Bearing surface appearance automatic detection device based on laser point cloud and detection method thereof

Abstract

The invention relates to a laser point cloud-based bearing surface morphology automatic detection device and a detection method. The device comprises a laser scanning and lifting device, a rotating device, a calibration device, a feeding device and a PLC. The laser scanning and lifting device, the rotating device and the calibration device are all installed on the feeding device, and the PLC is electrically connected with electric control parts on the laser scanning and lifting device, the rotating device, the calibration device and the feeding device. The method has the advantages that the point cloud data of the surface of the bearing are obtained through accurate laser scanning, and automatic measurement and data acquisition and storage are achieved in combination with advanced image processing and data analysis algorithms. The system is optimized through the calibration process, so that the reliability and stability of the measurement precision are ensured. The system is simple in structure, easy to operate, high in measurement precision and reliability, capable of effectively reducing labor cost and improving production efficiency, low in manufacturing cost, high in practical application and popularization value and suitable for the field of large-scale production and precision manufacturing.

Description

Technical Field

[0001] The present invention belongs to the technical field of surface morphology detection based on laser point cloud, and in particular relates to a bearing surface morphology automatic detection device based on laser point cloud and a detection method thereof. Background Art

[0002] In the machinery manufacturing and processing industry, bearings are important mechanical parts, and their surface quality directly affects the operating performance of mechanical equipment. At present, the detection methods of bearing surface morphology mainly adopt artificial visual detection, contact detection and non-contact optical detection. Among them, although artificial visual detection is intuitive, it is cumbersome to operate and easily affected by human factors, and the detection accuracy and efficiency are low; the contact detection method may cause damage to the bearing surface during the detection process, and the measurement range is limited; although the non-contact optical detection method can avoid damage caused by contact, it often has problems of low measurement accuracy and slow speed in the measurement of complex surface morphology.

[0003] In recent years, with the development of laser point cloud technology, the application of laser scanning in surface morphology detection has gradually attracted attention. Laser point cloud technology can efficiently obtain high-precision surface data, but in practical applications, how to quickly and accurately automate the detection of bearing surfaces, especially the processing of complex surface morphology, is still a big challenge. In addition, existing laser point cloud data processing methods usually require a lot of manual intervention, and there is still much room for improvement in detection accuracy, real-time performance and automation. Summary of the invention

[0004] In order to solve the above problems, the purpose of the present invention is to provide a bearing surface morphology automatic detection device and a detection method based on laser point cloud.

[0005] In order to achieve the above-mentioned purpose, the automatic detection device of bearing surface morphology based on laser point cloud provided by the present invention includes a laser scanning and lifting device, a rotating device, a calibration device, a feeding device and a PLC; wherein the feeding device includes a connecting block, an A linear guide rail, a workbench, a push-pull cylinder, a feeding slide and a slide plate; the feeding slide is installed in the middle of the top surface of the workbench; two A linear guide rails are installed in parallel on the front and rear end edges of the top of the feeding slide; the slide plate is installed on the two A linear guide rails in a sliding manner, and a connecting block is installed on one end surface; one end of the cylinder body of the push-pull cylinder is fixed to the middle of one side of the feeding slide, and the other end is fixed to the workbench, and the outer end of the gas rod is connected to the connecting block;

[0006] The rotating device comprises a bearing fixture, an electric rotating platform, a rotating platform coupling and a rotating motor; the electric rotating platform is mounted on the top surface of the slide plate, and is provided with a mutually meshing worm gear mechanism inside; the rotating motor is mounted on the outer surface of the electric rotating platform, and the output end is connected to one end of the worm gear through the rotating platform coupling; the lower end of the bearing fixture is mounted on the worm gear of the electric rotating platform, and the upper end adopts a three-jaw centering chuck to clamp and self-center the bearing component to be tested;

[0007] The calibration device comprises a B gantry frame and an optical calibration plate; the lower end of the B gantry frame is fixed to an edge of one side of the top surface of the workbench; the optical calibration plate is installed in the middle of the inner side surface of the B gantry frame;

[0008] The laser scanning and lifting device includes a lifting motor, a grating ruler, a gantry frame A, a laser displacement sensor suspension device, a laser displacement sensor, a position sensor plate, a screw connecting plate, a position sensor, a limit plate, a lifting module, a screw coupling and a screw fixing plate; the lower end of the A gantry frame is fixed to the edge of the other side of the top surface of the workbench; the lifting module includes a module frame, a B linear guide rail and a ball screw; wherein the module frame is installed in the middle of the inner side surface of the A gantry frame; the B linear guide rail is vertically installed on one side of the interior of the module frame; the ball screw is rotatably arranged on the other side of the interior of the module frame through the screw fixing plate; the lifting motor is installed on the top of the module frame, and the output shaft at the lower end is connected to the upper end of the ball screw through the screw coupling; the grating ruler is vertically installed on one side of the module frame to measure the height of the feedback laser displacement sensor; the three position sensors are connected to the upper end of the module frame through the screw coupling. The position sensor plates are installed on the other side of the module frame from top to bottom, corresponding to the mark position, the starting measurement position and the ending measurement position respectively, so as to facilitate the use of PLC to control the position of the laser displacement sensor; the inner side of the lead screw connecting plate is mounted on the ball screw and at the same time slides with the B linear guide rail to achieve precise linear displacement. A laser displacement sensor suspension device is installed on the side close to the grating ruler, and a limit plate is provided on the side close to the position sensor. The limit plate is connected to the position sensor by aligning with the groove in the middle of the position sensor. When the limit plate moves to the groove position, the limit plate interacts with the photoelectric element inside the position sensor to generate a photoelectric signal, thereby realizing accurate detection and feedback of the position to avoid misalignment or misoperation of the laser displacement sensor; the laser displacement sensor is installed on the laser displacement sensor suspension device, and corresponds to the position of the grating ruler in front and back;

[0009] The PLC is electrically connected to the controllers of the lifting motor, the grating ruler, the laser displacement sensor, the position sensor, the electric rotating table, the rotating motor and the push-pull cylinder respectively.

[0010] The PLC control system adopts Siemens S7-1200 CPU1212C.

[0011] The laser displacement sensor adopts SICK PR02-P100B25A1 short-range distance sensor.

[0012] The lifting motor adopts JMC 57J1876-447 stepping motor.

[0013] The position sensor adopts OMRON EE-SX671-WR photoelectric sensor.

[0014] The rotating motor adopts Shinano Y07-58D1-17152 stepping motor.

[0015] Magnetic switches are installed at both ends of the cylinder body of the push-pull cylinder for detecting the push-pull state.

[0016] The method for automatically detecting the bearing surface morphology based on laser point cloud provided by the present invention comprises the following steps performed in sequence:

[0017] 1) First, the inspector places the bearing component to be tested on the bearing fixture, and under the control of the PLC, starts the push-pull cylinder to push out the air rod, thereby pushing the slide together with the rotating device on it and the bearing component to be tested to the designated measurement working position;

[0018] 2) Start the lifting motor, thereby driving the ball screw on the lifting module to rotate, and then drive the laser displacement sensor suspension device, the laser displacement sensor and the limit plate to move downward together through the screw connecting plate until the laser displacement sensor reaches the position sensor at the calibration position to start calibration and set the XY zero point;

[0019] 3) After the calibration is completed, the laser displacement sensor is lowered to the position sensor at the starting measurement position to start the measurement. At the same time, the rotating motor is started, and the electric rotating table is used to drive the measured bearing component to rotate horizontally at a uniform speed. The laser displacement sensor simultaneously collects the surface morphology data of the measured bearing component as XY values;

[0020] 4) After measuring the measured bearing component for one circle, the laser displacement sensor continues to move down, and the grating ruler records the downward distance as the Z value. When the laser displacement sensor moves down to the position sensor at the end measurement position, the measurement is terminated, and the rotating motor is stopped at the same time. Then the lifting motor is reversed, the laser displacement sensor rises and returns to the initial position, the air rod on the push-pull cylinder retracts and pulls the slide back, and the automatic measurement process is completed;

[0021] 5) After receiving the XY values ​​collected by the laser displacement sensor, the Z value recorded by the grating ruler, and the rotation speed of the electric rotary table, the PLC performs precise coordinate conversion and fusion on the XY and Z values, and uses the rotation speed to reconstruct the spatial position of each measuring point, ultimately generating an accurate three-dimensional model of the surface of the measured bearing component for further analysis and visualization.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The bearing surface point cloud data is acquired through precise laser scanning, combined with advanced image processing and data analysis algorithms to achieve automatic measurement, data collection and storage. The system is optimized through the calibration process to ensure the reliability and stability of the measurement accuracy. The system has a simple structure, is easy to operate, has high measurement accuracy and reliability, can effectively reduce labor costs and improve production efficiency, and has a low cost. It has strong practical application and promotion value and is suitable for large-scale production and precision manufacturing. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A stereoscopic diagram of the automatic detection device for bearing surface morphology based on laser point cloud provided by the present invention;

[0025] Figure 2 A stereoscopic diagram of the laser scanning and lifting device in the automatic detection device for bearing surface morphology based on laser point cloud provided by the present invention;

[0026] Figure 3 The present invention provides a schematic diagram of the structure of a lifting module in a bearing surface morphology automatic detection device based on laser point cloud;

[0027] Figure 4 A stereoscopic diagram of a rotating device in a bearing surface morphology automatic detection device based on laser point cloud provided by the present invention;

[0028] Figure 5 A stereoscopic diagram of a calibration device in a bearing surface morphology automatic detection device based on laser point cloud provided by the present invention;

[0029] Figure 6 A stereoscopic diagram of a feeding device in a bearing surface morphology automatic detection device based on laser point cloud provided by the present invention;

[0030] Figure 7 This is a control principle block diagram of the bearing surface morphology automatic detection device based on laser point cloud provided by the present invention. DETAILED DESCRIPTION

[0031] The technical scheme of the present invention will be described in detail below in conjunction with the specific embodiments and drawings of the present invention. The embodiments provided are only some examples of the present invention and do not limit the protection scope of the claims. Based on these embodiments, those skilled in the art can derive other embodiments without creative work, and these embodiments are also within the protection scope of the present invention.

[0032] like Figures 1 to 6As shown, the bearing surface morphology automatic detection device based on laser point cloud provided by the present invention includes a laser scanning and lifting device 1, a rotating device 2, a calibration device 3, a feeding device 4 and a PLC; wherein, the feeding device 4 includes a connecting block 401, a linear guide rail 402, a workbench 403, a push-pull cylinder 404, a feeding slide 405 and a slide plate 406; the feeding slide 405 is installed in the middle of the top surface of the workbench 403; two linear guide rails 402 are installed in parallel on the front and rear end edges of the top of the feeding slide 405; the slide plate 406 is installed on the two linear guide rails 402 in a sliding manner, and a connecting block 401 is installed on one end surface; one end of the cylinder body of the push-pull cylinder 404 is fixed to the middle of one side of the feeding slide 405, and the other end is fixed to the workbench 403, and the outer end of the gas rod is connected to the connecting block 401;

[0033] The rotating device 2 includes a bearing fixture 202, an electric rotating platform 203, a rotating platform coupling 204 and a rotating motor 205; the electric rotating platform 203 is mounted on the top surface of the slide plate 406, and is provided with a mutually meshing worm gear mechanism inside; the rotating motor 205 is mounted on the outer surface of the electric rotating platform 203, and the output end is connected to one end of the worm through the rotating platform coupling 204; the lower end of the bearing fixture 202 is mounted on the worm gear of the electric rotating platform 203, and the upper end adopts a three-jaw centering chuck to clamp and self-center the bearing component 201 to be tested;

[0034] The calibration device 3 includes a B gantry frame 301 and an optical calibration plate 302; the lower end of the B gantry frame 301 is fixed to the edge of one side of the top surface of the workbench 403; the optical calibration plate 302 is installed in the middle of the inner side surface of the B gantry frame 301;

[0035] The laser scanning and lifting device 1 includes a lifting motor 101, a grating ruler 102, an A gantry frame 103, a laser displacement sensor suspension device 104, a laser displacement sensor 105, a position sensor plate 106, a lead screw connecting plate 107, a position sensor 108, a limit plate 109, a lifting module 110, a lead screw coupling 111 and a lead screw fixing plate 112; the lower end of the A gantry frame 103 is fixed to the other side edge of the top surface of the workbench 403; the lifting module 110 includes a module frame, a B linear guide rail 114 and a roller Ball screw 113; wherein the module frame is installed in the middle of the inner side of the A gantry frame 103; the B linear guide 114 is vertically installed on one side of the module frame; the ball screw 113 is rotatably arranged on the other side of the module frame through the screw fixing plate 112; the lifting motor 101 is installed on the top of the module frame, and the output shaft at the lower end is connected to the upper end of the ball screw 113 through the screw coupling 111; the grating ruler 102 is vertically installed on one side of the module frame, which is used to measure the height of the feedback laser displacement sensor 105 ; Three position sensors 108 are installed on the other side of the module frame from top to bottom through the position sensor plate 106, corresponding to the mark position, the starting measurement position and the ending measurement position respectively, so as to facilitate the use of PLC to control the position of the laser displacement sensor 105; the inner side of the lead screw connecting plate 107 is mounted on the ball screw 113 and at the same time slides with the B linear guide 114 to achieve precise linear displacement, a laser displacement sensor suspension device 104 is installed on the side close to the grating ruler 102, and a limit plate 109 is provided on the side close to the position sensor 108, the limit plate 109 is connected to the position sensor 108 by aligning with the groove in the middle of the position sensor 108, when the limit plate 109 moves to the groove position, the limit plate 109 interacts with the photoelectric element inside the position sensor 108 to generate a photoelectric signal, thereby realizing accurate detection and feedback of the position, so as to avoid misalignment or misoperation of the laser displacement sensor 105; the laser displacement sensor 105 is installed on the laser displacement sensor suspension device 104, and corresponds to the position of the grating ruler 102 in front and back;

[0036] The PLC is electrically connected to the controllers of the lifting motor 101 , the grating ruler 102 , the laser displacement sensor 105 , the position sensor 108 , the electric rotating table 203 , the rotating motor 205 and the push-pull cylinder 404 , respectively.

[0037] The PLC control system adopts Siemens S7-1200 CPU1212C.

[0038] The laser displacement sensor 105 is a SICK PR02-P100B25A1 short-range distance sensor.

[0039] The lifting motor 101 adopts a JMC 57J1876-447 stepping motor.

[0040] The position sensor 108 is an OMRON EE-SX671-WR photoelectric sensor.

[0041] The rotating motor 205 adopts Shinano Y07-58D1-17152 stepping motor.

[0042] Magnetic switches are installed at both ends of the cylinder body of the push-pull cylinder 404 for detecting the push-pull state.

[0043] like Figure 7 As shown, the bearing surface morphology automatic detection method based on laser point cloud provided by the present invention comprises the following steps performed in sequence:

[0044] 1) First, the test personnel place the bearing component 201 to be tested on the bearing fixture 202, and under the control of the PLC, start the push-pull cylinder 404 to push out the gas rod, thereby pushing the slide plate 406 together with the rotating device 2 thereon and the bearing component 201 to be tested to the designated measurement working position;

[0045] 2) Start the lifting motor 101, thereby driving the ball screw 113 on the lifting module 110 to rotate, and then drive the laser displacement sensor suspension device 104, the laser displacement sensor 105 and the limit plate 109 to move downward together through the screw connecting plate 107, until the laser displacement sensor 105 reaches the position sensor 108 at the calibration position to start calibration and set the XY zero point;

[0046] 3) After the calibration is completed, the laser displacement sensor 105 is lowered to the position sensor 108 at the starting measurement position to start the measurement. At the same time, the rotating motor 205 is started, and the electric rotating table 203 is used to drive the measured bearing component 201 to rotate horizontally at a uniform speed. The laser displacement sensor 105 simultaneously collects the surface morphology data of the measured bearing component 201 as XY values;

[0047] 4) After measuring the measured bearing component 201 for one circle, the laser displacement sensor 105 continues to move downward, and the grating ruler 102 records the downward movement distance as the Z value. When the laser displacement sensor 105 moves downward to the position sensor 108 at the end measurement position, the measurement is terminated, and the rotating motor 205 is stopped at the same time. Then the lifting motor 101 is reversed, the laser displacement sensor 105 rises and returns to the initial position, and the air rod on the push-pull cylinder 404 retracts to pull the slide plate 406 back, and the automatic measurement process is completed;

[0048] 5) After the PLC receives the XY values ​​collected by the laser displacement sensor 105, the Z value recorded by the grating ruler 102, and the rotation speed of the electric rotating table 203, it performs precise coordinate transformation and fusion on the XY values ​​and the Z values, and uses the rotation speed to reconstruct the spatial position of each measuring point, and finally generates an accurate three-dimensional surface model of the measured bearing component 201 for further analysis and visualization.

Claims

1. A bearing surface morphology automatic detection device based on laser point cloud, characterized in that: The bearing surface morphology automatic detection device based on laser point cloud comprises a laser scanning and lifting device (1), a rotating device (2), a calibration device (3), a feeding device (4) and a PLC; wherein the feeding device (4) comprises a connecting block (401), a linear guide rail (402), a workbench (403), a push-pull cylinder (404), a feeding slide (405) and a slide plate (406); the feeding slide (405) is installed on the workbench (403) The middle part of the top surface; two A linear guide rails (402) are installed in parallel on the front and rear edges of the top of the feeding slide (405); the slide plate (406) is installed on the two A linear guide rails (402) in a sliding manner, and a connecting block (401) is installed on one end surface; one end of the cylinder body of the push-pull cylinder (404) is fixed to the middle part of one side of the feeding slide (405), and the other end is fixed to the workbench (403), and the outer end of the gas rod is connected to the connecting block (401); The rotating device (2) comprises a bearing fixture (202), an electric rotating platform (203), a rotating platform coupling (204) and a rotating motor (205); the electric rotating platform (203) is mounted on the top surface of the slide plate (406), and is provided with a mutually meshing worm gear mechanism inside; the rotating motor (205) is mounted on the outer surface of the electric rotating platform (203), and the output end is connected to one end of the worm gear through the rotating platform coupling (204); the lower end of the bearing fixture (202) is mounted on the worm gear of the electric rotating platform (203), and the upper end adopts a three-jaw centering chuck to clamp and self-center the bearing component (201) to be tested; The calibration device (3) comprises a B gantry frame (301) and an optical calibration plate (302); the lower end of the B gantry frame (301) is fixed to an edge of one side of the top surface of the workbench (403); the optical calibration plate (302) is installed in the middle of the inner side surface of the B gantry frame (301); The laser scanning and lifting device (1) comprises a lifting motor (101), a grating ruler (102), an A gantry frame (103), a laser displacement sensor suspension device (104), a laser displacement sensor (105), a position sensor plate (106), a lead screw connecting plate (107), a position sensor (108), a limit plate (109), a lifting module (110), a lead screw coupling (111) and a lead screw fixing plate (112); the lower end of the A gantry frame (103) is fixed to the other side edge of the top surface of the workbench (403); the lifting module (110) comprises a module frame, a B straight The module frame is installed at the middle of the inner side of the A gantry frame (103); the B linear guide rail (114) is vertically installed on one side of the module frame; the ball screw (113) is rotatably arranged on the other side of the module frame through a screw fixing plate (112); the lifting motor (101) is installed on the top of the module frame, and the output shaft at the lower end is connected to the upper end of the ball screw (113) through a screw coupling (111); the grating ruler (102) is vertically installed on one side of the module frame for measuring the feedback of the laser displacement sensor ( 105); three position sensors (108) are installed on the other side of the module frame from top to bottom through the position sensor plate (106), corresponding to the mark position, the starting measurement position and the ending measurement position respectively, so as to facilitate the use of PLC to control the position of the laser displacement sensor (105); the inner side of the lead screw connecting plate (107) is sleeved on the ball screw (113) and at the same time slides with the B linear guide rail (114) to achieve precise linear displacement, the side close to the grating ruler (102) is equipped with a laser displacement sensor suspension device (104), and the side close to the position sensor (108) is equipped with a laser displacement sensor suspension device (104). A limit plate (109) is provided, and the limit plate (109) is docked with the position sensor (108) by aligning with a groove in the middle of the position sensor (108); when the limit plate (109) moves to the groove position, the limit plate (109) interacts with a photoelectric element inside the position sensor (108) to generate a photoelectric signal, thereby achieving accurate detection and feedback of the position, so as to avoid misalignment or erroneous operation of the laser displacement sensor (105); the laser displacement sensor (105) is installed on the laser displacement sensor suspension device (104), and corresponds to the position of the grating ruler (102) in front and back; The PLC is electrically connected to the controllers of the lifting motor (101), the grating ruler (102), the laser displacement sensor (105), the position sensor (108), the electric rotating table (203), the rotating motor (205) and the push-pull cylinder (404) respectively.

2. The automatic bearing surface morphology detection device based on laser point cloud according to claim 1 is characterized in that: The PLC control system adopts Siemens S7-1200 CPU1212C.

3. The automatic bearing surface morphology detection device based on laser point cloud according to claim 1 is characterized in that: The laser displacement sensor (105) adopts a SICK PR02-P100B25A1 short-range distance sensor.

4. The automatic bearing surface morphology detection device based on laser point cloud according to claim 1 is characterized in that: The lifting motor (101) adopts a JMC 57J1876-447 stepping motor.

5. The automatic bearing surface morphology detection device based on laser point cloud according to claim 1 is characterized in that: The position sensor (108) is an OMRON EE-SX671-WR photoelectric sensor.

6. The automatic bearing surface morphology detection device based on laser point cloud according to claim 1 is characterized in that: The rotating motor (205) is a Shinano Y07-58D1-17152 stepping motor.

7. The automatic bearing surface morphology detection device based on laser point cloud according to claim 1 is characterized in that: Magnetic switches are installed at both ends of the cylinder body of the push-pull cylinder (404) for detecting the push-pull state.

8. A method for detecting bearing surface topography using the automatic device based on laser point cloud according to any one of claims 1 to 7, characterized in that: The detection method comprises the following steps performed in sequence: 1) First, the testing personnel places the bearing component (201) to be tested on the bearing fixture (202), and under the control of the PLC, starts the push-pull cylinder (404) to push out the air rod, thereby pushing the slide plate (406) together with the rotating device (2) thereon and the bearing component (201) to the designated measuring working position; 2) starting the lifting motor (101), thereby driving the ball screw (113) on the lifting module (110) to rotate, and then driving the laser displacement sensor suspension device (104), the laser displacement sensor (105) and the limit plate (109) to move downward together through the screw connecting plate (107), until the laser displacement sensor (105) reaches the position sensor (108) at the calibration position to start calibration and set the XY zero point; 3) After the calibration is completed, the laser displacement sensor (105) is lowered to the position sensor (108) located at the starting measurement position to start measurement, and at the same time, the rotating motor (205) is started, and the electric rotating table (203) is used to drive the measured bearing component (201) to rotate horizontally at a uniform speed, and the laser displacement sensor (105) simultaneously collects surface morphology data of the measured bearing component (201) as XY values; 4) After measuring the measured bearing component (201) for one circle, the laser displacement sensor (105) continues to move downward, and the grating ruler (102) records the downward movement distance as the Z value. When the laser displacement sensor (105) moves downward to the position sensor (108) at the end measurement position, the measurement is terminated, and the rotating motor (205) is stopped at the same time. Then the lifting motor (101) is reversed, the laser displacement sensor (105) rises and returns to the initial position, and the air rod on the push-pull cylinder (404) retracts to pull the slide plate (406) back, and the automatic measurement process is completed; 5) After receiving the XY values ​​collected by the laser displacement sensor (105), the Z value recorded by the grating ruler (102) and the rotation speed of the electric rotating table (203), the PLC performs accurate coordinate conversion and fusion on the XY values ​​and the Z values, and uses the rotation speed to reconstruct the spatial position of each measuring point, and finally generates an accurate three-dimensional model of the surface of the measured bearing component (201) for further analysis and visualization.

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