Non-contact grating positioning measurement platform and method

Abstract

The invention relates to the technical field of grating detection, in particular to a non-contact grating positioning measurement platform and method.The non-contact grating positioning measurement platform is mainly composed of an axial distance measuring probe, a radial distance measuring probe, a multi-dimensional displacement adjusting table, an air floating rotary table and a control system; in the process that the air floating rotary table drives the grating to rotate, the axial distance measuring probe and the radial distance measuring probe periodically measure the distance between the axial distance measuring probe and the grating, and the control system generates an end jump error curve and an eccentric error curve according to measured data and controls the multi-dimensional displacement adjusting table in a closed-loop mode according to the end jump error curve and the eccentric error curve. And adjusting the levelness of the upper surface of the to-be-processed grating and the overlap ratio of the circle center of the to-be-processed grating and the rotation center. Non-contact measurement in the grating machining process is achieved, the problem that the grating can be damaged by traditional contact measurement is solved, and the method has extremely high application value in the actual machining process.

Description

Technical Field

[0001] The invention belongs to the technical field of grating detection, and in particular relates to a non-contact grating positioning measurement platform and method. Background Art

[0002] The grating angle encoder is a high-precision angular displacement detection device, which mainly consists of an encoder reading head and a grating. The grating is a metal ring processed from 304 stainless steel, or a coated glass ring-shaped flat sheet. The grating line coding pattern of the metal grating is engraved on the outer cylindrical surface of the grating mirror, and the grating line coding pattern of the glass code disk is engraved on the grating end face. As the accuracy reference of the encoder, the grating has high requirements for the roundness of the circular grating and the center positioning before the grating line is engraved. Traditional roundness measurement and eccentricity positioning solutions mostly use contact measurement, such as roundness meter, three-coordinate, inductive distance meter and lever micrometer. However, the hardness of the reflective coating of 304 stainless steel and glass code disk is relatively low, and the above contact measurement solution will cause irreversible surface damage. It affects the integrity of the product appearance and affects the user's use and installation.

[0003] Therefore, a non-contact grating positioning measurement solution is urgently needed to prevent the grating from being scratched by contact measurement tools. Summary of the invention

[0004] In view of this, the present invention aims to provide a non-contact grating positioning measurement platform and method, which obtains the end jump error and eccentricity error of the grating through non-contact nanometer-level axial ranging probe and radial ranging probe, and adjusts the multi-dimensional displacement adjustment table carrying the grating accordingly, eliminating the eccentricity and uneven upper surface problems caused by the placement of the grating position, and avoiding the problem of contact measurement tools scratching the grating surface during the traditional grating adjustment process.

[0005] To achieve the above object, the technical solution created by the present invention is implemented as follows: The invention provides a non-contact grating positioning and measuring platform, including: an axial distance measuring probe, a radial distance measuring probe, a multi-dimensional displacement adjustment platform, an air-floating turntable and a control system; The multi-dimensional displacement adjustment platform is used to support and adjust the grating to be processed, and is arranged on the air-floating turntable; the air-floating turntable is used to drive the multi-dimensional displacement adjustment platform and the grating to be processed to rotate; The axial distance measuring probe is arranged above the multi-dimensional displacement adjustment table, and the distance measuring direction of the axial distance measuring probe is in the vertical direction. The axial distance measuring probe is used to periodically measure the vertical distance between the axial distance measuring probe and the grating to be processed; The radial distance measuring probe is arranged in the circumference of the multi-dimensional displacement adjustment table, and the distance measuring direction of the radial distance measuring probe is in the horizontal direction. The radial distance measuring probe is used to periodically measure the horizontal distance between it and the grating to be processed; The control system is used to record the vertical distance and the horizontal distance, and generate the end jump error curve and the eccentricity error curve. The multi-dimensional displacement adjustment table is regulated according to the end jump error curve so that the horizontality of the upper surface of the grating to be processed meets the preset requirements; the horizontal position of the grating to be processed is adjusted according to the eccentricity error curve so that the coincidence degree between the center of the circle of the grating to be processed and the rotation center meets the preset requirements.

[0006] Preferably, both the axial distance measuring probe and the radial distance measuring probe are nanometer-scale non-contact distance measuring probes.

[0007] Preferably, both the axial distance measuring probe and the radial distance measuring probe are fixed by a magnetic universal arm.

[0008] Preferably, the control system is a host computer software for data visualization.

[0009] Preferably, the multi-dimensional displacement adjustment platform is an automatic displacement platform or a manual displacement platform.

[0010] Another aspect of the present invention provides a non-contact grating positioning measurement method, which uses a non-contact grating positioning measurement platform to adjust the grating to be processed, comprising: The air-floating turntable is controlled to rotate at a constant speed, and the control system controls the axial distance measuring probe and the radial distance measuring probe to measure the distance at a set frequency respectively, and feeds back the measured vertical distance data and horizontal distance data to the control system; The control system calculates and outputs an end jump error curve and an eccentricity error curve, wherein the abscissa of the end jump error curve is the absolute angle of the air-floating turntable, and the ordinate of the end jump error curve is the difference between the vertical distance measured by the axial distance measuring probe and the preset vertical standard distance; the abscissa of the eccentricity error curve is the absolute angle of the air-floating turntable, and the ordinate of the eccentricity error curve is the difference between the horizontal distance measured by the radial distance measuring probe and the preset horizontal standard distance; The pitch angle of the multi-dimensional displacement adjustment stage is regulated according to the end jump error curve; Adjust the horizontal position of the grating to be processed according to the eccentricity error curve.

[0011] Preferably, it also includes: after the horizontality of the upper surface of the grating to be processed and the degree of coincidence between the center of the circle of the grating to be processed and the rotation center are adjusted to meet preset requirements, the adjusted horizontal distance between the grating and the grating to be processed is measured by a radial ranging probe, and the horizontal cross-sectional shape of the grating to be processed is obtained by fitting based on the measured horizontal distance data, and then the roundness of the grating to be processed is calculated.

[0012] Preferably, the multi-dimensional displacement adjustment platform is an automatic displacement platform, and the adjustment process is: automatically adjusting the inclination angle of the multi-dimensional displacement adjustment platform according to the end jump error curve so that the horizontality of the upper surface of the grating to be processed meets the preset requirements; According to the eccentricity error curve, the horizontal position of the grating to be processed is adjusted by the multi-dimensional displacement adjustment table, and the coincidence degree between the center of the grating to be processed and the rotation center meets the preset requirements. Preferably, the multi-dimensional displacement adjustment stage is a manual displacement stage, and the adjustment process is: adjusting the multi-dimensional displacement adjustment stage according to the ordinate ratio of two adjacent wave peaks on the end jump error curve; after the adjustment, re-measuring the end jump error curve, and adjusting the multi-dimensional displacement adjustment stage again according to the ordinate ratio of two adjacent wave peaks on the new end jump error curve, repeating the above adjustment process until the end jump error curve converges and the horizontality of the upper surface of the grating to be processed meets the preset requirements, then stopping the manual adjustment; The horizontal position of the grating to be processed is changed through the multi-dimensional displacement adjustment table according to the ordinate ratio of two adjacent peaks on the eccentricity error curve; after adjustment, the eccentricity error curve is re-measured, and the horizontal position of the grating to be processed is adjusted again according to the ordinate ratio of two adjacent peaks on the new eccentricity error curve, and the above adjustment process is repeated until the eccentricity error curve converges and the coincidence degree between the center of the grating to be processed and the rotation center meets the preset requirements, then the manual adjustment is stopped.

[0013] Compared with the prior art, the invention can achieve the following beneficial effects: The present invention provides a non-contact grating positioning measurement solution, which uses a non-contact high-precision distance measuring probe to perform measurement, thereby avoiding physical damage to the grating surface, protecting the appearance and precision of the grating, and correcting the end jump error and eccentricity error of the grating according to the measurement data, thereby achieving high-precision positioning of the grating and improving the precision of subsequent processing processes.

[0014] The control system of the present invention is integrated in the host computer software. Through the dedicated host computer software, digital recording and management of data can be realized, which is convenient for data integration and subsequent process improvement. In addition, the host computer software provides an intuitive user interface, including an error curve interface, angle position information, extreme angle position and error size information, etc., which is convenient for users to perform data analysis and adjustment.

[0015] After grating positioning measurement and correction, the measuring platform of the present invention can also fit the side figure of the grating, calculate the grating roundness, and record the grating intrinsic roundness, run-out value, and its product ID, production date, shift, batch and other information, thereby achieving product traceability and facilitating quality tracking and after-sales service. The measuring platform has been verified by actual tests and has extremely high practical value. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings constituting part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments and descriptions of the present invention are used to explain the present invention and do not constitute an improper limitation on the present invention. In the drawings: Figure 1 is a structural diagram of a non-contact grating positioning and measuring platform provided according to an embodiment of the present invention; Figure 2 is an eccentricity error curve diagram provided according to an embodiment of the present invention; Figure 3 The diagram is a definable and editable data management interface diagram of the host computer software provided according to an embodiment of the present invention.

[0017] Reference numerals include: Radial distance measuring probe 1, axial distance measuring probe 2, grating to be processed 3, multi-dimensional displacement adjustment table 4, air-floating turntable 5. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical scheme and advantages of the invention clearer, the invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the invention and do not constitute a limitation to the invention. Similar components in different embodiments use associated similar component numbers. In the following embodiments, many detailed descriptions are to enable the invention to be better understood. However, those skilled in the art can easily recognize that some of the features can be omitted in different situations, or can be replaced by other components, materials, and methods. In some cases, some operations related to the invention are not shown or described in the specification, in order to avoid the core part of the invention being overwhelmed by too much description, and for those skilled in the art, it is not necessary to describe these related operations in detail, and they can fully understand the related operations according to the description in the specification and the general technical knowledge in the art.

[0019] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other to form various implementation methods. At the same time, the steps or actions in the method description can also be interchanged or adjusted in a manner that is obvious to those skilled in the art. Therefore, the various sequences in the specification and the drawings are only for the purpose of clearly describing a certain embodiment and are not meant to be a necessary sequence, unless otherwise specified that a certain sequence must be followed.

[0020] In the description of the invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the invention and simplifying the description, rather than indicating or implying 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 invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the invention, unless otherwise specified, the meaning of "multiple" is two or more.

[0021] In the description of the invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" 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 indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the invention can be understood according to specific circumstances.

[0022] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0023] See also Figure 1In one embodiment of the present invention, a non-contact grating positioning and measuring platform is proposed, which is used to perform high-precision positioning on the grating 3 to be processed, so that the horizontality and concentricity of the upper plane of the grating 3 to be processed meet the preset requirements, and the subsequent processing accuracy is guaranteed. It can be understood that the grating 3 to be processed is a grating blank that has been preliminarily processed, usually in the shape of a disk, a ring or a cylinder, and its material is a common encoder grating manufacturing substrate such as metal or glass. The grating 3 to be processed itself has a high roundness and surface flatness. During the detection process, it is mainly to ensure that the upper surface of the grating 3 to be processed has a high level relative to the horizontal plane, and solve the problem that after the grating 3 to be processed is placed on the multi-dimensional displacement adjustment table 4, the placement angle of the grating 3 to be processed causes a large end jump on the upper surface of the grating 3 to be processed during the rotation process. In addition, concentricity refers to the physical center of the grating 3 to be processed (i.e., the center of the upper surface circle) and the rotation center are highly coincident, so as to avoid the occurrence of engraving errors during the processing. In the traditional grating processing and measurement process, devices such as roundness meters, three-coordinate measuring machines, inductive distance meters, and lever-type micrometers are used to measure the placement error of the grating 3 to be processed on the processing table. Since the contact part of the measuring equipment (such as the probe and the measuring head) is in direct contact with the surface of the grating 3 to be processed, physical damage may be caused to the surface of the grating 3 to be processed during the rotation process. In particular, for the grating 3 to be processed made of 304 stainless steel and glass, the hardness of the reflective coating of these materials is relatively low, and they are more susceptible to damage from contact measuring equipment, resulting in surface damage. This damage not only affects the appearance integrity of the grating, but may also affect its accuracy and performance, thereby affecting the processing quality and reliability of the final product. Therefore, these traditional contact measurement schemes have gradually shown their limitations in the field of modern precision processing, especially in the processing of high-precision gratings. Therefore, the embodiments of the present invention are designed as follows Figure 1The non-contact grating positioning and measuring platform shown in the figure is designed with corresponding measuring and correction methods. The platform structure includes: radial ranging probe 1, axial ranging probe 2, multi-dimensional displacement adjustment platform 4, air-floating turntable 5 and control system, wherein radial ranging probe 1 and axial ranging probe 2 are data measuring devices. Since the measurement requirements of general high-precision gratings are at the micron level, the radial ranging probe 1 and axial ranging probe 2 of the present invention both adopt high-precision nanometer-level non-contact laser ranging probes to ensure that the measurement accuracy can meet the processing requirements, and are connected and spatially positioned by magnetic universal arms respectively. Specifically, the radial ranging probe 1 and the axial ranging probe 2 are both provided with a corresponding magnetic universal arm, and the structures of the two magnetic universal arms are the same, and both consist of a section of a mechanical arm with multiple degrees of freedom and a magnetic seat. And the way that the magnetic universal arm connects the radial ranging probe 1 and the axial ranging probe 2 is the same. The following is only taken as an example to illustrate the connection method of the radial ranging probe 1. One end of the mechanical arm is connected to the radial ranging probe 1, and the other end is connected to the magnetic seat. The radial ranging probe 1 can be fixed to the processing station through the magnetic seat. Similarly, the axial ranging probe 2 is also fixed to the processing station by the magnetic universal arm. After the radial ranging probe 1 and the axial ranging probe 2 are fixed, it is necessary to adjust the ranging direction to facilitate subsequent error measurement. Under normal circumstances, the ranging direction of the radial ranging probe 1 can be adjusted to the horizontal direction using tools such as theodolite, and aligned with the side of the grating 3 to be processed placed on the multi-dimensional displacement adjustment table 4. The ranging direction of the axial ranging probe 2 is adjusted to the vertical direction, and aligned with the upper surface of the grating 3 to be processed placed on the multi-dimensional displacement adjustment table 4. The ranging point is located as close to the edge of the upper surface of the grating 3 to be processed as possible to ensure that the axial ranging probe 2 can more sensitively obtain the end face runout of the grating 3 to be processed.

[0024] The multi-dimensional displacement adjustment platform 4 is a support and position adjustment platform for the grating 3 to be processed. The multi-dimensional displacement adjustment platform 4 can realize multi-dimensional movement and pitch angle adjustment. In the measurement platform of the present invention, the multi-dimensional displacement adjustment platform 4 can adopt either an automatic displacement platform or a manual displacement platform. The difference between the two is only in the subsequent correction process. The main measurement targets in the measurement process are: the position accuracy of the grating 3 to be processed placed on the multi-dimensional displacement adjustment platform 4, that is, the levelness of the upper surface of the grating 3 to be processed relative to the horizontal plane, and the eccentricity (or concentricity) between the physical center and the rotation center of the grating 3 to be processed. The position of the grating 3 to be processed is corrected based on the measured levelness and eccentricity data to ensure that it can meet the processing requirements. When the position accuracy is adjusted, the flatness and roundness data of the grating 3 to be processed can be measured again.

[0025] The grating 3 to be processed is placed on the multi-dimensional displacement adjustment platform 4, which is installed in the rotation center area of ​​the air-floating turntable 5. The air-floating turntable 5 is a high-precision rotating platform based on the principle of gas static pressure support. It uses the air film pressure to support the rotation, realizes frictionless and high-precision rotation movement, and can drive the grating 3 to be processed and the multi-dimensional displacement adjustment platform 4 to rotate smoothly, so as to facilitate subsequent all-round measurement.

[0026] The control system is used for whole machine control and data processing. It is composed of dedicated host computer software, which is electrically connected with radial distance measuring probe 1, axial distance measuring probe 2, multi-dimensional displacement adjustment platform 4, and air-floating turntable 5 through a communication interface to form a closed loop. During the measurement process, the air-floating turntable 5 drives the grating 3 to be processed and the multi-dimensional displacement adjustment platform 4 to rotate at a constant speed, and the control system controls the radial distance measuring probe 1 and the axial distance measuring probe 2 to perform light ranging. During the rotation of the air-floating turntable 5, the host computer software will send a pulse signal with a fixed frequency. According to the sampling density set by the host computer software, the radial distance measuring probe 1 and the axial distance measuring probe 2 will record the current relative distance with the grating 3 to be processed, that is, the horizontal distance and the vertical distance, after receiving a fixed number of pulse signals, and record the absolute angle of the current air-floating turntable 5 at the same time. After the air-floating turntable 5 rotates one circle, the complete eccentricity error curve and the end jump error curve can be obtained according to the horizontal distance and the vertical distance obtained by the acquisition.

[0027] The horizontal coordinate of the eccentricity error curve is the absolute angle of the air-floating turntable 5, and the vertical coordinate of the eccentricity error curve is the difference between the horizontal distance measured by the radial distance measuring probe 1 and the preset horizontal standard distance. The horizontal coordinate of the end jump error curve is the absolute angle of the air-floating turntable 5, and the vertical coordinate of the end jump error curve is the difference between the vertical distance measured by the axial distance measuring probe 2 and the preset vertical standard distance.

[0028] The eccentricity error curve and the end jump error curve are both approximately sinusoidal curves. It can be understood that when the processing error of the grating 3 to be processed itself, that is, the surface flatness, is not considered, the eccentricity error curve and the end jump error curve should theoretically be sinusoidal curves or error-free straight lines. According to the eccentricity error curve and the end jump error curve obtained by the collection, the multi-dimensional displacement adjustment table 4 can be controlled to correct the grating 3 to be processed at different angles, so that the horizontality of the upper surface of the grating 3 to be processed meets the preset requirements, and the coincidence degree between the center of the circle of the grating 3 to be processed and the rotation center meets the preset requirements, and finally the adjustment result is verified to complete the correction of eccentricity and end jump.

[0029] Based on the above platform structure, the embodiment of the present invention also provides a method for performing non-contact grating positioning measurement using the platform structure, and adjusting the grating position according to the measurement result, which specifically includes the following steps: The air-floating turntable 5 is controlled to rotate at a constant speed. At the same time, the radial distance measuring probe 1 and the axial distance measuring probe 2 are controlled to perform light distance measurement according to a preset frequency, and the vertical distance and horizontal distance data obtained are fed back to the host computer software. The host computer software calculates the output end jump error curve and the eccentricity error curve according to the measured data. Figure 2 As shown in the figure, it is the eccentricity error curve obtained in the actual test process, the horizontal axis of which is the absolute angle of the air-floating turntable 5, the dimension is degree; the vertical axis is the difference between the horizontal distance measured by the radial distance measuring probe 1 and the preset horizontal standard distance, the dimension is micrometer. Similarly, the horizontal axis of the end jump error curve represents the absolute angle of the air-floating turntable 5, the dimension is degree; the vertical axis represents the difference between the vertical distance measured by the axial distance measuring probe 2 and the preset vertical standard distance, the dimension is micrometer.

[0030] After obtaining the end jump error curve and the eccentricity error curve, the pitch angle and position of the multi-dimensional displacement adjustment table 4 are adjusted to correct the upper surface level of the grating 3 to be processed and the coincidence between the center of the circle of the grating 4 to be processed and the rotation center. Specifically, when the multi-dimensional displacement adjustment table 4 is an automatic displacement table, the inclination angle of the multi-dimensional displacement adjustment table 4 can be automatically adjusted according to the end jump error curve to achieve the preset upper surface level. It can be understood that if the multi-dimensional displacement adjustment table 4 has automatic adjustment capability, the control system can control the multi-dimensional displacement adjustment table 4 to adjust the pitch angle at the angle position where the end jump error is the largest, that is, the highest peak or the lowest trough of the curve, through the end jump error curve, and adjust the maximum error amount at one time, so that the automatic correction of the horizontality can be completed in a single time. Similarly, according to the eccentricity error curve, the control system can control the multi-dimensional displacement adjustment table 4 to move in the horizontal direction at the angle position where the eccentricity error is the largest, and the movement amount is the maximum eccentricity error, and the automatic correction of the concentricity can also be completed in a single time.

[0031] When the multi-dimensional displacement adjustment stage 4 is a manual displacement stage, a technician needs to perform manual calibration. Since manual calibration cannot be accurately adjusted in a single time, multiple iterative adjustments are required to make the radial ranging probe 1 and the axial ranging probe 2 converge respectively, that is, both change to a straight line close to y=0. The manual adjustment process is as follows: First, the ordinate ratio of two adjacent peaks on the end jump error curve is selected as the adjustment value to adjust the pitch angle of the multi-dimensional displacement adjustment stage 4. The selected two peaks preferably include the peak with the largest ordinate.

[0032] After the first adjustment is completed, the end jump error curve is re-measured, and the ordinate ratio of two adjacent peaks on the new end jump error curve is adjusted again. According to the above process, the end jump error curve is measured and adjusted repeatedly until the end jump error curve converges and the upper surface levelness of the grating 3 to be processed meets the preset requirements.

[0033] The correction process of the eccentricity error is basically the same as that of the end jump error. Specifically, the ordinate ratio of two adjacent peaks on the eccentricity error curve is selected as the adjustment value, and the horizontal position of the multi-dimensional displacement adjustment stage 4 is manually changed to adjust the horizontal position of the grating 3 to be processed. Similarly, the eccentricity error curve is re-measured, and the horizontal position of the multi-dimensional displacement adjustment stage 4 is adjusted according to the ordinate ratio of two adjacent peaks on the new eccentricity error curve, thereby adjusting the horizontal position of the grating 3 to be processed. This process also needs to be repeated until the eccentricity error curve converges and the coincidence between the center of the grating 3 to be processed and the rotation center reaches the preset requirement.

[0034] At this point, the position error measurement and correction of the grating 3 to be processed are completed. The grating 3 to be processed can be measured again by the radial distance measuring probe 1 and the axial distance measuring probe 2 to obtain the end jump error curve and the eccentricity error curve after error correction. The small-scale irregular fluctuations in the end jump error curve can be regarded as the processing error of the upper surface of the grating 3 to be processed, and the data can be recorded. The small-scale irregular fluctuations in the eccentricity error curve can be regarded as the processing error of the side of the grating 3 to be processed. The horizontal cross-sectional shape of the grating 3 to be processed can be obtained by fitting the eccentricity error curve, and the roundness of the grating to be processed can be calculated, and the data can also be recorded.

[0035] In the embodiment of the present invention, the measured end jump error curve and eccentricity error curve can be stored in the database of the host computer software, and a single result can be defined to be retained, such as Figure 3 The figure shows the definable editable data management interface of the host computer software. Finally, the jump error curve and eccentricity error curve measured after the position error correction reflect the processing error, fitting graph, roundness data, etc. of the upper surface of the processing grating 3, which can be used as the exit information of each product and the user's large model database, and can be used as the basis for subsequent mechanical finishing, realizing the dataization of processing technology and quality management, and also facilitating later maintenance.

[0036] In short, the above description is only a preferred embodiment of this specification and is not intended to limit the protection scope of this specification. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this specification shall be included in the protection scope of this specification.

[0037] The systems, devices, modules or units described in one or more of the above embodiments may be implemented by a computer chip or entity, or by a product having a certain function. A typical implementation device is a computer. Specifically, the computer may be, for example, a personal computer, a laptop computer, a cellular phone, a camera phone, a smart phone, a personal digital assistant, a media player, a navigation device, an email device, a game console, a tablet computer, a wearable device, or a combination of any of these devices.

[0038] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0039] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0040] The above is a description of a specific embodiment of the specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the embodiments and still achieve the desired results. In addition, the processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

Claims

1. A non-contact grating positioning and measuring platform, characterized in that: include: Axial distance measuring probe, radial distance measuring probe, multi-dimensional displacement adjustment table, air-floating turntable and control system; The multi-dimensional displacement adjustment platform is used to support and adjust the grating to be processed, and is arranged on the air-floating turntable; the air-floating turntable is used to drive the multi-dimensional displacement adjustment platform and the grating to be processed to rotate; The axial distance measuring probe is arranged above the multi-dimensional displacement adjustment platform, and the distance measuring direction of the axial distance measuring probe is in the vertical direction, and the axial distance measuring probe is used to periodically measure the vertical distance between the axial distance measuring probe and the grating to be processed; The radial distance measuring probe is arranged in the circumference of the multi-dimensional displacement adjustment platform, and the distance measuring direction of the radial distance measuring probe is in the horizontal direction. The radial distance measuring probe is used to periodically measure the horizontal distance between the radial distance measuring probe and the grating to be processed; The control system is used to record the vertical distance and the horizontal distance, and generate an end jump error curve and an eccentricity error curve. The multi-dimensional displacement adjustment table is regulated according to the end jump error curve so that the horizontality of the upper surface of the grating to be processed meets the preset requirements; the horizontal position of the grating to be processed is adjusted according to the eccentricity error curve so that the coincidence degree between the center of the grating to be processed and the rotation center meets the preset requirements.

2. The non-contact grating positioning and measuring platform according to claim 1, characterized in that: The axial distance measuring probe and the radial distance measuring probe are both nanometer-level non-contact distance measuring probes.

3. The non-contact grating positioning and measuring platform according to claim 1, characterized in that: The axial distance measuring probe and the radial distance measuring probe are both fixed by a magnetic universal arm.

4. The non-contact grating positioning and measuring platform according to claim 1, characterized in that: The control system is a host computer software for data visualization.

5. The non-contact grating positioning and measuring platform according to claim 1, characterized in that: The multi-dimensional displacement adjustment platform is an automatic displacement platform or a manual displacement platform.

6. A non-contact grating positioning measurement method, characterized in that: The method of adjusting the grating to be processed by using the non-contact grating positioning and measuring platform as claimed in any one of claims 1 to 4 comprises: The air-floating turntable is controlled to rotate at a constant speed, and the control system controls the axial distance measuring probe and the radial distance measuring probe to measure distance at set frequencies respectively, and feeds back the measured vertical distance data and horizontal distance data to the control system; The control system calculates and outputs an end jump error curve and an eccentricity error curve, wherein the abscissa of the end jump error curve is the absolute angle of the air-floating turntable, and the ordinate of the end jump error curve is the difference between the vertical distance measured by the axial distance measuring probe and the preset vertical standard distance; the abscissa of the eccentricity error curve is the absolute angle of the air-floating turntable, and the ordinate of the eccentricity error curve is the difference between the horizontal distance measured by the radial distance measuring probe and the preset horizontal standard distance; Adjusting the pitch angle of the multi-dimensional displacement adjustment platform according to the end jump error curve; Adjust the horizontal position of the grating to be processed according to the eccentricity error curve.

7. The non-contact grating positioning measurement method according to claim 6, characterized in that: Also includes: After the horizontality of the upper surface of the grating to be processed and the degree of coincidence between the center of the circle of the grating to be processed and the rotation center are adjusted to meet the preset requirements, the radial ranging probe is used to measure the adjusted horizontal distance between it and the grating to be processed, and the horizontal cross-sectional shape of the grating to be processed is obtained by fitting based on the measured horizontal distance data, and then the roundness of the grating to be processed is calculated.

8. The non-contact grating positioning measurement method according to claim 6, characterized in that: The multi-dimensional displacement adjustment platform is an automatic displacement platform, and the adjustment process is: automatically adjusting the inclination angle of the multi-dimensional displacement adjustment platform according to the end jump error curve so that the horizontality of the upper surface of the grating to be processed meets the preset requirements; The horizontal position of the grating to be processed is adjusted by the multi-dimensional displacement adjustment table according to the eccentricity error curve, and the coincidence degree between the center of the grating to be processed and the rotation center meets the preset requirements.

9. The non-contact grating positioning measurement method according to claim 6, characterized in that: The multi-dimensional displacement adjustment platform is a manual displacement platform, and the adjustment process is: adjusting the multi-dimensional displacement adjustment platform according to the ordinate ratio of two adjacent peaks on the end jump error curve; After the adjustment, the end jump error curve is measured again, and the multi-dimensional displacement adjustment stage is adjusted again according to the ordinate ratio of two adjacent peaks on the new end jump error curve. The above adjustment process is repeated until the end jump error curve converges and the horizontality of the upper surface of the processed grating meets the preset requirements, then the manual adjustment is stopped; The horizontal position of the grating to be processed is changed by the multi-dimensional displacement adjustment table according to the ratio of the longitudinal coordinates of two adjacent peaks on the eccentricity error curve; after the adjustment, the eccentricity error curve is re-measured, and the horizontal position of the grating to be processed is adjusted again according to the ratio of the longitudinal coordinates of two adjacent peaks on the new eccentricity error curve, and the above adjustment process is repeated until the eccentricity error curve converges and the coincidence degree between the center of the grating to be processed and the rotation center meets the preset requirements, then the manual adjustment is stopped.

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