Error suppressing method of rotary strap-down inertial navigation system based on space stabilization

Abstract

The invention provides an error suppressing method of a rotary strap-down inertial navigation system based on space stabilization. The error suppressing method comprises the following steps: determining an initial position parameter of a carrier through a GPS (global positioning system) and binding the initial position parameter of the carrier in a navigation computer; preparing to preheat a strap-down inertial navigation system, collecting data output by a fiber-optic gyroscope and a quartz accelerometer and processing the data; rotating an IMU (inertial measurement unit) and then converting the data generated by the fiber-optic gyroscope and the quartz accelerometer to be in a navigation coordinate system to obtain modulation format of constant deviation of an inertial unit; analyzing calibration factor error and installment error of the gyroscope in a modulation type inertial navigation system with steady space; and calculating attitude error caused by the calibration factor error and the installment error of the gyroscope during a conversion progress between a coordinate system of the IMU and the inertial system. With the adoption of the error suppressing method disclosed by the invention, constant deviation of inertial units in three-axis directions is modulated, and al the calibration factor error and the mounting error are also prevented from being coupled with the rotational angular velocity of the earth, consequently, the system has better stabilization, and navigation positioning precision is improved.

Description

(1) Technical field [0001] The invention relates to a measurement method, in particular to a space-stabilized rotation strapdown inertial navigation system error suppression method. (2) Background technology [0002] Space-stabilized inertial navigation system is also called analytical inertial navigation system. It has a gyro-stabilized platform, which is stable relative to the inertial space. It is a space-stabilized inertial platform realized by using the gyroscope to maintain the fixed axis in the inertial space and through three sets of servo systems. Three mutually perpendicular accelerometers are installed on the stable platform. Since the inertial platform has no rotational angular velocity relative to the inertial space, the accelerometer output signal does not have to cancel the effect of unwanted acceleration. Since the platform is stable in the inertial space, the component of the earth's gravity field vector in the inertial system changes at different position...

AI Technical Summary

Problems solved by technology

Since the photoelectric devices related to fiber optic gyroscopes cannot meet the overall requirements of gyroscope design in terms of technology and quantity, the development of fiber optic gyroscopes is limited, and the accuracy of existing fiber optic gyroscopes cannot meet the requirements of long endurance and high precision. It is very important to improve the navigation accuracy under the condition of existing gyro accuracy

Images