Method for determining phase connection of measuring shafting based on visual guidance

Abstract

The invention relates to the technical field of visual assembly of speed reducers, and discloses a method for measuring shafting and determining phase connection based on visual guidance. T-shaped marks are respectively etched on an input end measuring coupling shaft and an output end measuring coupling shaft of the speed reducer, the transverse edge length, the vertical edge length and the width of the T-shaped marks, the outer diameter of a spline and the tooth pitch of the spline meet the required relation, the accuracy of camera image recognition is improved, and therefore the assembling accuracy of the speed reducer is improved; in addition, the rotation angle of the high-speed end measurement shaft system is determined through the phase of the high-speed end measurement shaft system under the standard state condition and the actual state condition and the included angle between the transverse edge of the T-shaped identifier of the coupling shaft and the positive direction of the X axis under a camera coordinate system measured by the input end of the speed reducer, and accurate phase connection of the high-speed end measurement coupling shaft and the input end of the speed reducer is achieved; similarly, accurate phase connection of the low-speed end and the speed reducer output end measurement connecting shaft is realized. Therefore, precise and automatic assembling of the speed reducer is achieved.

Description

Technical Field

[0001] The present application relates to the technical field of visual assembly of reducers, and in particular to a method for measuring a shaft system and determining phase connection based on visual guidance. Background Art

[0002] Reducers are key parts in the manufacturing industry, and accurate detection of their performance requires the use of high-precision detectors. Although manual assembly of reducers can adapt to some complex situations, due to the large number of reducers, manual operation is prone to fatigue, resulting in greatly reduced efficiency and accuracy, making it difficult to meet the needs of large-scale detection in industrial production. The use of an automatic assembly system can avoid the inefficiency of instrument use caused by manual assembly. At the same time, it can improve the safety of the handling process and effectively avoid the possibility of worker safety accidents during the assembly process.

[0003] In order to realize the automatic assembly of the reducer, splines are used as the connection mode between the input and output ends of the transmission chain of the reducer under test and the high and low speed measuring shaft systems, so as to realize the quick-change connection of the high-speed and low-speed shaft systems.

[0004] However, how to make the reducer accurately phase-connected with the high-speed end and the low-speed end respectively when using spline connection has become an urgent problem to be solved. Summary of the invention

[0005] In order to solve the above technical problems, the present application provides a method for measuring an axis system and determining a phase connection based on visual guidance, comprising the following steps: S1: Measure the coupling shaft at the input end and the output end of the reducer, and etch a T-shaped mark on each of them; the size of the T-shaped mark satisfies the following relationship: L h = k1×D; L v = k2×D, and L v / L h = m; W = k3×(D / P) n ×D; |L v -L h |≤ΔL; Among them, L h Indicates the horizontal length of the T-shaped logo, L v represents the length of the vertical side of the T-shaped mark, D represents the outer diameter of the spline, P represents the pitch of the spline, k1, k2, k3 are proportional coefficients, m is the proportional constant, n is the exponential factor, W represents the width of the horizontal side of the T-shaped mark, and ΔL represents the preset length difference threshold; S2: Obtaining the standard connection phase state, the high-speed end measures the shaft phase φ1, the horizontal side of the T-shaped mark at the reducer input end forms an angle α1 with the positive direction of the X-axis in the camera coordinate system, the low-speed end measures the shaft phase φ2, and the horizontal side of the T-shaped mark at the reducer output end forms an angle α2 with the positive direction of the X-axis in the camera coordinate system; the standard connection phase state is the state in which the high-speed end is connected to the reducer input end, and the low-speed end is connected to the reducer output end when in the test station; S3: Move the high-speed end to the preparation station, obtain the phase γ1 of the high-speed end measurement axis system in the camera coordinate system and the angle β1 between the horizontal side of the T-shaped mark at the reducer input end and the positive direction of the X axis in the camera coordinate system; S4: Calculate the rotation angle Δ1 of the measuring shaft system at the high-speed end according to γ1, β1, φ1 and α1; S5: Rotate the high-speed end measuring shaft system by Δ1, connect it to the reducer input end, and then move it to the test station; S6: Obtain the phase γ2 of the measuring axis system at the low speed end in the camera coordinate system, and the angle β2 between the horizontal side of the T-shaped mark at the output end of the reducer and the positive direction of the X axis in the camera coordinate system; S7: Calculate the rotation angle Δ2 of the measured shaft system at the low speed end according to γ2, β2, φ2 and α2; S8: Rotate the low-speed end measuring shaft system by Δ2 and connect it to the output end of the reducer to complete the phase connection.

[0006] Furthermore, the calculation formula for measuring the shaft rotation angle Δ1 at the high-speed end is: Δ1= ( γ 1-φ1) - ( β 1- α 1); If Δ1 is a negative value, it means that the high-speed end measuring shaft system rotates counterclockwise by an angle of |Δ1|; If Δ1 is a non-negative value, it means that the high-speed end measuring shaft system rotates clockwise by an angle |Δ1|.

[0007] Furthermore, the calculation formula for measuring the shaft rotation angle Δ2 at the low speed end is: Δ2= ( γ 2-φ2) - ( β 2- α 2).

[0008] If Δ2 is a negative value, it means that the high-speed end measuring shaft system rotates counterclockwise by an angle of |Δ2|; If Δ2 is a non-negative value, it means that the high-speed end measuring shaft system rotates clockwise by an angle |Δ2|.

[0009] Furthermore, in the standard connection phase state, the method for obtaining the angle α1 between the horizontal side of the T-shaped mark at the reducer input end and the positive direction of the X-axis in the camera coordinate system is: The T-shaped mark at the input end of the reducer is photographed by a camera vision measurement system to obtain a first image; Identify the edge of the T-shaped mark in the first image, perform binarization processing, obtain the edges of the horizontal and vertical sides of the T-shaped mark, and fit the straight line equations of the two sides in the camera coordinate system; Select two points A and B on the same side of the vertical edge of the T-shaped mark, and calculate the difference δ between the two points in the Y direction; According to the slope k and δ of the straight line equation of the vertical side of the T-shaped mark and the acute angle θ between the horizontal side of the T-shaped mark and the positive direction of the X-axis (zero phase) in the camera coordinate system, determine the angle α1 between the horizontal side of the T-shaped mark at the input end of the reducer and the positive direction of the X-axis in the camera coordinate system.

[0010] Furthermore, according to the slope k and δ of the straight line equation of the vertical side of the T-shaped mark and the acute angle θ between the horizontal side of the T-shaped mark and the positive direction of the X-axis (zero phase) in the camera coordinate system, the angle α1 between the horizontal side of the T-shaped mark at the input end of the reducer and the positive direction of the X-axis in the camera coordinate system is determined as follows: If the slope k of the equation of the vertical side of the T-shaped marker is less than 0 and δ>0, then α1=θ; If the slope k of the equation of the vertical side of the T-shaped marker is less than 0 and δ<0, then α1=180º+θ; If the slope k of the equation of the vertical side of the T-shaped marker is greater than 0 and δ>0, then α1=360º-θ; If the slope k of the equation of the vertical side of the T-shaped marker is greater than 0 and δ<0, then α1=180º-θ.

[0011] Furthermore, the angle β1 between the horizontal side of the T-shaped mark at the input end of the reducer and the positive direction of the X-axis in the camera coordinate system is obtained, which includes: The T-shaped mark at the input end of the reducer is photographed by a camera vision measurement system to obtain a second image; Identify the edge of the T-shaped mark in the second image, perform binarization processing, obtain the edges of the horizontal and vertical sides of the T-shaped mark, and fit the straight line equations of the two sides in the camera coordinate system; Select two points A` and B` on the same side of the vertical edge of the T-shaped mark, and calculate the difference δ` between the two points in the Y direction; According to the slope k`, δ` of the straight line equation of the vertical side of the T-shaped mark and the acute angle θ` between the horizontal side of the T-shaped mark and the positive direction of the X-axis (zero phase) in the camera coordinate system, determine the angle β1 between the horizontal side of the T-shaped mark at the input end of the reducer and the positive direction of the X-axis in the camera coordinate system.

[0012] Furthermore, according to the slope k', δ' of the straight line equation of the vertical side of the T-shaped mark and the acute angle θ' between the horizontal side of the T-shaped mark and the positive direction of the X-axis (zero phase) in the camera coordinate system, the angle β1 between the horizontal side of the T-shaped mark at the input end of the reducer and the positive direction of the X-axis in the camera coordinate system is determined as: If the slope k` of the equation of the vertical side of the T-shaped marker is less than 0 and δ`>0, then β1=θ`; If the slope k` of the equation of the vertical side of the T-shaped marker is less than 0 and δ`<0, then β1=180º+θ`; If the slope k` of the equation of the vertical side of the T-shaped marker is greater than 0 and δ`>0, then β1=360º-θ`; If the slope k` of the equation of the vertical side of the T-shaped marker is greater than 0 and δ`<0, then β1=180º-θ`.

[0013] Further, the slots at the high-speed end, the spline teeth at the input end of the reducer, the slots at the low-speed end, and the spline teeth at the output end of the reducer are numbered respectively; When the high-speed end is phase-connected with the reducer input end, the slot number of the high-speed end is consistent with the number of the spline teeth of the reducer input end; When the low-speed end is phase-connected with the output end of the reducer, the slot number of the low-speed end is consistent with the number of the spline teeth of the output end of the reducer.

[0014] Furthermore, the horizontal width W of the T-shaped mark is not less than a preset width threshold W min .

[0015] The embodiments of the present application have the following technical effects: 1. The method for determining phase connection by measuring shaft system based on vision guidance provided in the present application is to etch T-shaped marks at the input and output ends of the reducer respectively, and the horizontal length, vertical length and width of the T-shaped marks meet the required relationship with the outer diameter of the spline and the tooth pitch of the spline, thereby improving the accuracy of camera image recognition and thus improving the assembly accuracy of the reducer; 2. Measure the shaft phase at the high-speed end under standard conditions and actual conditions 、 The angle between the horizontal side of the T-shaped mark on the reducer input end and the positive direction of the X-axis in the camera coordinate system determines the rotation angle of the high-speed end measurement axis system, and realizes the precise phase connection between the high-speed end and the reducer input end; similarly, the precise phase connection between the low-speed end and the reducer output end is realized. In this way, the precise automatic assembly of the reducer is realized. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0017] Figure 1 It is a flow chart of a method for determining phase connection of a shaft system based on visual guidance provided in an embodiment of the present application; Figure 2 It is a schematic diagram of the angle between the high-speed end measurement shaft phase and the horizontal side of the T-shaped mark at the reducer input end and the positive direction of the X-axis in the camera coordinate system in the standard connection phase state provided in an embodiment of the present application; Figure 3 It is a schematic diagram of the angle between the horizontal side of the T-shaped mark at the input end of the reducer and the positive direction of the X-axis in the camera coordinate system in the actual assembly state provided by the embodiment of the present application; Figure 4 It is a schematic diagram of the internal structure of the system provided in the embodiment of the present application and the position of the first camera vision measurement system at the high-speed end; Figure 5 It is a schematic diagram of the external structure of the detector system provided in the embodiment of the present application (excluding the camera visual measurement system); Figure 6 is a schematic diagram of the positions of a second camera vision measurement system and a workbench provided in an embodiment of the present application; Figure 7 It is a schematic diagram of the structure of a first camera vision measurement system connected to a high-speed end provided in an embodiment of the present application; Figure 8 It is a schematic diagram of the structure of a second camera vision measurement system installed on a workbench provided in an embodiment of the present application.

[0018] 1. T-shaped mark; 2. Horizontal side of T-shaped mark; 3. Vertical side of T-shaped mark; 4. External spline end face; 5. High-speed end motor; 6. High-speed end barrel-shaped stand; 7. High-speed end measuring shaft system; 8. Transported object (measured reducer and adapter); 9. Low-speed end barrel-shaped stand; 10. Low-speed end measuring shaft system; 11. Low-speed end motor; 12. First set of camera vision measurement system; 13. Workbench body; 14. Preparation station; 15. Guide rail system; 16. Test station; 17. Second set of camera vision measurement system; 18. Extension plate; 19. Camera mounting bracket I; 20. Camera system I; 21. Camera system II; 22. Camera mounting bracket II. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solution and advantages of the present application clearer, the technical solution of the present application will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work belong to the scope of protection of the present application.

[0020] As attached Figures 4 to 8 As shown, a method for determining phase connection of a measuring shaft system based on vision guidance is provided, wherein the detector involved is a prior art, including a workbench 13, a guide rail system 15, a high-speed end, a low-speed end, and a transported object (a reducer and adapter to be measured) 8. The high-speed end includes a high-speed end motor 5, a high-speed end barrel-shaped stand 6, a high-speed end measuring shaft system 7 (including a high-speed end torque sensor and a high-speed end circular grating angle sensor), etc. The low-speed end includes a low-speed end barrel-shaped stand 9, a low-speed end measuring shaft system 10 (including a low-speed end torque sensor and a low-speed end circular grating angle sensor), a low-speed end motor 11, etc. The guide rail system 15 includes a two-dimensional motion guide rail system and can move within its plane.

[0021] The system required for a method for determining phase connection of a measuring axis system based on visual guidance includes a first camera vision measurement system 12 and a second camera vision measurement system 17. The first camera vision measurement system 12 includes an extension plate 18, a camera mounting frame I19 and a camera system I20; the camera system I20 is fixed on the camera mounting frame I19, and needs to have its own light source or an external light source to ensure the shooting quality of the T-shaped mark under the field of view environment; the camera mounting frame I19 is fixed on the extension plate 18; the extension plate 18 is fixed on the outside of the high-speed end barrel 6. The second camera vision measurement system 17 includes a camera mounting frame II22 and a camera system II21; the camera mounting frame II22 is fixed on the workbench, and is structured accordingly according to the structural characteristics of the workbench and the test station; the camera system II21 is fixed on the camera mounting frame II22, and the shooting field of view is directly opposite to the center of the preparation station 14.

[0022] The application provides a method for determining phase connection of a measuring shaft system based on visual guidance, such as Figure 1 As shown, the following steps are included: S1: Etch a T-shaped mark 1 at the input and output ends of the reducer; T-shaped marks are etched on the external spline end faces 4 at both the input and output ends of the reducer. The T-shaped marks have clear horizontal and vertical edge structures, which are more visually prominent and easy for the camera vision measurement system to capture and identify. In contrast, although the I-shaped mark also has vertical and horizontal structures, its vertical part is divided into two sections, which may increase the complexity and uncertainty during identification. The edges of the T-shaped mark are clearer, especially when performing binarization and edge extraction, the position information of the horizontal and vertical edges can be obtained more accurately. The edges of the I-shaped mark may become more complex due to segmentation, increasing the difficulty of identification.

[0023] Moreover, the angle calculation of the T-shaped mark is relatively simple. The angle with the positive direction of the X-axis (zero phase) in the camera coordinate system can be quickly determined by the linear equation of the horizontal side 2 and the vertical side 3 of the T-shaped mark, which can reduce the error in calculating the angle. However, due to its complex structure, the I-shaped mark may require more calculation steps and more complex algorithms to determine its angle, which may introduce more uncertainty and errors in angle calculation.

[0024] Therefore, the present application etches T-shaped marks on the input and output ends of the reducer, respectively, which helps to improve the accuracy and stability of phase identification.

[0025] However, the dimensions of the T-shaped logo satisfy the following relationship: L h = k1×D; L v = k2×D, and L v / L h = m; the shape proportion of the T-shaped logo is controlled by the proportional constant m, the clarity of the logo is maintained, and the camera recognition accuracy is improved.

[0026] W = k3×(D / P) n ×D; The effect of the tooth pitch on the width is taken into consideration, so that when the tooth pitch is larger, the horizontal width of the T-shaped logo can be appropriately increased to maintain the clarity of the logo.

[0027] |L v -L h |≤ΔL; the length difference threshold ΔL is used to control the shape of the T-shaped logo so as not to be too narrow or flat.

[0028] Among them, L h Indicates the horizontal length of the T-shaped logo, L v represents the length of the vertical side of the T-shaped mark, D represents the outer diameter of the spline, P represents the pitch of the spline, k1, k2, k3 are proportional coefficients, m is the proportional constant, n is the exponential factor, W represents the width of the horizontal side of the T-shaped mark, and ΔL represents the preset length difference threshold; Furthermore, the horizontal width W of the T-shaped mark is not less than a preset width threshold W min . Width threshold W min It is the minimum width threshold, which is used to ensure the clarity of the logo in image recognition.

[0029] In practical applications, it is necessary to determine these proportional coefficients k1, k2, k3, proportional constant (m), exponential factor (n), minimum width threshold W through experiments and debugging according to the specific reducer model, measurement system accuracy and image recognition algorithm requirements. min The specific values ​​of the length difference threshold ΔL should be determined to ensure that the T-shaped mark has sufficient clarity and stability in image recognition and meets the accuracy requirements of the measurement system.

[0030] The present application provides a method for measuring the shaft system and determining the phase connection based on visual guidance. T-shaped marks are respectively etched at the input and output ends of the reducer. The horizontal length, vertical length, and width of the T-shaped mark meet the required relationship with the outer diameter of the spline and the tooth pitch of the spline, thereby improving the accuracy of camera image recognition and thus improving the assembly accuracy of the reducer.

[0031] S2: Obtain the standard connection phase state, the high-speed end measures the shaft phase φ1, the horizontal side of the T-shaped mark at the reducer input end forms an angle α1 with the positive direction of the X-axis in the camera coordinate system, the low-speed end measures the shaft phase φ2, and the horizontal side of the T-shaped mark at the reducer output end forms an angle α2 with the positive direction of the X-axis in the camera coordinate system; the standard connection phase state is the state in which the high-speed end is connected to the reducer input end, and the low-speed end is connected to the reducer output end at the test station; this application first obtains the above angles under the standard connection phase state. These angles are the angles when the high-speed end measures the shaft system, the reducer, and the low-speed end are placed in the test station and can be assembled.

[0032] It should be noted that the angles obtained in step S2 only need to be calibrated and measured once. When multiple reducers are subsequently assembled, although the phase of each reducer placed on the preparation station is random, only steps S3-S8 need to be repeated. The rotation angles of the shaft systems measured at the high and low speed ends during each assembly are calculated based on the angles under the same standard connection phase state.

[0033] Place the reducer under test at the test station, without changing the phase state of the high- and low-speed end measuring shaft systems and the reducer under test, move the reducer under test and the adapter to a suitable camera shooting position for shooting.

[0034] Furthermore, in the standard connection phase state, the method for obtaining the angle α1 between the horizontal side of the T-shaped mark at the reducer input end and the positive direction of the X-axis in the camera coordinate system is: The T-shaped mark at the input end of the reducer is photographed by a camera vision measurement system to obtain a first image; Identify the edge of the T-shaped mark in the first image, perform binarization processing, obtain the edges of the horizontal and vertical sides of the T-shaped mark, and fit the straight line equations of the two sides in the camera coordinate system; Select two points A and B on the same side of the vertical edge of the T-shaped mark, and calculate the difference δ between the two points in the Y direction. δ = Y A -Y B ; The positions of points A and B are shown schematically Figure 3 .

[0035] According to the slope k and δ of the straight line equation of the vertical side of the T-shaped mark and the acute angle θ between the horizontal side of the T-shaped mark and the positive direction of the X-axis (zero phase) in the camera coordinate system, determine the angle α1 between the horizontal side of the T-shaped mark at the input end of the reducer and the positive direction of the X-axis in the camera coordinate system.

[0036] Furthermore, according to the slope k and δ of the straight line equation of the vertical side of the T-shaped mark and the acute angle θ between the horizontal side of the T-shaped mark and the positive direction of the X-axis (zero phase) in the camera coordinate system, the angle α1 between the horizontal side of the T-shaped mark at the input end of the reducer and the positive direction of the X-axis in the camera coordinate system is determined as follows: If the slope k of the equation of the vertical side of the T-shaped marker is less than 0 and δ>0, then α1=θ; If the slope k of the equation of the vertical side of the T-shaped marker is less than 0 and δ<0, then α1=180º+θ; If the slope k of the equation of the vertical side of the T-shaped marker is greater than 0 and δ>0, then α1=360º-θ; If the slope k of the equation of the vertical side of the T-shaped marker is greater than 0 and δ<0, then α1=180º-θ.

[0037] Similarly, in the standard connection phase state, the method for obtaining the angle α2 between the horizontal side of the T-shaped mark at the output end of the reducer and the positive direction of the X-axis in the camera coordinate system is the same as α1, which will not be repeated here.

[0038] For example, at the test station 16, the measured reducer and adapter are positioned and assembled with the high-speed and low-speed end measurement systems by manual debugging, and the measured shaft connection state is used as the standard connection phase state, such as Figure 2 The circular grating angle measurement system in the high-speed and low-speed end measurement systems records the phase φ1 of the high-speed end measurement axis system and the phase φ2 of the low-speed end measurement axis system at this time, and obtains the angle α1 between the horizontal side of the T-shaped mark at the input end of the reducer and the positive direction of the X-axis in the camera coordinate system and the angle α between the horizontal side of the T-shaped mark at the output end of the reducer and the positive direction of the X-axis in the camera coordinate system through the first camera vision measurement system 12 and the second camera vision measurement system 17.2。

[0039] S3: Move the high-speed end to the preparation station, obtain the phase γ1 of the high-speed end measurement axis system and the angle β between the horizontal side of the T-shaped mark at the reducer input end and the positive direction of the X-axis in the camera coordinate system. 1。

[0040] In order to achieve the rapid replacement of the reducer under test, the shaft system is connected with an involute spline, including the high-speed measuring shaft system and the input end of the reducer under test, and the low-speed measuring shaft system and the output end of the reducer under test. When the reducer is actually assembled, the reducer is placed in the preparation station. The state of the input and output ends is random when not assembled and connected, so the phase of the external spline connected to the measuring shaft system is random.

[0041] like Figure 3 As shown, the transported object (the reducer and adapter to be tested) 8 is placed on the preparation station 14 of the detector to form a component to be tested. The high-speed end carries the first camera measurement system 12 under the movement of the detector rail system to the top of the reducer input shaft (top of the preparation station 14), photographs the T-shaped mark on the end face of the spline shaft at the input end of the reducer, and obtains the angle β1 between the input end spline T-shaped mark and the zero phase in the camera coordinate system.

[0042] The calculation method of β1 specifically includes: The T-shaped mark at the input end of the reducer is photographed by a camera vision measurement system to obtain a second image; Identify the edge of the T-shaped mark in the second image, perform binarization processing, obtain the edges of the horizontal and vertical sides of the T-shaped mark, and fit the straight line equations of the two sides in the camera coordinate system; Select two points A` and B` on the same side of the vertical edge of the T-shaped mark, and calculate the difference δ` between the two points in the Y direction. δ` = Y A `-Y B ` ; According to the slope k`, δ` of the straight line equation of the vertical side of the T-shaped mark and the acute angle θ` between the horizontal side of the T-shaped mark and the positive direction of the X-axis (zero phase) in the camera coordinate system, determine the angle β1 between the horizontal side of the T-shaped mark at the input end of the reducer and the positive direction of the X-axis in the camera coordinate system.

[0043] Furthermore, according to the slope k', δ' of the straight line equation of the vertical side of the T-shaped mark and the acute angle θ' between the horizontal side of the T-shaped mark and the positive direction of the X-axis (zero phase) in the camera coordinate system, the angle β1 between the horizontal side of the T-shaped mark at the input end of the reducer and the positive direction of the X-axis in the camera coordinate system is determined as: If the slope k` of the equation of the vertical side of the T-shaped marker is less than 0 and δ`>0, then β1=θ`; If the slope k` of the equation of the vertical side of the T-shaped marker is less than 0 and δ`<0, then β1=180º+θ`; If the slope k` of the equation of the vertical side of the T-shaped marker is greater than 0 and δ`>0, then β1=360º-θ`; If the slope k` of the equation of the vertical side of the T-shaped marker is greater than 0 and δ`<0, then β1=180º-θ`.

[0044] S4: Calculate the rotation angle Δ1 of the measuring shaft system at the high-speed end according to γ1, β1, φ1 and α1; Furthermore, the calculation formula for measuring the shaft rotation angle Δ1 at the high-speed end is: Δ1= ( γ 1-φ1) - ( β 1- α 1); If Δ1 is a negative value, it means that the high-speed end measuring shaft system rotates counterclockwise by an angle of |Δ1|; If Δ1 is a non-negative value, it means that the high-speed end measuring shaft system rotates clockwise by an angle |Δ1|.

[0045] The high-speed end measuring shaft system rotates by an angle Δ1, so that the high-speed end measuring shaft system and the reducer input shaft are in the calibration condition to determine the phase alignment state, where (γ1-φ1) is the phase difference between the high-speed end measuring shaft system in the random state (i.e., the actual state) and the standard connection phase state, ( β 1- α 1) It is the phase difference between the random state and the standard connection phase state of the reducer input.

[0046] S5: After rotating the high-speed end measuring shaft system by Δ1 and connecting it to the reducer input end, it is moved to the test station 16; the high-speed end is positioned and connected to the input side of the reducer adapter under the drive of the guide rail system 15, and is pressed and combined in an inseparable state, and then moved to the test station 16.

[0047] S6: Obtain the phase γ2 of the measuring axis system at the low speed end in the camera coordinate system, and the angle β2 between the horizontal side of the T-shaped mark at the output end of the reducer and the positive direction of the X axis in the camera coordinate system; Similarly, the calculation method of β2 is the same as β1, which will not be repeated here.

[0048] S7: Calculate the rotation angle Δ2 of the measured shaft system at the low speed end according to γ2, β2, φ2 and α2; Furthermore, the calculation formula for measuring the shaft rotation angle Δ2 at the low speed end is: Δ2= ( γ 2-φ2) - ( β 2-α 2).

[0049] If Δ2 is a negative value, it means that the high-speed end measuring shaft system rotates counterclockwise by an angle of |Δ2|; If Δ2 is a non-negative value, it means that the high-speed end measuring shaft system rotates clockwise by an angle |Δ2|.

[0050] S8: Rotate the low-speed end measuring shaft system by Δ2 and connect it to the output end of the reducer to complete the phase connection.

[0051] The guide rail moving system 15 drives the high-speed end and the transported object (the reducer and adapter to be tested) 8 to move to the test station 16 and position and press together with the low-speed end measuring component to realize the phase connection process of the measuring shaft system.

[0052] Move the high-speed end with rotatable power from the test station to the preparation station to assemble the high-speed end and the reducer input end. Since the reducer and its connecting parts do not have rotational power, the high-speed end shaft system is rotated for assembly. Subsequently, the assembled high-speed end and reducer are moved back to the test station, and the low-speed end is rotated after obtaining the rotation angle of the low-speed end shaft system to complete the entire assembly work.

[0053] Further, the slots at the high-speed end, the spline teeth at the input end of the reducer, the slots at the low-speed end, and the spline teeth at the output end of the reducer are numbered respectively; When the high-speed end is connected in phase with the reducer input end, the slot number of the high-speed end is consistent with the number of the spline teeth of the reducer input end: for example, slot No. 1 of the high-speed end is connected with spline No. 1 of the reducer input end, slot No. 2 of the high-speed end is connected with spline No. 2 of the reducer input end... and so on.

[0054] When the low-speed end is phase-connected with the output end of the reducer, the slot number of the low-speed end is consistent with the number of the spline teeth of the output end of the reducer. For example, slot No. 1 of the low-speed end is connected to spline No. 1 of the output end of the reducer, slot No. 2 of the low-speed end is connected to spline No. 2 of the output end of the reducer, and so on.

[0055] After the reducer is assembled, it may be necessary to test the assembly accuracy, and it may be necessary to make corrections after detection. Since there is inevitably a gap in the spline connection, and the internal and external spline teeth and spline grooves with different numbers are combined, that is, the angular error gap caused by the connection of the measuring shaft system at different phases is inconsistent, which brings inconvenience to the angular error compensation. In addition, if the shaft system connection phase is inconsistent, the measurement state of the measured reducer will be different each time due to this difference. Therefore, it is necessary to "real-name" the teeth and grooves of the internal and external splines, that is, when the high-speed end is phase-connected with the reducer input end, the slot number of the high-speed end is consistent with the number of the spline teeth at the reducer input end, and when the low-speed end is phase-connected with the reducer output end, the slot number of the low-speed end is consistent with the number of the spline teeth at the reducer output end, to ensure the connection under a certain phase and realize the uniqueness of the measurement shaft system connection. Since the uniqueness of the connection state between the measuring shaft system in the instrument and the input measuring shaft and output measuring shaft of the measured reducer is ensured, the spline tooth groove gap is determined and unique during each loading and unloading process, further ensuring the accuracy of the detection parameters of the measured reducer.

[0056] The phase of the internal spline in the measurement system is determined by the phase of the circular grating angle measurement system. Therefore, an additional measurement method is needed to associate the phase of the external spline with the phase of the internal spline. The transmission effect produced by the combination of internal and external teeth at different phases is different, especially the impact on the angle measurement accuracy is very different, especially when there is a transmission gap. Therefore, it is necessary to "real-name" the internal and external splines to ensure the connection at a specific phase and realize the uniqueness of the shaft connection.

[0057] In this application, the phase of the shaft system is measured by the high-speed end under standard conditions and actual conditions. 、 The angle between the horizontal side of the T-shaped mark at the input end of the reducer and the positive direction of the X-axis in the camera coordinate system is used to determine the technical solution for measuring the rotation angle of the shaft system at the high-speed end and the rotation angle of the shaft system at the low-speed end. In fact, it is not limited to the structure of spline connection. In theory, it can also be applied to the assembly of other connection methods.

[0058] It should be noted that the terms used in this application are only for describing specific embodiments, rather than limiting the scope of this application. As shown in the specification of this application, unless the context clearly indicates an exception, the words "one", "a", "a kind of" and / or "the" do not specifically refer to the singular, but may also include the plural. The terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method or device. In the absence of more restrictions, the elements defined by the sentence "include one..." do not exclude the presence of other identical elements in the process, method or device including the elements.

[0059] It should also be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. Unless otherwise clearly specified and limited, the terms "installed", "connected", "coupled", etc. should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0060] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the technical solutions of the embodiments of the present application.

Claims

1. A method for determining phase connection of a measuring shaft system based on visual guidance, characterized in that: The steps include: S1: T-shaped marks are etched at the input and output ends of the reducer respectively; the size of the T-shaped marks satisfies the following relationship: L h = k1×D; L v = k2×D, and L v / L h = m; W = k3×(D / P) n ×D; |L v - L h |≤ΔL; Among them, L h Indicates the horizontal length of the T-shaped logo, L v represents the length of the vertical side of the T-shaped mark, D represents the outer diameter of the spline, P represents the pitch of the spline, k1, k2, k3 are proportional coefficients, m is the proportional constant, n is the exponential factor, W represents the width of the horizontal side of the T-shaped mark, and ΔL represents the preset length difference threshold; S2: Under the standard connection phase state, the high-speed end measures the shaft phase φ1, the angle α1 between the horizontal side of the T-shaped mark at the reducer input end and the positive direction of the X-axis in the camera coordinate system, and the low-speed end measures the shaft phase φ2, and the angle α2 between the horizontal side of the T-shaped mark at the reducer output end and the positive direction of the X-axis in the camera coordinate system; S3: Move the high-speed end to the preparation station, obtain the phase γ1 of the high-speed end measurement axis system in the camera coordinate system and the angle β1 between the horizontal side of the T-shaped mark at the reducer input end and the positive direction of the X axis in the camera coordinate system; S4: Calculate the rotation angle Δ1 of the measuring shaft system at the high-speed end according to γ1, β1, φ1 and α1; S5: Rotate the high-speed end measuring shaft system by Δ1, connect it to the reducer input end, and then move it to the test station; S6: Obtain the phase γ2 of the measuring axis system at the low speed end in the camera coordinate system, and the angle β2 between the horizontal side of the T-shaped mark at the output end of the reducer and the positive direction of the X axis in the camera coordinate system; S7: Calculate the rotation angle Δ2 of the measured shaft system at the low speed end according to γ2, β2, φ2 and α2; S8: Rotate the low-speed end measuring shaft system by Δ2 and connect it to the output end of the reducer to complete the phase connection.

2. The method for determining phase connection of a measuring shaft system based on vision guidance according to claim 1 is characterized in that: The calculation formula for measuring the shaft rotation angle Δ1 at the high-speed end is: Δ1= ( γ 1-φ1) - ( β 1- α 1); If Δ1 is a negative value, it means that the high-speed end measuring shaft system rotates counterclockwise by an angle of |Δ1|; If Δ1 is a non-negative value, it means that the high-speed end measuring shaft system rotates clockwise by an angle |Δ1|.

3. The method for determining phase connection of measuring shaft system based on vision guidance according to claim 1 is characterized in that: The calculation formula for measuring the shaft rotation angle Δ2 at the low speed end is: Δ2= ( γ 2-φ2) - ( β 2- α 2); If Δ2 is a negative value, it means that the low-speed end measuring shaft system rotates counterclockwise by an angle of |Δ2|; If Δ2 is a non-negative value, it means that the measured shaft system at the low-speed end rotates clockwise by an angle |Δ2|.

4. The method for determining phase connection of measuring shaft system based on vision guidance according to claim 1 is characterized in that: In the standard connection phase state, the method for obtaining the angle α1 between the horizontal side of the T-shaped mark at the reducer input end and the positive direction of the X-axis in the camera coordinate system is: The T-shaped mark at the input end of the reducer is photographed by a camera vision measurement system to obtain a first image; Identify the edge of the T-shaped mark in the first image, perform binarization processing, obtain the edges of the horizontal and vertical sides of the T-shaped mark, and fit the straight line equations of the two sides in the camera coordinate system; Select two points A and B on the same side of the vertical edge of the T-shaped mark, and calculate the difference δ between the two points in the Y direction; According to the slope k and δ of the straight line equation of the vertical side of the T-shaped mark and the acute angle θ between the horizontal side of the T-shaped mark and the positive direction of the X-axis (zero phase) in the camera coordinate system, determine the angle α1 between the horizontal side of the T-shaped mark at the input end of the reducer and the positive direction of the X-axis in the camera coordinate system.

5. The method for determining phase connection of measuring shaft system based on vision guidance according to claim 4 is characterized in that: According to the slope k and δ of the straight line equation of the vertical side of the T-shaped mark and the acute angle θ between the horizontal side of the T-shaped mark and the positive direction of the X-axis (zero phase) in the camera coordinate system, the angle α1 between the horizontal side of the T-shaped mark at the input end of the reducer and the positive direction of the X-axis in the camera coordinate system is determined as follows: If the slope k of the equation of the vertical side of the T-shaped marker is less than 0 and δ>0, then α1=θ; If the slope k of the equation of the vertical side of the T-shaped marker is less than 0 and δ<0, then α1=180º+θ; If the slope k of the equation of the vertical side of the T-shaped marker is greater than 0 and δ>0, then α1=360º-θ; If the slope k of the equation of the vertical side of the T-shaped marker is greater than 0 and δ<0, then α1=180º-θ.

6. The method for determining phase connection of measuring shaft system based on vision guidance according to claim 1 is characterized in that: Obtain the angle β1 between the horizontal side of the T-shaped mark at the reducer input end and the positive direction of the X-axis in the camera coordinate system, including: The T-shaped mark at the input end of the reducer is photographed by a camera vision measurement system to obtain a second image; Identify the edge of the T-shaped mark in the second image, perform binarization processing, obtain the edges of the horizontal and vertical sides of the T-shaped mark, and fit the straight line equations of the two sides in the camera coordinate system; Select two points A` and B` on the same side of the vertical edge of the T-shaped mark, and calculate the difference δ` between the two points in the Y direction; According to the slope k`, δ` of the straight line equation of the vertical side of the T-shaped mark and the acute angle θ` between the horizontal side of the T-shaped mark and the positive direction of the X-axis (zero phase) in the camera coordinate system, determine the angle β1 between the horizontal side of the T-shaped mark at the input end of the reducer and the positive direction of the X-axis in the camera coordinate system.

7. The method for determining phase connection of measuring shaft system based on vision guidance according to claim 6 is characterized in that: According to the slope k', δ' of the straight line equation of the vertical side of the T-shaped mark and the acute angle θ' between the horizontal side of the T-shaped mark and the positive direction of the X-axis (zero phase) in the camera coordinate system, the angle β1 between the horizontal side of the T-shaped mark at the input end of the reducer and the positive direction of the X-axis in the camera coordinate system is determined as follows: If the slope k` of the equation of the vertical side of the T-shaped marker is less than 0 and δ`>0, then β1=θ`; If the slope k` of the equation of the vertical side of the T-shaped marker is less than 0 and δ`<0, then β1=180º+θ`; If the slope k` of the equation of the vertical side of the T-shaped marker is greater than 0 and δ`>0, then β1=360º-θ`; If the slope k` of the equation of the vertical side of the T-shaped marker is greater than 0 and δ`<0, then β1=180º-θ`.

8. The method for determining phase connection of measuring shaft system based on vision guidance according to claim 1 is characterized in that: Also includes: Number the slots at the high speed end, the spline teeth at the reducer input end, the slots at the low speed end, and the spline teeth at the reducer output end respectively; When the high-speed end is phase-connected with the reducer input end, the slot number of the high-speed end is consistent with the number of the spline teeth of the reducer input end; When the low-speed end is phase-connected with the output end of the reducer, the slot number of the low-speed end is consistent with the number of the spline teeth of the output end of the reducer.

9. The method for determining phase connection of measuring shaft system based on vision guidance according to claim 1 is characterized in that: The horizontal width W of the T-shaped logo is not less than the preset width threshold W min .

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