Robot and laser sensor hand-eye calibration method and device

Abstract

The present invention provides a robot and laser sensor hand-eye calibration method and device, the method comprising: establishing a user coordinate system of the robot based on a calibration plate; moving the robot according to the user coordinate system, obtaining a first point position of the robot tool end when the laser near field of view of the sensor coincides with a specific edge of the calibration plate; obtaining a second point position of the robot tool end when the laser far field of the sensor coincides with a specific edge of the calibration plate; keeping the posture unchanged, moving the robot position, obtaining a third point position of the robot tool end when the robot TCP is aligned with a spatial recognition point; constructing a hand-eye calibration mathematical model of the robot and the laser sensor; determining a calibration matrix between the robot and the laser sensor based on the first point position, the second point position, the third point position and the mathematical model. Only three points need to be determined and a hand-eye calibration mathematical model needs to be constructed to calibrate, thus avoiding errors caused by multiple manual teachings, simplifying the calibration method, and improving the calibration accuracy.

Description

Technical Field

[0001] The present invention relates to the technical field of industrial robots, and in particular to a robot and laser sensor hand-eye calibration method and device. Background Art

[0002] With the booming development of the manufacturing industry, industrial robots have become irreplaceable automation equipment in the manufacturing industry due to their high flexibility and good accessibility. The combination of laser sensors and industrial robots is equivalent to giving robots eyes, enabling them to perceive the external environment. In order for the robot to move according to the position identified by the laser sensor, it is necessary to establish a conversion relationship between the sensor coordinate system and the robot coordinate system.

[0003] The existing hand-eye calibration method has a complex conversion relationship and requires multiple manual teaching of the robot to align the recognition points, which not only causes large calibration errors but also makes the calibration method more complicated. Summary of the invention

[0004] The object of the present invention is to provide a robot and laser sensor hand-eye calibration method and device which can reduce calibration errors and simplify calibration methods.

[0005] To achieve the above object, the present invention provides a robot and laser sensor hand-eye calibration method, which comprises:

[0006] Based on the calibration plate, a user coordinate system of the robot is established by using a three-point method; the calibration plate is placed within the reach of the robot;

[0007] Moving the robot according to the user coordinate system to obtain the first point position of the robot tool end when the laser near field of view of the laser sensor coincides with a specific edge of the calibration plate;

[0008] Moving the robot according to the user coordinate system to obtain a second point position of the robot tool end when the laser far field of view of the laser sensor coincides with a specific edge of the calibration plate;

[0009] Keeping the posture of the robot unchanged, moving the position of the robot, and obtaining the third point position of the end of the robot tool when the robot tool center point TCP is aligned with the spatial identification point on the calibration plate;

[0010] Construct mathematical models for hand-eye calibration of robots and laser sensors;

[0011] Based on the first point, the second point, the third point and the hand-eye calibration mathematical model, a calibration matrix between the robot and the laser sensor is determined.

[0012] The present invention provides a robot and laser sensor hand-eye calibration device, which is used to reduce calibration errors and simplify calibration methods, and includes:

[0013] A first point position acquisition module is used to move the robot according to the user coordinate system to obtain a first point position of the robot tool end when the laser near field of view of the laser sensor coincides with a specific edge of the calibration plate;

[0014] A second point position acquisition module is used to move the robot according to the user coordinate system to obtain a second point position of the robot tool end when the laser far field of view of the laser sensor coincides with a specific edge of the calibration plate;

[0015] A third point position acquisition module is used to keep the posture of the robot unchanged, move the position of the robot, and acquire the third point position of the end of the robot tool when the robot tool center point TCP is aligned with the spatial identification point on the calibration plate;

[0016] Mathematical model building module, used to build the hand-eye calibration mathematical model of the robot and laser sensor;

[0017] A calibration matrix determination module, used to determine a calibration matrix between the robot and the laser sensor based on the first point, the second point, the third point and the hand-eye calibration mathematical model;

[0018] Wherein, the laser sensor is installed on the robot.

[0019] The embodiment of the present invention establishes the user coordinate system of the robot by using the three-point method based on the calibration plate; moves the robot according to the user coordinate system to obtain the first point position of the end of the robot tool when the laser near field of view of the laser sensor coincides with the specific edge of the calibration plate; moves the robot according to the user coordinate system to obtain the second point position of the end of the robot tool when the laser far field of view of the laser sensor coincides with the specific edge of the calibration plate; keeps the posture of the robot unchanged, moves the position of the robot, and obtains the third point position of the end of the robot tool when the center point TCP of the robot tool is aligned with the spatial recognition point on the calibration plate; constructs a hand-eye calibration mathematical model for the robot and the laser sensor; determines the calibration matrix between the robot and the laser sensor based on the first point position, the second point position, the third point position and the hand-eye calibration mathematical model. Only three points need to be determined and the hand-eye calibration mathematical model needs to be constructed to complete the calibration, which avoids the error caused by the manual teaching in the prior art that causes the laser to irradiate the recognition point multiple times, which not only simplifies the calibration method, but also improves the calibration accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The following drawings are intended only to illustrate and explain the present invention, and are not intended to limit the scope of the present invention.

[0021] Figure 1 Schematic diagram of the implementation process of the robot and laser sensor hand-eye calibration method of the embodiment of the present invention;

[0022] Figure 2 is a schematic diagram of the installation and operation of the robot and the laser sensor in an embodiment of the present invention;

[0023] Figure 3 is a side schematic diagram of a calibration plate in an embodiment of the present invention;

[0024] Figure 4 is a schematic diagram of the positional relationship between the user coordinate system of the robot and the calibration plate in an example of the present invention;

[0025] Figure 5 is a schematic diagram of a processing flow of a robot automatic calibration program in an embodiment of the present invention;

[0026] Figure 6 It is a schematic diagram of the structure of a robot and laser sensor hand-eye calibration device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0027] The present application is further described in detail below through the accompanying drawings and embodiments. Through these descriptions, the characteristics and advantages of the present application will become clearer and more specific.

[0028] The word "exemplary" is used exclusively herein to mean "serving as an example, embodiment, or illustration." Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. Although various aspects of the embodiments are shown in the drawings, the drawings are not necessarily drawn to scale unless otherwise noted.

[0029] In addition, the technical features involved in different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0030] The embodiment of the present invention provides a robot and laser sensor hand-eye calibration method to reduce calibration errors and simplify calibration methods. Figure 1 As shown, including:

[0031] Step 101: Based on the calibration plate, a user coordinate system of the robot is established using a three-point method; the calibration plate is placed within the reach of the robot;

[0032] Step 102: Move the robot according to the user coordinate system to obtain the first point position of the robot tool end when the laser near field of view of the laser sensor coincides with a specific edge of the calibration plate;

[0033] Step 103: Move the robot according to the user coordinate system to obtain a second point position of the robot tool end when the laser far field of view of the laser sensor coincides with a specific edge of the calibration plate;

[0034] Step 104: Keep the posture of the robot unchanged, move the position of the robot, and obtain the third point position of the end of the robot tool when the center point TCP of the robot tool is aligned with the spatial identification point on the calibration plate;

[0035] Step 105: Constructing a mathematical model for hand-eye calibration of the robot and the laser sensor;

[0036] Step 106: Based on the first point, the second point, the third point and the hand-eye calibration mathematical model, determine the calibration matrix between the robot and the laser sensor.

[0037] In a specific embodiment, a user coordinate system of the robot is established by using a three-point method based on a calibration plate; the robot is moved according to the user coordinate system to obtain the first point position of the end of the robot tool when the laser near field of view of the laser sensor coincides with a specific edge of the calibration plate; the robot is moved according to the user coordinate system to obtain the second point position of the end of the robot tool when the laser far field of view of the laser sensor coincides with a specific edge of the calibration plate; the robot posture is kept unchanged, the position of the robot is moved, and the third point position of the end of the robot tool when the center point TCP of the robot tool is aligned with the spatial recognition point on the calibration plate is obtained; a hand-eye calibration mathematical model of the robot and the laser sensor is constructed; based on the first point position, the second point position, the third point position and the hand-eye calibration mathematical model, the calibration matrix between the robot and the laser sensor is determined. Only three points need to be determined and a hand-eye calibration mathematical model needs to be constructed to complete the calibration, which avoids the error caused by the manual teaching in the prior art that causes the laser to irradiate the recognition point multiple times, which not only simplifies the calibration method, but also improves the calibration accuracy.

[0038] In the embodiment of the present invention, Figure 2 As shown, the robot is placed on the ground or on other walking axes for fixed installation. The laser sensor is fixedly installed on the robot's sixth joint axis, or gripper, or welding gun and other preset positions, and the laser sensor is a straight-line laser sensor. After the robot, straight-line laser sensor and calibration plate are installed, a local area network consisting of the sensor, industrial computer and robot is constructed for communication. The straight-line laser sensor and industrial computer communicate through the protocol agreed upon by the sensor, and the industrial computer and robot communicate through the protocol agreed upon by the robot. The straight-line laser sensor and the robot do not communicate directly. The three together form a local area network, and the industrial computer is used to collect and obtain the position information of the two and perform algorithm processing. In the figure, the base coordinate system of the robot is X R , Y R , Z R The coordinate system shown, X L , Y L , Z L The coordinate system shown is the laser sensor coordinate system, X T , Y T , Z TThe coordinate system shown is the tool coordinate system of the robot.

[0039] Since the laser emitted by the straight-line laser sensor is linear and has a limited field of view, the workpiece cannot be identified if the distance between it and the workpiece is not within the field of view. Within the field of view, the first preset range that is closer to the workpiece is defined as the laser near field of view, and the first preset range that is farther from the workpiece is defined as the laser far field of view. For example, assuming the field of view of the laser is 300-500mm, the workpiece cannot be identified if the distance between the laser and the workpiece is less than 300mm or greater than 500mm. The near field of view can be defined as close to 300mm, and the far field of view can be defined as close to 500mm.

[0040] Before calibration, preparation operations are required, including: calibrating the robot's TCP (Tool Central Point). Since the technology for calibrating the robot's TCP is relatively mature, it will not be described in detail here. In the specific embodiments of the present invention, the calibration method provided by each brand of robot shall prevail. For example, a standard calibration ruler or calibration block may be used for calibration. If conditions are not met, a non-L1 method may be used for calibration, that is, the XYZ distances from the end of the tool to the center of the flange are measured in sequence. The angle parameters shall be based on those provided by the welding gun manufacturer and then filled in the robot tool parameters.

[0041] Based on the calibration plate, the robot's user coordinate system is established using the three-point method, and the calibration plate is placed within the robot's reachable range, which refers to the range that the robot's mechanical arm can reach through operations such as movement or rotation. The specific implementation process includes: adjusting the robot's gun posture so that the angle between the laser beam of the laser sensor and the plane of the calibration plate is within a preset range, generally vertical or approximately vertical, and the laser beam of the laser sensor coincides with or is parallel to a specific edge of the calibration plate.

[0042] The calibration plate is generally placed on a platform and within the reach of the robot so that the spatial identification points on the calibration plate can be identified. In a specific embodiment, the calibration plate is generally rectangular. In order to facilitate the accurate capture of the spatial identification points on the calibration plate, Figure 3 As shown, the calibration plate is formed by welding two plates together, one large and one small, and the spatial identification point is located at the overlap weld of the two plates.

[0043] The robot's user coordinate system is a rectangular coordinate system customized by the user for each workspace. It is used for teaching and executing position registers, executing position compensation instructions, etc. The method for establishing the user coordinate system is relatively simple. It is generally achieved by teaching three teaching points. The first teaching point is the origin of the user coordinate system. The second teaching point is on the X-axis. The line from the first teaching point to the second teaching point is the X-axis, and the direction indicated is the positive direction of X. The third teaching point is in the positive direction area of ​​the Y-axis, and the Z-axis is determined by the right-hand rule. The user coordinate system in the specific embodiment is as follows: Figure 4 As shown in the figure, P0 is the first point set and is also the origin of the user coordinate system. X The second point is set from P0 to P X , which is the X direction of the user coordinate system (X s direction shown), P Y The third point is used to calculate the Y direction of the user coordinate system (Y s The Z direction of the user coordinate system can be determined by the right-hand rule. For the convenience of later use, try to adjust the robot's welding gun posture so that the laser beam of the laser sensor is approximately perpendicular to the plane of the calibration plate and is aligned with the specific edge of the calibration plate (with the Y s The parallel sides, i.e. Figure 4 The sides where the middle edge 1 is located are parallel or coincident.

[0044] After establishing the robot's user coordinate system, move the robot according to the user coordinate system to obtain the first point position of the robot tool end when the laser near field of view of the laser sensor coincides with the specific edge of the calibration plate. The specific implementation process includes:

[0045] Keep the welding gun posture unchanged, and move the robot according to the user coordinate system so that the center of the laser near field of view of the laser sensor can identify the identification point of the calibration plate;

[0046] Move the user coordinate system's X s Direction makes the laser beam of the laser sensor coincide with the specific edge of the calibration plate, and the position of the end of the robot tool at this time is recorded as the first point P1.

[0047] Next, the robot is moved according to the user coordinate system to obtain the second point position of the robot tool end when the laser far field of view of the laser sensor coincides with the specific edge of the calibration plate. The specific implementation process includes:

[0048] Keep the welding gun posture unchanged, and move the robot according to the user coordinate system so that the center of the laser far field of view of the laser sensor can identify the identification point of the calibration plate;

[0049] Move the user coordinate system's X sDirection makes the laser beam of the laser sensor coincide with the specific edge of the calibration plate, and the position of the end of the robot tool at this time is recorded as the second point P2.

[0050] After obtaining P2, keep the robot's posture unchanged, move the robot's position, and obtain the third point of the robot tool end when the robot tool center point TCP is aligned with the spatial identification point on the calibration plate. The specific process includes: keep the above-mentioned welding gun posture unchanged, move the robot's position so that the robot TCP is aligned with the spatial identification point on the calibration plate, and record the position of the robot tool end at this time as the third point P3.

[0051] Next, a mathematical model for hand-eye calibration of the robot and laser sensor is constructed. The specific mathematical model is:

[0052]

[0053] Where P represents the position of the spatial recognition point in the robot base coordinates; P i Represents the coordinates of the space recognition point in the robot base coordinate system when the laser sensor illuminates it; represents the rotation matrix from the robot tool coordinate system to the base coordinate system, which can be obtained by the robot Euler angle transformation; P Laser Represents the position of the spatial identification point in the laser sensor coordinate system; Represents the transformation matrix relationship from the laser sensor coordinate system to the tool coordinate system, an unknown quantity; M TL Represents the translation component, an unknown quantity.

[0054] After rearranging the above formula, we can get

[0055] make

[0056] Then we have:

[0057]

[0058] For the above equation, each equation has 4 unknowns. By collecting 4 sets of coordinate data, three nonlinear equations can be obtained. Taking the first equation in the above equation as an example, we can get:

[0059]

[0060] In the formula, X bi , Y bi , Z bi Respectively represent the coordinate components of the spatial identification point in the i-th (i=1, 2, 3, 4) group of laser sensor coordinate systems in the X, Y, and Z directions; airepresents the P of the robot base coordinate system of the i-th group (i=1, 2, 3, 4) i The coordinates are calculated to get C a The component in the X direction.

[0061] Then the coefficients of the calibration matrix are:

[0062]

[0063] Similarly, by transforming and solving the second and third equations, we can finally determine and M TL .

[0064] Therefore, after the hand-eye calibration mathematical model of the robot and the laser sensor is constructed, the calibration matrix between the robot and the laser sensor is determined based on the first point, the second point, the third point and the hand-eye calibration mathematical model. In specific implementation, the offset distance parameter is set; the first point P1, the second point P2, and the four recognition points are transformed according to the offset distance parameter, and the four recognition points and the third point P3 are input into the hand-eye calibration mathematical model to calculate the calibration matrix between the robot and the laser sensor.

[0065] Specifically, the above calculation process is implemented by an industrial computer, and the offset distance parameters are set in the robot automatic calibration program. The automatic calibration process is a robot teaching program written. The instructions of each robot manufacturer are different, but basically contain instructions such as obtaining the current position of the robot and offsetting according to the specified parameters. The industrial computer first receives the offset distance parameters set by the user and runs the robot automatic calibration program. During the operation, P1 and P2 are transformed according to the offset distance parameters, and four recognition points on the left and right sides of the far field of view and the left and right sides of the near field of view can be obtained respectively. The industrial computer collects the robot posture corresponding to the four recognition points and P3 and the coordinates in the laser sensor coordinate system, and inputs them into the hand-eye calibration mathematical model. According to the solution and derivation process of the above hand-eye calibration mathematical model, the calibration matrix between the robot and the laser sensor can be calculated.

[0066] Among them, the offset distance parameters include: S X and S Y , S X The value is the distance from the spatial recognition point on the calibrated plate to the specific edge of the calibration plate, S Y The value of is related to the laser beam length of the laser sensor, and is generally half of the recognizable length of the laser beam in the near field of view.

[0067] like Figure 5 As shown in the figure, the processing flow of the robot automatic calibration program is as follows. After obtaining the three points P1, P2, and P3 in sequence, the left and right offsets S are set. X , and set the forward offset SY .

[0068] In the robot's user coordinate system, move point P1 along the X S Direction deviation S X , along Y S Direction deviation S Y Get the identification point S1; in the robot's user coordinate system, move point P1 along the X S Direction deviation S X , along Y S Direction offset - Y Get the identification point S2; in the robot's user coordinate system, move point P2 along the X S Direction deviation S X , along Y S Direction deviation S Y Get the identification point S3; in the robot's user coordinate system, move point P2 along the X S Direction deviation S X , along Y S Direction offset - Y The identification point S4 is obtained.

[0069] The industrial computer collects the poses in the robot coordinate system corresponding to the P3, S1, S2, S3, and S4 points, and the positions in the laser sensor coordinate system corresponding to the S1, S2, S3, and S4 points, and substitutes them into the constructed hand-eye calibration mathematical model to determine the calibration matrix between the robot and the laser sensor.

[0070] Based on the same inventive concept, the embodiment of the present invention also provides a robot and laser sensor hand-eye calibration device, the principles of solving the problems are similar, and the repeated parts are not repeated. The specific structure is as follows Figure 6 As shown, including:

[0071] The user coordinate system establishment module 601 is used to establish the user coordinate system of the robot based on the calibration plate using the three-point method; the calibration plate is placed within the reach of the robot;

[0072] A first point position acquisition module 602 is used to move the robot according to the user coordinate system to acquire the first point position of the robot tool end when the laser near field of view of the laser sensor coincides with a specific edge of the calibration plate;

[0073] The second point position acquisition module 603 is used to move the robot according to the user coordinate system to obtain the second point position of the robot tool end when the laser far field of view of the laser sensor coincides with a specific edge of the calibration plate;

[0074] The third point position acquisition module 604 is used to keep the posture of the robot unchanged, move the position of the robot, and obtain the third point position of the robot tool end when the robot tool center point TCP is aligned with the space identification point on the calibration plate;

[0075] Mathematical model building module 605, used to build a hand-eye calibration mathematical model for the robot and the laser sensor;

[0076] A calibration matrix determination module 606 is used to determine a calibration matrix between the robot and the laser sensor based on the first point, the second point, the third point and the hand-eye calibration mathematical model;

[0077] Wherein, the laser sensor is installed on the robot, and the laser sensor is set to be a straight line laser sensor.

[0078] The robot and laser sensor hand-eye calibration device in the specific embodiment, Figure 6 It also includes: TCP calibration module, which is used to perform TCP calibration of the robot.

[0079] During specific implementation, the user coordinate system establishment module 601 is specifically used to: adjust the robot's welding gun posture so that the angle between the laser beam of the laser sensor and the plane of the calibration plate is within a preset range, and the laser beam of the laser sensor coincides with or is parallel to a specific edge of the calibration plate.

[0080] In a specific embodiment, the first point acquisition module 602 is specifically used for:

[0081] Keep the welding gun posture unchanged, and move the robot according to the user coordinate system so that the center of the laser near field of view of the laser sensor can identify the identification point of the calibration plate;

[0082] Move the user coordinate system's X s Direction makes the laser beam of the laser sensor coincide with the specific edge of the calibration plate, and the position of the end of the robot tool at this time is recorded as the first point.

[0083] In a specific embodiment, the second point acquisition module 603 is specifically used to:

[0084] Keep the welding gun posture unchanged, and move the robot according to the user coordinate system so that the center of the laser far field of view of the laser sensor can identify the identification point of the calibration plate;

[0085] Move the user coordinate system's X s Direction makes the laser beam of the laser sensor coincide with the specific edge of the calibration plate, and the position of the end of the robot tool at this time is recorded as the second point.

[0086] In a specific embodiment, the third point acquisition module 604 is specifically used to:

[0087] Keep the welding gun posture unchanged, move the robot so that the robot TCP is aligned with the spatial identification point on the calibration plate, and record the position of the robot tool end at this time as the third point.

[0088] In a specific embodiment, the mathematical model building module 605 is specifically used to:

[0089] The mathematical model for hand-eye calibration of robots and laser sensors is:

[0090]

[0091] Where P represents the position of the spatial recognition point in the robot base coordinates; P i Represents the coordinates of the space recognition point in the robot base coordinate system when the laser sensor illuminates it; Represents the rotation matrix from the robot tool coordinate system to the base coordinate system; P Laser Represents the position of the spatial identification point in the laser sensor coordinate system; Represents the transformation matrix relationship from the laser sensor coordinate system to the tool coordinate system; M TL Represents the translation component.

[0092] In a specific embodiment, the calibration matrix determination module 606 is specifically used to:

[0093] Set the offset distance parameters;

[0094] The first point and the second point are transformed according to the offset distance parameter to obtain four recognition points. The four recognition points and the third point are input into the hand-eye calibration mathematical model to calculate the calibration matrix between the robot and the laser sensor.

[0095] In summary, the robot and laser sensor hand-eye calibration method and device provided in this specific embodiment have the following advantages:

[0096] By using the calibration plate and the three-point method to establish the user coordinate system of the robot; moving the robot according to the user coordinate system, obtaining the first point position of the robot tool end when the laser near field of view of the laser sensor coincides with the specific edge of the calibration plate; moving the robot according to the user coordinate system, obtaining the second point position of the robot tool end when the laser far field of view of the laser sensor coincides with the specific edge of the calibration plate; keeping the robot's posture unchanged, moving the robot's position, obtaining the third point position of the robot tool end when the robot tool center point TCP is aligned with the spatial recognition point on the calibration plate; constructing the hand-eye calibration mathematical model of the robot and the laser sensor; based on the first point position, the second point position, the third point position and the hand-eye calibration mathematical model, determining the calibration matrix between the robot and the laser sensor. Only three points need to be determined and the hand-eye calibration mathematical model needs to be constructed to complete the calibration, avoiding the error caused by the manual teaching in the prior art that causes the laser to irradiate the recognition point multiple times, which not only simplifies the calibration method, but also improves the calibration accuracy. And there is no need for multiple manual teaching, which is also convenient for on-site debugging and maintenance, reducing the time cost of debugging.

[0097] Although the present invention provides method operation steps as described in the embodiments or flowcharts, more or fewer operation steps may be included based on conventional or non-creative labor. The order of steps listed in the embodiments is only one way of executing the order of many steps and does not represent the only execution order. When the actual device or client product is executed, it can be executed in sequence or in parallel according to the method shown in the embodiments or the drawings (for example, in a parallel processor or multi-threaded processing environment).

[0098] It should be understood by those skilled in the art that the embodiments of this specification may be provided as methods, devices (systems) or computer program products. Therefore, the embodiments of this specification may take the form of complete hardware embodiments, complete software embodiments or embodiments combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0099] The present invention is described with reference to flowcharts and / or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as a combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0100] These computer program instructions may also be stored in a computer readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0101] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1The steps for the functions specified in one or more boxes.

[0102] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment. In this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0103] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other. The present invention is not limited to any single aspect, nor to any single embodiment, nor to any combination and / or replacement of these aspects and / or embodiments. Moreover, each aspect and / or embodiment of the present invention may be used alone or in combination with one or more other aspects and / or embodiments thereof.

[0104] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. These modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and specification of the present invention.

Claims

1. A robot and laser sensor hand-eye calibration method, characterized in that: The laser sensor is installed on the robot, and the hand-eye calibration method of the robot and the laser sensor includes: Based on the calibration plate, a user coordinate system of the robot is established by using a three-point method; the calibration plate is placed within the reach of the robot; Moving the robot according to the user coordinate system to obtain the first point position of the robot tool end when the laser near field of view of the laser sensor coincides with a specific edge of the calibration plate; Moving the robot according to the user coordinate system to obtain a second point position of the robot tool end when the laser far field of view of the laser sensor coincides with a specific edge of the calibration plate; Keeping the posture of the robot unchanged, moving the position of the robot, and obtaining the third point position of the end of the robot tool when the robot tool center point TCP is aligned with the spatial identification point on the calibration plate; Construct mathematical models for hand-eye calibration of robots and laser sensors; Determine a calibration matrix between the robot and the laser sensor based on the first point, the second point, the third point and the hand-eye calibration mathematical model; The mathematical model for constructing the hand-eye calibration of the robot and the laser sensor is: Where P represents the position of the spatial recognition point in the robot base coordinates; P i Represents the coordinates of the space recognition point in the robot base coordinate system when the laser sensor illuminates it; Represents the rotation matrix from the robot tool coordinate system to the base coordinate system; P Laser Represents the position of the spatial identification point in the laser sensor coordinate system; Represents the transformation matrix relationship from the laser sensor coordinate system to the tool coordinate system; M TL Represents the translation component.

2. The robot and laser sensor hand-eye calibration method according to claim 1, characterized in that: The laser sensor is a line laser sensor.

3. The robot and laser sensor hand-eye calibration method according to claim 1, characterized in that: Also includes: Perform TCP calibration of the robot.

4. The robot and laser sensor hand-eye calibration method according to claim 1, characterized in that: Based on the calibration plate, the user coordinate system of the robot is established using the three-point method, including: The welding gun posture of the robot is adjusted so that the angle between the laser beam of the laser sensor and the plane of the calibration plate is within a preset range, and the laser beam of the laser sensor coincides with or is parallel to a specific edge of the calibration plate.

5. The robot and laser sensor hand-eye calibration method according to claim 4, characterized in that: Moving the robot according to the user coordinate system to obtain the first point position of the robot tool end when the laser near field of view of the laser sensor coincides with a specific edge of the calibration plate, including: Keeping the welding gun posture unchanged, the robot is moved according to the user coordinate system so that the center of the laser near field of view of the laser sensor can identify the identification point of the calibration plate; Move the X coordinate system of the user s The direction is such that the laser beam of the laser sensor coincides with a specific edge of the calibration plate, and the position of the end of the robot tool at this time is recorded as the first point position.

6. The robot and laser sensor hand-eye calibration method according to claim 4, characterized in that: Moving the robot according to the user coordinate system to obtain a second point position of the robot tool end when the laser far field of view of the laser sensor coincides with a specific edge of the calibration plate, including: Keeping the welding gun posture unchanged, the robot is moved according to the user coordinate system so that the center of the laser far field of view of the laser sensor can identify the identification point of the calibration plate; Move the X coordinate system of the user s The direction is such that the laser beam of the laser sensor coincides with a specific edge of the calibration plate, and the position of the end of the robot tool at this time is recorded as the second point position.

7. The robot and laser sensor hand-eye calibration method according to claim 4, characterized in that: Keeping the posture of the robot unchanged, moving the position of the robot, and obtaining the third point position of the end of the robot tool when the robot tool center point TCP is aligned with the spatial identification point on the calibration plate, including: Keeping the welding gun posture unchanged, move the position of the robot so that the robot TCP is aligned with the spatial identification point on the calibration plate, and record the position of the robot tool end at this time as the third point position.

8. The robot and laser sensor hand-eye calibration method according to claim 1, characterized in that: Based on the first point, the second point, the third point and the hand-eye calibration mathematical model, a calibration matrix between the robot and the laser sensor is determined, including: Set the offset distance parameters; The first point and the second point are transformed according to the offset distance parameter to obtain four identification points, and the four identification points and the third point are input into the hand-eye calibration mathematical model to calculate the calibration matrix between the robot and the laser sensor.

9. A robot and laser sensor hand-eye calibration device, characterized in that: include: A user coordinate system establishment module, used to establish the user coordinate system of the robot using a three-point method based on a calibration plate; The calibration plate is placed within the reachable range of the robot; A first point position acquisition module is used to move the robot according to the user coordinate system to obtain a first point position of the robot tool end when the laser near field of view of the laser sensor coincides with a specific edge of the calibration plate; A second point position acquisition module is used to move the robot according to the user coordinate system to obtain a second point position of the robot tool end when the laser far field of view of the laser sensor coincides with a specific edge of the calibration plate; A third point position acquisition module is used to keep the posture of the robot unchanged, move the position of the robot, and acquire the third point position of the end of the robot tool when the robot tool center point TCP is aligned with the spatial identification point on the calibration plate; Mathematical model building module, used to build the hand-eye calibration mathematical model of the robot and laser sensor; A calibration matrix determination module, used to determine a calibration matrix between the robot and the laser sensor based on the first point, the second point, the third point and the hand-eye calibration mathematical model; Wherein, the laser sensor is installed on the robot; The mathematical model building module is used to build the hand-eye calibration mathematical model of the robot and the laser sensor: Where P represents the position of the spatial recognition point in the robot base coordinates; P i Represents the coordinates of the space recognition point in the robot base coordinate system when the laser sensor illuminates it; Represents the rotation matrix from the robot tool coordinate system to the base coordinate system; P Laser Represents the position of the spatial identification point in the laser sensor coordinate system; Represents the transformation matrix relationship from the laser sensor coordinate system to the tool coordinate system; M TL Represents the translation component.

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