Real-time pose adjustment method and device for articulated robot

Abstract

The invention discloses a real-time pose adjusting method and device for an articulated robot, and relates to the technical field of real-time robot control. Comprising the steps of obtaining a rotation transformation matrix of robot motion based on an established reference coordinate system of a robot motion track; according to the rotation transformation matrix, the joint angle adjustment amount of the robot is calculated; calculating a joint compensation angle according to the joint angle adjustment amount so as to obtain an actual joint position of the robot; and adjusting the pose of the robot according to the actual joint position. According to the invention, the real-time adjustment of the pose of the articulated robot is realized by designing a compensation adjustment method which has sensitivity adjustment and conforms to the characteristics of the servo motor.

Description

TECHNICAL FIELD

[0001] The present application relates to a joint robot real-time pose adjustment method and device, belonging to the field of robot real-time control. BACKGROUND

[0002] During the movement of the robot, the traditional teaching robot changes the relative position relationship between the robot and the workpiece due to assembly errors, inaccurate tool positioning and workpiece deformation, etc., resulting in deviation of the robot trajectory relative to the workpiece. In actual production, laser, vision, electric arc and other sensors are often used to correct the trajectory in real time. Most of the existing real-time offset technology solutions cannot adjust the sensitivity or set the compensation threshold limit, resulting in too fast or too slow adjustment, or causing the robot trajectory to jump, and even causing serious errors such as robot position and speed overshoot. SUMMARY

[0003] The purpose of the present application is to provide a joint robot real-time pose adjustment method and device, which realizes real-time adjustment of the pose of the joint robot by designing a compensation adjustment method with sensitivity adjustment and servo motor characteristics.

[0004] To achieve the above purpose, the present application adopts the following technical scheme.

[0005] In a first aspect, the present application provides a joint robot real-time pose adjustment method, comprising:

[0006] Based on the established reference coordinate system of the robot movement trajectory, a rotation transformation matrix of the robot movement is obtained;

[0007] According to the rotation transformation matrix, the joint angle adjustment amount of the robot is calculated;

[0008] According to the joint angle adjustment amount, the joint compensation angle is calculated, so as to obtain the actual joint position of the robot;

[0009] The pose of the robot is adjusted according to the actual joint position.

[0010] Optionally, the reference coordinate system is , wherein , and are the X-axis, Y-axis and Z-axis direction vectors of the reference coordinate system R relative to the world coordinate system W, is the tool direction vector;

[0011] The rotation transformation matrix of the reference coordinate system relative to the rectangular coordinate system is obtained from the above direction vectors is:

[0012] (1).

[0013] Optionally, the joint angles are six-axis joint angles.

[0014] Optionally, the process of calculating the joint angle adjustment amount comprises:

[0015] According to the six-axis joint angles The forward solution of the pose description matrix of the tool coordinate system relative to the world coordinate system is :

[0016] (2)

[0017] Wherein, the tool coordinate system, the world coordinate system, the flange coordinate system;

[0018] By coordinate transformation, the pose description matrix of the tool coordinate system relative to the reference coordinate system is obtained:

[0019] (3)

[0020] Wherein, .

[0021] The current pose matrix is:

[0022] (4)

[0023] Wherein, the order is ZYX, and the Euler angles are the rotation angles around the X axis, Y axis and Z axis of the reference coordinate system, respectively. From the above formula (1) - formula (4), the Euler angles and the translation amount are obtained.

[0024] According to the given adjustment amount and , the adjusted pose matrix is obtained as:

[0025] (5)

[0026] According to formula (1) and formula (5), the pose description matrix of the adjusted tool coordinate system relative to the world coordinate system is obtained as:

[0027] (6)

[0028] By inverse solution , the adjusted six-axis joint angles and the joint adjustment amount are obtained, wherein the joint adjustment amount is the difference between the adjusted joint angles and the real-time joint angles.

[0029] ​Optionally, when the joint angle adjustment amount is less than the compensation threshold, the compensation sensitivity is calculated by the joint adjustment amount to obtain the joint compensation angle;

[0030] When the joint angle adjustment amount is greater than the compensation threshold, the compensation scaling calculation is performed to obtain the adjusted joint adjustment amount, the compensation sensitivity is calculated by the adjusted joint adjustment amount to obtain the joint compensation angle, and the problem of excessive robot position adjustment amount is solved by setting the compensation threshold, and the problem of excessively fast or slow robot position adjustment speed is solved by setting the compensation sensitivity.

[0031] Optionally, the actual joint position of the robot is the sum of the interpolation joint angle and the joint compensation angle.

[0032] In a second aspect, the present application provides a real-time pose adjustment device for a joint robot, comprising:

[0033] A matrix transformation module is configured to obtain a rotation transformation matrix of the robot motion based on the established reference coordinate system of the robot motion trajectory;

[0034] A joint angle adjustment amount calculation module is configured to calculate the joint angle adjustment amount of the robot according to the rotation transformation matrix;

[0035] A joint position calculation module is configured to calculate the joint compensation angle according to the joint angle adjustment amount, so as to obtain the actual joint position of the robot;

[0036] A pose adjustment module is configured to adjust the pose of the robot according to the actual joint position.

[0037] In a third aspect, the present application provides a computer readable storage medium having a computer program / instruction stored thereon, wherein the computer program / instruction is executed by a processor to implement the steps of the real-time pose adjustment method for the joint robot according to any one of the first aspect.

[0038] In a fourth aspect, the present application provides a computer device, comprising:

[0039] A memory is configured to store a computer program / instruction;

[0040] A processor is configured to execute the computer program / instruction to implement the steps of the real-time pose adjustment method for the joint robot according to any one of the first aspect.

[0041] Compared with the prior art, the present application has the following beneficial effects:

[0042] 1. The real-time pose adjustment method for articulated robots provided by this invention establishes a reference coordinate system to obtain the rotation transformation matrix of the robot, processes the joint angles in the reference coordinate system to obtain the joint angle adjustment amount after the robot moves, and effectively solves the problem of excessive robot position adjustment by scaling the joint angle adjustment amount to within the compensation threshold. By setting the sensitivity of the joint compensation angle, the problem of excessively fast or slow robot position adjustment speed is effectively solved, thus realizing real-time pose adjustment of articulated robots.

[0043] 2. The real-time pose adjustment device for articulated robots provided by the present invention, by setting up a joint angle adjustment module and a joint calculation module, jointly realizes the pose adjustment of articulated robots, effectively improving the speed and trajectory accuracy of robot motion position adjustment;

[0044] 3. The computer-readable storage medium and computer device provided by the present invention can execute the steps of the real-time pose adjustment method for articulated robots provided by the present invention. Attached Figure Description

[0045] Figure 1 A schematic diagram of a reference coordinate system provided according to an embodiment of the present invention;

[0046] Figure 2 This is a flowchart of a method for calculating joint angle adjustment provided in an embodiment of the present invention;

[0047] Figure 3 A flowchart of a position compensation control method provided according to an embodiment of the present invention. Detailed Implementation

[0048] It should be noted that:

[0049] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the embodiments of the present invention and the specific features in the embodiments are detailed descriptions of the technical solution of the present invention, rather than limitations thereof. In the absence of conflict, the embodiments of the present invention and the technical features in the embodiments can be combined with each other.

[0050] The term "and / or" simply describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone. Additionally, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0051] Example 1

[0052] like Figure 1 As shown in the figure, this embodiment introduces a method for real-time pose adjustment of an articulated robot, including:

[0053] Based on the reference coordinate system of the established robot motion trajectory, a rotation transformation matrix of the robot motion is obtained;

[0054] According to the rotation transformation matrix, the joint angle adjustment amount of the robot is calculated;

[0055] According to the joint angle adjustment amount, a joint compensation angle is calculated, so as to obtain the actual joint position of the robot;

[0056] According to the actual joint position, the pose of the robot is adjusted.

[0057] Optionally, the reference coordinate system is an orthogonal coordinate system, and the robot sensor offset reference usually adopts two ways, one is to take the forward direction of the robot motion trajectory as the axis, and the tool direction is the reference Z axis; the other is to take the world coordinate system as the reference coordinate system . In the present application, the direction vectors of the X axis, the Y axis and the Z axis of the reference coordinate system are , and , the tool direction vector is , and the reference coordinate system is ; The rotation transformation matrix of the robot motion trajectory in the reference coordinate system relative to the rectangular coordinate system can be obtained through the direction vector of the reference coordinate system

[0058] is as follows:

[0059] (1).

[0060] Optionally, as shown in Figure 2 , the calculation process of the joint angle adjustment amount of the robot includes:

[0061] The joint angles of the joint type robot are six-axis joint angles, respectively , and the pose description matrix of the tool coordinate system relative to the world coordinate system is obtained according to the joint angles is as follows:

[0062] (2)

[0063] Among them, represents the tool coordinate system, represents the world coordinate system, represents the flange coordinate system;

[0064] The pose description matrix of the tool coordinate system relative to the reference coordinate system is obtained through coordinate transformation by

[0065] ​​​ (3)

[0066] wherein, .

[0067] The pose matrix of the current robot is:

[0068] (4)

[0069] wherein, the order is ZYX, and the Euler angles are the rotation angles around the X-axis, the Y-axis and the Z-axis of the reference coordinate system respectively, and the Euler angles and the translation can be obtained from the above formula (1) - formula (4);

[0070] According to the adjustment amount given externally, the joint angle of the robot is adjusted in real time, and the adjustment amount is and , and the adjusted pose matrix is:

[0071] (5)

[0072] Combined with formula (1) and formula (5), the pose description matrix of the adjusted tool coordinate system relative to the world coordinate system is obtained is:

[0073] (6)

[0074] Through inverse solution , the adjusted six-axis joint angle and joint adjustment amount are obtained, wherein the six-axis joint angle is , and the joint adjustment amount is the difference between the adjusted joint angle and the real-time joint angle, that is .

[0075] Optionally, as shown in Figure 3 , in order to prevent the joint motor position or motion offset speed of the six-axis joint robot from exceeding the difference during the position offset process, a position compensation method is adopted for the joint adjustment amount obtained above:

[0076] The compensation threshold of each axis is set to , when the joint angle adjustment amount of the first joint is less than the compensation threshold , in order to facilitate the sensitive adjustment of the joint of the robot, the compensation sensitivity is set. The joint compensation angle is obtained by calculating with the joint adjustment amount:

[0077] (7)

[0078] Taking servo compensation control as a position model as an example, according to the interpolation joint angle of the path planning known It can be known that the joint angle actually controlled and sent by the robot is:

[0079] (8)

[0080] When the joint angle adjustment amount of the first joint is greater than the compensation threshold , the scaling ratio of the joint angle adjustment amount of the joint is calculated:

[0081] (9)

[0082] Meanwhile, the joints of the six axes are compensated and scaled to obtain the adjusted joint adjustment amount:

[0083] (10)

[0084] In order to facilitate the sensitive adjustment of the joints of the robot, the compensation sensitivity is setThe joint compensation angle is obtained by calculating the joint adjustment amount:

[0085] (11)

[0086] Taking servo compensation control as a position model as an example, according to the interpolation joint angle of the path planning known , it can be known that the joint angle actually controlled and sent by the robot is:

[0087] (12)

[0088] According to the actual joint position of the robot obtained, the real-time adjustment of the pose of the robot can be carried out, and the problem that the robot joint position adjustment speed is too fast or too slow to cause deviation is avoided.

[0089] Embodiment 2

[0090] Based on the joint type robot real-time pose adjustment method described in embodiment 1, this embodiment introduces a joint type robot real-time pose adjustment device, which comprises:

[0091] A matrix transformation module is configured to obtain a rotation transformation matrix of the robot motion based on the reference coordinate system of the established robot motion trajectory.

[0092] A joint angle adjustment amount calculation module is configured to calculate the joint angle adjustment amount of the robot according to the rotation transformation matrix.

[0093] A joint position calculation module is configured to calculate a joint compensation angle according to the joint angle adjustment amount, so as to obtain the actual joint position of the robot.

[0094] A pose adjustment module is configured to adjust the pose of the robot according to the actual joint position.

[0095] Embodiment 3

[0096] Based on the joint robot real-time pose adjustment method described in Embodiment 1, this embodiment introduces a computer readable storage medium, which stores computer programs / instructions, and the computer programs / instructions are executed by a processor to realize the steps of the joint robot real-time pose adjustment method described in any one of Embodiments 1.

[0097] Embodiment 4

[0098] Based on the joint robot real-time pose adjustment method described in Embodiment 1, this embodiment provides a computer device, which comprises:

[0099] A memory is configured to store computer programs / instructions.

[0100] A processor is configured to execute the computer programs / instructions to realize the steps of the joint robot real-time pose adjustment method described in any one of Embodiments 1.

[0101] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system, or a computer program product. Therefore, the present application can take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROMs, optical storage devices, etc.) containing computer-usable program code.

[0102] The present application is described with reference to flowcharts and / or block diagrams of the method, device (system), and computer program product according to the embodiments of the present application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of the flows and / or blocks in the flowcharts and / or block diagrams can be implemented by computer program instructions. These computer program instructions can be provided to a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to produce a machine, so that the instructions executed by the computer or other programmable data processing devices produce a device that implements the functions specified in the flowcharts and / or block diagrams. Figure 1 An apparatus for performing the functions specified in one or more flows and / or blocks in the flowcharts and / or block diagrams. Figure 1 An apparatus for performing the functions specified in one or more flows and / or blocks in the flowcharts and / or block diagrams.

[0103] These computer program instructions can also be stored in a computer readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer readable memory produce an article of manufacture including instructions which implement the flow Figure 1 The functions of a flow or multiple flows and / or a block or multiple blocks in conjunction with the disclosed embodiments, can be implemented as hardware logic circuits, such as an integrated circuit chip (e.g., an ASIC). Figure 1

[0104] These computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flow Figure 1 The functions of a flow or multiple flows and / or a block or multiple blocks in conjunction with the disclosed embodiments, can be implemented as hardware logic circuits, such as an integrated circuit chip (e.g., an ASIC). Figure 1

[0105] The above description of the disclosed embodiments is only illustrative of the application, and not intended to limit the scope of the application. The embodiments described above are only illustrative of the application, and not intended to limit the scope of the application. Those skilled in the art can make many modifications and improvements without departing from the spirit and scope of the application, and these modifications and improvements are also within the scope of the application.​​

Claims

1. A method for real-time pose adjustment of an articulated robot, characterized in that, include: Based on the established reference coordinate system of the robot's motion trajectory, the rotation transformation matrix of the robot's motion is obtained; Calculate the joint angle adjustment of the robot based on the rotation transformation matrix; Based on the joint angle adjustment amount, the joint compensation angle is calculated to obtain the actual joint position of the robot; The robot's pose is adjusted based on the actual joint positions.

2. The real-time pose adjustment method for an articulated robot according to claim 1, characterized in that, The reference coordinate system is ,in, , and These are the X, Y, and Z direction vectors of the reference coordinate system R relative to the world coordinate system W, respectively. The tool direction vector; The rotation transformation matrix of the reference coordinate system relative to the rectangular coordinate system is obtained from the above direction vectors. for: （1）。 3. The real-time pose adjustment method for an articulated robot according to claim 1, characterized in that, The joint angle is a six-axis joint angle.

4. The real-time pose adjustment method for an articulated robot according to claim 3, characterized in that, The calculation process for the joint angle adjustment includes: Based on the six-axis joint angle The correct solution yields the pose description matrix of the tool coordinate system relative to the world coordinate system. for: （2） in, Represents the tool coordinate system. Represents the world coordinate system. Represents the flange coordinate system; Depend on After coordinate transformation, the pose description matrix of the tool coordinate system relative to the reference coordinate system is obtained as follows: （3） in, ; The current pose matrix is: （4） Among them, the regularity is ZYX, and the Euler angles are... Let be the rotation angles about the X-axis, Y-axis, and Z-axis of the reference coordinate system, respectively. The Euler angles can be obtained from equations (1) to (4) above. Translational displacement ; Based on the given adjustment amount and The adjusted pose matrix is ​​obtained. : （5） The adjusted pose description matrix of the tool coordinate system relative to the world coordinate system is obtained from equations (1) and (5). for: （6） By inverse solution The adjusted joint angle is obtained, and the joint adjustment amount is the difference between the adjusted joint angle and the real-time joint angle.

5. The real-time pose adjustment method for an articulated robot according to claim 1, characterized in that, When the joint angle adjustment amount is less than the compensation threshold, the compensation sensitivity is calculated by taking the joint adjustment amount to obtain the joint compensation angle. When the joint angle adjustment amount is greater than the compensation threshold, compensation scaling calculation is performed to obtain the adjusted joint adjustment amount. The compensation sensitivity is calculated by comparing the adjusted joint adjustment amount to obtain the joint compensation angle.

6. The real-time pose adjustment method for an articulated robot according to claim 5, characterized in that, The actual joint position of the robot is the sum of the interpolated joint angle and the joint compensation angle.

7. A real-time pose adjustment device for an articulated robot, characterized in that, include: The matrix transformation module is used to obtain the rotation transformation matrix of the robot motion based on the established reference coordinate system of the robot motion trajectory. The joint angle adjustment calculation module is used to calculate the joint angle adjustment of the robot based on the rotation transformation matrix. The joint position calculation module is used to calculate the joint compensation angle based on the joint angle adjustment amount, thereby obtaining the actual joint position of the robot; The pose adjustment module is used to adjust the robot's pose according to the actual joint positions.

8. A computer-readable storage medium having a computer program / instructions stored thereon, characterized in that, When the computer program / instruction is executed by the processor, it implements the real-time pose adjustment method for the articulated robot as described in any one of claims 1 to 6.

9. A computer device, characterized in that, include: Memory, used to store computer programs / instructions; A processor is configured to execute the computer program / instructions to implement the real-time pose adjustment method for an articulated robot as described in any one of claims 1 to 6.

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