Device calibration method and system, electronic device, and storage medium

Abstract

The application provides a device calibration method, system, electronic device and storage medium. The device calibration method comprises: obtaining a first coordinate set obtained by a laser tracker measuring a calibration board in different positions; obtaining a second coordinate set obtained by an optical tracking system measuring the calibration board in different positions, and obtaining a target point coordinate set obtained by the laser tracker measuring a target point of the optical tracking system; determining a first target conversion relationship between a first coordinate system of the laser tracker and a second coordinate system of the optical tracking system based on the first coordinate set and the second coordinate set; determining a second target conversion relationship between the second coordinate system and the target point based on the first target conversion relationship and the target point coordinate set; and completing calibration of the laser tracker and the optical tracking system based on the second target conversion relationship. The above method can improve the accuracy of device calibration.

Description

Technical Field

[0001] This application relates to the field of scanning, and more particularly to a device calibration method, system, electronic device, and storage medium. Background Technology

[0002] When scanning an object using a 3D scanning system, a tracker is needed to position the scanner in real time to obtain the scanned object's data. Due to the limited measurement range of the tracker, markers need to be placed on the object or in a common area, and the tracker's position needs to be moved to complete the transformation between different coordinate systems. When the object being scanned is large, the tracker's position needs to be moved multiple times to collect the scanned data. Therefore, using markers for station calibration can lead to the accumulation of multiple station errors during subsequent scanning, affecting the scanning accuracy. Summary of the Invention

[0003] This application discloses a device calibration method, system, electronic device, and storage medium, which solves the technical problem of large cumulative errors during station transfer.

[0004] This application provides a device calibration method, the method comprising: acquiring a first coordinate set obtained by a laser tracker measuring a calibration plate at different positions; acquiring a second coordinate set obtained by an optical tracking system measuring the calibration plate at different positions; and acquiring a target point coordinate set obtained by the laser tracker measuring a target point of the optical tracking system; determining a first target transformation relationship between a first coordinate system of the laser tracker and a second coordinate system of the optical tracking system based on the first coordinate set and the second coordinate set; determining a second target transformation relationship between the second coordinate system and the target point based on the first target transformation relationship and the target point coordinate set; and completing the calibration of the optical tracking system based on the second target transformation relationship.

[0005] In some embodiments of this application, the optical tracking system includes a scanner, and the acquisition of a first coordinate set obtained by the laser tracker measuring the calibration plate at different positions includes: acquiring the scanner scanning the calibration plate at different positions to obtain a scan coordinate set; and based on the transformation relationship between the coordinate system of the scanner and the second coordinate system, transforming the scan coordinate set to the second coordinate system to obtain the second coordinate set.

[0006] In some embodiments of this application, determining the first target transformation relationship between the first coordinate system of the laser tracker and the second coordinate system of the optical tracking system based on the first coordinate set and the second coordinate set includes: obtaining a first adjacent coordinate pair from the first coordinate set, wherein the first adjacent coordinate pair is determined based on any two adjacent positions of the calibration plate during movement; obtaining a second adjacent coordinate pair from the second coordinate set, wherein the second adjacent coordinate pair is determined based on the arbitrary two adjacent positions; determining a first transformation relationship for each of the plurality of first adjacent coordinate pairs; determining a second transformation relationship for each of the plurality of second adjacent coordinate pairs; and determining the first target transformation relationship based on the first transformation relationship of each of the first adjacent coordinate pairs and the second transformation relationship of each of the second adjacent coordinate pairs.

[0007] In some embodiments of this application, after calibrating the optical tracking system, the method further includes: determining a first position and a second position of the optical tracking system during movement; acquiring the first coordinates of the target point obtained by the laser tracker measuring the target point when the optical tracking system is in the first position, and the second coordinates of the target point obtained by the optical tracking system measuring the target point when it is in the second position; and determining the position transformation relationship between the second coordinate system of the optical tracking system in the first position and the second coordinate system of the optical tracking system in the second position based on the first coordinates of the target point, the second coordinates of the target point, and the transformation relationship between the second target and the first coordinates of the target point.

[0008] In some embodiments of this application, the method further includes: acquiring first data of the scanner scanning the object under test when the optical tracking system is in the first position; acquiring second data of the scanner scanning the object under test when the optical tracking system is in the second position; and converting the first data and the second data to a first reference coordinate system based on the position transformation relationship, wherein the first reference coordinate system is determined from the second coordinate system of the optical tracking system at different positions, and each position of the optical tracking system has a corresponding second coordinate system.

[0009] In some embodiments of this application, obtaining the first coordinate set obtained by the laser tracker measuring the calibration plate at different positions includes: obtaining the first sub-coordinate set obtained by each of the multiple laser trackers measuring the calibration plate at different positions, wherein the different positions are within the common field of view of the multiple laser trackers and the optical tracking system; determining the first relative positional relationship between the corresponding first coordinate systems of the multiple laser trackers based on the first sub-coordinate set corresponding to each laser tracker; transforming the first sub-coordinate set corresponding to each laser tracker to a second reference coordinate system based on the first relative positional relationship to determine the first coordinate set; wherein the second reference coordinate system is determined from the corresponding first coordinate systems of the multiple laser trackers; correspondingly, determining the first target transformation relationship between the first coordinate system of the laser tracker and the second coordinate system of the optical tracking system based on the first coordinate set and the second coordinate set includes: determining the first target transformation relationship between the second reference coordinate system and the second coordinate system based on the first coordinate set and the second coordinate set.

[0010] In some embodiments of this application, obtaining the second coordinate set obtained by the optical tracking system measuring the calibration plate at different positions includes: obtaining the second sub-coordinate set obtained by each of the multiple optical tracking systems measuring the calibration plate at different positions, wherein the different positions are located within the common field of view of the multiple trackers and the laser tracker; determining a second relative positional relationship between the corresponding second coordinate systems of each optical tracking system based on the second sub-coordinate set corresponding to each optical tracking system; transforming the second sub-coordinate set corresponding to each optical tracking system to a third reference coordinate system based on the second relative positional relationship, and determining the second coordinate set; wherein the third reference coordinate system is determined from the second coordinate system corresponding to each optical tracking system; correspondingly, determining the first target transformation relationship between the first coordinate system of the laser tracker and the second coordinate system of the optical tracking system based on the first coordinate set and the second coordinate set includes: determining the first target transformation relationship between the third reference coordinate system and the first coordinate system based on the first coordinate set and the second coordinate set.

[0011] This application also provides a device calibration system, comprising: a laser tracker for measuring a calibration plate at different positions to obtain a first coordinate set; an optical tracking system for measuring the calibration plate at different positions to obtain a second coordinate set, and for acquiring a target point coordinate set obtained by the laser tracker measuring a target point of the optical tracking system; an electronic device for determining a first target transformation relationship between a first coordinate system of the laser tracker and a second coordinate system of the optical tracking system based on the first coordinate set and the second coordinate set; the electronic device is further configured to determine a second target transformation relationship between the second coordinate system and the target point based on the first target transformation relationship and the target point coordinate set; and the electronic device is further configured to complete the calibration of the optical tracking system based on the second target transformation relationship.

[0012] This application also provides an electronic device, which includes a processor and a memory, wherein the processor is used to implement the device calibration method when executing a computer program stored in the memory.

[0013] This application also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the device calibration method described above.

[0014] In the device calibration method provided in this application, a first coordinate set is obtained by the laser tracker measuring the calibration plate at different positions, and a second coordinate set is obtained by the optical tracking system measuring the calibration plate at different positions. This dynamically changing calibration plate provides a common reference benchmark for both the laser tracker and the optical tracking system in physical space, and also provides multi-source calibration data and reduces the accumulation of single-point errors. Furthermore, a target point coordinate set is obtained by the laser tracker measuring the target point of the optical tracking system. After determining the first and second coordinate sets, a first target transformation relationship between the first coordinate system of the laser tracker and the second coordinate system of the optical tracking system is determined based on the first and second coordinate sets. Then, using the first target transformation relationship and the calibration point coordinate set, a second target transformation relationship between the second coordinate system and the target point is determined, completing the calibration of the optical tracking system. Through the above embodiments, a unified coordinate system can be achieved, and large accumulated errors during station transitions can be avoided, thus improving scanning accuracy to a certain extent. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the architecture of the device calibration system provided in the embodiments of this application.

[0016] Figure 2 This is a flowchart of the device calibration method provided in the embodiments of this application.

[0017] Figure 3 This is a schematic diagram of an application scenario provided in the embodiments of this application.

[0018] Figure 4 This is an application flowchart of the second target transformation relationship provided in the embodiments of this application.

[0019] Figure 5 This is a flowchart illustrating the process of obtaining the first coordinate set provided in an embodiment of this application.

[0020] Figure 6 This is a measurement schematic diagram of multiple laser trackers provided in the embodiments of this application.

[0021] Figure 7 This is a flowchart illustrating the process of obtaining the first coordinate set provided in an embodiment of this application.

[0022] Figure 8 This is a measurement schematic diagram of multiple optical tracking systems provided in the embodiments of this application.

[0023] Figure 9 This is a schematic diagram of the structure of the electronic device provided in the embodiments of this application. Detailed Implementation

[0024] For ease of understanding, some concepts related to the embodiments of this application are illustrated and explained by way of example for reference.

[0025] It should be noted that in this application, "at least one" means one or more, and "more than one" means two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone, where A and B can be singular or plural. The terms "first," "second," "third," "fourth," etc. (if present) in the specification, claims, and drawings of this application are used to distinguish similar objects, not to describe a specific order or sequence.

[0026] In the automotive, shipbuilding, and aerospace industries, 3D scanning systems are commonly used to acquire 3D data. A 3D scanning system includes a tracker and a scanner (such as a handheld scanner), and the tracker can include laser trackers and optical tracking systems. An optical tracking system can position a handheld scanner in real time to scan objects without markers (such as large workpieces), thereby acquiring the corresponding 3D data. The measurement range of an optical tracking system is limited, typically between 3m and 10m. When the object being scanned is large enough to exceed the measurement range of the optical tracking system, it is necessary to move the system to complete the 3D data acquisition.

[0027] Before actual scanning, a transformation between different coordinate systems is required for station calibration. Related technologies involve attaching markers to objects or public areas and then moving the optical tracking system to complete the coordinate system transformation. However, this method cannot guarantee scanning accuracy for large scenes, and when multiple station changes are needed, the accumulated errors from these changes can affect the accuracy of subsequent optical tracking system scans.

[0028] To address the technical problem of significant cumulative errors during station transitions, this application provides a device calibration method, system, electronic device, and storage medium. A laser tracker assists the optical tracking system in completing station transition calibration, unifying the first coordinate system of the laser tracker and the second coordinate system of the optical tracking system, thus ensuring scanning accuracy for large workpieces. Furthermore, by performing station transition calibration through dynamic position changes, the accuracy of station transition calibration can be improved. In subsequent scanning processes, the cumulative errors that occur after multiple station transitions can be avoided, thereby improving subsequent scanning accuracy to a certain extent. The architecture of the device calibration system of this application is described below.

[0029] Figure 1 This is a schematic diagram of the architecture of the device calibration system provided in an embodiment of this application. For example... Figure 1 As shown, the equipment calibration system includes an electronic device 10, a laser tracker 20, and an optical tracking system 30. However, this embodiment does not limit the number of laser trackers 20 and optical tracking systems 30.

[0030] Electronic device 10 may include devices with communication functions such as laptops, tablets, programmable logic controllers (PLCs), and human-machine interfaces (HMIs) with touch input capabilities, or devices simulated by virtual machines or simulators. Electronic device 10 is used to receive data sent by laser tracker 20 and optical tracking system 30, and to perform calculations on the data to complete the device's relocation calibration.

[0031] The laser tracker 20 is a high-precision, large-size measuring instrument capable of accurate point measurement in large scenes, used to measure the coordinates of marker points on a calibration board. These marker points, also known as reflective markers, can be objects of various shapes and materials. The laser tracker 20 transmits the coordinates of the marker points on the calibration board to the electronic device 10.

[0032] The optical tracking system 30 can directly measure the coordinates of the marker points on the calibration board using the optical tracker 310. The optical tracking system 30 can transmit the coordinates of the measured marker points on the calibration board to the electronic device 10. In addition, the optical tracking system 30 can be equipped with target points. After the equipment calibration is completed, the laser tracker 20 can also measure the coordinates of the target points and send the measured coordinates of the target points to the electronic device 10.

[0033] The optical tracking system 30 can also measure the coordinates of the marker points on the calibration plate via the scanner 320. The optical tracker 310 and the scanner 320 in the optical tracking system 30 can be two independently operating devices that can communicate with each other, or they can be two sub-devices belonging to the same system (e.g., a tracking scanner). They can be assembled and operated collaboratively, or they can be disassembled and operated independently. This application does not limit the device form or operation mode of the optical tracker 310 and the scanner 320.

[0034] In the application scenario of the equipment calibration system, in one example, a laser tracker 20 and an optical tracking system 30 can be fixed at a preset position. In another example, multiple optical tracking systems 30 and / or multiple laser trackers 20 can be fixed at a preset position. Taking the fixing of a laser tracker 20 and an optical tracking system 30 at a preset position as an example, a dynamically movable calibration plate can be placed between the laser tracker 20 and the optical tracking system 30. The laser tracker 20 can measure the coordinate set corresponding to the calibration plate at different positions. The optical tracking system 30 can measure the coordinate set corresponding to the calibration plate at different positions through the optical tracker 310, and can also obtain the coordinate set through the scanner 320. The electronic device 10 can receive the coordinate sets measured by the laser tracker 20 and the optical tracking system 30, thereby realizing the calibration of the optical tracking system 30.

[0035] The illustration Figure 1 This is merely an example of an equipment calibration system and does not constitute a limitation on the equipment calibration system. It may include more or fewer components than shown, or combine certain components, or different components. For example, the equipment calibration system may also include a camera device, etc.

[0036] Figure 2 This is a flowchart of a device calibration method provided in an embodiment of this application, applied to electronic devices (e.g., Figure 1 In electronic device 10). Depending on different needs, the order of steps in this flowchart can be changed, and some steps can be omitted.

[0037] Step S201: Obtain the first coordinate set obtained by the laser tracker measuring the calibration plate at different positions.

[0038] In some embodiments of this application, the laser tracker can be pre-fixed in a position, meaning that the position of the laser tracker relative to the ground does not change during the equipment calibration process. A calibration plate is placed within the measurement range of the laser tracker. A target mount can be provided on the calibration plate, and marker points can be placed on the target mount. These marker points can be high-precision reflective markers, such as Hubbs markers.

[0039] In some embodiments of this application, the calibration plate can be moved manually by the user, or it can be moved with the assistance of other self-moving devices; this application does not limit this. The calibration plate is moved according to a preset step size, and the multiple positions reached by the calibration plate are recorded. In one example, assuming the step size is 5m, the calibration plate is moved to position A by a length of 5m. After moving another 5m from the 5m position to position B, position A is 5m from the starting point, and position B is 10m from the starting point. The above are just examples; the step size can be set according to actual needs, and there can be multiple different step sizes; this application does not limit this. Furthermore, the number of times the calibration plate is moved is not limited; there can be more moves than in the above example. In another example, multiple calibration plates can be set within the measurement range of the laser tracker; this application does not limit the number of calibration plates.

[0040] A laser tracker can detect calibration points on a calibration board at different locations, thereby obtaining the coordinates of each measured calibration point in the laser tracker's coordinate system (such as the first coordinate system). The set of coordinates corresponding to multiple locations obtained by the laser tracker is denoted as the first coordinate set. Continuing the example above, the electronic device obtains the coordinates P11 of the marker point in the first coordinate system when the calibration board is at position A, and obtains the coordinates P12 of the marker point in the first coordinate system when the calibration board is at position B. The electronic device records coordinates P11 and P12 as two coordinates in the first coordinate set. This is just an example; if the calibration board is at multiple locations, the coordinates corresponding to each location are recorded as the first coordinate set.

[0041] Step S202: Obtain the second coordinate set obtained by the optical tracking system measuring the calibration plate at different positions, and the target point coordinate set obtained by the laser tracker measuring the target point of the optical tracking system.

[0042] In some embodiments of this application, the optical tracking system can be pre-fixed at a position, meaning its position relative to the ground remains unchanged during device calibration. The position of the optical tracking system differs from that of the laser tracker. The measurement ranges of the optical tracking system and the laser tracker at least partially overlap, and the calibration plate moves within this overlap range, meaning that the optical tracking system and the laser tracker can simultaneously detect the same calibration plate.

[0043] An optical tracking system can detect marker points on a calibration board at different positions, thereby obtaining the coordinates of the calibration point measured at each position in the coordinate system's coordinate system (such as a second coordinate system). The set of coordinates corresponding to multiple positions obtained by the optical tracking system is denoted as the second coordinate set. Continuing the example above, the electronic device obtains the coordinates P21 of the marker point in the second coordinate system when the calibration board is at position A, and obtains the coordinates P22 of the marker point in the second coordinate system when the calibration board is at position B. The electronic device records coordinates P21 and P22 as two coordinates in the second coordinate set. This is just an example; if the calibration board is at multiple positions, the coordinates corresponding to each position are recorded as part of the second coordinate set.

[0044] In other embodiments of this application, the optical tracking system may include a scanner, which can scan a calibration plate at different positions to obtain a set of scan coordinates. Based on the transformation relationship between the scanner's coordinate system and the optical tracking system's coordinate system (such as a second coordinate system), the scan coordinate set is transformed to the second coordinate system, thereby obtaining a second coordinate set in the second coordinate system.

[0045] In some embodiments of this application, a target mount is provided on the optical tracking system, and the relative position of the target mount and the optical tracking system remains unchanged. Multiple target points are deployed on the target mount. The laser tracker can detect multiple target points to obtain a set of target point coordinates.

[0046] To better understand the acquisition process of steps S201 and S202, combined with Figure 3 Describe it. For example... Figure 3 As shown, a calibration plate with calibration points is placed within the common field of view of the laser tracker 20 and the optical tracking system 30. Based on a preset moving direction and moving step size (which can also be a random step size), the calibration plate is moved sequentially through positions A, B, C, ..., N. Since the positions of the laser tracker 20 and the optical tracking system 30 remain unchanged, the laser tracker 20 can record the target points on the optical tracking system 30 at any time. Figure 3 (Coordinates not shown). When the calibration plate is at position A, the laser tracker 20 and the optical tracking system 30 simultaneously record the coordinates of position A in the coordinate system of the laser tracker 20 and the second coordinate system of the optical tracking system 30. When the calibration plate is at position B, the laser tracker 20 and the optical tracking system 30 simultaneously record the coordinates of position B in the coordinate system of the laser tracker 20 and the second coordinate system of the optical tracking system 30. This process continues until N coordinates of positions in the coordinate system of the laser tracker 20 and the second coordinate system of the optical tracking system 30 are recorded.

[0047] In addition, such as Figure 3As shown, the optical tracking system 30 can also record the coordinates of the corresponding position in the coordinate system of the scanner 320, and then, based on the transformation relationship between the coordinate system of the optical tracking system 30 and the coordinate system of the scanner 320, transform the coordinates recorded by the scanner 320 into the coordinate system of the optical tracking system 30.

[0048] Step S203: Based on the first coordinate set and the second coordinate set, determine the first target transformation relationship between the first coordinate system of the laser tracker and the second coordinate system of the optical tracking system.

[0049] In some embodiments of this application, in order to determine the transformation relationship between the first coordinate system of the laser tracker and the second coordinate system of the optical tracking system, a plurality of consecutive first adjacent coordinate pairs are obtained from the first coordinate set, and a plurality of consecutive second adjacent coordinate pairs are obtained from the second coordinate set.

[0050] The first adjacent coordinate pair is determined based on any two adjacent positions of the calibration plate during its movement. In one example, if the calibration plate is determined to have consecutive positions A, B, and C during its movement, then positions A and B are adjacent, and positions B and C are adjacent. The coordinates P11 corresponding to position A, P12 corresponding to position B, and P13 corresponding to position C are obtained from the first coordinate set. The coordinates P11 corresponding to position A and P12 corresponding to position B constitute the first first adjacent coordinate pair. The coordinates P12 corresponding to position B and P13 corresponding to position C constitute the second first adjacent coordinate pair. The first and second first adjacent coordinate pairs include the same coordinate P12.

[0051] Similarly, the second adjacent coordinate pair is also determined based on the aforementioned consecutive positions A, B, and C. That is, the two adjacent positions that determine the first adjacent coordinate are the same as the two positions that determine the second adjacent coordinate, ensuring that the first and second adjacent coordinate pairs are determined based on the same two adjacent positions. In one example, the coordinates P21 corresponding to position A, P22 corresponding to position B, and P23 corresponding to position C are obtained from the second coordinate set. Since positions A and B are adjacent, coordinates P21 and P22 are taken as the first second adjacent coordinate pair. Since positions B and C are adjacent, coordinates P22 and P23 are taken as the second second adjacent coordinate pair.

[0052] In some embodiments of this application, after determining multiple first adjacent coordinate pairs, a first transformation relationship is determined for each first adjacent coordinate pair. The first transformation relationship represents the transformation relationship between coordinates when transforming from adjacent first positions to second positions in the first coordinate system of the laser tracker. Continuing with the above example, the first transformation relationship S11 is calculated based on the first first adjacent coordinate pair, and the first transformation relationship S12 is calculated based on the second first adjacent coordinate pair.

[0053] After determining multiple second adjacent coordinate pairs, a second transformation relationship is determined for each second adjacent coordinate pair. Continuing with the example above, the second transformation relationship S21 is calculated based on the first second adjacent coordinate pair, and the second transformation relationship S22 is calculated based on the second second adjacent coordinate pair.

[0054] The first target transformation relationship is calculated based on the first transformation relationship of each first adjacent coordinate pair and the second transformation relationship of each second adjacent coordinate pair. Continuing the example above, the first target transformation matrix is ​​calculated based on the hand-eye calibration relationship, and the first target transformation relationship is determined based on the first target transformation matrix, for example, S11X=S21X, S12X=S22X. Here, X represents the first target transformation matrix, used to determine the first target transformation relationship.

[0055] Step S204: Based on the first target transformation relationship and the target point coordinate set, determine the second target transformation relationship between the second coordinate system and the target points.

[0056] In some embodiments of this application, the first target transformation relationship represents the transformation relationship between the first coordinate system of the laser tracker and the second coordinate system of the optical tracking system. The target point coordinate set belongs to the measured values ​​corresponding to the target points on the optical tracking system. Therefore, based on the first target transformation relationship and the target point coordinate set, the second target transformation relationship between the second coordinate system and the target points can be calculated, thereby determining the second target transformation relationship based on the second target transformation matrix. In one example, the second target transformation relationship = the inverse matrix of the first target transformation matrix corresponding to the first target transformation relationship × the target point coordinate set.

[0057] Step S205: Based on the second target conversion relationship, complete the calibration of the optical tracking system.

[0058] In some embodiments of this application, the second target transformation relationship represents the local coordinates of the target point in the second coordinate system of the optical tracking system, characterizing the position of the target point in the second coordinate system. In subsequent practical applications, the location of the optical tracking system and the transformation relationship between the second coordinate systems corresponding to optical tracking systems at different locations can be determined through the second target transformation relationship, thereby achieving coordinate system unification.

[0059] Through the above embodiments, a first coordinate set is obtained by the laser tracker measuring the calibration plate at different positions, and a second coordinate set is obtained by the optical tracking system measuring the calibration plate at different positions. This dynamically changing calibration plate provides a common reference benchmark for both the laser tracker and the optical tracking system in physical space, and also provides multi-source calibration data and reduces the accumulation of single-point errors. Furthermore, a target point coordinate set is obtained by the laser tracker measuring the target point of the optical tracking system. After determining the first and second coordinate sets, a first target transformation relationship between the first coordinate system of the laser tracker and the second coordinate system of the optical tracking system is determined based on the first and second coordinate sets. Then, using the first target transformation relationship and the calibration point coordinate set, a second target transformation relationship between the second coordinate system and the target point is determined, completing the calibration of the optical tracking system. Through the above embodiments, a unified coordinate system can be achieved, and large accumulated errors during station transitions can be avoided, thus improving scanning accuracy to a certain extent.

[0060] Figure 4 This is an application flowchart of the second target transformation relationship provided in the embodiments of this application. After completing the equipment calibration, it utilizes, as shown in... Figure 2 The second target conversion relationship determined in the illustrated embodiment enables the switching of the optical tracking system. For example... Figure 4 As shown, the steps include the following.

[0061] Step S401: Determine the first and second positions of the optical tracking system during the movement process.

[0062] In some embodiments of this application, if the scanned object is large and exceeds the scanning range of the optical tracking system during the scanning process, it is necessary to move the position of the optical tracking system. The optical tracking system is moved from a first position to a second position, wherein the second position can be a pre-set position or a randomly determined position, and this application does not limit this.

[0063] Step S402: Obtain the first coordinates of the target point obtained by the laser tracker measuring the target point when the optical tracking system is in the first position, and the second coordinates of the target point obtained by the optical tracking system measuring the target point when the optical tracking system is in the second position.

[0064] In some embodiments of this application, the optical tracking system includes a target point, which may be a marker point. When the optical tracking system is in a first position, a laser tracker measures the target point to obtain its first coordinates. When the optical tracking system is in a second position, the laser tracker measures the target point to obtain its second coordinates. An electronic device receives the first and second coordinates sent by the laser tracker.

[0065] Step S403: Based on the first coordinates of the target point, the second coordinates of the target point, and the transformation relationship between the second target and the second coordinate system, determine the position transformation relationship between the second coordinate system of the optical tracking system at the first position and the second coordinate system of the optical tracking system at the second position.

[0066] In some embodiments of this application, the position transformation relationship represents the coordinate transformation relationship between the second coordinate system of the optical tracking system at the first position and the second coordinate system of the optical tracking system at the second position. The first position can be understood as the position before the transfer, and the second position can be understood as the position after the transfer. An intermediate transformation relationship is calculated based on the first and second coordinates. The intermediate transformation relationship represents the transformation relationship when the target point moves from the position before the transfer to the position after the transfer in the first coordinate system of the laser tracker, describing the movement of the target point in the first coordinate system. An inverse transformation is performed on the second target transformation matrix corresponding to the second target transformation relationship to obtain the inverse matrix. The position transformation relationship is determined based on the intermediate transformation relationship, the second target transformation relationship, and the inverse matrix. This can be expressed by the formula: Where T2 represents the position transformation relationship, Represents the inverse matrix. This indicates an intermediate transformation relationship. This represents the second target transformation matrix corresponding to the second target transformation relationship. By relating the motion of the target point to the second coordinate system of the optical tracking system through the second target transformation relationship, the motion of the optical tracking system can be derived.

[0067] Step S404: When the optical tracking system is in the first position, acquire the first data of the scanner scanning the object to be tested.

[0068] In some embodiments of this application, the object to be tested can also be referred to as the object being scanned, which can be any device, a part within a device, a human model, or a vehicle, etc. This application does not limit the type of object to be tested; it can be any object that can be scanned. The scanner can scan the object to be tested in real time. When the optical tracking system is in the first position, the electronic device acquires the first data of the scanner scanning the object to be tested, which can be an image frame of the object to be tested.

[0069] Step S405: When the optical tracking system is in the second position, acquire the second data of the scanner scanning the object to be tested.

[0070] In some embodiments of this application, the second position may be an adjacent position to the first position. When the optical tracking system is in the second position, the electronic device acquires second data from the scanner scanning the object under test, which may be an image frame of the object under test.

[0071] Step S406: Based on the position transformation relationship, the first data and the second data are transformed to the first reference coordinate system.

[0072] In some embodiments of this application, the position transformation relationship can unify the position of the scanner being tracked by the optical tracking system before and after a station change to the same optical tracking system coordinate system. This allows the first and second data to be stitched together based on the scanner's pose in the same optical tracking system coordinate system, thereby unifying the first and second data to the same coordinate system. For example, unification to a first reference coordinate system can be determined within the second coordinate systems of optical tracking systems at different positions, with each optical tracking system at a specific position having its own corresponding second coordinate system.

[0073] The above embodiments enable large-scale expansion of the scanning space. Furthermore, they avoid accumulated station errors, improving scanning accuracy.

[0074] Figure 5 This is a flowchart illustrating the acquisition of the first coordinate set provided in an embodiment of this application. The first coordinate set can be determined using one laser tracker or multiple laser trackers. Figure 5 The diagram shows the process of determining the first coordinate set using multiple laser trackers, including the following steps.

[0075] Step S501: Obtain the first sub-coordinate set obtained by each of the multiple laser trackers measuring the calibration plate at different positions.

[0076] In some embodiments of this application, the scanning range of each laser tracker is limited, and a laser tracker can be set at multiple different locations to expand the scanning space. The calibration plate can move based on a preset step size. When the calibration plate enters the measurement range of any laser tracker, the laser tracker measures the calibration plate within the measurement range to obtain the first sub-coordinates of the calibration plate at any position within that measurement range. A single laser tracker can measure the first sub-coordinates corresponding to calibration plates at multiple positions. This application does not limit the number of first sub-coordinates measured by a single laser tracker; the number is greater than or equal to 1. The first sub-coordinates measured by each laser tracker are combined to obtain the first sub-coordinate set corresponding to each laser tracker.

[0077] Step S502: Based on the first sub-coordinate set corresponding to each laser tracker, determine the first relative positional relationship between the corresponding first coordinate systems of multiple laser trackers.

[0078] In some embodiments of this application, the measurement ranges of any adjacent laser trackers in each laser tracker at least partially overlap. Taking the first and second adjacent laser trackers as examples, the following describes... Figure 6 Describe it. For example... Figure 6 As shown, within the overlapping measurement range of the first and second laser trackers, there are positions A, B, and C where the calibration plate is located, where positions A and B are adjacent, and positions B and C are adjacent.

[0079] Obtain the coordinates K11 corresponding to position A, K12 corresponding to position B, and K13 corresponding to position C from the first sub-coordinate set of the first laser tracker. Determine the transformation relationship T11 based on coordinates K11 and K12, and determine the transformation relationship T12 based on coordinates K12 and K13.

[0080] Obtain the coordinates K21 corresponding to position A, K22 corresponding to position B, and K23 corresponding to position C from the first sub-coordinate set of the second laser tracker. Determine the transformation relationship T21 based on coordinates K21 and K22, and determine the transformation relationship T22 based on coordinates K22 and K23.

[0081] Based on transformation relationships T12, T11, T21, and T22, the transformation matrix between the coordinate systems of the first and second laser trackers is calculated, thus obtaining the first relative positional relationship. This can be expressed by the formulas: T11Y = T21Y, T12Y = T22Y. Here, Y represents the transformation matrix corresponding to the first relative positional relationship.

[0082] The first relative positional relationship between the corresponding first coordinate systems of multiple laser trackers can be determined using the above method.

[0083] Step S503: Based on the first relative position relationship, transform the first sub-coordinate set corresponding to each laser tracker to the second reference coordinate system to determine the first coordinate set.

[0084] In some embodiments of the application, based on the first relative positional relationship, the first sub-coordinate set corresponding to each laser tracker can be transformed to the first coordinate system corresponding to the same laser tracker, denoted as the second reference coordinate system, thereby obtaining the first coordinate set under the second reference coordinate system. Since the second reference coordinate system can be any one of the first coordinate systems corresponding to multiple laser trackers, therefore, as... Figure 2The first target transformation relationship shown in the embodiment can be determined by the first coordinate set and the second coordinate set under the second reference coordinate system, representing the transformation relationship between the second reference coordinate system and the second coordinate system.

[0085] Equipment relocation calibration involves not only changes between coordinate systems but also changes in equipment position. Therefore, the above embodiments can reduce the cumulative error that occurs during equipment calibration and improve the accuracy of equipment calibration to a certain extent.

[0086] Figure 7 This is a flowchart illustrating the acquisition of the first coordinate set provided in an embodiment of this application. For example... Figure 7 As shown, the second coordinate set can be determined using multiple optical tracking systems, such as... Figure 7 The steps shown are as follows.

[0087] Step S701: Obtain the second sub-coordinate set obtained by each optical tracking system in multiple optical tracking systems measuring the calibration plate at different positions.

[0088] In some embodiments of this application, the scanning range of a single optical tracking system is limited. To reduce the movement operations of the optical tracking system, multiple optical tracking systems can be used to complete the relocation calibration of the device, thereby reducing the cumulative error of subsequent optical tracking system relocations. Multiple optical tracking systems are set up in multiple different locations, and the calibration board can move based on a preset step size. When the calibration board enters the measurement range of any optical tracking system, the optical tracking system measures the calibration board within the measurement range, thereby obtaining the second sub-coordinates of the calibration board at any position within that measurement range. A single optical tracking system can measure the second sub-coordinates corresponding to calibration boards at multiple positions. This application does not limit the number of second sub-coordinates measured by a single optical tracking system; the number is greater than or equal to 1. The second sub-coordinates measured by each optical tracking system are combined to obtain the second sub-coordinate set corresponding to each optical tracking system.

[0089] Step S702: Based on the second sub-coordinate set corresponding to each optical tracking system, determine the second relative position relationship between the corresponding second coordinate systems of each optical tracking system.

[0090] In some embodiments of this application, the measurement ranges of any adjacent optical tracking systems in each optical tracking system at least partially overlap. Taking the first and second adjacent optical tracking systems as an example, the following describes... Figure 8 Describe it. For example... Figure 8As shown, within the measurement range where the first optical tracking system and the second optical tracking system overlap, there are positions A, B, and C where the calibration plate is located, where positions A and B are adjacent, and positions B and C are adjacent.

[0091] Obtain the coordinates U11 for position A, U12 for position B, and U13 for position C from the second sub-coordinate set of the first optical tracking system. Determine the transformation relationship H11 based on coordinates U11 and U12, and determine the transformation relationship H12 based on coordinates U12 and U13.

[0092] Obtain the coordinates U21 corresponding to position A, U22 corresponding to position B, and U23 corresponding to position C from the second sub-coordinate set of the second optical tracking system. Determine the transformation relationship H21 based on coordinates U21 and U22, and determine the transformation relationship H22 based on coordinates U22 and U23.

[0093] Based on transformation relations H12, H11, H21, and H22, the second relative positional relationship between the coordinate systems of the first and second optical tracking systems is calculated. This can be expressed by the formulas: H11Q = H21Q, H12Q = H22Q. Here, Q represents the transformation matrix corresponding to the second relative positional relationship.

[0094] The second relative positional relationship between the corresponding second coordinate systems of multiple optical tracking systems can be determined in the above manner.

[0095] Step S703: Based on the second relative position relationship, transform the second sub-coordinate set corresponding to each optical tracking system to the third reference coordinate system to determine the second coordinate set.

[0096] In some embodiments of the application, based on the second relative position relationship, the second sub-coordinate set corresponding to each optical tracking system can be transformed to the second coordinate system corresponding to the same optical tracking system, denoted as the third reference coordinate system, thereby obtaining the second coordinate set under the third reference coordinate system.

[0097] Since the third reference coordinate system can be any one of the corresponding second coordinate systems of multiple optical tracking systems, therefore, as Figure 2 The first target transformation relationship shown in the embodiment can be determined by the first coordinate set and the second coordinate set under the third reference coordinate system, representing the transformation relationship between the third reference coordinate system and the first coordinate system.

[0098] Equipment relocation calibration involves not only changes between coordinate systems but also changes in equipment position. Therefore, the above embodiments can reduce the cumulative error that occurs during equipment calibration and improve the accuracy of equipment calibration to a certain extent.

[0099] Figure 9 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. The device calibration method provided in this embodiment of the application is applied to an electronic device 10, which may be a computer device with a shooting function such as a mobile phone, tablet computer, laptop computer, or facial scanner.

[0100] The electronic device 10 includes a communication module 101, a memory 102, a processor 103, an input / output (I / O) interface 104, and a bus 105. The processor 103 is coupled to the communication interface 101, the memory 102, and the I / O interface 104 via the bus 105.

[0101] Communication module 101 may include a wired communication module and / or a wireless communication module. The wired communication module may provide one or more wired communication solutions such as Universal Serial Bus (USB) and Controller Area Network (CAN). The wireless communication module may provide one or more wireless communication solutions such as Wireless Fidelity (Wi-Fi), Bluetooth (BT), mobile communication networks, Frequency Modulation (FM), Near Field Communication (NFC), and Infrared (IR).

[0102] Memory 102 may include one or more random access memory (RAM) and one or more non-volatile memory (NVM). The RAM can be directly read and written by the processor 103 and can be used to store executable programs (such as machine instructions) of the operating system or other running programs, as well as user and application data. The RAM may include static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), etc.

[0103] Non-volatile memory can also store executable programs and user and application data, and can be pre-loaded into random access memory for direct reading and writing by the processor 110. Non-volatile memory can include disk storage devices and flash memory.

[0104] Memory 102 is used to store one or more computer programs. The one or more computer programs are configured to be executed by processor 103. The one or more computer programs include multiple instructions that, when executed by processor 103, can implement a device calibration method executed on electronic device 10.

[0105] In other embodiments, the electronic device 10 further includes an external memory interface for connecting to an external memory to expand the storage capacity of the electronic device 10.

[0106] Processor 103 may include one or more processing units, such as application processor (AP), modem processor, graphics processing unit (GPU), image signal processor (ISP), controller, video codec, digital signal processor (DSP), baseband processor, and / or neural network processing unit (NPU). These different processing units may be independent devices or integrated into one or more processors.

[0107] The processor 103 provides computing and control capabilities. For example, the processor 103 is used to execute computer programs stored in the memory 102 to implement the device calibration method described above.

[0108] I / O interface 104 is used to provide a channel for user input or output. For example, I / O interface 104 can be used to connect various input and output devices, such as mouse, keyboard, touch device, display screen, etc., so that users can enter information or visualize information.

[0109] Bus 105 is used at least to provide a channel for communication between communication modules 101, memory 102, processor 103, and I / O interface 104 in electronic device 10.

[0110] This application also provides a computer-readable storage medium storing a computer program, the computer program including program instructions, and the method implemented when the program instructions are executed can refer to the methods in the above embodiments of this application.

[0111] The computer-readable storage medium can be the internal memory of the electronic device described in the above embodiments, such as the hard disk or memory of the electronic device. Alternatively, the computer-readable storage medium can be an external storage device of the electronic device, such as a plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, etc., equipped on the electronic device.

[0112] In some embodiments, the computer-readable storage medium may include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application program required for at least one function, etc.; and the data storage area may store data created based on the use of the electronic device, etc.

[0113] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0114] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0115] In the embodiments provided in this application, it should be understood that the disclosed devices / terminal equipment and methods can be implemented in other ways. For example, the device / terminal equipment embodiments described above are merely illustrative. For instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling or direct coupling or communication connection may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0116] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0117] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A method for calibrating equipment, characterized in that, The method includes: Obtain the first set of coordinates obtained by the laser tracker measuring the calibration plate at different positions; The system acquires a second set of coordinates obtained by the optical tracking system measuring the calibration plate at different positions, and acquires a set of target point coordinates obtained by the laser tracker measuring the target point of the optical tracking system. Determining a first target transformation relationship between the first coordinate system of the laser tracker and the second coordinate system of the optical tracking system based on the first coordinate set and the second coordinate set includes: obtaining a first adjacent coordinate pair from the first coordinate set, wherein the first adjacent coordinate pair is determined based on any two adjacent positions of the calibration plate during its movement; obtaining a second adjacent coordinate pair from the second coordinate set, wherein the second adjacent coordinate pair is determined based on the arbitrary two adjacent positions; determining a first transformation relationship for each of the plurality of first adjacent coordinate pairs; determining a second transformation relationship for each of the plurality of second adjacent coordinate pairs; and determining the first target transformation relationship based on the first transformation relationship of each of the first adjacent coordinate pairs and the second transformation relationship of each of the second adjacent coordinate pairs. Based on the first target transformation relationship and the target point coordinate set, a second target transformation relationship between the second coordinate system and the target points is determined; Based on the second target conversion relationship, the calibration of the optical tracking system is completed.

2. The equipment calibration method according to claim 1, characterized in that, The optical tracking system includes a scanner, and the acquisition of a first coordinate set obtained by the laser tracker measuring a calibration plate at different positions includes: The scanner scans the calibration plate at different positions to obtain a set of scan coordinates; Based on the transformation relationship between the scanner's coordinate system and the second coordinate system, the scan coordinate set is transformed to the second coordinate system to obtain the second coordinate set.

3. The equipment calibration method according to claim 1, characterized in that, After calibrating the optical tracking system, the method further includes: Determine the first and second positions of the optical tracking system during its movement; The laser tracker measures the target point when the optical tracking system is in the first position, obtaining the first coordinates of the target point, and the optical tracking system measures the target point when the optical tracking system is in the second position, obtaining the second coordinates of the target point. Based on the first coordinates of the target point, the second coordinates of the target point, and the transformation relationship between the target point and the second target, the position transformation relationship between the second coordinate system of the optical tracking system at the first position and the second coordinate system of the optical tracking system at the second position is determined.

4. The equipment calibration method according to claim 3, characterized in that, The method further includes: When the optical tracking system is in the first position, first data of the scanner scanning the object to be tested is acquired; When the optical tracking system is in the second position, second data of the scanner scanning the object under test is acquired; Based on the position transformation relationship, the first data and the second data are transformed to a first reference coordinate system. The first reference coordinate system is determined from the second coordinate system of the optical tracking system at different positions. Each optical tracking system at each position has a corresponding second coordinate system.

5. The equipment calibration method according to claim 1, characterized in that, The first coordinate set obtained by acquiring the laser tracker from measurements of calibration plates at different positions includes: A first sub-coordinate set is obtained by each of the multiple laser trackers measuring the calibration plate at different positions, wherein the different positions are within the common field of view of the multiple laser trackers and the optical tracking system; Based on the first sub-coordinate set corresponding to each laser tracker, the first relative positional relationship between the corresponding first coordinate systems of the multiple laser trackers is determined; Based on the first relative positional relationship, the first sub-coordinate set corresponding to each laser tracker is transformed to the second reference coordinate system to determine the first coordinate set; wherein, the second reference coordinate system is determined from the corresponding first coordinate system of the multiple laser trackers; Accordingly, determining the first target transformation relationship between the first coordinate system of the laser tracker and the second coordinate system of the optical tracking system based on the first coordinate set and the second coordinate set includes: Based on the first coordinate set and the second coordinate set, a first target transformation relationship between the second reference coordinate system and the second coordinate system is determined.

6. The equipment calibration method according to claim 1, characterized in that, The acquisition of the second coordinate set obtained by the optical tracking system from measurements of the calibration plate at different positions includes: A second sub-coordinate set is obtained by each of the multiple optical tracking systems measuring the calibration plate at different positions, wherein the different positions are within the common field of view of the multiple optical tracking systems and the laser tracker; Based on the second sub-coordinate set corresponding to each optical tracking system, determine the second relative positional relationship between the corresponding second coordinate systems of each optical tracking system; Based on the second relative position relationship, the second sub-coordinate set corresponding to each optical tracking system is transformed to the third reference coordinate system to determine the second coordinate set; wherein, the third reference coordinate system is determined from the second coordinate system corresponding to each optical tracking system; Accordingly, determining the first target transformation relationship between the first coordinate system of the laser tracker and the second coordinate system of the optical tracking system based on the first coordinate set and the second coordinate set includes: Based on the first coordinate set and the second coordinate set, a first target transformation relationship between the third reference coordinate system and the first coordinate system is determined.

7. A device calibration system, characterized in that, include: A laser tracker is used to measure calibration plates at different positions to obtain a first coordinate set; An optical tracking system is used to measure the calibration plate at different positions to obtain a second coordinate set, and to acquire the target point coordinate set obtained by the laser tracker measuring the target point of the optical tracking system. An electronic device is used to determine a first target transformation relationship between the first coordinate system of the laser tracker and the second coordinate system of the optical tracking system based on the first coordinate set and the second coordinate set, including: obtaining a first adjacent coordinate pair from the first coordinate set, wherein the first adjacent coordinate pair is determined based on any two adjacent positions of the calibration plate during the movement process; Obtain a second adjacent coordinate pair from the second coordinate set, the second adjacent coordinate pair being determined based on any two adjacent positions; determine a first transformation relationship for each of the multiple first adjacent coordinate pairs; determine a second transformation relationship for each of the multiple second adjacent coordinate pairs; determine a first target transformation relationship based on the first transformation relationship of each of the first adjacent coordinate pairs and the second transformation relationship of each of the second adjacent coordinate pairs. The electronic device is further configured to determine a second target transformation relationship between the second coordinate system and the target points based on the first target transformation relationship and the target point coordinate set; The electronic device is also used to calibrate the optical tracking system based on the second target conversion relationship.

8. An electronic device, characterized in that, The electronic device includes a processor and a memory, the processor being configured to execute a computer program stored in the memory to implement the device calibration method as described in any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores at least one instruction, which, when executed by a processor, implements the device calibration method as described in any one of claims 1 to 6.

Images