Method, device and system for calibrating the relative position of a height measuring device and an imaging device

Abstract

The embodiment of the application discloses a kind of relative position calibration method, device and system of height measuring device and imaging device, according to the height measuring result obtained according to the relative movement of height measuring device and calibration plate along at least two directions, respectively determine the planar coordinates of at least two points on each edge in at least two edges on calibration plate;According to the planar coordinates of at least two points on each edge in at least two edges on calibration plate, determine the boundary equation corresponding to at least two edges respectively;According to the boundary equation corresponding to at least two edges respectively, determine the first planar coordinates of at least one intersection point of at least two edges;The second planar coordinates of at least one intersection point are grabbed by imaging device;According to the first planar coordinates and the second planar coordinates corresponding to at least one same intersection point, determine the relative position of height measuring device and imaging device, to carry out relative position calibration to height measuring device and imaging device, guarantee the accuracy of product space coordinates subsequently acquired.

Description

Technical Field

[0001] This invention relates to the field of display technology, and in particular to a method, apparatus, and system for calibrating the relative position of a height measuring device and an imaging device. Background Technology

[0002] Height measuring devices and imaging devices are widely used in industrial equipment.

[0003] When the equipment includes both a height measuring device and an imaging device, the imaging device can capture the coordinates of the product's edge position, and these edge position coordinates need to be converted to a spatial coordinate system.

[0004] However, the spatial coordinate system is calibrated based on the height measurement results of the altimeter. Therefore, it is necessary to calibrate the relative positions of the imaging device and the altimeter to ensure the accuracy of the spatial coordinates of the obtained product. Summary of the Invention

[0005] This invention provides a method, apparatus, and system for calibrating the relative position of an altitude measuring device and an imaging device, thereby ensuring the accuracy of the spatial coordinates of the obtained product.

[0006] According to one aspect of the present invention, a method for calibrating the relative position of a height measuring device and an imaging device is provided, comprising: Based on the height measurement results obtained by the relative movement of the height measuring device and the calibration plate in at least two directions, determine the plane coordinates of at least two points on each of the at least two edges of the calibration plate. Determine the boundary equations corresponding to the at least two edges based on the planar coordinates of at least two points on each of the at least two edges on the calibration plate. Determine the first plane coordinates of at least one intersection point of at least two edges based on the boundary equations corresponding to at least two edges respectively; The imaging device captures the second plane coordinates of at least one intersection point; The relative positions of the altimeter and the imaging device are determined based on the first and second plane coordinates corresponding to at least one identical intersection point.

[0007] Optionally, based on the height measurement results obtained from the relative movement of the height measuring device and the calibration plate in at least two directions, the planar coordinates of at least two points on each of the at least two edges of the calibration plate are determined, including: The plane coordinates of the points on the edge are determined based on the coordinates of the changes in the height measurement results when the height measuring device moves relative to the calibration plate.

[0008] Optionally, based on the height measurement results obtained from the relative movement of the height measuring device and the calibration plate in at least two directions, the planar coordinates of at least two points on each of the at least two edges of the calibration plate are determined, including: When the height measuring device and the calibration plate move relative to each other in each direction, the relative speed of the height measuring device and the calibration plate is controlled to change from fast to slow, and the height measurement result of the height measuring device is obtained.

[0009] Optionally, based on the planar coordinates of at least two points on each of the at least two edges of the calibration plate, determine the boundary equations corresponding to the at least two edges, including: Based on the relative movement of the height measuring device and the calibration plate along the first direction, the planar coordinates of at least two points on the first edge of the calibration plate are obtained, and the first boundary equation of the first edge is determined; the extension direction of the first edge intersects with the first direction. Based on the relative movement of the height measuring device and the calibration plate along the second direction, the plane coordinates of at least two points on the second edge of the calibration plate are obtained, and the second boundary equation of the second edge is determined; the extension direction of the second edge intersects with the second direction, the extension direction of the second edge intersects with the extension direction of the first edge, and the second direction intersects with the first direction. Determine the first plane coordinates of at least one intersection point of at least two edges based on the boundary equations corresponding to at least two edges, including: Based on the first boundary equation and the second boundary equation, determine the first plane coordinates of the first intersection point of the first edge and the second edge. Determining the relative positions of the height measuring device and the imaging device based on the first and second plane coordinates corresponding to at least one identical intersection point includes: The relative positions of the height measuring device and the imaging device are determined based on the first plane coordinates and the second plane coordinates of the first intersection point.

[0010] Optionally, the relative positions of the height measuring device and the imaging device are determined based on the first plane coordinates and the second plane coordinates of the first intersection point, including: The first relative coordinate in the relative position is determined based on the difference between the first plane coordinates and the first coordinate values ​​in the second plane coordinates of the first intersection point; The second relative coordinate in the relative position is determined by the difference between the first plane coordinates of the first intersection point and the second coordinate value in the second plane coordinates.

[0011] Optionally, based on the planar coordinates of at least two points on each of the at least two edges of the calibration plate, the boundary equations corresponding to the at least two edges are determined, further including: Based on the relative movement of the height measuring device and the calibration plate along the third direction, the plane coordinates of at least two points on the third edge of the calibration plate are obtained, and the third boundary equation of the third edge is determined; the extension direction of the third edge intersects with the third direction; and the extension direction of the third edge intersects with the extension direction of the second edge. Determining the first plane coordinates of at least one intersection point of at least two edges based on the boundary equations corresponding to at least two edges, further includes: Based on the second boundary equation and the third boundary equation, determine the first plane coordinates of the second intersection point of the second edge and the third edge; Based on the first plane coordinates and the second plane coordinates of the first intersection point, determine the relative positions of the height measuring device and the imaging device, including: The relative positions of the height measuring device and the imaging device are determined based on the first and second plane coordinates of the first intersection point, and the first and second plane coordinates of the second intersection point.

[0012] Optionally, the relative positions of the height measuring device and the imaging device are determined based on the first and second plane coordinates of the first intersection point, and the first and second plane coordinates of the second intersection point, including: Based on the difference between the first plane coordinates and the first coordinates in the second plane coordinates of the first intersection point, and the difference between the first plane coordinates and the first coordinates in the second plane coordinates of the second intersection point, determine the first relative coordinates in the relative positions; The second relative coordinates in the relative positions are determined based on the difference between the first plane coordinates and the second coordinates in the second plane coordinates of the first intersection point, and the difference between the first plane coordinates and the second coordinates in the second plane coordinates of the second intersection point.

[0013] Optionally, the calibration plate is polygonal.

[0014] According to another aspect of the present invention, a relative position calibration device for a height measuring device and an imaging device is provided, comprising: The edge point coordinate determination module is used to determine the plane coordinates of at least two points on each of the at least two edges of the calibration plate based on the height measurement results obtained by the relative movement of the height measuring device and the calibration plate in at least two directions. The boundary equation determination module is used to determine the boundary equations corresponding to at least two edges based on the planar coordinates of at least two points on each edge of the calibration plate. The intersection point coordinate determination module is used to determine the first plane coordinates of at least one intersection point of at least two edges based on the boundary equations corresponding to at least two edges respectively. A grasping module is used to grasp the second plane coordinates of at least one intersection point through an imaging device; The relative position determination module is used to determine the relative position of the height measuring device and the imaging device based on the first plane coordinates and the second plane coordinates corresponding to at least one identical intersection point.

[0015] According to another aspect of the present invention, a relative position calibration system for a height measuring device and an imaging device is provided, comprising: a height measuring device, an imaging device, a machine base, and a processing module; the machine base includes a platform and a column; the platform is used to support a calibration plate; The processing module is electrically connected to the height measuring device and the imaging device, which are fixed to the column. The processing module is used to determine the plane coordinates of at least two points on each of the at least two edges of the calibration plate based on the height measurement results obtained by the relative movement of the height measuring device and the calibration plate in at least two directions; to determine the boundary equations corresponding to the at least two edges based on the plane coordinates of the at least two points on each of the at least two edges of the calibration plate; to determine the first plane coordinates of at least one intersection point of the at least two edges based on the boundary equations corresponding to the at least two edges; to capture the second plane coordinates of at least one intersection point through the imaging device; and to determine the relative position of the height measuring device and the imaging device based on the first and second plane coordinates corresponding to at least one identical intersection point.

[0016] The method, apparatus, and system for calibrating the relative position of a height measuring device and an imaging device according to embodiments of the present invention determine the planar coordinates of at least two points on each of at least two edges of the calibration plate based on the height measurement results obtained by the relative movement of the height measuring device and the calibration plate along at least two directions; determine the boundary equations corresponding to the at least two edges based on the planar coordinates of the at least two points on each of the at least two edges of the calibration plate; determine the first planar coordinates of at least one intersection point of the at least two edges based on the boundary equations corresponding to the at least two edges; capture the second planar coordinates of at least one intersection point using the imaging device; and determine the relative position of the height measuring device and the imaging device based on the first and second planar coordinates corresponding to at least one identical intersection point. The technical solution of the embodiments of the present invention, by obtaining the coordinate difference corresponding to the same intersection point from the first planar coordinates obtained from the height measurement results and the second planar coordinates captured by the imaging device based on the intersection point of the calibration plate's edges, calibrates the relative position of the height measuring device and the imaging device, thereby ensuring the accuracy of the subsequently acquired product spatial coordinates.

[0017] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a flowchart of a method for calibrating the relative position of a height measuring device and an imaging device according to an embodiment of the present invention; Figure 2 This is a schematic diagram in a plane coordinate system after the calibration plate is placed on the stage plane; Figure 3 This is a flowchart of another method for calibrating the relative position of a height measuring device and an imaging device provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the imaging device capturing the first intersection point; Figure 5 This is a flowchart of another method for calibrating the relative position of a height measuring device and an imaging device provided in an embodiment of the present invention; Figure 6 This is a schematic diagram of the imaging device capturing the second intersection point; Figure 7 This is a schematic diagram of the structure of a relative position calibration device for a height measuring device and an imaging device provided in an embodiment of the present invention; Figure 8 This is a schematic diagram of the relative position calibration system of a height measuring device and an imaging device provided in an embodiment of the present invention. Detailed Implementation

[0020] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0021] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0022] Figure 1 This is a flowchart illustrating a method for calibrating the relative position of a height measuring device and an imaging device according to an embodiment of the present invention. This method can be executed by a relative position calibration device for the height measuring device and the imaging device. This device can be implemented in software and / or hardware and can be configured in an electronic device. Optionally, the height measuring device includes a laser altimeter, and the imaging device includes a camera. Exemplarily, the relative position calibration method for the height measuring device and the imaging device can be used in dispensing equipment or inkjet equipment, and can also be used in other devices that simultaneously include a height measuring device and an imaging device. (Reference) Figure 1 The method for calibrating the relative position of the height measuring device and the imaging device includes: S110. Based on the height measurement results obtained by the relative movement of the height measuring device and the calibration plate in at least two directions, determine the plane coordinates of at least two points on each of the at least two edges of the calibration plate.

[0023] Specifically, place the calibration plate on the stage plane and fix the calibration plate. Figure 2 This is a schematic diagram in a planar coordinate system showing the calibration plate placed on the platform plane. For example, screws are used to lock the apex of the calibration plate to prevent displacement during calibration, which could affect the final calibration accuracy. Optionally, the initial position of the height measuring device is adjusted before relative movement between the height measuring device and the calibration plate. For example, in the initial position, the orthographic projection of the height measuring device onto the plane of the calibration plate lies within the calibration plate, and / or the laser emitted by the height measuring device can illuminate the calibration plate. In some embodiments, the height measured by the height measuring device in the initial position is 0.

[0024] In this step, the height measuring device and the calibration plate are moved relative to each other. Since the calibration plate is fixed on the platform, the relative movement between the height measuring device and the calibration plate can be achieved by controlling the movement of the height measuring device; and / or, the relative movement between the height measuring device and the calibration plate can be achieved by controlling the movement of the platform. During the relative movement between the height measuring device and the calibration plate, the relative position between the height measuring device and the imaging device remains unchanged. For example, the height measuring device and the imaging device can be fixed on the same column, and the height measuring device can be moved by driving the column. During the relative movement between the height measuring device and the calibration plate, height can be measured in real time, obtaining height measurement results at multiple positions on the calibration plate.

[0025] Using the calibration plate as Figure 2 Taking the rectangle shown as an example, by moving the height measuring device and the calibration plate relative to each other along the first coordinate axis x, the first point A1 and the second point A2 on the width edge can be calibrated. For example, firstly, the height measuring device is adjusted so that its orthographic projection is inside the calibration plate, and its coordinate on the second coordinate axis y is Ya1. Then, the height measuring device and the calibration plate are moved along the first coordinate axis x, and the height measurement results are obtained in real time to determine the coordinates Xa1 of the first point A1 on the first coordinate axis x, thus obtaining the coordinates (Xa1, Ya1) of the first point A1. Next, the height measuring device is adjusted so that its orthographic projection is inside the calibration plate, and its coordinate on the second coordinate axis y is Ya2. Then, the height measuring device and the calibration plate are moved along the first coordinate axis x, and the height measurement results are obtained in real time to determine the coordinates Xa2 of the second point A2 on the first coordinate axis x, thus obtaining the coordinates (Xa2, Ya2) of the second point A2. By moving the height measuring device and the calibration plate relative to each other along the second coordinate axis y, the third point B1 and the fourth point B2 on the length edge can be calibrated. For example, firstly, the height measuring device is adjusted so that its orthographic projection is inside the calibration plate, and its coordinate on the first coordinate axis x is Xb1. Then, the height measuring device and the calibration plate are controlled to move along the second coordinate axis y, and the height measurement results are acquired in real time to determine the coordinates Yb1 of the third point B1 on the second coordinate axis y, thus obtaining the coordinates (Xb1, Yb1) of the third point B1. Next, the height measuring device is adjusted so that its orthographic projection is inside the calibration plate, and its coordinate on the first coordinate axis x is Xb2. Then, the height measuring device and the calibration plate are controlled to move along the second coordinate axis y, and the height measurement results are acquired in real time to determine the coordinates Yb2 of the second point A2 on the second coordinate axis y, thus obtaining the coordinates (Xb2, Yb2) of the fourth point B2.

[0026] S120. Based on the planar coordinates of at least two points on each of the at least two edges of the calibration plate, determine the boundary equations corresponding to the at least two edges respectively.

[0027] Specifically, when the edge of the calibration plate is a straight line, the equation of the straight line can be determined based on the plane coordinates of two points on the edge, and this equation serves as the boundary equation for the edge. When the edge of the calibration plate is a curve, the equation of the curve can be determined based on the plane coordinates of at least three points on the edge, and this curve equation serves as the boundary equation for the edge.

[0028] S130. Determine the first plane coordinates of at least one intersection point of at least two edges based on the boundary equations corresponding to at least two edges respectively.

[0029] Specifically, for the two intersecting edges of the calibration plate, the first plane coordinates of the intersection point can be obtained by solving the boundary equations corresponding to the two edges respectively. For example, the first plane coordinates of the intersection point can be obtained by simultaneously solving the boundary equations corresponding to the two intersecting edges of the calibration plate. That is, the first plane coordinates are calculated based on the boundary equations.

[0030] S140. Capture the second plane coordinates of at least one intersection point using an imaging device.

[0031] Specifically, the second plane coordinates of the intersection point of the calibration board's edges are captured by the imaging device. This can be achieved using a capture method found in related technologies. For example, the second plane coordinates of the intersection point can be directly obtained using the vision-integrated edge capture and intersection point calculation operator formula. In other words, the second plane coordinates are captured by the imaging device.

[0032] S150. Determine the relative positions of the height measuring device and the imaging device based on the first plane coordinates and the second plane coordinates corresponding to at least one identical intersection point.

[0033] Specifically, the relative positions of the height measuring device and the imaging device are determined based on the first plane coordinates of the intersection point of the edges determined by the height measurement results and the second plane coordinates of the same intersection point captured by the imaging device. For example, when the relative positions of the height measuring device and the imaging device are determined based on the first plane coordinates and the second plane coordinates corresponding to the intersection point of two edges (i.e., one intersection point), the relative positions are determined based on the difference between the first plane coordinates and the second plane coordinates corresponding to that intersection point. When the relative positions of the height measuring device and the imaging device are determined based on the first plane coordinates and the second plane coordinates corresponding to at least two intersection points respectively, the relative positions can be determined based on the difference between the first plane coordinates and the second plane coordinates corresponding to each intersection point.

[0034] The relative position calibration method for the height measuring device and the imaging device in this embodiment involves determining the planar coordinates of at least two points on each of the at least two edges of the calibration plate based on the height measurement results obtained from the relative movement of the height measuring device and the calibration plate in at least two directions; determining the boundary equations corresponding to the at least two edges based on the planar coordinates of the at least two points on each of the at least two edges; determining the first planar coordinates of at least one intersection point of the at least two edges based on the boundary equations corresponding to the at least two edges; capturing the second planar coordinates of at least one intersection point using the imaging device; and determining the relative position of the height measuring device and the imaging device based on the first and second planar coordinates corresponding to at least one identical intersection point. This technical solution allows for the determination of the coordinate differences corresponding to the same intersection point by using the first planar coordinates obtained from the height measurement results and the second planar coordinates captured by the imaging device at the intersection point of the calibration plate's edges, thereby calibrating the relative position of the height measuring device and the imaging device and ensuring the accuracy of the subsequently acquired product spatial coordinates.

[0035] In some embodiments, S110 includes: determining the planar coordinates of a point on the edge based on the coordinates of the points where the height measurement result changes when the height measuring device moves relative to the calibration plate.

[0036] Specifically, during the relative movement of the height measuring device and the calibration plate, the height measuring device moves from having its orthographic projection within the calibration plate to having its orthographic projection outside the calibration plate, or vice versa. Because the calibration plate has a certain thickness, the height measurement result will change abruptly at the edge of the calibration plate. For example, if the initial position of the height measuring device is that its orthographic projection on the plane of the calibration plate is within the calibration plate, then during the relative movement of the height measuring device and the calibration plate, the height measuring device will first measure the height of the calibration plate, i.e., the thickness of the calibration plate, until the height measuring device crosses the edge of the calibration plate. At this point, the height measured by the height measuring device is the height of the platform plane, meaning the height measurement result will change abruptly. Based on this, the plane coordinates of points on the edge can be obtained from the coordinates of the points where the height measurement result changes abruptly. For example, the plane coordinates of the point corresponding to the previous height measurement result where the height measurement result changed abruptly can be used as the plane coordinates of the edge points of the calibration plate. The criterion for a sudden change in the height measurement result can be preset. For example, during the relative movement of the height measuring device and the calibration plate, if the absolute value of the difference between two consecutive height measurement results is greater than or equal to a preset threshold, the preset threshold can be set according to the thickness of the calibration plate. For example, the preset threshold is greater than or equal to half the thickness of the calibration plate and less than or equal to the thickness of the calibration plate.

[0037] Using the calibration plate as Figure 2Taking the rectangle shown as an example, by moving the height measuring device and the calibration plate relative to each other along the first coordinate axis x, the first point A1 on the width edge can be calibrated. For example, firstly, the height measuring device is adjusted so that its orthographic projection is inside the calibration plate, and its coordinate on the second coordinate axis is Ya1. Then, the height measuring device and the calibration plate are controlled to move along the first coordinate axis x, and the height measurement results are acquired in real time. When a sudden change occurs in the height measurement result, the previous height measurement result is determined as the coordinate Xa1 of the first point A1 on the first coordinate axis, thus obtaining the coordinates (Xa1, Ya1) of the first point A1. For example, during the relative movement of the height measuring device and the calibration plate along the first coordinate axis x, the acquired height measurement results are H0, H0, H0, H0, H0…H0, H1. The absolute value of the difference between H1 and H0 is greater than or equal to a set threshold. Then, the coordinate of the first coordinate axis where the previous height measurement result was H0 is used as the coordinate Xa1 of the first point A1 on the first coordinate axis. The method for determining the planar coordinates of the second point A2 on the width edge, and the method for determining the planar coordinates of the third point B1 and the fourth point B2 on the length edge, is the same as the method for determining the planar coordinates of the first point A1 on the width edge, and will not be repeated here.

[0038] In some embodiments, before S110, the method further includes: controlling the relative movement speed of the height measuring device and the calibration plate to change from fast to slow when the height measuring device and the calibration plate move relative to each other in each direction, and obtaining the height measurement result of the height measuring device.

[0039] Optionally, when the height measuring device and the calibration plate move relative to each other in a set direction, if the distance between the edge to be measured on the height measuring device and the calibration plate in the set direction is greater than or equal to a first preset distance, the relative movement speed of the height measuring device and the calibration plate can be controlled as a first speed. If the distance between the edge to be measured on the height measuring device and the calibration plate in the set direction is less than the first preset distance, the relative movement speed of the height measuring device and the calibration plate can be controlled as a second speed. The first speed is greater than the second speed. The first preset distance can be set according to actual conditions. It should be noted that during the relative movement of the height measuring device and the calibration plate, the first speed can remain constant or change; the second speed can also remain constant or change, as long as the first speed is greater than the second speed. This ensures that when the height measuring device approaches the edge of the calibration plate, the relative movement speed of the height measuring device and the calibration plate is relatively small, making the points where abrupt changes in the height measurement result more accurate, thereby improving the accuracy of the planar coordinates of the points on the edge of the calibration plate.

[0040] The set direction can be any direction in which the height measuring device and the calibration plate move relative to each other. The edge to be measured is the edge on the calibration plate that includes the plane coordinate point to be determined when the height measuring device and the calibration plate move along the set direction. Figure 2Taking the case shown as an example, when the height measuring device and the calibration plate move relative to each other along the length of the calibration plate, the edge to be measured is the edge along the width of the calibration plate.

[0041] Figure 3 This is a flowchart of another method for calibrating the relative position of a height measuring device and an imaging device according to an embodiment of the present invention, referred to in the following text. Figure 3 The method for calibrating the relative position of the height measuring device and the imaging device includes: S210. Based on the height measurement results obtained by the relative movement of the height measuring device and the calibration plate in at least two directions, determine the plane coordinates of at least two points on each of the at least two edges of the calibration plate.

[0042] Among them, at least two directions include a first direction and a second direction, and the first direction and the second direction intersect.

[0043] S220. Based on the plane coordinates of at least two points on the first edge of the calibration plate obtained by the relative movement of the height measuring device and the calibration plate along the first direction, determine the first boundary equation of the first edge; the extension direction of the first edge intersects with the first direction.

[0044] by Figure 2 Taking the case where the calibration plate is rectangular as an example, the first direction p1 is the length direction of the calibration plate, and correspondingly, the first edge 10 is the width edge of the calibration plate. For example, the first edge 10 is the right edge of the calibration plate. In this step, based on the movement of the height measuring device and the calibration plate along the first direction p1, the planar coordinates of at least two points on the first edge 10 of the calibration plate are obtained, such as the planar coordinates of the first point A1 and the second point A2 on the first edge 10. The method for determining the planar coordinates of the first point A1 and the second point A2 can refer to the above embodiment, and will not be repeated here. For example, the planar coordinates of the first point A1 are (Xa1, Ya1), and the planar coordinates of the second point A2 are (Xa2, Ya2). Based on the planar coordinates of the first point A1 and the second point A2, the boundary equation of the first edge 10 can be determined.

[0045] Specifically, based on the plane coordinates (Xa1, Ya1) of the first point A1 and the plane coordinates (Xa2, Ya2) of the second point A2 on the first edge 10, the slope K1 of the straight line of the first edge 10 can be determined. That is: K1 = (Ya2 - Ya1) / (Xa2 - Xa1). The equation of the straight line of the first edge 10, that is, the equation of the first boundary, is: Y - Ya1 = K1(X - Xa1), which is: (Ya2 - Ya1)X - (Xa2 - Xa1)Y + (Xa2 * Ya1 - Xa1 * Ya2) = 0.

[0046] S230. Based on the relative movement of the height measuring device and the calibration plate along the second direction, obtain the plane coordinates of at least two points on the second edge of the calibration plate, and determine the second boundary equation of the second edge.

[0047] The extension direction of the second edge intersects with the second direction, and the extension direction of the second edge intersects with the extension direction of the first edge.

[0048] by Figure 2 Taking the case where the calibration plate is rectangular as an example, the second direction p2 is the width direction of the calibration plate, and correspondingly, the second edge 20 is the length edge of the calibration plate. For example, the first edge 10 is the top edge of the calibration plate. In this step, based on the movement of the height measuring device and the calibration plate along the second direction p2, the planar coordinates of at least two points on the second edge 20 of the calibration plate are obtained. For example, the planar coordinates of the third point B1 and the fourth point B2 on the second edge 20. The method for determining the planar coordinates of the third point B1 and the fourth point B2 can refer to the above embodiment and will not be repeated here. For example, the planar coordinates of the third point B1 are (Xb1, Yb1), and the planar coordinates of the second point A2 are (Xb2, Yb2). Based on the plane coordinates of the third point B1 and the fourth point B2, the equation of the straight line of the second edge 20 can be determined, that is, the equation of the second boundary is (Yb2-Yb1)X-(Xb2-Xb1)Y+(Xb2*Yb1-Xb1*Yb2)=0.

[0049] S240. Based on the first boundary equation and the second boundary equation, determine the first plane coordinates of the first intersection point of the first edge and the second edge.

[0050] Specifically, by combining the first boundary equation and the second boundary equation, we can obtain the first plane coordinates (Xm, Ym) of the intersection point of the first edge 10 and the second edge 20, which is the first intersection point M. Here, Xm=(B1*C2-B2*C1) / (A1*B2-A2*B1), Ym=(A2*C1-A1*C2) / (A1*B2-A2*B1), A1=Ya2-Ya1, B1=Xa2-Xa1, C1=Xa2*Ya1-Xa1*Ya2.

[0051] Substitute A1, B1, and C1 into Xm and Ym: Xm=((Xa2-Xa1)*(Xb2*Yb1-Xb1*Yb2)-(Xb2-Xb1)*(Xa2*Ya1-Xa1*Ya2)) / ((Ya2-Ya1)*(Xb2-Xb1)-(Yb2-Yb1)*(Xa2-Xa1)); Ym=((Yb2-Yb1)*(Xa2*Ya1-Xa1*Ya2)-(Ya2-Ya1)*(Xb2*Yb1-Xb1*Yb2)) / ((Ya2-Ya1)*(Xb2-Xb1)-(Yb2-Yb1)*(Xa2-Xa1)).

[0052] S250, The second plane coordinates of the first intersection point are captured by the imaging device.

[0053] Figure 4 This is a schematic diagram of the imaging device capturing the first intersection point, as shown below. Figure 4 As shown, for example, in the image captured by the imaging device, the first intersection point is denoted as N, and the corresponding second plane coordinates are denoted as (Xn, Yn).

[0054] S260. Determine the relative positions of the height measuring device and the imaging device based on the first plane coordinates and the second plane coordinates of the first intersection point.

[0055] Specifically, in this step, the relative positions of the height measuring device and the imaging device can be determined based on the difference between the first plane coordinates and the second plane coordinates corresponding to the first intersection point, thereby calibrating their relative positions.

[0056] In some embodiments, S240 includes: determining a first relative coordinate in the relative position based on the difference between the first plane coordinates of the first intersection point and the first coordinate value in the second plane coordinates; and determining a second relative coordinate in the relative position based on the difference between the first plane coordinates of the first intersection point and the second coordinate value in the second plane coordinates. Wherein, the difference between the first plane coordinates of the first intersection point and the first coordinate value in the second plane coordinates is ΔX1 = Xn - Xm, and the difference between the first plane coordinates of the first intersection point and the second coordinate value in the second plane coordinates is ΔY1 = Yn - Ym. In some embodiments, (ΔX1, ΔY1) is defined as the relative position of the height measuring device and the imaging device.

[0057] Figure 5 This is a flowchart of another method for calibrating the relative position of a height measuring device and an imaging device according to an embodiment of the present invention, referred to in the following text. Figure 5 The method for calibrating the relative position of the height measuring device and the imaging device includes: S310. Based on the height measurement results obtained by the relative movement of the height measuring device and the calibration plate in at least two directions, determine the plane coordinates of at least two points on each of the at least two edges of the calibration plate.

[0058] Among them, at least two directions include a first direction and a second direction, and the first direction and the second direction intersect.

[0059] S320. Based on the plane coordinates of at least two points on the first edge of the calibration plate obtained by the relative movement of the height measuring device and the calibration plate along the first direction, determine the first boundary equation of the first edge; the extension direction of the first edge intersects with the first direction.

[0060] Referring to the above embodiment, the first boundary equation is: (Ya2-Ya1)X-(Xa2-Xa1)Y+(Xa2*Ya1-Xa1*Ya2)=0.

[0061] S330. Based on the relative movement of the height measuring device and the calibration plate along the second direction, obtain the plane coordinates of at least two points on the second edge of the calibration plate, and determine the second boundary equation of the second edge.

[0062] Referring to the above embodiment, the second boundary equation is: (Yb2-Yb1)X-(Xb2-Xb1)Y+(Xb2*Yb1-Xb1*Yb2)=0.

[0063] S340. Based on the plane coordinates of at least two points on the third edge of the calibration plate obtained by the relative movement of the height measuring device and the calibration plate along the third direction, determine the third boundary equation of the third edge.

[0064] like Figure 2 As shown, the extension direction of the third edge 30 is parallel to the third direction ( Figure 2 (Not shown in the diagram) intersects; and the extension direction of the third edge 30 intersects the extension direction of the second edge 20. When the calibration plate is rectangular, the third edge 30 is parallel to the first edge 10, and correspondingly, the extension direction of the third edge 30 is the same as the extension direction of the first edge 10. Both the third direction and the first direction p1 are parallel to the extension direction of the length edge of the calibration plate. Both the third direction and the first direction p1 can be the extension direction of the length edge of the calibration plate (e.g., the second edge 20).

[0065] The two points on the third edge 30, denoted as the fifth point C1 and the sixth point C2, have plane coordinates of (Xc1, Yc1) and (Xc2, Yc2) respectively. Then the equation of the line corresponding to the third edge 30, that is, the equation of the third boundary, is (Yc2-Yc1)X-(Xc2-Xc1)Y+(Xc2*Yc1-Xc1*Yc2)=0.

[0066] S350. Based on the first boundary equation and the second boundary equation, determine the first plane coordinates of the first intersection point of the first edge and the second edge.

[0067] Referring to the above embodiment, the first plane coordinates of the first intersection point M are (Xm, Ym).

[0068] S360. Based on the second boundary equation and the third boundary equation, determine the first plane coordinates of the second intersection point of the second edge and the third edge.

[0069] Specifically, by simultaneously solving the second and third boundary equations, we can obtain the intersection point of the second and third edges, which is also the second plane coordinate (Xw, Yw) of the second intersection point W. Xw=((Xb2-Xb1)*(Xc2*Yc1-Xc1*Yc2)-(Xc2-Xc1)*(Xb2*Yb1-Xb1*Yb2)) / ((Yb2-Yb1)*(Xc2-Xc1)-(Yc2-Yc1)*(Xb2-Xb1)); Yw=((Yc2-Yc1)*(Xb2*Yb1-Xb1*Yb2)-(Yb2-Yb1)*(Xc2*Yc1-Xc1*Yc2)) / ((Yb2-Yb1)*(Xc2-Xc1)-(Yc2-Yc1)*(Xb2-Xb1)).

[0070] S370, The second plane coordinates of the first intersection point and the second intersection point are captured by the imaging device.

[0071] like Figure 4 As shown, for example, in the image captured by the imaging device, the first intersection point is denoted as N, and the corresponding second plane coordinates are denoted as (Xn, Yn). Figure 6 This is a schematic diagram of the imaging device capturing the second intersection point, as shown below. Figure 6 As shown, for example, in the image captured by the imaging device, the first intersection point is denoted as V, and the corresponding second plane coordinates are denoted as (Xv, Yv).

[0072] S380. Determine the relative positions of the height measuring device and the imaging device based on the first plane coordinates and the second plane coordinates of the first intersection point, and the first plane coordinates and the second plane coordinates of the second intersection point.

[0073] Specifically, in this step, the relative positions of the height measuring device and the imaging device can be determined based on the difference between the first plane coordinates and the second plane coordinates corresponding to the first intersection point, as well as the difference between the first plane coordinates and the second plane coordinates corresponding to the second intersection point, thereby calibrating their relative positions.

[0074] In some embodiments, S380 includes: determining a first relative coordinate in the relative position based on the difference between the first plane coordinates of the first intersection point and the first coordinate value in the second plane coordinates, and the difference between the first plane coordinates of the second intersection point and the first coordinate value in the second plane coordinates; and determining a second relative coordinate in the relative position based on the difference between the first plane coordinates of the first intersection point and the second coordinate value in the second plane coordinates, and the difference between the first plane coordinates of the second intersection point and the second coordinate value in the second plane coordinates.

[0075] The differences ΔX1, ΔY1, ΔX2, and ΔY2 between the first and second plane coordinates of the first intersection point, respectively, can be calculated using the following formulas: △X1=(Xn-Xm)=(Xn-((Xa2-Xa1)*(Xb2*Yb1-Xb1*Yb2)-(Xb2-Xb1)*(Xa2*Ya1-Xa1*Ya2)) / ((Ya2-Ya1)*(Xb2-Xb1)-(Yb2-Yb1)*(Xa2-Xa1))); △Y1=(Yn-Ym)=(Yn-((Yb2-Yb1)*(Xa2*Ya1-Xa1*Ya2)-(Ya2-Ya1)*(Xb2*Yb1-Xb1*Yb2)) / ((Ya2-Ya1)*(Xb2-Xb1)-(Yb2-Yb1)*(Xa2-Xa1))); △X2=(Xv-Xw)=(Xv-((Xc2-Xc1)*(Xb2*Yb1-Xb1*Yb2)-(Xb2-Xb1)*(Xc2*Yc1-Xc1*Yc2)) / ((Yc2-Yc1)*(Xb2-Xb1)-(Yb2-Yb1)*(Xc2-Xc1))); △Y2=(Yv-Yw)=(Yn-((Yb2-Yb1)*(Xc2*Yc1-Xc1*Yc2)-(Yc2-Yc1)*(Xb2*Yb1-Xb1*Yb2)) / ((Yc2-Yc1)*(Xb2-Xb1)-(Yb2-Yb1)*(Xc2-Xc1))).

[0076] In some embodiments, the difference between the first plane coordinates and the first coordinate value in the second plane coordinates of the first intersection point, and the average of the differences between the first plane coordinates and the first coordinate value in the second plane coordinates of the second intersection point, are determined as the first relative coordinates in the relative position; the difference between the first plane coordinates and the second coordinate value in the second plane coordinates of the first intersection point, and the average of the differences between the first plane coordinates and the second coordinate value in the second plane coordinates of the second intersection point, are determined as the second relative coordinates in the relative position. That is: the first relative coordinate △X = (△X1 + △X2) / 2, and the second relative coordinate △Y = (△Y1 + △Y2) / 2.

[0077] In other embodiments, the absolute value of the difference between the first plane coordinates and the first coordinate value in the second plane coordinates of the first intersection point, and the average of the absolute values ​​of the differences between the first plane coordinates and the first coordinate values ​​in the second plane coordinates of the second intersection point, are determined as the first relative coordinates in the relative positions; the absolute value of the difference between the first plane coordinates and the second coordinate value in the second plane coordinates of the first intersection point, and the average of the absolute values ​​of the differences between the first plane coordinates and the second coordinate values ​​in the second plane coordinates of the second intersection point, are determined as the second relative coordinates in the relative positions. That is: the first relative coordinate △X = (∣△X1∣ + ∣△X2∣) / 2, and the second relative coordinate △Y = (∣△Y1∣ + ∣△Y2∣) / 2.

[0078] Specifically, when the calibration plate is not placed flat on the stage, using only the position of a single vertex to calibrate the relative positions of the height measuring device and the imaging device can easily lead to calibration errors. In this embodiment, by calibrating the relative positions of the height measuring device and the imaging device based on the difference between the first and second plane coordinates of the first intersection point, and the difference between the first and second plane coordinates of the second intersection point, the error caused by using a single vertex on the calibration plate to calibrate the relative positions of the height measuring device and the imaging device when the calibration plate is not placed flat on the stage can be reduced, ensuring the accuracy of calibrating the relative positions of the height measuring device and the imaging device when the calibration plate is not placed flat.

[0079] In other embodiments, the height measurement results obtained by the height measuring device can be used to determine the first plane coordinates of more edge intersection points, and the imaging device can capture the second plane coordinates of the corresponding edge intersection points. Then, the relative position of the height measuring device and the imaging device can be calibrated based on the difference between the first plane coordinates and the second plane coordinates of more edge intersection points. That is, the relative position of the height measuring device and the imaging device can be calibrated based on the difference between the first plane coordinates and the second plane coordinates of more vertices of the calibration plate, thereby further improving the calibration accuracy.

[0080] Optionally, the calibration plate is polygonal. In some embodiments, the calibration plate has the following shape: Figure 2 The above embodiments of the present invention are all illustrated using the case where the calibration plate is rectangular. In other optional embodiments, the edge of the calibration plate may be curved. In this case, the curve equation of the edge can be determined based on at least three points on the edge of the calibration plate as the boundary equation of the edge.

[0081] This invention also provides a device for calibrating the relative position of a height measuring device and an imaging device. Figure 7 This is a schematic diagram of the structure of a relative position calibration device for a height measuring device and an imaging device provided in an embodiment of the present invention. (Refer to...) Figure 7 The relative position calibration device between the height measuring device and the imaging device includes: The edge point coordinate determination module 410 is used to determine the plane coordinates of at least two points on each of the at least two edges of the calibration plate based on the height measurement results obtained by the relative movement of the height measuring device and the calibration plate in at least two directions. Boundary equation determination module 420 is used to determine the boundary equations corresponding to at least two edges based on the planar coordinates of at least two points on each of the at least two edges on the calibration plate. The intersection point coordinate determination module 430 is used to determine the first plane coordinates of at least one intersection point of at least two edges based on the boundary equations corresponding to at least two edges respectively. The grasping module 440 is used to grasp the second plane coordinates of at least one intersection point through the imaging device; The relative position determination module 450 is used to determine the relative position of the height measuring device and the imaging device based on the first plane coordinates and the second plane coordinates corresponding to at least one identical intersection point.

[0082] The relative position calibration device for the height measuring device and the imaging device in this embodiment can execute the relative position calibration method for the height measuring device and the imaging device provided in any embodiment of the present invention, and has the corresponding functional modules and beneficial effects of the method.

[0083] This invention also provides a system for calibrating the relative position of a height measuring device and an imaging device. Figure 8 This is a schematic diagram of the relative position calibration system of a height measuring device and an imaging device provided in an embodiment of the present invention. (Refer to...) Figure 8 The calibration system includes: a height measuring device 1, an imaging device 2, a machine base, and a processing module. Figure 8 (Not shown in the image). The machine includes a platform 3 and a column 4. The platform 3 is used to support the calibration plate 5. The processing module is electrically connected to the height measuring device 1 and the imaging device 2, respectively. The height measuring device 1 and the imaging device 2 are fixed on the column 4. The processing module is used to determine the plane coordinates of at least two points on each of the at least two edges of the calibration plate 5 based on the height measurement results obtained by the relative movement of the height measuring device 1 and the calibration plate 5 in at least two directions. Based on the plane coordinates of the at least two points on each of the at least two edges of the calibration plate 5, the processing module determines the boundary equations corresponding to the at least two edges. Based on the boundary equations corresponding to the at least two edges, the processing module determines the first plane coordinates of at least one intersection point of the at least two edges. The processing module captures the second plane coordinates of at least one intersection point through the imaging device 2. Based on the first plane coordinates and the second plane coordinates corresponding to at least one identical intersection point, the processing module determines the relative position of the height measuring device 1 and the imaging device 2.

[0084] The relative position calibration system of the height measuring device and the imaging device in this embodiment can be calibrated using the relative position calibration method of the height measuring device and the imaging device in any of the above embodiments of the present invention. It has the beneficial effects of the relative position calibration method of the height measuring device and the imaging device in any of the above embodiments of the present invention, and will not be described again here.

[0085] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0086] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A method for calibrating the relative position of a height measuring device and an imaging device, characterized in that, include: Based on the height measurement results obtained by the relative movement of the height measuring device and the calibration plate in at least two directions, the planar coordinates of at least two points on each of the at least two edges of the calibration plate are determined respectively. Based on the planar coordinates of at least two points on each of the at least two edges of the calibration plate, determine the boundary equations corresponding to the at least two edges respectively. Determine the first plane coordinates of at least one intersection point of at least two of the edges based on the boundary equations corresponding to the at least two edges respectively; The imaging device captures the second plane coordinates of at least one of the intersection points; The relative positions of the height measuring device and the imaging device are determined based on the first plane coordinates and the second plane coordinates corresponding to at least one identical intersection point.

2. The method for calibrating the relative position of the height measuring device and the imaging device according to claim 1, characterized in that, The step of determining the planar coordinates of at least two points on each of at least two edges of the calibration plate, based on the height measurement results obtained from the relative movement of the height measuring device and the calibration plate in at least two directions, includes: The planar coordinates of the points on the edge are determined based on the coordinates of the changes in the height measurement result when the height measuring device moves relative to the calibration plate.

3. The method for calibrating the relative position of the height measuring device and the imaging device according to claim 1 or 2, characterized in that, Based on the height measurement results obtained from the relative movement of the height measuring device and the calibration plate in at least two directions, determining the planar coordinates of at least two points on each of the at least two edges of the calibration plate includes: When the height measuring device and the calibration plate move relative to each other in each direction, the relative moving speed of the height measuring device and the calibration plate is controlled to change from fast to slow, and the height measuring result of the height measuring device is obtained.

4. The method for calibrating the relative position of the height measuring device and the imaging device according to claim 1 or 2, characterized in that, The step of determining the boundary equations corresponding to at least two edges based on the planar coordinates of at least two points on each of the at least two edges on the calibration plate includes: Based on the relative movement of the height measuring device and the calibration plate along the first direction, the planar coordinates of at least two points on the first edge of the calibration plate are obtained, and the first boundary equation of the first edge is determined; the extension direction of the first edge intersects the first direction. Based on the relative movement of the height measuring device and the calibration plate along the second direction, the planar coordinates of at least two points on the second edge of the calibration plate are obtained, and the second boundary equation of the second edge is determined; the extension direction of the second edge intersects with the second direction, the extension direction of the second edge intersects with the extension direction of the first edge, and the second direction intersects with the first direction. The step of determining the first plane coordinates of at least one intersection point of at least two of the edges based on the boundary equations corresponding to at least two of the edges includes: Based on the first boundary equation and the second boundary equation, determine the first plane coordinates of the first intersection point of the first edge and the second edge; Determining the relative position of the height measuring device and the imaging device based on the first plane coordinates and the second plane coordinates corresponding to at least one identical intersection point includes: The relative positions of the height measuring device and the imaging device are determined based on the first plane coordinates and the second plane coordinates of the first intersection point.

5. The method for calibrating the relative position of the height measuring device and the imaging device according to claim 4, characterized in that, Determining the relative position of the height measuring device and the imaging device based on the first plane coordinates and the second plane coordinates of the first intersection point includes: The first relative coordinate in the relative position is determined based on the difference between the first plane coordinates and the first coordinates in the second plane coordinates of the first intersection point; The second relative coordinate in the relative position is determined based on the difference between the first plane coordinates and the second coordinates in the second plane coordinates of the first intersection point.

6. The method for calibrating the relative position of the height measuring device and the imaging device according to claim 4, characterized in that, The step of determining the boundary equations corresponding to at least two edges based on the planar coordinates of at least two points on each of the at least two edges on the calibration plate further includes: The third boundary equation of the third edge is determined by obtaining the planar coordinates of at least two points on the third edge of the calibration plate based on the relative movement of the height measuring device and the calibration plate along a third direction; the extension direction of the third edge intersects the third direction; and the extension direction of the third edge intersects the extension direction of the second edge. The step of determining the first planar coordinates of at least one intersection point of at least two of the edges based on the boundary equations corresponding to at least two of the edges further includes: Based on the second boundary equation and the third boundary equation, determine the first plane coordinates of the second intersection point of the second edge and the third edge; Determining the relative position of the height measuring device and the imaging device based on the first plane coordinates and the second plane coordinates of the first intersection point includes: The relative positions of the height measuring device and the imaging device are determined based on the first plane coordinates and the second plane coordinates of the first intersection point, and the first plane coordinates and the second plane coordinates of the second intersection point.

7. The method for calibrating the relative position of the height measuring device and the imaging device according to claim 6, characterized in that, Determining the relative position of the height measuring device and the imaging device based on the first plane coordinates and the second plane coordinates of the first intersection point, and the first plane coordinates and the second plane coordinates of the second intersection point, includes: The first relative coordinate in the relative position is determined based on the difference between the first plane coordinates and the first coordinate value in the second plane coordinates of the first intersection point, and the difference between the first plane coordinates and the first coordinate value in the second plane coordinates of the second intersection point. The second relative coordinate in the relative position is determined based on the difference between the first plane coordinates and the second coordinates of the second plane at the first intersection point, and the difference between the first plane coordinates and the second coordinates of the second plane at the second intersection point.

8. The method for calibrating the relative position of the height measuring device and the imaging device according to claim 1, characterized in that, The calibration plate is polygonal.

9. A relative position calibration device for a height measuring device and an imaging device, characterized in that, include: The edge point coordinate determination module is used to determine the planar coordinates of at least two points on each of the at least two edges of the calibration plate based on the height measurement results obtained by the relative movement of the height measuring device and the calibration plate in at least two directions. The boundary equation determination module is used to determine the boundary equations corresponding to at least two edges based on the planar coordinates of at least two points on each of the at least two edges on the calibration plate. The intersection point coordinate determination module is used to determine the first planar coordinates of at least one intersection point of at least two of the edges based on the boundary equations corresponding to at least two of the edges respectively. A grasping module is used to grasp the second planar coordinates of at least one of the intersection points through the imaging device; The relative position determination module is used to determine the relative position of the height measuring device and the imaging device based on the first plane coordinates and the second plane coordinates corresponding to at least one identical intersection point.

10. A system for calibrating the relative position of a height measuring device and an imaging device, characterized in that, include: The system includes a height measuring device, an imaging device, a machine base, and a processing module; the machine base includes a platform and a column; the platform is used to support a calibration plate. The processing module is electrically connected to the height measuring device and the imaging device, respectively, and the height measuring device and the imaging device are fixed on the column. The processing module is used to determine the planar coordinates of at least two points on each of the at least two edges of the calibration plate based on the height measurement results obtained by the relative movement of the height measuring device and the calibration plate in at least two directions; to determine the boundary equations corresponding to the at least two edges based on the planar coordinates of the at least two edges; to determine the first planar coordinates of at least one intersection point of the at least two edges based on the boundary equations corresponding to the at least two edges; to capture the second planar coordinates of at least one intersection point through the imaging device; and to determine the relative position of the height measuring device and the imaging device based on the first planar coordinates and the second planar coordinates corresponding to at least one identical intersection point.

Images