CN216118852U - Cylindrical surface visual target acquisition equipment and calibration device of linear scanning mechanism thereof - Google Patents
Cylindrical surface visual target acquisition equipment and calibration device of linear scanning mechanism thereof Download PDFInfo
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- CN216118852U CN216118852U CN202122500251.4U CN202122500251U CN216118852U CN 216118852 U CN216118852 U CN 216118852U CN 202122500251 U CN202122500251 U CN 202122500251U CN 216118852 U CN216118852 U CN 216118852U
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Abstract
The utility model provides a cylindrical surface visual target obtaining device and a calibration device of a line scanning mechanism thereof, which are used for calibrating the line scanning mechanism for visually acquiring the cylindrical surface of a workpiece, wherein the line scanning mechanism is provided with a base, a bearing platform for bearing the workpiece, a rotation driving mechanism for driving the workpiece to rotate and a line scanning camera, and is characterized by comprising: the angle adjusting mechanism is arranged between the base and the bearing platform and used for adjusting the plane angle of the camera chip of the bearing platform; the inclination angle adjusting mechanism is arranged between the base and the bearing platform and is used for adjusting an included angle between the bearing platform and the plane of the camera chip; the control unit is in communication connection with the line scanning camera and is used for receiving and analyzing the images acquired by the line scanning camera, and the control unit is also used for controlling the angle adjusting mechanism and the inclination angle adjusting mechanism to carry out angle adjustment and controlling the rotating speed of the rotating driving mechanism; and the calibration column is provided with a first calibration line, a second calibration line and a calibration circle which are parallel to the axis.
Description
Technical Field
The utility model belongs to the field of machine vision, and relates to a cylindrical visual target acquisition device and a calibration device of a line scanning mechanism thereof.
Background
The line scanning camera can capture a high-resolution image of a uniform-speed moving object, is suitable for acquiring a high-speed or high-resolution image, and is suitable for high-precision detection of curved surfaces such as bearings and the like and detection and measurement of the patterns on the surfaces of cylindrical products in industry.
Due to the reasons of mechanical installation and the like, the line scanning camera is difficult to be parallel to the cylindrical surface of the workpiece to be detected, so that the acquired image is deformed, and finally, a picture which can be used for measurement or defect detection is difficult to obtain. In the existing method, the linear scanning camera and the measuring cylindrical surface are ensured to be parallel by means of mechanical limit and the like, and an undeformed picture is obtained by setting a proper speed, but the following problems still exist: firstly, the parallel processing difficulty of the final linear scanning mechanism is very high, and the cost is not easy to control; secondly, the installation requirement is very high, and the unparallel installation of one small part can possibly cause the line scanning camera to be incapable of being used normally; thirdly, the manual setting of the running speed of the object to be measured or the line frequency parameters of the line scan camera requires multiple acquisition and multiple adjustment, the time consumption is long, the efficiency is low, and the precision is not guaranteed.
SUMMERY OF THE UTILITY MODEL
In order to solve the problems, the utility model provides a calibration device which can ensure that a linear scanning mechanism can keep parallel to a cylindrical surface of a workpiece to be detected, has controllable cost and avoids image deformation, and adopts the following technical scheme:
the utility model provides a calibration device of a line scanning mechanism for a cylindrical visual target, which is used for calibrating the line scanning mechanism for visually acquiring the cylindrical surface of a workpiece, and the line scanning mechanism is provided with a base, a bearing platform for bearing the workpiece, a rotation driving mechanism for driving the workpiece to rotate and a line scanning camera, and is characterized by comprising: the angle adjusting mechanism is arranged between the base and the bearing platform and used for adjusting the plane angle of the camera chip of the bearing platform; the inclination angle adjusting mechanism is arranged between the base and the bearing platform and is used for adjusting an included angle between the bearing platform and the plane of the camera chip; the control unit is in communication connection with the line scanning camera and is used for receiving and analyzing the images acquired by the line scanning camera, and the control unit is also used for controlling the angle adjusting mechanism and the inclination angle adjusting mechanism to carry out angle adjustment and controlling the rotating speed of the rotating driving mechanism; and the calibration column is used for calibrating the linear scanning mechanism, wherein a first calibration line parallel to the axis, a plurality of second calibration lines perpendicular to the first calibration line and a calibration circle are arranged on the cylindrical surface of the calibration column.
The calibration device of the line scanning mechanism for the cylindrical visual target provided by the utility model can also have the technical characteristics that the inclination angle adjusting mechanism comprises an adjusting plate, a first rotating shaft and a first motor, the first motor drives the adjusting plate to swing relative to the base through the first rotating shaft so as to change the inclination angle relative to the base, the angle adjusting mechanism comprises a second rotating shaft and a second motor, and the second motor drives the adjusting plate to change the angle through the second rotating shaft.
The utility model also provides a cylindrical visual target acquisition device, which is used for acquiring the cylindrical image of the workpiece and is characterized by comprising the following components: a calibration device; the line scanning mechanism comprises a base, a bearing platform for bearing the workpiece, a rotation driving mechanism for driving the workpiece to rotate and a line scanning camera, wherein the bearing platform is arranged on the base, the rotation driving mechanism is arranged on the bearing platform, the line scanning camera is used for acquiring a cylindrical image of the workpiece, and the calibration device consists of the calibration device of the line scanning mechanism for the cylindrical visual target.
The cylindrical visual target acquisition equipment provided by the utility model can also have the technical characteristics that the rotary driving mechanism comprises a motor and a plurality of rollers arranged on the bearing platform side by side, and the motor is used for driving the rollers to rotate.
The equipment for acquiring the cylindrical visual target provided by the utility model also has the technical characteristics that the line scanning mechanism further comprises a light source for externally supplementing light to the calibration column.
Utility model with the functions and effects
The equipment for acquiring the cylindrical visual target and the calibration device of the linear scanning mechanism thereof comprise an angle adjusting mechanism, an inclination angle adjusting mechanism, a control unit and a calibration column, and are used for calibrating the linear scanning mechanism for visually acquiring the cylindrical surface of the workpiece. The calibration column is provided with a first calibration line, a second calibration line and a calibration circle, when the linear scanning camera collects the cylindrical surface of the calibration column, the control unit controls the angle adjusting mechanism, the inclination angle adjusting mechanism and the rotation driving mechanism in the linear scanning mechanism to respectively calibrate the plane angle of the camera chip of the bearing platform, the included angle between the bearing platform and the camera chip plane and the rotation speed of the rotation driving mechanism according to the display condition of a calibration graph corresponding to the calibration line and the calibration circle of the calibration column in the collected cylindrical surface image, so that a complete, clear and deformation-free cylindrical surface image is obtained.
The calibration device of the linear scanning mechanism for the cylindrical visual target enables a workpiece to be detected to be kept in a relatively parallel state with the linear scanning camera in the working process of the linear scanning mechanism, achieves the effect that the linear scanning camera can clearly and completely collect images of the cylindrical surface of the workpiece to be detected, solves the problem of image deformation caused by incomplete matching of relative movement formed by rotating speed and the collecting rate of the linear scanning camera, and avoids the phenomena of high consumption, low efficiency, incapability of guaranteeing precision and the like when manual parameter adjustment is carried out on the linear scanning mechanism.
Drawings
FIG. 1 is a schematic diagram of an apparatus for acquiring a cylindrical visual target according to an embodiment of the present invention;
FIG. 2 is a schematic view of a calibration column in the calibration device in an embodiment of the present invention;
FIG. 3 is an expanded schematic view of a calibration post in an embodiment of the present invention;
FIG. 4 is a partial schematic view of a calibration arrangement in an embodiment of the utility model;
FIG. 5 is a flowchart illustrating the operation of the calibration apparatus of the line-scan mechanism for cylindrical visual targets according to an embodiment of the present invention.
Detailed Description
In order to make the technical means, the creation features, the achievement objects and the efficacy of the present invention easy to understand, the following describes a cylindrical visual target acquisition device and a calibration device of a line scanning mechanism thereof in detail with reference to the embodiments and the accompanying drawings.
< example >
FIG. 1 is a schematic diagram of an apparatus for acquiring a cylindrical visual target according to an embodiment of the present invention.
As shown in fig. 1, the acquisition apparatus 100 includes a line scan mechanism, a calibration device, and a light source 20.
The line scanning mechanism is provided with a base 15, a bearing platform 11 arranged on the base 15 and used for bearing the workpiece, a rotation driving mechanism for driving the workpiece to rotate on the bearing platform 11 and a line scanning camera 12.
The rotation driving mechanism comprises a motor (not shown in the figure) and a roller 131 and a roller 132 which are arranged on the bearing platform 11 side by side, wherein the motor can drive the rollers to rotate, so that when a workpiece is placed on the roller 131 and the roller 132, the workpiece can rotate at a constant speed along with the rotation speed of the rollers to match with the image acquisition of the line scanning camera 12.
The calibration device has a calibration column 14, an angle adjustment mechanism 16, a tilt angle adjustment mechanism 17, and a control unit (not shown in the figure).
Fig. 2 is a schematic view of a calibration column in the calibration device in the embodiment of the present invention, and fig. 3 is a schematic view of an expanded calibration column in the embodiment of the present invention.
As shown in fig. 2 and 3, the calibration column 14 has a cylindrical surface provided with a first calibration line 141 parallel to the axis, 10 second calibration lines 142 perpendicular to the first calibration line, and a calibration circle 143.
Fig. 4 is a partial schematic view of a calibration apparatus in an embodiment of the present invention.
As shown in fig. 4, the reclining mechanism 17 includes an adjustment plate 171, a first rotating shaft 172, and a first motor (not shown).
In this embodiment, the base 15 is provided with a protruding portion 151 protruding upward, and the adjusting plate 171 is hinged to the top end of the protruding portion 151 through the first rotating shaft 172. The length direction of the first rotating shaft 172 is parallel to the plane of the adjusting plate 171 and the base 15, so that a structure similar to a seesaw is formed between the adjusting plate 171 and the base 15, and the adjusting plate 171 can swing relative to the base 15 through the first rotating shaft 172 to change the inclination angle relative to the base 15. In addition, a driven gear is disposed on the adjusting plate 171 near the first rotating shaft 172, a driving gear is disposed on an output end of the first motor, and the driven gear and the driving gear are engaged with each other to enable the first motor to drive the adjusting plate 171 to change the inclination angle.
The angle adjustment mechanism 16 includes a second rotating shaft 161 and a second motor (not shown). The axial direction of the second shaft 161 is perpendicular to the adjusting plate 171, and the supporting platform 11 is rotatably connected to the adjusting plate 171 through the second shaft 161. In this embodiment, the bearing platform 11 is substantially parallel to the adjusting plate 171, and the bearing platform 11 can rotate relative to the adjusting plate 171 through the second rotating shaft 161 to change the plane angle between the bearing platform 11 and the adjusting plate 171. In addition, similar to the first motor, a driven gear is disposed at the position of the second rotating shaft 161 on the bottom surface of the supporting platform 11, and a driving gear is disposed at the output end of the second motor, and the driven gear and the driving gear are engaged with each other so that the second motor can drive the adjusting plate 171 to change the angle.
The control unit is in communication connection with the line scan camera 12 and can receive and analyze the images acquired by the line scan camera 12; meanwhile, the control unit is electrically connected with the rotation driving mechanism, the angle adjusting mechanism and the inclination angle adjusting mechanism, and can send out electric signals to control the work of the mechanisms, and the control unit comprises: controlling the rotating speed in the rotary driving mechanism (namely controlling the output rotating speed of a motor in the mechanism so as to control the rotating speed of the two rollers to control the rotating speed of the workpiece); controlling an angle adjusting mechanism to adjust the plane angle of the camera chip of the bearing platform 11; the inclination angle adjusting mechanism is controlled to adjust the included angle between the bearing platform 11 and the plane of the camera chip.
The light source 20 is disposed in the middle of the line scan camera 12 and the carrying platform 11 and in the space above the calibration column 14, and is used for supplementing light to the calibration column 14 from the outside.
FIG. 5 is a flowchart illustrating the operation of the calibration apparatus of the line-scan mechanism for cylindrical visual targets according to an embodiment of the present invention.
As shown in fig. 5, the work flow of the calibration apparatus of the line-scan mechanism for a cylindrical visual target includes the following steps:
step S1, correctly installing the calibration device, resetting all the parameter settings of the linear scanning mechanism, the angle adjusting mechanism 16, the inclination angle adjusting mechanism 17 and the rotation driving mechanism, and initializing the hardware module in the device;
step S2, the rotation driving mechanism is started to drive the roller 131 and the roller 132 to start uniform motion, the calibration column 14 is placed on the roller 131 and the roller 132, the focal length of the lens of the line scanning camera 12 is adjusted, and the cylindrical surface of the calibration column 14 is subjected to image acquisition;
step S3, adjusting the image height when the line scan camera 12 collects the image according to the image collected in step S2 until the collected cylindrical image includes two first calibration line patterns corresponding to the first calibration line 141, and setting the adjusted image height as the image collection height;
step S4, collecting the cylindrical image of the calibration column 14 by using the line scan camera 12 at the image collecting height, obtaining the included angle between the first calibration line pattern in the collected cylindrical image and the projection of the collecting line of the line scan camera 12 on the camera chip plane, and controlling the angle adjusting mechanism 16 by the control unit to adjust the camera chip plane angle of the bearing platform 11, so that the first calibration line pattern and the projection of the collecting line of the line scan camera 12 on the camera chip plane are parallel to each other;
step S5, acquiring a cylindrical image of the calibration column 14 by using the line scan camera 12, solving a vertical included angle between the projection of the acquisition line of the line scan camera 12 on the camera chip plane and the first calibration line pattern based on the pixel positions of the line segment spacing of the 1 st to 5 th (refer to FIG. 4) and the line segment spacing of the 5 th to 10 th (refer to FIG. 4) in the second calibration line pattern corresponding to the second calibration line 142 in the acquired cylindrical image, and controlling the inclination angle adjusting mechanism 17 by the control unit to adjust the included angle between the bearing platform 11 and the camera chip plane until the projection of the acquisition line of the line scan camera 12 on the camera chip plane is parallel to the first calibration line pattern;
step S6, acquiring a cylindrical image of the calibration column 14 by using the line scan camera 12, and taking the projection of the acquisition line of the line scan camera 12 on the camera chip plane as a direction, acquiring a calibration circle pattern corresponding to the calibration circle 143 included in the acquired cylindrical image, and when the calibration circle pattern is displayed as an ellipse, controlling the rotation driving mechanism to adjust at least one of the rotation speed and the line frequency of the line scan camera 12 by the control unit according to the major axis and the minor axis of the ellipse and the multiple of the major axis and the minor axis until the calibration circle pattern in the cylindrical image acquired by the line scan camera 12 meets the roundness error requirement of the set precision.
In this step, the major axis is an intercept of a projection of the acquisition line of the line scan camera 12 on the camera chip plane passing through the center of the calibration circle pattern and parallel thereto, and the minor axis is an intercept of the projection of the acquisition line of the line scan camera 12 passing through the center of the calibration circle pattern and perpendicular thereto, and the roundness error requirement is specifically set according to the difference in precision of parameters such as pixels, line frequency, and definition set in line scan mechanisms of different models.
In the adjusting process of the step, only the rotating speed of the rotating driving mechanism is adjusted, and the adjustment is as follows: the rotation speed of the rotary driving mechanism is divided by the multiple of the long and short axes. In another embodiment, if the rotation speed of the rotation driving mechanism cannot be adjusted (for example, the motor in the rotation driving mechanism is a motor that cannot be adjusted), the line frequency of the line scan camera may be adjusted by: the line scan camera is multiplied by a multiple between the line frequency and the major and minor axes.
In this embodiment, in the process of acquiring the cylindrical image of the calibration column 14 by the line scan camera 12 in the calibration apparatus, the light source 20 is used to perform external light supplement on the calibration column 14.
After the calibration is completed, the calibration column 14 is taken down, the workpiece to be measured is placed on the bearing platform 11, and then the line scanning camera 12 is adopted to collect the image of the cylindrical surface of the workpiece to be measured, so that a clear, complete and deformation-free cylindrical surface image is obtained.
Examples effects and effects
The calibration device for the line scanning mechanism for the cylindrical visual target provided by the embodiment comprises an angle adjusting mechanism, an inclination angle adjusting mechanism, a control unit and a calibration column, and is used for calibrating the line scanning mechanism for visually acquiring the cylindrical surface of the workpiece.
In the embodiment, the calibration column is provided with a first calibration line, a second calibration line and a calibration circle, when the linear scanning camera collects the cylindrical surface of the calibration column, the control unit controls the angle adjusting mechanism, the inclination angle adjusting mechanism and the rotation driving mechanism in the linear scanning mechanism to respectively calibrate the camera chip plane angle of the bearing platform, the included angle between the bearing platform and the camera chip plane and the rotation speed of the rotation driving mechanism according to the display condition of a calibration graph corresponding to the calibration line and the calibration circle of the calibration column in the collected cylindrical surface image, so that a complete, clear and deformation-free cylindrical surface image is obtained.
The calibration device of the linear scanning mechanism for the cylindrical visual target enables a workpiece to be detected to be kept in a relatively parallel state with the linear scanning camera in the working process of the linear scanning mechanism, achieves the effect that the linear scanning camera can clearly and completely collect images of the cylindrical surface of the workpiece to be detected, solves the problem of image deformation caused by incomplete matching of relative movement formed by rotating speed and the collecting rate of the linear scanning camera, and avoids the phenomena of high consumption, low efficiency, incapability of guaranteeing precision and the like when manual parameter adjustment is carried out on the linear scanning mechanism.
The above-described embodiments are merely illustrative of specific embodiments of the present invention, and the present invention is not limited to the description of the above-described embodiments.
For example, in this embodiment, the angle adjustment mechanism and the tilt angle adjustment mechanism drive the rotating shaft through the motor to adjust the angle of the adjustment plate, thereby implementing the angle adjustment of the bearing platform. However, in other embodiments of the present invention, the angle adjustment mechanism and the tilt angle adjustment mechanism may also be an automatic leveling system disposed below the bearing platform, and the leveling system is connected to the rotating shaft of the bearing platform by a motor to adjust the horizontal angle and the included angle of the bearing platform (reference: he shi feng, huo shi, grand jiang hong, 2012, "design and analysis of automatic leveling platform mechanism," beijing university of information technology).
Claims (5)
1. The utility model provides a calibration device to mechanism is swept to line of cylinder vision target for the line that the cylinder of to the work piece carries out vision collection sweeps the mechanism and marks, and this line sweeps the mechanism and has the base, bear the weight of the load-bearing platform of work piece, drive the pivoted rotation drive mechanism of work piece and line sweep the camera, its characterized in that includes:
the angle adjusting mechanism is arranged between the base and the bearing platform and used for adjusting the plane angle of the camera chip of the bearing platform;
the inclination angle adjusting mechanism is arranged between the base and the bearing platform and is used for adjusting an included angle between the bearing platform and the plane of the camera chip;
a control unit which is connected with the line scanning camera in a communication way and is used for receiving and analyzing the image collected by the line scanning camera,
the control unit is also used for controlling the angle adjusting mechanism and the inclination angle adjusting mechanism to carry out angle adjustment and controlling the rotating speed of the rotating driving mechanism; and
a calibration column for calibrating the line scanning mechanism,
the calibration column is characterized in that a first calibration line parallel to the axis, a plurality of second calibration lines perpendicular to the first calibration line and a calibration circle are arranged on the cylindrical surface of the calibration column.
2. The calibration device of the line-scan mechanism for cylindrical visual targets of claim 1, wherein:
wherein the inclination angle adjusting mechanism comprises an adjusting plate, a first rotating shaft and a first motor,
the first motor drives the adjusting plate to swing relative to the base through the first rotating shaft so as to change the inclination angle relative to the base,
the angle adjusting mechanism comprises a second rotating shaft and a second motor,
the second motor drives the adjusting plate to change the angle through the second rotating shaft.
3. An apparatus for acquiring a cylindrical visual target for acquiring a cylindrical image of a workpiece, comprising:
a calibration device; and
the linear sweeping mechanism is arranged on the upper portion of the machine body,
the line scanning mechanism comprises a base, a bearing platform for bearing the workpiece, a rotation driving mechanism for driving the workpiece to rotate and a line scanning camera,
the bearing platform is arranged on the base,
the rotary driving mechanism is arranged on the bearing platform,
the line scan camera is used for acquiring a cylindrical image of the workpiece,
the calibration device consists of the calibration device of the line scanning mechanism for the cylindrical visual target, which is described in any one of claims 1 to 2.
4. A cylindrical visual target acquisition device according to claim 3, characterized in that:
wherein the rotation driving mechanism comprises a motor and a plurality of rollers which are arranged on the bearing platform side by side,
the motor is used for driving the roller to rotate.
5. A cylindrical visual target acquisition device according to claim 3, characterized in that:
wherein the line scanning mechanism further comprises a light source,
the light source is used for supplementing light to the calibration column.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122500251.4U CN216118852U (en) | 2021-10-18 | 2021-10-18 | Cylindrical surface visual target acquisition equipment and calibration device of linear scanning mechanism thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122500251.4U CN216118852U (en) | 2021-10-18 | 2021-10-18 | Cylindrical surface visual target acquisition equipment and calibration device of linear scanning mechanism thereof |
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| Publication Number | Publication Date |
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| CN216118852U true CN216118852U (en) | 2022-03-22 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202122500251.4U Active CN216118852U (en) | 2021-10-18 | 2021-10-18 | Cylindrical surface visual target acquisition equipment and calibration device of linear scanning mechanism thereof |
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| CN (1) | CN216118852U (en) |
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- 2021-10-18 CN CN202122500251.4U patent/CN216118852U/en active Active
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