Attitude and orbit control engine jet pipe thrust line measuring method

Abstract

The invention discloses an attitude and orbit control engine nozzle thrust line measurement method, which comprises the following steps of: measuring the central axis of each nozzle by adopting a three-coordinate or laser three-dimensional scanning measurement mode, and selecting two points on the axis as measurement data of the axis; calculating position coordinate values of intersection points of extension lines of thrust axes of all the spray pipes and the center line of the engine; comparing with a cube of which the design requirement value t is the side length; and judging by taking whether the coordinate value is within the range of a cube with t as the side length as a qualification judgment standard to finish the measurement of the thrust line. According to the attitude and orbit control engine jet pipe thrust line measurement method, the measurement original point is set during measurement, the subsequent space coordinate value conversion is simpler and more convenient, the u value is determined according to the design size, the design basis is considered, the measurement data better conform to the actual working condition, the method is suitable for attitude and orbit control engine jet pipe thrust line measurement of multiple jet pipes, and the measurement efficiency is improved. The problems that multiple nozzle attitude and orbit control engine nozzle thrust lines are difficult to measure and axis intersection cannot be judged are solved.

Description

Technical Field

[0001] The invention relates to the field of aerospace engines, and in particular to a method for measuring the thrust line of a nozzle of an attitude and orbit control engine. Background Art

[0002] The engine of aerospace equipment will inevitably produce certain errors from the design during manufacturing. If the error is within the allowable range, the engine can be installed normally. However, due to various accumulated errors and various installation errors, the installed engine has deflection and lateral displacement from the pre-designed attitude, causing the actual thrust line to be unable to coincide with the designed thrust line, resulting in a deflection moment during the operation of the engine, which directly affects its attitude control during flight. Therefore, for aerospace equipment with high requirements for speed, work efficiency and load capacity, obtaining accurate engine nozzle thrust line is a very important measurement work. The thrust line measurement of traditional aerospace equipment engines generally adopts the special point measurement method. This method is to set special measurement points on the equipment structure and engine during the design and manufacturing process of the equipment, measure the coordinates of these special points by a level measuring instrument, and then obtain the thrust line equation and the theoretical error range of the special measurement points after a series of complex calculations. Because this measurement method is based on actual calibrated special points for calculation, it has large errors in itself. At the same time, the aerospace equipment and theodolite need to be leveled during use. Once vibration or movement of the instrument or equipment occurs, it needs to be leveled again. It is time-consuming, inefficient, and has large errors. In addition, the calculated results cannot directly guide the correction and installation of the engine thrust line.

[0003] The attitude and orbit control engine is composed of a combustion chamber, propellant, nozzle and other structures. Multiple evenly distributed nozzles are arranged in the radial position of the engine. The engine attitude is controlled by coordinating and working together. The spatial position of the nozzle thrust line directly affects the attitude control. Once the thrust line deviates from the design requirements, the engine attitude adjustment cannot be achieved. Therefore, it is necessary to measure the thrust line of the assembled nozzle to determine whether it meets the design requirements. Summary of the invention

[0004] The technical problem solved by the present invention is: the selection of the nozzle thrust line measurement surface and the measurement reference in the three-dimensional space state and the thrust line fitting, and finally judging whether the thrust line is qualified through calculation.

[0005] The technical solution of the present invention is: a method for measuring the thrust line of the nozzle of an attitude and orbit control engine, which is suitable for measuring the spatial position of the thrust line of the nozzle of an attitude and orbit control engine and a qualified judgment method, and the steps are as follows:

[0006] S1. Use three-coordinate or laser three-dimensional scanning measurement to measure the central axis of each nozzle, and select two points on the axis as the measurement data of the axis;

[0007] S2. Calculate the coordinates of the intersection of the extended line of each nozzle thrust axis and the engine centerline;

[0008] S3, compared with the cube with the design requirement value t as the side length;

[0009] S4. Whether the coordinate value is within the range of a cube with a side length of t is used as the qualification criterion for judgment.

[0010] Preferably, in step S1, the measuring surface during the three-coordinate or laser three-dimensional scanning measurement is selected as a metal inner hole and outer circle, and there is no detachable structure between the two measuring surface rings to reduce the measurement error amplification effect, so that the two rings can represent the thrust line position of the nozzle.

[0011] Preferably, in step S1, the engine axis passes through the measurement origin O(0, 0, 0), the measurement origin is the intersection of the engine axis and the butt end face, and the theoretical value of the tube thrust line plane distance measurement origin is u, and the theoretical value U is determined according to the size of the part design drawing.

[0012] Preferably, in step S2, the calculation of the intersection position coordinate value is characterized in that: the method for calculating the intersection position coordinate value of the extension line of each nozzle thrust axis and the engine center line is: assuming that the coordinate values ​​of two points of a nozzle thrust line are P1 (X1, Y1, Z1), P2 (X2, Y2, Z2).

[0013] Preferably, in step S2, it is assumed that the extension line of the G1 nozzle thrust line intersects the Y0Z plane, then the intersection position of the extension line of the G1 thrust axis line and the Y0Z plane is: G1 =0;

[0014] Preferably, in step S2, it is assumed that the extension line of the G2 nozzle thrust line intersects the X0Z plane, and the intersection position of the extension line of the G2 thrust axis line and the X0Z plane is: y G2 =0;

[0015] Preferably, in step S2, it is assumed that the extension line of the G3 nozzle thrust line intersects the Y0Z plane, and the intersection position of the G3 thrust axis extension line and the Y0Z plane is: X G3 =0;

[0016] Preferably, in step S2, it is assumed that the extension line of the thrust line of the G4 nozzle intersects the X0Z plane, and the intersection position of the extension line of the thrust axis of G4 and the X0Z plane is: yG4 =0;

[0017] Preferably, in steps S3 and S4, the basis for judging whether it is qualified is that if the intersection coordinates of the extension line of the nozzle thrust line and the Y0Z plane are Then qualified.

[0018] The advantages of the present invention over the prior art are: compared with the pure space 2 straight line distance calculation method, the measurement origin is set during measurement, making it easier to convert the subsequent space coordinate values, and the u value is determined according to the design size, taking into account the design benchmark, so that the measurement data is more in line with the actual working conditions. The measurement method provided by the present invention is applicable to the intersection distance between the thrust line of the nozzle of the attitude and orbit control engine of multiple nozzles and the axis line, solving the problem that the thrust line of the nozzle of the attitude and orbit control engine of multiple nozzles is difficult to measure and the intersection of the axis line cannot be determined. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of an attitude and orbit control engine nozzle according to a method for measuring the thrust line of an attitude and orbit control engine nozzle provided by the present invention;

[0020] Figure 2 It is an example diagram of the position of the nozzle thrust line of a method for measuring the nozzle thrust line of an attitude and orbit control engine provided by the present invention;

[0021] Figure 3 This is an example diagram of the intersection position of the nozzle thrust line and the engine axis of a method for measuring the nozzle thrust line of an attitude and orbit control engine provided by the present invention;

[0022] Figure 4 It is an example diagram of the nozzle thrust line of a method for measuring the nozzle thrust line of an attitude and orbit control engine provided by the present invention intersecting a cube with a side length of t=0.8 mm;

[0023] Markings in the figure:

[0024] 1-1, G3 nozzle thrust line, 1-2, G2 nozzle thrust line, 1-3, intersection of nozzle thrust line and engine axis, 1-4, engine axis, 1-5, G1 nozzle thrust line, 1-6, G4 nozzle thrust line; 2-1, G1 nozzle thrust line, 2-2, G2 nozzle thrust line, 2-3, G3 nozzle thrust line, 2-4, G4 nozzle thrust line, 2-5, engine axis; 3-1, G1 nozzle thrust line, 3-2, G2 nozzle thrust line, 3-3, G3 nozzle thrust line; 3-4, G4 nozzle thrust line, 3-5, engine axis, 3-6, cube; 4-1, thrust line.

[0025] Specific implementation methods

[0026] The technical solution of the present invention is: a method for measuring the thrust line of the nozzle of an attitude and orbit control engine, which is suitable for measuring the spatial position of the thrust line of the nozzle of an attitude and orbit control engine and a qualified judgment method, and the steps are as follows:

[0027] S1. Use three-coordinate or laser three-dimensional scanning measurement to measure the central axis of each nozzle, and select two points on the axis as the measurement data of the axis;

[0028] S2. Calculate the coordinates of the intersection of the extended line of each nozzle thrust axis and the engine centerline;

[0029] S3, compared with the cube with the design requirement value t as the side length;

[0030] S4. Whether the coordinate value is within the range of a cube with a side length of t is used as the qualification criterion for judgment.

[0031] Preferably, in step S1, the measuring surface during the three-coordinate or laser three-dimensional scanning measurement is selected as a metal inner hole and outer circle, and there is no detachable structure between the two measuring surface rings to reduce the measurement error amplification effect, so that the two rings can represent the thrust line position of the nozzle.

[0032] Preferably, in step S1, the engine axis passes through the measurement origin O(0, 0, 0), the measurement origin is the intersection of the engine axis and the butt end face, and the theoretical value of the tube thrust line plane distance measurement origin is u, and the theoretical value U is determined according to the size of the part design drawing.

[0033] Preferably, in step S2, the calculation of the intersection position coordinate value is characterized in that: the method for calculating the intersection position coordinate value of the extension line of each nozzle thrust axis and the engine center line is: assuming that the coordinate values ​​of two points of a nozzle thrust line are P1 (X1, Y1, Z1), P2 (X2, Y2, Z2).

[0034] Preferably, in step S2, it is assumed that the extension line of the G1 nozzle thrust line intersects the Y0Z plane, then the intersection position of the extension line of the G1 thrust axis line and the Y0Z plane is: G1 =0;

[0035] Preferably, in step S2, it is assumed that the extension line of the G2 nozzle thrust line intersects the X0Z plane, and the intersection position of the extension line of the G2 thrust axis line and the X0Z plane is: y G2 =0;

[0036] Preferably, in step S2, it is assumed that the extension line of the G3 nozzle thrust line intersects the Y0Z plane, and the intersection position of the G3 thrust axis extension line and the Y0Z plane is: X G3 =0;

[0037] Preferably, in step S2, it is assumed that the extension line of the thrust line of the G4 nozzle intersects the X0Z plane, and the intersection position of the extension line of the thrust axis of G4 and the X0Z plane is: y G4 =0;

[0038] Preferably, in steps S3 and S4, the basis for judging whether it is qualified is that if the intersection coordinates of the extension line of the nozzle thrust line and the Y0Z plane are Then qualified.

[0039] The following takes the thrust line measurement of a cross-shaped four-nozzle attitude and trajectory control engine as an example and further illustrates the technical solution of the present invention in conjunction with the accompanying drawings.

[0040] The present invention provides a method for measuring the thrust line of a nozzle of an attitude and orbit control engine, which is applicable to measuring and calculating the thrust line of a nozzle of an attitude and orbit control engine, and the steps are as follows:

[0041] S1, such as Figure 1 The attitude and orbit control engine nozzle thrust line measurement method is shown in the schematic diagram of the attitude and orbit control engine nozzle, including the thrust lines of the four nozzles, the engine axis and the intersection of the nozzle thrust line and the engine axis. Figure 2 This is an example diagram of the nozzle thrust line position of a method for measuring the nozzle thrust line of an attitude and orbit control engine according to the present invention.

[0042] like Figure 3 The intersection position of the nozzle thrust line and the engine axis of the attitude and orbit control engine nozzle thrust line measurement method is shown in the figure. Taking the thrust line measurement of a cross-shaped four-nozzle attitude and orbit control engine as an example, they are set as G1, G2, G3, and G4 nozzles respectively. The extension lines of the axes of the four orbit control nozzles should fall into a cube with the origin as the center and t=0.8mm as the side length. The theoretical value of the distance between the four nozzle thrust line planes and the measurement origin is u=-113.5. The coordinates of the axis measurement points of the thrust lines of each nozzle are shown in Table 1.

[0043] Table 1 Coordinate values ​​of thrust line axis of a certain part

[0044]

[0045] S2, such as Figure 4 The nozzle thrust line of the attitude and orbit control engine nozzle thrust line measurement method intersects with a cube with a side length of t = 0.8 mm as shown in the example figure. It is determined whether the extension line of the thrust line can intersect with the cube with a side length of t = 0.8 mm and the origin as the center, that is, whether the extension line is within the square range formed by a1, a2, c1, and c2. The angular deviation of the thrust line should be controlled within the range between points a1 and a2. If the above conditions are met, the thrust line is qualified.

[0046] Figure 4 In the figure, the thrust line is 133.5 mm away from the cube, while the distance between points a1 and a2 is 0.8 mm, a difference of 166.8 times. Therefore, the approximate thrust line is within the position range of b1 and b2.

[0047] S3. Calculate the coordinates of the intersection of the straight line connecting the two points on the thrust line and the plane passing through the origin.

[0048] The extension line of G1 nozzle thrust line intersects with Y0Z plane. The intersection position of G1 thrust axis extension line and Y0Z plane is: X G1 =0;

[0049] The extension line of the G2 nozzle thrust line intersects with the X0Z plane. The intersection position of the extension line of the G2 thrust axis line and the X0Z plane is: y G2 =0;

[0050] The extension line of G3 nozzle thrust line intersects with Y0Z plane. The intersection position of G3 thrust axis extension line and Y0Z plane is: X G3 =0;

[0051] The extension line of the G4 nozzle thrust line intersects with the X0Z plane. The intersection position of the G4 thrust axis extension line and the X0Z plane is: y G4 =0;

[0052] According to the above thrust line calculation method, the coordinates of the intersection point with the plane can be obtained as shown in Table 2:

[0053] Table 2 Intersection position of thrust line and plane

[0054]

[0055] The intersection points of S4, G1, G2, G3, G4 and their corresponding planes are all ≤ That is, it is less than or equal to 0.4mm, so the thrust lines of the four nozzles meet the design requirements.

[0056] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope of the technical solution of the present invention.

Claims

1. A method for measuring the thrust line of an attitude and orbit control engine nozzle, characterized in that: The specific steps of the method are as follows: S1. Use three-coordinate or laser three-dimensional scanning measurement to measure the central axis of each nozzle, and select two points on the axis as the measurement data of the engine axis; S2. Calculate the coordinates of the intersection of the extended line of each nozzle thrust axis and the engine centerline; S3, compared with the cube with the design requirement value t as the side length; S4. Whether the coordinate value is within the range of a cube with a side length of t is used as the qualification criterion for judgment.

2. The method for measuring the thrust line of the nozzle of an attitude and orbit control engine according to claim 1, characterized in that: In step S1, when three-coordinate or laser three-dimensional scanning measurement is performed, the measuring surface selects the metal inner hole and outer circle as the structure, and there is no detachable structure between the two measuring surface rings to reduce the measurement error amplification effect. The ring represents the thrust line position of the nozzle.

3. The method for measuring the thrust line of the nozzle of an attitude and orbit control engine according to claim 1, characterized in that: In step S1, the engine axis passes through the measurement origin O(0, 0, 0), and the measurement origin is the intersection of the engine axis and the docking end surface. The theoretical value of the nozzle thrust line plane distance measurement origin is set to u, and the theoretical value u is determined according to the size of the part design drawing.

4. The method for measuring the thrust line of the nozzle of an attitude and orbit control engine according to claim 1, characterized in that: In step S2, assuming that the coordinate values ​​of two points of a nozzle thrust line are P1 (X1, Y1, Z1), P2 (X2, Y2, Z2), and the extension line of the G1 nozzle thrust line intersects with the Y0Z plane, the intersection position of the extension line of the G1 thrust axis and the Y0Z plane is:

5. The method for measuring the thrust line of the nozzle of an attitude and orbit control engine according to claim 1, characterized in that: In step S2, the coordinate values ​​of two points of a nozzle thrust line are set to P1 (X1, Y1, Z1), P2 (X2, Y2, Z2), the extension line of the G2 nozzle thrust line intersects with the X0Z plane, and the intersection position of the extension line of the G2 thrust axis line and the X0Z plane is:

6. The method for measuring the thrust line of the nozzle of an attitude and orbit control engine according to claim 1, characterized in that: In step S2, the coordinate values ​​of two points on a nozzle thrust line are set to P1 (X1, Y1, Z1), P2 (X2, Y2, Z2), the extended line of the nozzle thrust line G3 intersects with the Y0Z plane, and the position of the intersection of the extended line of the thrust axis and the Y0Z plane G3 is:

7. The method for measuring the thrust line of the nozzle of an attitude and orbit control engine according to claim 1, characterized in that: In step S2, the coordinate values ​​of two points on a nozzle thrust line are set to P1 (X1, Y1, Z1), P2 (X2, Y2, Z2), the extension line of the nozzle thrust line G4 intersects with the X0Z plane, and the intersection position of the extension line of the thrust axis and the X0Z plane G4 is:

8. The method for measuring the thrust line of the nozzle of an attitude and orbit control engine according to claim 1, characterized in that: In step S4, whether the coordinate value is qualified is determined based on: Then qualified.

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