CN104101362B - Flexible SIMU system model based on-line compensation method for scale factors of gyroscope - Google Patents

Abstract

The invention discloses a flexible SIMU (Strapdown Inertial Measurement Unit) system model based on-line compensation method for scale factors of a gyroscope. The on-line compensation method comprises the following steps: removing the overloading influence of the specific force vector from the gyroscope output; conducting nonlinearity compensation on impulses output in unit time by a rolling channel, a yawing channel and a pitching channel of the gyroscope of the flexible SIMU system, so as to obtain the quantity of the impulses output in the unit time by the rolling channel, the yawing channel and the pitching channel of the gyroscope after the nonlinearity compensation and the deduction of the zero position and the acceleration overload item. By the adoption of the on-line compensation method, the accuracy of the impulses output in the unit time by the rolling channel, the yawing channel and the pitching channel of the gyroscope of the flexible SIMU system is improved, and the performance of the flexible SIMU is remarkably improved accordingly.

Description

Online compensation method for gyroscope scale factor based on flexible strapdown inertial unit system model

Technical Field

The invention relates to the technical field of flexible strapdown inertial unit system design, in particular to a gyroscope scale factor online compensation method based on a flexible strapdown inertial unit system model.

Background

The current practical nonlinear compensation of the flexible strapdown inertial measurement unit gyroscope is usually realized by adjusting the nonlinear degree of a single plate output at the rear stage of the gyroscope, the method is referred to as a hardware adjusting method for short in the following, the realization process is shown as the following figure 1, and the hardware adjusting method comprises the following steps: 1. assembling an inertial unit, 2, adjusting zero position and scale factor, 3, calibrating the inertial unit, testing the nonlinearity of the gyroscope, 4, detecting whether the nonlinearity of the gyroscope meets the requirement, and if not, adjusting the nonlinearity of a rear-stage single plate of the gyroscope to improve the nonlinearity of the scale factor of the gyroscope of the inertial unit. The hardware adjustment method has the following problems: firstly, after a calibration test, the inertial measurement unit needs to be uncapped again to adjust the matching resistance of a rear-stage single plate, so that the process is troublesome and misoperation is easy to occur; secondly, the precision level of the debugging resistor is low, and the long-term working precision of the gyroscope is influenced; and thirdly, the nonlinear compensation is difficult to realize, and the finally compensated gyro output still has large nonlinear error.

Disclosure of Invention

The invention aims to provide an online compensation method for a gyroscope scale factor based on a flexible strapdown inertial measurement unit system model, which can effectively and accurately perform online compensation on the nonlinearity characteristic of a gyroscope of the flexible strapdown inertial measurement unit system, perform real-time compensation on the nonlinearity of an inertial measurement unit gyroscope before the output of an inertial measurement unit and finally output the result to a navigation computer.

In order to achieve the purpose, the invention provides a gyro scale factor online compensation method based on a flexible strapdown inertial system model, which is characterized by comprising the following steps:

step 1: the computer in the flexible strapdown inertial unit system calculates the longitudinal pulse number NA of the flexible strapdown inertial unit system which is currently output in a preset unit time_x', normal pulse number NA_y' sum number of transverse pulses NA_ZObtaining a longitudinal acceleration Ax, a normal acceleration Ay and a transverse acceleration Az of a moving object carrying the flexible strapdown inertial unit system by using the following formula 1;

wherein,

k in the above-mentioned formula 1 and formula 2_1x、K_1y、K_1zRespectively calibrating the flexible strapdown inertial unit system by the inertial measurement combined test equipment to obtain scale factors output by a longitudinal accelerometer, a normal accelerometer and a transverse accelerometer in the flexible strapdown inertial unit system; k_y′x、K_z′x、K_x′y、K_z′y、K_x′z、K_y′zThe method is characterized in that the installation error coefficient of the accelerometer of the flexible strapdown inertial unit system is obtained by calibrating the flexible strapdown inertial unit system by the inertial measurement combination test equipment, wherein K_y′xIs a vertical installation error coefficient, K, of a longitudinal accelerometer in a flexible strapdown inertial unit system relative to a normal axis y' of a flexible strapdown inertial unit body_z′xIs a vertical installation error coefficient, K, of a longitudinal accelerometer in a flexible strapdown inertial unit system relative to a transverse axis z' of a flexible strapdown inertial unit body_x′yFor a normal accelerometer in a flexible strapdown inertial system to be relatively flexiblePerpendicular installation error coefficient, K, of the longitudinal axis x' of the connecting inertial unit body_z′yIs a vertical installation error coefficient, K, of a normal accelerometer relative to a transverse axis z' of a flexible strapdown inertial unit body in a flexible strapdown inertial unit system_x′zIs a vertical installation error coefficient, K, of a transverse accelerometer in a flexible strapdown inertial unit system relative to a longitudinal axis x' of a flexible strapdown inertial unit body_y′zIs a vertical installation error coefficient, K, of a transverse accelerometer in a flexible strapdown inertial unit system (1) relative to a normal axis y' of a flexible strapdown inertial unit body_0x、K_0y、K_0zRespectively calibrating the flexible strapdown inertial unit system by the inertial measurement combined test equipment to obtain zero-order errors of a longitudinal accelerometer, a normal accelerometer and a transverse accelerometer in the flexible strapdown inertial unit system;

the longitudinal pulse number NA of the flexible strapdown inertial unit system_x', normal pulse number NA_y' sum number of transverse pulses NA_ZThe method comprises the steps that the number of acceleration output pulses in the current unit time is obtained through calculation by a computer in the flexible strapdown inertial unit system;

step 2: obtaining the pulse number NW calculated in the flexible strapdown inertial unit system in unit time by using the following formula 3 according to the longitudinal acceleration Ax, the normal acceleration Ay and the transverse acceleration Az of a moving object carrying the flexible strapdown inertial unit system and after deducting a zero position and an acceleration overload term_x' after zero position and acceleration overload terms are deducted, pulse number NW obtained by calculation in unit time of gyroscope yaw channel of flexible strapdown inertial unit system_y' after zero position and acceleration overload terms are deducted, pulse number NW obtained by calculation in unit time of gyroscope pitching channel of flexible strapdown inertial unit system_z′：

In the above equation 3, NW_xCalculated for computer in current flexible strapdown inertial unit systemNumber of pulses NW per unit time of gyro-rolling channel of flexible strapdown inertial unit system_yThe number of pulses NW in unit time of a gyroscope yaw channel of the flexible strapdown inertial system is obtained by the computer in the flexible strapdown inertial system_zCalculating the number of pulses in a unit time of a gyroscope pitching channel of the flexible strapdown inertial unit system obtained by a computer in the flexible strapdown inertial unit system; e_1xScaling factor, E, of a gyroscope rolling channel output of a flexible strapdown inertial unit system obtained by calibrating the flexible strapdown inertial unit system by an inertial measurement unit testing device_1yScaling factor, E, of a gyroscope yaw channel output of a flexible strapdown inertial unit system obtained by calibrating the flexible strapdown inertial unit system by an inertial measurement unit testing device_1zThe calibration factor is the scale factor output by a gyroscope pitching channel of the flexible strapdown inertial unit system obtained by calibrating the flexible strapdown inertial unit system by the inertial measurement combined test equipment; d_0xZero pulse output for a gyro rolling channel of a flexible strapdown inertial unit system obtained by calibrating the flexible strapdown inertial unit system by an inertial measurement unit testing device, D_0yZero pulse output for a gyroscope yaw channel of a flexible strapdown inertial system obtained by calibrating the flexible strapdown inertial system with an inertial measurement unit testing device, D_0zOutputting zero pulse of a gyroscope pitching channel of the flexible strapdown inertial unit system obtained by calibrating the flexible strapdown inertial unit system by the inertial measurement combined test equipment; d_1xThe coefficient of influence of longitudinal acceleration on a gyroscope rolling channel of the flexible strapdown inertial unit system is obtained by calibrating the flexible strapdown inertial unit system by the inertial measurement combined test equipment, D_1yThe coefficient of influence of longitudinal acceleration on a gyroscope yaw channel of the flexible strapdown inertial unit system is obtained by calibrating the flexible strapdown inertial unit system by the inertial measurement combined test equipment, D_1zThe method is characterized in that the method is a coefficient of influence of longitudinal acceleration on a gyroscope pitching channel of the flexible strapdown inertial unit system, which is obtained by calibrating the flexible strapdown inertial unit system by an inertial measurement combined test device; d_2xThe method is characterized in that the gyro rolling channel of the flexible strapdown inertial unit system is subjected to normal addition, and the flexible strapdown inertial unit system is calibrated by the inertial measurement combined test equipmentCoefficient of influence of speed, D_2yThe influence coefficient of normal acceleration on a gyroscope yaw channel of the flexible strapdown inertial unit system is obtained by calibrating the flexible strapdown inertial unit system by the inertial measurement combined test equipment, D_2zThe method is characterized in that the method is a gyroscope pitching channel normal acceleration influence coefficient of the flexible strapdown inertial unit system obtained by calibrating the flexible strapdown inertial unit system by an inertial measurement combined test device; d_3xThe coefficient of influence of the transverse acceleration on the gyro rolling channel of the flexible strapdown inertial unit system is obtained by calibrating the flexible strapdown inertial unit system by the inertial measurement combination test equipment, D_3yThe coefficient of influence of lateral acceleration on a gyroscope yaw channel of the flexible strapdown inertial unit system is obtained by calibrating the flexible strapdown inertial unit system by the inertial measurement combined test equipment, D_3zThe method is characterized in that the method is a coefficient of influence of lateral acceleration on a gyroscope pitching channel of the flexible strapdown inertial unit system, which is obtained by calibrating the flexible strapdown inertial unit system by an inertial measurement combined test device;

and step 3: in the flexible strapdown inertial unit system, the pulse number NW within the unit time of the gyroscope rolling channel of the flexible strapdown inertial unit system obtained in the step 2 after zero position and acceleration overload terms are deducted_x', deduct the pulse number NW in unit time of the gyro yaw channel of the flexible strapdown inertial unit system after zero position and acceleration overload term_y' number NW of pulses in unit time of gyroscope pitching channel of flexible strapdown inertial unit system after deducting zero position and acceleration overload terms_zRespectively carrying out the existing nonlinear compensation to obtain the pulse number NW output in unit time of the rolling channel of the gyroscope after the nonlinear compensation and deduction of zero position and acceleration overload terms_xThe number NW of pulses output by the gyroscope yaw channel in unit time after nonlinear compensation and zero position and acceleration overload term deduction_yThe number NW of pulses output by the gyroscope pitch channel in unit time after nonlinear compensation and zero position and acceleration overload term deduction_z″；

And 4, step 4: NW obtained from step 3 in flexible strapdown inertial unit system_x″、NW_y"and NW_z"obtaining compensated gyro rolling channel induced output pulse number NW of flexible strapdown inertial unit system by following formula 4_bxAnd the compensated gyroscope yaw channel induction output pulse number NW of the flexible strapdown inertial unit system_byAnd the compensated gyroscope pitching channel induction output pulse number NW of the flexible strapdown inertial unit system_bz:

Wherein E is_1xScaling factor, E, of a gyroscope rolling channel output of a flexible strapdown inertial unit system obtained by calibrating the flexible strapdown inertial unit system by an inertial measurement unit testing device_1yScaling factor, E, of a gyroscope yaw channel output of a flexible strapdown inertial unit system obtained by calibrating the flexible strapdown inertial unit system by an inertial measurement unit testing device_1zThe calibration factor is the scale factor output by a gyroscope pitching channel of the flexible strapdown inertial unit system obtained by calibrating the flexible strapdown inertial unit system by the inertial measurement combined test equipment; d_0xZero pulse output for a gyro rolling channel of a flexible strapdown inertial unit system obtained by calibrating the flexible strapdown inertial unit system by an inertial measurement unit testing device, D_0yZero pulse output for a gyroscope yaw channel of a flexible strapdown inertial system obtained by calibrating the flexible strapdown inertial system with an inertial measurement unit testing device, D_0zOutputting zero pulse of a gyroscope pitching channel of the flexible strapdown inertial unit system obtained by calibrating the flexible strapdown inertial unit system by the inertial measurement combined test equipment; d_1xThe coefficient of influence of longitudinal acceleration on a gyroscope rolling channel of the flexible strapdown inertial unit system is obtained by calibrating the flexible strapdown inertial unit system by the inertial measurement combined test equipment, D_1yThe coefficient of influence of longitudinal acceleration on a gyroscope yaw channel of the flexible strapdown inertial unit system is obtained by calibrating the flexible strapdown inertial unit system by the inertial measurement combined test equipment, D_1zThe flexible strapdown inertial unit is obtained by calibrating a flexible strapdown inertial unit system by an inertial measurement combination test deviceThe gyroscope pitching channel of the system is influenced by the influence coefficient of longitudinal acceleration; d_2xThe influence coefficient of normal acceleration on a gyroscope rolling channel of the flexible strapdown inertial unit system is obtained by calibrating the flexible strapdown inertial unit system by the inertial measurement combined test equipment, D_2yThe influence coefficient of normal acceleration on a gyroscope yaw channel of the flexible strapdown inertial unit system is obtained by calibrating the flexible strapdown inertial unit system by the inertial measurement combined test equipment, D_2zThe method is characterized in that the method is a gyroscope pitching channel normal acceleration influence coefficient of the flexible strapdown inertial unit system obtained by calibrating the flexible strapdown inertial unit system by an inertial measurement combined test device; d_3xThe coefficient of influence of the transverse acceleration on the gyro rolling channel of the flexible strapdown inertial unit system is obtained by calibrating the flexible strapdown inertial unit system by the inertial measurement combination test equipment, D_3yThe coefficient of influence of lateral acceleration on a gyroscope yaw channel of the flexible strapdown inertial unit system is obtained by calibrating the flexible strapdown inertial unit system by the inertial measurement combined test equipment, D_3zThe method is characterized in that the method is a coefficient of influence of lateral acceleration on a gyroscope pitching channel of the flexible strapdown inertial unit system, which is obtained by calibrating the flexible strapdown inertial unit system by an inertial measurement combined test device; ax is a longitudinal acceleration of a moving object carrying the flexible strapdown inertial unit system, Ay is a normal acceleration of the moving object carrying the flexible strapdown inertial unit system, and Az is a lateral acceleration of the moving object carrying the flexible strapdown inertial unit system.

The invention eliminates the acceleration overload influence from the gyroscope output (zero position and acceleration overload item deduction), then carries out nonlinear compensation on the pulse number output in unit time of the gyroscope rolling channel, the yaw channel and the pitch channel of the flexible strapdown inertial unit system to obtain the pulse number output in unit time of the gyroscope rolling channel, the yaw channel and the pitch channel after the nonlinear compensation and the zero position and acceleration overload item deduction, and finally restores the output. Thereby improving the output precision of a gyro rolling channel, a yaw channel and a pitch channel of the flexible strapdown inertial unit system. The reason is that the output of a flexible gyroscope includes sensitivity not only to angular velocity changes but also to acceleration overload shocks. The acceleration overload influence is eliminated firstly and then nonlinear compensation is carried out, so that larger errors are avoided, and finally the performance of the flexible inertial unit is improved remarkably.

Drawings

FIG. 1 is a basic flow chart of compensation of nonlinearity of a flexible inertial measurement unit gyroscope by a current general hardware adjustment method;

FIG. 2 is a schematic structural view of the present invention;

wherein, 1-flexible strapdown inertial unit system, 2-inertia test equipment.

Detailed Description

The invention is described in further detail below with reference to the following figures and specific examples:

a gyro scale factor online compensation method based on a flexible strapdown inertial system model is characterized by comprising the following steps:

step 1: the computer in the flexible strapdown inertial system 1 calculates the longitudinal pulse number NA of the currently output flexible strapdown inertial system 1 in a preset unit time_x', normal pulse number NA_y' sum number of transverse pulses NA_ZObtaining a longitudinal acceleration Ax, a normal acceleration Ay and a transverse acceleration Az of a moving object carrying the flexible strapdown inertial unit system 1 by using the following formula 1; the formula I is obtained by deducing a mathematical model of a strapdown flexible inertial measurement combination; the mathematical model can refer to 'research on inertia measurement combination rapid test method' of Von Bow, Gu Feng, etc., and derive the influence coefficient of the yaw rate on the rolling channel, the influence coefficient of the pitch rate on the rolling channel, the influence coefficient of the roll rate on the yaw channel, the influence coefficient of the pitch rate on the yaw channel, the influence coefficient of the roll rate on the pitch channel and the influence of the yaw rate on the pitch channelThe sound coefficient ignores the influence through the guarantee of the installation of the flexible strapdown inertial unit system 1, thereby obtaining a formula 1;

wherein,

k in the above-mentioned formula 1 and formula 2_1x、K_1y、K_1zThe calibration factors output by a longitudinal accelerometer, a normal accelerometer and a transverse accelerometer in the flexible strapdown inertial system 1 are respectively obtained by calibrating the flexible strapdown inertial system 1 by the inertial measurement combined test equipment 2; k_y′x、K_z′x、K_x′y、K_z′y、K_x′z、K_y′zThe installation error coefficient of the accelerometer of the flexible strapdown inertial system 1 is obtained by calibrating the flexible strapdown inertial system 1 by the inertial measurement combination test equipment 2, wherein K_y′xIs a vertical installation error coefficient, K, of a longitudinal accelerometer in the flexible strapdown inertial unit system 1 relative to a normal axis y' of a flexible strapdown inertial unit body_z′xIs a vertical installation error coefficient, K, of a longitudinal accelerometer in the flexible strapdown inertial unit system 1 relative to a transverse axis z' of a flexible strapdown inertial unit body_x′yIs a vertical installation error coefficient, K, of a normal accelerometer in the flexible strapdown inertial unit system 1 relative to a longitudinal axis x' of a flexible strapdown inertial unit body_z′yIs a vertical installation error coefficient, K, of a normal accelerometer in the flexible strapdown inertial unit system 1 relative to a transverse axis z' of a flexible strapdown inertial unit body_x′zIs a vertical installation error coefficient, K, of a transverse accelerometer in the flexible strapdown inertial unit system 1 relative to a longitudinal axis x' of a flexible strapdown inertial unit body_y′zIs a vertical installation error coefficient, K, of a transverse accelerometer in the flexible strapdown inertial unit system 1 relative to a normal axis y' of a flexible strapdown inertial unit body_0x、K_0y、K_0zRespectively obtaining zero-order errors of a longitudinal accelerometer, a normal accelerometer and a transverse accelerometer in the flexible strapdown inertial system 1 by calibrating the flexible strapdown inertial system 1 by the inertial measurement combined test equipment 2;

the longitudinal pulse number NA of the flexible strapdown inertial unit system 1_x', normal pulse number NA_y' sum number of transverse pulses NA_ZThe method comprises the steps that the number of acceleration output pulses in the current unit time is obtained through calculation by a computer in the flexible strapdown inertial unit system 1;

step 2: obtaining the pulse number NW calculated in the flexible strapdown inertial unit system 1 in unit time by using the following formula 3 according to the longitudinal acceleration Ax, the normal acceleration Ay and the transverse acceleration Az of a moving object carrying the flexible strapdown inertial unit system 1 and after deducting a zero position and an acceleration overload term_x', number NW of pulses calculated in unit time of gyro yaw channel of flexible strapdown inertial unit system 1 after zero position and acceleration overload terms are deducted_y', number NW of pulses calculated in unit time of gyroscope pitching channel of flexible strapdown inertial unit system 1 after zero position and acceleration overload item are deducted_z′：

In the above equation 3, NW_xThe number of pulses, NW, in unit time of a gyro rolling channel of the flexible strapdown inertial system 1 is calculated by a computer in the flexible strapdown inertial system 1 at present_yThe number of pulses NW in the unit time of the gyro yaw channel of the flexible strapdown inertial system 1 is calculated by a computer in the flexible strapdown inertial system 1_zCalculating the number of pulses in a unit time of a gyroscope pitching channel of the flexible strapdown inertial system 1 obtained by a computer in the flexible strapdown inertial system 1; e_1xThe flexible strapdown inertial unit system is obtained by calibrating the flexible strapdown inertial unit system 1 by the inertial measurement combination testing equipment 2Scale factor of gyro scroll channel output (number of pulses per unit time subject to unit angular velocity output), E of 1_1yScaling factor, E, for the gyroscope yaw channel output of a flexible strapdown inertial system 1 obtained by calibrating the flexible strapdown inertial system 1 by an inertial measurement unit testing device 2_1zThe calibration factor is the scale factor output by the gyroscope pitching channel of the flexible strapdown inertial unit system 1, which is obtained by calibrating the flexible strapdown inertial unit system 1 by the inertial measurement combination test equipment 2; d_0xZero pulse output for a gyro rolling channel of a flexible strapdown inertial system 1 obtained by calibrating the flexible strapdown inertial system 1 by an inertial measurement combination test equipment 2, D_0yZero pulse output for a gyroscope yaw channel of a flexible strapdown inertial system 1 obtained by calibrating the flexible strapdown inertial system 1 by an inertial measurement combination test device 2, D_0zOutputting zero pulse of a gyroscope pitching channel of the flexible strapdown inertial unit system 1 obtained by calibrating the flexible strapdown inertial unit system 1 by the inertial measurement combined test equipment 2; d_1xThe coefficient of influence of longitudinal acceleration on a gyroscope rolling channel of the flexible strapdown inertial system 1 is obtained by calibrating the flexible strapdown inertial system 1 by the inertial measurement combined test equipment 2, D_1yThe influence coefficient of the longitudinal acceleration on the gyroscope yaw channel of the flexible strapdown inertial system 1, which is obtained by calibrating the flexible strapdown inertial system 1 by the inertial measurement combined test equipment 2, D_1zThe method is characterized in that the method is a gyroscope pitching channel influence coefficient of the flexible strapdown inertial unit system 1 under the longitudinal acceleration, which is obtained by calibrating the flexible strapdown inertial unit system 1 by the inertial measurement combined test equipment 2; d_2xThe influence coefficient of the normal acceleration on the gyro rolling channel of the flexible strapdown inertial system obtained by calibrating the flexible strapdown inertial system 1 by the inertial measurement combined test equipment 2D_2yThe influence coefficient of the normal acceleration on the gyroscope yaw channel of the flexible strapdown inertial system obtained by calibrating the flexible strapdown inertial system 1 by the inertial measurement combined test equipment 2D_2zThe method is characterized in that the method is a gyroscope pitching channel affected normal acceleration coefficient of the flexible strapdown inertial unit system, which is obtained by calibrating the flexible strapdown inertial unit system 1 by the inertial measurement combined test equipment 2; d_3xFor combined testing by inertia testThe equipment 2 calibrates the flexible strapdown inertial unit system 1 to obtain the influence coefficient of the transverse acceleration on the gyro rolling channel of the flexible strapdown inertial unit system 1, D_3yThe influence coefficient of the lateral acceleration on the gyroscope yaw channel of the flexible strapdown inertial system 1 is obtained by calibrating the flexible strapdown inertial system 1 by the inertial measurement combined test equipment 2, D_3zThe method is characterized in that the method is a gyroscope pitching channel affected coefficient of the flexible strapdown inertial unit system 1, wherein the gyroscope pitching channel affected by the transverse acceleration is obtained by calibrating the flexible strapdown inertial unit system 1 through the inertial measurement combined test equipment 2;

and step 3: in the flexible strapdown inertial unit system 1, the pulse number NW within the unit time of the gyroscope rolling channel of the flexible strapdown inertial unit system 1 obtained in the step 2 after the zero position and the acceleration overload item are deducted_x', number NW of pulses per unit time of gyro yaw channel of flexible strapdown inertial unit system 1 after deducting zero position and acceleration overload term_y', number NW of pulses per unit time of gyro pitch channel of flexible strapdown inertial unit system 1 after deducting zero position and acceleration overload term_zRespectively carrying out the existing nonlinear compensation to obtain the pulse number NW output in unit time of the rolling channel of the gyroscope after the nonlinear compensation and deduction of zero position and acceleration overload terms_xThe number NW of pulses output by the gyroscope yaw channel in unit time after nonlinear compensation and zero position and acceleration overload term deduction_yThe number NW of pulses output by the gyroscope pitch channel in unit time after nonlinear compensation and zero position and acceleration overload term deduction_z″；

And 4, step 4: NW obtained according to step 3 in a flexible strapdown inertial unit system 1_x″、NW_y"and NW_z"the compensated number of pulses NW of the gyro rolling channel sensing output of the flexible strapdown inertial unit system 1 is obtained by using the following formula 4_bxThe compensated gyroscope yaw channel induction output pulse number NW of the flexible strapdown inertial unit system 1_byThe compensated gyroscope pitching channel induction output pulse number NW of the flexible strapdown inertial unit system 1_bz:

Wherein E is_1xScaling factor, E, of a gyro-roll channel output of a flexible strapdown inertial system 1 obtained by calibrating the flexible strapdown inertial system 1 by an inertial measurement unit testing device 2_1yScaling factor, E, for the gyroscope yaw channel output of a flexible strapdown inertial system 1 obtained by calibrating the flexible strapdown inertial system 1 by an inertial measurement unit testing device 2_1zThe calibration factor is the scale factor output by the gyroscope pitching channel of the flexible strapdown inertial unit system 1, which is obtained by calibrating the flexible strapdown inertial unit system 1 by the inertial measurement combination test equipment 2; d_0xZero pulse output for a gyro rolling channel of a flexible strapdown inertial system 1 obtained by calibrating the flexible strapdown inertial system 1 by an inertial measurement combination test equipment 2, D_0yZero pulse output for a gyroscope yaw channel of a flexible strapdown inertial system 1 obtained by calibrating the flexible strapdown inertial system 1 by an inertial measurement combination test device 2, D_0zOutputting zero pulse of a gyroscope pitching channel of the flexible strapdown inertial unit system 1 obtained by calibrating the flexible strapdown inertial unit system 1 by the inertial measurement combined test equipment 2; d_1xThe coefficient of influence of longitudinal acceleration on a gyroscope rolling channel of the flexible strapdown inertial system 1 is obtained by calibrating the flexible strapdown inertial system 1 by the inertial measurement combined test equipment 2, D_1yThe influence coefficient of the longitudinal acceleration on the gyroscope yaw channel of the flexible strapdown inertial system 1, which is obtained by calibrating the flexible strapdown inertial system 1 by the inertial measurement combined test equipment 2, D_1zThe method is characterized in that the method is a gyroscope pitching channel influence coefficient of the flexible strapdown inertial unit system 1 under the longitudinal acceleration, which is obtained by calibrating the flexible strapdown inertial unit system 1 by the inertial measurement combined test equipment 2; d_2xThe influence coefficient of the normal acceleration on the gyro rolling channel of the flexible strapdown inertial system obtained by calibrating the flexible strapdown inertial system 1 by the inertial measurement combined test equipment 2D_2yThe gyroscope of the flexible strapdown inertial system is obtained by calibrating the flexible strapdown inertial system 1 by the inertial measurement combination testing equipment 2Coefficient of influence of normal acceleration on yaw channel, D_2zThe method is characterized in that the method is a gyroscope pitching channel affected normal acceleration coefficient of the flexible strapdown inertial unit system, which is obtained by calibrating the flexible strapdown inertial unit system 1 by the inertial measurement combined test equipment 2; d_3xThe coefficient of influence of the transverse acceleration on the gyro rolling channel of the flexible strapdown inertial system 1 is obtained by calibrating the flexible strapdown inertial system 1 by the inertial measurement combination testing equipment 2D_3yThe influence coefficient of the lateral acceleration on the gyroscope yaw channel of the flexible strapdown inertial system 1 is obtained by calibrating the flexible strapdown inertial system 1 by the inertial measurement combined test equipment 2, D_3zThe method is characterized in that the method is a gyroscope pitching channel affected coefficient of the flexible strapdown inertial unit system 1, wherein the gyroscope pitching channel affected by the transverse acceleration is obtained by calibrating the flexible strapdown inertial unit system 1 through the inertial measurement combined test equipment 2; ax is a longitudinal acceleration of a moving object on which the flexible strapdown inertial unit system 1 is mounted, Ay is a normal acceleration of the moving object on which the flexible strapdown inertial unit system 1 is mounted, and Az is a lateral acceleration of the moving object on which the flexible strapdown inertial unit system 1 is mounted.

The existing nonlinear compensation method in step 3 of the above technical solution is an adaptive compensation method (for details, see how kunpeng, et al, written "dynamic tuning gyro scale factor nonlinear error compensation research"), or a second-order nonlinear compensation method.

In the above technical solution, the flexible strapdown inertial measurement unit system 1 and the inertial measurement unit testing device 2 are both conventional devices.

In order to verify the compensation effect in the high dynamic navigation test, the same set of flexible strapdown inertial unit system 1 is subjected to relevant tests. The same road section is selected in the test, and the speeds of the two roadsters are kept consistent as much as possible. The table 1 is the navigation deviation data obtained by carrying out the sports car test after the acceleration overload item is compensated and the nonlinear compensation is not deducted, and the table 2 is the navigation deviation data obtained by carrying out the sports car test after the acceleration overload item is deducted and the nonlinear compensation. The test deviations refer to pure inertial navigation and GPS position deviations.

TABLE 1 sports results without compensation for acceleration overload term deduction

Time(s)	Warp deviation (m)	Latitudinal deviation (m)	Radial deflection (m)
				100	0	0	0
200	-287.556	111.3195	308.3511
				300	-862.668	111.3195	869.8204
400	-1246.05	556.5974	1364.713
				500	-1437.66	556.5974	1541.645

TABLE 2 sports results compensated for acceleration overload term deduction

Comparing table 1 and table 2, it can be known that the navigation accuracy of the flexible strapdown inertial measurement unit after the acceleration overload term is deducted and the nonlinear compensation is performed is greatly improved.

Details not described in this specification are within the skill of the art that are well known to those skilled in the art.

Claims (2)

1. A gyro scale factor online compensation method based on a flexible strapdown inertial system model is characterized by comprising the following steps:

step 1: a computer in the flexible strapdown inertial unit system (1) calculates and obtains the longitudinal pulse number NA of the currently output flexible strapdown inertial unit system (1) in a preset unit time_x', normal pulse number NA_y' sum number of transverse pulses NA_Z' obtaining a longitudinal acceleration Ax, a normal acceleration Ay and a transverse acceleration Az of a moving object carrying the flexible strapdown inertial unit system (1) by using the following formula 1;

$\left.\begin{array}{c}Ax=\left(\right(1-K_{y^{\′}z}\×K_{z^{\′}y})\×m-(K_{y^{\′}x}-K_{z^{\′}x}\×K_{y^{\′}z})\×n-(K_{z^{\′}x}-K_{y^{\′}x}\×K_{z^{\′}y})\×r)/vv\\ Ay=\left(\right(1-K_{x^{\′}z}\×K_{z^{\′}x})\×n-(K_{x^{\′}y}-K_{z^{\′}y}\×K_{x^{\′}z})\×m-(K_{z^{\′}y}-K_{x^{\′}y}\×K_{z^{\′}x})\×r)/vv\\ Az=\left(\right(1-K_{x^{\′}y}\×K_{y^{\′}x})\×r-(K_{x^{\′}z}-K_{x^{\′}y}\×K_{y^{\′}z})\×m-(K_{y^{\′}z}-K_{y^{\′}x}\×K_{x^{\′}z})\×n)/vv\end{array}\right\}---1)$

wherein,

$\left.\begin{array}{c}m={\mathrm{NA}}_x^{\′}/(K_{1x}\×\mathrm{\τ})-K_{0x}\\ n={\mathrm{NA}}_y^{\′}/(K_{1y}\×\mathrm{\τ})-K_{0y}\\ r={\mathrm{NA}}_z^{\′}/(K_{1z}\×\mathrm{\τ})-K_{0z}\\ vv=1-K_{z^{\′}y}\×K_{z^{\′}x}-K_{y^{\′}z}\×K_{y^{\′}x}-K_{x^{\′}z}\×K_{x^{\′}y}\end{array}\right\}---2)$

k in the above-mentioned formula 1 and formula 2_1x、K_1y、K_1zThe calibration factors output by a longitudinal accelerometer, a normal accelerometer and a transverse accelerometer in the flexible strapdown inertial unit system (1) are respectively obtained by calibrating the flexible strapdown inertial unit system (1) by the inertial measurement combined test equipment (2); k_y′x、K_z′x、K_x′y、K_z′y、K_x′z、K_y′zThe method is characterized in that the installation error coefficient of the accelerometer of the flexible strapdown inertial unit system (1) is obtained by calibrating the flexible strapdown inertial unit system (1) by the inertial measurement combination test equipment (2), wherein K_y′xIs a vertical installation error coefficient, K, of a longitudinal accelerometer in a flexible strapdown inertial unit system (1) relative to a normal axis y' of a flexible strapdown inertial unit body_z′xIs a vertical installation error coefficient, K, of a longitudinal accelerometer in a flexible strapdown inertial unit system (1) relative to a transverse axis z' of a flexible strapdown inertial unit body_x′yIs a vertical installation error coefficient, K, of a normal accelerometer in a flexible strapdown inertial unit system (1) relative to a longitudinal axis x' of a flexible strapdown inertial unit body_z′yIs a vertical installation error coefficient, K, of a normal accelerometer in a flexible strapdown inertial unit system (1) relative to a transverse axis z' of a flexible strapdown inertial unit body_x′zIs a vertical installation error coefficient, K, of a transverse accelerometer in a flexible strapdown inertial unit system (1) relative to a longitudinal axis x' of a flexible strapdown inertial unit body_y′zIs a vertical installation error coefficient, K, of a transverse accelerometer in a flexible strapdown inertial unit system (1) relative to a normal axis y' of a flexible strapdown inertial unit body_0x、K_0y、K_0zZero-order errors of a longitudinal accelerometer, a normal accelerometer and a transverse accelerometer in the flexible strapdown inertial system (1) are respectively obtained by calibrating the flexible strapdown inertial system (1) by the inertial measurement combined test equipment (2);

the longitudinal pulse number NA of the flexible strapdown inertial unit system (1)_x', normal pulse number NA_y' sum number of transverse pulses NA_ZThe method comprises the steps that the number of acceleration output pulses in the current unit time is obtained through calculation by a computer in the flexible strapdown inertial unit system (1);

step 2: obtaining the pulse number NW calculated in the flexible strapdown inertial unit system (1) in unit time by using the following formula 3 according to the longitudinal acceleration Ax, the normal acceleration Ay and the transverse acceleration Az of a moving object carrying the flexible strapdown inertial unit system (1) and after deducting zero position and acceleration overload terms_x', flexible strapdown inertial unit system (1) with zero and acceleration overload terms subtractedPulse number NW obtained by calculation in unit time of gyroscope yaw channel_y', pulse number NW calculated in unit time of gyroscope pitching channel of flexible strapdown inertial unit system (1) after zero position and acceleration overload item are deducted_z′：

$\left.\begin{array}{c}{{\mathrm{NW}}_x}^{\′}={\mathrm{NW}}_x-E_{1x}\×(D_{0x}+D_{1x}\×Ax+D_{2x}\×Ay+D_{3x}\×Az)\\ {{\mathrm{NW}}_y}^{\′}={\mathrm{NW}}_y-E_{1y}\×(D_{0y}+D_{1y}\×Ax+D_{2y}\×Ay+D_{3y}\×Az)\\ {{\mathrm{NW}}_z}^{\′}={\mathrm{NW}}_z-E_{1z}\×(D_{0z}+D_{1z}\×Ax+D_{2z}\×Ay+D_{3z}\×Az)\end{array}\right\}---3)$

In the above equation 3, NW_xFor the present flexibilityThe number of pulses in the unit time of a gyroscope rolling channel of the flexible strapdown inertial system (1) obtained by the computer in the inertial system (1) is NW_yThe number of pulses NW in the unit time of the gyroscope yaw channel of the flexible strapdown inertial system (1) is obtained by the computer in the flexible strapdown inertial system (1)_zCalculating the number of pulses in a unit time of a gyroscope pitching channel of the flexible strapdown inertial system (1) obtained by a computer in the flexible strapdown inertial system (1); e_1xScale factors of the gyro rolling channel output of the flexible strapdown inertial unit system (1) obtained by calibrating the flexible strapdown inertial unit system (1) by the inertial measurement combination test equipment (2), E_1yScale factors of the gyroscope yaw channel output of the flexible strapdown inertial unit system (1) obtained by calibrating the flexible strapdown inertial unit system (1) by the inertial measurement combined test equipment (2), E_1zThe calibration factor is the scale factor output by a gyroscope pitching channel of the flexible strapdown inertial unit system (1) obtained by calibrating the flexible strapdown inertial unit system (1) by the inertial measurement combined test equipment (2); d_0xZero pulse output of a gyroscope rolling channel of the flexible strapdown inertial unit system (1) is obtained by calibrating the flexible strapdown inertial unit system (1) by the inertial measurement combined test equipment (2), D_0yZero pulse output of a gyroscope yaw channel of the flexible strapdown inertial unit system (1) is obtained by calibrating the flexible strapdown inertial unit system (1) through the inertial measurement combination testing equipment (2), D_0zZero pulse output of a gyroscope pitching channel of the flexible strapdown inertial unit system (1) is obtained by calibrating the flexible strapdown inertial unit system (1) through the inertial measurement combined test equipment (2); d_1xThe influence coefficient of longitudinal acceleration on a gyroscope rolling channel of the flexible strapdown inertial unit system (1) is obtained by calibrating the flexible strapdown inertial unit system (1) by the inertial measurement combined test equipment (2), D_1yThe influence coefficient of the longitudinal acceleration on the gyroscope yaw channel of the flexible strapdown inertial unit system (1) obtained by calibrating the flexible strapdown inertial unit system (1) by the inertial measurement combined test equipment (2), D_1zThe method is characterized in that the method is a gyroscope pitching channel influence coefficient of the flexible strapdown inertial unit system (1) under the longitudinal acceleration, which is obtained by calibrating the flexible strapdown inertial unit system (1) by the inertial measurement combined test equipment (2); d_2xThe influence coefficient of normal acceleration on a gyroscope rolling channel of the flexible strapdown inertial unit system obtained by calibrating the flexible strapdown inertial unit system (1) by the inertial measurement combined test equipment (2), D_2yThe influence coefficient of the normal acceleration on the gyroscope yaw channel of the flexible strapdown inertial unit system obtained by calibrating the flexible strapdown inertial unit system (1) by the inertial measurement combined test equipment (2), D_2zThe method is characterized in that the method is a gyroscope pitching channel normal acceleration influence coefficient of the flexible strapdown inertial unit system obtained by calibrating the flexible strapdown inertial unit system (1) by the inertial measurement combined test equipment (2); d_3xThe coefficient of influence of transverse acceleration on a gyroscope rolling channel of the flexible strapdown inertial unit system (1) is obtained by calibrating the flexible strapdown inertial unit system (1) by the inertial measurement combined test equipment (2), D_3yThe influence coefficient of the transverse acceleration on the gyroscope yaw channel of the flexible strapdown inertial unit system (1) obtained by calibrating the flexible strapdown inertial unit system (1) by the inertial measurement combined test equipment (2), D_3zThe method is characterized in that the method is a gyroscope pitching channel influence coefficient of the flexible strapdown inertial unit system (1) obtained by calibrating the flexible strapdown inertial unit system (1) by the inertial measurement combined test equipment (2);

and step 3: in the flexible strapdown inertial unit system (1), the pulse number NW within unit time of the gyroscope rolling channel of the flexible strapdown inertial unit system (1) obtained in the step 2 after zero position and acceleration overload terms are deducted_x', number NW of pulses in unit time of gyro yaw channel of flexible strapdown inertial unit system (1) after deducting zero position and acceleration overload term_y', number NW of pulses in unit time of gyro pitching channel of flexible strapdown inertial unit system (1) after deducting zero position and acceleration overload term_zRespectively carrying out the existing nonlinear compensation to obtain the pulse number NW output in unit time of the rolling channel of the gyroscope after the nonlinear compensation and deduction of zero position and acceleration overload terms_xThe number NW of pulses output by the gyroscope yaw channel in unit time after nonlinear compensation and zero position and acceleration overload term deduction_yThe number NW of pulses output by the gyroscope pitch channel in unit time after nonlinear compensation and zero position and acceleration overload term deduction_z″；

And 4, step 4: in a flexible strapdown inertial unit system (1) according to the NW obtained in step 3_x″、NW_y"and NW_z"obtaining compensated gyro rolling channel induction output pulse number NW of flexible strapdown inertial unit system (1) by following formula 4_bxThe compensated gyroscope yaw channel induction output pulse number NW of the flexible strapdown inertial unit system (1)_byThe compensated gyroscope pitching channel induction output pulse number NW of the flexible strapdown inertial unit system (1)_bz:

$\left.\begin{array}{c}{\mathrm{NW}}_{bx}=E_{1x}\×(D_{0x}+D_{1x}\×Ax+D_{2x}\×Ay+D_{3x}\×Az)+{{\mathrm{NW}}_x}^{\′\′}\\ {\mathrm{NW}}_{by}=E_{1y}\×(D_{0y}+D_{1y}\×Ax+D_{2y}\×Ay+D_{3y}\×Az)+{{\mathrm{NW}}_y}^{\′\′}\\ {\mathrm{NW}}_{bz}=E_{1z}\×(D_{0z}+D_{1z}\×Ax+D_{2z}\×Ay+D_{3z}\×Az)+{{\mathrm{NW}}_z}^{\′\′}\end{array}\right\}---4)$

Wherein E is_1xScale factors of the gyro rolling channel output of the flexible strapdown inertial unit system (1) obtained by calibrating the flexible strapdown inertial unit system (1) by the inertial measurement combination test equipment (2), E_1yScale factors of the gyroscope yaw channel output of the flexible strapdown inertial unit system (1) obtained by calibrating the flexible strapdown inertial unit system (1) by the inertial measurement combined test equipment (2), E_1zThe calibration factor is the scale factor output by a gyroscope pitching channel of the flexible strapdown inertial unit system (1) obtained by calibrating the flexible strapdown inertial unit system (1) by the inertial measurement combined test equipment (2); d_0xZero pulse output of a gyroscope rolling channel of the flexible strapdown inertial unit system (1) is obtained by calibrating the flexible strapdown inertial unit system (1) by the inertial measurement combined test equipment (2), D_0yZero pulse output of a gyroscope yaw channel of the flexible strapdown inertial unit system (1) is obtained by calibrating the flexible strapdown inertial unit system (1) through the inertial measurement combination testing equipment (2), D_0zZero pulse output of a gyroscope pitching channel of the flexible strapdown inertial unit system (1) is obtained by calibrating the flexible strapdown inertial unit system (1) through the inertial measurement combined test equipment (2); d_1xThe influence coefficient of longitudinal acceleration on a gyroscope rolling channel of the flexible strapdown inertial unit system (1) is obtained by calibrating the flexible strapdown inertial unit system (1) by the inertial measurement combined test equipment (2), D_1yThe flexible strapdown inertial unit system (1) is calibrated by the inertial measurement combination testing equipment (2)Coefficient of influence of longitudinal acceleration on the gyro yaw path of the inertial unit system (1), D_1zThe method is characterized in that the method is a gyroscope pitching channel influence coefficient of the flexible strapdown inertial unit system (1) under the longitudinal acceleration, which is obtained by calibrating the flexible strapdown inertial unit system (1) by the inertial measurement combined test equipment (2); d_2xThe influence coefficient of normal acceleration on a gyroscope rolling channel of the flexible strapdown inertial unit system obtained by calibrating the flexible strapdown inertial unit system (1) by the inertial measurement combined test equipment (2), D_2yThe influence coefficient of the normal acceleration on the gyroscope yaw channel of the flexible strapdown inertial unit system obtained by calibrating the flexible strapdown inertial unit system (1) by the inertial measurement combined test equipment (2), D_2zThe method is characterized in that the method is a gyroscope pitching channel normal acceleration influence coefficient of the flexible strapdown inertial unit system obtained by calibrating the flexible strapdown inertial unit system (1) by the inertial measurement combined test equipment (2); d_3xThe coefficient of influence of transverse acceleration on a gyroscope rolling channel of the flexible strapdown inertial unit system (1) is obtained by calibrating the flexible strapdown inertial unit system (1) by the inertial measurement combined test equipment (2), D_3yThe influence coefficient of the transverse acceleration on the gyroscope yaw channel of the flexible strapdown inertial unit system (1) obtained by calibrating the flexible strapdown inertial unit system (1) by the inertial measurement combined test equipment (2), D_3zThe method is characterized in that the method is a gyroscope pitching channel influence coefficient of the flexible strapdown inertial unit system (1) obtained by calibrating the flexible strapdown inertial unit system (1) by the inertial measurement combined test equipment (2); ax is the longitudinal acceleration of a moving object carrying the flexible strapdown inertial unit system (1), Ay is the normal acceleration of the moving object carrying the flexible strapdown inertial unit system (1), and Az is the lateral acceleration of the moving object carrying the flexible strapdown inertial unit system (1).

2. The flexible strapdown inertial system model-based gyro scale factor online compensation method of claim 1, wherein: the existing nonlinear compensation method in the step 3 is a self-adaptive compensation method or a second-order nonlinear compensation method.