Teaching device, control device, and mechanical system

Abstract

This teaching device comprises a teaching unit that, using a force detector, binds a force parameter of a force control command for a machine, and a movement trajectory of the machine which executes force control, and that simultaneously teaches the force parameter and the movement trajectory.

Description

[Technical Field]

[0001] The present invention relates to a machine teaching technique, and more particularly to a teaching device, a control device, and a machine system that facilitate the teaching of force control. [Background technology]

[0002] To intuitively create operation programs for machines, including robots and machine tools, icon-based programming has been proposed, in which operation programs are created by arranging icons representing control commands for the machine. Meanwhile, a widely known technology performs force control based on the force acting on the machine's control point, which is determined from information detected by force detectors, including force sensors and torque sensors. Teaching force control commands requires teaching many parameters, such as the machine's motion trajectory, the machine's approach speed to the workpiece, the magnitude and direction of the force applied to the workpiece, the machine's movement speed, and the machine's attitude.

[0003] Well-known methods for teaching the motion trajectory of a machine include playback teaching, in which the motion trajectory of the machine is recorded and played back while actually operating the machine using a teaching control panel or teach pendant, online teaching such as direct teaching, in which the instructor records and teaches the motion trajectory of the machine while directly operating the controlled part of the machine or a handle attached near the controlled part, and offline teaching, in which the motion trajectory of the machine is recorded and taught while operating a model of the machine in a virtual space generated by a computer.

[0004] A widely known method for teaching force control involves specifying various parameters, such as the approach speed to a workpiece (including a workpiece or tool), the magnitude and direction of the force applied to the workpiece, and the machine's movement speed. However, the following problems arise when teaching force control commands: (1) Because the number of teaching points that make up the machine's motion trajectory increases during force control, adjusting the machine's position and posture at each teaching point becomes tedious. Furthermore, (2) because force control commands require the teaching of many parameters, such as the machine's approach speed to the workpiece, the magnitude and direction of the force applied to the workpiece, the machine's movement speed, and the machine's posture, teaching can be difficult and time-consuming if the instructor has little knowledge of the parameters (especially if they are a beginner).

[0005] Furthermore, (3) the parameters of the force control command cannot be taught intuitively, and knowledge of coordinate systems, etc. is required when setting the magnitude and direction of the force to be applied to the workpiece, making it difficult to use. Additionally, (4) when adjusting the parameters of the taught force control command, the adjusted parameters are applied to all taught points, so the magnitude and direction of the force cannot be flexibly adjusted for each taught point. The following documents, for example, are known as background art related to this application.

[0006] Patent Document 1 describes a method of teaching a machine's motion trajectory by direct teaching, interrupting playback by pressing a teaching switch during playback, and re-teaching the trajectory after the interruption.

[0007] Patent Document 2 describes that a force-controlled pressing device installed at the tip of a robot is equipped with a movement mechanism that sets the pressing direction of the force-controlled pressing device. It also describes that the force-controlled pressing device is equipped with a force sensor that measures the force acting between the tool and the workpiece.

[0008] Patent Document 3 describes a teaching method that directly teaches a robot based on the output signal of a force sensor, in which the hand is moved according to the operating force applied by the operator to the force sensor only while the teaching switch is on, thereby improving positioning accuracy while providing a good operating feel. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-049731 [Patent Document 2] Japanese Patent Application Laid-Open No. 2018-118340 [Patent Document 3] Japanese Patent Application Publication No. 59-157715 Summary of the Invention [Problem to be solved by the invention]

[0010] In view of the problems of the prior art, an object of the present invention is to provide a technique that makes it easy to teach force control. [Means for solving the problem]

[0011] According to one aspect of the present disclosure, a force parameter of a force control command for a machine is linked to a motion trajectory of the machine to be subjected to force control using a force detector. Teaching Equipped with a teaching unit that shows The teaching unit teaches parameters other than the force parameters and the motion trajectory, and the parameters include at least one of an approach speed of the machine to the work object and a movement speed of the machine. A teaching device is provided. Another aspect of the present disclosure is a method for linking a force parameter of a force control command to a machine with a motion trajectory of the machine that performs force control using a force detector. Teaching a program generating unit that generates an operation program for the machine based on the force control command; and a control unit that operates the machine in accordance with the operation program and controls the force of the machine. The teaching unit teaches parameters other than the force parameters and the motion trajectory, and the parameters include at least one of an approach speed of the machine to the work object and a movement speed of the machine. A control device is provided. Another aspect of the present disclosure relates to a machine equipped with a force detector, and a method for linking a force parameter of a force control command for the machine using the force detector with a motion trajectory of the machine that performs force control. Teachinga program generating unit that generates an operation program for the machine based on the force control command; and a control unit that operates the machine in accordance with the operation program and controls the force of the machine. The teaching unit teaches parameters other than the force parameters and the motion trajectory, and the parameters include at least one of an approach speed of the machine to the work object and a movement speed of the machine. Provide a mechanical system. [Effects of the Invention]

[0012] According to one aspect of the present disclosure, a force detector is used to associate and simultaneously teach the force parameters of a force control command with the motion trajectory of a machine that performs force control, thereby enabling easy and efficient teaching of force parameters, facilitating teaching of force control, and shortening the system startup time compared to conventional systems. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a configuration diagram of a mechanical system according to a first embodiment. [Figure 2] FIG. 2 is a functional block diagram of the mechanical system of the first embodiment. [Figure 3] FIG. 10 is an explanatory diagram illustrating an example of a teaching method for force control. [Figure 4] 10 shows an example of a force control program creation screen. [Figure 5] 10 shows an example of a force control program creation screen. [Figure 6] 10 shows an example of a force control program creation screen. [Figure 7] 10 is a flowchart showing an example of a method for teaching force control. [Figure 8] FIG. 10 is a functional block diagram of a mechanical system according to a second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In each drawing, the same or similar components are assigned the same or similar reference numerals. Furthermore, the embodiments described below do not limit the technical scope of the invention described in the claims and the meaning of terms. In this specification, the term "force parameters" includes the magnitude and direction of a force applied to a work object, and the term "motion trajectory" includes at least the position of a teaching point. Furthermore, in this specification, the term "screen" means all or a partial area of ​​the screen of one or more display devices, and the term "window" means a partial area of ​​the screen.

[0015] The following describes a mechanical system 1 according to the first embodiment. Fig. 1 is a configuration diagram of the mechanical system 1 according to the first embodiment. The mechanical system 1 includes a machine 2, a control device 3 that controls the operation of the machine 2, and a teaching device 4 that teaches the machine 2 how to operate.

[0016] Machine 2 is configured as an articulated robot, but is not limited to this, and in other embodiments, it may be configured as other industrial robots such as a single-joint robot, a parallel link robot, or a dual-arm robot. In another embodiment, machine 2 may not be an industrial robot, but may be configured as other types of robots such as a humanoid. Alternatively, in yet another embodiment, machine 2 may not be a robot, but may be configured as other industrial machines such as machine tools, construction machines, or agricultural machines, or other types of machines such as vehicles, aircraft, or rockets.

[0017] The machine 2 includes one or more links 10-16 interconnected to one another. The links 11-16 are configured as rotary links that rotate about axes J1-J6, respectively, but are not limited thereto. In other embodiments, the links may be configured as linear links that move linearly along the axes J1-J6. The zeroth link 10 is, for example, a base fixed in a predetermined position, and the first link 11 is, for example, a rotating body supported rotatably relative to the zeroth link 10 about a first axis J1. The second link 12 is, for example, an upper arm supported rotatably relative to the first link 11 about a second axis J2 perpendicular to the first axis J1, and the third link 13 is, for example, a forearm supported rotatably relative to the second link 12 about a third axis J3 parallel to the second axis J2.

[0018] The fourth link 14 to the sixth link 16 form a three-axis wrist attached to the third link 13. The fourth link 14 is a first wrist element supported rotatably relative to the third link 13, for example, about a fourth axis J4 perpendicular to the third axis J3, the fifth link 15 is a second wrist element supported rotatably relative to the fourth link 14, for example, about a fifth axis J5 perpendicular to the fourth axis J4, and the sixth link 16 is a third wrist element supported rotatably relative to the fifth link 15, for example, about a sixth axis J6 perpendicular to the fifth axis J5.

[0019] Although not required, the machine 2 may be equipped with a visual sensor 17 that acquires images of the workspace in which the workpiece W, including the workpiece or tool, is located. The visual sensor 17 is configured as a two-dimensional camera, but is not limited to this and may be configured as a three-dimensional camera in other embodiments. The control device 3 or the teaching device 4 may obtain parameters such as the machining results of the workpiece W and the position and attitude of the machine 2 from the detection information of the visual sensor 17.

[0020] The machine 2 further includes a force detector 18 attached near the control point P of the machine 2 (between the wrist and the tool 19 in this example). The force detector 18 is configured as a force sensor that detects forces in three axial directions and moments about three axes, but is not limited to this. In other embodiments, the force detector 18 may be configured as a force sensor that detects forces on at least one axis. Alternatively, in another embodiment, the force detector 18 may not be configured as a force sensor attached to the wrist, but may be configured as one or more torque sensors provided at the connection points of the first link 11 to the sixth link 16. The torque sensors detect torques acting on the first link 11 to the sixth link 16. The control device 3 or the teaching device 4 determines the magnitude and direction of the force to be applied to the workpiece W (i.e., force parameters) from the detection information of the force detector 18.

[0021] Machine 2 further includes tool 19 attached to the tip of machine 2. In this embodiment, tool 19 is configured as a deburring tool that deburrs workpiece W, but is not limited to this. In other embodiments, tool 19 may be configured as other types of tool, such as a hand tool, welding tool, screw tightening tool, cutting tool, grinding tool, or hemming tool. In this embodiment, machine 2 performs a deburring operation by pressing the deburring tool along the processing line L of workpiece W, but is not limited to this. In other embodiments, machine 2 may perform a deburring operation in which workpiece W held by a hand tool is pressed against a tool such as a deburring tool or grinding tool to remove burrs, a fitting operation in which a convex workpiece held by a hand tool is fitted into a concave workpiece, a surface matching operation in which a first workpiece held by a hand tool is fitted with a second workpiece, a phase matching operation in which a first gear held by a hand tool is fitted with a second gear, or a screw tightening operation in which a male thread held by a hand tool is fastened to a female thread.

[0022] The machine 2 is equipped with one or more actuators 20 that drive the links 11 to 16 and one or more motion detectors 21 that detect the motion of the actuators 20 (see FIG. 2). The actuators 20 are provided near the joints of the links 11 to 16. The actuators 20 are configured as electric actuators including electric motors, reducers, etc., but are not limited to this and may be configured as other types of actuators such as hydraulic or pneumatic types in other embodiments. The motion detectors 21 are configured as encoders, but are not limited to this and may be configured as other types of motion detectors such as resolvers or Hall sensors in other embodiments. The control device 3 or the teaching device 4 may obtain parameters such as the position and posture of the machine 2, the moving speed of the machine 2, and the approach speed to the workpiece W from the detection information of the motion detectors 21.

[0023] The control device 3 includes a programmable logic controller (PLC) or the like, but is not limited to this, and in other embodiments, may be configured as another type of computer including a processor, memory, input / output interface, etc., connected to each other by a bus. The control device 3 further includes a drive circuit for driving the actuator 20, but is not limited to this, and in other embodiments, the machine 2 may include a drive circuit for driving the actuator 20. The control device 3 drives the actuator 20 to control the machine 2. The control device 3 receives detection information from the motion detector 21 and the force detector 18, respectively, and the teaching device 4 receives detection information from the motion detector 21 and the force detector 18 from the control device 3, but is not limited to this, and in other embodiments, the teaching device 4 may receive detection information directly from the motion detector 21 and the force detector 18, respectively.

[0024] The control device 3 can set various coordinate systems, such as a world coordinate system, a machine coordinate system, a flange coordinate system, a tool coordinate system, a camera coordinate system, and a user coordinate system. These coordinate systems are, for example, Cartesian coordinate systems. For ease of explanation, it is assumed that the control device 3 sets a machine coordinate system C1, a tool coordinate system C2, and a user coordinate system C3. The machine coordinate system C1 is fixed to a reference position of the machine 2, for example, the base, the tool coordinate system C2 is fixed to a reference position of the tool 19, for example, the tool center point (TCP), and the user coordinate system C3 is fixed to an arbitrary position, for example, the reference position of the workpiece W.

[0025] The control device 3 sets the control point P of the machine 2 to the origin of the tool coordinate system C2 (i.e., the tool center point: TCP). Therefore, the position and orientation of the part to be controlled of the machine 2 (the tool in this example) (hereinafter referred to as the position and orientation of the machine 2) are expressed as the position and orientation of the tool coordinate system C2 in the machine coordinate system C1. In other embodiments, the position and orientation of the machine 2 may be expressed as the position and orientation of the flange coordinate system in the machine coordinate system C1, or as the position and orientation of the tool coordinate system C2 or flange coordinate system in the user coordinate system C3. The control device 3 controls the operation of the machine 2 in accordance with an operation program created by the teaching device 4.

[0026] The operation program includes various control commands such as a movement command to move the control point P of the machine 2 to a teaching point that constitutes the operation trajectory T of the machine 2, a force control command to control the force applied to the work object W, an application command to make the machine 2 execute a predetermined operation pattern (palletizing, depalletizing, etc.), a conditional branch command to branch the control command under a predetermined condition, and a loop command to loop a predetermined control command under a predetermined condition.

[0027] The teaching device 4 is configured as a portable teach pendant connected to the control device 3 via a wired or wireless connection, but is not limited to this, and in other embodiments, it may be configured as another type of device, such as a teaching operation panel directly attached to the control device 3, a tablet, or another computer device including a personal computer. The teaching device 4 includes a processor, memory, input / output interface, user interface, etc., which are mutually connected by a bus. The user interface is configured as a display device such as a touch panel or display, and an input device such as a keyboard, buttons, switches, etc. The teaching device 4 is connected to the control device 3 via a wired or wireless connection.

[0028] The teaching device 4 is equipped with programming software that creates an operation program for the machine 2. The programming software is configured as icon-based programming software that creates an operation program by arranging icons that represent control commands for the machine 2, but is not limited to this, and in other embodiments, it may be configured as text-based programming software that creates an operation program by arranging text that represents control commands for the machine 2. The teaching device 4 sends the created operation program to the control device 3.

[0029] In the machine system 1 configured as described above, the control device 3 operates the machine 2 according to an operation program to perform force control of the machine 2, and the machine 2 performs, for example, deburring of a workpiece W using a tool 19. When teaching a force control command, it is necessary to teach many parameters, such as the movement trajectory T of the machine 2, the approach speed of the machine 2 to the workpiece W, the magnitude and direction of the force applied to the workpiece W, the movement speed of the machine 2, and the attitude of the machine 2.

[0030] Methods for teaching the motion trajectory T of the machine 2 include online teaching such as playback teaching, in which the motion trajectory of the machine 2 is recorded and played back while actually moving the machine 2 using a teaching device 4 such as a teaching operation panel or teach pendant, direct teaching, in which the instructor records and teaches the motion trajectory of the machine 2 while directly moving the controlled part of the machine 2 or a handle attached near the controlled part, or offline teaching, in which the motion trajectory of the machine 2 is recorded and taught while moving a model of the machine 2 in a virtual space generated by the teaching device 4.

[0031] One method of teaching force control involves specifying various parameters, such as the approach speed to the workpiece W, the magnitude and direction of the force to be applied to the workpiece W, and the machine's movement speed, but this raises the following problems: (1) During force control, the number of teaching points that make up the machine's trajectory T becomes large, making it cumbersome to adjust the position and posture of the machine 2 at each teaching point. Also, (2) because force control commands require the teaching of many parameters, such as the machine's approach speed to the workpiece, the magnitude and direction of the force to be applied to the workpiece, the machine's movement speed, and the machine's posture, if the instructor has little knowledge of the parameters (especially if they are a beginner), teaching can be difficult and time-consuming.

[0032] Furthermore, (3) the parameters of the force control command cannot be taught intuitively, and knowledge of coordinate systems, etc. is required when setting the magnitude and direction of the force to be applied to the work object, making it difficult to use. Additionally, (4) when adjusting the parameters of the taught force control command, the adjusted parameters are applied to all teaching points, so the magnitude and direction of the force cannot be flexibly adjusted for each teaching point.

[0033] Therefore, in the first embodiment, the force parameters of the force control command for the machine 2 and the motion trajectory T of the machine 2 that performs the force control are linked and simultaneously taught using the force detector 18. This teaching is performed by recording the force parameters linked to the motion trajectory T by direct teaching or playback teaching. It is also advisable to teach other parameters other than the force parameters and the motion trajectory (such as the approach speed of the machine 2 to the workpiece W, the movement speed of the machine 2, and the attitude of the machine 2) simultaneously.

[0034] The functional blocks of the mechanical system 1 of the first embodiment will be described below. Fig. 2 is a functional block diagram of the mechanical system 1 of the first embodiment. The teaching device 4 includes a user interface (UI) unit 40, a storage unit 45, and a communication control unit 48. The UI unit 40 is configured with hardware such as a touch panel, a display, a keyboard, buttons, and switches. The storage unit 45 is configured with memory such as RAM (random access memory), ROM (read only memory), and SSD (solid state drive). The communication control unit 48 is configured with hardware such as a semiconductor integrated circuit.

[0035] The teaching device 4 further includes a command selection unit 41, a program editing unit 42, and a command editing unit 43. Although not essential, the teaching device 4 may further include a simulation generation unit 46, a machine operation unit 44, and a program generation unit 47. These "units" are made up of one or more programs or program sections that make up program creation software. The program creation software is read and executed by a processor such as a PLC (programmable logic controller), CPU (central processing unit), or MPU (micro processing unit).

[0036] The UI unit 40 displays and inputs various information. The command selection unit 41 selects various control commands based on operation information input via the UI unit 40. The program editing unit 42 arranges the control commands in chronological order based on the operation information input via the UI unit 40, and edits the operation program for the machine 2. The command editing unit 43 edits each control command based on the operation information input via the UI unit 40.

[0037] The simulation generation unit 46 places a model of the machine 2 in a virtual space and generates a simulation of the operation of the machine 2. The simulation generation unit 46 may also generate a motion trajectory and various coordinate axes of the machine 2. The machine operation unit 44 operates and moves the model of the machine 2 placed in the virtual space based on operation information input at the UI unit 40. The machine operation unit 44 may also generate a motion trajectory of the machine 2.

[0038] The memory unit 45 stores various information such as operation programs and parameters. The program generation unit 47 generates an operation program by converting the edited operation program into source code, object code (machine language), intermediate code, byte code, etc. The program generation unit 47 executes the generated operation program online or offline. The communication control unit 48 controls the communication of various information such as operation programs, control commands, parameters, and detection information from the force detector 18 and the motion detector 21 with the machine 2 or the control device 3.

[0039] The control device 3 comprises a machine operation unit 30 and a control unit 31. The machine operation unit 30 is composed of a teaching operation panel and is equipped with movement buttons, attitude change buttons, etc. for operating the machine 2. The control unit 31 is composed of a program or program section that can be executed by a PLC or other processor. The machine operation unit 30 operates the machine 2 based on operation information to actually move the machine 2. The control unit 31 drives and controls the actuator 20 in accordance with the operation program, control command, operation information, etc. to move the machine 2.

[0040] The machine 2 is equipped with one or more actuators 20, one or more motion detectors 21, and one or more force detectors 18. The actuators 20 drive the links 11 to 16 of the machine 2 in accordance with motion commands (position commands, speed commands, and current commands) from the control unit 31. The motion detectors 21 detect the motion (position, speed, and acceleration) of the actuators 20. The force detectors 18 detect forces acting on the tip of the machine 2, but are not limited to this, and in other embodiments, they detect torques acting on the links 11 to 16.

[0041] The command editing unit 43 has a registration unit 43a, a teaching unit 43b, a test execution unit 43c, and an adjustment unit 43d as editing functions for force control commands. The registration unit 43a, the teaching unit 43b, the test execution unit 43c, and the adjustment unit 43d are configured as one or more programs or program sections that make up the program creation software.

[0042] The registration unit 43a registers in advance, as initial values, other parameters other than the force parameters of the force control command and the motion trajectory T of the machine 2. The other parameters include the approach speed of the machine 2 to the work object W, the movement speed of the machine 2, the attitude of the machine 2, etc.

[0043] The teaching unit 43b uses the force detector 18 to link the force parameters of the force control command with the motion trajectory T of the machine 2 performing force control, and teaches them simultaneously. The teaching unit 43b is equipped with a teaching start command that starts recording the teaching, and a teaching end command that ends recording the teaching. When the teaching unit 43b starts recording the teaching, it starts recording the force parameters, the motion trajectory T, and other parameters by direct teaching or playback teaching. When the teaching unit 43b ends recording the teaching, it ends recording the force parameters, the motion trajectory T, and other parameters.

[0044] When teaching is performed using direct teaching, the instructor directly moves the controlled part of the machine 2 or a handle attached near the controlled part to press the tool 19 against the work object W and move it, while the teaching unit 43b obtains detection information from the force detector 18 from the control device 3 or the machine 2, and determines the magnitude and direction of the force to be applied to the work object W from the detection information, and determines the motion trajectory T of the machine 2 from the current position of the machine 2 and the direction of force action, and links the force parameters to the motion trajectory T and records them in the memory unit 45.

[0045] Alternatively, although it is different from the spirit of the present application, the motion trajectory T of the machine 2 may be obtained using the motion detector 21 or the visual sensor 17. In other words, the teaching unit 43b may obtain the motion trajectory T of the machine 2 based on forward kinematics from the detection information of the motion detector 21, or may obtain the motion trajectory T of the machine 2 geometrically from the detection information of the visual sensor 17 that captures images of three or more reference points whose relative positions are known.

[0046] When teaching is performed using playback teaching, the instructor actually operates the machine 2 using the machine operating unit 30 of the control device 3, pressing the tool 19 against the workpiece W and moving it, while the teaching unit 43b acquires detection information from the force detector 18 from the control device 3 or the machine 2, and determines the magnitude and direction of the force to be applied to the workpiece W from the detection information, and determines the motion trajectory T of the machine 2 from the current position of the machine 2 and the direction of force action, and links the force parameters and motion trajectory T and records them in the memory unit 45.

[0047] Alternatively, although different from the spirit of the present application, the motion trajectory T of the machine 2 may be obtained from the actual movement amount of the machine 2 by the machine operation unit 30, or may be obtained from the movement amount of a model of the machine 2 by the machine operation unit 44.

[0048] As described above, the teaching unit 43b uses the force detector 18 to link the force parameters of the force control command with the motion trajectory T of the machine 2 that performs force control and teaches them simultaneously, making it easy to teach even force control commands that tend to require a large number of teaching points. In particular, when teaching by direct teaching, the force parameters and motion trajectory T can be taught intuitively, and the instructor does not need to have knowledge of coordinate systems, etc., reducing the effort required for teaching.

[0049] The teaching unit 43b links the force parameters to the movement trajectory T for each teaching point that constitutes the movement trajectory T, or for each predetermined movement section that constitutes the movement trajectory T, or for each predetermined time interval during the movement, and records the linked force parameters. When linking the force parameters to the movement trajectory T for each teaching point, the instructor can flexibly adjust the force parameters for each teaching point. When linking the force parameters to the movement trajectory T for each predetermined movement section or for each predetermined time interval, the instructor can adjust the force parameters all at once for each predetermined movement section or for each predetermined time interval.

[0050] The teaching unit 43b may switch the interval (every teaching point, or every predetermined motion section, or every predetermined time interval) at which the force parameters are linked to the motion trajectory T based on the operation information input via the UI unit 40. By switching the interval at which the force parameters are linked to the motion trajectory T, the force parameters can be adjusted more flexibly, and the work efficiency of teaching force control commands is improved.

[0051] The teaching unit 43b may use the force detector 18 to simultaneously teach parameters other than the force parameter and the motion trajectory T. The parameters include the approach speed of the machine 2 to the workpiece W, the movement speed of the machine 2, the attitude of the machine 2, etc. The parameters are simultaneously taught by direct teaching or playback teaching. Teaching a force control command becomes even easier by simultaneously teaching parameters other than the force parameter and the motion trajectory T.

[0052] Alternatively, although it is different from the spirit of the present application, in the case of direct teaching, other parameters such as the approach speed of the machine 2, the movement speed of the machine 2, and the attitude of the machine 2 may be taught using the motion detector 21 or the visual sensor 17. Furthermore, in the case of playback teaching, other parameters such as the approach speed of the machine 2, the movement speed of the machine 2, and the attitude of the machine 2 may be found and taught from the actual movement amount of the machine 2 by the machine operation unit 30 or the movement amount of a model of the machine 2 by the machine operation unit 44.

[0053] The test execution unit 43c test-executes the taught force control command. The taught force control command is test-executed online or offline. When test-executing online, the test execution unit 43c sends the force control command to the control unit 31 via the communication control unit 48, and the control unit 31 drives the actuator 20 of the machine 2 in accordance with the force control command to actually operate the machine 2 and force-control the machine 2. The instructor checks the test results (processing results, operating trajectory T of the machine 2, cycle time, etc.), and if there are no problems with the test results, completes the teaching of the force control command, or if there are no problems with the test results, adjusts the teaching of the force control command.

[0054] When performing a test offline, the test execution unit 43c sends a force control command to the simulation generation unit 46, which then operates a model of the machine 2 in virtual space in accordance with the force control command to force control the machine 2. In offline test execution, the instructor cannot check the machining results, but can check the motion trajectory, cycle time, etc. of the machine 2. If there are no problems with the test results, the instructor completes the teaching of the force control command, and if there are problems with the test results, the instructor adjusts the teaching of the force control command.

[0055] The adjustment unit 43d manually or automatically adjusts the force parameters, movement trajectories, and other parameters that require adjustment. In the case of manual adjustment, the adjustment unit 43d manually adjusts various parameters for each teaching point, for each predetermined movement section, or for each predetermined time interval based on operation information input via the UI unit 40. In the case of automatic adjustment, the adjustment unit 43d automatically adjusts various parameters for each teaching point, for each predetermined movement section, or for each predetermined time interval by direct teaching or playback teaching.

[0056] When re-teaching one teaching point by direct teaching, the control unit 31 moves the control point P of the machine 2 to a specified teaching point, and then the instructor directly moves the controlled part of the machine 2 or a handle attached near the controlled part to press the tool 19 against the work object W, while the adjustment unit 43d obtains detection information from the force detector 18 from the control device 3 or the machine 2 and records the force parameters calculated from the detection information, thereby re-teaching.

[0057] When re-teaching multiple teaching points that make up a predetermined motion section or a predetermined time interval by direct teaching, the control unit 31 moves the control point P of the machine 2 to the starting point of the multiple teaching points, and then the instructor directly moves the controlled portion of the machine 2 or a handle attached near the controlled portion to press the tool 19 against the workpiece W and move it, while the adjustment unit 43d acquires detection information from the force detector 18 from the control device 3 or the machine 2 and records the force parameters, motion trajectory T, and other parameters calculated from the detection information, thereby re-teaching. The motion trajectory T and other parameters may also be re-taught using the motion detector 21 or the visual sensor 17.

[0058] When one teaching point is to be re-taught by playback teaching, the control unit 31 moves the control point P of the machine 2 to a specified teaching point, and then the instructor actually moves the machine 2 using the machine operation unit 30 to press the tool 19 against the workpiece W, while the adjustment unit 43d obtains the detection information of the force detector 18 from the control device 3 or the machine 2 and records the force parameters calculated from the detection information, thereby re-teaching.

[0059] When a plurality of teaching points constituting a predetermined operation section or a predetermined time interval are re-taught by playback teaching, the control unit 31 moves the control point P of the machine 2 to the starting point of the plurality of teaching points, and then while the instructor actually moves the machine 2 with the machine operation unit 30 and presses the tool 19 against the workpiece W to move it, the adjustment unit 43d acquires detection information from the force detector 18 from the control device 3 or the machine 2 and records the force parameters, operation trajectory T, other parameters, etc. calculated from the detection information, thereby performing re-teachment. The operation trajectory T and other parameters of the machine 2 may also be re-taught using the amount of movement by the machine operation unit 30 or the machine operation unit 44.

[0060] The test execution unit 43c tests the adjusted force control command again. The adjusted force control command is test-executed online or offline. The teacher checks the test results (machining results, operation trajectory T of the machine 2, cycle time, etc.), and if there are no problems with the test results, completes the teaching of the force control command, and if there are no problems with the test results, readjusts the teaching of the force control command.

[0061] After the force control teaching is completed, the program generation unit 47 generates an operation program for the machine 2 based on the taught force control command. The program generation unit 47 sends the generated operation program to the control unit 31, and the control unit 31 operates the machine 2 in accordance with the operation program to perform force control of the machine 2.

[0062] A teaching method for force control and an example of a program creation screen will be described below. Fig. 3 is an explanatory diagram illustrating an example of a teaching method for force control, and Figs. 4 to 6 show examples of a program creation screen 5 for force control. Note that Fig. 6 is a partially reduced and partially enlarged view of the program creation screen 5 in Fig. 5, and some of the text on the program creation screen 5 in Fig. 5 has been omitted in Fig. 6. In this example, it is assumed that an instructor O uses a force detector 18 to simultaneously teach the force parameters of a force control command, the motion trajectory of the machine 2, and other parameters by direct teaching, as shown in Fig. 3.

[0063] The instructor O starts up programming software that creates an operation program for the machine 2 using the teaching device 4. As shown in FIG. 4 , the programming software displays a program creation screen 5 on the UI unit 40. The program creation screen 5 includes a command selection window 52, ​​a program editing window 51, and a command editing window 54. Although not shown, the command selection window 52 is displayed on the program creation screen 5 by the command selection unit 41. The program editing window 51 is displayed on the program creation screen 5 by the program editing unit 42. The command editing window 54 is displayed on the program creation screen 5 by the command editing unit 43.

[0064] Although not required, the program creation screen 5 may include a simulation window 50, a machine operation window 56, and a program execution window 80. The simulation window 50 is displayed on the program creation screen 5 by the simulation generation unit 46. The machine operation window 56, not shown, is displayed on the program creation screen 5 by the machine operation unit 44. The program execution window 80, not shown, is displayed on the program creation screen 5 by the program generation unit 47.

[0065] The command selection window 52 displays various selectable control commands. The instructor O selects an icon 53 representing a force control command from the various control commands in the command selection window 52 and places the icon 53 in the program editing window 51. In another embodiment, the instructor O may select text representing a force control command from the various control commands in the command selection window 52 and place the text in the program editing window 51.

[0066] The program editing window 51 displays an operation program in which the arrangement of various control commands can be edited. The instructor O selects an icon 53 representing a force control command in the program editing window 51 to display a command editing window 54. In another embodiment, the instructor O may select text representing a force control command in the program editing window 51 to display the command editing window 54.

[0067] The command editing window 54 includes various editing functions for the control command selected in the program editing window 51. The command editing window 54 displays a teaching function, a test execution function, and a teaching adjustment function as editing functions for the force control command. The command editing window 54 may also display a registration function as an editing function for the force control command. The teaching function is displayed in the command editing window 54 by the teaching unit 43b. The test execution function is displayed in the command editing window 54 by the test execution unit 43c. The teaching adjustment function is displayed in the command editing window 54 by the adjustment unit 43d. The registration function is displayed in the command editing window 54 by the registration unit 43a.

[0068] The teaching function is equipped with a teaching button 55 that starts or ends teaching of a force control command. The teaching button 55 includes a teaching start button 55a that starts recording the teaching and a teaching end button 55b that ends recording the teaching. When teaching by direct teaching, the instructor O presses the teaching start button 55a, and then holds the wrist of the machine 2 and moves the tool 19 against the workpiece W, as shown in FIG. 3. When teaching by playback teaching, the instructor O operates the machine 2 with the machine control unit 30, as shown in FIG. 2, to move the tool 19 against the workpiece W.

[0069] While the machine 2 is moving, detection information from the force detector 18 is acquired, and the force parameters of the force control command are linked to the motion trajectory of the machine 2 and recorded simultaneously. In addition to the force parameters and motion trajectory, other parameters (such as the approach speed of the machine 2 to the work object W, the movement speed of the machine 2, and the posture of the machine 2) are also recorded simultaneously. The instructor O presses the teaching end button 55b to end the teaching of the force control command.

[0070] The test execution function is provided with a test execution button 57 for testing the taught force control command. The instructor O presses the test execution button 57 to test-execute the taught force control command. When performing an online test, the control device 3 actually operates the machine 2 in accordance with the force control command to force-control the machine 2. The instructor O checks the test results (machining results, operating trajectory of the machine 2, cycle time, etc.).

[0071] When a test is performed offline, the simulation generation unit 46 operates the model of the machine 2 in the virtual space of the simulation window 50 in accordance with the force control command to force-control the model of the machine 2. The instructor O cannot check the machining results, but can check the motion trajectory, cycle time, etc. of the machine 2. Although not required, the simulation window 50 may also display the motion trajectory of the machine 2, teaching points that make up the motion trajectory, various coordinate systems, the work object W, etc.

[0072] The teaching adjustment function includes a teaching completion option button 58 for selecting completion of teaching of the force control command, and a teaching adjustment option button 59 for selecting adjustment of the teaching of the force control command. If there is no problem with the test results of the force control command, the teacher O selects the teaching completion option button 58 to complete the teaching of the force control command. On the other hand, if there is a problem with the test results of the force control command, the teacher O selects the teaching adjustment option button 59 to adjust the teaching of the force control command.

[0073] As shown in FIG. 5 , the teaching adjustment function includes a trajectory history table 60 containing the trajectory history of the taught force control command, and a trajectory history scroll bar 61 for scrolling through the trajectory history in the trajectory history table 60. When the instructor O selects the teaching adjustment option button 59, the trajectory history table 60 is displayed in the command editing window 54. The trajectory history table 60 includes the teaching point number, the position and orientation of the machine 2 at the teaching point (X, Y, and Z are coordinate values ​​of each coordinate axis corresponding to the position of the machine 2, and WPR is the amount of rotation around each coordinate axis corresponding to the orientation of the machine 2), the magnitude of the force applied to the workpiece W (Newtons (N)), and the direction of action of the force applied to the workpiece W (positive or negative direction of a predetermined coordinate axis). Note that the trajectory history table 60 may include other parameters, such as the approach speed of the machine 2 relative to the workpiece W and the travel speed of the machine 2, for each teaching point. Alternatively, the registration function may include a separate parameter registration window (not shown) in which initial values ​​of the other parameters are registered in advance.

[0074] Although the magnitude and direction of force are linked to the motion trajectory for each teaching point, the trajectory history table 60 may also link force parameters to the motion trajectory for each predetermined motion section or for each predetermined time interval. The teaching function may also include multiple interval option buttons for switching the interval at which force parameters are linked to the motion trajectory. Since there tends to be a large number of teaching points for force control commands, the instructor O slides the trajectory history using the trajectory history scroll bar 61 to view the trajectory history and selects one or more teaching points that require adjustment from the trajectory history table 60. Although not shown, the instructor O may also select one or more teaching points by selecting a predetermined motion section or a predetermined time interval.

[0075] The text color or background color of the parameters of the selected teaching point is highlighted in the trajectory history table 60. The instructor O manually or automatically adjusts various parameters of the machine 2, such as the position and posture, the magnitude and direction of the force, at one or more selected teaching points.

[0076] The teaching adjustment function includes a teaching point selection list 62 for selecting a teaching point, a force adjustment box 63 for manually adjusting the magnitude of the force, and an action direction adjustment box 64 for manually adjusting the direction in which the force is applied. Although not shown, the teaching adjustment function may also include an approach speed adjustment box for manually adjusting the approach speed to the work object W, and a movement speed adjustment box for manually adjusting the movement speed of the machine 2. When the instructor O selects one or more teaching points that require adjustment in the trajectory history table 60, the magnitude and direction of the force applied at the selected one or more teaching points are displayed in the force adjustment box 63 and the action direction adjustment box 64, respectively. The instructor O re-teaches by manually adjusting the magnitude and direction of the force in the force adjustment box 63 and the action direction adjustment box 64, respectively.

[0077] The teaching adjustment function has a position and attitude adjustment box display button 67 that displays a position and attitude adjustment box 70 for manually adjusting the position and attitude of the machine 2, as shown in Fig. 6. When the teacher O selects one or more teaching points that need to be adjusted in the trajectory history table 60, the position and attitude adjustment box display button 67 is displayed. When the teacher O presses the position and attitude adjustment box display button 67, the position and attitude of the machine 2 at the selected one or more teaching points are displayed in the position and attitude adjustment box 70. The teacher O manually adjusts the position and attitude of the machine 2 in the position and attitude adjustment box 70.

[0078] Although not essential, the teaching adjustment function may be provided with coordinate system selection boxes 68 and 69 for selecting the numbers of the user coordinate system and the tool coordinate system, respectively. The instructor O selects the desired user coordinate system and the desired tool coordinate system in the coordinate system selection boxes 68 and 69.

[0079] The teaching adjustment function may be provided with an automatic adjustment button 65 that automatically adjusts the magnitude and direction of force, the position and attitude of the machine 2, and other parameters at one or more selected teaching points. The automatic adjustment is performed by direct teaching or playback teaching.

[0080] When re-teaching a selected teaching point by direct teaching, the instructor O presses the automatic adjustment button 65 to move the control point P of the machine 2 to the selected teaching point, and then the instructor O holds the wrist of the machine 2 and presses the tool 19 against the workpiece W, while acquiring detection information from the force detector 18 and recording the magnitude and acting direction of the force to be applied to the workpiece W determined from the detection information, thereby re-teaching. The magnitude and acting direction of the re-taught force are reflected in the trajectory history table 60, the force adjustment box 63, and the acting direction adjustment box 64, respectively.

[0081] When re-teaching multiple selected teaching points by direct teaching, the instructor O presses the automatic adjustment button 65 to move the control point P of the machine 2 to the starting point of the selected multiple teaching points, and then holds the wrist of the machine 2 and moves the tool 19 while pressing it against the workpiece W, while acquiring detection information from the force detector 18 and recording the magnitude and acting direction of the force calculated from the detection information, the motion trajectory of the machine 2, and other parameters. The motion trajectory and other parameters may also be re-taught using the motion detector 21 or the visual sensor 17. The re-taught magnitude and acting direction of the force, the motion trajectory, and other parameters are reflected in the trajectory history table 60, the force adjustment box 63, the action direction adjustment box 64, and the position and attitude adjustment box 70, respectively.

[0082] When a selected teaching point is to be re-taught by playback teaching, the instructor O presses the automatic adjustment button 65 to move the control point P of the machine 2 to the selected teaching point, and then the instructor O actually moves the machine 2 using the machine operation unit 30 of the control device 3 to press the tool 19 against the workpiece W, while the adjustment unit 43d acquires detection information from the force detector 18 and records the magnitude and acting direction of the force applied to the workpiece W, thereby re-teaching. The magnitude and acting direction of the re-taught force are reflected in the trajectory history table 60, the force adjustment box 63, and the acting direction adjustment box 64, respectively.

[0083] When re-teaching selected teaching points using playback teaching, the instructor O presses the automatic adjustment button 65 to move the control point P of the machine 2 to the starting point of the selected teaching points. Then, the instructor O holds the wrist of the machine 2 and moves the tool 19 while pressing it against the workpiece W. While the instructor O moves the tool 19, the adjustment unit 43d acquires detection information from the force detector 18 and records the magnitude and direction of the force applied to the workpiece W, the motion trajectory of the machine 2, and other parameters. The motion trajectory and other parameters may be re-taught using the amount of movement performed by the machine operation unit 30 or the machine operation unit 44. Although not shown, the machine operation unit 44 displays movement buttons, posture change buttons, and other buttons for operating the model of the machine 2 in the simulation window 50 in the machine operation window 56. The re-taught magnitude and direction of the force, the motion trajectory of the machine 2, and other parameters are reflected in the trajectory history table 60, the force adjustment box 63, the action direction adjustment box 64, and the position and posture adjustment box 70, respectively.

[0084] The teaching adjustment function may be provided with a comment input box 66 for inputting any comment for one or more teaching points. If the instructor O manually adjusts various parameters of the force control command, he / she may input a comment such as "manual adjustment" in the comment input box 66, and if the adjustment is automatic, he / she may input a comment such as "automatic adjustment" in the comment input box 66. This makes it possible to identify whether the parameters of the force control command have been adjusted manually or automatically.

[0085] After adjusting various parameters of the force control command, the instructor O presses the test execution button 57 to test-execute the adjusted force control command again. When testing again online, the control device 3 actually operates the machine 2 in accordance with the force control command to force-control the machine 2. The instructor O checks the test results (machining results, operating trajectory of the machine 2, cycle time, etc.).

[0086] When performing another offline test, the simulation generation unit 46 operates the model of machine 2 in the virtual space of the simulation window 50 in accordance with the force control command, thereby force-controlling the model of machine 2. The instructor O cannot check the machining results, but can check the motion trajectory, cycle time, etc. of machine 2. If there are no problems with the test results of the force control command, the instructor O selects the teaching completion option button 58 to complete the teaching of the force control command. On the other hand, if there are again problems with the test results of the force control command, the instructor O adjusts the teaching of the force control command again.

[0087] After the instructor O selects the teaching completion option button 58 to complete the teaching of the force control command, the instructor O generates and executes an operation program in the program execution window 80. The operation program is executed online or offline. When executed online, the control device 3 actually operates the machine 2 in accordance with the generated operation program to force-control the machine 2. When executed offline, the simulation generation unit 46 operates a model of the machine 2 in the virtual space of the simulation window 50 in accordance with the generated operation program to force-control the model of the machine 2.

[0088] An example of a method for teaching force control will be described below. FIG. 7 is a flowchart showing an example of a method for teaching force control. This flowchart is implemented by program creation software. The program editing unit 42 adds an icon 53 corresponding to a force control command to the program editing window 51 (step S10). The teaching unit 43b uses the force detector 18 to associate and simultaneously teach the force parameters, motion trajectories, and other parameters (step S11). The test execution unit 43c test-executes the taught force control command (step S12).

[0089] The instructor O checks the test results and determines whether or not to adjust the teaching point of the force control command (step S13). If the adjustment of the teaching point of the force control command is not necessary (NO in step S13), the adjustment unit 43d completes the teaching of the force control command (step S17). If the adjustment of the teaching point of the force control command is necessary (YES in step S13), the adjustment unit 43d adjusts the teaching point manually or automatically (step S14).

[0090] The test execution unit 43c again test-executes the adjusted force control command (step S15). The instructor O checks the test results and determines whether or not the adjustment of the teaching point of the force control command is complete (step S16). If the adjustment of the teaching point of the force control command is not complete (NO in step S16), the adjustment of the teaching point of the force control command (step S14) and the test execution of the force control command (step S15) are repeated. If the adjustment of the teaching point of the force control command is complete (YES in step S16), the adjustment unit 43d completes the teaching of the force control command (step S17).

[0091] The configuration of the mechanical system 1 of the second embodiment will be described below. Fig. 8 is a functional block diagram of the mechanical system 1 of the second embodiment. The above-described force control teaching method may be implemented by program creation software executed by the control device 3, rather than by program creation software executed by the teaching device 4. In the second embodiment, the mechanical system 1 does not include the teaching device 4, and the control device 3 also includes the components of the teaching device 4 of the first embodiment. The control device 3 includes a control unit 31 instead of the communication control unit 48 of the teaching device 4 of the first embodiment, but may also include the communication control unit 48.

[0092] According to the various embodiments described above, the force parameters of the force control command and the motion trajectory of the machine performing the force control are linked and taught simultaneously using the force detector 18, so that teaching of force control can be easily performed.

[0093] The programs executed by the aforementioned processors, drive circuits, etc. may be provided by being recorded on a computer-readable non-transitory recording medium, such as a CD-ROM, or may be distributed via wired or wireless connections from a server device on a WAN (wide area network) or LAN (local area network).

[0094] Although various embodiments have been described herein, it should be recognized that the present invention is not limited to the above-described embodiments, but can be modified in various ways within the scope of the claims. [Explanation of symbols]

[0095] 1 Mechanical Systems 2 machines 3. Control device 4 Teaching device 5 Program creation screen 10 Link (Base) 11 Link (swivel body) 12 Links (Upper Arm) 13 Link (forearm) 14-16 links (wrist element) 17 Visual Sensor 18 Force detector 19 Tools 20 Actuator 21 Motion Detector 30 Machine operation section 31 Control Unit 40 User Interface Section 41 Instruction selection section 42 Program Editorial Department 43 Command Editorial Department 43a Registration Department 43b Teaching section 43c Test Execution Department 43d Adjustment section 44 Machine operation section 45 Storage section 46 Simulation Generation Unit 47 Program Generation Section 48 Communication control section 50 Simulation Window 51 Program Edit Window 52 Command Selection Window 53 Icon representing force control command 54 Command Editing Window 55 Teaching button 55a Teaching start button 55b Teaching end button 56 Machine operation window 57 Test execution button 58 Teaching completion option button 59 Teaching adjustment option button 60 Orbit History Table 61 Trajectory history scroll bar 62 Teaching point selection list 63 Force adjustment box 64 Action direction adjustment box 65 Auto Adjustment Button 66 Comment input box 67 Position and orientation adjustment box display button 68, 69 Coordinate system selection box 70 Position and Orientation Adjustment Box 80 Program Execution Window C1~C3 coordinate system J1~J6 axis L processing line P control point T motion trajectory W Work object

Claims

1. a teaching unit that uses a force detector to teach a force parameter of a force control command for a machine in association with a motion trajectory of the machine that performs force control; The teaching unit teaches parameters other than the force parameters and the motion trajectory, and the parameters include at least one of an approach speed of the machine to a work object and a movement speed of the machine.

2. The teaching device according to claim 1 , wherein the teaching unit records the force parameters in association with the motion trajectory by direct teaching or playback teaching.

3. The teaching device according to claim 1 , further comprising a test execution unit that tests the force control command.

4. The teaching device according to claim 1 , further comprising an adjustment unit that manually or automatically adjusts at least one of the force parameter, the motion trajectory, and other parameters.

5. The teaching device according to claim 1 , further comprising a registration unit that registers in advance parameters other than the force parameters and the motion trajectory as initial values.

6. The teaching device according to claim 1 , wherein the teaching unit includes a teaching start command for starting recording of a teaching, and a teaching end command for ending recording of a teaching.

7. 7. The teaching device according to claim 1, wherein the teaching unit associates the force parameters with the movement trajectory and records them for each teaching point constituting the movement trajectory, for each predetermined movement section constituting the movement trajectory, or for each predetermined time interval during the movement.

8. The teaching device according to claim 1 , wherein the teaching unit switches an interval at which the force parameter is linked to the motion trajectory.

9. The teaching device according to claim 1 , further comprising: a command editing unit that edits the force control command, the command editing unit comprising the teaching unit.

10. The teaching device according to claim 1 , further comprising a program generating unit that generates an operation program for the machine based on the force control command.

11. The teaching device according to claim 1 , wherein the force parameters include a magnitude and a direction of a force applied to a workpiece.

12. a teaching unit that uses a force detector to teach a force parameter of a force control command for a machine by linking it with a motion trajectory of the machine that performs force control; a program generation unit that generates an operation program for the machine based on the force control command; a control unit that operates the machine in accordance with the operation program and controls the force of the machine; Equipped with The control device, wherein the teaching unit teaches parameters other than the force parameters and the motion trajectory, and the parameters include at least one of an approach speed of the machine to a work object and a movement speed of the machine.

13. a machine equipped with a force detector; a teaching unit that uses the force detector to teach the machine by linking a force parameter of a force control command to the machine with a motion trajectory of the machine that performs force control; a program generation unit that generates an operation program for the machine based on the force control command; a control unit that operates the machine in accordance with the operation program and controls the force of the machine; Equipped with The teaching unit teaches parameters other than the force parameters and the motion trajectory, and the parameters include at least one of an approach speed of the machine to a work object and a movement speed of the machine.

14. A program editing unit that accepts addition of force control commands to a machine; a command editing unit that can teach or edit force parameters including the magnitude and acting direction of the force of the force control command in association with a motion trajectory of the machine; a display unit that displays information about the magnitudes, action directions, and motion trajectories of the plurality of linked forces of the taught or edited force control commands; A teaching device comprising:

15. The teaching device described in Claim 14, wherein the command editing unit causes the display unit to display a teaching button indicating the start or end of teaching of the force control command.

16. A teaching device as described in claim 15, which allows execution of teaching by direct teaching when it receives a press of the teaching button indicating the start of teaching.

17. A teaching device described in any one of claims 14 to 16, wherein the information is information in tabular form that shows teaching points indicating the motion trajectory and the magnitude and direction of action of the force corresponding to the teaching points.

18. The command editing unit displays an execution button for testing the force control command on the display unit, The teaching device according to claim 14 , wherein when the execution button is pressed, a test is executed based on the information.

19. A teaching device described in any one of claims 14 to 18, wherein the instruction editing unit causes the display unit to display a display for re-teaching or re-editing the information.

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