CN215264873U - Camera calibration device and system - Google Patents

Abstract

The application provides a camera calibration device and a system, relates to the technical field of camera calibration and is used for solving the technical problem of low accuracy of a calibration result; the two ends of the calibration plate are respectively provided with a clamping groove matched with the two driving wheels on the robot chassis, and the side wall of each clamping groove far away from the center of the calibration plate is a reference surface; the adjusting mechanism is positioned on the calibration plate, the calibration pattern is positioned on the adjusting mechanism, and the projection of the center of the calibration pattern on the calibration plate is superposed with the center of the calibration plate; the adjusting mechanism comprises two push rods which are respectively used for pushing the driving wheels, and when the push rods push the driving wheels to be abutted against the corresponding reference surfaces, the centers of the calibration patterns are superposed with the symmetric centers of the two driving wheels. The camera calibration system comprises the camera calibration device. The method and the device are used for improving the accuracy of the calibration result.

Description

Camera calibration device and system

Technical Field

The application relates to the technical field of camera calibration, in particular to a camera calibration device and system.

Background

The camera calibration is a basic link of machine vision application such as vision measurement, three-dimensional reconstruction and the like, and the accuracy and precision of the calibration result directly determine whether the vision system can work normally. The camera calibration refers to a process of shooting a calibration image on a calibration plate by a camera, and resolving camera parameters by using three-dimensional coordinates of known feature points in the calibration plate and corresponding image coordinates on the image, wherein the camera calibration comprises camera calibration data acquisition and camera parameter calculation. However, in the related art, the accuracy of the camera calibration result is low.

SUMMERY OF THE UTILITY MODEL

In view of the foregoing problems, embodiments of the present application provide a camera calibration device and a camera calibration system, where the camera calibration device is used to adjust a relative position between a camera to be calibrated and a calibration pattern, so as to accurately position the camera to be calibrated and the calibration pattern, and improve accuracy of a camera calibration result.

In order to achieve the above object, the embodiments of the present application provide the following technical solutions:

a first aspect of the embodiments of the present application provides a camera calibration apparatus, which is used for performing camera calibration on a camera to be calibrated, which is located at a symmetric center of two driving wheels on a chassis of a robot, and includes: the calibration plate, the calibration pattern and the adjusting mechanism; two ends of the calibration plate are respectively provided with a clamping groove matched with the two driving wheels, and the side wall of each clamping groove far away from the center of the calibration plate is a reference surface; the adjusting mechanism is positioned on the calibration plate, the calibration pattern is positioned on the adjusting mechanism, and the projection of the center of the calibration pattern on the calibration plate is superposed with the center of the calibration plate; the adjusting mechanism comprises two push rods which are used for pushing the two driving wheels respectively, and when the push rods push the driving wheels positioned in the clamping grooves to be abutted against the corresponding reference surfaces, the centers of the calibration patterns are superposed with the symmetric centers of the two driving wheels.

In an optional implementation manner, a plurality of guide blocks are arranged on the calibration plate, the guide blocks are arranged at intervals along a first direction, a first guide hole is formed in each guide block, and the push rod is arranged in each first guide hole in a penetrating manner and can move relative to the first guide hole.

In an alternative embodiment, the adjusting mechanism further includes a driving assembly, and the driving assembly is connected to an end of each of the push rods away from the driving wheel, so that the driving assembly drives the push rods to move towards a direction close to or away from the driving wheel.

In an alternative embodiment, the drive assembly includes a follower block, two links, a wedge block, and a source, the driving piece is connected with the wedge-shaped block, the wedge-shaped block is abutted against the follow-up block, the follow-up block is arranged on a symmetrical center line of the calibration plate along a first direction and is in sliding connection with the calibration plate, the two connecting rods are symmetrically arranged on two sides of the follow-up block, one end of each of the two connecting rods is pivoted with the servo block, the other end of each of the two connecting rods is respectively connected with the push rod, when the driving piece drives the wedge-shaped block to move along the first direction, the wedge-shaped block pushes the follow-up block to move towards the center of the calibration plate along the second direction, so that the connecting rod pushes the driving wheel to abut against the reference surface through the push rod, wherein the first direction and the second direction are vertical in a horizontal plane.

In an optional implementation manner, a guide inclined plane is disposed on one side of the wedge block facing the follower block, and when the source drives the wedge block to move along the first direction, the guide inclined plane abuts against the follower block and slides relative to the follower block so as to push the follower block to move along the second direction toward the center of the calibration plate.

In an optional embodiment, a side of the wedge block facing the follower block is further provided with a notch communicated with the guide inclined surface, and when the driving member does not provide driving force to the wedge block, the follower block is clamped in the notch on the wedge block.

In an optional implementation mode, the calibration plate is provided with two first supporting walls arranged at intervals, two second guide holes are formed in the first supporting walls, and the wedge block is arranged in the second guide holes in a penetrating mode and can move relative to the second guide holes.

In an alternative embodiment, a first sliding block is arranged at one end of each push rod away from the driving wheel, and one end of each connecting rod towards the driving wheel is pivoted with the first sliding block.

In an alternative embodiment, the driving member is a pull rod, and one end of the pull rod is connected with the wedge block.

In an optional implementation manner, at least two second support walls are arranged on the calibration plate at intervals, a third guide hole is arranged on each second support wall, and the pull rod is arranged in each third guide hole in a penetrating manner and can move relative to the third guide hole.

In an alternative embodiment, a handle is provided at an end of the pull rod remote from the wedge-shaped block.

In an alternative embodiment, the driving member is a driving motor, and the driving motor drives the wedge block to move along the first direction.

In an optional implementation manner, the driving assembly further includes a screw rod and a second slider, a threaded hole is formed in the second slider, one end of the screw rod is connected with the driving motor, the other end of the screw rod is in threaded connection with the threaded hole, and the driving motor drives the second slider to move towards the wedge block through the screw rod, so that the second slider abuts against and pushes the wedge block to move along the first direction.

In an optional implementation manner, a U-shaped plate is further arranged on the calibration plate, the U-shaped plate includes a first connecting plate, a second connecting plate and a bearing plate, the bearing plate is horizontally arranged, the first connecting plate is vertically arranged at one end of the bearing plate, the second connecting plate is vertically arranged at the other end of the bearing plate, the first connecting plate is abutted against one side of the driving motor facing the wedge block, and an avoiding hole for avoiding the screw rod is arranged on the first connecting plate, so that the screw rod passes through the avoiding hole and is in threaded connection with the second slider; the second slider is located just can be relative on the loading board slides along first direction, be equipped with on the second connecting plate and dodge the mouth of dodging of wedge, so that the wedge wears to locate dodge in the mouth with the second slider butt.

In an optional embodiment, a plurality of first guide rods are further disposed between the first connecting plate and the second connecting plate, and a plurality of first through holes through which the first guide rods can pass are disposed on the second slider, so that the screw drives the second slider to slide along the extending direction of the first guide rods.

In an alternative embodiment, the number of the driving assemblies is two, the two driving assemblies are symmetrically arranged on the calibration plate, and the driving parts of the two driving assemblies are different.

In an optional implementation manner, a bracket is arranged on the follower block in each driving assembly, two brackets in the two driving assemblies are symmetrically arranged, a first spring is arranged between the two brackets, and two ends of the first spring are respectively abutted against end faces of the two brackets, which are oppositely arranged.

In an optional implementation manner, the adjusting mechanism further includes a second guide rod, two ends of the second guide rod are respectively connected to the brackets, an avoidance space for avoiding the second guide rod is provided on each of the brackets, and the first spring is sleeved on the second guide rod so that the brackets can slide along the extending direction of the second guide rod.

In an optional embodiment, at least one second spring is arranged between two first sliding blocks in the two driving assemblies, and two ends of the second spring are respectively abutted against end faces of the two first sliding blocks.

In an optional implementation manner, the adjusting mechanism further includes two supporting blocks and at least two third guiding rods, the two supporting blocks are respectively disposed between the two first sliding blocks and the corresponding driving wheels, a preset gap is disposed between the first sliding block and the supporting block, two ends of the third guiding rod are respectively connected to the two supporting blocks, a third through hole through which the third guiding rod can penetrate is disposed on the first sliding block, so that the first sliding block can slide relative to the third guiding rod, and the second spring is sleeved on the third guiding rod and located between the two first sliding blocks.

In an alternative embodiment, the calibration pattern is located on both of the supports.

In an optional embodiment, the camera calibration device further includes a mounting plate, the mounting plate is mounted on two of the brackets, a central area is provided on the mounting plate, and the calibration pattern is provided on the central area.

In an optional implementation manner, a limiting block is arranged at the symmetrical center of the top of each bracket, a limiting groove is arranged at a position on the mounting plate corresponding to the limiting block, and the limiting block is clamped in the limiting groove.

In an optional implementation manner, two sides of the mounting plate along the first direction are respectively provided with symmetrically arranged limiting rods, two of the supporting blocks are provided with fourth through holes, and the limiting rods penetrate through the fourth through holes and can move relative to the fourth through holes.

In an optional implementation manner, the camera calibration device further includes two detection assemblies, each detection assembly includes a support plate, and a positioning shaft and a pointer are arranged on the support plate; a graduated scale is arranged on one side wall of each clamping groove; when the two detection assemblies are respectively arranged on the driving wheels corresponding to the two detection assemblies, the central line of the positioning shaft is superposed with the central line of the driving wheels, and the pointer is positioned above the graduated scale corresponding to the pointer and points to the graduated scale under the action of gravity.

Compared with the related art, the camera calibration device provided by the embodiment of the application has the following advantages:

the camera calibration device provided by the embodiment of the application, through setting up the calibration pattern on the guiding mechanism on the calibration board, and the center of calibration pattern on the calibration board coincides with the center of calibration board, push away the drive wheel through the push rod among the guiding mechanism, so that the reference surface butt in the draw-in groove of drive wheel and holding drive wheel, so that the center of calibration pattern and the center of symmetry coincidence of two drive wheels, and treat that the calibration camera is located the center of symmetry department of two drive wheels, thereby make to treat that calibration camera and calibration pattern can accurate positioning on the first direction, the accuracy and the accuracy of camera calibration result have been improved, and then avoid leading to the navigation route of robot skew because of the error of calibration result or even the risk of striking goods shelves.

A second aspect of the embodiments of the present application provides a camera calibration apparatus and a camera calibration system, which include the camera calibration apparatus described in the first aspect.

In addition to the technical problems solved by the embodiments of the present application, the technical features constituting the technical solutions, and the advantages brought by the technical features of the technical solutions described above, other technical problems that can be solved by the camera calibration apparatus and system provided by the embodiments of the present application, other technical features included in the technical solutions, and advantages brought by the technical features will be further described in detail in the detailed description.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative efforts.

Fig. 1 is a schematic view illustrating a structure of a view angle of a camera calibration apparatus according to an embodiment of the present disclosure;

FIG. 2 is a top view of FIG. 1;

fig. 3 is a schematic partial structural diagram of a view angle of a camera calibration apparatus according to an embodiment of the present disclosure;

FIG. 4 is an enlarged view of a portion of FIG. 1 at A;

FIG. 5 is an enlarged view of a portion of FIG. 3 at B;

fig. 6 is a schematic structural diagram of another view angle of the camera calibration apparatus according to the embodiment of the present application;

fig. 7 is a schematic diagram of a camera calibration apparatus provided in an embodiment of the present application after a partial structure is exploded;

FIG. 8 is an enlarged view of a portion of FIG. 7 at C;

fig. 9 is a partial structural schematic view of another structure of a camera calibration device provided in an embodiment of the present application;

FIG. 10 is an enlarged view of a portion of FIG. 9 at D;

fig. 11 is a use state diagram of the camera calibration device provided in the embodiment of the present application for performing camera calibration on two driving wheels on a chassis of a robot.

Reference numerals:

100-camera calibration means; 1-calibrating a plate; 11-a card slot; 12-a guide block; 13-a first support wall;

14-a second support wall; 15-U-shaped plate; 2-an adjusting mechanism; 22-a push rod;

23-a drive assembly; 231-a follower block; 232-connecting rod; 233-wedge block; 2331-a guide ramp;

2332-a notch; 24-a first slider; 25-a pull rod; 251-a handle; 26-a drive motor;

27-a screw; 28-a second slide; 29-a first guide bar; 3-a scaffold; 31-a limiting block;

4-a first spring; 5-a second guide bar; 6-a second spring; 7-a third guide bar; 8-a support block;

9-mounting a plate; 91-a limiting groove; 92-a limiting rod; 101-calibrating the pattern; 102-a scale;

103-a detection component; 1031-support plate; 1032-positioning the shaft; 1033-a pointer;

104-a camera to be calibrated; 200-a robot chassis; 201-driving wheel.

Detailed Description

As described in the background art, the camera calibration device in the related art has a problem of low accuracy of the calibration result, and the inventor finds that the reason for the problem is that: the calibration device comprises a calibration plate, calibration patterns are arranged at the center of the calibration plate, clamping grooves matched with two driving wheels on a robot chassis are formed in the two ends of the calibration plate, a camera to be calibrated is located at the symmetrical center of the two driving wheels, the camera is calibrated when the driving wheels are respectively located in the corresponding clamping grooves, however, in order to facilitate the driving wheels to enter and exit the clamping grooves, a gap is formed between the side walls of the driving wheels and the clamping grooves, installation errors exist when the driving wheels and the clamping grooves are installed due to the gap, the driving wheels are not located at the centering positions of the clamping grooves in the clamping grooves, and therefore the positions of the camera to be calibrated and the calibration patterns on the calibration plate, which are located at the symmetrical center line of the driving wheels, are deviated, and the accuracy of camera calibration results is low.

Through repeated thinking and verification, the inventor of the application finds that if a positioning reference surface can be set in the clamping groove, and when the two driving wheels are respectively abutted to the reference surfaces in the corresponding clamping grooves, the camera to be calibrated and the calibration pattern can be accurately positioned, so that the accuracy and the precision of the calibration result are improved.

In view of this, the embodiment of the present application provides a camera calibration device and a camera calibration system, in the camera calibration device, a calibration pattern is disposed on an adjusting mechanism on a calibration plate, and a center of the calibration pattern on the calibration plate coincides with a center of the calibration plate, a push rod in the adjusting mechanism pushes against a driving wheel, so that the driving wheel abuts against a reference surface in a slot accommodating the driving wheel, so that the center of the calibration pattern coincides with symmetric centers of two driving wheels, and a camera to be calibrated is located at the symmetric centers of the two driving wheels, so that the camera to be calibrated and the calibration pattern can be accurately positioned in a first direction, accuracy and precision of a camera calibration result are improved, and further, a risk that a navigation route of a robot deviates even hits a goods shelf due to a large error of the calibration result is avoided.

In order to make the aforementioned objects, features and advantages of the embodiments of the present application more comprehensible, embodiments of the present application are described in detail below with reference to the accompanying drawings. It is to be understood that the described embodiments are merely a few embodiments of the present application and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

Fig. 1 is a schematic view illustrating a structure of a view angle of a camera calibration apparatus according to an embodiment of the present disclosure; fig. 2 is a top view of fig. 1.

Referring to fig. 1 and fig. 2, a camera calibration apparatus 100 provided in an embodiment of the present application is used for calibrating a camera 104 to be calibrated, which is located at a symmetric center of two driving wheels 201 on a robot chassis 200, and includes: the calibration plate 1, the calibration pattern 101 and the adjusting mechanism 2; two ends of the calibration plate 1 are respectively provided with a clamping groove 11 matched with the two driving wheels 201, and the side wall of each clamping groove 11 far away from the center of the calibration plate 1 is a reference surface; the adjusting mechanism 2 is positioned on the calibration plate 1, the calibration pattern 101 is positioned on the adjusting mechanism 2, and the projection of the center of the calibration pattern 101 on the calibration plate 1 is superposed with the center of the calibration plate 1; the adjusting mechanism 2 includes two push rods 22 for pushing against the two driving wheels 201, and when the push rods 22 push against the driving wheels 201 in the card slot 11 to abut against the corresponding reference surfaces, the center of the calibration pattern 101 coincides with the symmetric centers of the two driving wheels 201.

By arranging the camera 104 to be calibrated on the robot chassis 200 at the symmetrical center of the two driving wheels 201, arranging the calibration pattern 101 on the adjusting mechanism 2 on the calibration plate 1, and the center of the calibration pattern 101 on the calibration plate 1 coincides with the center of the calibration plate 1, the driving wheel 201 is pushed by the push rod 22 of the adjusting mechanism 2, so that the driving wheel 201 is abutted with the reference surface of the card slot 11 for accommodating the driving wheel 201, and thus, by adjusting the position of the driving wheel 201 in the first direction, the adjustment of the position of the robot chassis 200 in the first direction is achieved, so that the center of the calibration pattern 101 coincides with the symmetric centers of the two driving wheels 201, and the camera 104 to be calibrated and the calibration pattern 101 can be precisely positioned in the first direction, thereby improving the accuracy and precision of the calibration result, further, the risk that the navigation route of the robot deviates and even the robot collides with a goods shelf due to large error of the calibration result is avoided.

Wherein the first direction coincides with the direction of the centre of rotation axis of the two drive wheels 201.

It can be understood that two push rods 22 are symmetrically arranged in the adjusting mechanism 2, one push rod 22 corresponds to one driving wheel 201, and when two driving wheels 201 are respectively located in the corresponding card slots 11, the push rod 22 pushes the driving wheel 201 to move towards the center far away from the calibration board 1, so that the driving wheel 201 is abutted to the reference surface in the card slot 11.

The reference surface can be a reference surface with certain precision machined by grinding and other modes on the side wall of the clamping groove 11 far away from the center of the calibration plate 1; alternatively, a reference surface with a certain precision may be attached to the side wall of the card slot 11, as long as the reference surface can be abutted by the driving wheels 201, so that the camera 104 to be calibrated located at the symmetric center of the two driving wheels 201 and the calibration pattern 101 can be accurately positioned, which is not limited in this embodiment.

In order to improve the accuracy of the movement of the push rod 22 towards the driving wheel 201 and avoid the deviation of the push rod 22 when moving, in this embodiment, the calibration plate 1 is provided with a plurality of guide blocks 12, the plurality of guide blocks 12 are arranged at intervals along the first direction, each guide block 12 is provided with a first guide hole, and the push rod 22 is inserted into each first guide hole and can move relative to the first guide hole, so that the accuracy of the movement of the push rod 22 along the first direction can be improved. Wherein the first direction coincides with the direction of the centre of rotation axis of the two drive wheels 201.

Fig. 3 is a schematic partial structural diagram of a view angle of a camera calibration apparatus according to an embodiment of the present disclosure; FIG. 4 is an enlarged view of a portion of FIG. 1 at A; fig. 5 is a partially enlarged view of fig. 3 at B.

Referring to fig. 3 to 5, the adjusting mechanism 2 further includes a driving assembly 23, and the driving assembly 23 is connected to an end of each of the push rods 22 away from the driving wheel 201, so that the driving assembly 23 drives the push rods 22 to move toward or away from the driving wheel 201.

In the present application, the driving assembly 23 includes a follower block 231, two connecting rods 232, a wedge block 233 and a source, the source is connected to the wedge block 233, the wedge block 233 abuts against the follower block 231, the follower block 231 is disposed on a symmetry center line of the calibration board 1 along the first direction and is slidably connected to the calibration board 1, the two connecting rods 232 are symmetrically disposed on two sides of the follower block 231, and one end of each of the two connecting rods 232 is pivotally connected to the follower block 231, the other end of each of the two connecting rods 232 is connected to the push rod 22, when the source drives the wedge block 233 to move along the first direction, the wedge block 233 abuts against the follower block 231 to move along the second direction toward the center of the calibration board 1, so that the connecting rods 232 push the driving wheel 201 to abut against the reference surface through the push rod 22, wherein the first direction and the second direction are perpendicular to the horizontal plane.

In a specific implementation, the driving element provides a driving force to the wedge block 233, the wedge block 233 is driven to push the follower block 231 to move towards the center of the calibration board 1 along the second direction, and because one end of each of the two connecting rods 232 is pivoted with the follower block 231, when the follower block 231 moves towards the center of the calibration board 1 along the second direction, the connecting rod 232 rotates relative to the follower block 231 and applies a component force towards the driving wheel 201 to the push rod 22, so that the push rod 22 pushes the driving wheel 201 to abut against a corresponding reference surface, and the camera 104 to be calibrated and the calibration pattern 101 can be accurately positioned in the first direction, thereby improving the accuracy and precision of the calibration result, and avoiding the risk that a robot deviates a navigation route and even hits a shelf or other devices in the storage space due to a large error of the calibration result.

The profile surface of the follower block 231 on the side abutting against the wedge block 233 may be an arc profile surface, for example, an arc profile surface.

The wedge block 233 is provided with a guide inclined surface 2331 on a side facing the follower block 231, and when the driver drives the wedge block 233 to move along the first direction, the guide inclined surface 2331 abuts against the follower block 231 and slides relative to the follower block 231 to push the follower block 231 to move along the second direction toward the center of the calibration plate 1.

Specifically, by arranging the guide inclined plane 2331 on the side of the wedge block 233 facing the follower block 231, because the guide inclined plane 2331 forms an inclined included angle with the first direction, when the driving member drives the wedge block 233 to move along the first direction, the guide inclined plane 2331 can push the follower block 231 to move along the second direction toward the center of the calibration plate 1, so that the connecting rod 232 on the follower block 231 drives the push rod 22 to push the driving wheel 201 along the first direction, so as to adjust the relative position between the camera 104 to be calibrated and the calibration pattern 101 through the adjusting mechanism 2.

In addition, a notch 2332 communicated with the guide inclined surface 2331 is further arranged on one side of the wedge block 233 facing the follower block 231, and when the driving element does not provide driving force to the wedge block 233, the follower block 231 is clamped in the notch 2332 on the wedge block 233, so that when the relative position between the camera 104 to be calibrated and the calibration pattern 101 does not need to be adjusted, the relative position between the follower block 231 and the wedge block 233 can be improved, and the phenomenon that the follower block 231 and the wedge block 233 are dislocated due to factors such as external impact on the camera calibration device 100 is avoided, and the adjustment precision of the adjustment mechanism 2 is further influenced.

On the basis of the above embodiment, the calibration plate 1 is provided with the first support walls 13 arranged at two intervals, the two first support walls 13 are provided with the second guide holes, and the wedge block 233 penetrates through the second guide holes and can move relative to the second guide holes, so that the accuracy of the moving route of the wedge block 233 can be improved.

In addition, a first slider 24 is disposed at one end of each push rod 22 away from the driving wheel 201, and one end of each link 232 facing the driving wheel 201 is pivotally connected to the first slider 24.

Through setting up first slider 24, can improve the connection reliability between connecting rod 232 and the push rod 22, connecting rod 232 supports through first slider 24 and pushes away push rod 22 and move towards drive wheel 201 to make push rod 22 and drive wheel 201 butt, and make drive wheel 201 and the reference surface butt in the draw-in groove 11, treat the adjustment of the position between camera 104 and the calibration pattern 101 of maring, realize waiting to calibrate accurate positioning on the first direction between camera 104 and the calibration pattern 101, thereby improve the accuracy and the accuracy of calibration result.

The first slider 24 may be a rectangular parallelepiped, a cube, or the like.

Fig. 6 is a schematic structural diagram of another view angle of the camera calibration apparatus according to the embodiment of the present application;

fig. 7 is an exploded schematic view of a partial structure of a camera calibration device according to an embodiment of the present application.

Referring to fig. 6 and 7, in some alternative embodiments, the driving element is a pull rod 25, one end of the pull rod 25 is connected to a wedge block 233, and when adjusting the relative position between the camera 104 to be calibrated and the calibration pattern 101, first, the pull rod 25 is pushed, the pull rod 25 pushes the wedge block 233 to move along a first direction, the wedge block 233 pushes the follower block 231 to move along a second direction toward the center of the calibration board 1, and the follower block 231 drives the connecting rod 232, so that the connecting rod 232 pushes the push rod 22 through the first slider 24 to move along the first direction toward the driving wheel 201, so that the push rod 22 pushes the driving wheel 201 to abut against the reference surface.

The tie rod 25 may be a rod-shaped structure having a cross section of any shape such as a circle, a rectangle, an ellipse, etc. and extending along a predetermined path.

The calibration plate 1 is provided with at least two second support walls 14 arranged at intervals, each second support wall 14 is provided with a third guide hole, and the pull rod 25 penetrates through each third guide hole and can move relative to the third guide hole, so that the accuracy of the moving route of the pull rod 25 is improved.

In addition, the handle 251 is arranged at one end, far away from the wedge block 233, of the pull rod 25, so that when a user pushes and pulls the pull rod 25, the user can push and pull the pull rod by holding the handle 251, using comfort of the user is improved, and body feeling of the user is improved.

With continued reference to fig. 4 and 5, in alternative embodiments, the driving element is a driving motor 26, and the driving motor 26 drives the wedge 233 to move in the first direction, which can save labor and improve working efficiency.

On this basis, the driving assembly 23 further includes a screw 27 and a second slider 28, the second slider 28 is provided with a threaded hole, one end of the screw 27 is connected with the driving motor 26, the other end of the screw 27 is in threaded connection with the threaded hole, the driving motor 26 drives the second slider 28 to move towards the wedge block 233 through the screw 27, so that the second slider 28 pushes the wedge block 233 to move along the first direction.

Specifically, the driving motor 26 drives the screw 27 to rotate, so that the screw 27 and the second slider 28 are in screw transmission, and the second sliding slot pushes the wedge 233 to move along the first direction.

The calibration plate 1 is further provided with a U-shaped plate 15, the U-shaped plate 15 comprises a first connecting plate, a second connecting plate and a bearing plate, the bearing plate is horizontally arranged, the first connecting plate is vertically arranged at one end of the bearing plate, the second connecting plate is vertically arranged at the other end of the bearing plate, the first connecting plate is abutted against one side, facing the wedge block 233, of the driving motor 26, and the first connecting plate is provided with an avoidance hole for avoiding the screw 27 so that the screw 27 penetrates through the avoidance hole to be in threaded connection with the second slider 28; the second slider 28 is located on the bearing plate and can slide along the first direction relative to the bearing plate, and an avoiding opening for avoiding the wedge 233 is formed in the second connecting plate, so that the wedge 233 penetrates through the avoiding opening to be abutted against the second slider 28.

In addition, a plurality of first guide rods 29 are arranged between the first connecting plate and the second connecting plate, and a plurality of first through holes for the first guide rods 29 to pass through are arranged on the second sliding block 28, so that the screw 27 drives the second sliding block 28 to slide along the extending direction of the first guide rods 29.

It can be understood that one end of the plurality of first guide rods 29 is fixedly connected to the first connecting plate, and the other end of the plurality of first guide rods 29 is fixedly connected to the second connecting plate, so that the second slider 28 is driven by the screw 27 to move on the bearing plate, thereby causing the second slider 28 to push the wedge 233 to move in the first direction.

In order to be suitable for different applications, with continued reference to fig. 4 and 5, in the present embodiment, there are two driving assemblies 23, two driving assemblies 23 are symmetrically arranged on the calibration board 1, and the driving members in the two driving assemblies 23 are different.

It can be understood that, when there are two driving assemblies 23, and the two driving assemblies 23 are symmetrically disposed on the calibration board 1, such that the connecting rods 232 in the two driving assemblies 23 form a parallelogram or a rhombus, wherein the driving member in one driving assembly 23 can be the pull rod 25, and the driving member in the other driving assembly 23 can be the driving motor 26, so that the driving by the pull rod 25 or the driving motor 26 can be selected according to the requirement, for example, the driving by the pull rod 25 can be selected for fine adjustment, and vice versa, the driving by the driving motor 26 can be selected; still alternatively, the driving by the pull rod 25 can be adapted to the condition without power supply, thereby increasing the applicable range of the camera calibration apparatus 100.

Be equipped with support 3 on the follower block 231 in each drive assembly 23, two supports 3 symmetry settings in two drive assemblies 23, and be equipped with first spring 4 between two supports 3, the terminal surface butt that the both ends of first spring 4 set up with two supports 3 are relative respectively.

By arranging the first spring 4 between the two brackets 3, when the driving element does not provide driving force, the elastic force of the first spring 4 can push the brackets 3, so that the brackets 3 drive the follower block 231 to move towards the wedge block 233 along the second direction, and thus the pull rod 25 can pull the push rod 22 to move towards the center of the calibration plate 1, so that the push rod 22 and the driving wheel 201 are released from abutting, wherein the first spring 4 can be a cylindrical compression spring or the like.

Further, in order to improve the accuracy of the moving route of the first spring 4 under the action of the elastic force of the first spring, in this embodiment, the adjusting mechanism 2 further includes a second guide rod 5, two ends of the second guide rod 5 are respectively connected with the supports 3, each support 3 is provided with an avoidance space for avoiding the second guide rod 5, and the first spring 4 is sleeved on the second guide rod 5, so that the supports 3 can slide along the extending direction of the second guide rod 5, and the moving route of the first spring 4 is prevented from deviating when moving under the action of the elastic force of the first spring 4.

In addition to the above-described embodiments, at least one second spring 6 is provided between the two first sliders 24 in the two driving assemblies 23, and both ends of the second spring 6 are respectively abutted to the end surfaces of the two first sliders 24.

In a specific implementation, when the two push rods 22 are in a retracted state, that is, when the push rods 22 do not push against the driving wheel 201, the second spring 6 is located between the two first sliders 24 and is in a compressed state, and when the driving element drives the follower block 231 to move toward the center of the calibration plate 1 along the second direction through the wedge block 233, the link 232 provides a pushing force to the push rods 22 through the first sliders 24, and at the same time, the elastic force of the second spring 6 also pushes the first sliders 24, so that the first sliders 24 push the push rods 22 to move toward the driving wheel 201, thereby increasing the pushing force provided by the push rods 22 to the driving wheel 201, so that the driving wheel 201 abuts against the reference surface, and the camera 104 to be calibrated and the calibration pattern 101 are accurately positioned in the first direction.

Furthermore, the adjusting mechanism 2 further includes two supporting blocks 8 and at least two third guide bars 7, the two supporting blocks 8 are respectively disposed between the two first sliders 24 and the corresponding driving wheels 201, a preset gap is disposed between the first slider 24 and the supporting blocks 8, two ends of the third guide bar 7 are respectively connected with the two supporting blocks 8, and a third through hole through which the third guide bar 7 can penetrate is disposed on the first slider 24, so that the first slider 24 can slide relative to the third guide bar 7, and the second spring 6 is sleeved on the third guide bar 7 and located between the two first sliders 24, so that accuracy of movement of the first slider 24 along the first direction can be improved, and deviation during movement is avoided.

It should be noted that the preset gap between the first slider 24 and the supporting block 8 refers to a gap between the position of the first slider 24 and the supporting block 8 when the push rod 22 is in the retracted state, wherein the preset gap needs to be larger than the moving distance of the first slider 24 in the first direction, so as to prevent the supporting block 8 from interfering with the movement of the first slider 24 in the first direction. It is understood that the moving distance of the first slider 24 in the first direction refers to: the distance between the position of the first slider 24 when the push rod 22 is in the retracted state and the position of the first slider 24 when the push rod 22 pushes the driving wheel 201 against the reference surface.

Further, the calibration patterns 101 are located on the two supports 3, and the projection of the center of the calibration pattern 101 on the calibration board 1 coincides with the center of the calibration board 1.

Fig. 8 is a partial enlarged view at C in fig. 7.

Referring to fig. 4 and 8, on the basis of the above embodiment, the camera calibration device 100 further includes a mounting plate 9, the mounting plate 9 is mounted on the two brackets 3, the mounting plate 9 is provided with a central area, and the calibration pattern 101 is arranged on the central area.

It can be understood that the calibration pattern 101 is disposed in a central area on the mounting board 9 by means of pasting or the like, and the center of the calibration pattern 101 coincides with the center of the central area, and the projection of the center of the central area on the calibration board 1 coincides with the center of the calibration board 1, so that when the two driving wheels 201 abut against their corresponding reference surfaces respectively, the center of the camera 104 to be calibrated coincides with the center of the calibration pattern 101 in the first direction, thereby improving the accurate positioning between the camera 104 to be calibrated and the calibration pattern 101.

Continuing to refer to fig. 5, the symmetrical center of the top of each bracket 3 is provided with a limiting block 31, a limiting groove 91 is provided at the position of the mounting plate 9 corresponding to the limiting block 31, and the limiting block 31 is clamped in the limiting groove 91.

The limiting block 31 is arranged at the symmetrical center of the top of the support 3, the limiting groove 91 is arranged at the position, corresponding to the limiting block 31, of the mounting plate 9, when the limiting block 31 is clamped in the limiting groove 91, the mounting plate 9 can be positioned in the first direction, and therefore the center of the mounting plate 9 coincides with the center of the calibration plate 1 in the first direction.

Furthermore, two sides of the mounting plate 9 in the first direction are respectively provided with a limiting rod 92 which is symmetrically arranged, the two supporting blocks 8 are provided with fourth through holes, and the limiting rod 92 penetrates through the fourth through hole and can move relative to the fourth through hole.

Like this, when gag lever post 92 was located the fourth through-hole, then can spacing mounting panel 9 in the second direction to make mounting panel 9 coincide with the center of calibration board 1 in the center of second direction, avoid mounting panel 9 dislocation and lead to demarcating the pattern 101 position and take place the dislocation.

Fig. 9 is a partial structural schematic view of another structure of a camera calibration device provided in an embodiment of the present application; FIG. 10 is an enlarged view of a portion of FIG. 9 at D; fig. 11 is a use state diagram of the camera calibration device provided in the embodiment of the present application for performing camera calibration on two driving wheels on a chassis of a robot.

Referring to fig. 9 to 11, the camera calibration apparatus 100 further includes two detecting assemblies 103, each detecting assembly 103 includes a supporting plate 1031, and a positioning shaft 1032 and a pointer 1033 are disposed on the supporting plate 1031; a graduated scale 102 is arranged on one side wall of each clamping groove 11; when the two detection assemblies 103 are respectively mounted on the driving wheels 201 corresponding to the two detection assemblies, the center line of the positioning shaft 1032 coincides with the center line of the driving wheel 201, and the pointer 1033 is located above the scale 102 corresponding to the two detection assemblies and points to the scale 102 under the action of gravity.

By arranging two detection assemblies 103, when the camera is calibrated, the robot chassis 200 is placed on the calibration board 1, and the two detection assemblies 103 are respectively installed on the driving wheels 201 corresponding to the two detection assemblies 103, namely, one detection assembly 103 corresponds to one driving wheel 201, so that the central line of the positioning shaft 1032 in the detection assembly 103 is coincided with the central line of the driving wheel 201, the pointer 1033 in the detection assembly 103 points to the scale 102 on one side wall of the card slot 11 under the action of gravity, the deviation between the driving wheel 201 and the card slot 11 in the second direction is judged according to the position pointed by the pointer 1033 on the scale 102, so as to judge the deviation value between the camera to be calibrated and the calibration pattern in the second direction, and therefore, the robot chassis 200 is adjusted according to the deviation value, so that the driving wheel 201 is located at the centering position of the card slot 11 in the second direction, so as to accurately position the camera 104 to be calibrated and the calibration pattern 101 in the second direction, therefore, the accuracy of the calibration result is improved, and the risk that the robot navigation route deviates and even collides with a goods shelf due to large error of the calibration result is avoided.

The embodiment of the present application further provides a camera calibration system, which includes the camera calibration device 100 provided in the above embodiment.

The structure and the operation principle of the camera calibration device 100 have been described in detail in the above embodiments, and are not described in detail herein.

The camera calibration system provided by the embodiment of the application comprises a camera calibration device, wherein, in the camera calibration device, the calibration pattern is arranged on an adjusting mechanism on a calibration plate, the center of the calibration pattern on the calibration plate coincides with the center of the calibration plate, a push rod in the adjusting mechanism pushes against a driving wheel, so that the driving wheel abuts against a reference surface in a clamping groove for accommodating the driving wheel, the center of the calibration pattern coincides with the symmetric centers of two driving wheels, the camera to be calibrated and the calibration pattern can be accurately positioned, the accuracy and precision of the calibration result of the camera can be improved, and the risk that a navigation route of a robot deviates and even hits a goods shelf due to the large error of the calibration result is avoided.

The embodiments or implementation modes in the present specification are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments may be referred to each other.

In the description herein, references to the description of the terms "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like mean 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 embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Finally, it should be noted that: the above embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present application.

Claims (26)

1. A camera calibration device is used for calibrating a camera to be calibrated, which is positioned at the symmetrical center of two driving wheels on a robot chassis, and is characterized by comprising the following components: the calibration plate, the calibration pattern and the adjusting mechanism; two ends of the calibration plate are respectively provided with a clamping groove matched with the two driving wheels, and the side wall of each clamping groove far away from the center of the calibration plate is a reference surface;

the adjusting mechanism is positioned on the calibration plate, the calibration pattern is positioned on the adjusting mechanism, and the projection of the center of the calibration pattern on the calibration plate is superposed with the center of the calibration plate; the adjusting mechanism comprises two push rods which are used for pushing the two driving wheels respectively, and when the push rods push the driving wheels positioned in the clamping grooves to be abutted against the corresponding reference surfaces, the centers of the calibration patterns are superposed with the symmetric centers of the two driving wheels.

2. The camera calibration device according to claim 1, wherein a plurality of guide blocks are disposed on the calibration plate, the guide blocks are disposed at intervals along a first direction, a first guide hole is disposed on each guide block, and the push rod is inserted into each first guide hole and can move relative to the first guide hole.

3. The camera calibration device according to claim 2, wherein the adjustment mechanism further comprises a driving assembly, and the driving assembly is connected to an end of each of the push rods away from the driving wheel, so that the driving assembly drives the push rods to move toward or away from the driving wheel.

4. The camera calibration device according to claim 3, wherein the driving assembly includes a follower block, two connecting rods, a wedge block and a source, the source is connected to the wedge block, the wedge block abuts against the follower block, the follower block is disposed on a center line of symmetry of the calibration board along a first direction and slidably connected to the calibration board, the two connecting rods are symmetrically disposed on two sides of the follower block, and one end of each of the two connecting rods is pivotally connected to the follower block, the other end of each of the two connecting rods is connected to the push rod, when the source drives the wedge block to move along the first direction, the wedge block abuts against the follower block to move along a second direction toward the center of the calibration board, so that the connecting rods abut against the driving wheel through the push rods to abut against the reference surface, the first direction and the second direction are perpendicular in a horizontal plane.

5. The camera calibration device according to claim 4, wherein a side of the wedge block facing the follower block is provided with a guide inclined surface, and when the wedge block is driven by the driving element to move along a first direction, the guide inclined surface abuts against the follower block and slides relative to the follower block so as to push the follower block to move along a second direction toward the center of the calibration plate.

6. A camera calibration device according to claim 5, wherein a notch communicated with the guide inclined plane is further formed in one side of the wedge block facing the follower block, and when the driving member does not provide driving force to the wedge block, the follower block is clamped in the notch formed in the wedge block.

7. The camera calibration device according to any one of claims 4 to 6, wherein two first support walls are disposed on the calibration plate at intervals, second guide holes are disposed on both of the two first support walls, and the wedge block is disposed through the second guide holes and can move relative to the second guide holes.

8. A camera calibration device according to any one of claims 4 to 6, wherein a first slider is disposed at an end of each push rod away from the driving wheel, and an end of each link rod facing the driving wheel is pivotally connected to the first slider.

9. A camera calibration device according to any one of claims 4 to 6, wherein the source is a pull rod, and one end of the pull rod is connected with the wedge block.

10. The camera calibration device according to claim 9, wherein the calibration plate is provided with at least two second support walls arranged at intervals, each second support wall is provided with a third guide hole, and the pull rod is inserted into each third guide hole and can move relative to the third guide hole.

11. The camera calibration device according to claim 10, wherein a handle is provided at an end of the pull rod away from the wedge block.

12. The camera calibration device according to any one of claims 4 to 6, wherein the source is a driving motor, and the driving motor drives the wedge block to move along the first direction.

13. The camera calibration device according to claim 12, wherein the driving assembly further includes a screw and a second slider, a threaded hole is formed in the second slider, one end of the screw is connected to the driving motor, the other end of the screw is in threaded connection with the threaded hole, and the driving motor drives the second slider to move toward the wedge block through the screw, so that the second slider pushes the wedge block to move along the first direction.

14. The camera calibration device according to claim 13, wherein a U-shaped plate is further disposed on the calibration plate, the U-shaped plate includes a first connecting plate, a second connecting plate, and a bearing plate, the bearing plate is horizontally disposed, the first connecting plate is vertically disposed at one end of the bearing plate, the second connecting plate is vertically disposed at the other end of the bearing plate, the first connecting plate abuts against one side of the driving motor facing the wedge, and an avoiding hole for avoiding the screw rod is disposed on the first connecting plate, so that the screw rod passes through the avoiding hole and is in threaded connection with the second slider; the second slider is located just can be relative on the loading board slides along first direction, be equipped with on the second connecting plate and dodge the mouth of dodging of wedge, so that the wedge wears to locate dodge in the mouth with the second slider butt.

15. A camera calibration device according to claim 14, wherein a plurality of first guide rods are further disposed between the first connecting plate and the second connecting plate, and a plurality of first through holes for passing through the first guide rods are disposed on the second slider, so that the screw drives the second slider to slide along the extending direction of the first guide rods.

16. The camera calibration device according to claim 8, wherein there are two driving assemblies, the two driving assemblies are symmetrically disposed on the calibration board, and the driving parts of the two driving assemblies are different.

17. A camera calibration device according to claim 16, wherein a bracket is disposed on the follower block in each of the driving assemblies, two brackets of the two driving assemblies are symmetrically disposed, a first spring is disposed between the two brackets, and two ends of the first spring are respectively abutted to end surfaces of the two brackets, which are disposed oppositely.

18. A camera calibration device according to claim 17, wherein the adjustment mechanism further includes a second guide rod, two ends of the second guide rod are respectively connected to the brackets, an avoidance space is provided on each of the brackets to avoid the second guide rod, and the first spring is sleeved on the second guide rod so that the brackets can slide along the extending direction of the second guide rod.

19. A camera calibration device according to claim 18, wherein at least one second spring is disposed between two first sliders in the two driving assemblies, and two ends of the second spring are respectively abutted against end surfaces of the two first sliders.

20. The camera calibration device according to claim 19, wherein the adjustment mechanism further includes two support blocks and at least two third guide rods, the two support blocks are respectively disposed between the two first sliders and the corresponding driving wheels, a predetermined gap is disposed between the first sliders and the support blocks, two ends of the third guide rods are respectively connected to the two support blocks, and a third through hole is disposed on the first slider and through which the third guide rod can pass, so that the first slider can slide relative to the third guide rods, and the second spring is sleeved on the third guide rods and located between the two first sliders.

21. A camera calibration device according to claim 20 wherein the calibration pattern is located on both of the brackets.

22. A camera calibration device according to claim 21, further comprising a mounting plate, wherein the mounting plate is mounted on two of the brackets, a central region is provided on the mounting plate, and the calibration pattern is provided on the central region.

23. The camera calibration device according to claim 22, wherein a limiting block is disposed at a symmetrical center of a top of each of the brackets, a limiting groove is disposed at a position on the mounting plate corresponding to the limiting block, and the limiting block is engaged in the limiting groove.

24. The camera calibration device according to claim 23, wherein two sides of the mounting plate along the first direction are respectively provided with symmetrically arranged limiting rods, the two supporting blocks are provided with fourth through holes, and the limiting rods penetrate through the fourth through holes and can move relative to the fourth through holes.

25. The camera calibration device according to any one of claims 1 to 6, further comprising two detection assemblies, wherein the detection assemblies comprise a support plate, and a positioning shaft and a pointer are arranged on the support plate; a graduated scale is arranged on one side wall of each clamping groove; when the detection assemblies are respectively arranged on the driving wheels corresponding to the detection assemblies, the central line of the positioning shaft is superposed with the central line of the driving wheels, and the pointer is positioned above the graduated scale corresponding to the pointer and points to the graduated scale under the action of gravity.

26. A camera calibration system, comprising the camera calibration apparatus of any one of claims 1 to 25.

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