A method for estimating the roll angle measurement error of a rolling missile with linear deviation measurement noise

Abstract

The purpose of the present invention is to provide a method for estimating the roll angle measurement error of a rolling missile containing line deviation measurement noise. The method comprises the following steps: treating the missile as a particle to construct a system second-order low-pass filter and a nonlinear extended state observer, and then bringing the sampled line deviation data into the filter and the state observer to obtain the roll angle measurement error. In order to make the result more accurate, the roll angle measurement error value is obtained by calculating the average value of multiple roll angle measurement errors obtained. The method can estimate the missile roll angle measurement error more accurately when the line deviation contains measurement noise, so as to be used for correction and compensation of the control system.

Description

Technical Field

[0001] The invention relates to a rolling missile rolling angle measurement error estimation method containing linear deviation measurement noise, and belongs to the technical field of laser beam-riding guided rolling missile guidance control. Background Art

[0002] Laser beam-riding guided missiles form guidance instructions based on the position line deviation from the center of the laser beam. Laser beam-riding guided rolling missiles use gyroscopes to sense the spatial attitude of the missile body, but due to the error in the calibration of the gravity direction by the gyroscope, the measured roll angle has an error. The existence of roll angle measurement error will cause a deviation between the theoretical control force direction and the actual control force direction, resulting in coupling between the missile's pitch and yaw channel control and spiral motion in the trajectory. Estimation of roll angle measurement error is of great significance to improving the hit accuracy of laser beam-riding guided rolling missiles. Estimation of roll angle measurement error requires the use of line deviation data, but the line deviation data sensed by the missile will inevitably have measurement noise. Derivation of the noisy measurement data will further amplify the noise, and it is ultimately difficult to obtain the roll angle measurement error.

[0003] At present, the sun azimuth angle measurement method, accelerometer method and magnetic detection method are mostly used to compensate for the missile roll angle measurement error. However, the above methods will inevitably introduce additional sensors into the missile body, increasing the weight of the missile body. For laser beam-riding guided missiles, which are generally used for anti-tank and low-altitude defense, the introduction of expensive high-precision sensors will reduce their low-cost advantage. Summary of the invention

[0004] The present invention proposes a method for estimating the roll angle measurement error of a rolling missile containing line deviation measurement noise. When the line deviation contains measurement noise, the missile roll angle measurement error can be estimated more accurately for correction and compensation of the control system.

[0005] A method for estimating the roll angle measurement error of a rolling missile containing linear deviation measurement noise comprises the following steps:

[0006] Step 1: The laser receiving device on the missile processes the received laser signal and obtains the linear deviation Δx and Δy between the missile and the target. The controller on the missile obtains the control force F according to the missile control force. x2 、F y2 ;

[0007] Step 2: Input the line deviation into the second-order low-pass filter and then into the nonlinear extended state observer to obtain the

[0008] Step 3: Based on the divided control force F x2 、F y2, missile mass m and the extended state observer calculated Calculate the roll angle measurement error δ;

[0009] Step 4: Repeat steps 1 to 4 N times, perform average filtering on the obtained results, and obtain the final roll angle measurement error estimate.

[0010] Furthermore, the transfer function of the second-order low-pass filter of the present invention is:

[0011]

[0012] Among them, Y(s) is the frequency domain expression of the signal after filtering, S is a complex parameter, ω is the cutoff frequency, and R(s) is the frequency domain expression of the signal input to the filter after Laplace transform.

[0013] Furthermore, the nonlinear extended state observer of the present invention:

[0014] e=z1-y

[0015]

[0016]

[0017]

[0018] Among them, β1, β2, β3, δ1, α1, α2 are set values, and the saturation function fal(e, α1, δ1) is expressed as:

[0019]

[0020] The saturation function fal(e,α2,δ1) is expressed as:

[0021]

[0022] Among them, sgn(e) is the sign function, which outputs the positive or negative sign of e.

[0023] Furthermore, the line deviation is input into a second-order low-pass filter and then into a nonlinear extended state observer to obtain the It includes the following:

[0024] The line deviations Δx and Δy are Laplace transformed and input into the second-order low-pass filter as R(s), and the output Y(s) is recorded as Y1(s) and Y2(s) respectively. Y1(s) and Y2(s) are inversely Laplace transformed and respectively brought into the variable y in the extended state observer, and the z3 is solved and recorded as

[0025] Further, the component F x2 、F y2 , missile mass m and the extended state observer calculated Calculate the roll angle measurement error δ, including the following, based on the component F x2 、F y2 , missile mass m and the extended state observer calculated The roll angle measurement error δ is obtained by simultaneous solution:

[0026]

[0027] Beneficial effects:

[0028] First, the amount of calculation used in the calculation process of this method does not require the addition of additional sensors to the original missile body, and can be collected only by relying on the original laser receiving device and controller on the missile, avoiding the increase in missile body weight and manufacturing cost after adding sensors like the traditional methods of solar azimuth measurement, accelerometer method and magnetic detection method.

[0029] Second, in the calculation process of this method, in order to eliminate the measurement noise in the line deviation signal, a second-order low-pass filter is constructed, and the addition of a saturation function fal(e, α1, δ) to the nonlinear extended state observer can suppress signal jitter, making the system more accurate.

[0030] Third, due to the existence of line deviation measurement noise, the roll angle measurement error obtained in step three will oscillate within a certain range. In order to further obtain an accurate roll angle measurement error, the result obtained in step three is averaged and filtered to effectively eliminate oscillation and achieve higher calculation accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0032] Figure 1 A schematic diagram of the coordinate system.

[0033] Figure 2 Flowchart for roll angle measurement error estimation. DETAILED DESCRIPTION

[0034] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0035] The embodiment of the present application proposes a method for estimating the roll angle measurement error of a laser beam-riding guided rolling missile containing line deviation measurement noise. The method can more accurately estimate the missile roll angle measurement error when the line deviation contains measurement noise, which is used for correction and compensation of the control system.

[0036] A method for estimating the roll angle measurement error of a rolling missile containing linear deviation measurement noise comprises the following steps (see attached Figure 2 shown):

[0037] Step 1: The laser receiving device on the missile processes the received laser signal and continuously obtains the distance deviation Δx and Δy between the missile and the target. The controller on the missile obtains the sub-control force F according to the missile control force. x2 、F y2 ;

[0038] In the calculation process of this embodiment, the calculation of the distance deviation and the component control force is equivalent to setting the standard coordinate system Ox1y1, taking the missile M as a mass point with a mass of m, T as the target point, and taking the missile center of mass as the origin. Its x1 and y1 axes are located in the vertical plane of the laser beam axis, the x1 axis points to the horizontal direction, and the y1 axis points to the opposite direction of the component force of gravity in the plane; setting the moving coordinate system Ox2y2 as follows: taking the missile center of mass as the origin, the angle between the moving coordinate system and the standard coordinate system is the roll angle measurement error δ, and Ox1 is positive when it rotates counterclockwise to Ox2; F x2 、F y2 They are the missile control forces acting on the x2 and y2 directions in the moving coordinate system. The coordinates of the missile M are (x M ,y M ), the coordinates of the missile T are (x T ,y T ), the position line deviation between the missile and the target in the standard coordinate system is:

[0039]

[0040] The missile kinematics and dynamics are described in standard coordinates as:

[0041]

[0042] Where V Mx 、V My are the velocity values ​​of the missile in the x and y directions.

[0043] Step 2: Construct a second-order low-pass filter and a nonlinear extended state observer for the system. Input the line deviation into the second-order low-pass filter and then into the nonlinear extended state observer to obtain the

[0044] If the target acceleration aT = 0 or the missile acceleration is much greater than the target acceleration, i.e. a T <<a M , in the x direction in the standard coordinate system, let x1 = Δx, Establish the system state equation, where the output y1 is the line deviation in the x1 direction:

[0045]

[0046]

[0047]

[0048] In the y direction of the standard coordinate system, let x3 = Δy, Establish the system state equation, where the output y2 is the line deviation in the y1 direction:

[0049]

[0050]

[0051]

[0052] In the above system state equation, f becomes the unknown part due to the existence of the unknown term δ.

[0053] The line deviation data y1 and y2 are Laplace transformed and input into the second-order low-pass filter as R(s) to construct a second-order low-pass filter, and its transfer function is:

[0054]

[0055] Among them, Y(s) is the frequency domain expression of the signal after filtering, ω is the cutoff frequency. When its value is less than the frequency of the noise signal, the filtering effect is better. The output Y(s) can be obtained through the above transfer function and recorded as Y1(s) and Y2(s), respectively. After inverse Laplace transform, new y1 and y2 are obtained respectively.

[0056] Then construct the nonlinear extended state observer:

[0057] e=z1-y

[0058]

[0059]

[0060]

[0061] In this embodiment, β1=100, β2=300, β3=1000, δ1=0.01, α1=0.5, α2=0.25 are set, and the saturation function fal(e, α1, δ) is used to suppress signal jitter, which is expressed as:

[0062]

[0063] Then z1(t)→x1(t), z2(t)→x2(t), z3(t)→f.

[0064] Substitute the filtered line deviation data y1 and y2 into the variable y in the extended state observer, and solve for z3 calculated by the extended state observer, which is recorded as have

[0065]

[0066] Step 3: Based on the component F x2 、F y2 and the extended state observer calculated Calculate δ and solve the roll angle measurement error δ:

[0067]

[0068] Step 4: Repeat steps 1 to 3 for a total of N times, perform average filtering on the obtained results, and obtain the final roll angle measurement error estimate. Due to the existence of line deviation measurement noise, the roll angle measurement error obtained will oscillate within a certain range. In order to further obtain an accurate roll angle measurement error, the result needs to be averaged and filtered. The average filtering calculation process is as follows:

[0069]

[0070] Where N is the number of repetitions, δ n is the roll angle measurement error calculated in the nth process, is the final estimated value of the roll angle measurement error.

[0071] The gravity, gravity compensation and control force mentioned in the present invention should be understood in a broad sense. When the laser beam is non-horizontal, the above-mentioned force should be understood as the component of the actual force in the plane perpendicular to the laser beam.

[0072] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A method for estimating the roll angle measurement error of a rolling missile containing linear deviation measurement noise, characterized in that: The steps include: Step 1: The laser receiving device on the missile processes the received laser signal and obtains the linear deviations Δx and Δy between the missile and the target. The controller on the missile obtains the control force F according to the missile control force. x2 、F y2 ; Step 2: Input the line deviation into the second-order low-pass filter and then into the nonlinear extended state observer to obtain the Step 3: Based on the divided control force F x2 、F y2 , missile mass m and the extended state observer calculated Calculate the roll angle measurement error δ; Step 4: Repeat steps 1 to 3 for a total of N times, perform average filtering on the obtained results, and obtain the final roll angle measurement error estimate. The transfer function of the second-order low-pass filter is: Among them, Y(s) is the frequency domain expression of the signal after filtering, s is a complex parameter, ω is the cutoff frequency, and R(s) is the frequency domain expression of the signal input to the filter after Laplace transform; The nonlinear extended state observer: e=z1-y Among them, β1, β2, β3, δ1, α1, α2 are set values, and the saturation function fal(e, α1, δ1) is expressed as: The saturation function fal(e,α2,δ1) is expressed as: Among them, sgn(e) is the sign function, which outputs the positive and negative sign of e; The line deviation is input into a second-order low-pass filter and then into a nonlinear extended state observer to obtain the It includes the following: The line deviations Δx and Δy are Laplace transformed and input into the second-order low-pass filter as R(s), and the output Y(s) is recorded as Y1(s) and Y2(s) respectively. Y1(s) and Y2(s) are inversely Laplace transformed and substituted into the variable y in the extended state observer, and the z3 is solved and recorded as 2. The method according to claim 1, characterized in that The control force F x2 、F y2 , missile mass m and the extended state observer calculated Calculating the roll angle measurement error δ includes the following contents, based on the component control force F x2 、F y2 , missile mass m and the extended state observer calculated The roll angle measurement error δ is obtained by simultaneous solution:

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