Industrial robot calibration device and method based on one-dimensional distance error model

Abstract

The application discloses a kind of industrial robot calibration device and method based on one-dimensional distance error model, belongs to industrial robot calibration technical field, and calibration device includes laser interferometer, slide rail assembly, interference mirror assembly, mirror assembly and 45 ° refracting mirror, slide rail assembly is formed by 3 slide rails and is spliced into composite structure, x-y plane movement and z-axis direction adaptation are realized, and mirror assembly contains telescopic rod and inner layer movable slider to ensure continuous optical path;Calibration method is established kinematics and error model by DH method, off-line planning one-dimensional movement path, the actual distance of adjacent points is measured using calibration device, error parameters are identified based on one-dimensional distance error model combined with damped least square method, and finally error compensation is completed.The application simplifies optical path adjustment, improves measurement efficiency and identification accuracy, is low in cost and portable, and the precision of industrial robot after compensation can be improved by more than 70%.

Description

Technical Field

[0001] This invention belongs to the field of industrial robot calibration technology, and in particular relates to an industrial robot calibration device and method based on a one-dimensional distance error model. Background Technology

[0002] Currently, industrial robots are widely used in material handling, machine loading and unloading, spot welding, arc welding, cutting, assembly, testing, inspection, gluing, grinding, and polishing. While industrial robots currently offer high repeatability, their absolute positioning accuracy is relatively low, making it difficult to meet the precision requirements of some fields. To improve the absolute positioning accuracy of industrial robots, calibration methods can be used to identify their accurate parameters. This process mainly includes four steps: error modeling, pose measurement, parameter identification, and error compensation.

[0003] Commonly used industrial robot calibration instruments include laser trackers, wire encoders, and ballbars.

[0004] Laser trackers are high-precision three-dimensional coordinate measurement systems based on laser interferometric ranging and angle measurement technology. However, the error of their angle encoders amplifies the error, significantly reducing the accuracy of the transformed three-dimensional coordinates. The measurement error of wire encoders accumulates with the extension and bending of the wire, making them sensitive to minute wire movements or vibrations, which can lead to fluctuations and instability in the measurement results. The Renishaw QC20-W dual ballbar has a measuring range of only ±1mm, making it unsuitable for measuring industrial robots with low precision requirements. Invention patent CN119901206B, a position error calibration device and method for industrial robots, proposes a position error calibration device composed of a laser interferometer, beam splitter, two-dimensional position sensitive detector, and two-dimensional moving platform. This device can directly measure the three-dimensional coordinates of the end effector target ball of the industrial robot, meeting the calibration requirements of industrial robots. However, this position error calibration device has a relatively complex structure, requiring sensors such as two-dimensional position sensitive detectors and grating rulers, resulting in high costs.

[0005] Therefore, it is essential to develop an industrial robot calibration device and method that is simple in structure, highly efficient in measurement, highly accurate, and low in cost. Summary of the Invention

[0006] The problem this invention aims to solve is to provide an industrial robot calibration device and method based on a one-dimensional distance error model, which identifies the kinematic parameter errors of an industrial robot by measuring the actual distance of its end effector and comparing it with the theoretical distance.

[0007] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: an industrial robot calibration device based on a one-dimensional distance error model, including a laser interferometer, a slide rail assembly, an interferometer assembly, a reflector assembly, and a 45° refraction mirror;

[0008] The slide rail assembly includes a horizontal guide rail and a vertical guide rail. The vertical guide rail is vertically mounted on the horizontal guide rail and is slidably connected to the horizontal guide rail via a slider, allowing the vertical guide rail to slide laterally. This enables free movement within the xy-plane, allowing for measurements at different positions within the xy-plane. Simultaneously, it ensures excellent coaxiality of the height of each component, significantly reducing the time required for optical path adjustment. The vertical guide rail includes a horizontal portion and a flip-up portion, which are hinged together to form a tilting and bending mechanism.

[0009] The laser interferometer is installed at the end of the horizontal section of the vertical guide rail, with its laser emission port facing the interferometer assembly to ensure that the laser can be directly incident on the interferometer.

[0010] The interferometer assembly is mounted on the horizontal part of the vertical guide rail by a slider. The interferometer assembly is located between the laser interferometer and the reflector assembly. The laser emitted by the laser interferometer can be accurately pointed to the reflector assembly after being refracted by the interferometer assembly.

[0011] The reflector assembly is mounted on the flip-out part of the vertical guide rail to solve the problem of optical path interruption caused by non-measurement direction errors during measurement;

[0012] The reflector assembly includes a reflector, an adjusting slider, an inner movable slider, and a telescopic rod. The adjusting slider has a groove at its bottom that mates with a vertical guide rail, allowing it to move along the direction of the vertical guide rail. An inner movable slider is mounted on top of the adjusting slider, and this inner movable slider can move perpendicular to the vertical guide rail. The telescopic rod is fixedly mounted on the inner movable slider, and its top end is rigidly connected to the end effector of the industrial robot being measured. The reflector is mounted on the adjusting slider facing the direction of the interferometer assembly.

[0013] The inner movable slider is equipped with a fixing hole that matches the telescopic rod. When measuring the x-axis, if the end effector of the industrial robot shifts in the y-axis or z-axis direction due to positional error, the telescopic rod can extend and retract, and the inner movable slider can slide along the vertical guide rail 23 to ensure that the reflector is always aligned with the optical path of the interferometer assembly, avoiding optical path interruption caused by y-axis or z-axis offset.

[0014] A 45° refracting mirror is also provided on the horizontal part of the vertical guide rail. The 45° refracting mirror is only used when measuring the z-axis. When the flip-out part of the vertical guide rail is flipped 90° (for z-axis measurement), the horizontal laser emitted by the laser interferometer is reflected by the 45° refracting mirror and converted into a vertical laser, which points to the reflector assembly, thus achieving optical path matching in the z-axis direction.

[0015] Furthermore, the transverse guide rail includes a first transverse guide rail and a second transverse guide rail, which are arranged in parallel.

[0016] Furthermore, the flip-out portion can be flipped 90°, and the flip-out portion after flipping can be adapted to measurement in the z-axis direction.

[0017] Furthermore, the telescopic rod is a telescopic metal rod with a telescopic range of ±5mm.

[0018] Meanwhile, this invention proposes a method based on a one-dimensional distance error model, using a laser interferometer to measure and obtain the one-dimensional distance of the industrial robot, and combining this with the damped least squares method to identify the error parameters of the industrial robot.

[0019] An industrial robot calibration method based on a one-dimensional distance error model includes the following steps:

[0020] S1. Establish the kinematic and error models of the industrial robot based on the DH method.

[0021] S2. Plan the movement path of the industrial robot in one-dimensional directions of x-axis, y-axis, and z-axis, install this calibration device, drive the industrial robot to move at intervals l, record the laser interferometer readings, calculate the actual movement distance between two adjacent points of the industrial robot, and complete multi-position and multi-directional measurements by moving or flipping the slide rail assembly.

[0022] S3. Based on the squared distance between adjacent points of the command trajectory and the actual trajectory, a one-dimensional distance error model is established. The model calculates the relationship between the measurement axis direction error by separating the Jacobian matrix of each axis.

[0023] S4. Use the damped least squares method to identify error parameters, and adjust the damping coefficient μ to achieve adaptive iterative optimization until the accuracy requirements are met.

[0024] S5. Substitute the identified error parameters into the kinematic model to complete the error compensation.

[0025] The beneficial effects of this invention are as follows:

[0026] (1) This invention ensures the coaxiality of the optical path, and distance measurements at different positions can be performed using a laser interferometer and a movable slide rail assembly. It ensures that the laser interferometer accurately receives the refracted light, enabling the measurement of distance errors in the three vertical directions (x-axis, y-axis, and z-axis) of the industrial robot without repeated adjustments to the optical path. The slide rail assembly fulfills the requirement that the laser interferometer, interferometer, and reflector be on the same axis. The design of the telescopic rod and inner movable slider of the reflector assembly prevents errors in the other two directions from affecting the measurement in that direction.

[0027] (2) The present invention sets the Jacobian matrix of the other two axes to zero to ensure consistency with the actual measurement direction and improve the identification accuracy.

[0028] In summary, this invention utilizes the high measurement accuracy of a laser interferometer to develop a calibration device that is easy to manufacture, operate, carry, and has a large measurement range. It retains the high linearity of the laser interferometer while avoiding the cumbersome optical path adjustment, simplifying the adjustment process, improving measurement efficiency, facilitating multiple measurements at different positions within the industrial robot's workspace, and reducing costs. To meet the one-dimensional measurement requirements of the laser interferometer, the distance error model is made one-dimensional to avoid the influence of errors in the other two axes on identification. Simultaneously, using the distance error model avoids errors between the industrial robot's base coordinate system and the tool coordinate system, significantly improving identification accuracy. Attached Figure Description

[0029] The present invention will be described in detail below with reference to the accompanying drawings and examples. The advantages and implementation methods of the present invention will become more apparent from this description. The accompanying drawings are for illustrative purposes only and do not constitute any limitation on the present invention. In the accompanying drawings:

[0030] Figure 1 This is a schematic diagram of the structure of the present invention.

[0031] Figure 2 This is a diagram showing the z-axis measurement state of the slide rail assembly after it has been flipped.

[0032] Figure 3 This is a schematic diagram of the reflector assembly structure of the present invention.

[0033] In the picture:

[0034] 1. Laser interferometer; 2. Slide rail assembly; 3. Interferometer assembly; 4. Reflector assembly; 5. 45° refractor; 21. First transverse guide rail; 22. Second transverse guide rail; 23. Vertical guide rail; 41. Reflector; 42. Adjusting slider; 43. Inner movable slider; 44. Telescopic rod; 231. Horizontal part; 232. Flip-up part. Detailed Implementation

[0035] like Figures 1 to 3 As shown, the industrial robot calibration device based on a one-dimensional distance error model includes a laser interferometer 1, a slide rail assembly 2, an interferometer assembly 3, a reflector assembly 4, and a 45° refractor 5.

[0036] The slide rail assembly 2 is the basic carrier of the calibration device, including a first horizontal guide rail 21 (x-axis direction), a second horizontal guide rail 22 (x-axis direction), and a vertical guide rail 23 (y-axis direction). The first horizontal guide rail 21 and the second horizontal guide rail 22 are arranged parallel to each other, and the vertical guide rail 23 is vertically mounted on the first horizontal guide rail 21 and the second horizontal guide rail 22. The vertical guide rail 23 is slidably connected to the first horizontal guide rail 21 and the second horizontal guide rail 22 through a slider, allowing the vertical guide rail 23 to slide laterally. This constitutes a degree of freedom of movement in the xy plane, enabling measurements to be taken at different positions in the xy plane. At the same time, it can effectively ensure the coaxiality of the height of each component, greatly reducing the time for optical path adjustment. The vertical guide rail 23 includes a horizontal part 231 and a flip-up part 232. The horizontal part 231 and the flip-up part 232 are hinged to form a flipping mechanism, which can be flipped 90°. After flipping, the flip-up part 232 can be adapted for measurement in the z-axis direction.

[0037] As can be seen, the slide rail assembly 2 consists of three slide rails forming a two-degree-of-freedom slide rail, which can realize the distance measurement of the x and y axes at different positions on the same plane. At the same time, a flip-up design is added to meet the measurement of the movement distance on the z axis.

[0038] The laser interferometer 1 is mounted and fixed at the end of the horizontal portion 231 of the vertical guide rail 23. The laser emission port of the laser interferometer 1 faces the interferometer assembly 3 to ensure that the laser can be directly shone onto the interferometer.

[0039] The interferometer assembly 3 is mounted on the horizontal portion 231 of the vertical guide rail 23 via a slider. The interferometer assembly 3 is located between the laser interferometer 1 and the reflector assembly 4. The laser emitted by the laser interferometer 1 can be accurately pointed to the reflector assembly 4 after being refracted by the interferometer assembly 3.

[0040] The reflector assembly 4 is mounted on the flip-out portion 232 of the vertical guide rail 23 to solve the problem of optical path interruption caused by non-measurement direction errors during measurement. The reflector assembly 4 includes a reflector 41, an adjusting slider 42, an inner movable slider 43, and a telescopic rod 44. The bottom of the adjusting slider 42 is provided with a groove that cooperates with the vertical guide rail 23, and it can move along the direction of the vertical guide rail 23. The top of the adjusting slider 42 is equipped with the inner movable slider 43, which can move along the direction perpendicular to the vertical guide rail 23. The telescopic rod 44 is mounted and fixed on the inner movable slider 43. The telescopic rod 44 is a telescopic metal rod (telescopic range ±5mm), and its top end is rigidly connected to the end effector of the industrial robot being measured. The reflector 41 is mounted on the adjusting slider 42 in the direction facing the interferometer assembly 3.

[0041] The inner movable slider 43 is provided with a fixing hole that matches the telescopic rod 44. When measuring the x-axis, if the end effector of the industrial robot shifts in the y-axis or z-axis direction due to positional error, the telescopic rod 44 can extend and retract, and the inner movable slider 43 can slide along the vertical guide rail 23 to ensure that the reflector 41 is always aligned with the optical path of the interferometer assembly 3, thus avoiding optical path interruption caused by y-axis or z-axis offset.

[0042] It is evident that the telescopic rod 44 and the inner movable slider 43 primarily increase the degrees of freedom of the industrial robot's end effector, preventing errors in the other two directions from affecting the measurement in that direction. When measuring the distance the industrial robot moves along the x-axis, the degrees of freedom of the telescopic rod 44 and the inner movable slider 43 ensure that regardless of errors in the y-axis and z-axis, the reflector 41 can receive the light path and accurately measure the distance the end effector moves only along the x-axis. Similarly, the same principle applies when measuring the distances moved along the y and z axes.

[0043] A 45° refracting mirror 5 is also provided on the horizontal part 231 of the vertical guide rail 23. The 45° refracting mirror 5 is only used when measuring the z-axis. When the flip-out part 232 of the vertical guide rail 23 is flipped 90° (for z-axis measurement), the horizontal laser emitted by the laser interferometer 1 is reflected by the 45° refracting mirror 5 and converted into a vertical laser, pointing towards the reflector assembly 4, thereby achieving optical path matching in the z-axis direction.

[0044] Meanwhile, the distance error model is improved by proposing a one-dimensional distance error model. A laser interferometer is used to measure the distance of the industrial robot in one dimension, and the error parameters of the industrial robot are identified by combining the damped least squares method.

[0045] An industrial robot calibration method based on a one-dimensional distance error model includes the following steps:

[0046] S1. Establish the forward kinematics model and error model of the industrial robot according to the DH method. The industrial robot used is the IRB-120 as an example, and the parameters of the industrial robot are shown in Table 1.

[0047] Table 1 DH Parameters of ABBIRB120 Robot

[0048]

[0049] At this point, the homogeneous transformation matrix of the adjacent joints of the industrial robot is:

[0050]

[0051] =

[0052] In the formula, i (i = 1, 2, ..., 6) is the joint number; θ i d is the joint angle; i This is the link offset; a i α is the length of the connecting rod; i This is the torsion angle of the connecting rod.

[0053] Multiplying the transformation matrices of each joint in sequence, we can obtain the homogeneous transformation matrix of the industrial robot's end effector coordinate system relative to the base coordinate system as follows:

[0054]

[0055] In the formula, Indicates the end-effector attitude. Indicates the end position

[0056] The kinematic model of an industrial robot can be expressed as a function of joint rotation angles, link offsets, link lengths, and link torsional angles. That is:

[0057]

[0058] There is a certain error between the theoretical and actual values ​​of the joint parameters of an industrial robot, namely Δθ. i Δd i , Δa i ,Δα i The actual kinematic model including parameter errors can be represented as:

[0059]

[0060] S2. Using offline programming, the movement path of the industrial robot in one dimension (x-axis, y-axis, z-axis) is planned, ensuring that the distance of the robot's movement interval is a constant value l. When measuring along the z-axis, a 45° refractor 5 needs to be installed to change the propagation path of the light. The calibration device is placed within the working range of the industrial robot, and the end effector of the industrial robot is connected to the telescopic rod 44 of the reflector assembly 4. Fine adjustments are made to the calibration device and its components to ensure that the end effector of the industrial robot, the reflector 41, the interferometer of the interferometer assembly 3, and the laser interferometer 1 have a certain degree of coaxiality during movement. Finally, the pitch and yaw angles of the laser interferometer 1 are adjusted using knobs so that the laser interferometer 1 can receive the reflected light, thus completing the light adjustment work of the calibration device.

[0061] First, the distance error on the x-axis is measured to drive the industrial robot to move. When the robot moves a fixed distance l, the data from the laser interferometer 1 (the distance between point j and point j+1) is read and recorded. By moving the entire vertical guide rail 23, the distance error on the x-axis at different positions in the plane is measured. Second, when measuring the y-axis, the entire device needs to be rotated 90° to make the vertical guide rail 23 parallel to the y-axis of the industrial robot. Then, by moving the vertical guide rail 23 in parallel, the distance error on the y-axis at different positions in the plane is measured. Finally, when measuring the z-axis, the flippable part 232 of the vertical guide rail 23 is flipped by 90°. The above operations are repeated to obtain a total of j sets of data.

[0062] The difference between the actual distance and the theoretical distance of the industrial robot under the commanded trajectory can be obtained:

[0063]

[0064] In the formula l R , l represents the actual trajectory distance and the theoretical trajectory distance from point j to point j+1, respectively.

[0065] S3. Based on the squared distance between adjacent points of the command trajectory and the actual trajectory, a one-dimensional distance error model is established. The model separates the Jacobian matrices of each axis and only calculates the relationship between the measurement axis direction errors. The distance error is introduced to characterize the accuracy of the industrial robot, which can avoid the coordinate transformation between the aforementioned measurement coordinate system and the industrial robot coordinate system.

[0066] Let the coordinates of any point on the commanded trajectory of the industrial robot be denoted as . , , (j=1, 2, 3…n, j is the number of points on the industrial robot's movement path). The expression for the squared distance between two adjacent points on the industrial robot's command trajectory is:

[0067]

[0068] In the formula, It is represented as the square of the distance from point j to point j+1 in the instruction trajectory.

[0069] The coordinates of the actual trajectory points of an industrial robot under the same command trajectory are: , , .

[0070] The expression for the squared distance between two adjacent points on the actual trajectory of the industrial robot is:

[0071]

[0072] In the formula, It is represented as the square of the distance from point j to point j+1 in the actual trajectory.

[0073] Based on the kinematic model and the distance error model, the relationship between the actual distance and the theoretical distance between two adjacent points is established:

[0074]

[0075] In the formula, J represents the deviation between the actual and theoretical distances between two adjacent points on the commanded trajectory of an industrial robot. j Let J be the Jacobian matrix when the end effector of the industrial robot is at point j. This refers to the kinematic parameter error of the industrial robot.

[0076] Currently, only straight-line distances are measured, i.e., distances along the x, y, and z axes. The distance model can be further specialized to a model based on a specific axis. When measuring only the distance an industrial robot travels along the y-axis, there is...

[0077]

[0078] The new distance error model is then expressed as:

[0079]

[0080] The Jacobian matrix J describes the relationship between joint rotational speed and end-effector Cartesian velocity and angular velocity. The Jacobian matrix is ​​obtained through differential transformation as follows:

[0081]

[0082] Substituting the above Jacobian matrix into... In, that is:

[0083]

[0084]

[0085] The above is a one-dimensional distance error model, which solves the errors generated on the three axes separately from the Jacobian matrices of the three axes. When measuring the error on the y-axis, the Jacobian matrix of the industrial robot's y-axis is calculated. The error generated on the y-axis is calculated with its Jacobian matrix. When enough measurement points are taken, the kinematic parameter errors of the industrial robot can be accurately identified.

[0086] S4. To improve the accuracy of identification and more comprehensively describe the kinematic error parameters of the industrial robot, data is also measured on the x-axis and z-axis of the industrial robot. The damped least squares method is used to identify the error parameters. Adaptive iterative optimization is achieved by adjusting the damping coefficient μ until the accuracy requirements are met. The formula is:

[0087]

[0088] In the formula, x k J is the value of the kth iteration. k Substitute x each time k The desired Jacobian matrix, Substitute x each time k The calculated value between two adjacent points Distance from actual distance The difference is calculated by continuously adjusting the damping coefficient μ (typically μ = 0.001) to obtain an adaptive step size until the optimal value x is obtained. k The algorithm flow is as follows:

[0089] Will The error parameter in the middle is x k The kinetic model obtained after substitution:

[0090]

[0091] In the formula, Indicates the end-effector attitude. Indicates the end position

[0092] Obtain the end-effector position value at any point after robot correction. , , Substitution

[0093] Calculate the corrected distance Then the error function is:

[0094]

[0095] The identification of the error value after iteration is specifically divided into four steps:

[0096] (1) Find the initial value, first use Obtain the initial error parameter solution ,Will Assign it to x1, then substitute the value of x1 back into the equation. In the process, find a new Jacobian matrix J1, since the initial value x1 is obtained through... It is easy to find that the damping coefficient μ0 (taken as 0.001) has an allowable error value. ;

[0097] (2) Iterate, substituting the above values ​​into In the middle, calculate x k+1 ; will x k Substitute into the kinematic model to calculate the error function ;

[0098] (3) If < Then it is x k If the optimal solution is found, exit the program; otherwise, calculate the new error function. ;

[0099] (4) Determine if convergence has occurred; if < Then let ;otherwise Recalculate the error parameter vector x k+1 Correct the kinematic parameters; re-enter the iteration until... The iteration stops when the accuracy requirement is met.

[0100] S5. Error compensation: The identified error parameters are input into the kinematic model to correct the original kinematic model, thereby improving the end effector accuracy of the industrial robot.

[0101] The output identifies parameter errors, including some unidentifiable parameters. Based on the forward kinematics equations, it is found that θ6 and α6 are only related to the end effector's rotational attitude and not to its position. In T=F(θ,d,a,α), the partial derivative of F with respect to d1 is a series of constants, thus J... j -J j+1 The corresponding column is always 0, indicating an ill-conditioned condition, therefore d1 is also an unidentifiable parameter. To verify reliability, a set of kinematic errors was set, and simulation calculations were performed using MATLAB. The final identified results show that the accuracy of the industrial robot can be improved by more than 70% after compensation.

[0102] Table 2 Simulation Comparison of Joint Identification Results

[0103]

[0104] This invention can, to a certain extent, avoid the influence of errors caused by actual measurement data. The simulation mimics actual measurement conditions, adding 10% noise to the data for interference. The identification results are shown in Table 3.

[0105] Table 3. Identification results after adding 10% noise to the data for interference.

[0106]

[0107] Conclusion: As can be seen from the table above, adding a certain amount of random error does not affect the identification results, indicating that this method has a certain degree of anti-interference capability.

[0108] The embodiments of the present invention have been described in detail above, but the content described is only a preferred embodiment of the present invention and should not be considered as limiting the scope of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the present invention.

Claims

1. An industrial robot calibration device based on a one-dimensional distance error model, characterized in that: The system includes a laser interferometer, a slide rail assembly, an interferometer assembly, a reflector assembly, and a 45° refractor. The slide rail assembly comprises a horizontal guide rail and a vertical guide rail. The vertical guide rail is vertically mounted on the horizontal guide rail and is slidably connected to the horizontal guide rail via a slider. The vertical guide rail includes a horizontal portion and a rotatable portion, which are hinged to form a turning mechanism. The laser interferometer is mounted at the end of the horizontal portion of the vertical guide rail, with its laser emission port facing the interferometer assembly. The interferometer assembly is mounted on the horizontal portion of the vertical guide rail via a slider. This interferometer assembly is located between the laser interferometer and the reflector assembly. The laser emitted by the laser interferometer is refracted by the interferometer assembly and points towards the reflector assembly. The reflector assembly is mounted on the rotatable portion of the vertical guide rail. The reflector assembly includes a reflector, an adjusting slider, an inner movable slider, and a telescopic rod. The adjusting slider has a groove at its bottom that mates with a vertical guide rail, allowing it to move along the direction of the vertical guide rail. An inner movable slider is mounted on top of the adjusting slider, and this inner movable slider moves perpendicular to the vertical guide rail. The telescopic rod is fixed to the inner movable slider, and its top end is rigidly connected to the end effector of the industrial robot being measured. The reflector is mounted on the adjusting slider facing the interferometer assembly. A 45° refractor is also provided on the horizontal portion of the vertical guide rail. This 45° refractor is only used when measuring the z-axis. When the flip-out portion of the vertical guide rail is rotated 90°, the horizontal laser emitted by the laser interferometer is reflected by the 45° refractor and converted into a vertical laser beam, pointing towards the reflector assembly, thus achieving optical path matching in the z-axis direction.

2. The industrial robot calibration device based on a one-dimensional distance error model according to claim 1, characterized in that: The transverse guide rail includes a first transverse guide rail and a second transverse guide rail, which are arranged in parallel.

3. The industrial robot calibration device based on a one-dimensional distance error model according to claim 1, characterized in that: The telescopic rod is a telescopic metal rod.

4. An industrial robot calibration method based on a one-dimensional distance error model, implemented using the industrial robot calibration device based on a one-dimensional distance error model as described in any one of claims 1 to 3, characterized in that: Includes the following steps: S1. Establish the kinematic and error models of the industrial robot based on the DH method; S2. Plan the movement path of the industrial robot in one-dimensional directions of x-axis, y-axis, and z-axis, install this calibration device, drive the industrial robot to move at intervals l, record the laser interferometer readings, calculate the actual movement distance between two adjacent points of the industrial robot, and complete multi-position and multi-directional measurements by moving or flipping the slide rail assembly. S3. Based on the squared distance between adjacent points of the command trajectory and the actual trajectory, a one-dimensional distance error model is established. The model calculates the relationship between the measurement axis direction error by separating the Jacobian matrix of each axis. S4. Use the damped least squares method to identify error parameters, and adjust the damping coefficient μ to achieve adaptive iterative optimization until the accuracy requirements are met. S5. Substitute the identified error parameters into the kinematic model to complete the error compensation.

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