Multi-axis control device, multi-axis control system, tuning method, and program

Abstract

The purpose of the present invention is to provide a multi-axis control device (100) or the like capable of tuning a servo amplifier (200) of a plurality of axes. A multi-axis control device (100) for synchronously controlling a plurality of axes using a combination of one servo amplifier (200) and one servo motor (300) as one axis is provided with an instruction unit (103) for instructing the servo amplifier (200) to tune parameters set in the servo amplifier (200). The multi-axis control device (100) reduces the burden of maintenance by a user.

Description

Multi-axis control device, multi-axis control system, tuning method and program

[0001] The present disclosure relates to a multi-axis control device, a multi-axis control system, a tuning method, and a program.

[0002] In industrial settings, multi-axis control systems are used that have multiple axes, each of which is equipped with a single servo amplifier and a single servo motor, and that synchronize the multiple axes to perform positioning control, speed control, torque control, and the like, based on control commands from a multi-axis control device. Tuning of the servo amplifiers in a multi-axis control system has traditionally been performed using an adjustment device that is an external device to the multi-axis control system. For example, Patent Document 1 discloses a technique in which an adjustment device adjusts the control parameters of the servo amplifier for an axis selected by a user from among the multiple axes of the multi-axis control system.

[0003] Japanese Patent Application Laid-Open No. 2022-96537

[0004] As described above, in the conventional technology, tuning of the servo amplifier requires an adjustment device, and therefore tuning cannot be performed unless an adjustment device is available at the destination of the multi-axis control system, i.e., at the site where the multi-axis control system is operated. Therefore, if an adjustment device is not available at the operation site, even if deterioration occurs in the multi-axis control system or in a device to which the multi-axis control system is applied during operation, the servo amplifier cannot be tuned to compensate for the deterioration. To solve this problem, there is a need for technology that can tune the servo amplifier of a multi-axis control system without using an adjustment device.

[0005] The present disclosure has been made in consideration of the above circumstances, and aims to provide a multi-axis control device, a multi-axis control system, a tuning method, and a program capable of performing tuning on servo amplifiers for multiple axes.

[0006] In order to achieve the above-mentioned object, the multi-axis control device of the present disclosure is a multi-axis control device that controls multiple axes synchronously, with each axis being a combination of one servo amplifier and one servo motor, and is equipped with an instruction means that instructs the servo amplifier to tune parameters set in the servo amplifier.

[0007] According to the present disclosure, it is possible to provide a multi-axis control device, a multi-axis control system, a tuning method, and a program that are capable of performing tuning on servo amplifiers for multiple axes.

[0008] FIG. 1 is a diagram showing a multi-axis control system according to an embodiment. FIG. 2 is a block diagram showing a hardware configuration of a multi-axis control device according to an embodiment. FIG. 3 is a block diagram showing a functional configuration of a multi-axis control device according to an embodiment. FIG. 4 is a flowchart showing tuning processing according to an embodiment.

[0009] A multi-axis control system 1 according to an embodiment is a system for synchronously controlling multiple axes, with each axis being a combination of one servo amplifier and one servo motor. As shown in Fig. 1, the multi-axis control system 1 includes a multi-axis control device 100, multiple servo amplifiers 200, and multiple servo motors 300, and multiple mechanical elements 400 are connected to the multi-axis control system 1.

[0010] The multi-axis control device 100 is communicably connected to a servo amplifier 200 and a higher-level device such as a programmable controller (not shown). The servo amplifier 200 is communicably connected to a servo motor 300. A mechanical element 400 is mechanically connected to the servo motor 300.

[0011] The multi-axis control device 100 is a device that controls multiple axes in synchronization, with each axis being a combination of one servo amplifier and one servo motor. The multi-axis control device 100 is also called a motion controller. The multi-axis control device 100 generates commands for controlling the servo amplifiers 200 based on commands sent from a higher-level device and sends the commands to the servo amplifiers 200.

[0012] Furthermore, information for identifying the servo amplifiers 200 to be automatically tuned is stored in the multi-axis control device 100. The servo amplifiers 200 to be automatically tuned are arbitrarily designated by the user. The multi-axis control device 100 refers to the stored information and instructs the servo amplifiers 200 to be automatically tuned, among the servo amplifiers 200 included in the multi-axis control system 1, to perform tuning.

[0013] The servo amplifier 200 drives the servo motor 300 and tunes the servo amplifier 200 itself in accordance with commands from the multi-axis control device 100. The servo amplifier 200 also receives information indicating the operating state of the servo motor 300 from a sensor provided in the servo motor 300.

[0014] The servo motor 300 is driven by the servo amplifier 200 to operate a mechanical element 400 connected to the servo motor 300. The servo motor 300 also includes a sensor that detects the operating state of the servo motor 300, and the operating state is detected by the sensor at a predetermined cycle and transmitted to the servo amplifier 200.

[0015] The mechanical element 400 is connected to the multi-axis control system 1, and is mechanically connected to the servo motor 300. The mechanical element 400 is, for example, a ball screw, a belt, or a gear.

[0016] FIG. 2 shows an example of the hardware configuration of the multi-axis control device 100.

[0017] The multi-axis control device 100 has a processor 11 that executes various processes, a main memory unit 12 that is used as a work area for the processor 11, an auxiliary memory unit 13 that stores various data used in the processes of the processor 11, and a communication unit 14 for communicating with external devices. The main memory unit 12, the auxiliary memory unit 13, and the communication unit 14 are all connected to the processor 11 via a bus 15.

[0018] The processor 11 is a CPU (Central Processing Unit) having multiple cores. The processor 11 executes programs stored in the auxiliary storage unit 13 to realize various functions of the multi-axis control device 100.

[0019] The main memory unit 12 includes a RAM (Random Access Memory). Programs are loaded into the main memory unit 12 from the auxiliary memory unit 13. The main memory unit 12 is used as a working area for the processor 11.

[0020] The auxiliary storage unit 13 includes a non-volatile memory such as an EEPROM (Electrically Erasable Programmable Read-Only Memory). In addition to programs, the auxiliary storage unit 13 stores various data used in the processing of the processor 11. In accordance with instructions from the processor 11, the auxiliary storage unit 13 supplies the processor 11 with data used by the processor 11 and stores the data supplied from the processor 11.

[0021] The communication unit 14 includes a network interface circuit for communicating with an external device. The communication unit 14 receives a signal from the external device and outputs data indicated by the signal to the processor 11. The communication unit 14 also transmits a signal indicating the data output from the processor 11 to the external device.

[0022] Next, the functions of the multi-axis control device 100 will be described with reference to Fig. 3. The multi-axis control device 100 functionally includes an acquisition unit 101 that acquires information indicating deterioration of the multi-axis control system 1 or the mechanical element 400, a determination unit 102 that determines whether tuning is necessary, and an instruction unit 103 that instructs the servo amplifier 200 to perform tuning.

[0023] The following describes the functions of the multi-axis control device 100, taking as an example a case where the multi-axis control system 1 includes two servo amplifiers 200 and two servo motors 300 and controls two axes, and the multi-axis control device 100 transmits a position command to the servo amplifiers 200 to perform positioning control. The multi-axis control device 100 is assumed to be communicatively connected to the servo amplifiers 200-A and 200-B, the servo amplifiers 200-A are communicatively connected to the servo motors 300-A, and the servo amplifiers 200-B are communicatively connected to the servo amplifiers 200-B. The multi-axis control device 100 is also assumed to store information identifying the servo amplifiers 200-A and 200-B as the servo amplifiers 200 to be automatically tuned. It is also assumed that axis A, which is a combination of the servo amplifier 200-A and the servo motor 300-A, and axis B, which is a combination of the servo amplifier 200-B and the servo motor 300-B, are not mechanically connected.

[0024] Axes being mechanically connected means that the movement of one axis is somehow affected by the movement of the other axis, such as by interference with or restriction of the movement of the other axis due to the mechanical element 400. For example, when two axes are connected via a conveyor belt, the two axes are said to be mechanically connected. Since axis A and axis B are not mechanically connected, the multi-axis control device 100 can control axis A and axis B independently.

[0025] The acquiring unit 101 acquires information indicating the deterioration state of the multi-axis control system 1 including the multiple servo amplifiers 200, the multiple servo motors 300, and the multi-axis control device 100, or the mechanical elements 400 connected to the multi-axis control system 1. The acquiring unit 101 is realized by the processor 11 and the communication unit 14. The acquiring unit 101 is an example of an acquiring means.

[0026] Deterioration of the multi-axis control system 1 or the mechanical element 400 refers to, for example, a decrease in responsiveness to control commands. Continuous operation of the multi-axis control system 1 or the mechanical element 400 can cause mechanical deterioration due to friction, vibration, and the like, which can result in poor responsiveness to control commands. This decrease in responsiveness affects the value of the accumulated pulse, which is the difference between the feed pulse and the feedback pulse in the servo amplifier 200. Therefore, the value of the accumulated pulse, which is the difference between the feed pulse and the feedback pulse in the servo amplifier 200, is used as information indicating the state of deterioration of the multi-axis control system 1 or the mechanical element 400.

[0027] For example, the acquisition unit 101 acquires the values ​​of accumulated pulses from the servo amplifier 200 -A and the servo amplifier 200 -B included in the multi-axis control system 1 .

[0028] The determination unit 102 determines whether tuning is necessary based on the information indicating the state of deterioration. The determination unit 102 is realized by the processor 11 and the communication unit 14. The determination unit 102 is an example of a determination means.

[0029] Specifically, when the value of accumulated pulses acquired by the acquisition unit 101 exceeds a predetermined value, the determination unit 102 determines that tuning is required for the servo amplifier 200 for which the value of accumulated pulses that exceeds the predetermined value has been acquired. The predetermined value can be set arbitrarily by the user of the multi-axis control system 1.

[0030] For example, if the value of accumulated pulses acquired from servo amplifier 200-A exceeds a predetermined value, determination unit 102 determines that tuning is required for servo amplifier 200-A.Also, for example, if the value of accumulated pulses acquired from servo amplifier 200-B does not exceed a predetermined value, determination unit 102 determines that tuning is not required for servo amplifier 200-B.

[0031] When the determination unit 102 determines that tuning is necessary, the instruction unit 103 instructs the servo amplifier to tune the parameters to be set in the servo amplifier. For example, the instruction unit 103 instructs the servo amplifier determined by the determination unit 102 that tuning is necessary to tune it. The instruction unit 103 is realized by the processor 11 and the communication unit 14. The instruction unit 103 is an example of an instruction means.

[0032] For example, the instruction unit 103 instructs the servo amplifier 200-A, which has been determined by the determination unit 102 to require tuning, to perform tuning. On the other hand, since the determination unit 102 has determined that tuning is not required for the servo amplifier 200-B, the instruction unit 103 does not instruct the servo amplifier 200-B to perform tuning.

[0033] Next, the tuning process according to this embodiment will be described with reference to FIGS.

[0034] FIG. 4 is a flowchart showing the tuning process that is executed when the servo motor is powered on or at a timing designated by the user during operation.

[0035] The instruction unit 103 of the multi-axis control device 100 transmits a tuning instruction to the servo amplifiers 200-A and 200-B connected to the multi-axis control device 100 (step S101).

[0036] When the servo amplifier 200-A receives the tuning instruction, it tunes the parameters set in the servo amplifier 200-A using a predetermined tuning pattern (step S102).When the servo amplifier 200-B receives the tuning instruction, it tunes the parameters set in the servo amplifier 200-B using a predetermined tuning pattern (step S103).

[0037] When the tuning is completed, the servo amplifier 200-A transmits a tuning completion notification to the multi-axis control device 100 (step S104). When the tuning is completed, the servo amplifier 200-B transmits a tuning completion notification to the multi-axis control device 100 (step S105).

[0038] When the instruction unit 103 of the multi-axis control device 100 receives a tuning completion notification from the servo amplifiers 200-A and 200-B to which the tuning instructions were sent (step S106), the tuning process of FIG. 4 ends.

[0039] 5 is a flowchart showing a tuning process that is periodically executed during operation of the multi-axis control system 1. The intervals at which the tuning process is periodically executed are not limited to a fixed interval and can be set arbitrarily by the user. The tuning process in FIG. 5 is also performed on the servo amplifier 200 that is designated as the target for automatic tuning.

[0040] The acquisition unit 101 of the multi-axis control device 100 transmits a request to acquire the value of accumulated pulses to the servo amplifiers 200-A and 200-B connected to the multi-axis control device 100 (step S201).

[0041] When the servo amplifier 200-A receives the request to acquire the value of the accumulated pulses, it checks the value of the accumulated pulses of the servo amplifier 200-A (step S202). Also, when the servo amplifier 200-B receives the request to acquire the value of the accumulated pulses, it checks the value of the accumulated pulses of the servo amplifier 200-B (step S203). Then, the servo amplifier 200-A transmits a response including the confirmed value of the accumulated pulses to the multi-axis control device 100 (step S204). Also, the servo amplifier 200-B transmits a response including the confirmed value of the accumulated pulses to the multi-axis control device 100 (step S205).

[0042] The determination unit 102 of the multi-axis control device 100 determines whether tuning of the servo amplifiers is necessary based on whether the value of accumulated pulses acquired from the servo amplifiers 200-A and 200-B exceeds a predetermined value, and determines whether any servo amplifiers require tuning (step S206). If the determination unit 102 of the multi-axis control device 100 determines that any servo amplifiers require tuning (step S206; YES), the instruction unit 103 of the multi-axis control device 100 sends a tuning instruction to the servo amplifiers determined to require tuning (step S207).

[0043] For example, if the accumulated pulse values ​​acquired from the servo amplifiers 200-A and 200-B exceed a predetermined value, the determination unit 102 determines that tuning is required for the servo amplifiers 200-A and 200-B, and the instruction unit 103 sends a tuning instruction to the servo amplifiers 200-A and 200-B. Also, for example, if the accumulated pulse values ​​acquired from the servo amplifier 200-A exceed a predetermined value but the accumulated pulse values ​​acquired from the servo amplifier 200-B do not exceed the predetermined value, the determination unit 102 determines that tuning is required for the servo amplifier 200-A but does not require tuning for the servo amplifier 200-B. In this case, the instruction unit 103 sends a tuning instruction to the servo amplifier 200-A but does not send a tuning instruction to the servo amplifier 200-B. Therefore, the processes of steps S209 and S211 are omitted.

[0044] On the other hand, if the determining unit 102 of the multi-axis control device 100 determines that there is no servo amplifier that requires tuning (step S206; NO), the tuning process of FIG. 5 ends.

[0045] For example, if the accumulated pulses acquired from the servo amplifiers 200-A and 200-B do not exceed a predetermined value, the judgment unit 102 determines that tuning is not required for the servo amplifiers 200-A and 200-B, and the tuning process of Figure 5 ends.

[0046] When the servo amplifier 200-A receives the tuning instruction, it tunes the parameters set in the servo amplifier 200-A using a predetermined tuning pattern (step S208).When the servo amplifier 200-B receives the tuning instruction, it tunes the parameters set in the servo amplifier 200-B using a predetermined tuning pattern (step S209).

[0047] When the tuning is completed, the servo amplifier 200-A transmits a tuning completion notification to the multi-axis control device 100 (step S210). When the tuning is completed, the servo amplifier 200-B transmits a tuning completion notification to the multi-axis control device 100 (step S211).

[0048] For example, when servo amplifier 200-A and servo amplifier 200-B receive a tuning instruction from multi-axis control device 100, they tune the parameters set in servo amplifier 200-A and servo amplifier 200-B, and after tuning is completed, they send a tuning completion notification to multi-axis control device 100.

[0049] When the instruction unit 103 of the multi-axis control device 100 receives a tuning completion notification from the servo amplifier that sent the tuning instruction (step S212), the tuning process in Fig. 5 ends. For example, if the instruction unit 103 of the multi-axis control device 100 sends a tuning instruction to the servo amplifier 200-A and the servo amplifier 200-B, the tuning process in Fig. 5 ends when the instruction unit 103 receives a tuning completion notification from the servo amplifier 200-A and the servo amplifier 200-B that sent the tuning instruction.

[0050] In the past, tuning a servo amplifier required an adjustment device that was external to the multi-axis control system. Therefore, tuning of the servo amplifier was possible only when the adjustment device was available, such as before shipping the multi-axis control system or when installing a device with mechanical elements connected to the multi-axis control system. However, according to this embodiment, tuning of the servo amplifiers for multiple axes can be performed without using an adjustment device that is external to the multi-axis control system. As a result, even if deterioration occurs in the multi-axis control system or in a device to which a multi-axis control system is applied during operation, tuning can be performed at any time to compensate for the deterioration, thereby reducing the maintenance burden on the user.

[0051] Furthermore, according to this embodiment, it is possible to determine whether tuning is necessary based on the deterioration state of the multi-axis control system or the mechanical elements connected to the multi-axis control system, and to perform tuning if tuning is necessary. As a result, even if the multi-axis control system or the mechanical elements connected to the multi-axis control system deteriorate, tuning can be performed autonomously to maintain performance.

[0052] Furthermore, according to this embodiment, tuning is performed automatically based on the deterioration state of the multi-axis control system or the mechanical elements connected to the multi-axis control system, so the user can avoid the work of setting parameters for the servo amplifiers of multiple axes and selecting the servo amplifiers to be tuned.

[0053] (Modifications) Although the embodiments of the present disclosure have been described above, various modifications and applications are possible when implementing the present disclosure.

[0054] In the above embodiment, an example was described in which axis A, which is a combination of servo amplifier 200-A and servo motor 300-A, and axis B, which is a combination of servo amplifier 200-B and servo motor 300-B, are not mechanically connected, but axis A and axis B may also be mechanically connected.

[0055] If the axis to be controlled is mechanically connected, the determination unit 102 may determine whether tuning is necessary based on information indicating the deterioration state and information indicating whether the axis is mechanically connected. The information indicating whether the axis is mechanically connected is arbitrarily specified by the user and stored in the multi-axis control device 100.

[0056] Specifically, when any of the multiple accumulated pulse values ​​acquired from multiple servo amplifiers 200 whose axes are mechanically connected exceeds a predetermined value, the judgment unit 102 judges that tuning is required for the servo amplifier 200 from which the accumulated pulse value exceeding the predetermined value was acquired and for the servo amplifier 200 whose axis is mechanically connected to that servo amplifier 200.

[0057] For example, when axis A and axis B are mechanically connected, if any of the values ​​of the plurality of accumulated pulses acquired by acquisition unit 101 exceeds a predetermined value, determination unit 102 determines that tuning is required for servo amplifiers 200-A and 200-B included in multi-axis control system 1. For example, if the value of accumulated pulses acquired from servo amplifier 200-A exceeds a predetermined value, but the value of accumulated pulses acquired from servo amplifier 200-B does not exceed the predetermined value, determination unit 102 determines that tuning is required for servo amplifiers 200-A and 200-B. Then, instruction unit 103 instructs servo amplifiers 200-A and 200-B to tune.

[0058] In addition, by applying an operating program that specifies the operation of the multi-axis control device 100 according to the above embodiment to an existing personal computer or information terminal device, it is also possible to make the personal computer or information terminal device function as the multi-axis control device 100 according to the embodiment.

[0059] Furthermore, the method of distribution of such a program is arbitrary; for example, it may be stored on a computer-readable recording medium such as a CD-ROM (Compact Disk Read-Only Memory), a DVD (Digital Versatile Disk), or a memory card and distributed, or it may be distributed via a communication network such as the Internet.

[0060] The present disclosure allows various embodiments and modifications without departing from the broad spirit and scope of the present disclosure. Furthermore, the above-described embodiments are intended to explain the present disclosure and do not limit the scope of the present disclosure. That is, the scope of the present disclosure is defined by the claims, not the embodiments. Various modifications made within the scope of the claims and the meaning of equivalent disclosures are considered to be within the scope of the present disclosure.

[0061] According to the present disclosure, it is possible to provide a multi-axis control device, a multi-axis control system, a tuning method, and a program that are capable of performing tuning on servo amplifiers for multiple axes.

[0062] 1 Multi-axis control system, 11 Processor, 12 Main memory unit, 13 Auxiliary memory unit, 14 Communication unit, 15 Bus, 100 Multi-axis control device, 101 Acquisition unit, 102 Determination unit, 103 Instruction unit, 200, 200-A, 200-B Servo amplifier, 300, 300-A, 300-B Servo motor, 400 Mechanical element.

Claims

1. A multi-axis control device that controls multiple axes synchronously, with one axis being the combination of one servo amplifier and one servo motor, and is equipped with an instruction means for instructing the servo amplifier to tune parameters set in the servo amplifier.

2. A multi-axis control device as described in claim 1, comprising: a multi-axis control system including a plurality of the servo amplifiers, a plurality of the servo motors, and the multi-axis control device, or an acquisition means for acquiring information indicating a deterioration state of a mechanical element connected to the multi-axis control system; and a judgment means for judging whether or not the tuning is necessary based on the information indicating the deterioration state, wherein the instruction means instructs the servo amplifiers to perform the tuning when the judgment means judges that the tuning is necessary.

3. A multi-axis control device as described in claim 2, wherein the information indicating the deterioration state is a value of an accumulated pulse which is the difference between a feed pulse and a feedback pulse in the servo amplifier, the acquisition means acquires the values ​​of the accumulated pulse from the multiple servo amplifiers included in the multi-axis control system, and when the value of the accumulated pulse acquired by the acquisition means exceeds a predetermined value, the judgment means judges that the tuning is required for the servo amplifier for which the accumulated pulse value exceeding the predetermined value is acquired, and the instruction means instructs the tuning to be performed for the servo amplifier judged by the judgment means to be requiring the tuning.

4. A multi-axis control system comprising: a multi-axis control device according to any one of claims 1 to 3; the plurality of servo amplifiers; and the plurality of servo motors.

5. A tuning method in which a multi-axis control device, which synchronously controls multiple axes, with one axis being the combination of one servo amplifier and one servo motor, instructs the servo amplifier to tune parameters set in the servo amplifier.

6. A program that causes a computer, which controls multiple axes synchronously, with one axis being the combination of one servo amplifier and one servo motor, to function as an instruction means for instructing the servo amplifier to tune the parameters set in the servo amplifier.

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