Parameter deviation determination method, apparatus and tool, storage medium, and computer device

Abstract

The present invention provides a parameter deviation determination method, apparatus and tool, a storage medium, and a computer device. The method comprises: determining that an adapter board is fixed to the tail end of a robot, wherein a calibration probe and a camera are fixed on the adapter board, and the robot is fixed on a base; controlling the robot to move, such that the calibration probe comes into contact with a calibration board, and obtaining a first relative position relationship between the calibration board and the base; controlling the tail end to move toward a calibration point, and when the tail end moves to the calibration point, controlling the camera to capture an image, wherein the image comprises the calibration board; on the basis of the image and the first relative position relationship, determining a second relative position relationship between the camera and the base during image capturing; and on the basis of the second relative position relationship and an ideal kinematics parameter of the robot, determining a kinematics parameter deviation of the robot. The present invention solves the technical problems that the robot kinematics parameter calibration process has high costs and low efficiency, and a calibration device is not portable.

Description

Parameter deviation determination method, device, tooling, storage medium and computer equipment

[0001] This disclosure claims priority to Chinese patent application number 2024100775206, filed with the Patent Office of China on January 18, 2024, entitled “Parameter Deviation Determination Method, Device, Tooling, Storage Medium and Computer Equipment,” the entire contents of which are incorporated by reference into this disclosure. Technical Field

[0002] The present disclosure relates to the field of program control, and in particular to a method, apparatus, tooling, storage medium, and computer equipment for determining parameter deviation. Background Art

[0003] Industrial robots play an irreplaceable role in the manufacturing industry, demonstrating their remarkable expertise in improving production efficiency, ensuring product quality, and reducing production costs. Industrial robots possess a high degree of precision and stability, enabling them to efficiently perform repetitive and tedious tasks, significantly improving overall production line efficiency. Robotic accuracy is primarily measured in two key areas: absolute accuracy and repeatability. These two key performance indicators are crucial. Absolute accuracy describes the accuracy of a robot's actual position relative to the global coordinate system when performing a task; repeatability assesses the consistency with which the end effector or tool returns to the same relative position when performing the same task multiple times. Robots generally achieve good repeatability but struggle to achieve absolute accuracy. However, in precision manufacturing fields such as aerospace, automotive, and electronics, robots require high absolute accuracy to complete their tasks.

[0004] The absolute accuracy of a robot is primarily affected by the deviation of its kinematic parameters, of which approximately 80% can be attributed to the inaccuracy of the kinematic parameters. Therefore, the identification of the robot's kinematic parameters is crucial. Robot manufacturers typically perform kinematic parameter identification on the robot before it ships, but if the robot is damaged at the job site, it will require repair. After on-site repairs, the robot's kinematic parameters often change, resulting in inaccurate kinematic parameters for the repaired robot, leading to poor absolute accuracy and the inability to complete the desired task. Common calibration equipment, such as laser trackers and coordinate measuring machines, offer high-precision calibration performance, but their high cost and bulk limit their flexible application on-site. Therefore, the development of a portable, efficient, cost-effective, and practical on-site calibration device is crucial.

[0005] To address the above-mentioned problems, no effective solutions have been proposed so far.

[0006] Summary of the Invention

[0007] The embodiments of the present disclosure provide a parameter deviation determination method, apparatus, tooling, storage medium, and computer equipment to at least solve the technical problems of high cost and low efficiency in the robot kinematic parameter calibration process and the non-portability of the calibration equipment.

[0008] According to one aspect of an embodiment of the present disclosure, a parameter deviation determination method is provided, including: determining that an adapter plate is fixed to an end of a robot, wherein a calibration pin and a camera are fixed on the adapter plate, and the robot is fixed on a base; controlling the robot to move so that the calibration pin contacts the calibration plate to obtain a first relative position relationship between the calibration plate and the base; controlling the end to move toward a calibration point, and when the end moves to the calibration point, controlling the camera to take a photo, wherein the photo includes the calibration plate; determining a second relative position relationship between the camera and the base when taking the photo based on the photo and the first relative position relationship; determining the kinematic parameter deviation of the robot based on the second relative position relationship and the ideal kinematic parameters of the robot.

[0009] In some embodiments, determining the kinematic parameter deviation of the robot based on the second relative position relationship and the ideal kinematic parameters of the robot includes: obtaining the camera physical parameters of the camera and the adapter plate physical parameters of the adapter plate; obtaining the first motion control parameters of the robot when the end moves to the calibration point; determining the third relative position relationship between the end and the base when taking the photo based on the first motion control parameters and the ideal kinematic parameters; determining the kinematic parameter deviation based on the second relative position relationship, the third relative position relationship, the camera physical parameters and the adapter plate physical parameters.

[0010] In some embodiments, determining the kinematic parameter deviation based on the second relative position relationship, the third relative position relationship, the camera physical parameters and the adapter plate physical parameters includes: constructing a positive kinematic model of the robot; determining the first position deviation of the camera in the calibration plate coordinate system based on the first relative position relationship, the second relative position relationship, the third relative position relationship, the adapter plate physical parameters and the camera physical parameters; determining the first constraint equation between the first position deviation and the parameter deviation to be identified based on the positive kinematic model, the adapter plate physical parameters and the camera physical parameters, wherein the parameter deviation to be identified includes: the kinematic parameter deviation, the deviation of the first relative position relationship, and the deviation of the position relationship between the camera and the end; solving the first constraint equation based on the first position deviation to obtain the parameter deviation to be identified.

[0011] In some embodiments, determining the first position deviation of the camera in the calibration plate coordinate system based on the first relative position relationship, the second relative position relationship, the third relative position relationship, the physical parameters of the adapter plate, and the physical parameters of the camera includes: determining the fourth relative position relationship between the end and the calibration plate when taking the photo based on the first relative position relationship and the third relative position relationship; determining the fifth relative position relationship between the camera and the calibration plate when taking the photo based on the fourth relative position relationship, the physical parameters of the adapter plate, and the physical parameters of the camera; determining the sixth relative position relationship between the camera and the calibration plate when taking the photo based on the photo; and determining the first position deviation based on the deviation between the fifth relative position relationship and the sixth relative position relationship.

[0012] In some embodiments, solving the first constraint equation based on the first position deviation to obtain the parameter deviation to be identified includes: substituting the first position deviation into the first constraint equation to obtain the equation to be solved; and solving the equation to be solved using the overall least squares method to obtain the parameter deviation to be identified.

[0013] In some embodiments, determining the kinematic parameter deviation based on the second relative position relationship, the third relative position relationship, the camera physical parameters and the adapter plate physical parameters includes: constructing a positive kinematic model of the robot; determining the seventh relative position relationship between the end and the base when taking the photo based on the second relative position relationship, the camera physical parameters and the adapter plate physical parameters; determining the second position deviation of the end based on the deviation between the third relative position relationship and the seventh relative position relationship; determining the second constraint equation between the second position deviation and the kinematic parameter deviation based on the positive kinematic model; solving the second constraint equation based on the second position deviation to obtain the kinematic parameter deviation.

[0014] In some embodiments, controlling the movement of the robot so that the calibration needle contacts the calibration plate to obtain a first relative position relationship between the calibration plate and the base includes: acquiring the adapter plate physical parameters of the adapter plate and the calibration needle physical parameters of the calibration needle; controlling the movement of the robot so that the calibration needle contacts the calibration plate, and recording second motion control parameters of the robot; and determining the first relative position relationship based on the second motion control parameters, the calibration needle physical parameters, and the adapter plate physical parameters.

[0015] In some embodiments, controlling the movement of the robot so that the calibration needle contacts the calibration plate and recording the second motion control parameters of the robot includes: selecting multiple position points on the calibration plate; controlling the movement of the robot so that the calibration needle contacts the multiple position points respectively, and recording the second motion control parameters corresponding to each of the calibration needles when they contact the multiple position points respectively; determining the first relative position relationship based on the second motion control parameters, the physical parameters of the calibration needle and the physical parameters of the adapter plate includes: determining the eighth relative position relationship between the end and the base when the calibration needle contacts the multiple position points respectively according to the second motion control parameters; determining the ninth relative position relationship between the calibration needle and the base when the calibration needle contacts the multiple position points respectively according to the eighth relative position relationship, the physical parameters of the calibration needle and the physical parameters of the adapter plate; and determining the first relative position relationship based on the ninth relative position relationship.

[0016] According to another aspect of an embodiment of the present disclosure, a parameter deviation determination device is also provided, including: a first determination component, configured to determine that an adapter plate is fixed to the end of a robot, wherein a calibration pin and a camera are fixed on the adapter plate, and the robot is fixed on a base; a first control component, configured to control the movement of the robot so that the calibration pin contacts the calibration plate to obtain a first relative position relationship between the calibration plate and the base; a second control component, configured to control the end to move toward a calibration point, and when the end moves to the calibration point, control the camera to take a photo, wherein the photo includes the calibration plate; a second determination component, configured to determine a second relative position relationship between the camera and the base when taking the photo based on the photo and the first relative position relationship; a third determination component, configured to determine the kinematic parameter deviation of the robot based on the second relative position relationship and the ideal kinematic parameters of the robot.

[0017] According to another aspect of an embodiment of the present disclosure, a parameter deviation determination tool is also provided, including: a camera, an adapter plate, a calibration pin and a calibration plate; wherein, the camera and the calibration pin are fixed on the adapter plate, the adapter plate is fixed on the end of the robot, and the calibration plate is set in the following position: the movement of the robot is controlled so that the calibration pin can contact the calibration plate.

[0018] According to another aspect of the embodiments of the present disclosure, a non-volatile storage medium is further provided, wherein the non-volatile storage medium includes a stored program, wherein when the program is running, the device where the non-volatile storage medium is located is controlled to execute any one of the above-mentioned parameter deviation determination methods.

[0019] According to another aspect of an embodiment of the present disclosure, a computer device is further provided, comprising a memory and a processor, wherein the memory is used to store programs, and the processor is used to run the programs stored in the memory, wherein when the program is run, any one of the above-mentioned parameter deviation determination methods is executed.

[0020] In the embodiment of the present disclosure, an adapter plate is fixed to the end of the robot, wherein the calibration pin and the camera are fixed to the adapter plate, and the robot is fixed to the base; the robot is controlled to move so that the calibration pin contacts the calibration plate, and a first relative position relationship between the calibration plate and the base is obtained; the end is controlled to move toward the calibration point, and when the end moves to the calibration point, the camera is controlled to take a photo, wherein the photo includes the calibration plate; based on the photo and the first relative position relationship, the second relative position relationship between the camera and the base when taking the photo is determined; based on the second relative position relationship and the ideal kinematic parameters of the robot, the kinematic parameter deviation of the robot is determined, thereby achieving the purpose of accurately determining the kinematic parameter deviation of the robot, thereby realizing the technical effect of efficiently and low-costly measuring the kinematic parameter deviation of the robot, and further solving the technical problems of high cost and low efficiency of the robot kinematic parameter calibration process and non-portability of the calibration equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The drawings described herein are used to provide a further understanding of the present disclosure and constitute a part of the present disclosure. The exemplary embodiments of the present disclosure and their descriptions are used to explain the present disclosure and do not constitute an improper limitation of the present disclosure. In the drawings:

[0022] FIG1 shows a hardware structure block diagram of a computer terminal for implementing a parameter deviation determination method;

[0023] FIG2 is a flow chart of a method for determining parameter deviation according to an embodiment of the present disclosure;

[0024] FIG3 is a schematic diagram of a parameter deviation determination tool provided according to some embodiments of the present disclosure;

[0025] FIG4 is a schematic diagram of a coordinate system in a tool for determining parameter deviation according to some embodiments of the present disclosure;

[0026] FIG5 is a schematic diagram of a robot kinematic parameter identification process according to some embodiments of the present disclosure;

[0027] FIG6 is a schematic diagram of a flow chart of an overall least squares solution according to some embodiments of the present disclosure;

[0028] FIG7 is a schematic diagram of kinematic parameter accuracy verification results of the robot 1 according to some embodiments of the present disclosure;

[0029] FIG8 is a schematic diagram of kinematic parameter accuracy verification results of the robot 2 according to some embodiments of the present disclosure;

[0030] FIG9 is a structural block diagram of a device for determining parameter deviation according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0031] In order to enable those skilled in the art to better understand the solutions of the present disclosure, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the embodiments described are only part of the embodiments of the present disclosure, not all of the embodiments. Based on the embodiments of the present disclosure, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present disclosure.

[0032] It should be noted that the terms "first", "second", etc. in the specification and claims of the present disclosure and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present disclosure described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0033] According to an embodiment of the present disclosure, an embodiment of a method for determining parameter deviation is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0034] The method embodiments provided in the embodiments of the present disclosure can be executed in a mobile terminal, a computer terminal or a similar computing device. Figure 1 shows a hardware structure block diagram of a computer terminal for implementing a parameter deviation determination method. As shown in Figure 1, the computer terminal 10 may include one or more (processors 102a, 102b, ..., 102n are used in the figure to illustrate) processors (the processor may include but is not limited to a processing device such as a microprocessor MCU or a programmable logic device FPGA), a memory 104 for storing data. In addition, it may also include: a display, an input / output interface (I / O interface), a universal serial bus (USB) port (which may be included as one of the ports of the BUS bus), a network interface, a power supply and / or a camera. It will be understood by those skilled in the art that the structure shown in Figure 1 is only illustrative and does not limit the structure of the above-mentioned electronic device. For example, the computer terminal 10 may also include more or fewer components than those shown in Figure 1, or have a configuration different from that shown in Figure 1.

[0035] It should be noted that the one or more processors and / or other data processing circuits described above may generally be referred to herein as "data processing circuitry." The data processing circuitry may be embodied in whole or in part as software, hardware, firmware, or any other combination thereof. Furthermore, the data processing circuitry may be a single, independent processing component, or may be incorporated in whole or in part into any of the other components of the computer terminal 10. As described in the embodiments of the present disclosure, the data processing circuitry serves as a processor control (e.g., selection of a variable resistor terminal path connected to an interface).

[0036] The memory 104 can be used to store software programs and components of application software, such as the program instructions / data storage device corresponding to the parameter deviation determination method in the embodiment of the present disclosure. The processor executes various functional applications and data processing by running the software programs and components stored in the memory 104, that is, implementing the parameter deviation determination method of the above-mentioned application. The memory 104 may include a high-speed random access memory, and may also include a non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some instances, the memory 104 may further include a memory remotely arranged relative to the processor, and these remote memories can be connected to the computer terminal 10 via a network. Examples of the above-mentioned network include but are not limited to the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0037] The display may be, for example, a touch screen liquid crystal display (LCD) that enables a user to interact with a user interface of the computer terminal 10 .

[0038] To address the high labor, financial, and time costs associated with calibrating a robot's kinematic parameters, this disclosure proposes a low-cost, high-efficiency camera-based method and device for identifying robot kinematic parameters. Figure 2 is a flow chart of a parameter deviation determination method according to an embodiment of this disclosure. As shown in Figure 2, the method includes the following steps:

[0039] Step S201 , determining that an adapter plate is fixed to the end of the robot, wherein the calibration pin and the camera are fixed to the adapter plate, and the robot is fixed to the base.

[0040] Among them, the adapter plate is a rigid connection component used to connect the calibration pin and camera to the end of the robot, so that the calibration pin and camera move with the movement of the end of the robot. The robot is fixed on the base, and the coordinate position of the end of the robot can be called the tool center point (TCP). In order to complete various work tasks, various tools such as spray guns, grippers, welding guns, etc. can be installed on the end of the industrial robot. Since the shapes and sizes of tools are different, after replacing or adjusting the tools, the actual working point of the robot will change relative to the position of the end of the robot. The currently commonly used method is to establish a tool coordinate system on the robot tool, whose origin is the tool center point. The robot is programmed in this coordinate system. When the tool is adjusted, it is only necessary to recalibrate the position of the working coordinate system to put the robot back into use.

[0041] The calibration pin can be divided into a pointed end and a non-pointed end. The non-pointed end is rigidly fixed to the adapter plate, and the pointed end is used to indicate the position. The camera can be a 2D vision camera for taking pictures.

[0042] Step S202 : Control the robot to move so that the calibration needle contacts the calibration plate, and obtain a first relative position relationship between the calibration plate and the base.

[0043] In this step, the robot is controlled to move, specifically, the robot's joints are controlled to move while the robot is fixed to the base, so that the robot's end position changes. The calibration needle contacts the calibration plate, for example, the tip of the calibration needle touches the calibration plate.

[0044] A calibration target is a flat plate with an array of patterns at fixed intervals. These typically include solid circle arrays and chessboard patterns, such as the TI-TIMES CG-100-D with an evenly spaced solid circle array and the TI-TIMES CG-076-T with a chessboard pattern. Calibration targets can be used to correct lens distortion in applications such as machine vision, image measurement, photogrammetry, and 3D reconstruction. They can also be used to determine the conversion relationship between physical dimensions and pixels, and to determine the relationship between the 3D geometric position of a point on a spatial object's surface and its corresponding point in the image, thereby establishing a geometric model for camera imaging.

[0045] Since the physical parameters of the calibration needle, adapter plate, and robot are all known and will not change, the first relative position relationship between the calibration plate and the base can be quantitatively measured by controlling the robot movement to make the calibration needle contact the calibration plate. The first relative position relationship can be expressed using the calibration plate coordinate system {W b} is expressed in the base coordinate system {B}.

[0046] In some embodiments of the present disclosure, controlling the movement of the robot so that the calibration needle contacts the calibration plate to obtain a first relative position relationship between the calibration plate and the base includes the following steps: obtaining the adapter plate physical parameters of the adapter plate and the calibration needle physical parameters of the calibration needle; controlling the movement of the robot so that the calibration needle contacts the calibration plate to record the second motion control parameters of the robot; and determining the first relative position relationship based on the second motion control parameters, the calibration needle physical parameters, and the adapter plate physical parameters.

[0047] The physical parameters of the adapter plate and the calibration pin can be used to describe the physical dimensions of the adapter plate and calibration pin, respectively. Therefore, based on these physical parameters, the coordinates of the adapter plate and calibration pin in the robot's end-of-line coordinate system {TCP} can be determined. The end-of-line coordinate system {TCP} is a coordinate system established with the center of the robot's end-of-line flange as its origin. The coordinates of the calibration pin in {TCP} represent the relative positional relationship between the calibration pin and the robot's end-of-line.

[0048] The robot's second motion control parameters can be used to characterize how the robot moves its end-point to a position where the calibration needle contacts the calibration plate. For example, the second motion control parameters may include data such as the robot's joint angles and rotation angles. Based on the second motion control parameters, the coordinates of the robot's end-point in the base coordinate system of the robot's base can be calculated, thereby obtaining the relative positional relationship between the end-point and the base. Furthermore, once the relative positional relationship between the end-point and the base, the relative positional relationship between the calibration needle and the end-point have been obtained, and the calibration needle has contacted the calibration plate, a coordinate system transformation can be performed to obtain a description of the calibration plate in the base coordinate system, thereby obtaining the aforementioned first relative positional relationship.

[0049] In some embodiments of the present disclosure, the movement of the robot is controlled so that the calibration needle contacts the calibration plate, and the second motion control parameter of the robot is recorded, including: selecting multiple position points on the calibration plate; controlling the movement of the robot so that the calibration needle contacts the multiple position points respectively, and recording the second motion control parameters corresponding to each of the multiple position points when the calibration needle contacts the multiple position points respectively; determining the first relative position relationship according to the second motion control parameters, the physical parameters of the calibration needle, and the physical parameters of the adapter plate, including: determining the eighth relative position relationship between the end of the calibration needle and the base when the calibration needle contacts the multiple position points respectively according to the second motion control parameters; determining the ninth relative position relationship between the calibration needle and the base when the calibration needle contacts the multiple position points respectively according to the eighth relative position relationship, the physical parameters of the calibration needle, and the physical parameters of the adapter plate; and determining the first relative position relationship according to the ninth relative position relationship.

[0050] This optional embodiment provides a way to determine the first relative position relationship. In some embodiments of the present disclosure, a three-point teaching method can be used. The number of multiple position points can be three, namely the origin of the calibration plate coordinate system, a point on a coordinate axis of the calibration plate coordinate system, and a point in the quadrant of the coordinate system. The second motion control parameters of the robots are recorded when the calibration needle contacts these three points respectively. The posture of the robot when contacting these three points can be calculated, and the posture can represent the eighth relative position relationship between the end and the base. At this time, the coordinate system is converted in combination with the physical parameters of the adapter plate and the calibration needle. The representation of the tip of the calibration needle in the base coordinate system when the calibration needle contacts multiple position points can be determined, that is, the ninth relative position relationship, which is equivalent to the multiple position points on the calibration plate being represented in the base coordinate system. Therefore, the position of the calibration plate in the base coordinate system can be determined based on this, that is, the first relative position relationship is obtained.

[0051] Step S203 controls the end device to move toward a calibration point. When the end device reaches the calibration point, the camera is controlled to capture a photo, wherein the photo includes the calibration plate. The calibration point can be a position in space, and the end device's movement toward the calibration point can be understood as changing the end device's position in space. The location of the calibration point is not particularly required, as long as the calibration plate is captured when the camera captures the photo when the end device moves to the calibration point.

[0052] Step S204: Determine a second relative position relationship between the camera and the base when the photo is taken based on the photo and the first relative position relationship.

[0053] Because the photo includes the calibration plate, its spatial position relative to the camera can be determined by its appearance in the photo. For example, the calibration plate's position can be expressed in the camera coordinate system {C}. Furthermore, because the first relative position relationship defines the relative position between the calibration plate and the base, the camera's pose can be expressed in the base coordinate system {B} through coordinate system transformation, thus obtaining the second relative position relationship.

[0054] Step S205 : determining the kinematic parameter deviation of the robot according to the second relative position relationship and the ideal kinematic parameters of the robot.

[0055] Among them, the ideal kinematic parameters of the robot are the default kinematic parameters of the robot. This value may be determined based on the product specifications before the robot leaves the factory. However, due to the tolerance of the robot's mechanical structure, the robot may also have slight deviations from the default working state due to installation or usage conditions during on-site use, which may cause the actual kinematic parameters of the robot to be different from the ideal kinematic parameters. Therefore, the present disclosure identifies the kinematic parameter deviation of the robot through the above method, which is the deviation between the actual kinematic parameters of the robot and the ideal kinematic parameters. Based on this deviation, the kinematic parameters of the robot can be revised to make the subsequent operation of the robot more accurate. In this step, the second relative position relationship can represent the relative position relationship between the camera and the base at the calibration point. This position can be called the actual position of the camera; and the process of moving the camera to the calibration point can be calculated by the ideal kinematic parameters. Therefore, based on the ideal kinematic parameters, the theoretical position of the camera relative to the base at the calibration point can be calculated. Therefore, based on the difference between the actual position and the theoretical position, the kinematic parameter deviation of the robot can be estimated.

[0056] In some embodiments of the present disclosure, the kinematic parameter deviation of the robot is determined based on the second relative position relationship and the ideal kinematic parameters of the robot, which can be done in the following way: obtaining the camera physical parameters of the camera and the adapter plate physical parameters of the adapter plate; obtaining the first motion control parameters of the robot when the end moves to the calibration point; determining the third relative position relationship between the end and the base when taking a photo based on the first motion control parameters and the ideal kinematic parameters; determining the kinematic parameter deviation based on the second relative position relationship, the third relative position relationship, the camera physical parameters and the adapter plate physical parameters.

[0057] In this optional embodiment, based on the first motion control parameters and the ideal kinematic parameters, a third relative position relationship between the end terminal and the base can be calculated. This third relative position relationship can be considered as the theoretical position of the end terminal in the base coordinate system. This is because the theoretical position is not obtained by actual measurement, but is calculated based on the ideal kinematic parameters. It can be understood that the second relative position relationship is the position of the camera in the base coordinate system obtained by coordinate system conversion based on the image of the calibration plate taken by the photo. Therefore, the second relative position relationship can be considered as the actual position of the camera in the base coordinate system. The determination of the second relative position relationship includes a certain amount of actual measurement. Furthermore, the physical parameters of the camera and the physical parameters of the adapter plate can be used to determine the relative position relationship between the camera and the end terminal. Therefore, based on the second relative position relationship and combined with the physical parameters of the camera and the adapter plate, the coordinates of the end terminal in the base coordinate system, that is, the actual position of the end terminal in the base coordinate system, can be calculated.

[0058] In some embodiments of the present disclosure, the kinematic parameter deviation is determined based on the second relative position relationship, the third relative position relationship, the physical parameters of the camera and the physical parameters of the adapter plate, including: constructing a positive kinematic model of the robot; determining the first position deviation of the camera in the calibration plate coordinate system based on the first relative position relationship, the second relative position relationship, the third relative position relationship, the physical parameters of the adapter plate and the physical parameters of the camera; determining the first constraint equation between the first position deviation and the parameter deviation to be identified based on the positive kinematic model, the physical parameters of the adapter plate and the physical parameters of the camera, wherein the parameter deviation to be identified includes: the kinematic parameter deviation, the deviation of the first relative position relationship, and the deviation of the position relationship between the camera and the end; solving the first constraint equation based on the first position deviation to obtain the parameter deviation to be identified; and determining the kinematic parameter deviation based on the parameter deviation to be identified.

[0059] This optional embodiment provides a method for solving kinematic parameter deviations, wherein the forward kinematic model of the robot is a relational model that describes the relationship between the position and posture of the robot's end effector and the robot's joint angles, that is, given the robot's joint angles, the position and posture of the robot's end effector can be calculated.

[0060] The first position deviation of the camera in the calibration plate coordinate system is the deviation between the actual position and the theoretical position of the camera in the calibration plate coordinate system. The actual position can be calculated through photos, and the theoretical position can be calculated based on ideal kinematic parameters. Therefore, the deviation between the actual position and the theoretical position can reflect the deviation between the ideal kinematic parameters and the actual kinematic parameters of the robot. The actual kinematic parameters of the robot can be inferred based on the deviation, thereby completing the calibration of the actual kinematic parameters of the robot.

[0061] The first constraint equation constructed in this optional embodiment can list the kinematic parameter deviation, the deviation of the first relative position relationship and the deviation of the position relationship between the camera and the end as quantities to be solved. By comprehensively solving the above three types of deviations, the solution to the kinematic parameter deviation is made more accurate.

[0062] Among them, the first relative position relationship is the relative position relationship between the calibration plate and the base determined based on the calibration work of the calibration needle. Since ideal kinematic parameters need to be used for calculation when determining the first relative position relationship, and the ideal kinematic parameters are not accurate, the first relative position relationship is not absolutely accurate. There is a certain deviation between the first relative position relationship and the actual relative position relationship between the calibration plate and the base. This deviation is recorded as the first relative position relationship deviation.

[0063] The positional relationship between the camera and the end is the relative positional relationship between the camera and the end of the robot. The positional relationship between the camera and the end can be determined by coordinate system substitution based on the physical parameters of the camera and the physical parameters of the adapter plate. The physical parameters of the camera and the physical parameters of the adapter plate describe the external dimensions of the camera and the adapter plate under ideal conditions. Since there are certain tolerances in the production process of the camera and the adapter plate, there are deviations between the external dimension parameters of the camera and the adapter plate in actual use and the physical parameters of the camera and the physical parameters of the adapter plate. Therefore, there is a certain deviation between the positional relationship between the camera and the end obtained based on the calculation and the positional relationship between the camera and the end in the real scene. This deviation is the deviation of the positional relationship between the camera and the end.

[0064] In some embodiments of the present disclosure, a first position deviation of the camera in the calibration plate coordinate system is determined based on the first relative position relationship, the second relative position relationship, the third relative position relationship, the physical parameters of the adapter plate, and the physical parameters of the camera, including: determining a fourth relative position relationship between the end and the calibration plate when taking a photo based on the first relative position relationship and the third relative position relationship; determining a fifth relative position relationship between the camera and the calibration plate when taking a photo based on the fourth relative position relationship, the physical parameters of the adapter plate, and the physical parameters of the camera; determining a sixth relative position relationship between the camera and the calibration plate when taking the photo based on the photo; and determining the first position deviation based on the deviation between the fifth relative position relationship and the sixth relative position relationship.

[0065] Since the first relative position relationship represents the spatial position relationship between the calibration plate and the base, and the third relative position relationship represents the spatial position relationship between the terminal and the base when the photo is taken, the spatial position relationship between the terminal and the calibration plate when the photo is taken can be determined using the base coordinate system as the intermediate coordinate system for coordinate system transformation, i.e., the fourth relative position relationship. At this point, the spatial position relationship between the camera and the terminal can be determined using the physical parameters of the adapter plate and the camera. Therefore, based on the fourth relative position relationship, the fifth relative position relationship can be obtained. This fifth relative position relationship is the theoretical position of the camera in the calibration plate coordinate system when the photo is taken.

[0066] Since the actual image of the calibration plate taken in the photo is used, the sixth relative position relationship between the calibration plate and the camera can be directly calculated from the calibration plate image in the photo based on the imaging physics principle of the camera lens. The sixth relative position relationship can be considered to be the actual position of the camera in the calibration plate coordinate system when the photo is taken. Therefore, based on the deviation between the fifth relative position and the sixth relative position, the above-mentioned first deviation can be determined. The first position deviation of the camera in the calibration plate coordinate system is the deviation between the actual position and theoretical position of the camera in the calibration plate coordinate system.

[0067] In some embodiments of the present disclosure, solving the first constraint equation based on the first position deviation to obtain the parameter deviation to be identified includes: substituting the first position deviation into the first constraint equation to obtain the equation to be solved; and using the overall least squares method to solve the equation to be solved to obtain the parameter deviation to be identified.

[0068] The overall least squares method is a least squares method that simultaneously considers the errors and disturbances of the coefficient matrix A and the vector b to find the least squares solution for Ax = b. This method takes into account possible interference factors in the regression matrix. Since the parameters to be identified include three types of deviations, only the kinematic parameter deviations are the deviations actually required for the present disclosure, the overall least squares method can treat the other two types of deviations as errors and disturbances, ultimately improving the accuracy of the kinematic parameter deviation solution.

[0069] In some embodiments of the present disclosure, the kinematic parameter deviation is determined based on the second relative position relationship, the third relative position relationship, the camera physical parameters and the adapter plate physical parameters, including: constructing a positive kinematic model of the robot; determining the seventh relative position relationship between the end and the base when taking a photo based on the second relative position relationship, the camera physical parameters and the adapter plate physical parameters; determining the second position deviation of the end based on the deviation between the third relative position relationship and the seventh relative position relationship; determining the second constraint equation between the second position deviation and the kinematic parameter deviation based on the positive kinematic model; solving the second constraint equation based on the second position deviation to obtain the kinematic parameter deviation.

[0070] This optional embodiment also provides a method for solving the kinematic parameter deviation. The solution process proposed in this optional embodiment does not need to consider the deviation of the first relative position relationship and the deviation of the second relative position relationship, but can directly solve the kinematic parameter deviation, thereby improving the solution efficiency. It is more suitable for application scenarios with moderate requirements for the accuracy of the kinematic parameter deviation and high requirements for the speed of solving the kinematic parameter deviation. Among them, the second constraint equation constructed in this optional embodiment is the constraint relationship between the second position deviation of the end of the robot and the kinematic parameter deviation. The second position deviation represents the deviation between the actual position and the theoretical position of the end of the robot. In the process of determining the seventh relative position relationship, since the photos taken by the camera are used, the seventh relative position relationship can represent the actual position of the end of the robot. In the process of determining the third relative position relationship, the ideal kinematic parameters are used in the calculation, so the third relative position relationship can represent the theoretical position of the end of the robot.

[0071] In some embodiments of the present disclosure, the process of solving the second constraint equation can use the least squares method, introduce the second position deviation into the second constraint equation, and obtain the kinematic parameter deviation based on the least squares method. The calculation process is fast and efficient.

[0072] Through the above steps, it is possible to achieve the following: determining that the adapter plate is fixed to the end of the robot, wherein the calibration pin and the camera are fixed on the adapter plate, and the robot is fixed on the base; controlling the movement of the robot so that the calibration pin contacts the calibration plate, and obtaining a first relative position relationship between the calibration plate and the base; controlling the end to move toward the calibration point, and when the end moves to the calibration point, controlling the camera to take a photo, wherein the photo includes the calibration plate; determining the second relative position relationship between the camera and the base when taking the photo based on the photo and the first relative position relationship; determining the kinematic parameter deviation of the robot based on the second relative position relationship and the ideal kinematic parameters of the robot, thereby achieving the purpose of accurately determining the kinematic parameter deviation of the robot, thereby achieving the technical effect of efficiently and low-costly measuring the kinematic parameter deviation of the robot, and further solving the technical problems of high cost and low efficiency in the robot kinematic parameter calibration process.

[0073] Figure 3 is a schematic diagram of a parameter deviation determination tool provided according to some embodiments of the present disclosure. As shown in Figure 3, the parameter deviation determination tool may include: a camera, an adapter plate, a calibration pin and a calibration plate. The camera and the calibration pin are fixed on the adapter plate. The adapter plate can be fixed on the end of the robot, and the calibration plate is set to the following position: the robot movement is controlled so that the calibration pin can contact the position of the calibration plate. In order to prevent the camera from shifting relative to the adapter plate, a camera reinforcement tool can also be used to reinforce the connection between the camera and the adapter plate. Figure 4 is a schematic diagram of the coordinate system in the parameter deviation determination tool provided according to some embodiments of the present disclosure. As shown in Figure 4, {B} represents the base coordinate system, {TCP} represents the end coordinate system of the robot end, {C} represents the camera coordinate system, {T} represents the calibration pin coordinate system, {W} represents the calibration pin coordinate system, and {W} represents the calibration pin coordinate system. b} represents the calibration plate coordinate system.

[0074] The parameter deviation determination tooling provided in the embodiments of the present disclosure can efficiently determine the deviation of the robot's kinematic parameters. At the same time, the camera, adapter plate, calibration needle and calibration plate are all lightweight and easily available components. Therefore, the tooling has the advantages of low cost and easy portability, which makes it convenient for testers to carry it with them to the robot's operating site to calibrate the robot's kinematic parameter deviation.

[0075] Based on the parameter deviation determination tooling shown in FIG3 and FIG4 , the present disclosure provides the following optional embodiments for determining the kinematic parameters of the robot to be identified. FIG5 is a schematic diagram of a robot kinematic parameter identification process provided according to some embodiments of the present disclosure. As shown in FIG5 , the operating steps of this optional embodiment are as follows:

[0076] Step 1: Install the camera and calibration pin on the adapter plate. Then, install the adapter plate at the end of the robot. Place the calibration plate where the robot can reach it. For example, you can move the robot with the calibration pin at the end of the robot until the pin touches the calibration plate. Attach the camera's mounting tool and connect any cables.

[0077] Step 2: Set the calibration pin coordinate system {T} under the tool center point TCP in the robot control. That is, the position of the calibration pin coordinate system {T} is described under the robot end coordinate system {TCP}. Since the physical parameters (geometric parameters) of the calibration pin are known, the {T} coordinate system can be obtained directly.

[0078] Step 3: Operate the robot to determine the calibration plate coordinate system {W b The first teaching point is the origin of the calibration plate coordinate system P o ; The second teaching point is a point P on the X-axis direction of the calibration plate coordinate system x ; The third teaching point is a point P in the first quadrant of the XY plane of the calibration plate coordinate system xy.

[0079] The calibration plate coordinate system {W b The origin of the robot's base coordinate system {B} is P o ,{W b The x-axis of} is By vector cross multiplication we can get {W b}'s y and z axes:

[0080] So far, we have obtained the calibration plate coordinate system {W b}The description in the robot base coordinate system {B} is equivalent to determining the first relative position relationship.

[0081] Step 4: Set the camera coordinate system {C} in the robot control, that is, the description of the position of the camera coordinate system {C} in the robot's terminal coordinate system {TCP}. Since the physical parameters (geometric parameters) of the camera and adapter plate are known, this coordinate system can be directly obtained.

[0082] Step 5: Run the robot data acquisition program to automatically drive the robot to move the camera. The camera moves to the calibration point, captures an image of the calibration plate, and records the robot's joint positions at the time of the image capture via communication. This generates the first motion control parameters. After capturing the image at the last calibration point, the program sends a data acquisition completion signal to the robot controller.

[0083] Step 6: After receiving the data acquisition completion instruction, the robot kinematic parameter identification software relies on the robot kinematic error model to identify the actual kinematic parameters of the robot and sends a kinematic parameter identification completion instruction to the robot.

[0084] The process of establishing the kinematic error model is as follows:

[0085] 1. Robot kinematic modeling: To address the problem that the traditional DH modeling method (Denavit-Hartenberg modeling) cannot describe the deviation caused by assembly, processing, etc. when two adjacent joints are parallel, the present disclosure adopts an improved modeling method (Modified Denavit-Hartenberg modeling, abbreviated as M-DH modeling), which adds a rotation parameter β around the Y axis compared to the traditional DH modeling method.

[0086] In M-DH, the coordinate transformation from the link coordinate system {i-1} to the link coordinate system {i} can be achieved using the homogeneous transformation matrix

[0087] Where Trans(x i-1,a i-1 ) represents the direction along x i-1 Axis translation a i-1 ,Rot(x i-1 ,α i-1 ) represents the direction along x i-1 Axis rotation α i-1 ,Trans(z i ,d i ) represents the direction along z i Axis translation d i ,Rot(z i ,θ i ) represents the direction along z i Axis rotation θ i ,Rot(y i ,β i ) represents the direction along y i Axis rotation β i ,cθ i =cos(θ i ), sθ i = sin(θ i ), the rest of the symbols are similar.

[0088] From this we can get the robot forward kinematic model:

[0089] 2. Establishment of kinematic error model: The actual transformation relationship between two adjacent links of the robot can be obtained by using micro-translation and micro-rotation transformation Described as: In the formula is the actual transformation relationship between the two theoretical connecting rods, The differential homogeneous matrix between adjacent coordinate systems obtained by micro-translation and micro-rotation transformation:

[0090] The real kinematic model of the robot can be obtained as follows:

[0091] Expanding and simplifying the true kinematic model yields the constraint equation between the robot end position deviation and the robot kinematic parameter deviation (i.e., the second constraint equation):

[0092] where d n Indicates the deviation value of the robot's end position (i.e., the second position deviation):

[0093] Where P R is the actual position of the robot end (described in the base coordinate system, equivalent to the third relative position relationship); P Nis the theoretical end position of the robot (described in the base coordinate system, equivalent to the seventh relative position relationship), which can be calculated by the robot forward kinematics theory.

[0094] M a 、M α 、M d 、M θ 、M β The simplified 3×6 matrix is ​​the coefficient matrix of the robot's kinematic parameter deviations; Δa, Δα, Δd, Δθ, and Δβ refer to the parameter deviations of the robot's kinematic model, describing the translation error along the X axis, the rotation error around the X axis, the translation error along the Z axis, the rotation error around the Z axis, and the rotation error around the Y axis, respectively.

[0095] Δa=[Δa1 Δa2 Δa3 Δa4 Δa5 Δa6] T

[0096] Δα=[Δα1 Δα2 Δα3 Δα4 Δα5 Δα6] T

[0097] Δd=[Δd1 Δd2 Δd3 Δd4 Δd5 Δd6] T

[0098] Δθ=[Δθ1 Δθ2 Δθ3 Δθ4 Δθ5 Δθ6] T

[0099] Δβ=[Δβ1 Δβ2 Δβ3 Δβ4 Δβ5 Δβ6] T

[0100] Δa, Δα, Δd, Δθ, and Δβ are the kinematic parameter deviations of the robot.

[0101] This optional embodiment can also provide the following method for determining the kinematic parameter deviation, that is, the robot's calibration plate coordinate system {W b} error (i.e., the deviation of the first relative position relationship) and the error of the camera coordinate system {C} (i.e., the deviation of the second relative position relationship) are used as parameters to be identified to improve the accuracy of solving the kinematic parameter deviation. The actual {0} link coordinate system of the robot is in {W b} is described as follows:

[0102] The camera's actual {C} coordinate system is described in the actual link coordinate system {6} ({6} is the same as {TCP} above) as follows:

[0103] Then the pose transformation of the actual camera in the calibration plate coordinate system can be expressed as:

[0104] Assume that the theoretical position of the camera in the calibration plate coordinate system is (i.e. the fifth relative position relationship), the actual position of the camera in the calibration plate coordinate system is (i.e. the sixth relative position relationship), the deviation between the theoretical position and the actual position of the camera in the calibration plate coordinate system can be obtained (i.e. the first position deviation) is:

[0105] In the above formula, M Wb 、M C is the simplified 3×6 matrix, ΔW b is the deviation of the calibration plate coordinate system, and ΔC is the deviation of the camera coordinate system:

[0106] ΔC=[Δa C Δg C Δd C Δα C Δβ C Δθ C ] T

[0107] Where Δg is the position error in the Y-axis direction. The actual position of the camera in the calibration plate coordinate system It can be directly obtained by taking pictures with a camera. It can be calculated from the ideal kinematic parameters. Now we only need to solve the parameters to be identified [ΔW b Δa Δα Δd Δθ Δβ ΔC] T The obtained parameters are the deviation of the kinematic model to be identified, and thus the kinematic parameter deviation of the robot is obtained. Then, the real kinematic parameters of the robot are determined based on the ideal kinematic parameters of the robot, thereby improving the absolute accuracy of the robot.

[0108] The above-mentioned deviation process of solving the parameters to be identified can be determined by the least square method, and the process is as follows:

[0109] Let matrix

[0110] The parameter vector to be identified b=[ΔW b Δa Δα Δd Δθ Δβ ΔC] T ;

[0111] Multiple groups The error vector is e, then e=Ab, and the above formula can be directly solved by the least square method to obtain b, b=(A T A) -1 A T e.

[0112] The least squares method has high computational efficiency, but is greatly affected by data sampling errors. In order to further improve computational accuracy and reduce the impact of data sampling errors, the present disclosure can also use the overall least squares method to solve b.

[0113] The overall least squares method considers the errors of the dependent variable and the independent variable at the same time, handles the errors in the data more comprehensively, has a certain robustness to outliers, and can better adapt to data containing outliers.

[0114] FIG6 is a schematic diagram of a flow chart of a total least squares method solution according to some embodiments of the present disclosure. As shown in FIG6 , the specific flow of the total least squares method is as follows:

[0115] (1) Calculate the singular value decomposition (SVD) of the augmented matrix A and store the matrix V.

[0116] (2) Determine the number of main singular values ​​p, that is, use σ p >σ n+1 +ε>σ p+1 ≥…≥σ n+1 Determine p, where ε is a small positive number.

[0117] (3) Let V1 = [v p+1 v p+2 …v n+1 ] is the column-block matrix of V, and calculates the Householder transformation matrix Q such that: Here, α is a scalar and × represents a block whose value has no effect.

[0118] (4) If α≠0, calculate If α = 0, there is no overall least squares solution for the original setting p. p should be reduced, and the above steps should be repeated and recalculated until a unique overall least squares solution is found.

[0119] Step 7: After receiving the kinematic parameter identification completion instruction, the robot controller writes the identified kinematic parameters. This completes the kinematic parameter identification work.

[0120] In the above-mentioned optional embodiment, a camera is mounted on the end of the robot. The calibration plate coordinate system, the end coordinate system, and a preset program are used to drive the robot to carry the camera to the sampling point and take photos including the calibration plate. This process is equivalent to collecting the coordinate information necessary to identify the kinematic parameters. At the same time, the joint coordinate values ​​of the robot at the sampling point are recorded. Then, a robot kinematic error model is constructed based on micro-translation and micro-rotation transformations. The deviations of the robot's various kinematic parameters are obtained through the overall least squares method. Finally, the corrected robot kinematic parameters are written into the robot controller, thereby achieving the purpose of improving the robot's accuracy. The data sampling device in this optional embodiment is a visual 2D camera. This camera is low-cost and, in multiple experimental verifications, can effectively improve the absolute accuracy of the robot when combined with the method disclosed herein. At the same time, the camera data acquisition scheme ensures the need for non-contact data acquisition. Automated data acquisition can be completed only through the program, which is very efficient and does not rely on the operating skills of technicians.

[0121] The hardware components of this disclosure include a camera-robot adapter board, a 2D visual camera, and a visual calibration board. These components are compact and lightweight, making them highly portable. Extensive experiments have demonstrated that calibrating a six-axis collaborative robot takes only about 30 minutes, improving the robot's absolute accuracy by over 70%. Therefore, the solution provided by this disclosure offers the following technical benefits: non-contact data acquisition, low cost, portability, high efficiency, and high calibration accuracy.

[0122] Based on the above embodiments or optional embodiments provided by the present disclosure, the kinematic parameters of a six-degree-of-freedom collaborative robot were calibrated in order to verify the kinematic parameter correction effect. 50 verification points were collected from the calibrated robot using a laser tracker to verify the improvement in the absolute accuracy of the robot after calibration by this device. The verification method is as follows: The laser tracker can obtain the actual position P of the robot end through the target ball and the coordinate system change. R The laser tracker has a high precision and the position P R It can be considered as the real position of the robot end position. And through the robot kinematics calculation, the end position P before the robot kinematics parameter calibration can be obtained. B and the end position P after the robot kinematic parameters are calibrated A , then the absolute accuracy of the robot before calibration is E B =||P R -P B ||, the absolute accuracy of the robot after calibration is E A =||P R -P A ||, compared with E B With E A The calibration effect verification can be completed by adjusting the size of

[0123] FIG7 is a schematic diagram of the kinematic parameter accuracy verification result of the robot 1 according to an optional embodiment of the present disclosure. The final accuracy verification result of the robot 1 is shown in FIG7 . The calibrated curve in FIG7 represents the absolute accuracy E of the robot 1 after calibration by the device of the present disclosure. A1 The curve before calibration represents the absolute positioning accuracy E of robot 1 before calibration. B1 , unit: mm.

[0124] Calculate the average absolute accuracy Where E is the absolute accuracy of the robot at a single verification point, num p To verify the number of points, the final absolute accuracy of the robot 1 after calibration by the disclosed device is: E A_avg1 =0.743664 mm. The average absolute accuracy of the robot 1 without calibration by the disclosed device is: E B_avg1 Analyzing the above experimental data, the absolute accuracy of the robot 1 is improved by 96.8581% after the kinematic parameters of the robot are calibrated using the device and process proposed in the present disclosure.

[0125] FIG8 is a schematic diagram of the kinematic parameter accuracy verification results of the robot 2 according to an optional embodiment of the present disclosure. The final accuracy verification result of the robot 2 is shown in FIG8 . The robot 2 is calibrated by the device and process proposed in the present disclosure and the data is analyzed:

[0126] After calibration by the disclosed device, the absolute accuracy of robot 2 is: E A_avg2 =1.174933 mm, while the average absolute accuracy of the robot without calibration by the disclosed device is: E B_avg2 Analyzing the above experimental data, the absolute accuracy of robot 2 is improved by 76.55% after the kinematic parameters of the robot are calibrated using the device and process proposed in this disclosure.

[0127] The following table summarizes the improvement in absolute accuracy after calibrating the robot's kinematic parameters using the apparatus and process proposed in this disclosure.

[0128] Extensive experimental data has verified that the absolute accuracy of various robot models can be improved by 70% after calibrating their kinematic parameters using the device and process proposed in this disclosure. This achieves the high precision required for on-site calibration equipment. Calibrating a single robot using the device and process proposed in this disclosure takes approximately 30 minutes, meeting the high efficiency requirement. Camera photography is a non-contact measurement, meeting the requirement for non-contact data collection. The entire device is low-cost and compact, meeting the requirements for portability and low cost.

[0129] It should be noted that for the aforementioned method embodiments, for simplicity of description, they are all expressed as a series of action combinations, but those skilled in the art should be aware that the present disclosure is not limited by the order of the actions described, because according to the present disclosure, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions and components involved are not necessarily required by the present disclosure.

[0130] Through the description of the above embodiments, those skilled in the art can clearly understand that the parameter deviation determination method according to the above embodiment can be implemented by means of software plus a necessary general hardware platform, and of course it can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present disclosure, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, a magnetic disk, or an optical disk), and includes a number of instructions for enabling a terminal device (which can be a mobile phone, a computer, a server, or a network device, etc.) to execute the methods of the various embodiments of the present disclosure.

[0131] According to an embodiment of the present disclosure, a parameter deviation determination device for implementing the above-mentioned parameter deviation determination method is also provided. Figure 9 is a structural block diagram of the parameter deviation determination device provided according to an embodiment of the present disclosure. As shown in Figure 9, the parameter deviation determination device includes: a first determination component 91, a first control component 92, a second control component 93, a second determination component 94 and a third determination component 95. The parameter deviation determination device is described below.

[0132] A first determining component 91 is used to determine that the adapter plate is fixed to the end of the robot, wherein the calibration pin and the camera are fixed to the adapter plate, and the robot is fixed to the base;

[0133] A first control component 92 is connected to the first determination component 91 and is used to control the movement of the robot so that the calibration needle contacts the calibration plate to obtain a first relative position relationship between the calibration plate and the base;

[0134] The second control component 93 is connected to the first control component 92 and is used to control the end terminal to move toward the calibration point. When the end terminal moves to the calibration point, the camera is controlled to take a photo, wherein the photo includes the calibration plate;

[0135] A second determining component 94 is connected to the second control component 93 and is used to determine a second relative position relationship between the camera and the base when taking the photo based on the photo and the first relative position relationship;

[0136] The third determining component 95 is connected to the second determining component 94 and is used to determine the kinematic parameter deviation of the robot according to the second relative position relationship and the ideal kinematic parameters of the robot.

[0137] It should be noted that the first determination component 91, first control component 92, second control component 93, second determination component 94, and third determination component 95 described above correspond to steps S201 to S205 in the embodiment. The examples and application scenarios implemented by these components and corresponding steps are the same, but are not limited to the contents disclosed in the above embodiment. It should be noted that the above components, as part of the device, can be run in the computer terminal 10 provided in the embodiment.

[0138] An embodiment of the present disclosure may provide a computer device. Optionally, in this embodiment, the computer device may be located in at least one of a plurality of network devices in a computer network. The computer device includes a memory and a processor.

[0139] Among them, the memory can be used to store software programs and components, such as the program instructions / components corresponding to the parameter deviation determination method and device in the embodiment of the present disclosure, and the processor executes various functional applications and data processing by running the software programs and components stored in the memory, that is, realizing the above-mentioned parameter deviation determination method. The memory may include a high-speed random access memory, and may also include a non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some instances, the memory may further include a memory remotely arranged relative to the processor, and these remote memories can be connected to the computer terminal via a network. Examples of the above-mentioned network include but are not limited to the Internet, an intranet, a local area network, a mobile communication network and a combination thereof.

[0140] The processor can call the information and application stored in the memory through the transmission device to perform the following steps: determine that the adapter plate is fixed to the end of the robot, wherein the calibration pin and the camera are fixed on the adapter plate, and the robot is fixed on the base; control the movement of the robot so that the calibration pin contacts the calibration plate to obtain a first relative position relationship between the calibration plate and the base; control the end to move toward the calibration point, and when the end moves to the calibration point, control the camera to take a photo, wherein the photo includes the calibration plate; based on the photo and the first relative position relationship, determine the second relative position relationship between the camera and the base when taking the photo; based on the second relative position relationship and the ideal kinematic parameters of the robot, determine the kinematic parameter deviation of the robot.

[0141] A person skilled in the art will understand that all or part of the steps in the various methods of the above embodiments can be completed by instructing the hardware related to the terminal device through a program, and the program can be stored in a non-volatile storage medium, which may include: a flash drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, etc.

[0142] The embodiment of the present disclosure further provides a non-volatile storage medium. Optionally, in this embodiment, the non-volatile storage medium can be used to store the program code executed by the parameter deviation determination method provided in the above embodiment.

[0143] In some embodiments of the present disclosure, the non-volatile storage medium may be located in any computer terminal in a computer terminal group in a computer network, or in any mobile terminal in a mobile terminal group.

[0144] In some embodiments of the present disclosure, a non-volatile storage medium is configured to store program codes for executing the following steps: determining that an adapter plate is fixed to the end of the robot, wherein a calibration pin and a camera are fixed to the adapter plate, and the robot is fixed to a base; controlling the movement of the robot so that the calibration pin contacts the calibration plate to obtain a first relative position relationship between the calibration plate and the base; controlling the end to move toward the calibration point, and when the end moves to the calibration point, controlling the camera to take a photo, wherein the photo includes the calibration plate; determining a second relative position relationship between the camera and the base when taking the photo based on the photo and the first relative position relationship; determining the kinematic parameter deviation of the robot based on the second relative position relationship and the ideal kinematic parameters of the robot.

[0145] The serial numbers of the above-mentioned embodiments of the present disclosure are for description only and do not represent the advantages or disadvantages of the embodiments.

[0146] In the above embodiments of the present disclosure, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0147] In the several embodiments provided in this disclosure, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only exemplary. For example, the division of units can be a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, and the indirect coupling or communication connection of units or components can be electrical or other forms.

[0148] Units described as separate components may or may not be physically separate, and components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple units. Some or all of the units may be selected to achieve the purpose of the present embodiment according to actual needs.

[0149] In addition, the functional units in the various embodiments of the present disclosure may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0150] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a non-volatile storage medium. Based on this understanding, the technical solution of the present disclosure is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, server or network device, etc.) to execute all or part of the steps of the various embodiments of the present disclosure. The aforementioned storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, magnetic disk or optical disk and other media that can store program code.

[0151] The above is only a preferred embodiment of the present disclosure. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present disclosure. These improvements and modifications should also be regarded as within the scope of protection of the present disclosure. Industrial Applicability

[0152] The present invention is applied to the field of program control. In the disclosed embodiment, an adapter plate is fixed to the end of the robot, wherein the calibration pin and the camera are fixed on the adapter plate, and the robot is fixed on the base; the robot is controlled to move so that the calibration pin contacts the calibration plate, and a first relative position relationship between the calibration plate and the base is obtained; the end is controlled to move toward the calibration point, and when the end moves to the calibration point, the camera is controlled to take a photo, wherein the photo includes the calibration plate; based on the photo and the first relative position relationship, a second relative position relationship between the camera and the base when taking the photo is determined; based on the second relative position relationship and the ideal kinematic parameters of the robot, the kinematic parameter deviation of the robot is determined, thereby achieving the purpose of accurately determining the kinematic parameter deviation of the robot, thereby realizing the technical effect of efficiently and low-costly measuring the kinematic parameter deviation of the robot, and further solving the technical problems of high cost and low efficiency in the robot kinematic parameter calibration process and non-portability of the calibration equipment.

Claims

1. A method for determining parameter deviation, comprising: Determine that the adapter plate is fixed to the end of the robot, wherein a calibration needle and a camera are fixed to the adapter plate, and the robot is fixed to a base; Control the robot to move so that the calibration needle contacts the calibration plate, and obtain a first relative position relationship between the calibration plate and the base; Control the end to move towards the target point, and when the end moves to the target point, control the camera to take a photo, wherein the photo includes the calibration plate; Determine a second relative position relationship between the camera and the base when the photo is taken according to the photo and the first relative position relationship; Determine the kinematic parameter deviation of the robot according to the second relative position relationship and the ideal kinematic parameters of the robot.

2. The method according to claim 1, wherein The step of determining the kinematic parameter deviation of the robot according to the second relative position relationship and the ideal kinematic parameters of the robot includes: Obtain the camera physical parameters of the camera and the adapter plate physical parameters of the adapter plate; Obtain the first motion control parameter of the robot when the end moves to the target point; Determine a third relative position relationship between the end and the base when the photo is taken according to the first motion control parameter and the ideal kinematic parameters; Determine the kinematic parameter deviation according to the second relative position relationship, the third relative position relationship, the camera physical parameters and the adapter plate physical parameters.

3. The method according to claim 2, wherein, The step of determining the kinematic parameter deviation according to the second relative position relationship, the third relative position relationship, the camera physical parameters and the adapter plate physical parameters includes: Construct a forward kinematic model of the robot; Determine a first position deviation of the camera in the calibration plate coordinate system according to the first relative position relationship, the second relative position relationship, the third relative position relationship, the adapter plate physical parameters and the camera physical parameters; Determine a first constraint equation between the first position deviation and the parameter deviation to be identified according to the forward kinematic model, the adapter plate physical parameters and the camera physical parameters, wherein the parameter deviation to be identified includes: the kinematic parameter deviation, the deviation of the first relative position relationship, and the deviation of the position relationship between the camera and the end; Solve the first constraint equation according to the first position deviation to obtain the parameter deviation to be identified; Determine the kinematic parameter deviation according to the parameter deviation to be identified.

4. The method according to claim 3, wherein, The step of determining the first position deviation of the camera in the calibration plate coordinate system according to the first relative position relationship, the second relative position relationship, the third relative position relationship, the adapter plate physical parameters and the camera physical parameters includes: Determine a fourth relative position relationship between the end and the calibration plate when the photo is taken according to the first relative position relationship and the third relative position relationship; Determine a fifth relative position relationship between the camera and the calibration plate when the photo is taken according to the fourth relative position relationship, the adapter plate physical parameters and the camera physical parameters; Determine a sixth relative position relationship between the camera and the calibration board when the photo is taken according to the photo; Determine the first position deviation according to the deviation between the fifth relative position relationship and the sixth relative position relationship.

5. The method according to claim 3, wherein, Solving the first constraint equation according to the first position deviation to obtain the deviation of the parameter to be identified includes: Substitute the first position deviation into the first constraint equation to obtain an equation to be solved; Solve the equation to be solved by using the total least squares method to obtain the deviation of the parameter to be identified.

6. The method according to claim 2, wherein, Determine the deviation of the kinematic parameter according to the second relative position relationship, the third relative position relationship, the physical parameters of the camera and the physical parameters of the adapter plate, including: Construct a forward kinematic model of the robot; Determine a seventh relative position relationship between the end effector and the base when the photo is taken according to the second relative position relationship, the physical parameters of the camera and the physical parameters of the adapter plate; Determine a second position deviation of the end effector according to the deviation between the third relative position relationship and the seventh relative position relationship; Determine a second constraint equation between the second position deviation and the deviation of the kinematic parameter according to the forward kinematic model; Solve the second constraint equation according to the second position deviation to obtain the deviation of the kinematic parameter.

7. The method according to any one of claims 1 to 6, wherein Control the movement of the robot so that the calibration needle contacts the calibration board to obtain a first relative position relationship between the calibration board and the base, including: Obtain the physical parameters of the adapter plate of the adapter plate and the physical parameters of the calibration needle of the calibration needle; Control the movement of the robot so that the calibration needle contacts the calibration board, and record the second motion control parameters of the robot; Determine the first relative position relationship according to the second motion control parameters, the physical parameters of the calibration needle and the physical parameters of the adapter plate.

8. The method according to claim 7, wherein Controlling the movement of the robot so that the calibration needle contacts the calibration board and recording the second motion control parameters of the robot includes: selecting a plurality of position points on the calibration board; controlling the movement of the robot so that the calibration needle contacts the plurality of position points respectively, and recording the respective corresponding second motion control parameters when the calibration needle contacts the plurality of position points respectively; Determining the first relative position relationship according to the second motion control parameters, the physical parameters of the calibration needle and the physical parameters of the adapter plate includes: determining an eighth relative position relationship between the end effector and the base when the calibration needle contacts the plurality of position points respectively according to the second motion control parameters; determining a ninth relative position relationship between the calibration needle and the base when the calibration needle contacts the plurality of position points respectively according to the eighth relative position relationship, the physical parameters of the calibration needle and the physical parameters of the adapter plate; determining the first relative position relationship according to the ninth relative position relationship.

9. A device for determining parameter deviation, comprising: The first determination component is configured to determine that the adapter plate is fixed to the end of the robot. Among them, the calibration needle and the camera are fixed to the adapter plate, and the robot is fixed to the base; The first control component is configured to control the movement of the robot so that the calibration needle contacts the calibration plate to obtain a first relative position relationship between the calibration plate and the base; The second control component is configured to control the end to move towards the calibration point. When the end moves to the calibration point, control the camera to take a photo, where the photo includes the calibration plate; The second determination component is configured to determine a second relative position relationship between the camera and the base when the photo is taken according to the photo and the first relative position relationship; The third determination component is configured to determine the kinematic parameter deviation of the robot according to the second relative position relationship and the ideal kinematic parameters of the robot.

10. A parameter deviation determination tooling, comprising: A camera, an adapter plate, a calibration needle and a calibration plate; among them, the camera and the calibration needle are fixed to the adapter plate, the adapter plate is fixed to the end of the robot, and the calibration plate is arranged at the following position: control the movement of the robot so that the calibration needle can contact the calibration plate.

11. A non-volatile storage medium, the non-volatile storage medium including a stored program, wherein, When the program runs, control the device where the non-volatile storage medium is located to execute the parameter deviation determination method according to any one of claims 1 to 8.

12. A computer device, the computer device comprising a memory and a processor, the memory being used for storing programs, and the processor being used for running the programs stored in the memory, wherein, When the program runs, execute the parameter deviation determination method according to any one of claims 1 to 8.

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