background technique [0002] MEMS / GPS (Micro-Electro-Mechanical Systems Micro-Electro-Mechanical Systems / Global Positioning System Global Positioning System) integrated navigation system refers to the inertial measurement unit (IMU) based on MEMS technology as a sensor, and the GPS satellite navigation system for reference such as position and speed Information-assisted navigation system. Because of its small size, light weight, low power consumption and low cost, MEMS / GPS integrated navigation system has a good prospect in future vehicle and aviation applications. The self-alignment of the moving base refers to the method of completing the initial alignment of the system without relying on external information (such as the navigation information of high-precision inertial navigation) when the ...

AI Technical Summary

Problems solved by technology

This method can complete the alignment of the full angle range of 180°, but the modified error model is more complicated and the amount of calculation increases

Based on the revised heading angle error model, Hong uses the baseline method to solve the problem of large misalignment angles in the initial alignment, but the choice of baseline will affect the practicability of the alignment, and there are still requirements for the initial error

Crassidis proposes a nonlinear error model based on large misalignment angles, and uses trackless Kalman filtering to complete the alignment, but it is difficult to prove its stability theoretically without track filtering

Images