Equipment calibration method and system, electronic equipment and storage medium

Abstract

The invention provides an equipment calibration method and system, electronic equipment and a storage medium. The equipment calibration method comprises the following steps: acquiring a first coordinate set obtained by measuring calibration plates at different positions by a laser tracker; acquiring a second coordinate set obtained by measuring the calibration plates at different positions by the optical tracking system, and acquiring a target point coordinate set obtained by measuring target points of the optical tracking system by the laser tracker; determining a first target conversion relation 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; based on the first target conversion relation and a target point coordinate set, determining a second target conversion relation between the second coordinate system and the target point; and completing calibration of the laser tracker and the optical tracking system based on the second target conversion relation. According to the method, the equipment calibration precision can be improved.

Description

Technical Field

[0001] The present application relates to the field of scanning, and in particular to a device calibration method, system, electronic device and storage medium. Background Art

[0002] When scanning an object using a 3D scanning system, a tracker is required to position the scanner in real time to obtain scan data of the object. Due to the limited measurement range of the tracker, it is necessary to affix marker points to the object or to affix marker points in a common area and to move the tracker to complete the conversion between different coordinate systems. When the object to be scanned is large, the tracker needs to be moved multiple times to collect the scan data of the scanner measuring the object. Therefore, if the transfer station calibration is completed by affixing marker points, multiple transfer station errors will accumulate during subsequent scanning processes, affecting the accuracy of the scan. Summary of the Invention

[0003] The embodiments of the present application disclose a device calibration method, system, electronic device and storage medium, which solve the technical problem of large cumulative errors during station transfer.

[0004] The present application provides a device calibration method, which includes: obtaining a first coordinate set obtained by measuring a calibration plate at different positions with a laser tracker; obtaining a second coordinate set obtained by measuring the calibration plate at different positions with an optical tracking system, and obtaining a target point coordinate set obtained by measuring a target point of the optical tracking system with the laser tracker; 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 calibration of the optical tracking system based on the second target transformation relationship.

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

[0006] In some embodiments of the present 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, the first adjacent coordinate pair being determined based on any two adjacent positions of the calibration plate during movement; obtaining a second adjacent coordinate pair from the second coordinate set, the second adjacent coordinate pair being determined based on the any two adjacent positions; determining the first transformation relationship of each first adjacent coordinate pair according to each first adjacent coordinate pair in a plurality of first adjacent coordinate pairs; determining the second transformation relationship of each second adjacent coordinate pair according to each second adjacent coordinate pair in a plurality of second adjacent coordinate pairs; and determining the first target transformation relationship according to the first transformation relationship of each first adjacent coordinate pair and the second transformation relationship of each second adjacent coordinate pair.

[0007] In some embodiments of the present application, after completing the calibration of the optical tracking system, the method further includes: determining the first position and the second position of the optical tracking system during the movement; obtaining the first coordinate 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 coordinate of the target point obtained by measuring the target point when the optical tracking system is in the second position; based on the first coordinate of the target point, the second coordinate of the target point and the second target conversion relationship, determining the position conversion 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.

[0008] In some embodiments of the present application, the method further includes: when the optical tracking system is in the first position, obtaining first data of the scanner scanning the object to be measured; when the optical tracking system is in the second position, obtaining second data of the scanner scanning the object to be measured; based on the position conversion relationship, converting the first data and the second data to a first reference coordinate system, the first reference coordinate system is determined from the second coordinate systems of the optical tracking systems at different positions, and the optical tracking system at each position has a corresponding second coordinate system.

[0009] In some embodiments of the present application, acquiring a first coordinate set obtained by measuring a calibration plate at different positions using a laser tracker includes: acquiring a first sub-coordinate set obtained by measuring the calibration plate at different positions using each laser tracker of a plurality of laser trackers, wherein the different positions are within a common field of view of the plurality of laser trackers and the optical tracking system; determining a first relative position relationship between first coordinate systems corresponding to the plurality of laser trackers based on the first sub-coordinate set corresponding to each laser tracker; and converting the first sub-coordinate set corresponding to each laser tracker into a second reference coordinate system based on the first relative position relationship to determine the first coordinate set; wherein the second reference coordinate system is determined from the first coordinate systems corresponding to the plurality of laser trackers; accordingly, 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: determining a 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 the present application, acquiring the second coordinate set obtained by measuring the calibration plate at different positions by the optical tracking system includes: acquiring a second sub-coordinate set obtained by each optical tracking system of a plurality of optical tracking systems measuring the calibration plate at different positions, wherein the different positions are within a common field of view of the plurality of trackers and the laser tracker; determining a second relative position relationship between the second coordinate systems corresponding to each optical tracking system based on the second sub-coordinate set corresponding to each optical tracking system; and transforming the second sub-coordinate set corresponding to each optical tracking system into a third reference coordinate system based on the second relative position relationship 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 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: determining a 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] The present application also provides a device calibration system, including: a laser tracker, used to measure a calibration plate at different positions to obtain a first coordinate set; an optical tracking system, used to measure the calibration plate at different positions to obtain a second coordinate set, and obtain a target point coordinate set obtained by the laser tracker measuring the target point of the optical tracking system; an electronic device, 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; the electronic device is also used 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; the electronic device is also used to complete the calibration of the optical tracking system based on the second target transformation relationship.

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

[0013] The present application also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the device calibration method is implemented.

[0014] In the device calibration method provided in this application, a first coordinate set is obtained by measuring a calibration plate at different positions using a laser tracker, and a second coordinate set is obtained by measuring the calibration plate at different positions using an optical tracking system. The dynamically changing position of the calibration plate provides a common reference datum for the laser tracker and the optical tracking system in physical space, provides multi-source calibration data, and reduces single-point error accumulation. In addition, a target point coordinate set is obtained by measuring a target point of the optical tracking system using the laser tracker. After determining the first coordinate set and the second coordinate set, 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 coordinate set and the second coordinate set. The second target transformation relationship between the second coordinate system and the target point is then determined using the first target transformation relationship and the target point coordinate set, completing the calibration of the optical tracking system. Through the above embodiment, a coordinate system can be achieved, and large cumulative errors that occur during station transfer can be avoided, thereby improving scanning accuracy to a certain extent. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0016] Figure 2 This is a flow chart of the device calibration method provided in an embodiment of the present application.

[0017] Figure 3 It is a schematic diagram of the application scenario provided by the embodiment of the present application.

[0018] Figure 4 This is an application flow chart of the second target conversion relationship provided in an embodiment of the present application.

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

[0020] Figure 6 This is a measurement diagram of multiple laser trackers provided in an embodiment of the present application.

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

[0022] Figure 8 This is a measurement diagram of multiple optical tracking systems provided in an embodiment of the present application.

[0023] Figure 9 It is a structural diagram of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0024] To facilitate understanding, some illustrations of concepts related to the embodiments of the present application are given for reference.

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

[0026] In the automotive, marine, and aerospace industries, 3D scanning systems are commonly used to acquire 3D data. A 3D scanning system consists of a tracker and a scanner (such as a handheld scanner). The tracker can include a laser tracker and an optical tracking system. The optical tracking system can position the handheld scanner in real time to scan objects without markers (such as large workpieces), thereby acquiring 3D data corresponding to the scanned object. The optical tracking system has a limited measurement range, typically between 3m and 10m. If the object being scanned is large and exceeds the optical tracking system's measurement range, the optical tracking system must be relocated to complete 3D data acquisition.

[0027] Before the actual scanning work, it is necessary to complete the conversion between different coordinate systems to complete the transfer calibration. In the related art, it is necessary to paste markers on the object or paste markers in the public area, and complete the conversion between different coordinate systems by moving the position of the optical tracking system. However, this method cannot ensure the scanning accuracy of large scenes. When multiple transfers are required, it will lead to the accumulation of multiple transfer errors, affecting the subsequent transfer scanning accuracy of the optical tracking system.

[0028] In order to solve the technical problem of large cumulative errors during station transfer, the embodiments of the present application provide a device calibration method, system, electronic device and storage medium, which uses a laser tracker to assist the optical tracking system to complete the station transfer calibration, realize the unification of the first coordinate system of the laser tracker and the second coordinate system of the optical tracking system, and ensure the scanning accuracy of large workpieces. In addition, the station transfer calibration between the laser tracker and the optical tracking system is completed by calibrating the dynamic position change, which can improve the accuracy of the station transfer calibration. In the subsequent scanning process, the cumulative error after multiple station transfers can be avoided, which improves the subsequent scanning accuracy to a certain extent. The architecture of the device calibration system of the present application is first described below.

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

[0030] The electronic device 10 may include a device with communication capabilities, such as a laptop computer, a tablet computer, a programmable logic controller (PLC), and a human-machine interface (HMI) with touch input capabilities. It may also include a device simulated by a virtual machine or simulator. The electronic device 10 is used to receive data sent by the laser tracker 20 and the optical tracking system 30 and perform calculations on the data to complete the device's transfer calibration.

[0031] The laser tracker 20 is a high-precision, large-scale measuring instrument capable of performing precise point measurements across large scenes. It is used to measure the coordinates of markers on a calibration plate. Markers, also known as reflective markers, can be objects of various shapes and materials. The laser tracker 20 can transmit the coordinates of the markers on the calibration plate to the electronic device 10.

[0032] The optical tracking system 30 can directly measure the coordinates of the marker points on the calibration plate through the optical tracker 310. The optical tracking system 30 can send the coordinates of the marker points on the calibration plate to the electronic device 10. In addition, the optical tracking system 30 can be provided with a target point. After completing the device calibration, the laser tracker 20 can also measure the coordinates of the target point and send the measured coordinates of the target point to the electronic device 10.

[0033] The optical tracking system 30 can also measure the coordinates of the marker points on the calibration plate using the scanner 320. The optical tracker 310 and scanner 320 in the optical tracking system 30 can be two independently operating devices that can achieve a communication connection, or they can be two sub-devices belonging to the same system (for example, a tracking scanner). They can be assembled to operate collaboratively or disassembled to operate independently. This application does not limit the device form, operation mode, etc. of the optical tracker 310 and scanner 320.

[0034] In the application scenario of the device calibration system, in one example, a laser tracker 20 and an optical tracking system 30 can be fixed at a preset position respectively. In another example, multiple optical tracking systems 30 and / or multiple laser trackers 20 can be fixed at a preset position. Taking the example of fixing a laser tracker 20 and an optical tracking system 30 at a preset position, 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 sets corresponding to the calibration plates at different positions. The optical tracking system 30 can measure the coordinate sets corresponding to the calibration plates at different positions through the optical tracker 310, and can also obtain the coordinate sets 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 calibrating the optical tracking system 30.

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

[0036] Figure 2 This is a flow chart of a device calibration method provided in an embodiment of the present application, which is applied to electronic devices (such as Figure 1 According to different requirements, the order of the steps in the flowchart can be changed, and some steps can be omitted.

[0037] Step S201 : obtaining a first coordinate set obtained by measuring calibration plates at different positions with a laser tracker.

[0038] In some embodiments of the present application, the laser tracker can be pre-fixed in position, meaning that its position relative to the ground remains unchanged during device calibration. A calibration plate is placed within the laser tracker's measurement range. The plate can be equipped with a target holder, on which markers can be placed. These markers can be high-precision reflective markers, such as hubbs.

[0039] In some embodiments of the present application, the calibration plate can be moved manually by the user, and can also be assisted by other self-moving devices to move the calibration plate, and this application is not limited to this. Move the calibration plate according to a pre-set moving step length, and record the multiple positions reached by the calibration plate. In one example, assuming the moving step length is 5m, the calibration plate is moved to position A according to a length of 5m. At the position of 5m, move another 5m to position B, then position A is at a position 5m away from the starting point of movement, and position B is at a position 10m away from the starting point of movement. The above are just examples, the moving step length can be set according to actual needs, and there can be multiple different moving step lengths, and this application is not limited to this. In addition, there is no limit on the number of movements of the calibration plate, and there can be more movements than in the above example. In another example, multiple calibration plates can also be set within the measurement range of the laser tracker, and this application does not limit the number of calibration plates.

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

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

[0042] In some embodiments of the present application, the optical tracking system can be pre-fixed in position, i.e., the position of the optical tracking system relative to the ground does not change during the device calibration process. The position of the optical tracking system is different from the position 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 overlapping range, i.e., the optical tracking system and the laser tracker can simultaneously detect the same calibration plate.

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

[0044] In other embodiments of the present application, the optical tracking system may include a scanner, which can scan calibration plates at different locations using the scanner to obtain a scanned coordinate set. Based on a conversion relationship between the scanner's coordinate system and the optical tracking system's coordinate system (e.g., a second coordinate system), the scanned coordinate set is converted to the second coordinate system, thereby obtaining a second coordinate set in the second coordinate system.

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

[0046] In order to better understand the acquisition process of step S201 and step S202, Figure 3 Describe. Figure 3 As shown, a calibration plate with calibration points set on it is placed within the common field of view of the laser tracker 20 and the optical tracking system 30. Based on the preset movement direction and movement step length (which can also be a random step length), the calibration plate is moved, passing through position A, position B, position C, ..., position N in sequence. Since the positions of the laser tracker 20 and the optical tracking system 30 remain unchanged, the laser tracker 20 can record the target point on the optical tracking system 30 at any time ( Figure 3 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 coordinates in 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 coordinates in the second coordinate system of the optical tracking system 30. This process is repeated until the coordinates of N positions in the coordinate system of the laser tracker 20 and the coordinates in the second coordinate system of the optical tracking system 30 are recorded.

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

[0048] Step S203 : 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.

[0049] In some embodiments of the present 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, multiple consecutive first adjacent coordinate pairs are obtained from the first coordinate set, and multiple 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 the movement. In one example, it is determined that there are continuous positions A, B, and C in the calibration plate during the movement, then position A is adjacent to position B, and position B is adjacent to position C. The coordinates P11 corresponding to position A, the coordinates P12 corresponding to position B, and the coordinates P13 corresponding to position C are obtained from the first coordinate set. The coordinates P11 corresponding to position A and the coordinates P12 corresponding to position B can constitute a first first adjacent coordinate pair. The coordinates P12 corresponding to position B and the coordinates P13 corresponding to position C can constitute a second first adjacent coordinate pair. The first first adjacent coordinate pair and the second first adjacent coordinate pair include the same coordinates P12.

[0051] Similarly, the second adjacent coordinate pair is also determined based on the above-mentioned continuous positions A, B, and C. That is, the two adjacent positions for determining the first adjacent coordinates are the same as the two positions for determining the second adjacent coordinates, ensuring that the first adjacent coordinate pair and the second adjacent coordinate pair are determined based on the same two adjacent positions. In one example, coordinate P21 corresponding to position A, coordinate P22 corresponding to position B, and coordinate P23 corresponding to position C are obtained from the second coordinate set. If positions A and B are adjacent, coordinates P21 and P22 are used as the first second adjacent coordinate pair. If positions B and C are adjacent, coordinates P22 and P23 are used as the second second adjacent coordinate pair.

[0052] In some embodiments of the present application, after determining multiple first adjacent coordinate pairs, a first transformation relationship is determined for each of the multiple first adjacent coordinate pairs. The first transformation relationship represents the transformation relationship between coordinates of adjacent first positions when transforming to coordinates of a second position 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 the plurality of second adjacent coordinate pairs, a second conversion relationship is determined for each of the plurality of second adjacent coordinate pairs. Continuing with the above example, the second conversion relationship S21 is calculated based on the first second adjacent coordinate pair, and the second conversion 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 with the above example, 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. Where X represents the first target transformation matrix, which is used to determine the first target transformation relationship.

[0055] Step S204: 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.

[0056] In some embodiments of the present 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 measurement value corresponding to the target point 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 point can be calculated, and the second target transformation relationship can be determined 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: completing calibration of the optical tracking system based on the second target conversion relationship.

[0058] In some embodiments of the present 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 second target transformation relationship can be used to determine the location of the optical tracking system, as well as the transformation relationships between the second coordinate systems corresponding to optical tracking systems at different locations, thereby achieving coordinate system unification.

[0059] Through the above embodiment, a first coordinate set is obtained by measuring a calibration plate at different positions using a laser tracker, and a second coordinate set is obtained by measuring the calibration plate at different positions using an optical tracking system. The dynamically changing position of the calibration plate provides a common reference datum for the laser tracker and the optical tracking system in physical space, provides multi-source calibration data, and reduces single-point error accumulation. Furthermore, a target point coordinate set is obtained by measuring a target point of the optical tracking system using the laser tracker. After determining the first coordinate set and the second coordinate set, 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 coordinate set and the second coordinate set. The second target transformation relationship between the second coordinate system and the target point is then determined using the first target transformation relationship and the calibration point coordinate set, completing the calibration of the optical tracking system. Through the above embodiment, a coordinate system can be achieved, and large cumulative errors that occur during station transfer can be avoided, thereby improving scanning accuracy to a certain extent.

[0060] Figure 4 This is the application flow chart of the second target conversion relationship provided by the embodiment of this application. After completing the equipment calibration, use Figure 2 The second target conversion relationship determined in the embodiment shown realizes the transfer of the optical tracking system. Figure 4 As shown, the following steps are included.

[0061] Step S401: determining a first position and a second position of the optical tracking system during movement.

[0062] In some embodiments of the present application, during the scanning process of an object, if the object is large and exceeds the scanning range of the optical tracking system, the optical tracking system needs to be moved from a first position to a second position. The second position can be a pre-set position or a randomly determined position, which is not limited by the present application.

[0063] Step S402 : acquiring a first coordinate of a target point obtained by measuring the target point with a laser tracker when the optical tracking system is at a first position, and a second coordinate of the target point obtained by measuring the target point with the optical tracking system at a second position.

[0064] In some embodiments of the present 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, the laser tracker measures the target point to obtain first coordinates of the target point. When the optical tracking system is in a second position, the laser tracker measures the target point to obtain second coordinates of the target point. An electronic device receives the first and second coordinates transmitted by the laser tracker.

[0065] Step S403 : determining a position conversion 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 based on the first coordinate of the target point, the second coordinate of the target point and the second target conversion relationship.

[0066] In some embodiments of the present application, the position conversion relationship represents the coordinate conversion 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. Among them, the first position can be understood as the position before the transfer station, and the second position can be understood as the position after the transfer station. According to the first coordinate and the second coordinate, the intermediate conversion relationship is calculated. The intermediate conversion relationship represents the conversion relationship when the position before the transfer station moves to the position after the transfer station in the first coordinate system of the laser tracker, and the intermediate conversion relationship describes the movement of the target point in the first coordinate system. The second target conversion matrix corresponding to the second target conversion relationship is inversely transformed to obtain an inverse matrix. According to the intermediate conversion relationship, the second target conversion relationship and the inverse matrix, the position conversion relationship is determined. It can be expressed as follows: , where T2 represents the position conversion relationship, represents the inverse matrix, Indicates the intermediate conversion relationship, The second target transformation matrix corresponding to the second target transformation relationship is represented. Through the second target transformation relationship, the motion of the target base point is associated with the second coordinate system of the optical tracking system, thereby deducing the motion of the optical tracking system.

[0067] Step S404 : when the optical tracking system is at the first position, obtaining first data of the object to be measured scanned by the scanner.

[0068] In some embodiments of the present application, the object to be measured may also be referred to as a scanned object, and may be any device, a part within a device, a human figure, a vehicle, or the like. The present application does not limit the type of the object to be measured, and the object may be any object that can be scanned. The scanner may scan the object to be measured in real time. When the optical tracking system is in a first position, the electronic device obtains first data obtained by the scanner from scanning the object to be measured. The first data may be an image frame of the object to be measured.

[0069] Step S405 : when the optical tracking system is at the second position, obtaining second data of the object to be measured scanned by the scanner.

[0070] In some embodiments of the present application, the second position may be a position adjacent to the first position. When the optical tracking system is at the second position, the electronic device obtains second data of the scanner scanning the object to be measured, and the second data may be an image frame of the object to be measured.

[0071] Step S406 : transforming the first data and the second data into a first reference coordinate system based on the position transformation relationship.

[0072] In some embodiments of the present application, the position conversion relationship can unify the position tracked by the scanner before and after the optical tracking system is transferred to the same optical tracking system coordinate system. The first data and the second data can then be spliced based on the position of the scanner in the same optical tracking system coordinate system, thereby unifying the first data and the second data to the same coordinate system. For example, the first reference coordinate system can be determined in 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.

[0073] Through the above embodiment, a large-scale expansion of a wide range of scanning space can be achieved. In addition, the cumulative transfer error can be avoided, thereby improving the scanning accuracy.

[0074] Figure 5 This is a flowchart of obtaining the first coordinate set provided by the embodiment of the present application. The first coordinate set can be determined using one laser tracker or multiple laser trackers. Figure 5 The figure shows a situation where multiple laser trackers determine a first coordinate set, which includes the following steps.

[0075] Step S501 : obtaining a first sub-coordinate set obtained by measuring a calibration plate at a different position by each of a plurality of laser trackers.

[0076] In some embodiments of the present application, the scanning range of each laser tracker is limited, and a laser tracker can be set at multiple different positions to expand the scanning space. The calibration plate can be moved 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, thereby obtaining the first sub-coordinate of the calibration plate within the measurement range when it is at any position. Among them, a laser tracker can measure the first sub-coordinate corresponding to the calibration plate at multiple positions. The present application does not limit the number of first sub-coordinates measured by a laser tracker, and the number is greater than or equal to 1. The first sub-coordinates measured by each laser tracker are combined to obtain a first sub-coordinate set corresponding to each laser tracker.

[0077] Step S502 : determining a first relative position relationship between first coordinate systems corresponding to the plurality of laser trackers based on a first sub-coordinate set corresponding to each laser tracker.

[0078] In some embodiments of the present application, any adjacent laser trackers in each laser tracker have at least partially overlapping measurement ranges. Taking the adjacent first laser tracker and the second laser tracker as an example, the following is combined with Figure 6 Describe. Figure 6 As shown, within the overlapping measurement range of the first laser tracker and the second laser tracker, there are positions A, B, and C where the calibration plate is located, wherein position A is adjacent to position B, and position B is adjacent to position C.

[0079] From the first sub-coordinate set of the first laser tracker, coordinates K11 corresponding to position A, K12 corresponding to position B, and K13 corresponding to position C are obtained. A transformation relationship T11 is determined based on coordinates K11 and K12, and a transformation relationship T12 is determined based on coordinates K12 and K13.

[0080] From the first sub-coordinate set of the second laser tracker, obtain coordinates K21 corresponding to position A, K22 corresponding to position B, and K23 corresponding to position C. Determine transformation relationship T21 based on coordinates K21 and K22, and determine 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 system of the first laser tracker and the coordinate system of the second laser tracker is calculated, thereby obtaining a first relative position relationship. This is expressed as: T11Y = T21Y, T12Y = T22Y. Y represents the transformation matrix corresponding to the first relative position relationship.

[0082] In the above manner, the first relative position relationship between the first coordinate systems corresponding to the plurality of laser trackers can be determined.

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

[0084] In some embodiments of the application, based on the first relative position relationship, the first sub-coordinate set corresponding to each laser tracker can be converted to the first coordinate system corresponding to the same laser tracker, which is recorded as the second reference coordinate system, thereby obtaining the first coordinate set in the second reference coordinate system. Since the second reference coordinate system can be any first coordinate system corresponding to multiple laser trackers, if Figure 2The first target conversion relationship shown in the illustrated embodiment can be determined by the first coordinate set and the second coordinate set in the second reference coordinate system, indicating the conversion relationship between the second reference coordinate system and the second coordinate system.

[0085] The station transfer calibration of the device involves not only changes between coordinate systems, but also changes in the device position. Therefore, the above embodiment can reduce the cumulative error occurring during the device calibration process and improve the accuracy of the device calibration to a certain extent.

[0086] Figure 7 This is a flowchart of obtaining the first coordinate set provided by the embodiment of this application. Figure 7 As shown, the second set of coordinates can be determined by multiple optical tracking systems, such as Figure 7 The following steps are included.

[0087] Step S701: obtaining a second sub-coordinate set obtained by each of a plurality of optical tracking systems measuring a calibration plate at a different position.

[0088] In some embodiments of the present application, the scanning range of an optical tracking system is limited. In order to reduce the movement operation of the optical tracking system, multiple optical tracking systems can be used to complete the station transfer calibration of the device, thereby reducing the cumulative error of the subsequent optical tracking system station transfer. Multiple optical tracking systems are set at multiple different positions, and the calibration plate can be moved based on a preset step size. When the calibration plate enters the measurement range of any optical tracking system, the optical tracking system measures the calibration plate within the measurement range to obtain the second sub-coordinate of the calibration plate within the measurement range when it is at any position. Among them, an optical tracking system can measure the second sub-coordinate corresponding to the calibration plate at multiple positions. The present application does not limit the number of second sub-coordinates measured by an optical tracking system, and the number is greater than or equal to 1. The second sub-coordinates measured by each optical tracking system are combined to obtain a set of second sub-coordinates corresponding to each optical tracking system.

[0089] Step S702: determining a second relative position relationship between the second coordinate systems corresponding to each optical tracking system based on the second sub-coordinate set corresponding to each optical tracking system.

[0090] In some embodiments of the present application, any adjacent optical tracking systems in each optical tracking system have at least partially overlapping measurement ranges. Figure 8 Describe. Figure 8As shown, within the overlapping measurement range of the first optical tracking system and the second optical tracking system, there are positions A, B and C where the calibration plate is located, wherein position A is adjacent to position B, and position B is adjacent to position C.

[0091] From the second sub-coordinate set of the first optical tracking system, coordinates U11 corresponding to position A, U12 corresponding to position B, and U13 corresponding to position C are obtained. A conversion relationship H11 is determined based on coordinates U11 and U12, and a conversion relationship H12 is determined based on coordinates U12 and U13.

[0092] From the second sub-coordinate set of the second optical tracking system, coordinates U21 corresponding to position A, U22 corresponding to position B, and U23 corresponding to position C are obtained. A transformation relationship H21 is determined based on coordinates U21 and U22, and a transformation relationship H22 is determined based on coordinates U22 and U23.

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

[0094] In the above manner, the second relative position relationship between the second coordinate systems corresponding to the multiple optical tracking systems can be determined.

[0095] Step S703: Based on the second relative position relationship, the second sub-coordinate set corresponding to each optical tracking system is converted into a third reference coordinate system to determine a 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 converted to the second coordinate system corresponding to the same optical tracking system, recorded as the third reference coordinate system, thereby obtaining the second coordinate set in the third reference coordinate system.

[0097] Since the third reference coordinate system can be any second coordinate system among the second coordinate systems corresponding to the plurality of optical tracking systems, Figure 2 The first target conversion relationship shown in the illustrated embodiment can be determined by the first coordinate set and the second coordinate set in the third reference coordinate system, indicating the conversion relationship between the third reference coordinate system and the first coordinate system.

[0098] The station transfer calibration of the device involves not only changes between coordinate systems, but also changes in the device position. Therefore, the above embodiment can reduce the cumulative error occurring during the device calibration process and improve the accuracy of the device calibration to a certain extent.

[0099] Figure 9 The device calibration method provided in the embodiment of the present application is applied to an electronic device 10, which can be a computer device with a camera 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] The 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 memories (RAMs) and one or more non-volatile memories (NVMs). RAM can be directly read and written by processor 103 and can be used to store executable programs (e.g., machine instructions) for the operating system or other running programs, as well as user and application data. 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] The non-volatile memory can also store executable programs and user and application data, etc., and can be pre-loaded into the random access memory for direct reading and writing by the processor 110. The non-volatile memory can include disk storage devices and flash memory.

[0104] The memory 102 is configured to store one or more computer programs. The one or more computer programs are configured to be executed by the processor 103. The one or more computer programs include multiple instructions. When the multiple instructions are executed by the processor 103, the device calibration method executed on the electronic device 10 can be implemented.

[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] The processor 103 may include one or more processing units. For example, the processor 103 may include an application processor (AP), a modem processor, a graphics processing unit (GPU), an image signal processor (ISP), a controller, a video codec, a digital signal processor (DSP), a baseband processor, and / or a neural-network processing unit (NPU). The 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 a computer program stored in the memory 102 to implement the above-mentioned device calibration method.

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

[0109] The bus 105 is at least used to provide a channel for mutual communication among the communication module 101 , the memory 102 , the processor 103 , and the I / O interface 104 in the electronic device 10 .

[0110] An embodiment of the present application further provides a computer-readable storage medium, on which a computer program is stored. The computer program includes program instructions. The method implemented when the program instructions are executed can refer to the methods in the above-mentioned embodiments of the present application.

[0111] The computer-readable storage medium may be an internal memory of the electronic device described in the above embodiment, such as a hard disk or memory of the electronic device. The computer-readable storage medium may also be an external storage device of the electronic device, such as a plug-in hard disk, a smart memory card (SMC), a secure digital (SD) card, a flash memory 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, applications required for at least one function, etc.; the data storage area may store data created according to the use of the electronic device, etc.

[0113] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant description of other embodiments.

[0114] Those skilled in the art will appreciate that the units and algorithm steps of each example 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 performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel 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 example, the division of the modules or units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0116] The units described as separate components may or may not be physically separate, and 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 these units may 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 the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present application, and should all be included in the scope of protection of the present application.

Claims

1. A device calibration method, characterized in that: The method comprises: Obtaining a first coordinate set obtained by measuring a calibration plate at different positions using a laser tracker; Acquire a second coordinate set obtained by measuring the calibration plate at different positions using an optical tracking system, and acquire a target point coordinate set obtained by measuring the target point of the optical tracking system using the laser tracker; 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; Based on the second target conversion relationship, the calibration of the optical tracking system is completed.

2. The device calibration method according to claim 1, characterized in that: The optical tracking system includes a scanner, and the step of obtaining a first coordinate set obtained by measuring a calibration plate at different positions with a laser tracker includes: Obtaining the scanner to scan the calibration plate at different positions to obtain a scanning coordinate set; Based on the conversion relationship between the coordinate system of the scanner and the second coordinate system, the scanning coordinate set is converted to the second coordinate system to obtain the second coordinate set.

3. The device calibration method according to claim 1, characterized in that: The determining, based on the first coordinate set and the second coordinate set, a first target transformation relationship between a first coordinate system of the laser tracker and a second coordinate system of the optical tracking system comprises: Acquire a first adjacent coordinate pair from the first coordinate set, where the first adjacent coordinate pair is determined based on any two adjacent positions of the calibration plate during movement; Acquire a second adjacent coordinate pair from the second coordinate set, where the second adjacent coordinate pair is determined based on the arbitrary two adjacent positions; determining, according to each first adjacent coordinate pair in the plurality of first adjacent coordinate pairs, a first conversion relationship for each first adjacent coordinate pair; determining, according to each second adjacent coordinate pair in the plurality of second adjacent coordinate pairs, a second conversion relationship for each second adjacent coordinate pair; The first target conversion relationship is determined according to the first conversion relationship of each first adjacent coordinate pair and the second conversion relationship of each second adjacent coordinate pair.

4. The device calibration method according to claim 1, characterized in that: After completing the calibration of the optical tracking system, the method further includes: determining a first position and a second position of the optical tracking system during the movement; Acquire a first coordinate of the target point obtained by measuring the target point with the laser tracker when the optical tracking system is in the first position, and a second coordinate of the target point obtained by measuring the target point with the optical tracking system in the second position; Based on the first coordinate of the target point, the second coordinate of the target point and the second target conversion relationship, a position conversion 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.

5. The device calibration method according to claim 4, characterized in that: The method further comprises: When the optical tracking system is at the first position, obtaining first data of the object to be measured scanned by the scanner; When the optical tracking system is at the second position, obtaining second data of the object to be measured scanned by the scanner; Based on the position conversion relationship, the first data and the second data are converted to a first reference coordinate system, which is determined from second coordinate systems of optical tracking systems at different positions, and the optical tracking system at each position has a corresponding second coordinate system.

6. The device calibration method according to claim 1, characterized in that: The step of obtaining a first coordinate set obtained by measuring a calibration plate at different positions using a laser tracker includes: Acquire a first sub-coordinate set obtained by each of a plurality of laser trackers measuring the calibration plate at different positions, where the different positions are within a common field of view of the plurality of laser trackers and the optical tracking system; Determining a first relative position relationship between first coordinate systems corresponding to the plurality of laser trackers based on the first sub-coordinate set corresponding to each laser tracker; Based on the first relative position relationship, converting the first sub-coordinate set corresponding to each laser tracker into a second reference coordinate system to determine the first coordinate set; wherein the second reference coordinate system is determined from the first coordinate systems corresponding to the multiple laser trackers; Accordingly, 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 includes: A first target transformation relationship between the second reference coordinate system and the second coordinate system is determined based on the first coordinate set and the second coordinate set.

7. The device calibration method according to claim 1, characterized in that: The acquiring of a second coordinate set obtained by measuring the calibration plate at different positions by the optical tracking system comprises: Acquire a second sub-coordinate set obtained by measuring the calibration plate at a different position by each of the plurality of optical tracking systems, wherein the different positions are within a common field of view of the plurality of trackers and the laser tracker; Determining a second relative position relationship between the second coordinate systems corresponding to each optical tracking system based on the second sub-coordinate set corresponding to each optical tracking system; Based on the second relative position relationship, convert the second sub-coordinate set corresponding to each optical tracking system into a 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 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 includes: A first target transformation relationship between the third reference coordinate system and the first coordinate system is determined based on the first coordinate set and the second coordinate set.

8. A device calibration system, characterized in that: include: A laser tracker is used to measure the calibration plate at different positions to obtain a first coordinate set; an optical tracking system, configured to measure the calibration plate at different positions to obtain a second coordinate set, and to obtain a target point coordinate set obtained by measuring the target point of the optical tracking system with the laser tracker; 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 conversion relationship between the second coordinate system and the target point based on the first target conversion relationship and the target point coordinate set; The electronic device is further used to complete the calibration of the optical tracking system based on the second target conversion relationship.

9. An electronic device, characterized in that: The electronic device includes a processor and a memory, and the processor is used to execute a computer program stored in the memory to implement the device calibration method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium stores at least one instruction, and when the at least one instruction is executed by a processor, the device calibration method according to any one of claims 1 to 7 is implemented.

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