Method and system for measuring flatness of part through multiple sensors

Abstract

The invention discloses a method and system for measuring the flatness of a part through multiple sensors, and solves the technical problems that the measurement precision is affected, the measurement efficiency is low and the measurement quality is low when the flatness of the part is measured in the prior art. The method comprises the following steps: acquiring N height measurement values of a part at P specified positions by using a sensor group to obtain P groups of height data; wherein the sensor group comprises N sensors which are sequentially arranged in a first direction according to a first interval, and the specified positions are a plurality of positions after the part is sequentially displaced in the first direction according to a second interval; reconstructing the P groups of height data on the same coordinate system, and performing matching processing on the P groups of height data to obtain a coincident flatness line; and the coincident flatness lines are integrated, and the flatness of the part is obtained. According to the invention, measurement errors can be reduced, and measurement precision, measurement efficiency and measurement quality are improved.

Description

Technical Field

[0001] The present invention relates to the field of sensor measurement technology, and in particular to a method and system for measuring the flatness of a part using multiple sensors. Background Art

[0002] In the inspection of some flat parts, flatness measurement is one of the more important measurements, which determines whether the part is a qualified part. At present, the flatness measurement of such parts mainly includes measurement using sensors or collimators.

[0003] Sensor measurement is to set up a platform and a sensor to align with the platform. The part moves on the platform, and the sensor measures the height of each point on the surface of the part. The disadvantage of this measurement method is that when the part is large, a larger platform is required. In this case, the flatness of the platform will affect the measurement of the flatness of the part, resulting in inaccurate measurement, low measurement efficiency and incomplete measurement.

[0004] When using a collimator for measurement, the collimator is usually placed on a base outside the part to be measured, and the reflector is placed on a bridge plate, which is placed on the surface of the part. The bridge plate is used to move the position on the surface of the part, and the collimator measures the readings of each point on the surface of the part, and finally converts them into line values ​​to achieve the measurement of the flatness of the part. Using a collimator to measure the flatness of a part has high measurement accuracy and a large measurement range, but the bridge plate needs to be moved repeatedly. If there is an error in the position movement or it is not moved in place, it will affect the measurement accuracy.

[0005] In the process of implementing the present invention, the inventors found that there are at least the following problems in the prior art: The existing method of measuring the flatness of parts will result in measurement errors, which will affect the measurement accuracy, and the measurement efficiency and measurement quality are low. Summary of the invention

[0006] The purpose of the present invention is to provide a method and system for measuring the flatness of a part using multiple sensors, so as to solve the technical problems existing in the prior art that measurement errors may occur when measuring the flatness of a part, affecting the measurement accuracy, measurement efficiency and low measurement quality.

[0007] The various technical effects that can be produced by the preferred technical solutions among the various technical solutions provided by the present invention are described in detail below.

[0008] To achieve the above object, the present invention provides the following technical solutions: In a first aspect, the present invention provides a method for measuring the flatness of a part using multiple sensors, comprising: Using a sensor group to obtain N height measurement values ​​of a part at P specified positions, to obtain P groups of height data; wherein the sensor group is N sensors arranged in sequence in a first direction at a first pitch, and the specified positions are multiple positions of the part after it is displaced in sequence in the first direction at a second pitch; Reconstructing the height data of group P on the same coordinate system, and performing matching processing on the height data of group P to obtain a coincident flatness line; The coincident flatness lines are integrated to obtain the flatness of the part.

[0009] Optionally, a sensor group is used to obtain N height measurement values ​​of the part at P specified positions to obtain P groups of height data, including: Using the sensor group to obtain N height measurement values ​​of the part at an initial position, to obtain a first set of height data; Move the part in the first direction by the second distance based on the initial position, and use the sensor group to obtain N height measurement values ​​of the part at the second position to obtain a second set of height data; Move the part by the second distance in the first direction based on the second position, and use the sensor group to obtain N height measurement values ​​of the part when it is at a third position to obtain a third group of height data, until the sensor group is used to obtain the N most extreme height measurement values ​​of the part in the first direction to obtain a Pth group of height data.

[0010] Optionally, the initial position of the part is that the front end of the part in the first direction corresponds to the position of any sensor in the sensor group.

[0011] Optionally, reconstructing the P groups of height data on the same coordinate system and performing matching processing on the P groups of height data to obtain coincident planarity lines includes: Establish a coordinate system; Reconstructing N height measurement values ​​in the P group of height data on the coordinate system according to the direction coordinates and the height coordinates; The reconstructed P-th group of height data is matched with the reconstructed (P-1)-th group of height data to obtain an overlapping planarity line.

[0012] Optionally, matching the reconstructed P-th group of height data with the reconstructed (P-1)-th group of height data to obtain a coincident planarity line includes: Connecting N of the height measurement values ​​in each group of reconstructed height data to obtain P groups of height measurement lines; Confirming the height measurement value of the height measurement line of item P and the height measurement line of item (P-1) having the same direction coordinate; The P-th height measurement line is translated and rotated so that the P-th height measurement line coincides with the height measurement value having the same direction coordinates as the (P-1)-th height measurement line, thereby obtaining a coincident flatness line formed by the P-th height measurement lines.

[0013] Optionally, integrating the coincident flatness lines to obtain the flatness of the part includes: Extracting a plurality of flatness values ​​from the coincident flatness lines; The plurality of flatness values ​​are sequentially connected to obtain the flatness of the part.

[0014] Optionally, the distance of the second spacing is M times the first spacing, where 1≤M≤N-1, and M is an integer.

[0015] Optionally, the sensor in the sensor group is a capacitive sensor, a laser displacement sensor or a spectral confocal sensor.

[0016] In a second aspect, the present invention further provides a system for measuring the flatness of parts with multiple sensors, the system comprising a sensor group, a carrier platform and a processor, the processor being used to execute the method for measuring the flatness of parts with multiple sensors as described above; the sensor group is mounted on the top of the carrier platform and aligned with the carrier platform; the part is placed on the carrier platform and correspondingly arranged under the sensor group, and the part can be moved on the carrier platform; wherein the sensor group is N sensors arranged sequentially in a first direction at a first pitch, and the part is moved sequentially in the first direction of the carrier platform at a second pitch.

[0017] Optionally, the system further comprises a motion platform, which is disposed between the supporting platform and the part and is used to drive the part to move in a first direction of the supporting platform.

[0018] Implementing one of the above technical solutions of the present invention has the following advantages or beneficial effects: This embodiment requires the use of a sensor group to obtain N height measurement values ​​of the part at P specified positions; wherein the sensor group is N sensors arranged in sequence in the first direction according to a first spacing, and the specified positions are multiple positions after the part is displaced in sequence in the first direction according to a second spacing. In this way, the sensor group is used to obtain N height measurement values ​​of the part at P specified positions, and as much height data of the part at different positions as possible is obtained. By obtaining P groups of height data, reliable data support can be provided for subsequent numerical processing. In addition, the part will move according to a predetermined trajectory during the measurement process, and the sensor group is used to obtain the height data at the corresponding position. Even if the part will produce corresponding instability due to the unevenness of the support platform during the movement, this method of obtaining height data will not affect the numerical measurement of the sensor group, which can reduce measurement errors, improve measurement accuracy, and improve measurement efficiency.

[0019] Then, the P group height data is reconstructed on the same coordinate system, and the P group height data is matched to obtain the coincident flatness line. Finally, the coincident flatness lines are integrated to obtain the flatness of the part. Since the present embodiment uses a sensor group to obtain the height measurement value of the part at a specified position, it provides reliable data support for the subsequent matching process. After the data is processed, the flatness of the part can be restored to a greater extent, thereby improving the measurement quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. It is obvious that 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. In the drawings: Figure 1 It is a schematic flow chart of a method for measuring the flatness of a part using multiple sensors in the first embodiment of the present invention; Figure 2 is a flow chart of step S10 in the method for measuring the flatness of a part using multiple sensors in the first embodiment of the present invention; Figure 3a It is a structural schematic diagram of the height data of the part being acquired by the sensor group when the part is in the initial position in the first embodiment of the present invention; Figure 3b It is a structural schematic diagram of the height data of the part obtained by the sensor group when the part is in the second position in the first embodiment of the present invention; Figure 3c It is a structural schematic diagram of the height data acquired by the sensor group when the part is at the third position in the first embodiment of the present invention; Figure 41 is a flow chart of step S20 in the method for measuring the flatness of a part using multiple sensors in the first embodiment of the present invention; Figure 5 is a schematic diagram of reconstructing P groups of height data on a coordinate system to obtain P groups of height measurement lines in Embodiment 1 of the present invention; Figure 6 is a schematic diagram of obtaining the coincident planarity line in the first embodiment of the present invention; Figure 7 It is a schematic diagram of the structure of a system for measuring the flatness of parts with multiple sensors in the second embodiment of the present invention.

[0021] In the figure: 1. sensor group; 2. parts; 3. support platform; 4. motion platform. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solutions and advantages of the present invention clearer, the various exemplary embodiments to be described below will refer to the corresponding drawings, which constitute a part of the exemplary embodiments, wherein various exemplary embodiments that may be used to implement the present invention are described. Unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementation methods described in the following exemplary embodiments do not represent all implementation methods consistent with the present disclosure. It should be understood that they are only examples of processes, methods, devices, etc. that are consistent with some aspects of the present disclosure as detailed in the attached claims, and other embodiments may also be used, or the embodiments listed herein may be modified in structure and function without departing from the scope and essence of the present invention.

[0023] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", etc. indicate the orientation or positional relationship based on the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the elements referred to must have a specific orientation, be constructed and operated in a specific orientation. 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. The term "multiple" means two or more. The terms "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, an integral connection, a mechanical connection, an electrical connection, a communication connection, a direct connection, an indirect connection through an intermediate medium, and can be the internal connection of two elements or the interaction relationship between two elements. The term "and / or" includes any and all combinations of one or more related listed items. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0024] In order to illustrate the technical solution of the present invention, a specific embodiment is used below for description, and only the parts related to the embodiment of the present invention are shown.

[0025] Embodiment 1: like Figure 1 As shown, the present invention provides a method for measuring the flatness of a part using multiple sensors, comprising: S10, using a sensor group to obtain N height measurement values ​​of the part at P specified positions, to obtain P groups of height data; wherein the sensor group is N sensors arranged in sequence in a first direction according to a first spacing, and the specified positions are multiple positions after the part is displaced in sequence in the first direction according to a second spacing; S20, reconstructing the P groups of height data on the same coordinate system, and performing matching processing on the P groups of height data to obtain coincident flatness lines; S30, integrating the coincident flatness lines to obtain the flatness of the part.

[0026] In this embodiment, it is necessary to use a sensor group to obtain N height measurement values ​​of the part at P specified positions; wherein the sensor group is N sensors arranged in sequence in the first direction according to a first spacing, and the specified positions are multiple positions after the part is displaced in sequence in the first direction according to a second spacing. In this way, the sensor group is used to obtain N height measurement values ​​of the part at P specified positions, and as much height data of the part at different positions as possible is obtained. By obtaining N groups of height data, reliable data support can be provided for subsequent numerical processing. In addition, the part will move according to a predetermined trajectory during the measurement process, and the sensor group is used to obtain the height data at the corresponding position. Even if the part will produce corresponding instability due to the unevenness of the support platform during the movement, this method of obtaining height data will not affect the numerical measurement of the sensor group, which can reduce measurement errors, improve measurement accuracy, and improve measurement efficiency.

[0027] Then, the P group height data is reconstructed on the same coordinate system, and the P group height data is matched to obtain the coincident flatness line. Finally, the coincident flatness lines are integrated to obtain the flatness of the part. Since the present embodiment uses a sensor group to obtain the height measurement value of the part at a specified position, it provides reliable data support for the subsequent matching process. After the data is processed, the flatness of the part can be restored to a greater extent, thereby improving the measurement quality.

[0028] It should be noted that the parts measured in this embodiment are parts with shapes on the surface.

[0029] Next, combine Figure 1 The specific implementation steps of the method for measuring the flatness of parts with multiple sensors provided in this embodiment are described in detail: First, execute step S10, use the sensor group to obtain N height measurement values ​​of the part at P specified positions, and obtain P groups of height data; wherein the sensor group is N sensors arranged in sequence in the first direction according to a first spacing, and the specified positions are multiple positions after the part is displaced in sequence in the first direction according to a second spacing.

[0030] Specifically, the sensor is fixedly arranged, and N sensors are arranged in sequence in the first direction to form a sensor group. In addition, the part can be moved in the first direction, and the sensor group obtains the height data of the part at the specified position after the part moves to the specified position. It should be noted that since the sensor group includes N sensors, the sensor group will obtain N height measurement values ​​after the part moves to the specified position. At this time, the N height measurement values ​​measured by the sensor group are a set of height data.

[0031] The specific steps of executing step S10 are as follows: Figure 2 shown.

[0032] S11, using the sensor group to obtain N height measurement values ​​of the part at the initial position to obtain a first set of height data; S12, moving the part in the first direction by a second distance based on the initial position, and obtaining N height measurement values ​​of the part at the second position using the sensor group to obtain a second set of height data; S13, move the part in the first direction by a second distance based on the second position, use the sensor group to obtain N height measurement values ​​of the part when it is in the third position, and obtain a third group of height data, until the sensor group is used to obtain the N most extreme height measurement values ​​of the part in the first direction, and obtain the Pth group of height data.

[0033] In this embodiment, if Figure 3a , Figure 3b and Figure 3c As shown, the sensor group obtains multiple sets of height data when the part is at multiple specified positions.

[0034] First, the sensor group obtains N height measurement values ​​of the part at the initial position to obtain the first set of height data, such as Figure 3a As shown. The initial position of the part refers to the position where the front end of the part in the first direction corresponds to the position of any sensor in the sensor group. That is to say, when the part is in the initial position, the front end of the part in the first direction needs to correspond to the position of any sensor in the sensor group. This front end can be the front end of the part or the position of the part relatively forward in the first direction, which is not specifically limited in this embodiment. This makes it easier for the subsequent sensor group to obtain the height data of the part when it moves to the specified position in the first direction.

[0035] The first direction is from right to left. After the sensor group obtains the first set of height data of the part at the initial position, the part will move the second distance in the first direction based on the initial position, such as Figure 3b As shown, at this time, the part is in the second position, and at the same time, the sensor group obtains N height measurement values ​​of the part in the second position to obtain a second group of height data.

[0036] The part is then moved in the first direction by a second spacing based on the second position, such as Figure 3c As shown, at this time, the part is in the third position, and the sensor group will obtain N height measurement values ​​of the part in the third position to obtain a third set of height data.

[0037] Then, the part is moved in sequence according to the above method until the sensor group obtains the height measurement value of the end of the part in the first direction. That is, the rightmost end of the part is obtained by the rightmost sensor in the sensor group. At this point, the acquisition of all height data of the part is completed, providing a prerequisite for subsequent processing of the height data. Among them, P≥3 in the P group of height data.

[0038] Specifically, the sensor in the sensor group is a capacitive sensor, a laser displacement sensor, a spectral confocal sensor, or any other displacement sensor capable of measuring distance. In this embodiment, since the detection accuracy of the capacitive sensor is relatively high, usually reaching the micron level, the sensor is preferably a capacitive sensor.

[0039] It should be noted that, in this embodiment, the distance of the second spacing is M times the first spacing, where 1≤M≤N-1, and M is an integer. Assume that the sensor group includes five sensors, and the spacing between the sensors is 10mm, then the second spacing for the movement of the part can be 10mm, 20mm, 30mm or 40mm. Since the spacing between individual sensors is the first spacing, in order to facilitate the sensors in the sensor group to acquire the height data of the part and facilitate the subsequent reconstruction of the height data, the limitation of the second spacing can reduce the measurement error, ensure the stability of the acquired height data, and ensure the accuracy of the subsequent reconstruction of the height data.

[0040] Next, step S20 is executed to reconstruct the P groups of height data on the same coordinate system, and match the P groups of height data to obtain overlapping flatness lines. Specifically, the purpose of reconstructing multiple groups of height data is to numerically match the P groups of height data, and finally restore the overlapping flatness lines of the P groups of height data.

[0041] The specific operation steps of step S20 are as follows: Figure 4 shown.

[0042] S21, establishing a coordinate system; S22, reconstructing N height measurement values ​​in the P group of height data on a coordinate system according to direction coordinates and height coordinates; S23, matching the reconstructed P-th group of height data with the reconstructed (P-1)-th group of height data to obtain an overlapping planarity line.

[0043] Specifically, when reconstructing multiple sets of height data, a coordinate system needs to be established first. It should be noted that this coordinate system can be a plane coordinate system. Subsequently, when reconstructing N height measurement values ​​in P sets of height data in the coordinate system, each height measurement value will be converted into a coordinate point in the coordinate system. Each coordinate point has a corresponding direction coordinate and height coordinate. The direction coordinate is the horizontal coordinate in the coordinate system, and the height coordinate is the vertical coordinate in the coordinate system.

[0044] When executing step S22, the N height measurement values ​​in the P group of height data need to be reconstructed on the coordinate system to ensure the integrity of the data and facilitate subsequent data matching processing. However, it should be noted that at this time, there are only coordinate points composed of P×N height measurement values ​​on the coordinate system.

[0045] like Figure 5 As shown, after P groups of height data are reconstructed on the coordinate system, step S23 is then executed to match the reconstructed Pth group of height data with the reconstructed (P-1)th group of height data to obtain overlapping planarity lines.

[0046] The specific steps of step S23 include: Connecting N height measurement values ​​in each group of reconstructed height data to obtain P groups of height measurement lines; Confirm the height measurement value of the Pth height measurement line and the (P-1)th height measurement line with the same direction coordinate; The Pth height measurement line is translated and rotated so that the height measurement value of the Pth height measurement line and the (P-1)th height measurement line with the same direction coordinate coincide with each other, thereby obtaining a coincident flatness line formed by the P height measurement lines.

[0047] First, if Figure 5As shown, it is necessary to first connect the coordinate points corresponding to the N height measurement values ​​in each group of reconstructed height data, and obtain the P group of height measurement lines according to the coordinate points of the P group of height data in the coordinate system. Subsequently, confirm the height measurement values ​​with the same directional coordinates in the P-th height measurement line and the (P-1)-th height measurement line, and compare the P-th group of height measurement lines with the (P-1) group of height measurement lines, that is, select a group (hereinafter referred to as this group) of height measurement lines to compare with the previous group of height measurement lines. The height measurement lines of this group and the height measurement lines of the previous group are composed of connecting the N height measurement values ​​in the height data, and the position when obtaining the height data of this group is changed based on the position when the height data of the previous group is obtained. Therefore, the directional coordinates of the N height measurement values ​​in this group of height measurement lines will coincide with the directional coordinates of several height measurement values ​​in the previous group. The coincidence of directional coordinates means that the height measurement values ​​of the same point on the surface of the part at different specified positions of the part are obtained by different sensors, but their height measurement values ​​are the same.

[0048] Then, the height measurement lines of this group are translated and rotated so that the height measurement values ​​of this group of height measurement lines coincide with the height measurement values ​​of the previous group of height measurement lines with the same direction coordinates, and a coincident flatness line formed by multiple height measurement lines is obtained. Specifically, since multiple height measurement lines have been reconstructed on the plane coordinate system, and each group of height measurement lines has a part of the direction coordinates that coincides with the previous group of height measurement lines, it is necessary to match the parts of the direction coordinates that coincide to obtain a coincident flatness line.

[0049] Specifically, the Pth height measurement line is translated and rotated so that the height measurement value with the same directional coordinate in the Pth height measurement line coincides with the height measurement value with the same directional coordinate in the (P-1)th height measurement line, including: translating the Pth height measurement line so that a height measurement value in the Pth height measurement line coincides with one of the height measurement values ​​with the same directional coordinate in the (P-1)th height measurement line, after the coincidence, confirming the angle difference between the Pth height measurement line and the (P-1)th height measurement line, and rotating the Pth height measurement line until the Pth height measurement line completely coincides with the height measurement value with the same directional coordinate in the (P-1)th height measurement line.

[0050] For example, the height measurement lines of this group and the previous group of height measurement lines are both composed of 5 height measurement values, and the height measurement values ​​are converted into five coordinate points for reconstruction in the plane coordinate system. The direction coordinates of the three height measurement values ​​at the left end of the height measurement lines of this group are the same as the direction coordinates of the three height measurement values ​​at the right end of the height measurement lines of the previous group, which means that the direction coordinates of the three height measurement values ​​in the height measurement lines of this group coincide with the direction coordinates of the three height measurement values ​​in the height measurement lines of the previous group. At this time, the height measurement lines of this group are displaced up and down so that the three height measurement values ​​in the height measurement lines of this group coincide with the three height measurement values ​​in the height measurement lines of the previous group. If there is no coincidence after the up and down displacement, the first height measurement value at the left end of this group is coincided with the third height measurement value at the right end of the previous group, and then the angle difference between this height measurement line and the previous group of height measurement lines is confirmed. After confirmation, the height measurement line is rotated until the coordinates of the three height measurement values ​​at the left end of this group completely coincide with the coordinates of the three height measurement values ​​at the right end of the height measurement lines of the previous group. By doing the same process as above for each height measurement line in turn, we can obtain the coincident flatness line formed by multiple height measurement lines, such as Figure 6 shown.

[0051] The coincident flatness line is the flatness line of the part after reconstruction and matching processing on the plane coordinate system. After executing step 20, the flatness line of the part on the coordinate system is obtained. After reconstructing the flatness of the part, the basic shape of the part flatness is determined. In addition, during the reconstruction of the height data of group P, the uneven data generated by the carrier platform will be eliminated. Even if the part will produce corresponding instability due to the unevenness of the carrier platform during movement, this method of obtaining height data will not affect the numerical measurement of the sensor group, which can reduce measurement errors, improve measurement accuracy, and improve measurement efficiency.

[0052] Finally, execute step S30 to integrate the coincident flatness lines to obtain the flatness of the part. The basic steps to obtain the flatness of the part include: extracting multiple flatness values ​​from the coincident flatness lines; connecting the multiple flatness values ​​in sequence to obtain the flatness of the part. Specifically, the coincident flatness lines in the coordinate system are extracted, and multiple flatness values ​​in the coincident flatness lines, that is, flatness coordinates, are obtained. The multiple flatness values ​​are extracted, and the multiple flatness values ​​are connected in sequence to obtain the flatness of the part. At this point, the flatness of the part has been completely restored.

[0053] The part flatness finally extracted through the above steps can be highly consistent with the flatness of the actual part, providing a more accurate flatness measurement solution for the part. Even if the part will produce corresponding instability due to the unevenness of the carrier during movement, it will not affect the measurement value of the sensor group, thereby reducing measurement errors, improving measurement accuracy, and improving measurement efficiency.

[0054] In this embodiment, one sensor group is used to acquire the height data of the part, and the plane coordinate system is used to reconstruct the height data later, but this is only the corresponding technical solution recorded in this embodiment for the convenience of explaining the principle. In other embodiments, if the part is large, multiple sensor groups can be used to acquire the height data of the part, and a multi-dimensional coordinate system can be used to reconstruct the data later, which will not be described in detail in this embodiment.

[0055] The embodiment is only a specific example and does not represent only one implementation mode of the present invention.

[0056] Embodiment 2: Based on the same inventive concept, the present invention also provides a system for measuring the flatness of parts with multiple sensors, such as Figure 7 As shown, the system includes a sensor group 1, a carrier platform 3 and a processor, and the processor is used to execute the method of measuring the flatness of a part using multiple sensors as described in the embodiment; the sensor group 1 is mounted on the top of the carrier platform 3 and is aligned with the carrier platform 3; the part 2 is placed on the carrier platform 3 and is correspondingly arranged below the sensor group 1, and the part 2 can move on the carrier platform 3; wherein the sensor group 1 is N sensors arranged sequentially in a first direction at a first spacing, and the part 2 moves sequentially in the first direction of the carrier platform 3 at a second spacing.

[0057] It should be noted that the distance of the second spacing is M times the first spacing, where 1≤M≤N-1, and M is an integer. Since the spacing between individual sensors is the first spacing, in order to facilitate the sensors in the sensor group 1 to obtain the height data of the part 2, the second spacing is limited, which can reduce the measurement error and ensure the accuracy and stability of the obtained height data.

[0058] Specifically, the sensor group 1 is N sensors arranged in sequence in the first direction according to the first spacing, and the sensor group 1 is mounted on the top of the carrier 3 and aligned with the carrier 3. The part 2 is placed on the carrier 3 and aligned with the sensor group 1 below, and the part 2 can be moved in sequence in the first direction of the carrier 3 according to the second spacing, and the sensor group 1 mounted above the carrier 3 obtains the height measurement value of the part 2 at the specified position. In this embodiment, the height measurement value of the part 2 is obtained by using N sensors to ensure the reliability of the height measurement value. Even if the part 2 produces corresponding instability due to the unevenness of the carrier 3 during the movement, it will not affect the measurement value of the sensor group 1, thereby reducing the measurement error, improving the measurement accuracy, and improving the measurement efficiency and measurement quality.

[0059] The specific method for obtaining the height data of the part 2 has been described in the first embodiment and will not be described in detail here.

[0060] As an optional implementation, the system further includes a motion platform 4, which is disposed between the carrier 3 and the part 2, and is used to drive the part 2 to move in the first direction of the carrier 3. Specifically, the system described in the second embodiment may further include a motion platform 4, which may be a motion trolley, and drives the part 2 to move in the first direction of the carrier 3 according to the second spacing, thereby improving the accuracy of the position movement of the part 2 and improving the accuracy of obtaining the height measurement value of the part 2.

[0061] The above description is only the preferred embodiment of the present invention. It is known to those skilled in the art that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, under the teachings of the present invention, these features and embodiments may be modified to adapt to specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application belong to the protection scope of the present invention.

Claims

1. A method for measuring the flatness of a part using multiple sensors, characterized in that: include: Using a sensor group to obtain N height measurement values ​​of a part at P specified positions, to obtain P groups of height data; wherein the sensor group is N sensors arranged in sequence in a first direction at a first pitch, and the specified positions are multiple positions of the part after it is displaced in sequence in the first direction at a second pitch; Reconstructing the height data of group P on the same coordinate system, and performing matching processing on the height data of group P to obtain a coincident flatness line; The coincident flatness lines are integrated to obtain the flatness of the part.

2. The method for measuring the flatness of a part using multiple sensors according to claim 1, characterized in that: Use the sensor group to obtain N height measurement values ​​of the part at P specified positions to obtain P groups of height data, including: Using the sensor group to obtain N height measurement values ​​of the part at an initial position, to obtain a first set of height data; Move the part in the first direction by the second distance based on the initial position, and use the sensor group to obtain N height measurement values ​​of the part at the second position to obtain a second set of height data; Move the part by the second distance in the first direction based on the second position, and use the sensor group to obtain N height measurement values ​​of the part when it is at a third position to obtain a third group of height data, until the sensor group is used to obtain the N most extreme height measurement values ​​of the part in the first direction to obtain a Pth group of height data.

3. The method for measuring the flatness of a part using multiple sensors according to claim 2, characterized in that: The initial position of the part is that the front end of the part in the first direction corresponds to the position of any sensor in the sensor group.

4. The method for measuring the flatness of a part using multiple sensors according to claim 1, characterized in that: The step of reconstructing the height data of the P groups on the same coordinate system and performing matching processing on the height data of the P groups to obtain coincident planarity lines includes: Establish a coordinate system; Reconstructing N height measurement values ​​in the P group of height data on the coordinate system according to the direction coordinates and the height coordinates; The reconstructed P-th group of height data is matched with the reconstructed (P-1)-th group of height data to obtain an overlapping planarity line.

5. The method for measuring the flatness of a part using multiple sensors according to claim 4, characterized in that: The matching process of reconstructing the Pth group of height data with the (P-1)th group of height data to obtain a coincident planarity line includes: Connecting N of the height measurement values ​​in each group of reconstructed height data to obtain P groups of height measurement lines; Confirming the height measurement value of the height measurement line of item P and the height measurement line of item (P-1) having the same direction coordinate; The P-th height measurement line is translated and rotated so that the P-th height measurement line coincides with the height measurement value having the same direction coordinates as the (P-1)-th height measurement line, thereby obtaining a coincident flatness line formed by the P-th height measurement lines.

6. The method for measuring the flatness of a part using multiple sensors according to claim 1, characterized in that: The step of integrating the coincident flatness lines to obtain the flatness of the part comprises: Extracting a plurality of flatness values ​​from the coincident flatness lines; The plurality of flatness values ​​are sequentially connected to obtain the flatness of the part.

7. The method for measuring the flatness of a part using multiple sensors according to claim 1, characterized in that: The distance of the second spacing is M times the first spacing, where 1≤M≤N-1, and M is an integer.

8. The method for measuring the flatness of a part using multiple sensors according to claim 1, characterized in that: The sensor in the sensor group is one of a capacitive sensor, a laser displacement sensor or a spectral confocal sensor.

9. A system for measuring the flatness of parts using multiple sensors, characterized in that: The system includes a sensor group, a support platform and a processor, the processor is used to execute the method of measuring the flatness of a part using multiple sensors as described in any one of claims 1 to 8; the sensor group is mounted on the top of the support platform and is aligned with the support platform; the part is placed on the support platform and is correspondingly arranged under the sensor group, and the part can be moved on the support platform; wherein the sensor group is N sensors arranged in sequence in a first direction at a first spacing, and the part is moved in sequence in the first direction of the support platform at a second spacing.

10. The multi-sensor part flatness measurement system according to claim 9, characterized in that: The system further comprises a motion platform, which is arranged between the support platform and the part and is used for driving the part to move in a first direction of the support platform.

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