Arbitrary misalignment angle non-singular rapid transfer alignment method of precise air-drop inertial navigation device

Abstract

The invention discloses a non-singular rapid transfer alignment method for any misalignment angle of a precise air-drop inertial navigation device, which comprises the following steps: after alignment is started, an airborne main inertial navigation device and the precise air-drop inertial navigation device respectively carry out attitude updating under an inertial system, and solve attitude matrixes # imgabs0 # and # imgabs1 # in an inertial navigation sampling period in real time; the method comprises the following steps: establishing a matching model of an angular velocity integral and a specific force integral in an inertial system based on angular velocity and specific force measurement of an airborne main inertial navigation device and a precise air-drop inertial navigation device; a Kalman filtering state equation is established, and Kalman filtering time updating is completed; constructing a measurement equation according to the obtained integral quantity in combination with a state equation; completing Kalman filtering measurement updating; the compensation of the attitude tracking error under the inertial system of the precise air-drop inertial navigation device is completed; and obtaining an attitude matrix at the alignment ending moment of the precise air-drop inertial navigation device. According to the method, transfer alignment can be rapidly completed under simple hovering maneuver of the aerial carrier.

Description

Technical Field

[0001] The invention belongs to the technical field of precise airdrop control of equipment inertial navigation equipment, and relates to a method for quick transfer and alignment of any misalignment angle of a precise airdrop inertial navigation device without singularity. Background Art

[0002] The airdrop system is a technology that uses parachutes to deliver personnel and materials to designated locations. The traditional airdrop system is affected by the accuracy of factors such as navigation and guidance, and the airdropped materials are generally scattered everywhere like "flowers scattered by heaven". The precision airdrop system is a perfect combination of modern navigation (especially inertial navigation technology), guidance and control technology and traditional airdrop technology. It can realize functions such as airdrop track planning, parachute control, atmospheric estimation, and long-distance precision delivery, which greatly expands the practical application of airdrop. It can be said that whether there is an inertial navigation device, satellite navigation system and radio navigation device is the main difference between modern precision airdrop and traditional airdrop, and it is also the mainstream direction of airdrop development.

[0003] As a real-time navigation method of dead reckoning, inertial navigation has complete autonomy and a natural combination advantage with satellite navigation systems. However, before entering the navigation working state, the inertial navigation device first needs to determine its own initial attitude information, that is, the initial alignment. The length of the alignment time represents the rapid response capability of the inertial navigation system.

[0004] Due to the particularity of the precision airdrop system, it is required to complete the initial attitude determination in a short time. It must also meet the requirements of the actual airdrop carrier platform and cannot impose restrictions on the installation method of the airdrop inertial navigation device. Therefore, a simple and easy method is needed that can adapt to the maneuvering conditions of the airdrop carrier and quickly determine the initial attitude without any singularity at any misalignment angle.

[0005] In traditional transfer alignment, the misalignment angle is mainly divided into a linear model for small misalignment angles and a nonlinear model for large misalignment angles. The installation relationship between the main and sub-inertial navigation systems needs to be confirmed in advance. For large misalignment angles, nonlinear filtering needs to be used. Therefore, there are problems of large calculation amount and low estimation accuracy. Summary of the invention

[0006] The purpose of the present invention is to provide a method for rapid transfer alignment of an accurate airdrop inertial navigation device without singularity at any misalignment angle, which can quickly complete the transfer alignment under a simple circling maneuver of a carrier aircraft.

[0007] The technical solution adopted by the present invention is a method for quickly transferring and aligning an arbitrary misalignment angle of a precision airdrop inertial navigation device without singularity, which is specifically implemented according to the following steps:

[0008] Step 1, establishing a quasi-inertial coordinate system with initial alignment at the 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 and the precision airdrop inertial navigation device, 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, construct the measurement equation based on the integral obtained in step 3 and the state equation;

[0013] Step 6, complete Kalman filter measurement update;

[0014] Step 7, complete the compensation of the attitude tracking error of the precision airdrop inertial navigation device in the inertial system; obtain the attitude matrix of the precision 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 main onboard 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 device 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] In the formula, 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; It is a fixed installation attitude matrix between the airborne main inertial navigation and the precision airdrop inertial navigation unit; Represents the coordinate system m of the airborne main inertial navigation carrier to the carrier inertial system i m The posture transformation matrix; It is 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;

[0025] The specific force measurement relationship is:

[0026]

[0027] In the formula, Indicates the specific force measurement of the precise airdrop inertial navigation device at i s Projection within the system; For accurate airdrop of inertial navigation unit, force measurement projection is performed on i s Error within the system; It means that the airborne main inertial navigation specific force measurement is compensated by the lever arm at i m Projection within the system; is the residual term of the lever arm compensation, which is considered as noise.

[0028] Integrate the two formulas that represent the relationship between angular velocity measurement and specific force measurement to obtain the integral quantity The calculation is:

[0029] Angular velocity integral of precision airdrop inertial navigation unit:

[0030]

[0031] Airborne main inertial navigation angular velocity integral:

[0032]

[0033] Precision airdrop inertial navigation unit specific force integral:

[0034]

[0035] Airborne main inertial navigation force integral:

[0036]

[0037] In step 4, select the fixed installation attitude matrix between the airborne main inertial navigation device and the precision airdrop inertial navigation device. The vectorized elements of Angular velocity integral error Specific force integral error Attitude error of inertial system of carrier of precision airdrop inertial navigation device Gyro drift of precision airdrop inertial navigation unit ε s , Accelerometer bias of precision airdrop inertial navigation device As the state, the Kalman filter state equation is obtained as:

[0038]

[0039] in,

[0040]

[0041] Right now,

[0042] The system matrix A is The state transfer matrix B is The process noise vector W is in, Indicates the specific force measurement of the precise airdrop inertial navigation device at i s Projection within the system; Represents the coordinate system s of the airborne main inertial navigation carrier to the carrier inertial system i s The posture transformation matrix; Gyro measurement noise for accurate airdrop inertial navigation unit; a s Measuring noise of accelerometers in inertial navigation units for accurate airdrops; Indicates the angular velocity measurement of the precise airdrop inertial navigation device at i s Projection within the system.

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

[0044]

[0045] In the above formula,

[0046]

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

[0048]

[0049] They are the specific force and angular velocity integral of the precision airdrop inertial navigation device; They are respectively the specific force and angular velocity integral of the airborne main inertial navigation.

[0050] Step 7 is as follows:

[0051] Determine whether the transfer alignment time is over. If not, return to step 2 to continue execution. If it is over, complete the attitude tracking result under the inertial system of the precision airdrop inertial navigation device. 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 The transfer alignment process is completed.

[0052] In step 7, the current attitude matrix of the precision airdrop inertial navigation unit is:

[0053]

[0054] In the formula, 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; It is the attitude tracking result of the inertial system of the precise airdrop inertial navigation device; To fix the attitude matrix between the airborne main inertial navigation device and the precision airdrop inertial navigation device.

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

[0056] (1) The method of the present invention uses the fixed installation attitude matrix between the airborne main inertial navigation system and the precision airdrop inertial navigation system as the filtering state, and the established transfer alignment filtering model is a unified linearized alignment model under any misalignment angle, thereby avoiding the problems of nonlinear filtering and singular points in traditional technologies;

[0057] (2) The method of the present invention establishes an alignment model based on angular velocity integral and specific force integral, which can realize the rapid alignment of the precise airdrop inertial navigation device;

[0058] (3) The method of the present invention has no special requirements for the installation of the precision airdrop inertial navigation device, and can quickly complete the initial alignment under the condition of a simple circling maneuver of the carrier aircraft, thereby improving the combat effectiveness and airdrop accuracy of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0060] Figure 2 : is a diagram of the estimation result of the small-angle installation error angle under the hovering maneuver of the carrier aircraft in an embodiment of the present invention;

[0061] Figure 31 is a diagram showing the estimation result of the large-angle installation error angle during the hovering maneuver of the carrier aircraft in an embodiment of the present invention. DETAILED DESCRIPTION

[0062] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0063] The invention discloses a method for fast transfer alignment of an accurate airdrop inertial navigation device without singularity at any misalignment angle. The method utilizes the output information of the airborne main inertial navigation to complete the transfer alignment of the accurate airdrop inertial navigation device only under the condition of circling maneuver. The process is as follows: Figure 1 As shown, the specific implementation steps are as follows:

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

[0065] Step 2: After the alignment begins, the carrier coordinate systems of the airborne main inertial navigation and the precision airdrop inertial navigation device are updated in their respective carrier inertial systems to complete the attitude matrix in real time. and Calculation.

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

[0067]

[0068] 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 posture transformation matrix, I3 represents the third-order identity matrix.

[0069] The attitude differential equation of the precision airdrop inertial navigation device in the inertial system is:

[0070]

[0071] 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.

[0072] Step 3: During the inertial navigation sampling period, based on the angular velocity and specific force measurements of the airborne main inertial navigation and the precision airdrop inertial navigation device, a matching model of the angular velocity integral and specific force integral in the inertial system is established. The angular velocity measurement relationship is:

[0073]

[0074] In the formula, For accurate airdrop inertial navigation unit angular velocity measurement projection on i s Error within the system; It is a fixed installation attitude matrix between the airborne main inertial navigation and the precision airdrop inertial navigation unit; 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 and is regarded as noise.

[0075] The specific force measurement relationship is:

[0076]

[0077] In the formula, Indicates the specific force measurement of the precise airdrop inertial navigation device at i s Projection within the system; For accurate airdrop of inertial navigation unit, force measurement projection is performed on i s Error within the system; It means that the airborne main inertial navigation specific force measurement is compensated by the lever arm at i m Projection within the system; is the residual term of the lever arm compensation, which is considered as noise.

[0078] Integrate formula (3) and (4) to obtain the integral Calculation of , we get:

[0079] Angular velocity integral of precision airdrop inertial navigation unit:

[0080]

[0081] Airborne main inertial navigation angular velocity integral:

[0082]

[0083] Precision airdrop inertial navigation unit specific force integral:

[0084]

[0085] Airborne main inertial navigation force integral:

[0086]

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

[0088] Select the fixed installation attitude matrix between the airborne main inertial navigation unit and the precision airdrop inertial navigation unit The vectorized elements of Angular velocity integrated error Specific force integral error Attitude error of inertial system of carrier of precision airdrop inertial navigation device Gyro drift of precision airdrop inertial navigation unit ε s , Accelerometer bias of precision airdrop inertial navigation device As the state, that is, the Kalman filter state is:

[0089]

[0090] in, vec(·) means connecting the rows of the matrix to form a column vector.

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

[0092]

[0093] In the formula, Measuring gyro noise for precision airdrop inertial navigation units.

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

[0095]

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

[0097]

[0098] In the formula, w a s They are the random constant zero bias and measurement noise of the accelerometer of the precision airdrop inertial navigation unit, respectively.

[0099] Assume the system state equation is as follows:

[0100]

[0101] in,

[0102]

[0103] Right now,

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

[0105] Step 5: Based on the integral 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),

[0109]

[0110] In formula (16), I3 represents the 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, determine whether the transfer alignment time has ended. If not, return to step 2 to continue. If the transfer alignment time has ended, the attitude tracking result under the inertial system of the precision airdrop inertial navigation device is completed. 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 The transfer alignment process is completed.

[0114] The current attitude matrix of the precision airdrop inertial navigation unit is:

[0115]

[0116] In the formula, 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; It is the attitude tracking result of the inertial system of the precise airdrop inertial navigation device; To fix the attitude matrix between the airborne main inertial navigation device and the precision airdrop inertial navigation device.

[0117] Embodiment 1:

[0118] In step 1, a quasi-inertial coordinate system is established at the start time of the initial alignment. Specifically, the relevant coordinate systems involved in the transfer alignment process are defined as follows:

[0119] (1) Coordinate system of the carrier of the precision airdrop inertial navigation device (S system)

[0120] Use ox s y s z s Indicates that the origin of the coordinates is located at the sensitive center of the precision airdrop inertial navigation unit IMU, ox s Axis along the horizontal axis of the posture to the right, oy s Axis forward along the horizontal axis of posture; ox s,oy s oz s Construct a right-handed orthogonal coordinate system.

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

[0122] Use ox m y m z m Indicates that the origin of the coordinate system is located at the sensitive center of the onboard main inertial navigation IMU, ox m Axis along the horizontal axis of the posture to the right, oy m Axis forward along the horizontal axis of posture; ox m ,oy m oz m Construct a right-handed orthogonal coordinate system.

[0123] (3) Inertial system of the carrier of the precision airdrop inertial navigation device (i s Tie)

[0124] At the initial moment of alignment, the carrier coordinate system s of the precision airdrop inertial navigation device is artificially "solidified" in the inertial space to obtain the carrier inertial system i of the precision airdrop inertial navigation device. s .

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

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

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

[0128] Use ox n y n z n Indicates that the navigation coordinate system is selected as the northeast celestial geographic coordinate system.

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

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

[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 device and the precision airdrop inertial navigation device is completed according to the Kalman filter filtering results. Calculation and accurate attitude tracking results of airdrop inertial navigation device in inertial system After compensation, at the end of alignment, the initial attitude matrix of the precise airdrop inertial navigation device (17) can be obtained.

[0134] Embodiment 2:

[0135] Simulation conditions: The total simulation time is 10s, the aircraft tilt angle is 15°, the turn radius is 1000m, the turn speed is 180m / s, the gyro drift error in the precision airdrop inertial navigation device is 1° / h, and the random walk noise is The accelerometer zero position is 200ug and the random noise is The inertial navigation sampling period is 10ms.

[0136] The Euler angle method is used to set the fixed installation attitude relationship between the airborne main inertial navigation device and the precision airdrop inertial navigation device, which is divided into two cases: small attitude angle and large attitude angle.

[0137] The small attitude angle is set as follows: pitch angle is 1°; roll angle is 2°; azimuth angle is 3°.

[0138] The maximum attitude angle is set as: pitch angle 30°; roll angle 50°; azimuth angle 60°.

[0139] Figure 2 and Figure 3 The estimation result diagrams of small-angle and large-angle installation error angles respectively show that under the condition of aircraft circling maneuver, no matter the size of the installation error angle, the method of the present invention can correctly estimate it within 10 seconds, that is, quickly complete high-precision alignment.

[0140] Embodiment 3:

[0141] The method for the non-singular rapid transfer alignment of any misalignment angle of the precision airdrop inertial navigation device is specifically implemented in the following steps:

[0142] Step 1, establishing a quasi-inertial coordinate system with initial alignment at the starting time;

[0143] 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

[0144] Step 3: During the inertial navigation sampling period, based on the angular velocity and specific force measurements of the airborne main inertial navigation and the precision airdrop inertial navigation device, a matching model of the angular velocity integral and the specific force integral 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, construct the measurement equation based on the integral obtained in step 3 and the state equation;

[0147] Step 6, complete Kalman filter measurement update;

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

[0149] Embodiment 4:

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

[0151]

[0152] in, Indicates the output angular velocity of the main onboard 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;

[0153] The attitude differential equation of the precision airdrop inertial navigation device 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] Embodiment 5:

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

[0158]

[0159] In the formula, 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; It is a fixed installation attitude matrix between the airborne main inertial navigation and the precision airdrop inertial navigation unit; Represents the coordinate system m of the airborne main inertial navigation carrier to the carrier inertial system i m The posture transformation matrix; It is 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;

[0160] The specific force measurement relationship is:

[0161]

[0162] In the formula, Indicates the specific force measurement of the precise airdrop inertial navigation device at i s Projection within the system; For accurate airdrop of inertial navigation unit, force measurement projection is performed on i s Error within the system; It means that the airborne main inertial navigation specific force measurement is compensated by the lever arm at i m Projection within the system; is the residual term of the lever arm compensation, which is considered as noise.

[0163] Integrate the two formulas that represent the relationship between angular velocity measurement and specific force measurement to obtain the integral quantity Calculation of , we get:

[0164] Angular velocity integral of precision airdrop inertial navigation unit:

[0165]

[0166] Airborne main inertial navigation angular velocity integral:

[0167]

[0168] Precision airdrop inertial navigation unit specific force integral:

[0169]

[0170] Airborne main inertial navigation force integral:

[0171]

[0172] Embodiment 6:

[0173] Based on Example 5, in step 4, a fixed installation attitude matrix is ​​selected between the airborne main inertial navigation device and the precision airdrop inertial navigation device. The vectorized elements of Angular velocity integrated error Specific force integral error Attitude error of inertial system of carrier of precision airdrop inertial navigation device Gyro drift of precision airdrop inertial navigation unit ε s , Accelerometer bias of precision airdrop inertial navigation device As the state, the Kalman filter state equation is obtained as:

[0174]

[0175] in,

[0176]

[0177] Right now,

[0178] The system matrix A is The state transfer matrix B is The process noise vector W is in, Indicates the specific force measurement of the precise airdrop inertial navigation device at i s Projection within the system; Represents the coordinate system s of the airborne main inertial navigation carrier to the carrier inertial system i s The posture transformation matrix; Gyro measurement noise for accurate airdrop inertial navigation unit; a s Measuring noise of accelerometers in inertial navigation units for accurate airdrops; Indicates the angular velocity measurement of the precise airdrop inertial navigation device at i s Projection within the system.

Claims

1. A method for fast transfer alignment of an arbitrary misalignment angle of an accurate airdrop inertial navigation device without singularity, characterized in that: Follow the steps below to implement it: Step 1, establishing a quasi-inertial coordinate system with initial alignment at the starting time; 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 and the precision airdrop inertial navigation device, 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, construct the measurement equation based on the integral obtained in step 3 and the state equation; Step 6, complete Kalman filter measurement update; Step 7, complete the compensation of the attitude tracking error of the precision airdrop inertial navigation device in the inertial system; obtain the attitude matrix of the precision airdrop inertial navigation device at the end of alignment.

2. The method for fast transfer alignment of an accurate airdrop inertial navigation device 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 main onboard 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 posture transformation matrix, I3 represents the third-order identity matrix; The attitude differential equation of the precision airdrop inertial navigation device 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 s of the airborne main inertial navigation carrier to the carrier inertial system i s The posture transformation matrix.

3. The method for fast transfer alignment of an arbitrary misalignment angle without singularity of a precision airdrop inertial navigation device according to claim 1, characterized in that: In step 3, the angular velocity measurement relationship is: In the formula, 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; It is a fixed installation attitude matrix between the airborne main inertial navigation and the precision airdrop inertial navigation unit; Represents the coordinate system m of the airborne main inertial navigation carrier to the carrier inertial system i m The posture transformation matrix; It is 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: In the formula, Indicates the specific force measurement of the precise airdrop inertial navigation device at i s Projection within the system; For accurate airdrop of inertial navigation unit, force measurement projection is performed on i s Error within the system; It means that the airborne main inertial navigation specific force measurement is compensated by the lever arm at i m Projection within the system; is the residual term of the lever arm compensation, which is considered as noise.

4. The method for fast transfer alignment of an accurate airdrop inertial navigation device 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 to obtain the integral quantity The calculation is: Angular velocity integral of precision airdrop inertial navigation unit: Airborne main inertial navigation angular velocity integral: Precision airdrop inertial navigation unit specific force integral: Airborne main inertial navigation force integral:

5. The method for fast transfer alignment of an arbitrary misalignment angle without singularity of a precision airdrop inertial navigation device according to claim 1, characterized in that: In step 4, select the fixed installation attitude matrix between the airborne main inertial navigation device and the precision airdrop inertial navigation device. The vectorized elements of Angular velocity integral error Specific force integral error Attitude error of inertial system of carrier of precision airdrop inertial navigation device Gyro drift of precision airdrop inertial navigation unit ε s , Accelerometer bias of precision airdrop inertial navigation device As the state, the Kalman filter state equation is obtained as: in, Right now, The system matrix A is The state transfer matrix B is The process noise vector W is in, Indicates the specific force measurement of the precise airdrop inertial navigation device at i s Projection within the system; Represents the coordinate system s of the airborne main inertial navigation carrier to the carrier inertial system i s The posture transformation matrix; Gyro measurement noise for accurate airdrop inertial navigation unit; a s Measuring noise of accelerometers in inertial navigation units for accurate airdrops; Indicates the angular velocity measurement of the precise airdrop inertial navigation device at i s Projection within the system.

6. The method for fast transfer alignment of an accurate airdrop inertial navigation device 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, I3 represents the third-order unit matrix, 0 n×m represents an n×m-dimensional zero matrix, They are the specific force and angular velocity integral of the precision airdrop inertial navigation device; They are respectively the specific force and angular velocity integral of the airborne main inertial navigation.

7. The method for fast transfer alignment of an arbitrary misalignment angle without singularity of a precision airdrop inertial navigation device according to claim 1, characterized in that: Step 7 is as follows: Determine whether the transfer alignment time is over. If not, return to step 2 to continue execution. If it is over, complete the attitude tracking result under the inertial system of the precision airdrop inertial navigation device. 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 The transfer alignment process is completed.

8. The method for fast transfer alignment of an accurate airdrop inertial navigation device with no singularity at any misalignment angle according to claim 7, characterized in that: In step 7, the current attitude matrix of the precision airdrop inertial navigation unit is: In the formula, 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; It is the attitude tracking result of the inertial system of the precise airdrop inertial navigation device; To fix the attitude matrix between the airborne main inertial navigation device and the precision airdrop inertial navigation device.

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