An automated precision alignment method and system for the low-pressure compressor long shaft of an aero-engine

Abstract

The present invention relates to the technical field of aero-engine assembly, and specifically relates to a precise and efficient automatic centering method and system during the assembly process of a low-pressure turbine rotor assembly of an aero-engine. By calibrating the installed binocular camera subsystem, the imaging characteristics of multiple positioning marker points on the engine are obtained. After rough centering, the data of the positioning features are obtained in real time by the binocular camera, the relative position and attitude deviation are calculated, and the large robotic arm and the multi-degree-of-freedom precision pose adjustment platform are controlled to perform precise movements, so as to achieve the centering task of the low-pressure turbine long axis relative to the aero-engine assembly. The technical solution of the present application can greatly improve the assembly efficiency, automation level and operation reliability of the low-pressure turbine rotor assembly of an aero-engine.

Description

Technical Field

[0001] The present invention relates to the technical field of aero-engine assembly, and particularly relates to a precise and efficient automatic centering method and system for the assembly process of a low-pressure turbine rotor assembly of an aero-engine. Background Art

[0002] The low-pressure turbine rotor assembly is a key part of an aero-engine. Since the low-pressure turbine rotor assembly includes a long-axis component that almost runs through the front and back of the aero-engine, its assembly process is a task with complex component structures, high precision requirements, and great technical difficulties. Traditionally, to insert the low-pressure turbine shaft through the center of the high-pressure rotor of the aero-engine and accurately connect it to the support assembly of the fan assembly, it is necessary to use the method of manual observation or laser tracker debugging and alignment to ensure the centering of the long-axis component of the low-pressure turbine in the engine center during the assembly operation. Since both manual careful observation and laser tracker alignment require a long working debugging cycle to avoid problems such as connection damage caused by excessive alignment errors, the assembly centering operation efficiency of the low-pressure turbine shaft is generally low. In recent years, the demand for high-efficiency and reliable assembly of aero-engines at home and abroad has become increasingly strong. Therefore, there is an urgent need to develop a new type of automated and intelligent technical means to solve the problem of efficient centering of the long-axis component during the assembly process of the low-pressure turbine rotor assembly. Summary of the Invention

[0003] In view of the above deficiencies of the prior art, the present invention proposes a technical solution for automatic precision centering of the low-pressure turbine long axis during the overall assembly process of an aero-engine.

[0004] The present invention proposes an automatic precision centering system for the low-pressure turbine long axis, and the system includes:

[0005] A large robotic arm for large-angle rotation and precise controllable up-and-down movement to hoist the low-pressure turbine rotor assembly of the aero-engine.

[0006] A multi-degree-of-freedom precision posture adjustment platform is installed on the large robotic arm and is connected to the low-pressure turbine rotor assembly through a low-pressure turbine rotor assembly installation tooling, and can perform multi-degree-of-freedom precision movement adjustment to achieve the precision centering task of the low-pressure turbine long axis during the engine assembly process.

[0007] A low-pressure turbine long-axis component installation tooling that can precisely position and clamp the low-pressure turbine long-axis component and install it on the multi-degree-of-freedom precision posture adjustment platform.

[0008] A binocular camera subsystem is fixedly connected to the multi-degree-of-freedom precision posture adjustment platform and always maintains an accurate relative pose relationship with the low-pressure turbine long-axis component.

[0009] A data processing and operation control subsystem that can receive the image data of the binocular camera subsystem, process the data through a software program, calculate the pose adjustment parameters of the multi-degree-of-freedom precision pose adjustment platform, and send control instructions.

[0010] The present invention also proposes an alignment method for a low-vortex long-axis automatic precision alignment system, and the method includes:

[0011] Step 1: Calibrate the installed binocular camera subsystem to determine the imaging characteristics of multiple positioning marker points on the engine to be detected by the camera at a given distance under ideal alignment conditions.

[0012] Step 2: Make the large robotic arm and the multi-degree-of-freedom precision pose adjustment platform enter the initial operation state, and complete the rough alignment task of the low-vortex long axis relative to the aero-engine assembly.

[0013] Step 3: Use the binocular camera subsystem to image multiple positioning marker points on the aero-engine assembly.

[0014] Step 4: Send the image data of the binocular camera subsystem and the distance data from the specified end face of the engine assembly to the data processing and operation control subsystem. Process the data through a software program to calculate the eccentricity and angular difference of the low-vortex rotor assembly relative to the engine assembly, and then calculate the pose adjustment parameters of the multi-degree-of-freedom precision pose adjustment platform based on the eccentricity and angular difference, and control the multi-degree-of-freedom precision pose adjustment platform to move to achieve precise alignment.

[0015] Step 5: Operate the robotic arm to slowly lower, so that the low-pressure turbine shaft gradually inserts and passes through the center of the high-pressure rotor of the aero-engine and accurately docks with the support assembly of the fan unit.

[0016] According to an embodiment of the present invention, the data processing program of the data processing and operation control subsystem includes a key algorithm for processing the image data of the binocular camera subsystem to calculate the eccentricity and angular difference of the low-vortex rotor assembly relative to the engine assembly. Specifically, it includes the following steps:

[0017] Step 4.1: There is an ideal alignment condition imaging database in the data processing program, and the imaging data of the positioning marker points corresponding to a given distance under ideal alignment conditions are stored in the database;

[0018] Step 4.2: Extract the current imaging data of multiple positioning marker points on the aero-engine assembly by the binocular camera system, calculate the coordinates of these positioning marker points, and calculate the area of the figure At formed by these positioning points;

[0019] Step 4.3: Calculate the ratio data of the area At of the graph and the area Az of the standard graph in the imaging database and take the square root. Taking the nominal distance data corresponding to the standard graph Az in the imaging database as a reference, deduce the actual distance between the current imaging position and the specified end face on the engine assembly.

[0020] Step 4.4: Compare the current imaging graph and the coordinate data of the positioning marker points with the standard graph and the coordinate data of the positioning marker points in the imaging database, and calculate the eccentricity distance and angular difference between the current position of the low-pressure turbine shaft and the ideal centering position.

[0021] In addition, the present application also provides a computing device and a computer-readable storage medium for the automatic precision centering method of the low-pressure turbine long shaft, which are characterized by including a processor and a memory. The memory stores instructions that can be executed by the processor to implement the above automatic precision centering method of the low-pressure turbine long shaft. When the computer-executable instructions are called and executed by the processor, the computer-executable instructions prompt the processor to implement the above automatic precision centering method of the low-pressure turbine long shaft.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention adopts a fully automated closed-loop control technical solution. By obtaining the data of the positioning features in real time through a binocular camera, calculating the relative position and attitude deviation, and controlling the large robotic arm and the multi-degree-of-freedom precision posture adjustment platform to perform precise movements, the centering task of the low-pressure turbine long shaft relative to the aero-engine assembly is realized, which can greatly improve the assembly efficiency, automation level and operation reliability of the aero-engine low-pressure turbine rotor assembly. Description of the Drawings

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, 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 disclosure. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0024] Figure 1 Automatic precision centering system structure of the low-pressure turbine long shaft. Detailed Embodiments

[0025] The present invention will be further described in detail below with reference to the drawings:

[0026] Combined with the attached Figure 1 , the automatic precision centering system of the low-pressure turbine long shaft proposed by the present invention includes: a large robotic arm (1), a multi-degree-of-freedom precision posture adjustment platform (2), a low-pressure turbine long shaft component installation tooling (3), a binocular camera subsystem (4), a data processing and operation control subsystem (5), and multiple positioning marker points (6) on the engine.

[0027] Among them, the large robotic arm can perform large-angle rotation and precise up-and-down controllable movement, and is used for hoisting the low-pressure turbine rotor assembly of an aeroengine.

[0028] The multi-degree-of-freedom precision pose adjustment platform is installed on the large robotic arm and is connected to the low-pressure turbine rotor assembly through the installation tooling for the low-vortex rotor assembly. It can perform multi-degree-of-freedom precision movement adjustment and achieve the precision centering task of the low-pressure turbine long shaft during the engine assembly process.

[0029] The installation tooling for the low-vortex long shaft assembly can precisely position and clamp the low-vortex long shaft assembly and install it on the multi-degree-of-freedom precision pose adjustment platform.

[0030] The binocular camera subsystem is fixedly connected to the multi-degree-of-freedom precision pose adjustment platform and always maintains an accurate relative pose relationship with the low-vortex long shaft assembly.

[0031] The data processing and operation control subsystem can receive the image data of the binocular camera subsystem, perform data processing through software programs, calculate the pose adjustment parameters of the multi-degree-of-freedom precision pose adjustment platform, and send control instructions.

[0032] The present invention also proposes a method for automatic precision centering of the low-vortex long shaft. The method includes:

[0033] Step 1: Calibrate the installed binocular camera subsystem to determine the imaging characteristics of multiple positioning marker points on the engine to be detected by the camera at a given distance under ideal centering conditions.

[0034] Step 2: Make the large robotic arm and the multi-degree-of-freedom precision pose adjustment platform enter the initial operation state, and complete the rough centering task of the low-vortex long shaft relative to the aeroengine assembly.

[0035] Step 3: Use the binocular camera subsystem to image multiple positioning marker points on the aeroengine assembly.

[0036] Step 4: Send the image data of the binocular camera subsystem and the distance data from the specified end face on the engine assembly to the data processing and operation control subsystem. Perform data processing through software programs, calculate the eccentricity and angular difference of the low-vortex rotor assembly relative to the engine assembly, and then calculate the pose adjustment parameters of the multi-degree-of-freedom precision pose adjustment platform based on the eccentricity and angular difference and control the multi-degree-of-freedom precision pose adjustment platform to move to achieve precision centering.

[0037] Step 5: Operate the robotic arm to slowly descend so that the low-pressure turbine shaft gradually inserts and passes through the center of the high-pressure rotor of the aeroengine and accurately docks with the support assembly of the fan unit.

[0038] According to an embodiment of the present invention, the data processing program of the data processing and operation control subsystem includes a key algorithm for processing the image data of the binocular camera subsystem to calculate the eccentricity and angular difference of the low-pressure turbine rotor assembly relative to the engine assembly. Specifically, it includes the following steps:

[0039] Step 4.1: The data processing program includes an ideal centering condition imaging database, which stores the imaging data of the positioning marker points corresponding to a given distance under the ideal centering condition;

[0040] Step 4.2: Extract the current imaging data of multiple positioning marker points on the aero-engine assembly by the binocular camera system, calculate the coordinates of these positioning marker points, and calculate the area of the figure At formed by these positioning points;

[0041] Step 4.3: Calculate the ratio data of the area of the figure At to the area of the standard figure Az in the imaging database and take the square root. Taking the nominal distance data corresponding to the standard figure Az in the imaging database as a reference, deduce the actual distance between the current imaging position and the specified end face on the engine assembly;

[0042] Step 4.4: Compare the current imaging figure and the positioning marker point coordinate data with the standard figure and the positioning marker point coordinate data in the imaging database, and calculate the eccentricity distance and angular difference between the current position of the low-pressure turbine shaft and the ideal centering position.

[0043] As mentioned above, it is only the specific embodiment of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present disclosure should be covered within the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be subject to the protection scope of the claims.

Claims

1. A centering method for a low-vortex long-axis automatic precision centering system, the method comprising: Step 1: Calibrate the installed binocular camera subsystem to determine the imaging characteristics of multiple positioning marker points on the engine to be detected by the camera at a given distance under ideal centering conditions; Step 2: Make the large robotic arm and the multi-degree-of-freedom precision pose adjustment platform enter the initial operation state, and complete the rough centering task of the low-vortex long axis relative to the aero-engine assembly; Step 3: Use the binocular camera subsystem to image multiple positioning marker points on the aero-engine assembly; Step 4: Send the image data of the binocular camera subsystem and the distance data from the specified end face on the engine assembly to the data processing and operation control subsystem, calculate the eccentricity and angular difference of the low-vortex rotor assembly relative to the engine assembly, and calculate the pose adjustment parameters of the multi-degree-of-freedom precision pose adjustment platform based on the eccentricity and angular difference and control the multi-degree-of-freedom precision pose adjustment platform to move to achieve precise centering; Wherein In step 4, the image data of the binocular camera subsystem is processed to calculate the eccentricity and angular difference of the low-vortex rotor assembly relative to the engine assembly, which specifically includes the following steps: Step 4.1: The data processing program includes an ideal centering condition imaging database, and the database stores the imaging data of the positioning marker points corresponding to the given distance under ideal centering conditions; Step 4.2: Extract the current imaging data of multiple positioning marker points on the aero-engine assembly by the binocular camera system, calculate the coordinates of these positioning marker points, and calculate the area of the figure At formed by these positioning points; Step 4.3: Calculate the ratio data of the area of the figure At to the area of the standard figure Az in the imaging database and take the square root, and infer the actual distance between the current imaging position and the specified end face on the engine assembly with reference to the nominal distance data corresponding to the standard figure Az in the imaging database; Step 4.4: Compare the current imaging figure and the positioning marker point coordinate data with the standard figure and the positioning marker point coordinate data in the imaging database, and calculate the eccentricity distance and angular difference between the current position of the low-pressure turbine shaft and the ideal centering position.

2. The centering method of the low-vortex long-axis automatic precision centering system according to claim 1, characterized in that The method further includes: Step 5: Operate the robotic arm to slowly lower, so that the low-pressure turbine shaft gradually inserts and passes through the center of the high-pressure rotor of the aero-engine and accurately docks with the support assembly of the fan unit.

3. A low-vortex major axis automatic precision centering system, comprising: A large robotic arm (1), a multi-degree-of-freedom precision pose adjustment platform (2), a low-vortex long-axis component installation tooling (3), a binocular camera subsystem (4), a data processing and operation control subsystem (5), and multiple positioning marker points on the engine (6), this system is used to execute the centering method of the low-vortex long-axis automatic precision centering system according to any one of the above claims 1-2.

4. The low-vortex long-axis automatic precision centering system according to claim 3, characterized in that: The large robotic arm can perform large-angle rotation and up-and-down precision controllable movement, and is used for hoisting the low-pressure turbine rotor assembly of the aero-engine; The multi-degree-of-freedom precision pose adjustment platform is installed on a large robotic arm and is connected to the low-pressure turbine rotor assembly through the low-vortex rotor assembly installation tooling. It can perform precision motion adjustment in multiple degrees of freedom and achieve the precision centering task of the low-pressure turbine long shaft during the engine assembly process; The low-vortex long shaft assembly installation tooling can precisely position and clamp the low-vortex long shaft assembly and install it on the multi-degree-of-freedom precision pose adjustment platform; The binocular camera subsystem is fixedly connected to the multi-degree-of-freedom precision pose adjustment platform and always maintains an accurate relative pose relationship with the low-vortex long shaft assembly; The data processing and operation control subsystem can receive the image data of the binocular camera subsystem, calculate the pose adjustment parameters of the multi-degree-of-freedom precision pose adjustment platform and send control instructions.

5. A computer device, characterized in that, It includes a processor and a memory. The memory stores computer-executable instructions that can be executed by the processor. The processor executes the computer-executable instructions to implement the method described in any one of claims 1-2.

6. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions. When the computer-executable instructions are called and executed by the processor, the computer-executable instructions cause the processor to implement the method described in any one of claims 1-2.

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