Robot control device

Abstract

A robot control device is provided with: a force control unit that performs force control on the basis of a detected value of an external force and a predetermined force control parameter; a contact monitoring unit configured so as to be able to monitor contact between the robot and the external environment, and perform predetermined control on the robot when the contact is monitored; and a force control parameter adjustment unit that adjusts a predetermined force control parameter by executing a plurality of times of movement of the robot according to the force control, the force control parameter adjustment unit adjusting the predetermined force control parameter while adjusting the sensitivity of the contact monitoring performed by the contact monitoring unit.

Description

Technical Field

[0001] The present disclosure relates to a robot control device. Background Art

[0002] As a teaching method for a robot, there is known a guided teaching method in which an operator teaches while directly pressing a robot arm with his hand to operate it (for example, see Patent Document 1). In the guided teaching method, the robot arm is controlled to move according to an external force applied to the robot arm by the operator.

[0003] As one of the robot control methods, force control is known. By applying force control, the robot can perform the following advanced operations: fitting operations that fit a workpiece held by a manipulator at the front end of a robot arm with an object workpiece, facing cooperation operations, and search operations (for example, refer to patent documents 2-4). In order for the robot to properly perform operations based on force control, it is necessary to properly set force control parameters for determining the relationship between the force applied to the workpiece and the behavior of the robot. Patent document 2 describes an example of a method for automatically setting a force control gain as one of the force control parameters.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2015-199174

[0007] Patent Document 2: Japanese Patent Application Publication No. 2007-237312

[0008] Patent Document 3: Japanese Patent Application Publication No. 2016-043457

[0009] Patent Document 4: Japanese Patent Application Publication No. 2019-141937 Summary of the invention

[0010] Problems to be solved by the invention

[0011] Generally, from the perspective of safety, robots that support direct teaching such as guided teaching are configured to monitor the contact between the robot and the external environment. In such robots, it is also desirable to appropriately set force control parameters in order to appropriately perform work based on force control.

[0012] A robot control device is desired that can appropriately adjust force control parameters in a robot that can monitor contact between the robot and an external environment.

[0013] Means for solving problems

[0014] One method disclosed herein is a robot control device, comprising: a force control unit, which performs force control based on a detection value of an external force and a specified force control parameter; a contact monitoring unit, which is configured to monitor the contact between the robot and an external environment and perform specified control on the robot when the contact is detected; and a force control parameter adjustment unit, which moves the robot multiple times according to the force control to thereby adjust the specified force control parameter, the force control parameter adjustment unit adjusting the specified force control parameter while adjusting the sensitivity of the contact monitoring performed by the contact monitoring unit.

[0015] These and other objects, features and advantages of the present invention will become more apparent from the detailed description of typical embodiments of the present invention as shown in the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a diagram showing the device configuration of a robot system according to one embodiment.

[0017] Figure 2 This is a diagram showing a functional block diagram of a robot control device.

[0018] Figure 3 This is a flowchart showing the overall flow of the parameter adjustment process.

[0019] Figure 4 1 is a flowchart showing the automatic adjustment process of the force control parameters.

[0020] Figure 5 This is a side view showing the posture error between the workpiece and the target object during automatic adjustment of the force control parameters.

[0021] Fig. 6A Yes means Figure 5 A top view of the posture error between the workpiece and the target object is shown.

[0022] Figure 6B It means relative to Fig. 6A A top view of the workpiece and target object with the orientation error direction different by 90 degrees.

[0023] Figure 6C It means relative to Fig. 6A A top view of the workpiece and target object with the orientation error direction different by 180 degrees.

[0024] Fig.6D It means relative to Fig. 6A Top view of the workpiece and target object with the orientation error direction different by 270 degrees.

[0025] Figure 7This is a diagram showing a state where a notification screen indicating that the force control parameter automatic setting process is being executed is displayed together with a setting screen for setting a force control parameter.

[0026] Figure 8 This is a diagram showing the robot sensitivity adjustment screen.

[0027] Fig. 9 2 is a diagram showing a state where a notification screen is displayed, where the notification screen indicates that the force control parameter automatic adjustment process is completed.

[0028] Fig.10 1 is a diagram showing a state where an indicator is displayed on the setting screen, wherein the indicator indicates the robot sensitivity after adjustment.

[0029] Fig.11 This is a diagram for explaining the display state of the sensitivity indicator of the robot sensitivity. DETAILED DESCRIPTION

[0030] Next, the embodiments of the present disclosure are described with reference to the accompanying drawings. In the referenced drawings, the same structural parts or functional parts are marked with the same figure marks. For easy understanding, the scales of these drawings are appropriately changed. In addition, the method shown in the drawings is an example for implementing the present invention, and the present invention is not limited to the method shown in the drawings.

[0031] Figure 1 1 is a diagram showing the device configuration of a robot system 100 according to an embodiment. The robot system 100 is a robot system configured to be able to perform various operations based on force control. Figure 1 As shown, the robot system 100 includes: a robot 10, a robot control device 20 for controlling the robot 10, a teaching operation panel 40 connected to the robot control device 20, and a manipulator 30. Figure 1 As shown, the robot system 100 may also include a display device 50 for displaying various information related to the execution of the action program. Figure 1 , a case where the following fitting operation is performed is shown as an example: the robot 10 fits the workpiece W1 into the fitting hole MH of the workpiece W2 on the work table 1 .

[0032] In this example, the robot 10 is a vertical multi-joint robot. In addition, a parallel link type robot or other types of robots can also be used as the robot 10. The robot 10 has a base 11 and a robot arm 12 composed of a plurality of link members. The plurality of drive axes of the robot arm 12 have: an actuator 13 including a servo motor (see Figure 2 ).

[0033] A manipulator 30 is installed at the front end of the arm of the robot 10. The manipulator 30 is driven and controlled by the robot control device 20 to hold the workpiece W1. In the fitting operation, the workpiece includes the workpiece W1 held by the manipulator 30 and the workpiece W2 on the workbench. The workpiece W1 has, for example, a cylindrical shape. The workpiece W2 is a target object to be fitted with the workpiece W1 by the action of the robot 10. The workpiece W2 has a fitting hole MH for fitting the workpiece W1. The workpiece W2 is placed on the workbench 1 in a manner that the fitting hole MH faces upward.

[0034] The robot 10 has an external force detector 15 ( Figure 2 The external force detector 15 may be composed of a force sensor mounted on the robot 10 , or may be composed of a torque sensor provided on each axis of the robot 10 . Figure 1 The example in which a force sensor 15a is arranged at the base of the robot 30 and functions as the external force detector 15 is shown. The force sensor 15a is, for example, a six-axis force sensor capable of detecting forces in the X, Y, and Z axis directions and moments around these axes. The detection value of the external force detector 15 is output to the robot control device 20.

[0035] As described above, the robot 10 is configured to be capable of executing work (such as fitting work) based on force control by including the external force detector 15 , and also capable of responding to direct teaching such as guided teaching.

[0036] Here, as a reference, a general robot having a force control function and also corresponding to direct teaching is described. Generally, in order to ensure the safety of the operator in direct teaching, the robot corresponding to direct teaching such as guided teaching is configured to be able to monitor the contact between the robot and the external environment, and, when the contact is detected, for example, stop the robot. For example, a threshold is set for the external force applied to the robot, and when the external force exceeds the threshold, it is determined that there is contact between the robot and the external environment, thereby being able to monitor the contact between the robot and the external environment. The reaction of the robot varies depending on the height of the threshold, and therefore, the setting state of the threshold is also called the sensitivity of the robot. The higher the sensitivity of the robot (that is, the lower the threshold), the more sensitive the robot is to external forces and the more it needs to stop (even if the external force is small, the robot needs to stop). The lower the sensitivity of the robot (the higher the threshold), the slower the robot's reaction to external forces (if a large external force is not applied, the robot will not stop).

[0037] In direct teaching, the threshold is usually set to a value greater than the force applied to the robot, but generally, from the viewpoint of safety, it is preferred to set the robot sensitivity higher.

[0038] In a robot capable of monitoring contact with an external environment as described above, it is considered to perform force control. In order to properly perform force control as described above, it is necessary to properly set force control parameters. Adjustment of force control parameters becomes an advanced and difficult task, so it is very beneficial for users to adopt a structure that can automatically adjust force control parameters. In the case of automatically adjusting force control parameters, the robot is generally made to try to perform force control actions and obtain adjustment values. On the other hand, as described above, it is also necessary to consider that the robot sensitivity may affect the behavior of the robot.

[0039] In view of the above, the robot control device 20 of the present embodiment is configured to be able to adjust the force control parameter while adjusting the robot sensitivity, as described in detail below.

[0040] The robot control device 20 controls the action of the robot 10 according to the action program or the instruction from the teaching operation panel 40. The robot control device 20 may have a hardware structure as a general computer, and the general computer has: a processor 21 ( Figure 2 ), memory (ROM, RAM, non-volatile memory, etc.), storage device, operating unit, input and output interface, network interface, etc.

[0041] The teaching operation panel 40 is used as an operation terminal for teaching or performing various settings of the robot 10. As the teaching operation panel 40, a teaching device composed of a tablet terminal or the like can be used. The teaching operation panel 40 can have a hardware structure as a general computer, and the general computer mentioned above has: a processor, a memory (ROM, RAM, non-volatile memory, etc.), a storage device, an operation unit, and a display unit 41 ( Figure 2 ), input and output interfaces, network interfaces, etc.

[0042] The display device 50 provides a function of displaying various information related to the execution of the action program. As the display device 50, an information processing device such as a personal computer can be used. The display device 50 can have a hardware structure as a general computer, and the above-mentioned general computer has: a processor, a memory (ROM, RAM, non-volatile memory, etc.), a storage device, an operation unit, and a display unit 51 ( Figure 2 ), input and output interfaces, network interfaces, etc.

[0043] In addition, Figure 1 , the display device 50 and the teaching operation panel 40 are provided as separate devices in the robot system 100 , but the function of the display device 50 may be integrated into the teaching operation panel 40 .

[0044] Figure 2 FIG. 2 is a functional block diagram of the robot control device 20. Figure 2As shown, the robot control device 20 includes: a motion control unit 121, a force control unit 122, a contact monitoring unit 123, a parameter automatic adjustment unit 124, a robot sensitivity adjustment unit 125, and a storage unit 126. In addition, the functional modules of the motion control unit 121, the force control unit 122, the contact monitoring unit 123, the parameter automatic adjustment unit 124, and the robot sensitivity adjustment unit 125 can also be implemented by the processor 21 executing software.

[0045] The external force detector 15 provided in the robot 10 detects the external force applied to the robot 10 and provides the detection value thereof to the force control unit 122 and the contact monitoring unit 123. The robot 10 has a sensitivity display 16 for displaying the sensitivity of the robot. The function of the sensitivity display 16 will be described in detail later. The robot 10 has an actuator 13 at each joint axis.

[0046] The teaching operation panel 40 includes a display unit 41. The display unit 41 includes, for example, a liquid crystal display. Various information related to the teaching of the robot 10 is displayed on the display unit 41, for example.

[0047] The display device 50 includes a display unit 51. The display unit 51 includes, for example, a liquid crystal display. The display unit 51 displays, for example, various information related to the execution of the operating program.

[0048] The force control unit 122 provides a function of sending a command to the motion control unit 121 based on the external force detected by the external force detector 15 and the force control parameter, thereby performing a motion based on force control. The force control parameter is stored in the storage unit 126, for example.

[0049] The motion control unit 121 controls the motion of the robot 10 according to commands from the force control unit 122, the contact monitoring unit 123, etc. The motion control unit 121 generates commands for the actuators 13 of each joint axis by kinematic calculation, thereby executing control.

[0050] The parameter automatic adjustment unit 124 provides the following function: the robot is moved according to the force control multiple times to automatically adjust the force control parameters. The force control parameters include force control gain, speed command value, force command value, etc. The force control unit 122 performs force control according to these force control parameters.

[0051] The contact monitoring unit 123 detects the contact between the robot 10 and the external environment (people, etc.), and performs prescribed control on the robot 10 when contact is detected. Here, as an example, when the magnitude of the force or torque detected by the external force detector 15 exceeds the threshold, the contact monitoring unit 123 determines that there is contact between the robot 10 and the external environment (people, etc.). The reaction of the robot 10 varies depending on the level of the threshold, so the setting state of the threshold represents the sensitivity of the contact monitoring performed by the contact monitoring unit 123. As described above, the sensitivity of the contact monitoring (the setting state of the threshold) is also referred to as the robot sensitivity. The prescribed control is to stop the robot 10, to make the robot 10 reach a sufficiently low speed, etc. In the following, the prescribed control is to stop the robot 10.

[0052] The robot sensitivity adjustment unit 125 provides a function of changing a threshold value (ie, robot sensitivity) used by the contact monitoring unit 123 to detect the presence of contact between the robot 10 and the external environment.

[0053] Lowering the threshold value corresponds to increasing the robot's sensitivity. If the robot's sensitivity is high, the robot will react sensitively to external forces and will stop with a relatively small force (external force).

[0054] Raising the threshold corresponds to reducing the robot's sensitivity. If the robot's sensitivity is low, the robot will not react well to external forces and will not stop unless a relatively large force is applied.

[0055] According to the above configuration, in both cases of performing an operation based on force control (fitting operation, etc.) and performing a guidance teaching in which the operator directly applies a force to the arm of the robot 10, etc., the robot 10 can be stopped and safety can be ensured when it is detected that the robot 10 is in contact with the external environment. In addition, during the guidance teaching, the force control unit 122 generates an action command so that the robot 10 moves in the direction of the external force detected by the external force detector 15 (the direction of the force applied to the robot 10 by the operator).

[0056] The storage unit 126 stores operation programs, force control parameters, robot sensitivity, various setting information, etc. The storage unit 126 can be composed of a nonvolatile memory, a storage device, or the like.

[0057] In the automatic adjustment of the force control parameters, the robot sensitivity may sometimes be affected. For example, when the robot sensitivity is high (i.e., when the above threshold is low), the external force is likely to exceed the limit value (the above threshold), and the robot tends to be sensitive to the external force. Therefore, the robot's movement is likely to become unstable. In addition, in this case, it is impossible to cope with force control that requires a large pressing force. In view of the above-mentioned influence of the robot sensitivity on the adjustment of the force control parameters, the automatic parameter adjustment unit 124 is configured to confirm the robot sensitivity to adjust the robot sensitivity when the parameter adjustment fails, and perform parameter adjustment again. Thereby, the force control parameters can be appropriately and automatically adjusted, and the robot sensitivity for the force control parameters can be set to the optimal state.

[0058] Figure 3 1 is a flowchart showing the overall flow of the parameter adjustment process of the present embodiment. The parameter automatic adjustment unit 124 functions as a force control parameter adjustment unit responsible for the parameter adjustment process. First, the operator teaches the necessary force control parameters (step S1). Here, for example, the operator inputs the force control parameters via a setting screen (user interface). The force control parameters input by the operator are stored in the storage unit 126.

[0059] Figure 7 The setting screen 200 for setting the force control parameters is shown in the following example. The setting screen 200 includes an input field 201 for inputting the force control parameters. The operator can teach the force control parameters by inputting values ​​into the input fields 201. The automatic parameter adjustment unit 124 may have a function of presenting such a setting screen. Such a setting screen may be displayed on the display unit 51 of the display device 50, or may be displayed on the display unit 41 of the teaching operation panel 40.

[0060] Next, the force control parameter automatic adjustment process by the parameter automatic adjustment unit 124 is executed (step S2). A bar 210 for starting the force control parameter automatic adjustment process may be provided in the setting screen 200. In this case, the operator may start the force control parameter automatic adjustment process by pressing an execution button 211. When the force control parameter automatic adjustment process is started, a notification screen 300 indicating that the force control parameter automatic adjustment process is in progress may also be displayed. In this example, the notification screen 300 includes an indicator 311 indicating the progress of the force control parameter automatic adjustment process in the form of a bar graph, and an interruption indication button 312.

[0061] Figure 4 This is a flowchart showing the automatic adjustment process of force control parameters. Figure 4 The flowchart shown, Figure 5 as well as Figure 6A-6DThe automatic adjustment process of the force control parameters performed by the automatic parameter adjustment unit 124 is described. For example, the automatic adjustment of the force control parameters is performed when the robot system is started, when the type of workpiece is changed, or when the manipulator is replaced. Here, the case of performing the fitting action of fitting the workpiece W1 held by the manipulator 30 with the fitting hole of the workpiece W2 is described as an example. The force control unit 122 and the motion control unit 121 perform control under the instruction of the automatic parameter adjustment unit 124, thereby performing the automatic parameter adjustment process.

[0062] When this process is started, first, the automatic parameter adjustment unit 124 reads the initial parameters of the force control from the storage unit 126. The force control unit 122 issues a command to the robot 10 based on the initial parameters to execute a first operation for causing the robot 10 to move so that the workpiece W1 held by the manipulator 30 is engaged with the engagement hole MH of the workpiece W2 (step S101).

[0063] Figure 5 It is a side view showing a state before the workpiece W1 gripped by the manipulator 30 is fitted into the fitting hole MH of the workpiece W2 by force control of the robot 10 based on initial parameters. Fig. 6A is its top view. Figure 5 as well as Fig. 6A , which shows the posture in which the robot 10 tilts the workpiece W1 relative to the fitting hole MH when the robot 10 is force-controlled according to the initial parameters. Specifically, the axis W1a of the workpiece W1 is tilted relative to the axis W2a of the fitting hole MH of the workpiece W2 in the -X axis direction around the Y axis ( Figure 5 as well as Fig. 6A left direction) with an inclination angle E1.

[0064] In order to properly fit the workpiece W1 into the fitting hole MH, the robot 10 needs to show a posture in which the axis W1a of the workpiece W1 is consistent with the axis W2a of the fitting hole MH. Therefore, the angle E1 represents the posture error that the robot 10 should correct when the fitting starts. The angle E1 is the change in the posture of the robot 10 required to properly fit the workpiece W1 into the fitting hole MH, that is, the posture error correction amount (E).

[0065] Here, if the rotation matrix representing the robot posture at the start of fitting is TA, and the rotation matrix representing the robot posture after fitting is TB, then inv(TB)×TA is the rotation matrix representing the posture error correction amount (E) at the start. inv is an inverse matrix. The automatic parameter adjustment unit 124 calculates the posture error correction amount (E) and stores it in the storage unit 126 (step S102).

[0066] In addition, a threshold value of the posture error correction amount is pre-set in the parameter automatic adjustment unit 124. When the absolute value of the posture error correction amount (E) calculated in step S102 is less than the threshold value, the parameter automatic adjustment unit 124 sets the posture error correction amount (E) to a predetermined value. This is to intentionally cause a posture error when there is no posture error or when the posture error is too small. The predetermined value is, for example, a threshold value. That is, when the threshold value is set to 0.5 degrees and the posture error correction amount calculated in step S102 is less than 0.5 degrees, the posture error correction amount (E) is set to 0.5 degrees.

[0067] Next, the force control unit 122 performs the second fitting operation at the same position and with the same absolute value as the posture error correction amount (E) of the robot 10 as when the first fitting operation was performed, while changing the posture error direction (step S103 ).

[0068] In step S103, the parameter automatic adjustment unit 124 performs fitting from the posture represented by the rotation matrix of TB×T(90)×inv(TB)×TA. T(90) is a matrix rotated 90 degrees around the fitting direction (around the axis W2a of the fitting hole MH) relative to the first fitting action. Figure 6B As shown, the robot 10 engages the workpiece W1 from a position where the axis W1a of the workpiece W1 is in the +Y axis direction ( Figure 6B The position is tilted at an angle E1).

[0069] Next, the force control unit 122 performs the third fitting operation at the same position and with the same absolute value as the posture error correction amount (E) of the robot 10 as in the second fitting operation, changing the posture error direction again (step S104 ).

[0070] In step S104, the parameter automatic adjustment unit 124 performs fitting from the posture represented by the rotation matrix of TB×T(180)×inv(TB)×TA. T(180) is a matrix rotated 180 degrees around the fitting direction (around the axis W2a of the fitting hole MH) relative to the first fitting action. Figure 6C As shown, the robot 10 engages the workpiece W1 from a position where the axis W1a of the workpiece W1 is in the +X axis direction ( Figure 6C to the right) is tilted at an angle E1.

[0071] Next, the force control unit 122 performs the fourth fitting operation at the same position and with the same absolute value as the posture error correction amount (E) of the robot 10 as when the third fitting operation was performed, changing the posture error direction again (step S105 ).

[0072] In step S105, the parameter automatic adjustment unit 124 performs fitting from the posture represented by the rotation matrix of TB×T(270)×inv(TB)×TA. T(270) is a matrix rotated 270 degrees around the fitting direction (around the axis W2a of the fitting hole MH) relative to the first fitting action. Fig.6D As shown, the robot 10 engages from the following position: the axis W1a of the workpiece W1 is relative to the axis W2a of the engagement hole MH of the workpiece W2 in the -Y axis direction around the X axis ( Fig.6D The upper direction) is tilted at an angle E1.

[0073] In each fitting action from the first fitting action to the fourth fitting action, the automatic parameter adjustment unit 124 records the detection value output from the external force detector 15 via the force control unit 122. After the fitting actions in the four directions (four postures) are completed, the automatic parameter adjustment unit 124 calculates the vibration amount based on the detection value of the external force detector 15 during each fitting action, and selects the direction (posture) in which the data of the detection value vibrates the most (step S106).

[0074] The vibration amount can be obtained by performing Fourier transform on the detection value of the external force detector 15 and obtaining the amplitude of a specific frequency from the result. Alternatively, the vibration amount can be obtained by obtaining the maximum value or average value of the variation of the detection value of the external force detector 15.

[0075] After selecting the direction (posture) in which the data of the detection value of the external force detector 15 vibrates the most in step S106, the parameter automatic adjustment unit 124 obtains force control parameters 1 to N adjusted only by the posture error in this direction (posture) (step S107), and changes each force control parameter to improve performance (step S108). N is the number of types of force control parameters. The types of force control parameters are force control gain, speed command value, force command value, etc. These parameters can be adjusted one by one, or the force control parameters can be adjusted for multiple parameters at the same time.

[0076] After the force control parameters are changed in step S108, the force control unit 122 moves the robot 10 according to the posture error in the direction (posture) of the most vibrating engagement action in the four directions (four postures), so that the workpiece W1 is engaged with the engagement hole MH of the workpiece W2 again (step S109).

[0077] If the force control parameters are excessively changed to improve the performance of the force control, it is easy to cause the instability of the robot 10, such as increased vibration. For example, if the force control gain is increased, the response to the generated force becomes faster, so the correction of the posture error during the mating becomes faster and the time required for the mating becomes shorter. On the other hand, if the force control gain is excessively increased, the noise is sometimes amplified so that the robot 10 oscillates. Therefore, after the automatic parameter adjustment unit 124 performs the mating action in step S109, it calculates the vibration amount based on the detection value of the external force detector 15 by the above-mentioned method to determine whether the robot 10 is oscillating (step S110). In addition, it is possible to determine whether the robot 10 is oscillating by the vibration amount being greater than the vibration amount during the last automatic parameter adjustment or exceeding a preset threshold value of the vibration amount.

[0078] In step S110, when it is determined that the robot 10 is not oscillating (step S110: No), the automatic parameter adjustment unit 124 returns to the process from step S108. That is, the automatic parameter adjustment unit 124 changes the force control parameter so that the performance of the force control parameter is further improved, and then performs the fitting operation again with the most vibrating posture error. Thereafter, in step S110, it is determined again whether the robot 10 is oscillating. The processes of step S108 and step S109 are repeated until it is determined in step S110 that the robot 10 is oscillating.

[0079] On the other hand, in step S110 , when it is determined that the robot 10 is oscillating (step S110 : Yes), the automatic parameter adjustment unit 124 returns the changed force control parameter to the previous value (step S111 ).

[0080] Thus, the force control parameter is set to a limit value that does not cause vibration in the robot 10. The automatic parameter adjustment unit 124 outputs the set force control parameter to the storage unit 126 and overwrites and stores it, and then ends the force control parameter automatic adjustment process.

[0081] In addition, the example in which the workpiece W1 is moved in a plurality of orientation error directions to automatically adjust the force control parameters is described here. However, the workpiece W1 may be moved in a plurality of position error directions and orientation error directions to automatically adjust the force control parameters.

[0082] If the force control parameter automatic adjustment process proceeds normally from step S101 to step S111 and the process ends, the automatic adjustment of the parameter automatic adjustment unit 124 is successful. On the other hand, if the force control parameter automatic adjustment process does not end normally during the process from step S101 to step S111 and the automatic adjustment value of the force control parameter is not obtained, the parameter automatic adjustment unit 124 determines that the automatic adjustment has failed, interrupts and ends the force control parameter automatic adjustment process.

[0083] Return to Figure 3 Next, the parameter automatic adjustment unit 124 confirms whether the automatic adjustment has failed (step S3).

[0084] When the automatic parameter adjustment unit 124 determines that the automatic adjustment has failed (S3: Yes), the process proceeds to step S4. In step S4, the automatic parameter adjustment unit 124 checks the robot sensitivity.

[0085] If the robot sensitivity is not the lowest (S5: No), the automatic parameter adjustment unit 124 reduces the robot sensitivity and performs the force control parameter automatic adjustment process again (step S6). When the automatic parameter adjustment unit 124 automatically adjusts the robot sensitivity, it can display the robot sensitivity adjustment unit 125. Figure 8 The sensitivity adjustment screen 310 is shown as shown. In this case, the operator can check the status of adjusting the sensitivity of the robot. Figure 8 The sensitivity adjustment screen 310 shown in the example uses the length of the bar 321 (the position of the button 322) to indicate the setting state of the robot sensitivity. Figure 7 Such a setting screen 200 is displayed together on the display screen.

[0086] When the automatic adjustment of the force control parameters is completed again, the processing from step S3 is executed.

[0087] When the robot sensitivity is the lowest (S5: Yes), the operator checks the contents of the alarm output when the force control parameter automatic adjustment process fails and ends, performs necessary adjustments, and executes the process from step S2 (step S7).

[0088] If the automatic adjustment process of the force control parameters is successful (S3: No), the process proceeds to step S8. Fig. 9 As shown, a notification screen 301 indicating that the force control parameter automatic adjustment process is completed may be displayed on the display screen. In step S8, the parameter automatic adjustment unit 124 records the adjusted robot sensitivity in, for example, the storage unit 126 (step S8).

[0089] At this time, the automatic parameter adjustment unit 124 may display an image indicating the adjusted robot sensitivity. Fig.10 The example in which the indicator 220 indicating the adjusted robot sensitivity is displayed on the setting screen 200 is shown. This allows the operator to instantly visually understand how the robot sensitivity has changed as a result of the automatic adjustment.

[0090] When the robot sensitivity set in the automatic adjustment is different from the robot sensitivity before the automatic adjustment is performed, the automatic parameter adjustment unit 124 returns the robot sensitivity to the robot sensitivity before the automatic adjustment (step S9 ).

[0091] According to the above parameter adjustment process, it is possible to automatically adjust the force control parameter to an appropriate value and set the robot sensitivity to an appropriate value. Therefore, it is possible to efficiently obtain a force control parameter that brings high performance. In addition, according to the above structure, the robot sensitivity can be set to a higher value within the range in which the automatic adjustment of the force control parameter is successful. Therefore, in the automatic adjustment of the force control parameter, the robot sensitivity setting that takes safety into consideration is achieved. That is, according to the above structure, it is possible to efficiently perform appropriate settings of the force control parameter and the robot sensitivity, and it is possible to efficiently start the robot system.

[0092] When executing the force control operation (embedding operation in the above example) as the object of parameter adjustment, the robot sensitivity recorded in step S8 is used. That is, when executing the force control operation (embedding operation in the above example) as the object of parameter adjustment in the subsequent stage, the force control unit 122 changes the robot sensitivity to the recorded robot sensitivity to perform force control. And, when the operation based on force control is completed, the robot sensitivity is returned to the original state before the operation based on force control is performed. In this way, the operator can save the trouble of manually adjusting the robot sensitivity, and the operator's workload can be reduced.

[0093] Fig.10 The setting screen 200 may be configured to allow the robot sensitivity to be adjusted by operating the button 221 of the indicator 220. For example, if the operator requires further shortening of the cycle time, the operator may set the robot sensitivity to a lower value and execute the force control parameter automatic adjustment process again.

[0094] The robot sensitivity adjustment unit 125 may be configured to display the current robot sensitivity on a sensitivity display 16 disposed on the robot 10. The sensitivity display 16 may be, for example, an LED light. Fig.11 As shown, the robot sensitivity adjustment unit 125 can be controlled so that the brightness of the LED light is brighter as the robot sensitivity is higher. The sensitivity display 16 can be arranged, for example, at a position such as the base 11 of the robot 10 that is easily visually recognized by the operator. The operator operating the robot 10 can instantly grasp the robot sensitivity through the sensitivity display 16, so displaying the robot sensitivity through the sensitivity display 16 can help improve the safety of the operation.

[0095] The robot sensitivity may be displayed by the sensitivity display 16 during the force control parameter adjustment process or may be displayed all the time during the operation of the robot 10. The sensitivity display 16 may display the sensitivity in a manner other than the sensitivity display based on brightness.

[0096] Figure 2 The functional configuration in the functional block diagram shown is an example, and there may be various modifications regarding the configuration of the functional blocks. Figure 2 The functional block diagram of FIG. 1 is an example in which a part of the functional blocks configured in the robot control device is mounted on the teaching operation panel or the display device.

[0097] Figure 2 The functional blocks of the robot control device shown may be implemented by a processor of the robot control device executing various software stored in a storage device, or may be implemented by a configuration mainly including hardware such as an ASIC (Application Specific Integrated Circuit).

[0098] Execute the parameter adjustment process in the above embodiment ( Figure 2 )、Parameter automatic adjustment processing( Figure 3 ) and other processing programs can be recorded in various computer-readable recording media (for example, semiconductor memories such as ROM, EEPROM, and flash memory, magnetic recording media, and optical disks such as CD-ROM and DVD-ROM).

[0099] As described above, according to the present embodiment, the force control parameter can be adjusted to an appropriate value, and the robot sensitivity can be adjusted appropriately.

[0100] The present disclosure has been described in detail, but the present disclosure is not limited to the above-mentioned embodiments. These embodiments can be variously added, replaced, changed, partially deleted, etc. without departing from the scope of the spirit of the present disclosure, or without departing from the scope of the spirit of the present disclosure derived from the contents recorded in the claims and their equivalents. In addition, these embodiments can also be implemented in combination. For example, in the above-mentioned embodiments, the order of each action and the order of each processing are shown as an example, which is not limited to this. In addition, the same is true for the case where numerical values ​​or mathematical formulas are used in the description of the above-mentioned embodiments.

[0101] The following supplementary notes are further described with respect to the above-mentioned embodiment and modified examples.

[0102] (Note 1)

[0103] A robot control device, comprising:

[0104] a force control unit that performs force control according to a detected value of the external force and a specified force control parameter;

[0105] a contact monitoring unit configured to monitor contact between the robot and an external environment and to perform predetermined control on the robot when the contact is detected; and

[0106] a force control parameter adjustment unit that moves the robot according to the force control a plurality of times to adjust the prescribed force control parameter,

[0107] The force control parameter adjustment unit adjusts the predetermined force control parameter while adjusting the sensitivity of contact monitoring performed by the contact monitoring unit.

[0108] (Note 2)

[0109] The robot control device according to Supplement 1, wherein:

[0110] The force control parameter adjustment unit reduces the sensitivity of the contact monitoring when the adjustment of the force control parameter fails, and repeatedly adjusts the force control parameter until the adjustment of the force control parameter succeeds.

[0111] (Note 3)

[0112] A robot control device according to Supplement 1 or 2, wherein:

[0113] The force control parameter adjustment unit records the sensitivity of the contact monitoring when the adjustment of the force control parameter is successful.

[0114] (Note 4)

[0115] The robot control device according to any one of Supplementary Notes 1 to 3, wherein:

[0116] After the force control parameter is successfully adjusted, the force control parameter adjustment unit returns the sensitivity of the contact monitoring to an original state before the force control parameter is adjusted.

[0117] (Note 5)

[0118] The robot control device according to Supplement 3, wherein:

[0119] The force control unit changes the sensitivity of the contact monitoring to the recorded sensitivity of the contact monitoring when executing the force control.

[0120] (Note 6)

[0121] The robot control device according to Supplementary Note 5, wherein:

[0122] After executing the force control, the force control unit returns the sensitivity of the robot to a state before executing the force control.

[0123] (Note 7)

[0124] The robot control device according to any one of Supplementary Notes 1 to 6, wherein:

[0125] The force control parameter adjustment unit displays a user interface screen, and the user interface screen is used to display the sensitivity of the contact monitoring when the adjustment of the force control parameter is successful.

[0126] (Note 8)

[0127] The robot control device according to Supplement 7, wherein:

[0128] The user interface screen is configured to accept the following operations and instructions:

[0129] User operation to adjust the sensitivity of the contact monitoring; and

[0130] The force control parameter adjustment unit is instructed to adjust the force control parameter again using the sensitivity of the contact monitoring adjusted by the user operation.

[0131] (Note 9)

[0132] A robot control device according to any one of Supplementary Notes 1 to 8, wherein:

[0133] The force control parameter adjustment unit sends a signal for the following function: adjusting the brightness of a sensitivity display provided on the robot according to the sensitivity of the contact monitoring currently applied to the robot.

[0134] Explanation of symbols

[0135] 10. Robot

[0136] 11 Base

[0137] 12 Robotic Arm

[0138] 13 Actuator

[0139] 15 External force detector

[0140] 16 Sensitivity display

[0141] 20 Robot control device

[0142] 21 Processor

[0143] 30 Robot

[0144] 40 Teaching operation panel

[0145] 41 Display

[0146] 50 Display device

[0147] 51 Display

[0148] 100 Robotic Systems

[0149] 121 Motion Control Unit

[0150] 122 Force Control Department

[0151] 123 Contact Monitoring Department

[0152] 124 Parameter automatic adjustment unit

[0153] 200 Setting screen

[0154] 220 Indicator

[0155] 300, 301 notification screen

[0156] 310 sensitivity adjustment screen.

Claims

1. A robot control device, characterized in that: The robot control device has: a force control unit that performs force control according to a detected value of the external force and a specified force control parameter; a contact monitoring unit configured to monitor contact between the robot and an external environment and to perform predetermined control on the robot when the contact is detected; and a force control parameter adjustment unit that moves the robot according to the force control a plurality of times to adjust the prescribed force control parameter, The force control parameter adjustment unit adjusts the predetermined force control parameter while adjusting the sensitivity of contact monitoring performed by the contact monitoring unit.

2. The robot control device according to claim 1, characterized in that: The force control parameter adjustment unit reduces the sensitivity of the contact monitoring when the adjustment of the force control parameter fails, and repeatedly adjusts the force control parameter until the adjustment of the force control parameter succeeds.

3. The robot control device according to claim 1 or 2, characterized in that: The force control parameter adjustment unit records the sensitivity of the contact monitoring when the adjustment of the force control parameter is successful.

4. The robot control device according to any one of claims 1 to 3, characterized in that: After the force control parameter is successfully adjusted, the force control parameter adjustment unit returns the sensitivity of the contact monitoring to an original state before the force control parameter is adjusted.

5. The robot control device according to claim 3, characterized in that: The force control unit changes the sensitivity of the contact monitoring to the recorded sensitivity of the contact monitoring when executing the force control.

6. The robot control device according to claim 5, characterized in that: After executing the force control, the force control unit returns the sensitivity of the robot to a state before executing the force control.

7. The robot control device according to any one of claims 1 to 6, characterized in that: The force control parameter adjustment unit displays a user interface screen, and the user interface screen is used to display the sensitivity of the contact monitoring when the adjustment of the force control parameter is successful.

8. The robot control device according to claim 7, characterized in that: The user interface screen is configured to accept the following operations and instructions: User operation to adjust the sensitivity of the contact monitoring; and The force control parameter adjustment unit is instructed to adjust the force control parameter again using the sensitivity of the contact monitoring adjusted by the user operation.

9. The robot control device according to any one of claims 1 to 8, characterized in that: The force control parameter adjustment unit sends a signal for the following function: adjusting the brightness of a sensitivity display provided on the robot according to the sensitivity of the contact monitoring currently applied to the robot.

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