Non-singular fast transfer alignment method for any misalignment angle of precise aerial navigation inertial device

Abstract

The application discloses a fast transfer alignment method without singularity for any misalignment angle of precise air-drop inertial navigation device, which comprises the following steps: after the alignment starts, the on-board main inertial navigation device and the precise air-drop inertial navigation device respectively perform attitude updating in the inertial system, and real-time solve the attitude matrix and the inertial navigation sampling period; based on the angular velocity and the specific force measurement of the on-board main inertial navigation device and the precise air-drop inertial navigation device, a matching model of the angular velocity integral and the specific force integral in the inertial system is established; a Kalman filtering state equation is established, and the Kalman filtering time updating is completed; according to the obtained integral quantity, the state equation is combined to construct a measurement equation; the Kalman filtering measurement updating is completed; the attitude tracking error compensation of the precise air-drop inertial navigation device in the inertial system is completed; and the attitude matrix at the alignment end moment of the precise air-drop inertial navigation device is obtained. The method can quickly complete the transfer alignment under the simple circling maneuver of the carrier.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of precise air-drop control equipment with inertial navigation device, and relates to a fast transfer alignment method without singularity for any misalignment angle of a precise air-drop inertial navigation device. BACKGROUND

[0002] The air-drop system is a technology for delivering personnel and materials to a designated place by using parachutes. The traditional air-drop system is affected by the precision of navigation and guidance, and the air-dropped materials are generally scattered everywhere like "flower scattering by a fairy". The precise air-drop system combines modern navigation (especially inertial navigation technology), guidance and control technology with traditional air-drop technology, and can realize air-drop flight path planning, wing parachute control, atmospheric estimation, long-distance precise delivery and other functions, greatly expanding the practical application of air-drop. It can be said that whether having an inertial navigation device, a satellite navigation system and a radio navigation device is the main sign of distinguishing modern precise air-drop from traditional air-drop, and is also the mainstream direction of air-drop development.

[0003] The inertial navigation is a real-time navigation means of dead reckoning, and has complete autonomy and natural combination advantage with the satellite navigation system. However, the inertial navigation device needs to determine its initial attitude information, i.e. initial alignment, before entering the navigation working state. The length of the alignment time represents the fast reaction ability of the inertial navigation system.

[0004] Due to the particularity of the precise air-drop system, it is required to complete the initial attitude determination in a short time, to meet the requirements of the actual air-drop carrier platform, and not to limit the installation mode of the air-drop inertial navigation device. Therefore, a simple and easy method is needed, which can adapt to the air-drop carrier maneuvering condition, and can quickly determine the initial attitude with any misalignment angle without singularity.

[0005] In the traditional transfer alignment, according to the size of the misalignment angle, it is mainly divided into a linear model of small misalignment angle and a nonlinear model of large misalignment angle. The installation relationship of the master and the slave inertial navigation device needs to be confirmed in advance. For the case of large misalignment angle, the nonlinear filter needs to be used, and therefore there are problems of large calculation amount and low estimation precision. SUMMARY

[0006] The purpose of the present application is to provide a fast transfer alignment method without singularity for any misalignment angle of a precise air-drop inertial navigation device, which can quickly complete the transfer alignment under the simple circling maneuver of the carrier.

[0007] The technical solution adopted by the present application is that the fast transfer alignment method without singularity for any misalignment angle of a precise air-drop inertial navigation device is implemented according to the following steps.

[0008] Step 1, establishing a quasi-inertial coordinate system at the initial alignment starting time;

[0009] Step 2: After the alignment begins, the onboard main inertial navigation system and the precision airdrop inertial navigation system respectively update the attitude in the inertial system and solve the attitude matrix in real time. and

[0010] Step 3: During the inertial navigation sampling period, based on the angular velocity and specific force measurements of the airborne main inertial navigation system and the precision airdrop inertial navigation system, a matching model of the angular velocity integral and the specific force integral in the inertial system is established;

[0011] Step 4: Establish the Kalman filter state equation and complete the Kalman filter time update;

[0012] Step 5: Based on the integral obtained in step 3 and the state equation, the measurement equation is constructed;

[0013] Step 6: Complete Kalman filter measurement update;

[0014] Step 7: Complete the compensation of the attitude tracking error in the inertial system of the precise airdrop inertial navigation device; obtain the attitude matrix of the precise airdrop inertial navigation device at the end of alignment.

[0015] The present invention is also characterized in that:

[0016] In step 2, the attitude differential equation under the airborne main inertial navigation inertial system is:

[0017]

[0018] in, Indicates the output angular velocity of the onboard main inertial navigation gyro The cross product antisymmetric matrix, Represents the coordinate system m of the airborne main inertial navigation carrier to the carrier inertial system i m The attitude transformation matrix, I3 represents the third-order identity matrix;

[0019] The attitude differential equation of the precision airdrop inertial navigation unit in the inertial system is:

[0020]

[0021] in, Indicates the gyro output angular velocity of the precision airdrop inertial navigation device The cross product antisymmetric matrix of ; Represents the coordinate system s of the airborne main inertial navigation carrier to the carrier inertial system i s The posture transformation matrix.

[0022] In step 3, the angular velocity measurement relationship is:

[0023]

[0024] Where, is the attitude transformation matrix from the airborne master INS body frame s to the body inertial frame i s ; is the gyro output angular rate of the precision aerial delivery INS; is the error in the angular rate measurement of the precision aerial delivery INS projected in the i s frame; is the fixed mounting attitude matrix between the airborne master INS and the precision aerial delivery INS; is the attitude transformation matrix from the airborne master INS body frame m to the body inertial frame i m ; is the gyro output angular rate of the airborne master INS; is the angular rate of the precision aerial delivery INS relative to the airborne master INS due to elastic deformation; is the elastic deformation residual term, considered as noise;

[0025] The ratio force measurement relationship is:

[0026]

[0027] where, is the projection of the precision aerial delivery INS ratio force measurement in the i s frame; is the error in the ratio force measurement of the precision aerial delivery INS projected in the i s frame; is the projection of the compensated ratio force measurement of the airborne master INS in the i m frame; is the boom compensation residual term, considered as noise.

[0028] Integrating the two equations representing the angular rate measurement, ratio force measurement relationship, the integration of the is calculated as:

[0029] The precision aerial delivery INS angular rate integration:

[0030]

[0031] The airborne master INS angular rate integration:

[0032]

[0033] The precision aerial delivery INS ratio force integration:

[0034]

[0035] The airborne master INS ratio force integration:

[0036]

[0037] Step 4, select the fixed installation attitude matrix between the airborne master inertial navigation and the accurate air-drop inertial navigation device vectorization element of angular velocity integral error specific force integral error inertial system attitude error of the carrier of the accurate air-drop inertial navigation device gyro drift ε of the accurate air-drop inertial navigation device s accelerometer zero offset of the accurate air-drop inertial navigation device As a state, the obtained Kalman filtering state equation is:

[0038]

[0039] wherein,

[0040]

[0041] that is,

[0042] The system matrix A is The state transition matrix B is The process noise vector W is wherein, represents the projection of the specific force measurement of the accurate air-drop inertial navigation device in the i s inertial system; represents the attitude transformation matrix of the carrier coordinate system s of the airborne master inertial navigation to the inertial system i s of the carrier; is the gyro measurement noise of the accurate air-drop inertial navigation device; w a s is the measurement noise of the accelerometer of the accurate air-drop inertial navigation device; represents the projection of the angular velocity measurement of the accurate air-drop inertial navigation device in the i s inertial system.

[0043] The measurement equation constructed in Step 5 is:

[0044]

[0045] In the above formula,

[0046]

[0047] In the above formula, I3 represents a three-order unit matrix; 0 n×m represents an n×m-dimensional zero matrix.

[0048]

[0049] are the specific force and angular velocity integral quantities of the accurate air-drop inertial navigation device, respectively; The specific gravity, the angular velocity integral component of the airborne main inertial navigation respectively.

[0050] Step 7 is specifically:

[0051] It is judged whether the transfer alignment time is over, if not, it returns to step 2 to continue to execute; if yes, the compensation of the attitude tracking result of the inertial system of the accurate air-drop inertial navigation device is completed, the attitude updating result of the accurate air-drop inertial navigation device and the carrier coordinate system of the airborne main inertial navigation is obtained in combination with the result of step 2, and the current attitude matrix of the accurate air-drop inertial navigation device is obtained , that is, the transfer alignment process is completed.

[0052] In step 7, the current attitude matrix of the accurate air-drop inertial navigation device is:

[0053]

[0054] In the formula, is the attitude matrix of the airborne main inertial navigation at the alignment end time; is the attitude tracking result of the airborne main inertial navigation in the inertial system; is the attitude tracking result of the accurate air-drop inertial navigation device in the inertial system; is the fixed installation attitude matrix between the airborne main inertial navigation and the accurate air-drop inertial navigation device.

[0055] The beneficial effects of the present application are:

[0056] (1) The fixed installation attitude matrix between the airborne main inertial navigation and the accurate air-drop inertial navigation device is taken as the filter state in the method, the transfer alignment filter model established is the unified linearization alignment model under arbitrary misalignment angle, and the problems of the nonlinear filter and singular point in the traditional technology are avoided;

[0057] (2) The alignment model taking the angular velocity integral and the specific gravity integral as the measurement is established, and the rapid alignment of the accurate air-drop inertial navigation device can be realized;

[0058] (3) The method has no special requirement for the installation of the accurate air-drop inertial navigation device, can rapidly complete the initial alignment under the simple circling maneuver of the carrier, and improves the combat effectiveness and air-drop precision of the equipment. BRIEF DESCRIPTION OF DRAWINGS

[0059] Figure 1 is the flow chart of the method;

[0060] Figure 2 is the small-angle installation error angle estimation result graph under the circling maneuver of the carrier in the embodiment of the present application;

[0061] Figure 3 ​is the large-angle installation error angle estimation result figure of the carrier in the hovering maneuver in the embodiment of the application. DETAILED DESCRIPTION

[0062] The application will be described in detail below with reference to the drawings and specific embodiments.

[0063] The arbitrary misalignment angle singularity-free fast transfer alignment method of the accurate air-drop inertial navigation device uses the output information of the airborne main inertial navigation device, and can complete the transfer alignment of the accurate air-drop inertial navigation device under the condition of hovering maneuver. The flow is shown in Figure 1 The method is implemented according to the following steps.

[0064] Step 1: Establish the quasi-inertial coordinate system at the initial alignment start time.

[0065] Step 2: After the alignment starts, the carrier coordinate systems of the airborne main inertial navigation device and the accurate air-drop inertial navigation device are updated in the respective carrier inertial systems, and the attitude matrices and are calculated in real time.

[0066] The attitude differential equation in the inertial system of the airborne main inertial navigation device is:

[0067]

[0068] wherein, represents the cross product anti-symmetric matrix of the gyro output angular velocity of the airborne main inertial navigation device, represents the attitude transformation matrix of the airborne main inertial navigation device carrier coordinate system m to the carrier inertial system i m , and I3 represents a three-order unit matrix.

[0069] The attitude differential equation in the inertial system of the accurate air-drop inertial navigation device is:

[0070]

[0071] wherein, represents the cross product anti-symmetric matrix of the gyro output angular velocity of the accurate air-drop inertial navigation device; represents the attitude transformation matrix of the airborne main inertial navigation device carrier coordinate system s to the carrier inertial system i s .

[0072] Step 3: Based on the angular velocity and specific force measurements of the airborne main inertial navigation device and the accurate air-drop inertial navigation device, the matching model of the angular velocity integral and the specific force integral in the inertial system is established at the inertial sampling period. The angular velocity measurement relationship is:

[0073]

[0074] In the formula, is the projection of the precision aerial dropped INS angular rate measurement in the i s frame; is the fixed mounting attitude matrix between the airborne master INS and the precision aerial dropped INS; is the precision aerial dropped INS angular rate relative to the airborne master INS, resulting from elastic deformation; is the elastic deformation residual term, considered as noise.

[0075] The specific force measurement relationship is:

[0076]

[0077] where, is the projection of the precision aerial dropped INS specific force measurement in the i s frame; is the projection of the precision aerial dropped INS specific force measurement in the i s frame; is the projection of the compensated airborne master INS specific force measurement in the i m frame; is the arm compensation residual term, considered as noise.

[0078] Integrate equations (3) and (4), and calculate the integral quantities to obtain:

[0079] Integrate the precision aerial dropped INS angular rate:

[0080]

[0081] Integrate the airborne master INS angular rate:

[0082]

[0083] Integrate the precision aerial dropped INS specific force:

[0084]

[0085] Integrate the airborne master INS specific force:

[0086]

[0087] Step 4: Establish the Kalman filter state equation, and complete the Kalman filter time update according to the state equation.

[0088] Select the vectorized elements of the fixed mounting attitude matrix between the airborne master INS and the precision aerial dropped INS angular rate integration error specific force integration error Attitude error of precise air-drop inertial navigation device carrier inertial system Gyroscope drift of precise air-drop inertial navigation device s Accelerometer bias of precise air-drop inertial navigation device As state, i.e. Kalman filter state is:

[0089]

[0090] Wherein, vec(·) represents connecting the matrix at the beginning and end of the row to form a column vector.

[0091] i s The attitude error equation defined by misalignment angle under the system is:

[0092]

[0093] In the formula, is the gyroscope measurement noise of the precise air-drop inertial navigation device.

[0094] Angular velocity integral error The differential equation of is:

[0095]

[0096] Specific force integral error The differential equation of is:

[0097]

[0098] In the formula, w a s Random constant bias and measurement noise of the accelerometer of the precise air-drop inertial navigation device are respectively.

[0099] The system state equation is as follows:

[0100]

[0101] Wherein,

[0102]

[0103] That is,

[0104] The system matrix A is The state transition matrix B is The process noise vector W is

[0105] Step 5, according to the integral quantity obtained in step 3 Combined with the Kalman filter state equation in step 4, the measurement equation is constructed.

[0106] The constructed measurement equation is:

[0107]

[0108] In formula (15), I3 represents a third-order unit matrix,

[0109]

[0110] In formula (16), I3 represents a third-order unit matrix,

[0111]

[0112] Step 6: According to the measurement equation in step 5, the Kalman filter measurement update process is completed.

[0113] Step 7: It is judged whether the transfer alignment time is over. If not, it is returned to step 2 to continue to execute. If the transfer alignment time is over, the compensation of the attitude tracking result of the accurate air-drop inertial navigation device in the inertial system is completed , the attitude update result of the accurate air-drop inertial navigation device and the airborne main inertial navigation carrier coordinate system obtained in step 2 is combined, and the current attitude matrix of the accurate air-drop inertial navigation device is obtained, that is, the transfer alignment process is completed.

[0114] The current attitude matrix of the accurate air-drop inertial navigation device is:

[0115]

[0116] In the formula, is the attitude matrix of the airborne main inertial navigation device at the alignment end moment; is the attitude tracking result in the inertial system of the airborne main inertial navigation device; is the attitude tracking result in the inertial system of the accurate air-drop inertial navigation device; is the fixed installation attitude matrix between the airborne main inertial navigation device and the accurate air-drop inertial navigation device.

[0117] Embodiment 1:

[0118] In step 1, the quasi-inertial coordinate system at the initial alignment start moment is established. Specifically, the related coordinate system involved in the transfer alignment process is defined as follows:

[0119] (1) The accurate air-drop inertial navigation device carrier coordinate system (s system)

[0120] is represented by ox s y s z s , the coordinate origin is located at the sensitive center of the IMU of the accurate air-drop inertial navigation device, ox s axis is along the right direction of the attitude lateral axis, oy s axis is along the front direction of the attitude lateral axis; ox s, oy s , oz s constitute a right-handed orthogonal coordinate system.

[0121] (2) Airborne main inertial navigation carrier coordinate system (m system)

[0122] with ox m y m z m , the coordinate origin is located at the sensitive center of the airborne main inertial navigation IMU, ox m axis is along the right of the attitude lateral axis, oy m axis is along the front of the attitude lateral axis; ox m , oy m , oz m constitute a right-handed orthogonal coordinate system.

[0123] (3) Precise air-drop inertial navigation device carrier inertial system (i s system)

[0124] At the initial moment of alignment, the precise air-drop inertial navigation device carrier coordinate system s is artificially "solidified" in inertial space, obtaining the precise air-drop inertial navigation device carrier inertial system i s .

[0125] (4) Airborne main inertial navigation carrier inertial system (i m system)

[0126] At the initial moment of alignment, the airborne main inertial navigation carrier coordinate system m is artificially "solidified" in inertial space, obtaining the airborne main inertial navigation carrier inertial coordinate system i m .

[0127] (5) Navigation coordinate system (n system)

[0128] with ox n y n z n , the navigation coordinate system is selected as the east-north-up geographical coordinate system.

[0129] In step 2, the calculation of attitude matrix and can be determined by the attitude quaternion method.

[0130] In step 3, the integral quantities are calculated according to equations (5) to (8) respectively.

[0131] In step 4, the Kalman filter time update is completed according to the Kalman filter state equation (13).

[0132] In step 5, the system measurement equation is determined by equation (15).

[0133] In step 6 and step 7, the fixed installation attitude matrix between the airborne main inertial navigation system and the accurate air-dropped inertial navigation device is calculated according to the filtering result of the Kalman filter, and the compensation of the attitude tracking result of the accurate air-dropped inertial navigation device in the inertial system is completed, so that the initial attitude matrix (17) of the accurate air-dropped inertial navigation device can be obtained at the end of alignment. In step 6 and step 7, the fixed installation attitude matrix between the airborne main inertial navigation system and the accurate air-dropped inertial navigation device is calculated according to the filtering result of the Kalman filter, and the compensation of the attitude tracking result of the accurate air-dropped inertial navigation device in the inertial system is completed, so that the initial attitude matrix (17) of the accurate air-dropped inertial navigation device can be obtained at the end of alignment.

[0134] Embodiment 2

[0135] Simulation conditions: the total simulation time is 10s, the inclination angle of the carrier is 15°, the radius of the turn is 1000m, the turn speed is 180m / s, the gyro drift error of the accurate air-dropped inertial navigation device is 1° / h, the random walk noise is The accelerometer zero is 200ug, the random noise is The inertial navigation sampling period is 10ms.

[0136] The fixed installation attitude relationship between the airborne main inertial navigation system and the accurate air-dropped inertial navigation device is set in the Euler angle mode, which is divided into two cases of small attitude angle and large attitude angle.

[0137] The small attitude angle is set as: the pitch angle is 1°, the roll angle is 2°, and the azimuth angle is 3°.

[0138] The large attitude angle is set as: the pitch angle is 30°, the roll angle is 50°, and the azimuth angle is 60°.

[0139] Figure 2 and Figure 3 respectively, are the estimation results of the small-angle and large-angle installation error angles, and it can be seen that under the carrier turn maneuvering condition, no matter the size of the installation error angle, the method can correctly estimate within 10s, that is, quickly complete the high-precision alignment.

[0140] Embodiment 3

[0141] The arbitrary misalignment angle of the accurate air-dropped inertial navigation device is not singularly and quickly transferred, and is implemented according to the following steps:

[0142] Step 1, an initial inertial coordinate system at the initial alignment start time is established;

[0143] Step 2, after the alignment starts, the airborne main inertial navigation system and the accurate air-dropped inertial navigation device respectively perform attitude updating in the inertial system, and real-time solve the attitude matrices and

[0144] Step 3, in the inertial navigation sampling period, based on the angular velocity and specific force measurement of the airborne main inertial navigation system and the accurate air-dropped inertial navigation device, a matching model of angular velocity integration and specific force integration in the inertial system is established;

[0145] ​Step 4: Establish the Kalman filter state equation and complete the Kalman filter time update;

[0146] Step 5: Based on the integral obtained in step 3 and the state equation, the measurement equation is constructed;

[0147] Step 6: Complete Kalman filter measurement update;

[0148] Step 7: Complete the compensation of the attitude tracking error in the inertial system of the precise airdrop inertial navigation device; obtain the attitude matrix of the precise airdrop inertial navigation device at the end of alignment.

[0149] Example 4:

[0150] Based on Example 3, in step 2, the attitude differential equation in the airborne main inertial navigation inertial system is:

[0151]

[0152] in, Indicates the output angular velocity of the onboard main inertial navigation gyro The cross product antisymmetric matrix, Represents the coordinate system m of the airborne main inertial navigation carrier to the carrier inertial system i m The attitude transformation matrix, I3 represents the third-order unit matrix;

[0153] The attitude differential equation of the precision airdrop inertial navigation unit in the inertial system is:

[0154]

[0155] in, Indicates the gyro output angular velocity of the precision airdrop inertial navigation device The cross product antisymmetric matrix of ; Represents the coordinate system s of the airborne main inertial navigation carrier to the carrier inertial system i s The posture transformation matrix.

[0156] Example 5:

[0157] Based on Example 4, in step 3, the angular velocity measurement relationship is:

[0158]

[0159] Where, Represents the coordinate system s of the airborne main inertial navigation carrier to the carrier inertial system i s The posture transformation matrix; The gyro output angular velocity of the inertial navigation unit for accurate airdrop; For accurate airdrop inertial navigation unit angular velocity measurement projection on i s Error within the system; is the fixed mounting attitude matrix between the airborne master INS and the precision aerial delivery INS; is the attitude transformation matrix from the airborne master INS carrier coordinate system m to the carrier inertial system i m ; is the gyro output angular velocity of the airborne master INS; is the angular velocity of the precision aerial delivery INS relative to the airborne master INS, resulting from elastic deformation; is the elastic deformation residual term, considered as noise;

[0160] The specific force measurement relationship is:

[0161]

[0162] where, represents the projection of the specific force measurement of the precision aerial delivery INS into the i s system; is the error of the projection of the specific force measurement of the precision aerial delivery INS into the i s system; represents the projection of the specific force measurement of the airborne master INS into the i m system after arm compensation; is the arm compensation residual term, considered as noise.

[0163] Integrating the two equations representing the angular velocity measurement and the specific force measurement relationship, the calculation of the integral quantity is obtained:

[0164] Angular velocity integral of the precision aerial delivery INS:

[0165]

[0166] Angular velocity integral of the airborne master INS:

[0167]

[0168] Specific force integral of the precision aerial delivery INS:

[0169]

[0170] Specific force integral of the airborne master INS:

[0171]

[0172] Example 6:

[0173] On the basis of Example 5, in Step 4, the vectorized elements of the fixed mounting attitude matrix between the airborne master INS and the precision aerial delivery INS are selected Angular velocity integral error Specific force integral error Precise aerial delivery INS carrier inertial frame attitude error Precise aerial delivery INS gyro drift ε s Precise aerial delivery INS accelerometer bias As a state, the obtained Kalman filter state equation is:

[0174]

[0175] wherein,

[0176]

[0177] That is,

[0178] The system matrix A is The state transition matrix B is The process noise vector W is wherein, represents the projection of the precise aerial delivery INS specific force measurement in the i s frame; represents the attitude transformation matrix of the airborne main INS carrier coordinate system s to the carrier inertial frame i s ; w is the precise aerial delivery INS gyro measurement noise; a s is the precise aerial delivery INS accelerometer measurement noise; represents the projection of the precise aerial delivery INS angular velocity measurement in the i s frame.

Claims

1. A method for rapid transfer of alignment of an airdrop inertial navigation system with no singularity at any misalignment angle, characterized in that: Please follow the steps below to implement it: Step 1: Establish a quasi-inertial coordinate system with initial alignment at the starting moment; Step 2: After the alignment begins, the onboard main inertial navigation system and the precision airdrop inertial navigation system respectively update the attitude in the inertial system and solve the attitude matrix in real time. and ; Step 3: During the inertial navigation sampling period, based on the angular velocity and specific force measurements of the airborne main inertial navigation system and the precision airdrop inertial navigation system, a matching model of the angular velocity integral and the specific force integral in the inertial system is established; Step 4: Establish the Kalman filter state equation and complete the Kalman filter time update; Step 5: Based on the integral obtained in step 3 and the state equation, the measurement equation is constructed; Step 6: Complete Kalman filter measurement update; Step 7, complete the compensation of the attitude tracking error of the precise airdrop inertial navigation device in the inertial system; obtain the attitude matrix of the precise airdrop inertial navigation device at the end of alignment; Step 7 is as follows: Determine whether the transfer alignment time is over. If not, return to step 2 to continue. If it is over, complete the attitude tracking result of the precise airdrop inertial navigation device inertial system. The compensation is combined with the attitude update results of the precise airdrop inertial navigation device and the airborne main inertial navigation carrier coordinate system obtained in step 2 to obtain the current attitude matrix of the precise airdrop inertial navigation device. , that is, the transfer alignment process is completed; Among them, the current attitude matrix of the precision airdrop inertial navigation unit is: Where, is the airborne main inertial navigation attitude matrix at the end of alignment; It is the attitude tracking result under the airborne main inertial navigation inertial system; This is the attitude tracking result of the inertial system of the precise airdrop inertial navigation device; Fixed installation of attitude matrix between the airborne main inertial navigation system and the precision airdrop inertial navigation system.

2. The method for rapid transfer alignment of a precision airdrop inertial navigation system with no singularity at any misalignment angle according to claim 1, characterized in that: In step 2, the attitude differential equation under the airborne main inertial navigation inertial system is: in, Indicates the output angular velocity of the onboard main inertial navigation gyro The cross product antisymmetric matrix, Represents the coordinate system of the airborne main inertial navigation carrier To the carrier inertial system The posture transformation matrix, represents the third-order identity matrix; The attitude differential equation of the precision airdrop inertial navigation unit in the inertial system is: in, Indicates the gyro output angular velocity of the precision airdrop inertial navigation device The cross product antisymmetric matrix of ; Represents the coordinate system of the airborne main inertial navigation carrier To the carrier inertial system The posture transformation matrix.

3. The method for rapid transfer alignment of a precise airdrop inertial navigation system with no singularity at any misalignment angle according to claim 1, characterized in that: In step 3, the angular velocity measurement relationship is: Where, ; Represents the coordinate system of the airborne main inertial navigation carrier To the carrier inertial system The posture transformation matrix; The gyro output angular velocity of the inertial navigation unit for accurate airdrop; For accurate airdrop inertial navigation unit angular velocity measurement projection Error within the system; It is a fixed installation attitude matrix between the airborne main inertial navigation system and the precision airdrop inertial navigation system; Represents the coordinate system of the airborne main inertial navigation carrier To the carrier inertial system The posture transformation matrix; The gyro output angular velocity of the airborne main inertial navigation system; The angular velocity of the airdrop inertial navigation unit relative to the onboard main inertial navigation is generated by elastic deformation; is the residual term of elastic deformation, which is regarded as noise; The specific force measurement relationship is: Where, Indicates the precise airdrop inertial navigation unit force measurement in Projection within the system; For accurate airdrop inertial navigation unit force measurement projection Error within the system; Indicates that the airborne main inertial navigation specific force measurement is compensated by the lever arm. Projection within the system; is the residual term of the lever arm compensation, which is considered as noise.

4. The method for rapid transfer alignment of a precise airdrop inertial navigation system with no singularity at any misalignment angle according to claim 3, characterized in that: Integrate the two formulas that represent the relationship between angular velocity measurement and specific force measurement, and perform the integral The calculation is: Angular velocity integral of the precision airdrop inertial navigation unit: Airborne main inertial navigation angular velocity integral: Precision airdrop inertial navigation unit comparative force integral: Airborne main inertial navigation specific force integral: 。 5. The method for rapid transfer alignment of a precision airdrop inertial navigation system with no singularity at any misalignment angle according to claim 1, characterized in that: In step 4, select the fixed installation attitude matrix between the airborne main inertial navigation system and the precision airdrop inertial navigation system. Vectorized elements of , angular velocity integral error , specific integral error 2. Attitude error of the inertial system of the carrier of the precision airdrop inertial navigation device , precision airdrop inertial navigation device gyro drift , Accelerometer bias of precision airdrop inertial navigation device As the state, the obtained Kalman filter state equation is: in, Right now, System Matrix for ;State transition matrix for ; Process noise vector for ;in, Indicates the precise airdrop inertial navigation unit force measurement in Projection within the system; Represents the coordinate system of the airborne main inertial navigation carrier To the carrier inertial system The posture transformation matrix; Measuring noise on inertial navigation unit gyros for precision airdrops; Measurement noise of accelerometers in inertial navigation units for accurate airdrops; Indicates the angular velocity measurement of the precise airdrop inertial navigation device Projection within the system.

6. The method for rapid transfer alignment of a precision airdrop inertial navigation system with no singularity at any misalignment angle according to claim 1, characterized in that: The measurement equation constructed in step 5 is: In the above formula, In the above formula, represents the third-order identity matrix, express dimensional zero matrix, , , , , , , , , , , ; are the specific force and angular velocity integral of the precision airdrop inertial navigation device respectively; They are the specific force and angular velocity integral of the airborne main inertial navigation respectively.

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