CN116245959A - Camera pose calibration device and camera pose calibration method for roller surface imaging - Google Patents

Abstract

The application discloses a camera pose calibration device and a camera pose calibration method for roll surface imaging, and belongs to the technical field of lithium battery manufacturing. The camera pose calibration device comprises: the target is used for being attached to the guide roller and is provided with a target imaging line which is suitable for being parallel to the axial direction of the guide roller; the calibrating tool comprises a connecting arm, clamping arms and a centering mark, wherein the clamping arms are connected to two ends of the connecting arm, the connecting arm is provided with a first plane perpendicular to the symmetrical plane of the calibrating tool, the two clamping arms are provided with second planes which are arranged oppositely, the two second planes are in mirror symmetry relative to the symmetrical plane, the distance between the two second planes gradually increases from the direction close to the connecting arm to the direction far away from the connecting arm, the symmetrical plane penetrates through the centering mark, and the two second planes are suitable for clamping guide rollers; the angle gauge is used for being placed on the first plane. Through the setting of above-mentioned target, demarcation frock and angle appearance, solved the problem that the roll surface formation of image does not have the benchmark to the accuracy to polar plate defect detection has been ensured.

Description

Camera pose calibration device and camera pose calibration method for roller surface imaging

Technical Field

The application belongs to the technical field of lithium battery manufacturing, and particularly relates to a camera pose calibration device and a camera pose calibration method for roll surface imaging.

Background

In the manufacturing process of the lithium battery, the defect of the surface of the pole piece can be detected by adopting the imaging of the roller surface of the camera, in the related technology, imaging adjustment is carried out by an assembling and adjusting person through adjusting the imaging angle of the camera, the angle of the light source and the like until the detection point is illuminated, and the camera can clearly image the surface of the pole piece. However, the inventor researches find that firstly, because the roller surface images, the imaging point is positioned on the surface of the round guide roller, the imaging angle of the camera cannot be determined through the attitude angle of the camera, so that the imaging angle is inconsistent with the imaging angle of theoretical design, and the imaging angle of the camera is different after each installation and adjustment; secondly, as most of the defects of the pole piece are three-dimensional defects, the patterns of the three-dimensional defects when photographed at different angles are different, so that the same defect can show different shapes and gray changes on different detection systems, and the judgment of the software algorithm on the defect types is affected.

Disclosure of Invention

The present application aims to solve at least one of the technical problems existing in the prior art. Therefore, the application provides a camera pose calibration device and a camera pose calibration method for roller surface imaging, which solve the problem that whether the roller surface imaging is consistent with the design after the adjustment cannot be confirmed without a reference.

In a first aspect, the present application provides a camera pose calibration device for roll surface imaging, comprising:

a target for overlaying a guide roller and having a target imaging line adapted to be parallel to an axial direction of the guide roller;

the calibrating tool comprises a connecting arm, clamping arms connected to two ends of the connecting arm and a centering mark, wherein the connecting arm is provided with a first plane perpendicular to a symmetrical plane of the calibrating tool, the two clamping arms are provided with second planes which are arranged oppositely, the two second planes are in mirror symmetry relative to the symmetrical plane, the distance between the two second planes is gradually increased from a direction close to the connecting arm to a direction far away from the connecting arm, the symmetrical plane penetrates through the centering mark, and the two second planes are suitable for clamping the guide roller;

and the angle gauge is used for being placed on the first plane.

According to the camera pose calibration device for roller surface imaging, through the setting of the target, the calibration tool and the angle meter, the position of the target imaging line on the roller surface is determined according to the target, and then the specific position of the camera imaging point on the roller surface is further determined by means of the calibration tool, so that the problem that whether the roller surface imaging is consistent with the design after the assembly and adjustment cannot be confirmed without a reference is solved, and further the accuracy of defect detection of the polar plate is ensured.

According to an embodiment of the present application, the calibration fixture further comprises:

the sliding block is assembled on the connecting arm in a sliding mode, the centering mark is located at the bottom of the sliding block, and the sliding direction of the sliding block is parallel to the central axis of the calibration tool.

According to one embodiment of the present application, the connecting arm includes:

the first arm is connected between the two clamping arms, and the first plane is arranged on the first arm;

and the second arm is connected between the two clamping arms, the second arm is spaced from the first arm, and the sliding block is slidingly assembled on the second arm.

According to one embodiment of the present application, the connecting arm further comprises:

the fixed plate, the second arm is equipped with the breach, the slider sliding fit in the breach, the fixed plate with the second arm is connected, and seals the breach.

According to one embodiment of the application, the connecting arm is provided with a detachable first connecting structure for fixing the angle gauge.

According to one embodiment of the application, the clamping arm is provided with a detachable second connection structure for fixing the calibration fixture with the guide roller.

According to one embodiment of the application, the target is rectangular, and the width of the target is equal to the circumference of the guide roller, and the target imaging line is parallel to the long side of the target.

According to one embodiment of the present application, the four corners of the target are provided with alignment marks.

In a second aspect, the present application provides a camera pose calibration method using any one of the calibration devices described above, the camera pose calibration method comprising:

attaching a target to a guide roller, wherein a target imaging line of the target is parallel to the axial direction of the guide roller;

placing a calibration tool on the guide roller, and aligning a centering mark of the calibration tool with the target imaging line;

installing an angle meter on a first plane of the calibration tool;

synchronously rotating the guide roller, the target and the calibration tool until the measured value of the angle meter is equal to a target value;

and keeping the guide roller and the target motionless, and adjusting the pose of the camera by taking the target imaging line as a reference.

According to the camera pose calibration method, through the arrangement of the steps and the cooperation of the camera pose calibration device, relevant operators operate according to standard calibration process steps, the blindness of on-site adjustment is reduced, and therefore the influence of human factors on imaging quality is reduced.

According to an embodiment of the present application, the adjusting the pose of the camera based on the target imaging line includes:

adjusting the pitching angle of the camera to a design angle;

horizontally moving the camera to image at least one point on the display target imaging line;

the horizontal angle of the camera is adjusted to enable imaging to coincide with the target imaging line.

Additional aspects and advantages of the application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the application.

Drawings

The foregoing and/or additional aspects and advantages of the present application will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings, wherein:

fig. 1 is a schematic diagram of a camera pose calibration device for roll surface imaging according to an embodiment of the present application;

fig. 2 is a schematic structural diagram of a target of a camera pose calibration device for roll surface imaging according to an embodiment of the present application;

fig. 3 is one of schematic structural diagrams of a calibration tool of a camera pose calibration device for roll surface imaging according to an embodiment of the present application;

fig. 4 is a second schematic structural diagram of a calibration tool of a camera pose calibration device for roll surface imaging according to an embodiment of the present application;

fig. 5 is one of installation schematic diagrams of a calibration tool and a guide roller of a camera pose calibration device for roller surface imaging provided in an embodiment of the present application;

FIG. 6 is a second schematic view of the installation of a camera pose calibration device for roll surface imaging and a guide roll provided in an embodiment of the present application;

fig. 7 is a flow chart of a camera pose calibration method according to an embodiment of the present application;

fig. 8 is an operation schematic diagram of step 510 in the camera pose calibration method provided in the embodiment of the present application;

fig. 9 is an operation schematic diagram of step 520 in the camera pose calibration method provided in the embodiment of the present application;

fig. 10 is an operation schematic diagram of step 530 in the camera pose calibration method provided in the embodiment of the present application.

Reference numerals:

the camera pose calibration device 100 and the angle meter 140 are used for roller surface imaging;

a target 110, a target imaging line 111;

calibration fixture 120, connecting arm 121, first arm 122, second arm 123, clamping arm 124, centering mark 125, symmetry plane 126, first plane 127, second plane 128, slider 129, first connecting structure 130, second connecting structure 131, and fixing plate 132;

a guide roller 200;

camera position A1, camera normal L1, imaging point tangent plane m, imaging angle alpha;

camera position two A2, camera normal two L2, imaging point tangent plane two n, imaging angle two beta.

Detailed Description

Embodiments of the present application are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary only for the purpose of explaining the present application and are not to be construed as limiting the present application.

The application discloses a camera pose calibration device 100 for roll surface imaging.

A camera pose calibration device 100 for roll surface imaging according to an embodiment of the present application is described below with reference to fig. 1 to 6 and fig. 8 to 10.

In some embodiments, as shown in fig. 1-6 and 8-10, a camera pose calibration device 100 for roll surface imaging includes: target 110, calibration fixture 120, and goniometer 140.

The targets 110 are for attaching to the guide roller 200, and the targets 110 have target imaging lines 111 adapted to be parallel to the axial direction of the guide roller 200.

The targets 110 may be used for calibration of camera imaging lines, as shown in fig. 2, in the deployed state, the targets 110 may be rectangular in shape, with the length of the targets 110 being equal to the length of the guide roller 200, or the length of the targets 110 being slightly less than the length of the guide roller 200, such as, in some embodiments, the length of the targets 110 being slightly less than the length of the guide roller 200, as shown in fig. 8-10.

The target imaging line 111 may be disposed on the target 110, and the target imaging line 111 may be disposed 1 or more, wherein the plurality represents 2 or more.

In actual implementation, the target 110 is coated on the surface of the guide roller 200. At this time, the target 110 is rolled into a cylinder, and the target 110 is closely adhered to the roller surface of the guide roller 200, and the target imaging line 111 on the adhered target 110 is axially parallel to the guide roller 200.

By setting the target 110, the target imaging line 111 on the target 110 is accurately marked and fixed.

The calibration fixture 120 comprises a connecting arm 121, a clamping arm 124 and a centering mark 125, wherein the clamping arm 124 is connected to two ends of the connecting arm 121, the connecting arm 121 is provided with a first plane 127 perpendicular to a symmetrical plane 126 of the calibration fixture 120, the two clamping arms 124 are provided with second planes 128 which are oppositely arranged, the two second planes 128 are in mirror symmetry relative to the symmetrical plane 126, the distance between the two second planes 128 is gradually increased from a direction close to the connecting arm 121 to a direction far away from the connecting arm 121, the symmetrical plane 126 penetrates through the centering mark 125, and the two second planes 128 are suitable for clamping the guide roller 200.

The calibration fixture 120 may be used for calibrating a camera imaging point, as shown in fig. 3-5, two clamping arms 124 of the calibration fixture 120 may be provided, the two clamping arms 124 are separately provided, and the two clamping arms 124 are connected through a connecting arm 121 of the calibration fixture 120, the two clamping arms 124 and the connecting arm 121 are fixedly connected in an integrated manner, a V-shaped opening may be formed below the two clamping arms 124, and a V-shaped opening below may be used for placing the guide roller 200.

As shown in fig. 5, the two clamping arms 124 may be mirror symmetrical with respect to the symmetry plane 126 of the calibration fixture 120, the first plane 127 of the calibration fixture 120 may be perpendicular to the symmetry plane 126, the two clamping arms 124 may clamp the guide roller 200 coated with the target 110, the two clamping arms 124 may abut against the roller surface of the guide roller 200, the two clamping arms 124 are tangent to the roller surface of the guide roller 200, and the two tangent planes of the two clamping arms 124 and the guide roller 200 are the two second planes 128.

It will be appreciated that the greater the angle of the V-shaped opening of the two clamping arms 124, the closer the guide roller 200 is to the connecting arm 121 of the calibration fixture 120, and similarly, the smaller the angle of the V-shaped opening of the two clamping arms 124, the further the guide roller 200 is from the connecting arm 121 of the calibration fixture 120.

In actual execution, the calibration fixture 120 clamps the guide roller 200 coated with the target 110, the two clamping arms 124 of the calibration fixture 120 stop against the roller surface of the guide roller 200 at this time, and the guide roller 200 is rotated to align the target imaging line 111 on the roller surface with the centering mark 125 of the calibration fixture 120.

Through the setting of the calibration fixture 120, alignment of the target imaging line 111 and the centering mark 125 after the fixture is fixed with the guide roller 200 is achieved.

The angle gauge 140 is configured to be disposed on the first plane 127.

The angle gauge 140 may be used to measure the angle between the calibration fixture 120 and the horizontal plane, as shown in fig. 6, the angle gauge 140 may be disposed above the calibration fixture 120, and the contact surface between the angle gauge 140 and the calibration fixture 120 is the first plane 127.

In practical implementation, the calibration fixture 120 starts to rotate when in use, the symmetrical plane 126 of the calibration fixture 120 and the first plane 127 of the calibration fixture 120 deflect in space, the angle meter 140 displays an included angle between the first plane 127 of the calibration fixture 120 and the horizontal plane, and the displayed angle value is equal to the included angle between the symmetrical plane 126 of the calibration fixture 120 and the vertical plane because the first plane 127 of the calibration fixture 120 is perpendicular to the symmetrical plane 126 of the calibration fixture 120, and the displayed angle value is equal to the included angle between the central line of the calibration fixture 120 and the vertical plane because the central line of the calibration fixture 120 is in the symmetrical plane 126.

Through the arrangement of the angle gauge 140, the accurate control of the levelness of the calibration tool 120 is realized.

It should be noted that, as shown in fig. 1, when the camera is at the camera position A1, a tangent plane formed by the camera and the surface of the guide roller 200 is an imaging point tangent plane m, a normal line corresponding to the imaging point is a camera normal line L1, and an included angle between the camera normal line L1 and an imaging line of the camera is an imaging angle α; when the camera is at the camera position two A2, the tangent plane formed by the camera and the surface of the guide roller 200 is the imaging point tangent plane two n, the normal line corresponding to the imaging point is the camera normal line two L2, the included angle between the camera normal line two L2 and the imaging line of the camera is the imaging angle two beta, and the camera position one A1, the camera normal line one L1, the imaging point tangent plane one m and the imaging angle one alpha are not in one-to-one correspondence with the camera position two A2, the camera normal line two L2, the imaging point tangent plane two n and the imaging angle two beta.

Therefore, the imaging angle is influenced by the change of the position of the camera due to the fact that the imaging point is positioned on the circumferential roller surface, even if the angle of the camera is not changed, the imaging angle of the camera is greatly deviated due to the fact that the spatial position of the camera is deviated, and therefore the position of the roller surface where the imaging point is positioned is ensured to be consistent with the design position through a certain adjustment mode, and the imaging angle can be ensured to be consistent with the design value.

In actual implementation, the target 110 is coated on the guide roller 200, the target imaging line 111 axially parallel to the guide roller 200 is calibrated, the guide roller 200 coated with the target 110 is clamped by the calibration tool 120, after the guide roller 200 is rotated to align the centering mark 125 of the calibration tool 120 with the target imaging line 111 on the roller surface, the calibration tool 120, the guide roller 200 and the target 110 are synchronously rotated, when the angle gauge 140 displays a set value, the rotation is stopped, the calibration tool 120, the guide roller 200 and the target 110 are fixed, the centering mark 125 is still aligned with the target imaging line 111 on the roller surface, finally, the camera is adjusted according to the target imaging line 111 at the moment, a pole roll with a certain length can be wound on the guide roller 200, and the adjusted camera can photograph the surface of the pole roll on the guide roller 200, so that the detection of the surface defects of the pole roll is completed.

According to the camera pose calibration device 100 for roller surface imaging, through the arrangement of the target 110, the calibration tool 120 and the angle meter 140, the position of the target imaging line on the roller surface is determined according to the target, and then the specific position of the camera imaging point on the roller surface is further determined by means of the calibration tool, so that the problem that whether the roller surface imaging is consistent with the design after the assembly and adjustment cannot be confirmed without a reference is solved, and further the accuracy of defect detection of a polar plate is ensured.

In some embodiments, as shown in fig. 3-4 and 6, the calibration fixture 120 may further include: a slider 129.

The slider 129 may be slidably mounted on the connection arm 121, and the centering mark 125 may be located at the bottom of the slider 129, and the sliding direction of the slider 129 may be parallel to the central axis of the calibration fixture 120.

The slider 129 may be used to assist in moving the centering mark 125, as shown in fig. 3-4 and 6, the slider 129 may include two lugs and a block, one lug may be disposed above the block, the other lug may be disposed below the block, the cross-sectional area of the two lugs may be larger than the cross-sectional area of the block, the block may slide up and down on the connecting arm 121, and the centering mark 125 may be disposed on the lug below the block.

In actual implementation, when the slider 129 drives the centering mark 125 thereon to press downwards, the lugs below the block contact the roller surface of the guide roller 200, the centering mark 125 on the lugs below the block is aligned with the target imaging line 111 on the roller surface, and at this time, the lugs above the block stop against the connecting arm 121 of the calibration fixture 120, preventing the slider 129 from continuing to descend; when the slider 129 drives the centering mark 125 thereon to rise upwards, the lugs below the block are out of contact with the roller surface of the guide roller 200 until the lugs below the block abut against the connecting arms 121 of the calibration fixture 120.

Through the setting of the slide block 129, the alignment of the centering mark 125 on the calibration tool 120 and the position of the target imaging line 111 on the roller surface can be realized, and the design of the slide block 129 structure is matched, so that the centering mark 125 is ensured to move in a controllable range and is convenient to operate while the structural reliability of the camera pose calibration device 100 for roller surface imaging is not affected.

In some embodiments, as shown in fig. 3-4 and 6, the connecting arm 121 may include: a first arm 122 and a second arm 123.

The first arm 122 may be connected between two clamping arms 124, and a first plane 127 may be provided at the first arm 122.

The first arm 122 may be used to mount the angle gauge 140, as shown in fig. 3-4 and 6, the upper top surface of the first arm 122 may be the first plane 127 of the calibration fixture 120, and the angle gauge 140 may be disposed on the upper top surface of the first arm 122, that is, the connection surface of the angle gauge 140 and the first arm 122 of the connection arm 121 is the first plane 127 of the calibration fixture 120.

The second arm 123 may be connected between two clamping arms 124, the second arm 123 may be spaced apart from the first arm 122, and the slider 129 may be slidably mounted to the second arm 123.

The second arm 123 may be used to mount the slider 129, as shown in fig. 3, the first arm 122 and the second arm 123 may be integrally formed, the first arm 122 may be disposed above the second arm 123, and an intermediate area formed by disposing the first arm 122 separately from the second arm 123 may be an area where the slider 129 is used to slide.

In practical implementation, the angle gauge 140 is disposed on the first plane 127, when the calibration fixture 120 starts to rotate, the angle gauge 140 can measure the included angle between the first plane 127 and the horizontal plane, and in the process of pressing the slider 129 down to contact with the guide roller 200, the slider 129 drives the centering mark 125 thereon to move downward until the lug located above the block abuts against the second arm 123 of the connecting arm 121, at this time, the slider 129 abuts against the guide roller 200, and the centering mark 125 on the lug below the block aligns with the target imaging line 111 on the roller surface.

Through the first arm 122 and the second arm 123, the installation of the angle gauge 140 and the sliding assembly of the sliding block 129 are realized, firstly, the separation of the first arm 122 and the second arm 123 provides enough sliding space for the sliding block 129, a precondition is provided for the subsequent centering of the marking 125 on the Ji Babiao imaging line 111, and meanwhile, the limiting effect on the sliding block 129 is also achieved by matching with the structural design of the sliding block 129; secondly, the upper and lower layers are clear, the structure is simple, the use threshold of the camera pose calibration device 100 for roller surface imaging is reduced, and the assembly of related personnel is facilitated.

In some embodiments, as shown in fig. 3, the connecting arm 121 may further include: a fixing plate 132.

The second arm 123 is provided with a notch, the slider 129 is slidably assembled in the notch, and the fixing plate 132 is connected with the second arm 123 and closes the notch.

The fixing plate 132 may be used to fix the second arm 123 to the slider 129, that is, to ensure that the slider 129 is in sliding connection with the second arm 123 so that the slider 129 is not out of contact with the second arm 123, as shown in fig. 3, the fixing plate 132 may be embedded in the second arm 123, and the fixing plate 132 and the connecting arm 121 may be connected by, but not limited to, bolting, riveting, or pin-shaft connection, for example, in some embodiments, the fixing plate 132 and the connecting arm 121 may be connected by bolting.

The notch may be used to accommodate the slider 129, as shown in fig. 3, the notch may be a square groove, the notch may be disposed between the fixed plate 132 and the second arm 123, the slider 129 may be disposed within the notch, i.e., the slider 129 is disposed between the fixed plate 132 and the second arm 123, and the slider 129 forms a sliding fit with the fixed plate 132 and the second arm 123.

In actual implementation, as shown in fig. 3, in the process of assembling the calibration fixture 120, the slider 129 is installed in the notch of the second arm 123, then the fixing plate 132 is embedded into the second arm 123, the notch with the slider 129 installed is plugged, two ends of the fixing plate 132 and corresponding positions of the second arm 123 are drilled, and finally two bolts are installed in the holes, so that the fixing connection between the fixing plate 132 and the second arm 123 is realized, the installed slider 129, the lugs above the block are arranged above the fixing plate 132 and the second arm 123 at this time, and the lugs below the block are arranged below the fixing plate 132 and the second arm 123 at this time.

Through the setting of the above-mentioned fixed plate 132, realized the slip assembly of slider 129 and second arm 123, cooperation slider 129's structural design and embedded assembly design have limited the slip scope of slider 129 in second arm 123, simultaneously, have realized the lightweight of structure, have improved the reliability of structure.

In some embodiments, as shown in fig. 3, the connecting arm 121 is provided with a detachable first connecting structure 130 for securing the goniometer 140.

The first connection structure 130 may be a removable connector, which may be a threaded connector, a snap-fit connector, or other connector, for example, in some embodiments, the first connection structure 130 is a threaded connector.

As shown in fig. 3, the first connection structure 130 may be disposed on the first arm 122 of the connection arm 121, and the first connection structure 130 may be disposed in plurality, wherein the plurality represents 2 or more, for example, in some embodiments, as shown in fig. 3, 2 first connection structures 130 are disposed on the first arm 122 of the connection arm 121.

It will be appreciated that after the calibration fixture 120 is placed on the roll surface, and the centering mark 125 on the slider 129 of the calibration fixture 120 is aligned with the target imaging line 111 mark, the angle gauge 140 may be mounted on the first arm 122 of the calibration fixture 120 through the first connection structure 130, and the mounted angle gauge 140 may be used to perform a side beam on an included angle between the first plane 127 and the horizontal plane during the rotation of the subsequent calibration fixture 120, and after the use is completed, the first connection structure 130 may be detached, so that the angle gauge 140 may be removed from the calibration fixture 120.

Through the setting of the first connecting structure 130, detachable connection of the angle meter 140 and the calibration tool 120 is realized, the overall flexibility of the camera pose calibration device 100 for roll surface imaging is improved, and the design of easy detachment also provides convenience for subsequent maintenance, maintenance and storage of the device.

In some embodiments, as shown in fig. 3, the clamping arm 124 is provided with a detachable second connection structure 131 for fixing the calibration fixture 120 with the guide roller 200.

As shown in fig. 3, the second connection structure 131 may be a connection groove, where the connection groove may be divided into a first section and a second section, the first section is a cylinder with a larger inner cross-sectional area, the second section is a cuboid with a smaller outer cross-sectional area, the second connection structure 131 may be disposed on the clamping arm 124 of the calibration fixture 120, and the first connection member may be plural, where plural means 2 or more than 2, for example, in some embodiments, as shown in fig. 3, 2 second connection structures 131 are disposed on the calibration fixture 120, that is, 1 second connection structure 131 is disposed on each of the 2 clamping arms 124 of the calibration fixture 120.

In practical implementation, the second connecting structure 131 can be detachably connected with other tools fixed with the guide roller 200, when the second connecting structure 131 is coupled with the second connecting structure 131, corresponding connecting pieces can be arranged on other tools fixed with the guide roller 200, the connecting pieces can be matched with the second connecting structure 131, and the cross section area of the first section is larger than that of the second section in the second connecting structure 131, so that the blocking of the second section cannot be broken by the part coupled with the first section in the connecting pieces, and therefore the clamping connection of the connecting pieces and the second connecting structure 131 is formed, but the connecting pieces can slide vertically relative to the second connecting structure 131, so that the detachable connection of the connecting pieces and the second connecting structure 131 is realized.

Through the setting of the second connecting structure 131, detachable connection of the guide roller 200 and the calibration tool 120 is realized, and the calibration accuracy of the calibration tool 120 is ensured, so that the operation of the camera pose calibration process is faster and more convenient, and the calibration efficiency is improved.

In some embodiments, as shown in fig. 2, the deployed target 110 may be rectangular and the width of the target 110 may be equal to the circumference of the guide roller 200 and the target imaging line 111 may be parallel to the long side of the target 110.

The rectangular target 110 includes 2 long sides and 2 short sides. The 2 long sides are parallel to each other, the 2 short sides are parallel to each other, the target imaging line 111 may be parallel to the 2 long sides, and the length of the short sides of the target 110, i.e., the width of the target 110, may be equal to the circumference of the cross section of the guide roller 200.

It will be appreciated that the target 110 is coated on the surface of the guide roller 200 as shown in fig. 8. At this time, the target 110 is rolled into a cylinder, and the target 110 is tightly attached to the roller surface of the guide roller 200, because the width of the target 110 is equal to the circumference of the cross section of the guide roller 200, then the target 110 just winds around the guide roller 200, and the two long sides of the target 110 are coincident, and because the target imaging line 111 is parallel to the long sides of the target 110, according to the rectangular self-correcting characteristic, that is, assuming that a rectangle is provided with a plurality of transverse lines parallel to the upper and lower sides, the lines on the rectangle must be parallel to the center line of the cylinder, and the characteristic is used to ensure that the target imaging line 111 on the target 110 is axially parallel to the guide roller 200 after the target 110 is attached.

Through the shape and the size design of the target 110, the situation that the target imaging line 111 inclines on the roller surface of the guide roller 200 is avoided by utilizing the mathematical theorem, and the calibration precision of the target imaging line 111 is improved.

In some embodiments, as shown in fig. 2, the four corners of the target 110 are provided with alignment indicia.

As shown in fig. 2, the target 110 of the rectangle may include an upper left vertex, a lower left vertex, an upper right vertex and a lower right vertex, where the upper left vertex, the lower left vertex, the upper right vertex and the lower right vertex are sequentially connected and closed to form the target 110 of the rectangle, and the upper left vertex, the lower left vertex, the upper right vertex and the lower right vertex may all be provided with corresponding alignment marks.

In actual implementation, as shown in fig. 8, the target 110 is coated on the surface of the guide roller 200. At this time, the target 110 is rolled into a cylinder, and the target 110 is tightly attached to the roller surface of the guide roller 200, so that the alignment mark of the upper left vertex of the target 110 coincides with the alignment mark of the lower left vertex of the target 110, the alignment mark of the upper right vertex of the target 110 coincides with the alignment mark of the lower right vertex of the target 110, and according to the self-correcting characteristic of the rectangle, that is, assuming that a plurality of transverse lines parallel to the upper and lower sides of the rectangle are arranged in parallel on the upper surface of the rectangle, the lines on the rectangle must be parallel to the center line of the cylinder, and the characteristic is used to ensure that the target imaging line 111 on the target 110 is axially parallel to the guide roller 200 after the target 110 is attached.

Through the setting of the alignment mark, 4 points of the target 110 are accurately positioned, so that the calibration precision of the target imaging line 111 is further improved, and the error rate of the pole piece detection system is reduced.

The application also discloses a camera pose calibration method using any calibration device.

A camera pose calibration method according to an embodiment of the present application is described below with reference to fig. 7 to 10.

In some embodiments, as shown in fig. 7, the camera pose calibration method includes: step 510, step 520, step 530, step 540, and step 550.

Step 510, the target 110 is attached to the guide roller 200, and the target imaging line 111 of the target 110 is parallel to the axial direction of the guide roller 200.

In actual implementation, as shown in fig. 8, the target 110 is wrapped around the guide roller 200, so that the alignment mark of the upper left vertex of the target 110 coincides with the alignment mark of the lower left vertex of the target 110, and the alignment mark of the upper right vertex of the target 110 coincides with the alignment mark of the lower right vertex of the target 110, so that no relative movement between the target 110 and the guide roller 200 is ensured under the condition of no external force, then the target 110 and the guide roller 200 are bonded by using an adhesive, and after the subsequent calibration is finished, the residual adhesive on the roller surface can be wiped clean by using a photoresist remover.

Step 520, the calibration fixture 120 is placed on the guide roller 200, and the centering mark 125 of the calibration fixture 120 is aligned with the target imaging line 111.

In actual implementation, as shown in fig. 9, two clamping arms 124 of the calibration fixture 120 are placed on the roller surface of the guide roller 200, the guide roller 200 is rotated to align the target imaging line 111 on the roller surface with the centering mark 125 of the calibration fixture 120, and after confirming that the target imaging line 111 on the roller surface is aligned with the centering mark 125 of the calibration fixture 120, the guide roller 200 is fixed with the calibration fixture 120 through the second connection structure 131.

Step 530, the angle gauge 140 is mounted on the first plane 127 of the calibration fixture 120.

In actual implementation, as shown in fig. 10, the angle gauge 140 is detachably connected to the first arm 122 of the connecting arm 121 of the calibration fixture 120 through the first connecting structure 130, at this time, the angle gauge 140 is disposed on the first plane 127 of the calibration fixture 120, after the angle gauge 140 is installed, the included angle between the first plane 127 and the horizontal plane can be measured, because the first plane 127 is perpendicular to the symmetry plane 126 of the calibration fixture 120, the displayed angle value is also equal to the included angle between the center line of the calibration fixture 120 and the vertical plane, and the center line passes through the center of the guide roller 200, and if the centering mark 125 on the calibration fixture 120 is aligned with the target imaging line 111, the center line is the imaging normal.

Step 540, synchronously rotating the guide roller 200, the target 110 and the calibration fixture 120 until the measured value of the angle gauge 140 is equal to the target value.

In actual execution, after the angle gauge 140 is installed, the target 110, the calibration fixture 120 and the guide roller 200 rotate synchronously, that is, the rotation directions and angles of the target 110, the calibration fixture 120 and the guide roller 200 are equal, until the angle gauge 140 displays a value consistent with the included angle between the imaging normal and the vertical plane in design, the target 110, the calibration fixture 120 and the guide roller 200 stop rotating.

Step 550, keeping the guide roller 200 and the target 110 motionless, and adjusting the pose of the camera based on the target imaging line 111.

In actual execution, after the rotation of the target 110, the calibration fixture 120 and the guide roller 200 is stopped, the states of the guide roller 200 and the target 110 are kept unchanged, and the position and the posture of the camera are correspondingly adjusted according to the position of the target imaging line 111 at the moment.

According to the camera pose calibration method provided by the embodiment of the application, through the arrangement of the steps 510, 520, 530, 540 and 550, the camera pose calibration device is matched, so that related operators operate according to standard calibration process steps, the blindness of on-site adjustment is reduced, and the influence of human factors on imaging quality is reduced.

In some embodiments, step 550, adjusting the pose of the camera with respect to the target imaging line 111, includes:

adjusting the pitching angle of the camera to a design angle; horizontally moving the camera to at least one point on the imaging display target imaging line 111; the horizontal angle of the camera is adjusted to coincide imaging with the target imaging line 111.

It can be understood that adjusting the pitching angle of the camera, that is, adjusting the posture of the camera itself, adjusts the imaging angle of the camera by swinging the camera up and down; horizontally moving the camera, i.e. adjusting the spatial position of the camera, and changing the horizontal distance between the camera and the guide roller 200 by moving the whole camera; the camera is adjusted in horizontal angle, that is, in posture, and is adjusted in swinging angle relative to fly swiftly of the guide roller 200 by swinging the camera right and left.

In actual implementation, after step 540 is completed, the imaging angle of the camera is changed by swinging the camera up and down until the angle of the camera is consistent with the value of the angle gauge 140, the up and down swinging is stopped, the pitching attitude of the camera at the moment is locked, then the horizontal distance between the camera and the guide roller 200 is changed by horizontally moving the whole camera until the imaging of the camera shows at least a part of the target imaging line 111, the moving camera is stopped, the spatial position of the camera at the moment is fixed, finally the fly swiftly swinging angle of the camera relative to the guide roller 200 is changed by swinging the camera left and right until the imaging of the camera shows the whole target imaging line 111, the left and right swinging is stopped, and the fly swiftly swinging attitude of the camera at the moment is locked.

Thus, through the design of the scheme, the adjustment of the spatial position and the self posture of the camera is realized, the problem that the imaging angle cannot be determined in roller surface imaging is solved by matching with the calibrated target imaging line 111, and meanwhile, the positioning precision of the camera is improved by adjusting the position and the posture separately for multiple times, so that errors caused by human factors are reduced to the greatest extent, and the sheet discharging quality of the defect detection process of the follow-up pole sheet is improved.

The terms first, second and the like in the description and in the claims, are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged, as appropriate, such that embodiments of the present application may be implemented in sequences other than those illustrated or described herein, and that the objects identified by "first," "second," etc. are generally of a type and not limited to the number of objects, e.g., the first object may be one or more. Furthermore, in the description and claims, "and/or" means at least one of the connected objects, and the character "/", generally means that the associated object is an "or" relationship.

In the description of the present application, it should be understood that the terms "center," "longitudinal," "transverse," "length," "width," "thickness," "upper," "lower," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "axial," "radial," "circumferential," and the like indicate or are based on the orientation or positional relationship shown in the drawings, merely to facilitate description of the present application and to simplify description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be configured and operated in a particular orientation, and thus should not be construed as limiting the present application.

In the description of the present application, "a first feature", "a second feature" may include one or more of the features.

In the description of the present application, the meaning of "plurality" is two or more.

In the description of this application, a first feature "above" or "below" a second feature may include both the first and second features being in direct contact, and may also include the first and second features not being in direct contact but being in contact by another feature therebetween.

In the description of this application, a first feature being "above," "over" and "on" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicating that the first feature is higher in level than the second feature.

In the description of the present specification, reference to the terms "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present application. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the present application have been shown and described, it will be understood by those of ordinary skill in the art that: many changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the application, the scope of which is defined by the claims and their equivalents.

Claims (10)

1. A camera position appearance calibration device for roll surface formation of image, characterized by, include:

a target for overlaying a guide roller and having a target imaging line adapted to be parallel to an axial direction of the guide roller;

the calibrating tool comprises a connecting arm, clamping arms connected to two ends of the connecting arm and a centering mark, wherein the connecting arm is provided with a first plane perpendicular to a symmetrical plane of the calibrating tool, the two clamping arms are provided with second planes which are arranged oppositely, the two second planes are in mirror symmetry relative to the symmetrical plane, the distance between the two second planes is gradually increased from a direction close to the connecting arm to a direction far away from the connecting arm, the symmetrical plane penetrates through the centering mark, and the two second planes are suitable for clamping the guide roller;

and the angle gauge is used for being placed on the first plane.

2. The camera pose calibration device for roll surface imaging of claim 1, wherein the calibration fixture further comprises:

the sliding block is assembled on the connecting arm in a sliding mode, the centering mark is located at the bottom of the sliding block, and the sliding direction of the sliding block is parallel to the central axis of the calibration tool.

3. The camera pose calibration device for roll surface imaging of claim 2, wherein the connecting arm comprises:

the first arm is connected between the two clamping arms, and the first plane is arranged on the first arm;

and the second arm is connected between the two clamping arms, the second arm is spaced from the first arm, and the sliding block is slidingly assembled on the second arm.

4. A camera pose calibration device for roll surface imaging according to claim 3 wherein said connecting arm further comprises:

the fixed plate, the second arm is equipped with the breach, the slider sliding fit in the breach, the fixed plate with the second arm is connected, and seals the breach.

5. The camera pose calibration device for roll surface imaging according to claim 1, wherein the connecting arm is provided with a detachable first connecting structure for fixing an angle meter.

6. The camera pose calibration device for roll surface imaging according to claim 1, wherein the clamping arm is provided with a detachable second connection structure for fixing the calibration fixture with the guide roll.

7. The camera pose calibration device for roll surface imaging according to any of claims 1 to 6 wherein the target is rectangular and the width of the target is equal to the circumference of the guide roll, the target imaging line being parallel to the long side of the target.

8. The camera pose calibration device for roll surface imaging according to claim 7, wherein four corners of the target are provided with alignment marks.

9. A camera pose calibration method using the calibration device according to any one of claims 1 to 8, comprising:

attaching a target to a guide roller, wherein a target imaging line of the target is parallel to the axial direction of the guide roller;

placing a calibration tool on the guide roller, and aligning a centering mark of the calibration tool with the target imaging line;

installing an angle meter on a first plane of the calibration tool;

synchronously rotating the guide roller, the target and the calibration tool until the measured value of the angle meter is equal to a target value;

and keeping the guide roller and the target motionless, and adjusting the pose of the camera by taking the target imaging line as a reference.

10. The method for calibrating a camera pose of a calibration device according to claim 9, wherein adjusting the camera pose with the target imaging line as a reference comprises:

adjusting the pitching angle of the camera to a design angle;

horizontally moving the camera to image at least one point on the display target imaging line;

the horizontal angle of the camera is adjusted to enable imaging to coincide with the target imaging line.

Images