Trajectory simplification method and device for industrial robot, computer storage medium and industrial robot operating platform

Abstract

A trajectory simplification method for an industrial robot, a trajectory simplification device (3000), a computer storage medium and an industrial robot operating platform, the method comprising: generating a complete trajectory for the industrial robot according to a teaching process of the industrial robot; and simplifying the complete trajectory to obtain a feature point set, wherein the feature point set β(j) is included in an original point set α(i), and for α(i) corresponding to β(j-1) in the original point set, j‑1 ) and α(i) corresponding to β(j) j ), the approximate error between the arbitrary point α(p) and the straight line segment with β(j-1) and β(j) as endpoints is less than or equal to the error tolerance value d, i j‑1 <p<i j , and where the approximation error is calculated according to α(i j‑1 ) and α(p) and α(i j‑1 ) and the arc length between α(p); the computer storage medium includes instructions, which execute the trajectory simplification method when running; the industrial robot operating platform includes a trajectory simplification device (3000).

Description

[Technical field]

[0001] The invention relates to a trajectory simplification method and equipment for an industrial robot, a computer storage medium and an industrial robot operating platform. [Background technology]

[0002] Robot teaching and operation is the combination of robot movement and control, the main method to achieve communication between humans and robots, and one of the most difficult and critical issues in studying and using robot systems.

[0003] The working ability of a robot is basically determined by its software system. What kind of teaching and operation the robot's software system can achieve determines the flexibility and intelligence of the robot's practical functions. For example, during the teaching process of an industrial robot for a pick-and-place task, a complete collision-free trajectory is usually generated. The generated complete trajectory is manually taught by the operator by selecting the required key points on the path on the teach pendant. This mode of operation depends on the brand of the industrial robot and the programming experience of the operator. In order to study the path and trajectory planning, the generated smooth collision-free trajectory (expressed by points with information such as position, velocity and acceleration) needs to be transmitted to the industrial robot controller that is open and provides the underlying control.

[0004] Unfortunately, the underlying control of current mainstream industrial robot controllers is not open. Therefore, if too many points are sent to and parsed in the robot controller, it will cause inconsistent velocity and acceleration of the trajectory and peak changes.

[0005] Therefore, an improved trajectory simplification scheme is desired. [Summary of the invention]

[0006] According to one aspect of the present invention, a trajectory simplification method for an industrial robot is proposed, the method comprising: generating a complete trajectory for the industrial robot during a teaching process of the industrial robot, the complete trajectory comprising an original point set α(i), i=1, 2, ..., n, where n is the number of original points in the original point set; and simplifying the complete trajectory to obtain a feature point set β(j), j=1, 2, ..., m, where m is the number of feature points in the feature point set, and the feature point set β(j) is included in the original point set α(i), m is less than or equal to n, wherein α(1)=β(1), α(n)=β(n), wherein for 1<j<m, β(j)=α(i j ), and the α(i j-1 ) and α(i) corresponding to β(j) jThe approximate error between any point α(p) between α(j-1) and the straight line segment with β(j-1) and β(j) as endpoints is less than or equal to the error tolerance value d, i j-1 <p<i j , and where the approximation error is calculated according to α(i j-1 ) and α(p) and α(i j-1 ) and the arc length between α(p).

[0007] The feature point set is obtained by simplifying the original point set, wherein the simplification method is performed by determining whether the approximate error determined by both the chord length and the arc length exceeds the error tolerance value. This trajectory simplification method has a small amount of calculation and high accuracy.

[0008] Preferably, the above-mentioned trajectory simplification method may further include: sending the simplified trajectory including the feature point set β(j) to the controller of the industrial robot.

[0009] By removing unnecessary (redundant) path points from the original point set, the complete trajectory is simplified and a feature point set is obtained. This can prevent too many points from being sent to the industrial robot controller, so that the speed and stability of the final trajectory path (such as a curved path) are significantly improved, and there is no need to open the underlying control of the industrial robot controller. The simplified path represented by the feature point set can be directly parsed and executed by the robot controller, avoiding opening the underlying control.

[0010] Preferably, in the above trajectory simplification method, the complete trajectory includes stop points for performing tasks and intermediate points with assigned motion types or commands.

[0011] Preferably, in the above trajectory simplification method, both the complete trajectory and the simplified trajectory are obstacle avoidance path trajectories.

[0012] Preferably, in the above trajectory simplification method, α(i j-1 ) and α(p) j-1 , p) is determined according to the following formula: c(i j-1 , p)=||α(p)-α(i j-1 )||.

[0013] Preferably, in the above trajectory simplification method, α(i j-1 ) and α(p) j-1 , p) is determined according to the following formula:

[0014]

[0015] Preferably, in the above trajectory simplification method, the approximate error d(ij-1 , p) is determined according to the following formula:

[0016]

[0017] Preferably, in the above trajectory simplification method, the error tolerance value d is a predetermined value, representing the maximum deviation value allowed for the simplified path.

[0018] Another embodiment of the present invention provides a trajectory simplification device for an industrial robot, the device comprising: a generating device, the generating device being configured to generate a complete trajectory for the industrial robot during a teaching process of the industrial robot, the complete trajectory comprising an original point set α(i), i=1, 2, ..., n, wherein n is the number of original points in the original point set; and a simplifying device, the simplifying device being configured to simplify the complete trajectory to obtain a feature point set β(j), j=1, 2, ..., m, wherein m is the number of feature points in the feature point set, and the feature point set β(i) is included in the original point set α(i), m is less than or equal to n, wherein α(1)=β(1), α(n)=β(m), wherein for 1<j<m, β(j)=α(i j ), and the α(i j-1 ) and α(i) corresponding to β(j) j The approximate error between any point α(p) between α(j-1) and the straight line segment with β(j-1) and β(j) as endpoints is less than or equal to the error tolerance value d, i j-1 <p<i j , and where the approximation error is calculated according to α(i j-1 ) and α(p) and α(i j-1 ) and the arc length between α(p).

[0019] The simplification device in the trajectory simplification device obtains a feature point set by simplifying the original point set. The simplification device uses the original point α(i) corresponding to the interest point α(p) and the determined feature point β(j-1). j-1 ) is determined by determining whether the approximate error determined by the chord length and arc length between the two points exceeds the error tolerance value d to determine whether the interest point is necessary. If necessary, the interest point is included in the feature point set. This trajectory simplification device has a small amount of calculation and high accuracy.

[0020] Preferably, the above-mentioned trajectory simplification device may further include: a sending device, wherein the sending device is configured to send the simplified trajectory including the feature point set β(j) to the controller of the industrial robot.

[0021] By removing unnecessary (redundant) path points from the original point set, the complete trajectory is simplified and a feature point set is obtained. This can prevent the sending device in the trajectory simplification device from sending too many points to the industrial robot controller, so that the speed and stability of the final trajectory path (such as a curved path) are significantly improved, and there is no need to open the underlying control of the industrial robot controller. The simplified path represented by the feature point set can be directly parsed and executed by the robot controller, avoiding opening the underlying control.

[0022] Preferably, in the above trajectory simplification device, the complete trajectory includes stop points for performing tasks and intermediate points with assigned motion types or commands.

[0023] Preferably, in the above-mentioned trajectory simplification device, the complete trajectory and the simplified trajectory are both obstacle avoidance path trajectories.

[0024] Preferably, in the above trajectory simplification device, α(i j-1 ) and α(p) j-1 , p) is determined according to the following formula: c(i j-1 , p)=||α(p)-α(i j-1 )||.

[0025] Preferably, in the above trajectory simplification device, α(i j-1 ) and α(p) j-1 , p) is determined according to the following formula:

[0026]

[0027] Preferably, in the above trajectory simplification device, the approximate error d(i j-1 , p) is determined according to the following formula:

[0028]

[0029] Preferably, in the above-mentioned trajectory simplification device, the error tolerance value d is a predetermined value, which represents the maximum deviation value allowed for the simplified path.

[0030] Yet another embodiment of the present invention provides a computer storage medium comprising instructions, which execute the trajectory simplification method as described above when the instructions are executed.

[0031] Yet another embodiment of the present invention provides an industrial robot operating platform, which includes the trajectory simplification device as described above.

Brief Description of the Drawings

[0032] The disclosure of the present invention will become more easily understood with reference to the accompanying drawings. It is easy for those skilled in the art to understand that these drawings are only for illustrative purposes and are not intended to limit the scope of protection of the present invention. In the drawings:

[0033] Figure 1 A trajectory simplification method for an industrial robot according to an embodiment of the present invention is shown;

[0034] Figure 2 A trajectory simplification method for an industrial robot according to another embodiment of the present invention is shown; and

[0035] Figure 3 A trajectory simplification device for an industrial robot according to an embodiment of the present invention is shown. [Specific embodiment]

[0036] The following description describes specific embodiments of the present invention to teach those skilled in the art how to make and use the best mode of the present invention. In order to teach the principles of the invention, some conventional aspects have been simplified or omitted. Those skilled in the art will appreciate that variations derived from these embodiments will fall within the scope of the present invention. Those skilled in the art will appreciate that the following features can be combined in various ways to form multiple variations of the present invention. Thus, the present invention is not limited to the following specific embodiments, but is limited only by the claims and their equivalents.

[0037] When an industrial robot is used in conjunction with path planning, an intuitive approach is to send a complete trajectory described by points (e.g., 1,000 points in total). However, most robots cannot smoothly handle a complete trajectory consisting of so many points (such as a curved path) because the interval length between adjacent points is too small and the robot must reach each point accurately, making the entire movement process unstable and causing vibrations when the TCP speed is increased. In addition, online path planning requires continuous software communication and hardware line connection so that the robot executes the planned path in each motion cycle.

[0038] One or more embodiments of the present invention address one or more of the above-mentioned problems.

[0039] refer to Figure 1 , Figure 1 A trajectory simplification method 1000 for an industrial robot according to an embodiment of the present invention is shown.

[0040] In step S110, during the teaching process of the industrial robot, a complete trajectory for the industrial robot is generated, the complete trajectory comprising an original point set α(i), i=1, 2, ..., n, where n is the number of original points in the original point set;

[0041] In step S120, the complete trajectory is simplified to obtain a feature point set β(j), j=1, 2, ..., m, where m is the number of feature points in the feature point set.

[0042] The feature point set β(j) is included in the original point set α(i), that is, m is less than or equal to n. In the feature point set β(j), its first feature point and the last feature point correspond to the first and last points in the original point set, that is, α(1) = β(1), α(n) = β(m). For other points in the feature point set, β(j) = α(i j ), 1<j<m. That is, β(j) and α(i j ). Similarly, β(j-1) corresponds to α(i j-1 ) corresponds to α(i j-1 ) and α(i j The approximate error between any point α(p) between β(j-1) and the straight line segment with β(j-1) and β(j) as endpoints is not greater than the error tolerance value d, i j-1 <p<i j , where the approximation error is calculated according to α(i j-1 ) and α(p) and α(i j-1 ) and the arc length between α(p).

[0043] In the above scheme, the starting point in the feature point set is set to be the same as the starting point in the original point. j-1 ) can represent the original point corresponding to the determined feature point β(j-1), by arranging the original point set in α(i j-1 ) are taken as interest points in turn and their approximate errors are determined to see if they exceed the error tolerance. If they do, the interest point is considered necessary and will be included in the feature point set. If the approximate error of the interest point is less than or equal to the error tolerance, the interest point is considered redundant and will not be included in the feature point set. Repeat the above process until the approximate errors of all points except the starting point and the final point have been calculated. It is worth noting that the approximate error is calculated based on the approximate error of the previously determined feature point α(i j-1 ) and the chord length between the current point of interest α(p) and α(i j-1 ) and the arc length between α(p). By using the approximation error as the basis for removing unnecessary points, this trajectory simplification method has low computational complexity and high accuracy.

[0044] refer to Figure 2 , Figure 2 FIG. 2 shows a trajectory simplification method 2000 for an industrial robot according to an embodiment of the present invention. Figure 1In comparison, in addition to steps S110 and S120, Figure 2 The trajectory simplification method 2000 further includes: step S210, sending the simplified trajectory including the feature point set β(j) to the controller of the industrial robot. In other words, the simplified trajectory (rather than the complete trajectory) is sent to the robot controller. This can avoid sending too many points to the industrial robot controller, so that the speed and stability of the final trajectory path (such as a curved path) are significantly improved, and there is no need to open the underlying control of the industrial robot controller.

[0045] In one embodiment, the industrial robot supports TCP / IP communication function, so the simplified trajectory containing the feature point set can be sent to the controller of the industrial robot via TCP / IP communication. In addition, since the simplified trajectory has been sent to the robot controller, the external hardware can be removed after the controller stores the data. The simplified path represented by the feature point set can be directly parsed and executed by the robot controller, avoiding opening the underlying control.

[0046] Combination Figure 1 and Figure 2 In one embodiment, the complete trajectory includes a stop point for performing a task and an intermediate point with an assigned motion type or command (e.g., SLIN / MoveL, etc.). In one embodiment, the complete trajectory and the simplified trajectory are both obstacle avoidance path trajectories.

[0047] In one embodiment, in the above trajectory simplification method, α(i j-1 ) and α(p) j-1 , p) is determined according to the following formula: c(i j-1 , p)=||α(p)-α(i j-1 )||.

[0048] Chord length c(i j-1 , p) represents the original point α(i) corresponding to the determined feature point β(j-1) j-1 ) and the distance value between the interest point α(p).

[0049] In one embodiment, α(i j-1 ) and α(p) j-1 , p) is determined according to the following formula:

[0050]

[0051] Arc length s(i j-1 , p) represents the original point α(i) corresponding to the determined feature point β(j-1). j-1) to the point of interest α(p), the sum of the distances between two adjacent points in the original point set.

[0052] In one embodiment, the approximation error d(i j-1 , p) is determined according to the following formula:

[0053]

[0054] According to the above formula, the original point α(i j-1 ),we can use the original point α(i j-1 ) and calculate the approximate error in sequence until the approximate error exceeds a predetermined error tolerance value d. In one embodiment, the error tolerance value d represents the maximum allowed deviation value of the simplified path.

[0055] Figure 3 FIG. 3 shows a trajectory simplification device 3000 for an industrial robot according to an embodiment of the present invention. Figure 3 The trajectory simplification device 3000 includes a generating device 310 and a simplifying device 320. Preferably, the trajectory simplification device 3000 may further include a sending device 330.

[0056] The generating device 310 is configured to generate a complete trajectory for the industrial robot during the teaching process of the industrial robot, the complete trajectory comprising a set of original points α(i), i=1, 2, ..., n, where n is the number of original points in the set of original points. In one embodiment, the complete trajectory comprises a stop point for performing a task and an intermediate point with an assigned motion type or command.

[0057] The simplification device 320 is configured to simplify the complete trajectory to obtain a feature point set β(j), j=1, 2, ..., m, where m is the number of feature points in the feature point set, and the feature point set β(j) is included in the original point set α(i), m is less than or equal to n, where α(1)=β(1), α(n)=β(m), where, for 1<j<m, β(j)=α(i j ), and the α(i j-1 ) and α(i) corresponding to β(j) j The approximate error between any point α(p) between α(j-1) and the straight line segment with β(j-1) and β(j) as endpoints is less than or equal to the error tolerance value d, i j-1 <p<i j , and where the approximation error is calculated according to α(i j-1 ) and α(p) and α(i j-1) and the arc length between α(p). In one embodiment, both the complete trajectory and the simplified trajectory are obstacle avoidance path trajectories.

[0058] The simplification device 320 simplifies the original point set to obtain the feature point set. Specifically, the simplification device 320 uses the original point α(i) corresponding to the interest point α(p) and the determined feature point β(j-1). j-1 ) exceeds the error tolerance value d to determine whether the interest point is necessary. If necessary, the interest point is included in the feature point set. With this simplification device 320, the trajectory simplification device 3000 has a small amount of calculation and high accuracy.

[0059] In one embodiment, the sending device 330 is configured to send the simplified trajectory containing the feature point set β(j) to the controller of the industrial robot. As mentioned above, the simplification device 320 has simplified the original point set generated by the generation device 310 to remove redundant path points. The sending device 330 sends the simplified path (feature point set) to the industrial robot controller, which can avoid problems such as inconsistency in velocity and acceleration of the trajectory and peak value changes caused by sending too many points. Ultimately, the speed and stability of the simplified trajectory path (such as a curved path) are significantly improved, and there is no need to open the underlying control of the industrial robot controller. The simplified path represented by the feature point set can be directly parsed and executed by the robot controller, avoiding opening the underlying control.

[0060] In one embodiment, the simplifying device 320 calculates α(i j-1 ) and α(p) j-1 , p): c(i j-1 , p)=||α(p)-α(i j-1 )||.

[0061] Chord length c(i j-1 , p) represents the original point α(i) corresponding to the determined feature point β(j-1) j-1 ) and the distance value between the interest point α(p).

[0062] In one embodiment, the simplifying device 320 calculates α(i j-1 ) and α(p) j-1 , p):

[0063]

[0064] Arc length s(i j-1 , p) represents the original point α(i) corresponding to the determined feature point β(j-1).j-1 ) to the point of interest α(p), the sum of the distances between two adjacent points in the original point set.

[0065] In one embodiment, the simplifying device 320 calculates the approximation error d(i j-1 , p):

[0066]

[0067] According to the above formula, the original point α(i j-1 ),we can use the original point α(i j-1 ) and calculate the approximate error in sequence until the approximate error exceeds a predetermined error tolerance value d. In one embodiment, the error tolerance value d represents the maximum allowed deviation value of the simplified path.

[0068] It is easy for a person skilled in the art to understand that the trajectory simplification method provided by one or more embodiments of the present invention can be implemented by a computer program. For example, when a computer storage medium (such as a USB flash drive) storing the computer program is connected to a computer, the trajectory simplification method of the embodiment of the present invention can be executed by running the computer program.

[0069] In summary, multiple embodiments of the present invention provide trajectory simplification solutions. Although only some of the specific embodiments of the present invention are described, it should be understood by those skilled in the art that the present invention can be implemented in many other forms without departing from its subject matter and scope, such as on an industrial robot operating platform. Therefore, the examples and embodiments shown are considered to be illustrative rather than restrictive, and the present invention may cover various modifications and substitutions without departing from the spirit and scope of the present invention as defined in the appended claims.

Claims

1. A trajectory simplification method for an industrial robot, the method comprising: During the teaching process of the industrial robot, a complete trajectory for the industrial robot is generated, the complete trajectory comprising a set of original points α(i), i=1, 2, ..., n, where n is the number of original points in the set of original points; as well as The complete trajectory is simplified to obtain a feature point set β(j), j=1, 2, ..., m, where m is the number of feature points in the feature point set, and the feature point set β(j) is included in the original point set α(i), m is less than or equal to n, Where α(1)=β(1), α(n)=β(m), Among them, for 1 <j<m,β(j)=α(i j ), and for the α(i j-1 ) and α(i) corresponding to β(j) j ), the approximate error between the arbitrary point α(p) and the straight line segment with β(j-1) and β(j) as endpoints is less than or equal to the error tolerance value d, i j-1 <p<i j ,as well as The approximation error is calculated according to α(i j-1 ) and α(p) and α(i j-1 ) and the arc length between α(p).

2. The trajectory simplification method according to claim 1, further comprising: The simplified trajectory including the feature point set β(j) is sent to the controller of the industrial robot.

3. The trajectory simplification method according to claim 1 or 2, wherein: The complete trajectory includes stop points for performing the task and intermediate points with assigned motion types or commands.

4. The trajectory simplification method according to claim 1 or 2, wherein: The complete trajectory and the simplified trajectory are both obstacle avoidance path trajectories.

5. The trajectory simplification method according to claim 1 or 2, wherein: α(i j-1 ) and α(p) j-1 , p) is determined according to the following formula: c(i j-1 , p)=||α(p)-α(i j-1 )||.

6. The trajectory simplification method according to claim 1 or 2, wherein: α(i j-1 ) and α(p) j-1 , p) is determined according to the following formula:

7. The trajectory simplification method according to claim 1 or 2, wherein: The approximation error d(i j-1 , p) is determined according to the following formula: Among them, c(i j-1 , p) represents α(i j-1 ) and α(p), and the length of the chord between s(i j-1 , p) represents α(i j-1 ) and α(p).

8. The trajectory simplification method according to claim 1 or 2, wherein: The error tolerance value d is a predetermined value, which represents the maximum deviation value allowed for the simplified path.

9. A trajectory simplification device for an industrial robot, the device comprising: A generating device, the generating device being configured to generate a complete trajectory for the industrial robot during a teaching process of the industrial robot, the complete trajectory comprising an original point set α(i), i=1, 2, ..., n, where n is the number of original points in the original point set; as well as A simplification device, wherein the simplification device is configured to simplify the complete trajectory to obtain a feature point set β(j), j=1, 2, ..., m, wherein m is the number of feature points in the feature point set, and the feature point set β(j) is included in the original point set α(i), and m is less than or equal to n, Where α(1)=β(1), α(n)=β(m), Among them, for 1 <j<m,β(j)=α(i j ), and for the α(i j-1 ) and α(i) corresponding to β(j) j ), the approximate error between the arbitrary point α(p) and the straight line segment with β(j-1) and β(j) as endpoints is less than or equal to the error tolerance value d, i j-1 <p<i j ,as well as The approximation error is calculated according to α(i j-1 ) and α(p) and α(i j-1 ) and the arc length between α(p).

10. The trajectory simplification device according to claim 9, further comprising: A sending device is configured to send a simplified trajectory containing the feature point set β(j) to a controller of the industrial robot.

11. The trajectory simplification device according to claim 9 or 10, wherein: The complete trajectory includes stop points for performing the task and intermediate points with assigned motion types or commands.

12. The trajectory simplification device according to claim 9 or 10, wherein: The complete trajectory and the simplified trajectory are both obstacle avoidance path trajectories.

13. The trajectory simplification device according to claim 9 or 10, wherein: α(i j-1 ) and α(p) j-1 , p) is determined according to the following formula: c(i j-1 , p)=||α(p)-α(i j-1 )||.

14. The trajectory simplification device according to claim 9 or 10, wherein: α(i j-1 ) and α(p) j-1 , p) is determined according to the following formula:

15. The trajectory simplification device according to claim 9 or 10, wherein: The approximation error d(i j-1 , p) is determined according to the following formula: Among them, c(i j-1 , p) represents α(i j-1 ) and α(p), and the length of the chord between s(i j-1 , p) represents α(i j-1 ) and α(p).

16. The trajectory simplification device according to claim 9 or 10, wherein: The error tolerance value d is a predetermined value, which represents the maximum deviation value allowed for the simplified path. 17 . A computer storage medium comprising instructions, which when executed, execute the trajectory simplification method according to any one of claims 1 to 8.

18. An industrial robot operating platform, comprising the trajectory simplification device according to any one of claims 9 to 16.

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