A complex profile rudder wing precision non-contact angle measurement method and device

Abstract

The present application relates to a kind of complex profile rudder wing precision non-contact angle measurement method and device, belong to artillery shell manufacturing technical field;The method includes symmetrically arranging three groups of non-collinear laser displacement sensors, ensure that laser beams are parallel and perpendicular to plumb surface;The optical axis is calibrated using precision piezoelectric actuator, according to the principle of laser triangulation, the spatial coordinate vector of laser spot at different time is calculated;The deflection angle of rudder wing is solved by calculating the normal vector of the plane reconstructed before and after deflection;The method uses the multiple laser displacement sensors arranged symmetrically based on the principle of differential plane reconstruction, realizes the non-contact measurement of the deflection angle of complex profile rudder wing;Not only solve the technical limitations such as low test efficiency, poor precision, visual field obstruction, data loss and other technical limitations of existing rudder wing contact indirect angle measurement, but also can efficiently and accurately realize the accurate measurement of the small angle of rudder wing.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of shell manufacturing, in particular to a complex profile rudder wing precision non-contact angle measurement method and device. BACKGROUND

[0002] To ensure the precision of guided shells, the flight attitude and trajectory of the shell body are controlled by the rudder wing, so it is necessary to ensure the precision of the rotation angle of the complex profile rudder wing. Since the deflection of the rudder wing is realized through the transmission chain of the power mechanism, the actuator and the action mechanism, errors are introduced through the transmission link, which will cause errors between the actual execution deflection angle of the rudder wing and the control instruction deflection angle. Therefore, in order to realize the closed loop / half closed loop error compensation of the rudder wing rotation angle, high requirements are put forward for the angle measurement accuracy, which should reach 0.03° (<1 mrad).

[0003] The existing rudder wing rotation angle quality detection of guided shells mainly relies on the servo motor of the detection unit to rotate at the same angle, and evaluates the accuracy of the rudder wing rotation angle by recording the contact load change of the force sensor, because the rudder wing presents a complex profile of asymmetric curvature. The above-mentioned contact type indirect rotation angle measurement method based on a circular grating has the technical limitations of low test efficiency and poor accuracy. At present, the non-contact measurement of the rudder wing rotation angle mainly includes laser non-contact and vision measurement based angle measurement technology. The three-dimensional space coordinates of the feature points of the complex rudder wing profile are collected and reconstructed by a binocular or multi-view vision system. However, the visual detection system is easy to be blocked by the field of view, and information is easy to be lost when the object surface features are extracted and reconstructed through images, which introduces additional measurement errors, and the visual measurement technology has low measurement accuracy.

[0004] With the measurement accuracy of fiber, laser and other linear displacement sensors reaching nanometer level, and the installation size tending to miniaturization, a new idea is provided for the measurement of the rudder wing rotation angle. Usually, the linear displacement is measured by the sensor, and then the angle is converted, but the applicability to the complex profile rudder wing is poor. SUMMARY

[0005] In view of the poor applicability and low measurement accuracy of the existing technology to the complex profile rudder wing, the present application provides a complex profile rudder wing precision non-contact angle measurement method and device, thereby solving the problems existing in the prior art.

[0006] A complex profile rudder wing precision non-contact angle measurement method, comprising the following steps:

[0007] Obtaining three laser spots formed by a single laser displacement sensor on the complex profile rudder wing at the initial position of the complex profile rudder wing and three laser spots on the symmetric side thereof;

[0008] According to three laser spots formed by the single laser displacement sensor on the complex surface rudder wing at the initial time and three laser spots formed on the symmetric side, a first planar triangle and a second planar triangle are respectively reconstructed;

[0009] The measured rudder wing is rotated by a certain angle around the vertical line through the rudder control instruction, and three laser spots formed by the single laser displacement sensor on the rotated rudder wing and three laser spots formed on the symmetric side are obtained; according to the three laser spots formed by the single laser displacement sensor on the rotated rudder wing and the three laser spots formed on the symmetric side, a third planar triangle and a fourth planar triangle are respectively reconstructed;

[0010] The normal vector included angle of the first planar triangle and the third planar triangle and the normal vector included angle of the second planar triangle and the fourth planar triangle are calculated to obtain the rudder deflection angle.

[0011] Further, the calculation of the normal vector included angle of the first planar triangle and the third planar triangle and the normal vector included angle of the second planar triangle and the fourth planar triangle specifically includes the following steps:

[0012] According to the laser triangulation principle, the laser spot space coordinate vectors X t i of different time points i are calculated.

[0013] The laser spot space coordinate vector X i is substituted into the space reconstruction plane equation to obtain the normal vector n 1i and n 2i of the reconstructed planar triangle, wherein i=0,1 is:

[0014] ;

[0015] ;

[0016] When i=0, the normal vectors of the first planar triangle and the third planar triangle are n 10 and n 20 respectively, and when i=1, the normal vectors of the second planar triangle and the fourth planar triangle are n 11 and n 21 respectively.

[0017] Then the normal vector included angle of the first planar triangle and the third planar triangle and the normal vector included angle of the second planar triangle and the fourth planar triangle are:

[0018] .

[0019] Further, the laser spot spatial coordinate vector X t i at different time is calculated according to the laser triangulation principle i , and specifically includes the following steps:

[0020] The precise piezoelectric actuator is moved to different cross sections through control instructions, and the linear displacement amount Δ L i of different cross sections relative to the initial reference position is recorded

[0021] The unilateral three-group laser light axis equation is: ;

[0022] Wherein, X=[ x , y , z ], A=[ a , b , c ], B=[ d , e , f ], a , b , c , d , e , f are the coefficients of the laser beam spatial straight line equation respectively

[0023] According to the laser triangulation principle, the relationship between the different time difference Δ t i and the linear displacement amount Δ L i is obtained: ;

[0024] The relationship between the different time difference Δ t i and the linear displacement amount Δ L i is solved together with the unilateral three-group laser light axis equation, and the laser spot spatial coordinate vector X t i at the corresponding time is obtained i .

[0025] Further, according to the normal vector angle of the first plane triangle and the third plane triangle and the normal vector angle of the second plane triangle and the fourth plane triangle, the rudder wing deflection angle θ is obtained by using the difference type plane reconstruction principle as:

[0026] ;

[0027] Wherein, and These are the normal vector coefficients of the reconstructed planes on both sides of the rudder at different times.

[0028] Furthermore, by symmetrically arranging three sets of non-collinear laser displacement sensors on each side of the complex-shaped rudder, the three laser spots formed by the single-sided laser displacement sensor at the initial position of the rudder and the three laser spots on the symmetrical side are obtained.

[0029] Furthermore, it also includes symmetrically arranging three sets of non-collinear laser displacement sensors on each side of the rudder, and then using fiber optic collimators to calibrate each set of laser displacement sensors to be perpendicular to the plumb line, and ensuring that the laser beams of each set of laser displacement sensors are parallel to each other.

[0030] This invention also proposes a precision non-contact angle measurement device for complex-shaped surface rudders, comprising:

[0031] The acquisition module is used to acquire the three laser spots formed by the single-sided laser displacement sensor on the complex surface rudder and the three laser spots on its symmetrical side at the initial position of the complex surface rudder.

[0032] The first reconstruction module is used to reconstruct the first planar triangle and the second planar triangle based on the three laser spots formed by the single-sided laser displacement sensor on the complex surface rudder and the three laser spots formed on the symmetrical side at the initial stage.

[0033] The second reconstruction module is used to rotate the measured rudder wing around the vertical line by a certain angle through servo control commands to obtain three laser spots formed by the single-sided laser displacement sensor at the position of the rudder wing after rotation and three laser spots on the symmetrical side; and to reconstruct the third planar triangle and the fourth planar triangle according to the three laser spots formed by the single-sided laser displacement sensor at the position of the rudder wing after rotation and the three laser spots on the symmetrical side respectively.

[0034] The calculation module is used to obtain the rudder deflection angle by calculating the angle between the normal vectors of the first and third planar triangles and the angle between the normal vectors of the second and fourth planar triangles.

[0035] This invention provides a method for precise non-contact angle measurement of complex-shaped surface rudders, which has the following advantages:

[0036] The present application realizes non-contact measurement of the deflection angle of the complex profile rudder wing based on the differential plane reconstruction principle by acquiring three laser spots formed by the complex profile rudder wing on one side of the laser displacement sensor and three laser spots on the symmetric side, respectively reconstructing the plane triangle before and after the rotation of each side of the rudder wing, which not only solves the technical limitations of the existing indirect contact angle measurement of the complex profile rudder wing of the guided projectile, such as low test efficiency, poor precision, and visual field obstruction and data loss based on visual measurement, but also realizes efficient and accurate measurement of the small rotation angle of the rudder wing, thereby providing technical support for precise attack of the guided projectile and error compensation of the rudder wing rotation closed loop / half closed loop. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 A flowchart of the complex profile rudder wing precision non-contact angle measurement method based on the differential plane reconstruction principle in the embodiment of the present application is shown in

[0038] Figure 2 A schematic diagram of the arrangement of the differential multi-group non-collinear laser displacement sensors in the angle measurement device of the measured rudder and the typical complex profile rudder wing in the embodiment of the present application is shown in

[0039] Figure 3 A schematic diagram of the principle of obtaining the space equation of the optical axis of the measurement laser displacement sensor by using the precision piezoelectric actuator in the embodiment of the present application is shown in

[0040] Figure 4 A schematic diagram of the principle of the triangular displacement measurement based on the laser displacement sensor in the embodiment of the present application is shown in

[0041] Figure 5 A schematic diagram of the spot reconstruction plane principle of the differential laser displacement sensor for the complex profile rudder wing angle measurement in the embodiment of the present application is shown in

[0042] Figure 6 A schematic diagram of the rudder wing precision non-contact deflection angle measurement method based on the differential plane reconstruction principle in the embodiment of the present application is shown in DETAILED DESCRIPTION

[0043] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments.

[0044] The present application proposes a complex profile rudder wing precision non-contact angle measurement method, as shown in Figure 1 The specific steps include the following steps:

[0045] S1. Arrange three sets of non-collinear laser displacement sensors symmetrically. Each set of sensors is collimated and perpendicular to the plumb line, while maintaining the parallelism of the laser beams. A schematic diagram of the arrangement of multiple sets of non-collinear laser displacement sensors is shown below. Figure 2 As shown.

[0046] S2. Using a high-precision linear motion platform such as a precision piezoelectric actuator, the measuring optical axes of the three sets of laser displacement sensors on each side are calibrated. Control commands are then used to move the precision piezoelectric actuator to different cross-sections. i ( i =1, 2, 3, ..., n), recording the linear displacement Δ of different sections relative to the initial reference position. L i ( i = 1, 2, 3, ..., n).

[0047] S3. Based on the principle of laser triangulation, calculate the values ​​at different times. t i The spatial coordinate vector X of the laser spot i .

[0048] S4. The servo motor is vertically arranged inside the complex-shaped rudder wing angle measuring device to ensure that the initial position of the rudder wing (denoted as M) is within the measurement range of the differential laser displacement sensor.

[0049] S5, The three laser spots formed by the single-sided laser displacement sensor at position M on the complex-shaped rudder are A 10 B 10 C 10 Then the laser spots on the symmetrical sides are A 11 B 11 C 11 Reconstruct the planar triangle ΔA respectively 10 B 10 C 10 With ΔA 11 B 11 C 11 .

[0050] S6. Rotate the tested rudder around the vertical line using servo control commands. θ The location is recorded as N, where the laser spot formed by the single-sided laser displacement sensor at location N is A. 20 B 20 C 20 Then the laser spots on the symmetrical sides are A 21 B 21 C 21 Reconstruct the planar triangle ΔA respectively 20 B 20 C 20 With ΔA 21B 21 C 21 .

[0051] S7、respectively define the reconstructed plane triangle ΔA 10 B 10 C 10 and ΔA 20 B 20 C 20 The normal vector of the plane triangle ΔA 10 , n 20 , the normal vector of the plane triangle ΔA 11 B 11 C 11 and ΔA 21 B 21 C 21 The normal vector of the plane triangle ΔA 11 , n 21 , the normal vector of the plane triangle ΔA i The angle between the normal vectors is:

[0052] (1)

[0053] The rudder wing deflection angle θ is:

[0054] (2)

[0055] Referring to Figure 3 and Figure 4 , the unilateral three sets of laser optical axis equation are:

[0056] (3)

[0057] In the formula: X=[ x , y , z ], A=[ a , b , c ], B=[ d , e , f ]; a , b , c , d , e , f The coefficients of the laser beam space straight line equation respectively.

[0058] According to the principle of laser triangulation, the laser sends laser through the focusing lens, the incident light acts on the measurement point of the measured surface, and the reflected light acts on the photosensitive point of the CCD receiver through the receiving lens, as shown in Figure 4 The time difference Δ t i (=t i-0) and the linear displacement amount Δ L i satisfying the following formula:

[0059] (4)

[0060] And by solving the formula (3) and (4) simultaneously, the laser spot spatial coordinate vector X t i at the corresponding time is obtained. i ;

[0061] Referring to Figure 5 and Figure 6 , the measurement of the laser spot spatial coordinates described in the present application is substituted into the spatial reconstruction plane equation:

[0062] (5)

[0063] The normal vectors n 1i and n 2i (i=0,1) of the reconstructed plane triangle can be expressed as:

[0064] (6)

[0065] (7)

[0066] wherein, respectively correspond to the A1i, B1i, Ci1 position points.

[0067] That is, the rudder wing deflection angle measured according to the differential plane reconstruction principle is:

[0068] (8)

[0069] wherein, and are the normal vector coefficients of the reconstructed planes on both sides of the rudder wing at different times, respectively.

[0070] Embodiment

[0071] This embodiment provides a non-contact angle measurement method based on the differential plane reconstruction principle for a non-symmetrical curvature complex surface rudder wing of a certain type of guided shell. The specific test steps are as follows:

[0072] S1, arrange each side laser displacement sensor according to not less than three groups of non-collinear symmetry (select three groups for calculation), the minimum spacing is better than the rudder wing thickness (4mm), and use the optical fiber collimator to correct each group of laser displacement sensors respectively perpendicular to the plumb surface, and keep the laser beams parallel to each other.

[0073] S2, using a high-precision linear motion platform (stroke > 4mm) such as a precision piezoelectric actuator, taking a single-sided three-group laser displacement sensor as an example, the one-dimensional relative displacement increment data is calibrated to obtain the measurement optical axis space equation X i The specific operation process includes: (1) recording the initial position and time of the precision piezoelectric actuator; (2) moving the precision piezoelectric actuator to not less than three cross-section positions i (i = 1, 2 and 3) through voltage control instructions, recording the linear displacement amount ΔL i (1mm, 1.2mm and 2.7mm) of different cross-sections relative to the initial reference position;

[0074] S3, by least squares fitting of the spatial coordinates of the measurement spot positions of different cross-sections, the single-sided three-group laser displacement sensor coordinate parameter matrix.

[0075] (9)

[0076] Similarly, the coordinate parameter matrix of the three-group laser displacement sensor on the symmetric side is:

[0077] (10)

[0078] S4, the rudder is vertically arranged in the complex profile rudder wing angle measurement device, and the initial position (marked as M) of the rudder wing is located in the measurement range of the differential laser displacement sensor.

[0079] S5, the single-sided laser displacement sensor at position M forms three laser spots A 10 , B 10 , C 10 on the complex profile rudder wing, then the laser spots on the symmetric side are A 11 , B 11 , C 11 , respectively, and the plane triangles ΔA 10 B 10 C 10 and ΔA 11 B 11 C 11 are reconstructed.

[0080] S6, through the rudder control instruction, the measured rudder wing is rotated θ around the plumb line, and the laser spots A 20 , B 20 , C 20 formed by the single-sided laser displacement sensor at position N are recorded, then the laser spots on the symmetric side are A 21 , B 21 , C 21 , respectively, and the plane triangles ΔA 20 B 20 C20 with ΔA 21 B 21 C 21 ;

[0081] S7, calculate the rudder wing deflection from position M to position N, the relative displacement value of the single-sided laser displacement sensor (0.040mm, 0.038mm, 0.031mm), and the relative displacement value of the symmetrical laser displacement sensor (0.034mm, 0.029mm, 0.027mm) is obtained.

[0082] S8, combine formulas (9) and (10), and substitute the laser spot relative displacement value into the reconstruction plane space equation, and obtain its normal vector n 1i and n 2i (i=0, 1), at this time the rudder wing deflection angle is 1.804°.

[0083] Referring to Figures 1 to 6 The complex surface rudder wing precision non-contact angle measurement method based on the differential plane reconstruction principle provided by the application can realize non-contact measurement of the deflection angle of the complex surface rudder wing based on the differential plane reconstruction principle through the symmetrical arrangement of multiple groups of laser displacement sensors, can not only solve the technical limitations of low test efficiency, poor precision, visual field obstruction, data loss and the like of the existing contact indirect deflection angle measurement of the complex surface rudder wing of a guided shell, but also can efficiently and accurately realize accurate measurement of the small deflection angle of the rudder wing, and provide technical support for precise attack of the guided shell and rudder wing deflection closed loop / half closed loop error compensation. In addition, the instrument and equipment required by the method are relatively simple to build, can realize non-contact measurement of the continuous deflection angle of the complex surface rudder wing, are easy to operate, and are strong in practicality.

[0084] Based on the above inventive concept, the application further provides a complex surface rudder wing precision non-contact angle measurement device, comprising:

[0085] The acquisition module is configured to acquire three laser spots formed by the single-sided laser displacement sensor at the initial position of the complex surface rudder wing and three laser spots on the symmetrical side.

[0086] The first reconstruction module is configured to reconstruct a first plane triangle and a second plane triangle according to the three laser spots formed by the single-sided laser displacement sensor at the initial position of the complex surface rudder wing and the three laser spots on the symmetrical side.

[0087] The second reconstruction module is configured to make the rudder wing rotate around the vertical line by a certain angle through the rudder control instruction, so as to obtain three laser spots formed by the position of the single-side laser displacement sensor on the rotated rudder wing and three laser spots on the symmetric side; and reconstruct a third plane triangle and a fourth plane triangle according to the three laser spots formed by the position of the single-side laser displacement sensor on the rotated rudder wing and the three laser spots on the symmetric side respectively.

[0088] The calculation module is configured to calculate the included angle of the normal vector of the first plane triangle and the third plane triangle and the included angle of the normal vector of the second plane triangle and the fourth plane triangle, so as to obtain the rudder wing deflection angle.

[0089] The above is only the preferred specific embodiment of the present application, but the protection scope of the present application is not limited to this. Any person skilled in the art can make equivalent replacements or changes according to the technical solution and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered in the protection scope of the present application.

Claims

1. A method for precision non-contact angle measurement of complex profile rudder wings, characterized in that, The method comprises the following steps: Three groups of non-collinear laser displacement sensors are symmetrically arranged on each side of the complex surface rudder wing, and each group of laser displacement sensors is respectively corrected to be perpendicular to the plumb line by using a fiber collimator, and the laser beams of each group of laser displacement sensors are parallel to each other, so that three laser spots formed by the single-sided laser displacement sensors at the initial position of the complex surface rudder wing and three laser spots on the symmetric side of the complex surface rudder wing are obtained; A first plane triangle and a second plane triangle are respectively reconstructed according to the three laser spots formed by the single-sided laser displacement sensors at the initial position of the complex surface rudder wing and the three laser spots on the symmetric side of the complex surface rudder wing; The measured rudder wing is rotated by a certain angle around the plumb line through a rudder control instruction, three laser spots formed by the single-sided laser displacement sensors at the position of the rudder wing after rotation and three laser spots on the symmetric side of the rudder wing after rotation are obtained, and a third plane triangle and a fourth plane triangle are respectively reconstructed according to the three laser spots formed by the single-sided laser displacement sensors at the position of the rudder wing after rotation and the three laser spots on the symmetric side of the rudder wing after rotation; The normal vector included angle of the first plane triangle and the third plane triangle and the normal vector included angle of the second plane triangle and the fourth plane triangle are calculated, and a rudder wing deflection angle is obtained.

2. A method for precision non-contact angle measurement of a complex profile rudder wing according to claim 1, characterized in that, The calculation of the normal vector included angle of the first plane triangle and the third plane triangle and the normal vector included angle of the second plane triangle and the fourth plane triangle specifically comprises the following steps: According to the principle of laser triangulation, the spatial coordinate vectors X of the laser spot at different times are calculated t i i ;​ Let the laser spot spatial coordinate vector be X i Substitute the spatial reconstruction plane equation , get the normal vector n of the reconstruction plane triangle 1i and n 2i , where i = 0, 1 is: ； ； wherein, when i = 0, the normal vectors of the first and third planar triangles are obtained as n 10 , n 20 , respectively, when i = 1, the normal vectors of the second and fourth planar triangles are obtained as n 11 , n 21 , respectively; The normal vector included angle of the first plane triangle and the third plane triangle and the normal vector included angle of the second plane triangle and the fourth plane triangle are: 。 3. A method of precision non-contact angle measurement of a complex profile rudder wing according to claim 2, characterized in that, The spatial coordinates vector X of the laser spot at different time points is calculated according to the laser triangulation principle t i i , and specifically comprises the following steps:​ By controlling the command, the precision piezoelectric actuator is moved to different cross sections, and the linear displacement amount Δ of different cross sections relative to the initial reference position is recorded L i ; The unilateral three-group laser optical axis equation is: ; wherein X=[ x , y , z ], A=[ a , b , c ], B=[ d , e , f ], and a , b , c , d , e , f are coefficients of the spatial straight line equation of the laser beam, respectively. According to the principle of laser triangulation, the relationship between the different time difference Δ t i and the linear displacement amount Δ L i is obtained: ; The relationship between different time differences Δ t i and linear displacement amounts Δ L i is solved simultaneously with a unilateral three-group laser optical axis equation to obtain a laser spot spatial coordinate vector X t i at the corresponding moment i .

4. The method of claim 2, wherein the method is a precision non-contact angle measurement method for a complex profile rudder wing. According to the angle between the normal vectors of the first and third planar triangles and the angle between the normal vectors of the second and fourth planar triangles, the rudder wing deflection angle is obtained by using the differential planar reconstruction principle θ is: ； wherein and are the normal vector coefficients of the reconstruction plane at different times on both sides of the rudder wing.

5. A precision non-contact angle measurement device for complex contoured rudder wings, characterized in that, It comprises: An acquisition module is configured to symmetrically arrange three groups of non-collinear laser displacement sensors on each side of the complex surface rudder wing, correct each group of laser displacement sensors to be perpendicular to the plumb line by using a fiber collimator, and make the laser beams of each group of laser displacement sensors parallel to each other, so as to obtain three laser spots formed by the single-sided laser displacement sensors at the initial position of the complex surface rudder wing and three laser spots on the symmetric side of the complex surface rudder wing; A first reconstruction module is configured to respectively reconstruct a first plane triangle and a second plane triangle according to the three laser spots formed by the single-sided laser displacement sensors at the initial position of the complex surface rudder wing and the three laser spots on the symmetric side of the complex surface rudder wing; A second reconstruction module is configured to rotate the measured rudder wing by a certain angle around the plumb line through a rudder control instruction, obtain three laser spots formed by the single-sided laser displacement sensors at the position of the rudder wing after rotation and three laser spots on the symmetric side of the rudder wing after rotation, and respectively reconstruct a third plane triangle and a fourth plane triangle according to the three laser spots formed by the single-sided laser displacement sensors at the position of the rudder wing after rotation and the three laser spots on the symmetric side of the rudder wing after rotation; A calculation module is configured to calculate the normal vector included angle of the first plane triangle and the third plane triangle and the normal vector included angle of the second plane triangle and the fourth plane triangle, and obtain a rudder wing deflection angle.

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