Industrial robot control system reliability assessment method and device

Abstract

The present invention relates to the field of robotics, and more specifically to a reliability assessment method and device for an industrial robot control system. The method comprises obtaining real-time active power information of a robot in motion per unit time, obtaining force variation information of the robot in motion per unit time through the power information, establishing a robot force prediction model matrix, obtaining robot path movement node information per unit time, and establishing a real-time path time diagram of the robot. The present invention measures the displacement variable of the robot within a certain period of time and the actual power variation of the device within this period of time to obtain the force variation acting on the target object during this period of time. This method, to a certain extent, reflects the variation in the force applied to the target object due to the robot's own equipment, which may have unpredictable effects on practical applications. By determining the force applied by the robot in this manner, the reliability of the robot can be clearly analyzed.

Description

Technical Field

[0001] The present invention relates to the field of robotics technology, and in particular to a reliability evaluation method and device for an industrial robot control system. Background Art

[0002] Industrial robots are machines that perform tasks automatically. They can accept human commands, follow pre-programmed programs, or act according to principles developed using artificial intelligence. Their mission is to assist or replace human work in tasks such as manufacturing and construction, or in hazardous occupations.

[0003] At present, industrial robots have provided many conveniences to various industries. However, during the specific use process, confusion or deviation still occurs within certain time nodes. The main reason is that due to certain factors, the force applied by the robotic arm or the moving distance is too large, resulting in deviations in the processing accuracy of the workpiece. Therefore, it is necessary to evaluate and test the reliability of the robot before it is put into use. However, the current detection method ignores the reasons and detection of changes in the force applied to the force-applying end of the robot, resulting in this problem still occurring and poor actual operation reliability.

[0004] To this end, an industrial robot control system reliability evaluation method and device are proposed to solve the above-mentioned problems. Summary of the Invention

[0005] Technical problems solved

[0006] In view of the above shortcomings of the prior art, the present invention provides an industrial robot control system reliability assessment method and device, which can effectively solve the problem in the prior art that robots are difficult to assess and have poor reliability when put into use.

[0007] Technical Solution

[0008] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0009] The present invention provides a reliability assessment method for an industrial robot control system. First, it is necessary to obtain real-time active power information of the robot in motion per unit time. The power information is used to obtain information about the force change during the robot's motion per unit time. A robot force prediction model matrix is ​​then established. The operation of a common industrial robot arm is used as an example for the assessment of this method:

[0010] During the detection process, a three-dimensional coordinate system is first established in the robot's detection environment. A distance sensor or position sensor is used to determine whether the robot arm has reached the detection point. The working time between reaching the node is divided into several time points. The time it takes for the robot arm to actually reach the time point is recorded and recorded as t0, t1, t2...t x (t>0), and record the power change corresponding to the unit time node, recorded as p, p1, p2... (p>0), let p be the y-axis and t be the x-axis to form a two-dimensional coordinate system. Assuming that the p value corresponding to the period t0-t1 changes significantly, the total work done during this period is recorded as W, and the calculation formula is as follows:

[0011] W=p·t(W>0)

[0012] In the coordinate system, it is essentially the area of ​​the rectangle corresponding to the p value during the period t0-t1.

[0013] At the same time, the robot path movement node information per unit time is obtained, the robot real-time path moment diagram is established, the force prediction model matrix and the real-time path moment diagram are integrated and analyzed, the offset time node when the offset occurs is screened out, and the force intensity variable corresponding to the time point when the robot does work is obtained to judge the probability of robot work error.

[0014] In the process of determining the force intensity variable, it is first necessary to output the initial position information of the robot's force application point and the position information when it reaches the work target point according to the path movement node information in unit time, and obtain the total displacement value of the work process in unit time;

[0015] Outputting power information at a unit time node and its corresponding time node according to the robot force prediction model matrix, and when the power information at the corresponding time node fluctuates, the corresponding time node is regarded as an offset time node;

[0016] Calculate the total work value corresponding to the offset time node, and combine it with the total displacement value during the work per unit time to obtain the force intensity variable during the work per unit time.

[0017] The method for obtaining the total displacement value during the work done per unit time includes:

[0018] According to the path movement node information, the initial position information of the robot's force application point and the position information when it reaches the operation target point are output, and a three-dimensional coordinate system is established with the lateral displacement distance as the x-axis, the longitudinal displacement distance as the y-axis, and the height displacement distance as the z-axis. The distance between the initial position information and the position information when it reaches the operation target point in the three-dimensional coordinate system is calculated.

[0019] The method for determining the force intensity variable includes determining the actual work value per unit time according to the deviation power output corresponding to the offset time node;

[0020] When the output power changes, the area that overlaps with the actual total displacement value in the three-dimensional coordinate system according to the total displacement value that occurs during the work done per unit time is regarded as the offset area;

[0021] The force intensity variable of the force per unit time is obtained according to the work value per unit time and the offset area.

[0022] When the robot only makes vertical displacement in the plane direction, when the sensor on the robot arm detects that it passes through the target mark point, the corresponding up and down and left and right displacement values ​​in the coordinate system are calculated and projected into the two-dimensional plane so that the up and down direction variables are 0. Then the area enclosed by the left and right direction variables in the coordinate system is the total work done during this period, recorded as W. Assuming that the initial target point is (x0, y0) and the target point is (x1, y1), the distance of the force at this time is recorded as S.

[0023] The value of S is |y1-y0| or |x1-x0|. When the angle tilt movement occurs, the value of S is

[0024]

[0025] Similarly, when moving in three dimensions, calculate the straight-line distance between two points to obtain the distance the force acts on, and combine the relationship between the total amount of work per unit time W and S.

[0026]

[0027] in is the angle between the direction of force and the direction of displacement, and the force that can be applied per unit time, i.e. f, can be calculated.

[0028] In the step of marking the number of times the output power changes, some parameter values ​​need to be corrected. When the device is under high temperature or other external conditions, the power value will change, which makes the test result inaccurate. Therefore, the revision coefficient change range under normal conditions is set. The power change within the unit time within the normal change range is not counted, and the correction coefficient adopts the parameter value applicable to the device with similar functions to the device being tested.

[0029] The actual total displacement value calculation method includes obtaining the total displacement value by obtaining the initial position information of the force application point in the normal state per unit time and the position information when reaching the operation target point based on the work information corresponding to the revision coefficient in the normal state.

[0030] When the robot arm deviates between t0 and t1, it continues to move for a certain period of time after reaching the destination mark point, which is recorded as t3. By calculating the total displacement that occurs between t3 and t2 and combining it with the power change value that occurs during this period, the actual force can be calculated. The magnitude of the force is used as the judgment basis, combined with the revision coefficient and whether this force has an impact on the processing during the actual work process, and the corresponding records are made.

[0031] The specific calculation is as follows:

[0032]

[0033] The calculation method for determining the probability of a robot's working error includes outputting the probability of a robot's working error based on the ratio of the number of times the output power changes within a test time range to a fixed time.

[0034] For example, if three changes that are considered valid and may affect processing occur within an hour, the error rate is considered to be 3%. The cause of the failure is analyzed in the hardware, and corresponding improvements and changes are made.

[0035] A reliability assessment device for an industrial robot control system includes a node marking module and a controller. The node marking module is used to collect direction vectors in the up-down and left-right directions. The collection method is not limited to the position sensor mentioned in this example, and various devices that can measure the length of straight-line distances in a three-dimensional model, such as image processing and distance sensors, can also be used. The controller is applied to the above-mentioned industrial robot control system reliability assessment method.

[0036] Beneficial effects

[0037] Compared with the known public technologies, the technical solution provided by the present invention has the following beneficial effects:

[0038] The present invention measures the displacement variable of the robot within a certain period of time and the actual change in equipment power during this period to obtain the force variable acting on the target object during this period. To a certain extent, it reflects that there are variables in the force applied to the target object due to the robot's own equipment, which has unpredictable effects on practical applications. Through this judgment of the robot's force, the reliability of the robot can be clearly analyzed. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive effort.

[0040] Figure 1 Schematic diagram of the evaluation method steps in an embodiment of the present invention;

[0041] Figure 2 Schematic diagram of the total amount of work per unit time in an embodiment of the present invention;

[0042] Figure 3 This is a schematic diagram showing that the offset point in the embodiment of the present invention moves only in the horizontal and vertical directions;

[0043] Figure 4 Schematic diagram of the movement of the offset point in the tilt direction in an embodiment of the present invention;

[0044] Figure 5 FIG. 4 is a schematic diagram of the movement of an offset point in a three-dimensional direction in an embodiment of the present invention. DETAILED DESCRIPTION

[0045] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0046] The present invention will be further described below with reference to the embodiments.

[0047] Example: A reliability assessment method for an industrial robot control system first requires obtaining real-time active power information of the robot in motion per unit time. This power information is used to obtain information about the force variation of the robot in motion per unit time, and a robot force prediction model matrix is ​​established. The operation of a common industrial robot arm is used as an example for assessment in this method:

[0048] During the detection process, a three-dimensional coordinate system is first established in the robot's detection environment. A distance sensor or position sensor is used to determine whether the robot arm has reached the detection point. The working time between reaching the node is divided into several time points. The time it takes for the robot arm to actually reach the time point is recorded and recorded as t0, t1, t2...t x (t>0), and record the power change corresponding to the unit time node, recorded as p, p1, p2... (p>0), let p be the y-axis and t be the x-axis to form a two-dimensional coordinate system. Assuming that the p value corresponding to the period t0-t1 changes significantly, the total work done during this period is recorded as W, and the calculation formula is as follows:

[0049] W=p·t(W>0)

[0050] In the coordinate system, it is essentially the area of ​​the rectangle corresponding to the p value during the period t0-t1.

[0051] At the same time, the robot path movement node information per unit time is obtained, the robot real-time path moment diagram is established, the force prediction model matrix and the real-time path moment diagram are integrated and analyzed, the offset time node when the offset occurs is screened out, and the force intensity variable corresponding to the time point when the robot does work is obtained to judge the probability of robot work error.

[0052] In the process of determining the force intensity variable, it is first necessary to output the initial position information of the robot's force application point and the position information when it reaches the work target point according to the path movement node information in unit time, and obtain the total displacement value of the work process in unit time;

[0053] Outputting power information at a unit time node and its corresponding time node according to the robot force prediction model matrix, and when the power information at the corresponding time node fluctuates, the corresponding time node is regarded as an offset time node;

[0054] Calculate the total work value corresponding to the offset time node, and combine it with the total displacement value during the work per unit time to obtain the force intensity variable during the work per unit time.

[0055] The method for obtaining the total displacement value during the work done per unit time includes:

[0056] According to the path movement node information, the initial position information of the robot's force application point and the position information when it reaches the operation target point are output, and a three-dimensional coordinate system is established with the lateral displacement distance as the x-axis, the longitudinal displacement distance as the y-axis, and the height displacement distance as the z-axis. The distance between the initial position information and the position information when it reaches the operation target point in the three-dimensional coordinate system is calculated.

[0057] The method for determining the force intensity variable includes determining the actual work value per unit time according to the deviation power output corresponding to the offset time node;

[0058] When the output power changes, the area that overlaps with the actual total displacement value in the three-dimensional coordinate system according to the total displacement value that occurs during the work done per unit time is regarded as the offset area;

[0059] The force intensity variable of the force per unit time is obtained according to the work value per unit time and the offset area.

[0060] When the robot only makes vertical displacement in the plane direction, when the sensor on the robot arm detects that it passes through the target mark point, the corresponding up and down and left and right displacement values ​​in the coordinate system are calculated and projected into the two-dimensional plane so that the up and down direction variables are 0. Then the area enclosed by the left and right direction variables in the coordinate system is the total work done during this period, recorded as W. Assuming that the initial target point is (x0, y0) and the target point is (x1, y1), the distance of the force at this time is recorded as S.

[0061] The value of S is |y1-y0| or |x1-x0|. When the angle tilt movement occurs, the value of S is

[0062]

[0063] Similarly, when moving in three dimensions, calculate the straight-line distance between two points to obtain the distance the force acts on, and combine the relationship between the total amount of work per unit time W and S.

[0064]

[0065] in is the angle between the direction of force and the direction of displacement, and the force that can be applied per unit time, i.e. f, can be calculated.

[0066] In the step of marking the number of times the output power changes, some parameter values ​​need to be corrected. When the device is under high temperature or other external conditions, the power value will change, which makes the test result inaccurate. Therefore, the revision coefficient change range under normal conditions is set. The power change within the unit time within the normal change range is not counted, and the correction coefficient adopts the parameter value applicable to the device with similar functions to the device being tested.

[0067] The actual total displacement value calculation method includes obtaining the total displacement value by obtaining the initial position information of the force application point in the normal state per unit time and the position information when reaching the operation target point based on the work information corresponding to the revision coefficient in the normal state.

[0068] When the robot arm deviates between t0 and t1, it continues to move for a certain period of time after reaching the destination mark point, which is recorded as t3. By calculating the total displacement that occurs between t3 and t2 and combining it with the power change value that occurs during this period, the actual force can be calculated. The magnitude of the force is used as the judgment basis, combined with the revision coefficient and whether this force has an impact on the processing during the actual work process, and the corresponding records are made.

[0069] The specific calculation is as follows:

[0070]

[0071] The calculation method for determining the probability of a robot's working error includes outputting the probability of a robot's working error based on the ratio of the number of times the output power changes within a test time range to a fixed time.

[0072] For example, if three changes that are considered valid and may affect processing occur within an hour, the error rate is considered to be 3%. The cause of the failure is analyzed in the hardware, and corresponding improvements and changes are made.

[0073] A reliability assessment device for an industrial robot control system includes a node marking module and a controller. The node marking module is used to collect direction vectors in the up-down and left-right directions. The collection method is not limited to the position sensor mentioned in this example, and various devices that can measure the length of straight-line distances in a three-dimensional model, such as image processing and distance sensors, can also be used. The controller is applied to the above-mentioned industrial robot control system reliability assessment method.

[0074] In summary, this embodiment proposes a reliability assessment method for an industrial robot control system, which is applied to a test scenario and includes the following steps:

[0075] Obtain the real-time active power information of the robot in motion per unit time, obtain the force change information of the robot in motion per unit time through the power information, and establish the robot force prediction model matrix;

[0076] Obtain the robot's path movement node information per unit time and establish the robot's real-time path moment diagram;

[0077] By integrating and analyzing the force prediction model matrix and the real-time path moment diagram, the offset time node when the offset occurs is screened out, the force intensity variable corresponding to the robot's work at that time point is obtained, and the probability of robot work error is determined.

[0078] By measuring the displacement variables of the robot within a certain period of time and the actual changes in the equipment power during this period, the force variables acting on the target object during this period are obtained. To a certain extent, this reflects that there are variables in the force applied to the target object due to the robot's own equipment, which has unpredictable effects on actual applications. Through this judgment of the robot's force, the reliability of the robot can be clearly analyzed.

[0079] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements will not cause the essence of the corresponding technical solutions to deviate from the protection scope of the technical solutions of the various embodiments of the present invention.

Claims

1. The reliability assessment method of industrial robot control system is applied to the test scenario, which is characterized by: include: Obtain the real-time active power information of the robot in motion per unit time, obtain the force change information of the robot in motion per unit time through the power information, and establish the robot force prediction model matrix; Obtain the robot's path movement node information per unit time and establish the robot's real-time path moment diagram; Integrate and analyze the force prediction model matrix and the real-time path time diagram to screen out the offset time node when the offset occurs, obtain the force intensity variable when the robot performs work corresponding to the offset time node, and determine the probability of robot work error; The method for determining the force intensity variable includes: According to the path movement node information, the initial position information of the robot's force application point and the position information when it reaches the operation target point are output in unit time, and the total displacement value of the work process in unit time is obtained; Outputting power information at a unit time node and its corresponding time node according to the robot force prediction model matrix, and when the power information at the corresponding time node fluctuates, the corresponding time node is regarded as an offset time node; Calculate the total work value corresponding to the offset time node, and combine it with the total displacement value during the work per unit time to obtain the force intensity variable during the work per unit time.

2. The reliability assessment method for an industrial robot control system according to claim 1, characterized in that: The method for obtaining the total displacement value during the work done per unit time includes: According to the path movement node information, the initial position information of the robot's force application point and the position information when it reaches the operation target point are output, and a three-dimensional coordinate system is established with the lateral displacement distance as the x-axis, the longitudinal displacement distance as the y-axis, and the height displacement distance as the z-axis. The distance between the initial position information and the position information when it reaches the operation target point in the three-dimensional coordinate system is calculated.

3. The reliability evaluation method for an industrial robot control system according to claim 2, characterized in that: The method for determining the force intensity variable includes: Output the actual work value per unit time according to the corresponding deviation power in the offset time node; When the output power changes, the area that overlaps with the actual total displacement value in the three-dimensional coordinate system according to the total displacement value that occurs during the work done per unit time is regarded as the offset area; The force intensity variable of the force per unit time is obtained according to the work value per unit time and the offset area.

4. The reliability evaluation method for an industrial robot control system according to claim 3, characterized in that: The step of marking the number of times the output power changes includes: Set the revision coefficient change range under normal conditions. If the power changes within the unit time are within the normal change range, they will not be counted. The correction factor uses the parameter value applicable to equipment with similar functions to the equipment under test.

5. The reliability assessment method for an industrial robot control system according to claim 4, characterized in that: The calculation method of the actual total displacement value includes: According to the work information corresponding to the revised coefficient in the normal state, the initial position information of the force application point in the normal state in unit time and the position information when reaching the operation target point are obtained to obtain the total displacement value.

6. The reliability assessment method for an industrial robot control system according to claim 5, characterized in that: The calculation method for determining the probability of robot working error includes: The probability of robot working failure is output based on the ratio of the number of times the output power changes within the test time range to the fixed time.

7. An industrial robot control system reliability assessment device, characterized in that: include: Node marking module: The node marking module is used to collect direction vectors in the up and down, left and right directions; A controller, wherein the controller is applied to the reliability assessment method for an industrial robot control system as claimed in any one of claims 1 to 6.

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