Assembly error compensation method and system for robot with external expansion shaft

Abstract

The invention is suitable for the technical field of robots, and provides an assembly error compensation method and system for a robot with an external expansion shaft, and the method comprises the steps: obtaining a first space position and a second space position of a robot body, and a first joint angle and a second joint angle of a target external expansion shaft based on a preset position; based on the first spatial position, the first joint angle, the second spatial position and the second joint angle, the assembly error rate of the target external expansion shaft is determined; the initial joint angle of the target external expansion shaft and the target position of the robot body are obtained, and the target joint angle of the target external expansion shaft is determined; based on the initial joint angle, the target joint angle and the assembly error rate, target position deviation is determined; and the target position is corrected based on the target position deviation, and the final joint angle of the robot body is determined based on the corrected target position, so that the assembly error of the external expansion shaft is eliminated, and the positioning precision of the robot is improved.

Description

Technical Field

[0001] This application belongs to the field of robotics technology, and in particular relates to a method and system for compensating assembly errors of a robot with an external extension axis. Background Technology

[0002] In many industrial applications, robots alone often struggle to cover the entire task space. To extend the robot's working range to meet practical application needs, it is typically necessary to configure external extension axes. Depending on the specific application scenario, these external extension axes can be configured along different coordinate axes of the robot.

[0003] However, during the assembly of the robot body and the external extension axis, installation errors often make it difficult to ensure that the external extension axis is perfectly parallel and aligned with the robot's coordinate axes. This installation deviation directly affects the measurement accuracy of the eye-to-hand vision system, thus accumulating errors in the overall positioning accuracy of the robot's vision system. For example, in an eye-to-hand configuration, a vision sensor is installed at the robot's end effector. The vision sensor first identifies and locates the target position based on feature information, and the robot executes movement based on visual feedback to reach that target position. In actual operation, assuming the external extension axis is at the first joint angle during the visual positioning phase, when the robot moves to the target position, due to factors such as workspace interference, travel limits, or obstacle avoidance, the external extension axis needs to switch to the second joint angle. However, due to the assembly error caused by the external extension axis not being perfectly parallel and aligned with the robot's coordinate axes, the target point identified by the vision system and the actual point reached by the robot are not the same in physical space, resulting in a positioning deviation.

[0004] Therefore, how to eliminate assembly errors of the robot's external extension axis in order to improve the positioning accuracy of robots with external extension axes has become an urgent problem to be solved. Summary of the Invention

[0005] To solve at least one of the above-mentioned technical problems, eliminate assembly errors of the robot's external extension axis, and improve the positioning accuracy of the robot with the external extension axis, this application proposes a method and system for compensating assembly errors of a robot with the external extension axis.

[0006] In a first aspect, this application provides a robot assembly error compensation method with an external extended axis, the method comprising: S1, based on a preset position, obtain the first spatial position of the robot body and the first joint angle of the target external extension axis, and drive the target external extension axis to move a preset distance along the zero space direction of the robot body, and obtain the second spatial position of the robot body and the second joint angle of the target external extension axis, wherein the target external extension axis is any external extension axis of the robot body; S2, based on the first spatial position, the first joint angle, the second spatial position, and the second joint angle, determine the assembly error rate of the target external extension shaft; S3, obtain the initial joint angle of the target external extension axis and the target position of the robot body, and determine the target joint angle of the target external extension axis based on the target position; S4. Based on the initial joint angle, target joint angle, and assembly error rate of the target external extension shaft, determine the target position deviation; S5, the target position is corrected based on the target position deviation, and the final joint angle of the robot body is determined based on the corrected target position.

[0007] In one possible implementation, step S1 includes: When the target point on the robot body is aligned with the preset position, the first spatial position of the robot body and the first joint angle of the target's external extension axis are obtained. While keeping the robot body's posture unchanged, drive the target external extension axis to move the preset distance along the zero-space direction of the robot body, adjust the robot body's posture so that the target point is aligned with the preset position, and obtain the robot body's second spatial position and the target external extension axis's second joint angle at this time.

[0008] In one possible implementation, step S1 further includes: When the target point on the robot body is aligned with the preset position at the lower limit of the target's external extension axis, the first spatial position of the robot body and the first joint angle of the target's external extension axis are obtained. While keeping the robot body's posture unchanged, drive the target external extension axis to move along the zero-space direction of the robot body to the upper limit of the target external extension axis, adjust the robot body's posture so that the target point is aligned with the preset position, and obtain the second spatial position of the robot body and the second joint angle of the target external extension axis at this time.

[0009] In one possible implementation, after step S2, the method further includes: Based on the assembly error rate and the first joint angle of the target external extension axis obtained when the target point on the robot body is aligned with the preset position at the lower limit of the target external extension axis, an error compensation model for the target external extension axis is constructed.

[0010] In one possible implementation, the target point is the tool tip of the robot body.

[0011] In one possible implementation, step S2 includes: Based on the first spatial location and the second spatial location, determine the spatial location difference; The joint angle difference is determined based on the first joint angle and the second joint angle; Based on the spatial position difference and the joint angle difference, the assembly error rate of the target external extension shaft is determined.

[0012] In one possible implementation, step S4 includes: Based on the initial joint angle and the target joint angle of the target external extension axis, the target joint angle difference is determined; The target position deviation is determined based on the target joint angle difference and the assembly error rate of the target external extension shaft.

[0013] In one possible implementation, step S5 includes: Obtain the target position deviations corresponding to all external extended axes of the robot body, and calculate the total target position deviation; The target position is corrected based on the total target position deviation, and the inverse kinematics is solved based on the corrected target position to determine the final joint angles of the robot body.

[0014] In one possible implementation, prior to step S1, the method further includes: Verify and adjust the straightness of the target external extension axis. When the straightness of the target external extension axis meets the preset requirements, execute step S1.

[0015] On the other hand, this application also provides a computer system including a memory and a processor; the memory stores program code executable by the processor; the program code is used to perform the method as described in the first aspect or any of the implementations thereof.

[0016] The advantages of this application compared to existing technologies are as follows: Based on a preset position, a first spatial position of the robot body and a first joint angle of the target external extension axis are obtained, and the target external extension axis is driven to move a preset distance along the zero-space direction of the robot body to obtain a second spatial position of the robot body and a second joint angle of the target external extension axis; based on the first spatial position, the first joint angle, the second spatial position, and the second joint angle, the target external extension axis is calibrated to determine the assembly error rate of the target external extension axis; when positioning using an eye-to-hand vision system, the initial joint angle of the target external extension axis and the target position of the robot body are obtained, and Based on the target position, the target joint angle of the target external extension axis is determined; based on the initial joint angle of the target external extension axis, the target joint angle, and the calibrated assembly error rate, the target position deviation is determined; based on the target position deviation, the target position is corrected to eliminate the assembly error of the target external extension axis; and based on the corrected target position, the final joint angle of the robot body is determined, ensuring that even if the joint angle of the external extension axis changes, the actual position reached by the robot body after compensation with the final joint angle can accurately coincide with the target position identified by the vision system in physical space, thus improving the positioning accuracy of the robot with the external extension axis.

[0017] It is understood that the computer system provided in this application has the same beneficial effects as the robot assembly error compensation method with external extended axis described above, and will not be repeated here. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in this application, the accompanying drawings used in the description of the embodiments or prior art will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 A flowchart illustrating a robot assembly error compensation method with an external extension axis provided in an embodiment of this application; Figure 2 This is a schematic diagram illustrating an application scenario of a robot's three-axis extension, as provided in an embodiment of this application. Detailed Implementation

[0020] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of this application. However, those skilled in the art will understand that this application may be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0021] It should be understood that, when used in this application specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or a collection thereof.

[0022] It should also be understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0023] As used in this application specification and the appended claims, the term "if" may be interpreted, depending on the context, as "when," "once," "in response to determination," or "in response to detection." Similarly, the phrase "if determined" or "if detected [the described condition or event]" may be interpreted, depending on the context, as meaning "once determined," "in response to determination," "once detected [the described condition or event]," or "in response to detection [the described condition or event]."

[0024] Furthermore, in the description of this application and the appended claims, the terms "first," "second," "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0025] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0026] Depending on the specific application scenario, external extension axes can be configured along different coordinate axes of the robot. Some applications only require workspace expansion in a single direction, some require expansion in two directions simultaneously, while others require external extension axes configured in all three directions (i.e., X-axis, Y-axis, and Z-axis). It should be noted that since the external extension axes in the three directions are orthogonally decoupled and independent in space, the basic principle of error compensation is completely consistent regardless of whether it is a single-axis, dual-axis, or three-axis configuration, and all are applicable to the robot assembly error compensation method with external extension axes provided in this application.

[0027] For ease of understanding, the technical solution of this application will be described in detail below with reference to the accompanying drawings.

[0028] Figure 1 This is a flowchart illustrating a robot assembly error compensation method with an external extended axis, provided in one embodiment of this application. For ease of explanation, only the parts relevant to this embodiment are shown. The method provided in this embodiment includes the following steps: S1. Based on a preset position, obtain the first spatial position of the robot body and the first joint angle of the target external extension axis, and drive the target external extension axis to move a preset distance along the zero space direction of the robot body, and obtain the second spatial position of the robot body and the second joint angle of the target external extension axis. The target external extension axis can be any external extension axis of the robot body.

[0029] In one possible implementation, step S1 may include: When the target point on the robot body is aligned with the preset position, the first spatial position of the robot body and the first joint angle of the target's external extension axis are obtained. Keeping the robot body's posture unchanged, drive the target's external extension axis to move a preset distance along the robot body's zero-space direction, adjust the robot body's posture so that the target point is aligned with the preset position, and obtain the robot body's second spatial position and the target's external extension axis's second joint angle at this time.

[0030] Furthermore, step S1 preferably includes: When the target point on the robot body is aligned with the preset position at the lower limit of the target's external extension axis, the first spatial position of the robot body and the first joint angle of the target's external extension axis are obtained. Keeping the robot body's posture unchanged, drive the target's external extension axis to move along the robot body's zero-space direction to the upper limit of the target's external extension axis, adjust the robot body's posture to align the target point with the preset position, and obtain the robot body's second spatial position and the target's external extension axis's second joint angle at this time.

[0031] Optional, Figure 2This is a schematic diagram illustrating an application scenario of a robot's three-axis extension according to an embodiment of this application, such as... Figure 2 As shown, the robot body is equipped with an external extension axis in each of the X, Y, and Z directions, realizing omnidirectional expansion of the working range in space. In this implementation, the target external extension axis can be any one of these axes; the target point on the robot body is preferably the tip of the robot's tool end; the preset position is a preset fixed marker point on the ground; the preset distance is not less than 2 meters. If the robot's arm span is less than 2 meters, it can be moved to the physical limit position of the target external extension axis. The larger the preset distance, the higher the accuracy of the calibration results; the spatial position of the robot body can be selected as the coordinate point and pose of the robot's end effector in space, typically with 6 degrees of freedom, including 3 position values ​​and 3 attitude values.

[0032] As an example, the outer extension axis of the robot body in the x-axis direction is taken as the target outer extension axis. At the lower limit of the outer extension axis in the x-axis direction, the tip of the robot tool is precisely aligned with the fixed mark on the ground. The first spatial position p1 of the robot body and the first joint angle q1 of the outer extension axis in the x-axis direction are recorded at this time. Subsequently, keeping the robot body's posture unchanged, only the outer extension axis in the x-axis direction is driven to move, while the outer extension axes in the y-axis and z-axis directions remain stationary. The robot body moves along the zero-space direction to the upper limit of the outer extension axis in the x-axis direction. Due to assembly errors, the tip of the robot tool will inevitably deviate from the original fixed mark on the ground. At this time, the posture of the robot body needs to be adjusted so that the tip of the robot tool is precisely aligned with the fixed mark on the ground again. The second spatial position p2 of the robot body and the second joint angle q2 of the outer extension axis in the x-axis direction are recorded at this time.

[0033] S2, based on the first spatial position, the first joint angle, the second spatial position, and the second joint angle, determine the assembly error rate of the target external extension shaft.

[0034] In one possible implementation, step S2 may include: Determine the spatial position difference based on the first spatial position and the second spatial position; Determine the joint angle difference based on the first joint angle and the second joint angle; Based on the spatial position difference and joint angle difference, the assembly error rate of the target external extension shaft is determined.

[0035] As an example, the spatial position difference is determined based on the robot's first spatial position p1 and second spatial position p2. Based on the first joint angle q1 and the second joint angle q2 of the target's external extension axis, determine the joint angle difference. The ratio of the spatial position difference to the joint angle difference is used as the assembly error rate of the target external extension shaft. This represents the assembly error rate of the target external extension shaft per unit distance traveled, thus enabling the calibration of the assembly error of the target external extension shaft.

[0036] In one possible implementation, after step S2, the following may also be included: Based on the assembly error rate and the first joint angle of the target external extension axis obtained when the target point on the robot body is aligned with the preset position at the lower limit of the target external extension axis, an error compensation model for the target external extension axis is constructed.

[0037] As an example, after determining the assembly error rate of the target external extension axis, an error compensation model for the target external extension axis is established. For any joint angle q_ext of the target external extension axis, the corresponding assembly error compensation amount is Δp_comp(q_ext) = k×(q_ext - q_ref). Here, the assembly error rate k is preferably the assembly error rate obtained through the calibration process of moving the target external extension axis from the lower limit to the upper limit. q_ref represents the reference joint angle of the target external extension axis, preferably the first joint angle q1 of the target external extension axis obtained when the target point on the robot body is aligned with the preset position at the lower limit of the target external extension axis.

[0038] S3, obtain the initial joint angle of the target's external extension axis and the target position of the robot body, and determine the target joint angle of the target's external extension axis based on the target position.

[0039] As an example, during visual localization, the joint angle of the target's external extension axis at the current moment is obtained as the initial joint angle q_ext1; the target position p_vision is obtained through the robot's eye on the hand vision system, and inverse kinematics calculation is performed on the target position p_vision to obtain the target joint angle q_ext2 of the target's external extension axis.

[0040] S4. Determine the target position deviation based on the initial joint angle of the target external extension axis, the target joint angle, and the assembly error rate.

[0041] In one possible implementation, step S4 may include: The difference between the target joint angles is determined based on the initial joint angles and the target joint angles of the target's external extension axis. The target position deviation is determined based on the target joint angle difference and the assembly error rate of the target external extension shaft.

[0042] As an example, the target position deviation is the position deviation caused by the change in the position of the target's external extension shaft. It is calculated based on the initial joint angle q_ext1 of the target's external extension shaft, the target joint angle q_ext2, and the assembly error rate k, using the formula Δp' = k×(q_ext2 - q_ext1).

[0043] S5 corrects the target position based on the target position deviation, and determines the final joint angle of the robot body based on the corrected target position.

[0044] In one possible implementation, step S5 may include: Obtain the target position deviations corresponding to all external extended axes of the robot body, and calculate the total target position deviation; The target position is corrected based on the total target position deviation, and the inverse kinematics is solved based on the corrected target position to determine the final joint angles of the robot body.

[0045] As an example, when the robot body is only equipped with one external extension axis, namely the target external extension axis, the target position p_vision is corrected based on the target position deviation Δp' corresponding to the target external extension axis, and the corrected target position p_correct1 = p_vision - Δp' is obtained, thereby compensating for the assembly error of the target external extension axis; then, the inverse kinematics solution is performed on the corrected target position p_correct1 to determine the final joint angle of the robot body.

[0046] As another example, when the robot body has two or three external extension axes, the above operation is performed on each external extension axis as the target external extension axis to obtain the target position deviation Δp' corresponding to each external extension axis. Then, the sum of the target position deviations Δp' corresponding to all external extension axes is calculated to obtain the total target position deviation Δp'. 总 Based on the total target position deviation Δp' 总 The target position p_vision is corrected to obtain the corrected target position p_correct2 = p_vision - Δp' 总 This process compensates for assembly errors of all external extended axes; then, inverse kinematics is performed on the corrected target position p_correct2 to determine the final joint angles of the robot body.

[0047] Optionally, the final joint angle of the robot body is the angle of each joint in the robot body when the tip of the robot tool reaches the target position.

[0048] In one possible implementation, prior to step S1, the method may optionally include: Verify and adjust the straightness of the target's external extension axis. When the straightness of the target's external extension axis meets the preset requirements, proceed to step S1.

[0049] As an example, when the target's external extension axis is the x-axis direction, its straightness verification method includes: (1) Z-direction straightness detection: Align the horizontal laser beam of the laser level with the fixed position of the robot tool end as the reference point, keep the robot body posture unchanged, drive the external extension axis in the x-axis direction to move from the upper limit to the lower limit, and observe whether the laser spot at the reference point of the tool end is displaced. If the laser spot moves significantly, it indicates that there is a straightness deviation of the external extension axis in the Z direction in the x-axis direction, and the guide rail installation needs to be adjusted.

[0050] (2) Y-direction straightness detection: Move the external extension axis in the x-axis direction to the lower limit and mark the first reference point on the ground directly below the tip of the robot tool. Visually ensure that the tip of the tool is directly above this point. Keep the robot body posture unchanged, move the external extension axis in the x-axis direction to the upper limit and mark the second reference point. Stretch a thin line between the two reference points to form a theoretical motion trajectory reference line. Drive the external extension axis in the x-axis direction to move back and forth between the upper and lower limits. Continuously observe whether the tip of the tool is always in the center of the thin line. If there is a deviation, the installer needs to adjust the corresponding guide rail installation position. Repeat the verification until the tip of the tool is always aligned with the thin line throughout the entire stroke.

[0051] As another example, when the target's outer extension axis is the y-axis direction, its straightness verification method includes: (1) Z-direction straightness detection: Align the horizontal laser beam of the laser level with the fixed position of the robot tool end as the reference point, keep the robot body posture unchanged, drive the external extension axis in the y-axis direction to move from the upper limit to the lower limit, and observe whether the laser spot at the reference point of the tool end is displaced. If the laser spot moves significantly, it indicates that the external extension axis in the y-axis direction has a straightness deviation in the Z direction, and the guide rail installation needs to be adjusted.

[0052] (2) X-direction straightness detection: Move the external extension axis in the y-axis direction to the lower limit and mark the first reference point on the ground directly below the tip of the robot tool. Keep the robot body posture unchanged and move the external extension axis in the y-axis direction to the upper limit and mark the second reference point. Stretch a thin line between the two reference points to form a theoretical motion trajectory reference line. Drive the external extension axis in the y-axis direction to move back and forth between the upper and lower limits and observe whether the tip of the tool is always in the center of the thin line. If there is a deviation, the guide rail installation needs to be adjusted. Repeat the verification until the tip of the tool is always aligned with the thin line throughout the entire stroke.

[0053] As another example, when the target's outer extension axis is the z-axis direction, its straightness verification method includes: Since the Z-axis moves vertically, the thin line method can be used for testing: mark two reference points at the upper and lower limits of the external extension axis in the Z-axis direction, respectively, and stretch a vertical thin line between the two points (the verticality can be ensured by gravity naturally hanging down). Drive the external extension axis in the Z-axis direction to move back and forth between the upper and lower limits, and observe whether the tip of the tool is always aligned with the thin line. If there is a deviation, the guide rail installation needs to be adjusted. Repeat the verification until the tip of the tool is always aligned with the thin line throughout the entire stroke.

[0054] It should be noted that during all the above verification processes, the robot body's posture must remain strictly unchanged, and only the external extension axis of the target should be driven to move. The allowable error of the laser spot or fine line deviation can be determined according to the accuracy requirements of the actual application, and multiple reciprocating motion verifications should be performed after adjusting the guide rail to ensure the stability and repeatability of the straightness.

[0055] The straightness verification method for external extended axes provided in this implementation is low-cost and easy to implement and verify in the field.

[0056] In one possible implementation, after step S5, the method may optionally further include: verifying the assembly error compensation effect of the target external extension shaft.

[0057] As an example, the verification method for the assembly error compensation effect of the target external extended shaft includes: (1) Align the tip of the robot tool with the fixed mark on the ground precisely, and record the robot’s spatial position and the joint angle of the target’s external extension axis at this time.

[0058] (2) Keep the robot body posture unchanged, and drive the external extension axis of the target to move along the zero space direction of the robot body.

[0059] (3) During the movement, the robot assembly error compensation method with external extension axis described above is applied in real time to correct the position of the robot end, so as to ensure that the tip of the tool end is always aligned with the fixed mark point on the ground.

[0060] (4) Observe and verify the results: If the tip of the tool remains aligned with the fixed ground marker throughout the entire movement, it proves that the calibration result is accurate and the compensation method is effective. If there is a significant deviation, the calibration and compensation operation needs to be repeated.

[0061] It should be noted that each external extension axis needs to be verified separately, and the verification should be repeated at different positions of each external extension axis to ensure the consistency and stability of the compensation effect.

[0062] The technical solution provided in this application, based on a preset position, obtains the first spatial position of the robot body and the first joint angle of the target external extension axis, and drives the target external extension axis to move a preset distance along the zero-space direction of the robot body to obtain the second spatial position of the robot body and the second joint angle of the target external extension axis; based on the first spatial position, the first joint angle, the second spatial position, and the second joint angle, the target external extension axis is calibrated to determine the assembly error rate of the target external extension axis; when positioning through an eye-to-hand vision system, the initial joint angle of the target external extension axis and the target position of the robot body are obtained, and the target joint angle of the target external extension axis is determined based on the target position; based on the initial joint angle, the target joint angle, and the calibrated assembly error rate of the target external extension axis, the target position deviation is determined; based on the target position deviation, the target position is corrected to eliminate the assembly error of the target external extension axis, and the final joint angle of the robot body is determined based on the corrected target position. This ensures that when the joint angle of the external extension axis changes, the actual position reached by the robot body through the compensated final joint angle can accurately coincide with the target position identified by the vision system in physical space, thereby improving the positioning accuracy of the robot with the external extension axis.

[0063] On the other hand, this application also provides a computer system, including a memory and a processor; the memory stores program code that can be executed by the processor; the program code is used to execute any of the above-mentioned robot assembly error compensation methods with external extended axes.

[0064] For example, program code can be divided into one or more modules / units, which are stored in memory and executed by a processor to complete the present invention. One or more modules / units can be a series of computer program instruction segments capable of performing a specific function, which describe the execution process of the program code in a computer system.

[0065] The computer system can be a desktop computer, laptop, handheld computer, or cloud server, and may optionally include, but is not limited to, processors and memory. Those skilled in the art will understand that it may also include input / output devices, network access devices, buses, etc.

[0066] The processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor can be a microprocessor or any conventional processor.

[0067] Memory can be an internal storage unit of a terminal device, such as a hard drive or RAM. Memory can also be an external storage device of a terminal device, such as a plug-in hard drive, Smart MediaCard (SMC), Secure Digital (SD) card, or Flash Card. Furthermore, memory can include both internal and external storage units of a computer system. Memory is used to store program code and other programs and data required by the computer system. Memory can also be used to temporarily store data that has been output or will be output.

[0068] The computer system described above is based on the robot assembly error compensation method with external extension axis described above. Its technical function and beneficial effects will not be repeated here. The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0069] The above embodiments merely illustrate several implementation methods of this application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the inventive concept, and these all fall within the protection scope of this invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A method for compensating assembly errors in a robot with an externally extended axis, characterized in that, The method includes: S1, based on a preset position, obtain the first spatial position of the robot body and the first joint angle of the target external extension axis, and drive the target external extension axis to move a preset distance along the zero space direction of the robot body, and obtain the second spatial position of the robot body and the second joint angle of the target external extension axis, wherein the target external extension axis is any external extension axis of the robot body; S2, based on the first spatial position, the first joint angle, the second spatial position, and the second joint angle, determine the assembly error rate of the target external extension shaft; S3, obtain the initial joint angle of the target external extension axis and the target position of the robot body, and determine the target joint angle of the target external extension axis based on the target position; S4. Based on the initial joint angle, target joint angle, and assembly error rate of the target external extension shaft, determine the target position deviation; S5, the target position is corrected based on the target position deviation, and the final joint angle of the robot body is determined based on the corrected target position.

2. The method according to claim 1, characterized in that, Step S1 includes: When the target point on the robot body is aligned with the preset position, the first spatial position of the robot body and the first joint angle of the target's external extension axis are obtained. While keeping the robot body's posture unchanged, drive the target external extension axis to move the preset distance along the zero-space direction of the robot body, adjust the robot body's posture so that the target point is aligned with the preset position, and obtain the robot body's second spatial position and the target external extension axis's second joint angle at this time.

3. The method according to claim 2, characterized in that, Step S1 also includes: When the target point on the robot body is aligned with the preset position at the lower limit of the target's external extension axis, the first spatial position of the robot body and the first joint angle of the target's external extension axis are obtained. While keeping the robot body's posture unchanged, drive the target external extension axis to move along the zero-space direction of the robot body to the upper limit of the target external extension axis, adjust the robot body's posture so that the target point is aligned with the preset position, and obtain the second spatial position of the robot body and the second joint angle of the target external extension axis at this time.

4. The method according to claim 3, characterized in that, After step S2, the method further includes: Based on the assembly error rate and the first joint angle of the target external extension axis obtained when the target point on the robot body is aligned with the preset position at the lower limit of the target external extension axis, an error compensation model for the target external extension axis is constructed.

5. The method according to claim 4, characterized in that, The target point is the tip of the tool end of the robot body.

6. The method according to claim 1, characterized in that, Step S2 includes: Based on the first spatial location and the second spatial location, determine the spatial location difference; The joint angle difference is determined based on the first joint angle and the second joint angle; Based on the spatial position difference and the joint angle difference, the assembly error rate of the target external extension shaft is determined.

7. The method according to claim 1, characterized in that, Step S4 includes: Based on the initial joint angle and the target joint angle of the target external extension axis, the target joint angle difference is determined; The target position deviation is determined based on the target joint angle difference and the assembly error rate of the target external extension shaft.

8. The method according to claim 1, characterized in that, Step S5 includes: Obtain the target position deviations corresponding to all external extended axes of the robot body, and calculate the total target position deviation; The target position is corrected based on the total target position deviation, and the inverse kinematics is solved based on the corrected target position to determine the final joint angles of the robot body.

9. The method according to any one of claims 1 to 8, characterized in that, Before step S1, the method further includes: Verify and adjust the straightness of the target external extension axis. When the straightness of the target external extension axis meets the preset requirements, execute step S1.

10. A computer system, characterized in that, It includes a memory and a processor; the memory stores program code that is executed by the processor; the program code is used to execute the robot assembly error compensation method with an external extension axis as described in any one of claims 1 to 9.

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