A curved surface standard for calibrating large-size non-contact measuring equipment and a calibration method thereof

Abstract

The present invention discloses a curved surface standard for calibration of large-scale non-contact measuring equipment and a calibration method. The curved surface standard comprises a quadratic body, a horizontal displacement platform, and a vertical lifting frame. The quadratic body comprises a concave curved surface panel and a convex curved surface panel. The outer edges of the concave curved surface panel and the convex curved surface panel are provided with uniformly distributed standard balls. The surfaces of the concave curved surface panel, the convex curved surface panel and the standard balls are all matte-finished. The horizontal displacement platform is used to adjust the distance between the measuring equipment to be calibrated and the quadratic body in the horizontal direction. The installation direction of the horizontal displacement platform points to the center direction of the quadratic body. The vertical lifting frame is installed on the horizontal displacement platform and can be displaced in the horizontal direction. The vertical lifting frame is used to install the measuring equipment and adjust the position of the measuring equipment in the vertical direction to ensure the centering relationship between the measuring equipment and the quadratic body. The present invention can realize the calibration of the contour scanning measurement error of large-scale non-contact measuring equipment.

Description

Technical Field

[0001] The invention belongs to the technical field of geometric measurement, and relates to a curved surface standard for calibration of large-size non-contact measurement equipment and a calibration method. Background Art

[0002] With the continuous development of national industrialization, more and more large-scale metrology equipment has been gradually put into the daily production process of enterprises and institutions in various industries. As a kind of large-scale measurement, non-contact measurement is increasingly widely used, such as laser radar, ground scanners and laser tracking scanners. At the same time, the calibration demand for related equipment is also increasing day by day. At present, there are some surface standards on the market that are used for the calibration of contour scanning measurement errors of large-scale non-contact measurement equipment, and some application progress has been made.

[0003] The standard device used for the calibration of contour scanning measurement errors of large-scale non-contact measuring equipment mainly includes the following methods.

[0004] One is to make a standard spherical or parabolic standard with a small metal material, with a matte effect on the surface of the curved surface. At the same time, standard balls with different distances are arranged along the surface or edge of the curved surface, and the surface of the standard balls is made of matte material. The actual parameters of the surface and the position distance between different standard balls are calibrated by a three-coordinate measuring machine, which are used as reference values ​​for calibration. That is, the corresponding standard is scanned by a laser radar or scanner, and the instrument contour scanning measurement error is calibrated by measuring the distance between the ball centers. The disadvantage of this implementation form is that the equipment is relatively simple, and the geometric size of the surface is often greatly limited due to the design of portability. Therefore, it cannot meet the functional requirements of some equipment for scanning and calibrating larger surfaces.

[0005] The second is to achieve calibration by processing large-scale curved surface standard devices. This is mainly done by building large-scale curved surface standard devices in factories or large laboratories, completing the construction of large curved surfaces by splicing multiple surfaces, calibrating the contour shape with contact measurement equipment such as laser trackers, and then using laser radars or scanners to scan the corresponding standards. The instrument contour scanning measurement error is calibrated through the contour measurement of large curved surfaces. The disadvantages of this implementation form are that the equipment is large, the establishment process is relatively complicated, it is not convenient to move the measurement position, and measurements can only be performed at fixed positions. The equipment under test needs to be moved multiple times to achieve calibration at different depths of field. Summary of the invention

[0006] The main purpose of the present invention is to provide a curved surface standard for calibration of large-scale non-contact measuring equipment and a calibration method, which can realize the contour scanning measurement error calibration of large-scale non-contact measuring equipment, and has the advantages of compact and reliable structure, high adjustment accuracy, wide application range, automatic realization of multi-distance measurement process, and high measurement efficiency.

[0007] One aspect of the present invention provides a curved surface standard for calibrating a large-scale non-contact measuring device, comprising a quadratic surface body, a horizontal displacement platform, and a vertical lifting frame.

[0008] The quadratic curved body comprises a rotating table, a mounting frame, a standard ball, a concave curved panel, and a convex curved panel. The rotating table can realize 360° rotation. The bottom of the mounting frame is connected to the rotating table. The front and rear surfaces above are respectively connected and fixed to the concave curved panel and the convex curved panel, so as to concentrically fix the concave curved panel and the convex curved panel on the same axis. The outer edges of the concave curved panel and the convex curved panel are provided with uniformly distributed standard balls. The surfaces of the concave curved panel, the convex curved panel and the standard ball are all matte-treated.

[0009] The horizontal displacement platform is used to adjust the distance between the measuring device to be calibrated and the quadratic body in the horizontal direction, and the installation direction of the horizontal displacement platform points to the center direction of the quadratic body;

[0010] The vertical lifting frame is installed on the horizontal displacement platform and can be displaced in the horizontal direction. The vertical lifting frame is used to install the measuring device and adjust the position of the measuring device in the vertical direction to ensure the centering relationship between the measuring device and the quadratic surface body.

[0011] Preferably, the quadratic curved surface body further includes a supporting column, a locking handle, a handle bracket, and a rotating bearing.

[0012] The bottom of the support column is fixed on the ground, a rotary bearing is installed above the support column, the rotating platform is installed above the rotating bearing, and the rotating platform can realize 360° rotation through the rotating bearing;

[0013] Two handle brackets are installed on both sides of the top of the supporting column, and a locking handle is fixedly installed on each handle bracket to lock the rotating platform.

[0014] Preferably, the horizontal displacement platform includes a horizontal base, a horizontal slide, a horizontal motor, a horizontal gear, a horizontal guide rail, and a horizontal rack.

[0015] The horizontal base is made of metal or marble, the bottom of the horizontal base is installed on the ground, and the installation direction of the horizontal base points to the center direction of the quadratic surface body;

[0016] A horizontal guide rail and a horizontal rack are installed above the horizontal base. The horizontal slide is installed on the horizontal guide rail and can slide freely along the horizontal guide rail. A horizontal motor is installed on one side of the horizontal slide. A horizontal gear is installed on the horizontal motor for cooperating with the horizontal rack to realize gear and rack drive.

[0017] Preferably, the horizontal displacement platform further includes a horizontal shim, a magnetic scale, a magnetic scale reading head, and a slider.

[0018] The bottom of the horizontal base is leveled and installed on the ground through a plurality of horizontal shims, the slider is installed on the horizontal guide rail, and the horizontal slide is installed on the slider, and can slide freely along the horizontal guide rail through the slider;

[0019] A magnetic scale is installed above the horizontal base, and a magnetic scale reading head is installed at the middle bottom of the horizontal slide, which is used to confirm the displacement of the horizontal slide by reading the data of the magnetic scale.

[0020] Preferably, the vertical lifting frame includes a vertical guide rail, a vertical slide, a vertical gear, a vertical motor, a vertical rack, and a vertical base frame;

[0021] The vertical base frame is installed on the horizontal slide. A vertical guide rail and a vertical rack are installed on the vertical surface of the vertical base frame close to the quadratic surface body. The vertical slide is installed on the vertical guide rail. A vertical motor is installed on one side of the vertical slide. The vertical gear is installed on the output shaft of the vertical motor. The up and down movement of the vertical slide is achieved through the relative movement of the vertical gear and the vertical rack.

[0022] Preferably, the vertical lifting frame further comprises a wire sensor, an instrument support plate, and a wire fixing block;

[0023] The pull-wire sensor is fixed at the bottom of one side of the vertical base frame above the horizontal slide, and the movable end of the pull-wire sensor is fixed on the pull-wire fixing block on the side of the vertical slide, which is used to measure the displacement of the vertical slide moving up and down. The instrument support plate is installed under the vertical slide for installing and fixing the measuring equipment.

[0024] Another aspect of the present invention provides a calibration method for a large-size non-contact measuring device, which uses the above-mentioned curved surface standard device to calibrate the contour scanning measurement error, comprising:

[0025] The quadratic body is placed at a position 1.5 to 2 times the distance measurement blind area of ​​the measuring device, so that the area scanned by the measuring device satisfies a projection angle of not less than 30°, and the concave curved surface panel and the convex curved surface panel of the quadratic body are scanned respectively;

[0026] Adjust the placement distance between the measuring device and the quadratic surface by driving the horizontal slide table for at least 3 times, with each interval being no less than 3m, and repeat the scanning without changing the scanning area;

[0027] When the installation distance is greater than the focal length, the projection angle is allowed to be less than 30°. The data obtained by the scanning of the measuring device is optimally fitted with the models of the concave curved surface panel and the convex curved surface panel to obtain the curved surface profile, and the profile deviation is calculated by comparing with the reference value;

[0028] The maximum value of the profile deviation obtained by scanning the concave curved panel and the convex curved panel is taken as the profile scanning measurement error to realize the calibration of the measuring equipment.

[0029] The curved surface standard and calibration method for calibrating large-scale non-contact measuring equipment according to the above aspects of the present invention can realize the calibration of contour scanning measurement errors of large-scale non-contact measuring equipment, and has the advantages of compact and reliable structure, high adjustment accuracy, wide application range, automatic realization of multi-distance measurement process, and high measurement efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solution of the present invention, the following briefly introduces the drawings used in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work:

[0031] Figure 1 It is a schematic diagram of the main structure of a curved surface standard for calibrating a large-size non-contact measuring device according to an embodiment of the present invention;

[0032] Figure 2 is a schematic structural diagram of a quadratic body according to an embodiment of the present invention;

[0033] Figure 3 is a schematic structural diagram of a horizontal displacement platform according to an embodiment of the present invention;

[0034] Figure 4 is a schematic structural diagram of a vertical lifting frame according to an embodiment of the present invention;

[0035] Figure 5 is a working schematic diagram of a curved surface standard device according to an embodiment of the present invention;

[0036] Among them: 1-quadratic surface body, 2-vertical lifting frame, 3-horizontal displacement platform, 4-measuring equipment, 5-support column, 6-locking handle, 7-handle bracket, 8-rotating bearing, 9-turntable, 10-mounting back frame, 11-standard ball, 12-concave curved surface panel, 13-convex curved surface panel, 14-horizontal base, 15-horizontal shim, 16-magnetic scale, 17-magnetic scale reading head, 18-slider, 19-horizontal slide, 20-horizontal motor, 21-horizontal gear, 22-horizontal guide rail, 23-horizontal rack, 24-pull wire sensor, 25-vertical guide rail, 26-instrument tray, 27-pull wire fixing block, 28-vertical slide, 29-vertical gear, 30-vertical motor, 31-vertical rack, 32-vertical base frame. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] The embodiment of the present invention provides a curved surface standard for calibrating a large-scale non-contact measuring device, wherein the measuring device to be calibrated includes a laser radar, a laser scanner, etc. Figure 1 As shown, a quadratic surface standard device according to an embodiment of the present invention includes a quadratic surface body 1 , a horizontal displacement platform 3 , and a vertical lifting frame 2 .

[0039] The quadratic body 1 is used as the measured body of the entire standard instrument. The whole is composed of multiple matte-finished surfaces, with a compact and concentrated structure, which is convenient for the measuring equipment to quickly collect its surface data. At the same time, it can achieve 360° horizontal angle adjustment, which is convenient for switching between different surfaces. The horizontal displacement platform 3 is made of metal or marble. It is a device for adjusting the distance relationship between the measuring equipment and the quadratic body 1 in the horizontal direction. Its installation direction points to the center direction of the quadratic body 1. It can effectively adjust the measurement distance through electric control to ensure the quick implementation of the calibration work. The vertical lifting frame 2 is installed on the horizontal displacement platform 3 and can be displaced in the horizontal direction. At the same time, it can install the measuring equipment 4 and adjust its position in the vertical direction to ensure the centering relationship between different measuring equipment and the quadratic body 1.

[0040] like Figure 2As shown, the quadratic curved body includes a support column 5, a locking handle 6, a handle support seat 7, a rotating bearing 8, a rotating platform 9, a mounting frame 10, a standard ball 11, a concave curved panel 12, and a convex curved panel 13. The bottom of the support column 5 is connected and fixed to the ground foundation, and a rotating bearing 8 is installed on the top of the support column 5. A rotating platform 9 is installed on the top of the rotating bearing 8, and the rotating platform 9 can achieve 360° rotation through the rotating bearing 8. Two handle support seats 7 are installed on both sides of the top of the support column 5, and a locking handle 6 can be installed and fixed on each handle support seat 7 to lock the rotating platform 9 to ensure that it is fixed and positioned after rotating to a suitable position. A mounting frame 10 is installed on the top of the rotating platform 9, and the bottom of the mounting frame 10 is connected to the rotating platform 9 through a connecting flange, and the front and rear surfaces of the top are respectively connected and fixed to the concave curved panel 12 and the convex curved panel 13, so as to fix the two concentrically on the same spatial axis. The concave curved panel 12 and the convex curved panel 13 are parabolic surfaces with a diameter greater than or equal to 1 meter. Standard balls 11 of equal size are evenly distributed around their outer edges. The surfaces of the concave curved panel 12, the convex curved panel 13 and the standard balls 11 are matte-finished to facilitate the measurement equipment 4 to quickly collect their surface data.

[0041] During installation, the support column 5 below the quadratic curved body 1 is installed on the ground foundation below through the bottom flange, the rotating bearing 8 is installed above the supporting column 5 and one circle of it is fixed to the supporting column 5, and the rotating table 9 is placed above the rotating bearing 8 and fixed with its other circle, so that the rotating table 9 can rotate 360° along its central axis; two handle brackets 7 are installed at the two sides of the top of the supporting column 5, and the locking handles 6 are screwed in respectively to realize the locking operation after the rotating table 9 is rotated into place; the mounting back frame 10 is installed above the rotating table 9, and the front and rear sides thereof are respectively installed with a matte-treated concave curved panel 12 and a convex curved panel 13, which are installed in a coaxial manner, which is convenient for the centering operation of the equipment after the curved surface is rotated and switched; a plurality of matte standard balls 11 are evenly installed at the edge positions of the concave curved panel 12 and the convex curved panel 13, which is convenient for assisting the determination of the benchmark and the calibration of the spatial coordinates.

[0042] By using a quadratic curved surface body 1 composed of multiple matte-finished curved surfaces as the measured body of the entire standard instrument, the structure is compact and concentrated, which can not only ensure that the measuring device 4 can quickly collect its surface data, but also can achieve 360° horizontal angle adjustment at the same time. Through the 360-degree rotation range of the rotating table, it can ensure any angle adjustment and switching in the horizontal plane of the concave curved surface panel 12 and the convex curved surface panel 13. Standard balls 11 of equal size are evenly distributed around the outer edge of the concave curved surface panel 12 and the convex curved surface panel 13. The structure is compact, and the surface of the standard ball 11 is also matte-finished as the concave curved surface panel 12 and the convex curved surface panel 13, which can facilitate the measuring device 4 to quickly collect its surface data.

[0043] like Figure 3 As shown, the horizontal displacement platform 3 includes a horizontal base 14, a horizontal shim 15, a magnetic scale 16, a magnetic scale reading head 17, a slider 18, a horizontal slide 19, a horizontal motor 20, a horizontal gear 21, a horizontal guide rail 22, and a horizontal rack 23. The horizontal base 14 is made of metal or marble, and its bottom is leveled and installed on the ground through a plurality of horizontal shims 15. The installation direction of the horizontal base 14 points to the center direction of the quadratic surface body 1. A horizontal guide rail 22, a horizontal rack 23, and a magnetic scale 16 are installed above the horizontal base 14. The horizontal slide 19 is installed on four sliders 18 that can slide freely above the horizontal guide rail 22, and can slide freely along the direction of the horizontal guide rail 22. A horizontal motor 20 is installed on one side of the horizontal slide 19, and a horizontal gear 21 is installed on the horizontal motor 20 to realize the gear rack driving function with the horizontal rack 23. A magnetic scale reading head 17 is installed at the middle bottom of the horizontal slide 19. During the operation of the horizontal slide 19, the displacement can be confirmed and compensated by reading the data of the magnetic scale 16.

[0044] The horizontal displacement platform 3 is installed with a gear rack as the transmission form, and a magnetic scale 16 is used as the measurement standard for closed-loop processing, which can realize the precise positioning and movement of the measuring device 4 in the horizontal direction, and realize the horizontal distance adjustment between the measuring device 4 and the quadratic curved surface 1.

[0045] When installing the horizontal displacement platform 3, the horizontal base 14 made of metal or marble is leveled and installed on the ground through multiple horizontal shims 15. During the installation process, ensure that the installation direction of the horizontal base 14 points to the center direction of the quadratic curved surface body 1; install the guiding horizontal guide rail 22, the horizontal rack 23 for transmission, and the magnetic scale 16 as a standard on the upper surface of the horizontal base 14 respectively; then install the horizontal slide 19 on the slider 18 on the horizontal guide rail 22 so that it can slide freely along the direction of the horizontal guide rail 22; install the horizontal motor 20 on one side of the horizontal slide 19, and install the horizontal gear 21 on the horizontal motor 20 to realize the gear rack drive function with the horizontal rack 23; install the magnetic scale reading head 17 at the middle bottom of the horizontal slide 19, so that the data of the magnetic scale 16 can be read in real time during the operation of the horizontal slide 19, confirm the size of the displacement and implement corresponding compensation.

[0046] By using metal or marble as the main material of the horizontal base 14, the horizontal displacement platform 3 is installed in the direction of the center of the quadratic body 1, and the distance relationship between the measuring device 4 and the quadratic body 1 in the horizontal direction is effectively adjusted by electric control. The position compensation is implemented by measuring the distance with the magnetic scale 16, which can realize automatic position adjustment after multiple measurements of different distances or conversion of different devices, thereby ensuring the quick implementation of the calibration work.

[0047] like Figure 4As shown, the vertical lifting frame 2 includes a wire sensor 24, a vertical guide rail 25, an instrument support plate 26, a wire fixing block 27, a vertical slide 28, a vertical gear 29, a vertical motor 30, a vertical rack 31, and a vertical base frame 32. The vertical base frame 32 is installed on the horizontal slide 19, and a vertical guide rail 25 and a vertical rack 29 are installed on the side of its vertical vertical surface close to the quadratic body 1. The vertical guide rail 25 is used to guide the up and down movement. The vertical slide 28 is installed on the vertical guide rail 25, and a vertical motor 30 is installed on one side to realize the up and down movement drive. The vertical gear 29 is installed on the output shaft of the vertical motor 30, and the vertical rack 31 is installed on the side of the vertical base frame 32 close to one side of the quadratic body 1. The transmission function of the vertical slide 28 moving up and down is realized through the relative movement of the vertical gear 29 and the vertical rack 31. The wire sensor 24 is fixed to the bottom of one side of the vertical base frame 32 above the horizontal slide 19, and its movable end is fixed to the wire fixing block 27 on the side of the vertical slide 28. When the vertical slide 28 moves up and down, the displacement of the up and down movement is measured by the wire sensor 24. The instrument support plate 26 is installed under the vertical slide 28 for installing and fixing the measuring device 4.

[0048] When installing the vertical lifting frame 2, the vertical base frame 32 of its main structure is installed on the horizontal slide 19, and the vertical guide rail 25 and the vertical rack 29 are installed on the side of the vertical base frame 32 near the quadratic surface body 1, and the vertical rack 31 is installed outside. The vertical guide rail 25 realizes the up and down guiding function, and the vertical rack 31 is used to ensure transmission; then the vertical slide 28 is installed on the vertical guide rail 25, and the vertical motor 30 is installed on one side of the vertical slide 28 to realize the electric control of the vertical slide 28 to move up and down; the vertical gear 29 is installed on the output shaft of the vertical motor 30 , the transmission function of the vertical slide 28 moving up and down is realized through the relative movement of the vertical gear 29 and the vertical rack 31; the wire sensor 24 is fixed to the bottom of one side of the vertical base frame 32 above the horizontal slide 19, and then its movable end is fixed to the wire fixing block 27 on the side of the vertical slide 28, so as to ensure that during the up and down movement of the vertical slide 28, the wire sensor 24 can measure the up and down displacement of the vertical slide 28 in real time and implement compensation; finally, the instrument tray 26 is installed under the vertical slide 28, and after it is firmly fixed, the measuring device 4 is installed on the instrument tray 26.

[0049] The vertical lifting frame 2 adopts gear rack as the transmission form and uses the wire sensor 24 as the measurement standard for closed-loop processing. It can realize the precise positioning and movement of the measuring device 4 in the vertical direction and the height alignment adjustment of the measuring device 4 and the quadratic curved surface body 1. A universal interface is set on it to install a variety of different devices, and the calibration requirements of different types of equipment can be met through height adjustment.

[0050] The vertical lifting frame 2 installed on the horizontal slide 28 can not only realize the displacement of the measuring device 4 in the horizontal direction, but also drive the measuring device 4 to adjust its position in the vertical direction and implement position compensation with the wire sensor 24, thereby ensuring the centering relationship between different measuring devices and the quadratic curved surface 1.

[0051] When the curved surface standard device of the embodiment of the present invention is working, Figure 5 As shown, firstly, the measuring device 4 is installed on the instrument support plate 26 on the vertical slide 28, and the vertical gear 29 is driven by the vertical motor 30 to realize the vertical drive. The vertical slide 28 drives the measuring device 4 to move up and down in the vertical direction. At the same time, the pull-wire sensor 24 measures the displacement of the vertical slide 28 in real time and implements compensation to complete the centering process of the measuring device 4 and the quadratic curved surface body 1; loosen the locking handle 6, rotate the rotating table 9 to rotate it along the axial direction, so that one of the concave curved surface panel 12 and the convex curved surface panel 13 is first aligned with the direction of the measuring device 4, and then tighten the locking handle 6; then drive the horizontal motor 20 on the horizontal displacement platform 3 to drive the horizontal gear 21, so that the horizontal slide 19 moves along the horizontal guide rail 22, thereby driving the measuring device 4 on the vertical lifting frame 2 to realize horizontal movement, that is, adjust the position relationship between the measuring device 4 and the quadratic curved surface body 1, and the next calibration work can be started after the adjustment is completed.

[0052] To sum up, the curved surface standard in the embodiment of the present invention is installed with two different matte concave and convex surfaces, a concave curved surface panel and a convex curved surface panel, and evenly distributed matte balls, which can meet different measurement needs; at the same time, through the 360-degree rotation range of the rotating table, the adjustment and switching of any angle within the horizontal plane of the concave and convex surfaces can be guaranteed; a horizontal displacement platform is configured, and gear racks are used as the transmission form. A magnetic scale is used as the measurement standard for closed-loop processing, which can realize the precise positioning and movement of the measuring equipment in the horizontal direction, and realize the horizontal distance adjustment between the measuring equipment and the quadratic curved surface body; a vertical lifting frame is configured, and gear racks are used as the transmission form. A pull-wire sensor is used as the measurement standard for closed-loop processing, which can realize the precise positioning and movement of the measuring equipment in the vertical direction, and realize the height alignment adjustment between the measuring equipment and the quadratic curved surface body.

[0053] The embodiment of the present invention also provides a calibration method for a large-scale non-contact measurement device, using the curved surface standard device of the above embodiment to calibrate the contour scanning measurement error. During calibration, the concave curved surface panel 12 and the convex curved surface panel 13 are the objects to be measured, and the target is scanned and measured at a position 1.5 to 2 times the measurement blind area of ​​the measuring device 4. The measurement data is best fitted with the standard curved surface model, and the difference between the obtained curved surface profile and its reference value is the contour scanning measurement error of the device.

[0054] The calibration process of the calibration method of the embodiment of the present invention is as follows: the quadratic body 1 is placed at a position 1.5 to 2 times the distance measurement blind area of ​​the measuring device 4, so that the area scanned by the measuring device 4 satisfies the projection angle α or β of not less than 30°, and the concave and convex surfaces of the quadratic body 1 are scanned respectively. The placement distance of the scanner from the quadratic body 1 is adjusted by driving the horizontal slide 19 for no less than 3 times, each time with an interval of not less than 3m, but the scanning area is not changed, and the scanning is repeated. When the placement distance is greater than the focal length, α and β are allowed to be less than 30°. The scanning data is optimally fitted with the digital model of the concave / convex surface panel to obtain the contour of the standard surface, and the contour deviation is calculated. The maximum value of the contour deviation obtained by measuring the concave surface and the convex surface is taken as the contour scanning measurement error, thereby realizing the calibration process of the relevant equipment.

[0055] The curved surface standard and calibration method for calibrating large-scale non-contact measuring equipment in the above-mentioned embodiments of the present invention effectively solve the problems that most existing curved surface standards cannot meet large-range measurement requirements due to their small size, the separation configuration of concave and convex surfaces is not compact enough, the measurement distance cannot be accurately adjusted, the installation of different equipment is relatively complicated and the measurement efficiency is reduced due to height adjustment. The curved surface standard has the advantages of compact and reliable structure, high adjustment accuracy, wide application range, automatic realization of multi-distance measurement process, and high measurement efficiency.

[0056] The above description is only by way of illustration of certain exemplary embodiments of the present invention. It is undoubted that those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A curved surface standard for calibrating large-scale non-contact measuring equipment, characterized in that: It includes a quadratic surface, a horizontal displacement platform, and a vertical lifting frame. The quadratic curved body comprises a rotating table, a mounting frame, a standard ball, a concave curved panel, and a convex curved panel. The rotating table can realize 360° rotation. The bottom of the mounting frame is connected to the rotating table. The front and rear surfaces above are respectively connected and fixed to the concave curved panel and the convex curved panel, so as to concentrically fix the concave curved panel and the convex curved panel on the same axis. The outer edges of the concave curved panel and the convex curved panel are provided with uniformly distributed standard balls. The surfaces of the concave curved panel, the convex curved panel and the standard ball are all matte-treated. The horizontal displacement platform is used to adjust the distance between the measuring device to be calibrated and the quadratic body in the horizontal direction, and the installation direction of the horizontal displacement platform points to the center direction of the quadratic body; The vertical lifting frame is installed on the horizontal displacement platform and can be displaced in the horizontal direction. The vertical lifting frame is used to install the measuring device and adjust the position of the measuring device in the vertical direction to ensure the centering relationship between the measuring device and the quadratic surface body; The horizontal displacement platform includes a horizontal base, a horizontal slide, a horizontal motor, a horizontal gear, a horizontal guide rail, and a horizontal rack. The horizontal base is made of metal or marble, the bottom of the horizontal base is installed on the ground, and the installation direction of the horizontal base points to the center direction of the quadratic surface body; A horizontal guide rail and a horizontal rack are installed above the horizontal base, the horizontal slide is installed on the horizontal guide rail and can slide freely along the horizontal guide rail, a horizontal motor is installed on one side of the horizontal slide, and a horizontal gear is installed on the horizontal motor for cooperating with the horizontal rack to realize gear rack drive; The horizontal displacement platform also includes a horizontal shim, a magnetic scale, a magnetic scale reading head, and a slider. The bottom of the horizontal base is leveled and installed on the ground through a plurality of horizontal shims, the slider is installed on the horizontal guide rail, and the horizontal slide is installed on the slider, and can slide freely along the horizontal guide rail through the slider; A magnetic scale is installed above the horizontal base, and a magnetic scale reading head is installed at the middle bottom of the horizontal slide, which is used to confirm the displacement of the horizontal slide by reading the data of the magnetic scale; The distance relationship between the measuring device and the quadratic body in the horizontal direction is effectively adjusted by electric control, and position compensation is implemented by the magnetic scale distance measurement method, so that automatic position adjustment can be achieved after multiple different distance measurements or conversion of different devices; The vertical lifting frame includes a vertical guide rail, a vertical slide, a vertical gear, a vertical motor, a vertical rack, and a vertical base frame; The vertical base frame is installed on the horizontal slide, a vertical guide rail and a vertical rack are installed on the vertical vertical surface of the vertical base frame close to the quadratic surface body, the vertical slide is installed on the vertical guide rail, a vertical motor is installed on one side of the vertical slide, and a vertical gear is installed on the output shaft of the vertical motor, and the vertical slide is moved up and down by the relative movement of the vertical gear and the vertical rack; The vertical lifting frame also includes a wire sensor, an instrument support plate, and a wire fixing block; The wire sensor is fixed to the bottom of one side of the vertical base frame above the horizontal slide, and the movable end of the wire sensor is fixed to the wire fixing block on the side of the vertical slide, which is used to measure the displacement of the vertical slide up and down, and the instrument support plate is installed under the vertical slide, which is used to install and fix the measuring equipment; The vertical lifting frame adopts rack and pinion as the transmission form, and uses the wire sensor as the measurement standard for closed-loop processing, which can realize the precise positioning and movement of the measuring equipment in the vertical direction, and realize the height alignment adjustment between the measuring equipment and the quadratic curved surface. A universal interface is provided thereon to install a variety of different equipment, and the calibration requirements of different types of equipment can be met through height adjustment.

2. The curved surface standard according to claim 1, characterized in that: The quadratic curved surface body also includes a supporting column, a locking handle, a handle bracket, and a rotating bearing. The bottom of the support column is fixed on the ground, a rotary bearing is installed above the support column, the rotating platform is installed above the rotating bearing, and the rotating platform can realize 360° rotation through the rotating bearing; Two handle brackets are installed on both sides of the top of the supporting column, and a locking handle is fixedly installed on each handle bracket to lock the rotating platform.

3. A calibration method for large-scale non-contact measuring equipment, using the curved surface standard device according to claim 1 or 2 to calibrate the contour scanning measurement error, characterized in that: include: The quadratic body is placed at a position 1.5 to 2 times the distance measurement blind area of ​​the measuring device, so that the area scanned by the measuring device satisfies a projection angle of not less than 30°, and the concave curved surface panel and the convex curved surface panel of the quadratic body are scanned respectively; Adjust the placement distance between the measuring device and the quadratic surface by driving the horizontal slide table for at least 3 times, with each interval being no less than 3m, and repeat the scanning without changing the scanning area; When the installation distance is greater than the focal length, the projection angle is allowed to be less than 30°. The data obtained by the scanning of the measuring device is optimally fitted with the models of the concave curved surface panel and the convex curved surface panel to obtain the curved surface profile, and the profile deviation is calculated by comparing with the reference value; The maximum value of the profile deviation obtained by scanning the concave curved panel and the convex curved panel is taken as the profile scanning measurement error to realize the calibration of the measuring equipment.

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