An engine profile automatic scanning detection system and method

Abstract

The application discloses an engine contour automatic scanning detection system and method, and belongs to the field of manufacturing geometric quantity measurement and detection. The application comprises a multi-vision measurement system, a line laser scanner with a spatial positioning device, a six-axis mechanical arm, an engine support platform with multiple spatial positioning targets, and control and data analysis software. The application realizes non-contact automatic scanning detection of the engine contour based on optics. The detection system of the application is mounted on the six-axis mechanical arm, can realize real-time compensation of the mechanical arm path, does not need to strictly control the relative position relationship between the six-axis mechanical arm and the measured aero-engine, realizes flexible automatic non-contact scanning detection of the large-area engine contour, reduces the cumulative error caused by continuous splicing during scanning measurement of the traditional handheld scanner through global splicing of the scanning data of the engine contour, improves the detection precision, shortens the detection period, and improves the detection efficiency.

Description

Technical Field

[0001] This invention relates to an automatic scanning and inspection system and method for engine outline, belonging to the field of geometric measurement and inspection in the manufacturing industry. Background Technology

[0002] Aero engines provide the power needed for aircraft flight. Their surfaces are covered with numerous pipes and critical components. Because aero engines operate in high-temperature, high-pressure, and high-frequency vibration environments, any deviation in the installation position of these components can jeopardize the engine's safety and reliability. Therefore, the inspection of the engine's external profile after assembly is crucial. Traditional inspection methods include contact measurement using clamps and non-contact measurement using handheld optical scanners. The former suffers from poor accuracy, while the latter suffers from low efficiency and complex pre- and post-processing. The automatic engine profile scanning device designed in this invention employs a non-contact measurement method, enabling rapid batch scanning of engine profiles. Utilizing a multi-view vision measurement system and an engine support platform, it can globally stitch the scanned data, reducing cumulative stitching errors caused by continuous stitching, improving inspection accuracy, shortening the inspection cycle, and increasing inspection efficiency. Summary of the Invention

[0003] Addressing the challenges of high-precision and high-efficiency inspection of aero-engine outlines, the main objective of this invention is to provide an automatic scanning and inspection system and method for engine outlines. Based on optical principles, this system enables non-contact, automated scanning and inspection of engine outlines. The inspection system is mounted on a six-axis robotic arm, allowing for real-time path compensation without requiring strict control of the relative position between the six-axis robotic arm and the tested aero-engine. This enables flexible, automated, non-contact scanning and inspection of a large area of ​​the engine outline, and allows for global stitching of the scanned engine outline data. This reduces the cumulative stitching errors caused by continuous stitching in traditional handheld scanners, improving inspection accuracy, shortening the inspection cycle, and increasing inspection efficiency.

[0004] The objective of this invention is achieved through the following technical solution.

[0005] The present invention discloses an automatic scanning and detection system for engine outline, comprising a multi-view vision measurement system, a line laser scanner with a spatial positioning device (hereinafter referred to as "line laser scanner"), a six-axis robotic arm, an engine support platform with multiple spatial positioning targets (hereinafter referred to as "engine support platform"), and control and data analysis software.

[0006] A line laser scanner acquires 3D topographic data of local areas of the engine's outline; a six-axis robotic arm enables large-scale automated scanning of the engine's outline; a high-precision lifting platform and a multi-view vision measurement system achieve global stitching of the topographic data acquired by the line laser scanner; the multi-view vision measurement system tracks and calculates the spatial pose of the engine support platform, and calculates the difference between the current pose of the engine under test and the pose of the planned robotic arm path in real time, achieving automatic compensation of the measurement path of the six-axis robotic arm, reducing the cumulative stitching error caused by continuous stitching during traditional handheld scanner scanning and measurement, and improving detection accuracy.

[0007] Preferably, the multi-view vision measurement system uses carbon fiber as the main structural material and incorporates a high-precision dual-axis tilt sensor to establish a horizontal reference. The image acquisition section consists of four sets of high-precision area array monochrome industrial cameras and industrial lenses, arranged in pairs to form two binocular vision measurement subsystems. Each industrial lens is equipped with a filter to remove ambient light interference from the target point being measured. The multi-view vision measurement system achieves real-time attitude measurement of the "line laser scanner" and the "engine support platform" through redundant measurement of the spatial positioning target on the spatial positioning device.

[0008] Preferably, the high-precision lifting platform uses carbon fiber as its main structural material and features a four-stage high-precision bolt lifting and self-locking mechanism to precisely adjust the positional relationship between the two binocular vision measurement subsystems in the multi-view vision measurement system. The high-precision lifting platform has three adjustable support bases to ensure long-term stability of the lifting platform and the multi-view vision measurement system on it. The high-precision lifting platform is used to adjust the field of view of the multi-view vision measurement system, enabling the measurement of the external contours of engines of different sizes.

[0009] Preferably, the "line laser scanner" has a spatial positioning device mounted on the outside of its main scanning structure. Each spatial positioning device has 16 spatial positioning targets. Each spatial positioning target uses carbon fiber as its main structural material and has six circular targets for observation by the multi-view vision system and one positioning hole for positioning the target ball of the laser tracker. By measuring the positioning hole using the laser tracker, the spatial coordinates of the six circular targets are assigned. This spatial positioning device can be recognized by the multi-view vision measurement system and its pose can be calculated. The relative relationship between the coordinate system of the spatial positioning device and the coordinate system of the scanning main structure is calibrated with high precision. The "line laser scanner" can scan point cloud data of a local area and convert the scanned point cloud data into the coordinate system of the multi-view vision measurement system through the positional relationship between the spatial positioning device and the scanning main structure.

[0010] Preferably, the end effector of the six-axis robotic arm has a flange with high rigidity and high load-bearing capacity. A line laser scanner with a spatial positioning device is fixed to the end effector of the six-axis robotic arm through the flange. The relative relationship between the base coordinate system of the six-axis robotic arm and the coordinate system of the multi-view vision measurement system is calculated by the multi-view vision measurement system. The relative relationship between the coordinate system of the end effector tool of the six-axis robotic arm and the coordinate system of the multi-view vision measurement system is calculated by the control and data analysis software.

[0011] Preferably, the "engine support platform" has 40 spatial positioning targets, and the spatial coordinates of the spatial positioning targets are calibrated using a laser tracker.

[0012] Preferably, the control and data analysis software is used to compensate for the movement trajectory of the robotic arm's end effector. When the relative positional relationship between the engine support platform and the six-axis robotic arm is inconsistent with the relative positional relationship during the path planning of the six-axis robotic arm, the movement trajectory of the robotic arm's end effector is compensated by calculating the deviation between the actual position of the "engine support platform" and the theoretical position during the planned path, thereby achieving flexible non-contact measurement of the engine's external contour.

[0013] This invention also discloses an automatic scanning and detection method for engine outline, implemented based on the aforementioned automatic scanning and detection system for engine outline, wherein the automatic scanning and detection method for engine outline is as follows:

[0014] Before the measurement process, the field of view of the multi-view vision measurement system is adjusted by adjusting the high-precision lifting platform according to the size of the engine being measured.

[0015] right cs-dual P cs-robot_base Perform calibration. cs-dual P cs-robot_base This represents the relative positional relationship between the coordinate system of the multi-view vision measurement system (cs-dual) and the base coordinate system of the six-axis robot (cs-robot_base).

[0016] right cs-set1 P cs-scan Perform calibration. cs-set1 P cs-scan This refers to the relative positional relationship between the main coordinate system (cs-scan) of the scanning structure of the "line laser scanner" and the coordinate system (cs-set1) of the spatial positioning device of the "line laser scanner".

[0017] During measurement, a line laser scanner obtains a series of point cloud coordinates. This represents the coordinates of the point cloud data in the main coordinate system (cs-scan) of the scanning structure of the "line laser scanner".

[0018] Then, the coordinates of these point clouds in the spatial positioning device coordinate system (cs-set1) of the "line laser scanner" are calculated. The calculation formula is as follows:

[0019]

[0020] Then, the relative position of the spatial positioning device coordinate system (cs-set1) of the "line laser scanner" with respect to the coordinate system (cs-dual) of the multi-view vision measurement system under the current posture of the robotic arm is calculated. cs-dual P cs-set1 The calculation formula is as follows:

[0021]

[0022] in This refers to the positioning point s on the spatial positioning device of the line laser scanner. i Coordinates in the coordinate system (cs-set1) of the spatial positioning device. This indicates its coordinates in the coordinate system of the multi-view vision measurement system (CS-Dual). Then, the point cloud data coordinates are changed from the coordinate system of the spatial positioning device of the line laser scanner (CS-Set1). Coordinates transformed to the coordinate system of a multi-view vision measurement system (CS-Dual). The calculation formula is as follows:

[0023]

[0024] Then, the relative positional relationship between the multi-view vision measurement system coordinate system (cs-dual) and the "engine support platform" coordinate system (cs-holder) under the current posture is calculated. cs-holder P cs-dual The calculation formula is as follows:

[0025]

[0026] in This indicates the positioning point g on the engine support platform. i Coordinates in the "engine support platform" coordinate system (cs-set1) This represents the coordinates of the point cloud within the multi-view vision measurement system. Then, the coordinates of these point clouds in the "engine support platform" coordinate system (cs-set1) are calculated. The calculation formula is as follows:

[0027]

[0028] The coordinate system transformation described above converts the point cloud data of the line laser scanner at each moment to the coordinates of the "engine support platform", thereby achieving global point cloud data stitching.

[0029] In actual measurement, the actual relative positional relationship between the "engine support platform" coordinate system (cs-holder) and the six-axis robotic arm base coordinate system (cs-robot_base) is as follows: cs-holder P cs-dual In path planning, the theoretical value of this relative positional relationship is... Therefore, the compensation path of the six-axis robotic arm in its current position on the "engine support platform" is calculated. The calculation formula is as follows:

[0030]

[0031] The compensation path is applied to each planned path of the six-axis robotic arm, thereby achieving collision-free movement and flexible, non-contact measurement of the engine's external contour.

[0032] Beneficial effects:

[0033] 1. The present invention discloses an automatic scanning and detection system and method for engine outline, which acquires three-dimensional topographic data of local areas of engine outline through a "line laser scanner". Compared with the traditional method of manually measuring key positions using steel tape measures and feeler gauges, it has the characteristics of high measurement accuracy and high efficiency.

[0034] 2. The present invention discloses an automatic scanning and detection system and method for engine outline, which uses a six-axis robotic arm equipped with a "line laser scanner" to measure the engine outline. It has the characteristics of wide single-station measurement range and high degree of standardization of measurement process. The measurement process designed for the same model of engine can be quickly applied to the measurement of multiple engines of the same model.

[0035] 3. The automatic scanning and detection system and method for engine outline disclosed in this invention, through a high-precision lifting platform and a multi-view vision measurement system, can flexibly adjust the space required for the measurement process, and can realize the measurement of the outline of engines of different sizes, thus improving the applicability of this system to different measured objects.

[0036] 4. This invention discloses an automatic scanning and detection system and method for engine outline. It uses a multi-view vision measurement system to track and calculate the spatial pose of an "engine support platform." Combined with pre-measurement calibration, it can calculate in real time the difference between the current pose of the engine under test and the pose of the planned robotic arm path, achieving automatic compensation for the measurement path of the six-axis robotic arm. This automatic compensation method avoids the limitation that the actual measurement equipment layout must maintain strict consistency with the simulation design, thus achieving flexible measurement.

[0037] 5. The automatic scanning and detection system and method for engine outline disclosed in this invention, based on achieving the above-mentioned beneficial effects 1, 2, 3, and 4, can meet the high-precision flexible measurement requirements of engine outline, and can realize the automated measurement of the outline of engines of various models and sizes. It has the advantages of standardized measurement process, high measurement efficiency, and less human intervention during the measurement process. Attached Figure Description

[0038] Figure 1 This is a structural composition diagram of an automatic scanning and detection system for engine outline disclosed in this invention;

[0039] Among them: 1- Multi-view vision measurement system, 2- High-precision lifting platform, 3- High-precision lifting platform support base, 4- Line laser scanner with spatial positioning device, 5- Six-axis robotic arm, 6- Engine support platform, 7- Spatial positioning target on engine support platform, 8- Object under test (air engine).

[0040] Figure 2 This invention discloses a line laser scanner with a spatial positioning device in an automatic scanning and detection system for engine outline.

[0041] Among them: 9-scanning main structure, 10-spatial positioning device of line laser scanner, 11-spatial positioning target on spatial positioning device, 12-end flange of six-axis robotic arm, 13-end of six-axis robotic arm.

[0042] Figure 3 This is a flowchart of the detection process of an automatic scanning and detection system for engine outline disclosed in this invention. Detailed Implementation

[0043] To better illustrate the purpose and advantages of the present invention, the invention will be further described below in conjunction with the accompanying drawings and examples.

[0044] Example 1:

[0045] like Figure 1As shown, this embodiment discloses an automatic scanning system for the outer contour of an engine, including a multi-view vision measurement system 1, a high-precision lifting platform 2, a line laser scanner 4 with a spatial positioning device (hereinafter referred to as "line laser scanner"), a six-axis robotic arm 5, an engine support platform 6 with multiple spatial positioning targets (hereinafter referred to as "engine support platform"), and control and data analysis software. The object under test 8 is an engine. The line laser scanner 4 acquires three-dimensional topographic data of a local area of ​​the engine's outer contour; the six-axis robotic arm 5 performs large-scale automated scanning of the outer contour of the object under test 8; the high-precision lifting platform 2 and the multi-view vision measurement system 1 achieve global stitching of the topographic data acquired by the line laser scanner 4; the multi-view vision measurement system 1 tracks and calculates the spatial pose of the engine support platform 6, and calculates the difference between the current pose of the engine under test 8 and the pose when the robotic arm is planned, thereby achieving automatic compensation of the measurement path of the six-axis robotic arm 5, reducing the cumulative stitching error caused by continuous stitching during traditional handheld scanner scanning and measurement, and improving detection accuracy.

[0046] The multi-view vision measurement system 1 can automatically detect and calculate spatial positioning targets in the field of view, including 16 spatial positioning targets 11 on the "line laser scanner" 4 and 40 spatial positioning targets 7 on the "engine support platform" 6.

[0047] like Figure 2 As shown, the "line laser scanner" 4 has a spatial positioning device 10 comprising 16 spatial positioning targets 11. Through a multi-view vision measurement system 1, these 16 spatial positioning targets 11 are measured in real time, enabling the conversion of scan data from the coordinate system of the scanning main structure to the coordinate system of the multi-view vision measurement system. This allows for real-time transmission of the scan data to control and data analysis software for preliminary stitching and display.

[0048] The "engine support platform" 6 includes 40 spatial positioning targets 7. The multi-view vision measurement system 1 measures these 40 spatial positioning targets 7 in real time and can convert the scanning data from the multi-view vision measurement system coordinate system to the "engine support platform" coordinate system.

[0049] like Figure 3 As shown in the figure, the detection method of the automatic scanning detection system for engine outline disclosed in this embodiment has the following specific implementation steps:

[0050] Step 1: Based on the dimensions of the engine being measured, adjust the high-precision lifting platform 2 to determine the field of view of the multi-view vision measurement system 1. Calibrate the relative positions of the cameras in the multi-view vision measurement system 1, and establish the multi-view vision measurement system coordinate system (CS-Dual) using the coordinate system of one of the cameras.

[0051] Step 2: Place the chessboard calibration plate at the end of the six-axis robotic arm 5 (13), and move the six-axis robotic arm 5 to multiple known spatial positions to achieve relative positional relationships. cs-dual P cs-robot_base The calibration. This relative positional relationship. cs- dual P cs-robot_base It refers to the relative positional relationship between the multi-view vision measurement system coordinate system (cs-dual) and the six-axis robot arm base coordinate system (cs-robot_base);

[0052] Step 3: Using a multi-view vision measurement system, determine the relative positions within the "line laser scanner" 4. cs- set1 P cs-scan Calibration is performed. The internal relative positional relationships are described. cs-set1 P cs-scan It refers to the relative positional relationship between the coordinate system of the scanning main structure (cs-scan) and the coordinate system of the spatial positioning device (cs-set1);

[0053] Step 4: Install the "line laser scanner" 4 at the end of the six-axis robotic arm;

[0054] Step 5: Use a laser tracker to measure the spatial coordinates of multiple spatial positioning targets 7 on the "engine support platform" 6, and establish the engine support platform coordinate system (cs-holder);

[0055] Step Six: The relative positional relationships obtained in Step Two cs-dual P cs-robot_base The digital models of the engine, the engine support platform, and the six-axis robotic arm equipped with the line laser scanner 4 are imported into the robotic arm path design software. The robotic arm path design software is used to design the running trajectory of the robotic arm end effector 13. During the design, it is ensured that the line laser scanner is kept at a certain distance from the engine surface. This distance is the depth of field distance of the line laser scanner 4. The running trajectory of the robotic arm end effector 13 is the measurement path of the six-axis robotic arm 5.

[0056] Step 7: Import the measurement path of the six-axis robotic arm 5 into the control and data analysis software, start the six-axis robotic arm 5, and begin scanning and measuring the engine's outer contour. During the measurement process, obtain the relative positional relationship between the multi-view vision measurement system coordinate system (CS-Dual) and the engine support platform coordinate system (CS-Holder) at each moment. cs-holder P cs-dual ,use cs-holder P cs-dualCalculate the relative positional relationship between the "engine support platform" coordinate system (cs-holder) and the six-axis robot arm base coordinate system (cs-robot_base). cs-robot_base P cs-holder ;

[0057] Step 8: The multi-view vision measurement system 1 uses the spatial positioning device 10 on the line laser scanner 4 to align the point cloud data obtained by the line laser scanner 4 to the coordinate system of the engine support platform.

[0058] Step 8.1: Obtain the main structure of the scan and get a series of point cloud coordinates. This represents the coordinates of the point cloud data in the coordinate system of the main structure (cs-scan) during online scanning, and calculates the coordinates of these point clouds in the spatial positioning device coordinate system (cs-set1) of the "line laser scanner".

[0059] Step 8.2: Calculate the relative position of the spatial positioning device coordinate system (cs-set1) of the "line laser scanner" 4 with respect to the coordinate system (cs-dual) of the multi-view vision measurement system. cs-dual P cs-set1 ;

[0060] Step 8.3: Calculate the relative position of the multi-view vision measurement system coordinate system (cs-dual) with respect to the engine support platform coordinate system (cs-holder) in the current attitude. cs-holder P cs-dual ;

[0061] Step 8.4: Calculate the coordinates of these point clouds in the engine support platform coordinate system (cs-set1).

[0062] Step 9: Calculate the compensation path for the end effector 13 of the six-axis robotic arm to move to the next position;

[0063] Calculate the compensation path of the six-axis robotic arm 5 The calculation formula is as follows:

[0064]

[0065] in cs-holder P cs-dual This represents the actual relative position of the multi-view vision measurement system coordinate system (cs-dual) with respect to the engine support platform coordinate system (cs-holder). This represents the theoretical relative positional relationship between the engine support platform coordinate system (cs-holder) and the six-axis robot arm base coordinate system (cs-robot_base);

[0066] Step 10: Repeat steps 7 to 9 until the entire planned path of the six-axis robotic arm 5 is completed and all key parts of the engine's outline are scanned. During this process, the engine can be moved to different positions via the engine support platform 6 according to the planned process to measure the outline of the key parts of the engine's main body.

[0067] Step 11: After completing the scanning and measurement of all key parts of the engine body, the six-axis robotic arm 5, equipped with a "line laser scanner" 4, scans the positioning target 7 on the engine support platform 6;

[0068] Step 12: Using the scanning data of the positioning target 7, perform coordinate least squares fitting to achieve the fitting of engine measurement data with mathematical model;

[0069] Step 13: Using the fitted engine measurement data and mathematical model, calculate the deviation between the actual engine profile measurement data and the engine digital model. During the calculation, each measurement data point is vertically projected onto the theoretical digital model to obtain its projection point on the engine digital model. The distance between this projection point and the measurement data point is the deviation value.

[0070] The above detailed description further illustrates the purpose, technical solution, and beneficial effects of the invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for automatic scanning and detecting engine profile, characterized in that: The system for realizing an engine contour automatic scanning detection method comprises a multi-view vision measurement system, a line laser scanner with a spatial positioning device, a six-axis mechanical arm, an engine support platform with multiple spatial positioning targets, control and data analysis software; The three-dimensional topographic data of the local area of the engine contour is acquired by the line laser scanner; the six-axis mechanical arm realizes large-scale automatic scanning of the engine contour; the high-precision lifting platform and the multi-view vision measurement system realize global splicing of the topographic data collected by the line laser scanner; the multi-view vision measurement system tracks and solves the spatial pose of the engine support platform, real-time solves the pose difference between the current pose of the measured engine and the pose when the mechanical arm path is planned, realizes automatic compensation of the measurement path of the six-axis mechanical arm, reduces the cumulative splicing error caused by continuous splicing when the traditional handheld scanner is scanned and measured, and improves the detection accuracy; The method comprises the following steps, Step one: according to the size of the measured engine, adjust the high-precision lifting platform to determine the field of view range of the multi-view vision measurement system; calibrate the relative position relationship between the cameras of the multi-view vision measurement system, and establish the multi-view vision measurement system coordinate system cs-dual in the coordinate system of one of the cameras; Step two: Place the chessboard calibration plate at the end of the six-axis robot, move multiple known spatial positions through the robot, and achieve the relative position relationship cs-dual P cs-robot_base Calibration The relative position relationship cs-dual P cs-robot_base is the relative position relationship between the coordinate system cs-dual of the multi-view vision measurement system and the base coordinate system cs-robot_base of the six-axis robot arm; Step three: using a multi-view vision measurement system to measure the relative position relationship inside the line laser scanner cs-set1 P cs-scan Calibration is performed; the relative position relationship inside cs-set1 P cs-scan is the relative position relationship between the scanning body structure coordinate system cs-scan and the spatial positioning device coordinate system cs-set1; Step four: install the line laser scanner at the end of the six-axis mechanical arm; Step five: use the laser tracker to measure the spatial coordinates of the multiple spatial positioning targets on the engine support platform, and establish the engine support platform coordinate system cs-holder; Step six: the relative position relationship obtained in step two is used to determine the position of the laser line scanner on the six-axis robot cs-dual P cs-robot_base , the engine digital model, the engine support platform digital model, and the six-axis robot digital model carrying the laser line scanner are imported into the robot path design software. Through the mechanical arm path design software, the running track of the mechanical arm end is designed, and when designing, the line laser scanner is kept at a certain distance from the engine surface, which is the depth of field distance of the line laser scanner; the running track of the mechanical arm end is the measurement path of the six-axis mechanical arm; Step seven: the measurement path of the six-axis robot arm is introduced into the control and data analysis software, the six-axis robot arm is started, and the scanning measurement of the engine contour is started; during the measurement process, the relative position relationship of the multi-view vision measurement system coordinate system cs-dual relative to the engine support platform coordinate system cs-holder at each moment is obtained cs-holder P cs-dual , the relative position relationship of the engine support platform coordinate system cs-holder and the six-axis robot arm base coordinate system cs-robot_base is calculated cs- holader P cs-dual , the relative position relationship of the engine support platform coordinate system cs-holder and the six-axis robot arm base coordinate system cs-robot_base is calculated cs-robot_base P cs-holder ; Step eight: the multi-view vision measurement system aligns the point cloud data obtained by the line laser scanner to the engine support platform coordinate system through the spatial positioning device on the line laser scanner; Step 8.1 : Obtaining a series of point cloud coordinates by scanning the subject structure representing the coordinates of the point cloud data in the coordinate system cs-scan of the online scanning of the subject structure, the coordinates of these point clouds are calculated in the coordinate system cs-setl of the spatial positioning device of the online laser scanner Step 8.2: Calculate the relative position relationship of the spatial positioning device coordinate system cs-set1 of the line laser scanner relative to the dual-camera vision measurement system coordinate system cs-dual cs-dual P cs-set1 ; Step 8.3: Calculate the relative position relationship of the multi-view vision measurement system coordinate system cs-dual relative to the engine support platform coordinate system cs-holder under the current attitude cs-holder P cs-dual ; Step 8.4: Compute the coordinates of these point clouds in the engine support platform coordinate system cs-holder Step nine: calculate the compensation path of the six-axis mechanical arm end moving to the next position; Computing a compensated path for a six-axis robot The formula is as follows: wherein cs-holder P cs-dual is the actual relative position relationship of the multi-view vision measurement system coordinate system (cs-dual) relative to the engine support platform coordinate system cs-holder, is the theoretical relative position relationship of the engine support platform coordinate system cs-holder and the six-axis robot base coordinate system cs-robot_base, the control and data analysis software transmits the calculated compensated path to the six-axis robot, and controls the movement of the robot end along the compensated path. Step ten: repeat steps seven to nine until the entire planned path of the six-axis mechanical arm is completed, the entire key part scanning of the engine contour is completed, and during the process, the engine can be moved to different positions by the engine support platform according to the planned process to realize the measurement of the entire main key part of the engine; Step eleven: after completing the entire scanning and measurement of the main key part of the engine, the six-axis mechanical arm carries the line laser scanner to scan the positioning targets on the engine support platform; Step twelve: use the scanning data of the positioning targets to perform coordinate least squares fitting to realize the fitting of the engine measurement data and the mathematical model; Step three: using the fitted engine measurement data and mathematical model, calculate the engine actual shape contour measurement data and engine digital model deviation; when calculating, the vertical projection of each measurement data point to the theoretical digital model is obtained, the projection point of the measurement data point on the engine digital model, the distance between the projection point and the measurement data point is the deviation value of the measurement position, the deviation value is automatically calculated by the control software, which can avoid the cumulative error caused by continuous splicing when using traditional handheld scanner for scanning measurement, and improve the detection accuracy and efficiency.

2. The method of claim 1, wherein: The multi-view vision measurement system adopts carbon fiber material as the structural main body, and is internally provided with a high-precision dual-axis inclination sensor for establishing a horizontal reference; the image acquisition part is four sets of high-precision area array black and white industrial cameras and industrial lenses, two by two, forming two binocular vision measurement subsystems, the industrial lenses are provided with optical filters in front, which are used to filter out environmental light interference other than the measured target points; the multi-view vision measurement system realizes real-time attitude measurement of the line laser scanner and the engine support platform through redundant measurement of the space positioning targets on the space positioning device.

3. The method of claim 1, wherein: the engine profile is automatically scanned and detected by: determining a first engine profile; determining a second engine profile; and determining a difference between the first engine profile and the second engine profile. The high-precision lifting platform adopts carbon fiber material as the structural main body, and has four-stage high-precision bolt lifting and self-locking mechanisms for realizing accurate adjustment of the positional relationship between the two binocular vision measurement subsystems in the multi-view vision measurement system; the high-precision lifting platform has three adjustable support bases to ensure the long-term stability of the multi-view vision measurement system on the lifting platform; the high-precision lifting platform is used to adjust the field of view of the multi-view vision measurement system to realize the shape contour measurement of engines of different sizes.

4. The automatic scanning and detection method for engine outline as described in claim 1, characterized in that: The line laser scanner scanning main structure is provided with a space positioning device on the outside, and each space positioning device has 16 space positioning targets; each space positioning target adopts carbon fiber material as the structural main body, and is provided with six circular targets for observation by the multi-view vision measurement system and a positioning hole for positioning a target ball of a laser tracker; the space coordinates of the six circular targets are determined by measuring the positioning hole with the laser tracker; the space positioning device can be recognized by the multi-view vision measurement system and pose calculation is performed, the relative relationship between the space positioning device coordinate system and the scanning main structure coordinate system is calibrated with high precision; the line laser scanner can realize scanning of point cloud data in a local area, and convert the scanned point cloud data to the multi-view vision measurement system coordinate system through the positional relationship between the space positioning device and the scanning main structure.

5. The automatic scanning and detection method for engine outline as described in claim 1, characterized in that: The six-axis mechanical arm has a flange with high rigidity and high bearing capacity, the line laser scanner with the space positioning device is fixed on the end of the six-axis mechanical arm through the flange, the relative relationship between the six-axis mechanical arm base coordinate system and the multi-view vision measurement system coordinate system is calculated by the multi-view vision measurement system, and the relative relationship between the six-axis mechanical arm end tool coordinate system and the multi-view vision measurement system coordinate system is calculated by the control and data analysis software.

6. A method for automatic detection of engine profile scanning as recited in claim 1, wherein: The engine support platform has 40 space positioning targets, and the space coordinates of the space positioning targets are calibrated by a laser tracker.

7. The automatic scanning and detection method for engine outline as described in claim 1, characterized in that: The control and data analysis software is used for compensating the moving track of the end of the mechanical arm; when the relative position relationship between the engine support platform and the six-axis mechanical arm is inconsistent with the relative position relationship during the path planning of the six-axis mechanical arm, the moving track of the end of the mechanical arm is compensated by calculating the deviation between the actual position of the engine support platform and the theoretical position during the planned path, so as to realize the flexible non-contact measurement of the engine contour.

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