Adjustment-support method, program, and adjustment-support system

Abstract

The present invention allows a user to grasp a cause accurately and easily, when a change occurs in an operation of a servo motor after adjustment of a control device. In an adjustment-support method for the control device (3) related to the servo motor (M1), the control device (3) includes a feedback control unit that gives, to the servo motor (M1), a torque instruction for reducing a difference between a position instruction and a motor position. The adjustment-support method has an adjustment-condition designation step, a frequency-characteristic measurement step, a parameter adjustment step, and a parameter holding step. In the adjustment-condition designation step, an operation range in adjustment of the servo motor (M1) and an adjustment condition as a target are designated. In the parameter adjustment step, the servo motor (M1) is operated, and an evaluation index value is calculated by adjusting control parameters of the feedback control unit on the basis of estimation of device characteristics, front-wavenumber characteristics, and the adjustment conditions. In the parameter holding step, the control parameter and the evaluation index value are held in association with the device characteristics and frequency characteristics.

Description

Adjustment support method, program, and adjustment support system

[0001] The present disclosure relates to an adjustment support method, a program, and an adjustment support system, and more particularly to an adjustment support method, a program, and an adjustment support system for a control device that controls a servo motor.

[0002] Servomotors are generally used as the driving source for drive units in production equipment that require high-speed or high-precision operation. To control the position of the drive unit, servomotors use feedback control based on a command pattern, which is an operational instruction from a host controller, to ensure that the positions of the motor and drive unit match the positions on the command pattern. This control involves multiple control parameters. To achieve the required high-speed or high-precision operation, these control parameters must be appropriately adjusted to match the characteristics of the motor and drive unit, and parameter calculation methods and parameter adjustment devices have been disclosed.

[0003] Patent Document 1 discloses a method for calculating control parameters based on load frequency characteristics.

[0004] Patent Document 2 discloses an adjustment method for adjusting control parameters while driving a motor or a drive unit in accordance with a command pattern based on an initial setting.

[0005] By adjusting the control parameters based on these adjustment methods, the user can achieve the desired high speed or high precision operation of the drive unit.

[0006] JP 2005-245051 A JP 2019-37129 A

[0007] However, changes in the operation pattern of the drive unit can also change the results. Furthermore, drive unit operation depends not only on the control parameters but also on the characteristics of the drive unit. Therefore, if the device characteristics change due to changes in the individual drive unit, changes over time, or changes in the equipment design information, the drive unit operation will change even if the control parameters remain the same. When drive unit operation changes after adjustment, it may be necessary to investigate the cause and take appropriate measures. To do this, the operation pattern and drive unit characteristics when the control parameters are adjusted may be recorded and then compared with the operation pattern and drive unit characteristics after the drive unit operation change. However, it may be difficult for users to easily determine which information should be uniquely combined and saved. Furthermore, due to the possibility of errors in the saving process due to a lack of user knowledge or human error, it may not be possible to save valid and accurate data, including location and control parameters, etc. In such cases, it may take a long time to investigate the cause and take appropriate measures.

[0008] The present disclosure aims to provide an adjustment support method, program, and adjustment support system that enable a user to accurately and easily understand the cause of a change in servo motor operation when the change occurs after adjustment of a control device.

[0009] An adjustment support method according to one aspect of the present disclosure is a method for supporting adjustment of a control device that controls a servomotor. The control device includes a feedback control unit that provides the servomotor with a torque command to reduce a difference between a position command and the motor position. The adjustment support method includes an adjustment condition specification step, a device characteristic acquisition step, a frequency characteristic measurement step, a parameter adjustment step, and a parameter storage step. In the adjustment condition specification step, target adjustment conditions for adjusting the servomotor are specified. In the device characteristic acquisition step, device characteristics of a device including the servomotor are acquired. In the frequency characteristic measurement step, frequency characteristics of the motor position relative to the position command are measured. In the parameter adjustment step, the servomotor is operated, and control parameters of the feedback control unit are adjusted based on the device characteristics, frequency characteristics, and adjustment conditions to calculate an evaluation index value. In the parameter storage step, the control parameters are stored in association with the device characteristics, frequency characteristics, and evaluation index value.

[0010] A program according to one aspect of the present disclosure causes one or more processors to execute an adjustment assistance method.

[0011] An adjustment support system according to one aspect of the present disclosure is an adjustment support system for a control device that controls a servo motor. The control device includes a feedback control unit that provides the servo motor with a torque command to reduce a difference between a position command and the motor position. The adjustment support system includes an adjustment condition designation unit, a device characteristic acquisition unit, a frequency characteristic measurement unit, a parameter adjustment unit, and a parameter storage unit. The adjustment condition designation unit designates target adjustment conditions for adjusting the servo motor. The device characteristic acquisition unit acquires device characteristics of a device that includes the servo motor. The frequency characteristic measurement unit measures frequency characteristics of the motor position relative to the position command. The parameter adjustment unit operates the servo motor and adjusts control parameters of the feedback control unit based on the device characteristics, frequency characteristics, and adjustment conditions to calculate an evaluation index value. The parameter storage unit stores the control parameters in association with the device characteristics, frequency characteristics, and evaluation index value.

[0012] According to an adjustment support method, a program, and an adjustment support system according to one aspect of the present disclosure, when a change occurs in servo motor operation after adjustment of a control device, the user can accurately and easily understand the cause.

[0013] Fig. 1 is a configuration diagram of an entire system including an adjustment support system and a drive system according to an embodiment. Fig. 2 is a block diagram of the drive system according to an embodiment. Fig. 3A is a block diagram of a communication terminal in which the functions of the adjustment support system according to an embodiment are implemented. Fig. 3B is a block diagram of the adjustment support system according to an embodiment. Fig. 4 is a schematic diagram showing an input screen for control parameters in the adjustment support system according to an embodiment. Fig. 5 is a flowchart showing the operation of the adjustment support system according to an embodiment.

[0014] Hereinafter, an adjustment support method, a program, and an adjustment support system according to embodiments will be described in detail with reference to the drawings. However, each diagram described in the following embodiments is a schematic diagram, and the ratios of the sizes and thicknesses of the components do not necessarily reflect the actual dimensional ratios. Note that the configurations described in the following embodiments are merely examples of the present disclosure. The present disclosure is not limited to the following embodiments, and various modifications are possible depending on the design, etc., as long as the effects of the present disclosure can be achieved.

[0015] (Embodiment) (1) Configuration FIG. 1 is a block diagram showing the configuration of an adjustment support system 1 and a drive system 2 according to an embodiment.

[0016] (1.1) Drive System The drive system 2 includes a servo motor M1, a load 4, a position detector 5, and a control device 3. The drive system 2 receives an operation command, which is an operation pattern, from a higher-level controller 6 or an adjustment support system 1, and controls the operation of the servo motor M1 to thereby control the operation of the load 4.

[0017] The servo motor M1 is a rotary motor having an output shaft, and the output shaft is rotated by power supplied from the control device 3.

[0018] The load 4 is a drive unit mechanically connected to the servo motor M1, and is composed of, for example, a ball screw that rotates synchronously with the output shaft of the servo motor M1 by being coupled with the output shaft of the servo motor M1 by a coupling or the like, and a table that moves linearly by a ball screw mechanism.

[0019] The position detector 5 detects the rotation direction and position of the servo motor M1. The position detection signal indicates the position of the servo motor M1. The position of the servo motor M1 is a value indicating the angle and direction that the rotation shaft has rotated from a reference state to the current state. The position of the servo motor M1 is, for example, a value in which the angle is expressed as an absolute value and the direction is expressed as a sign. Specifically, for example, clockwise rotation is the positive direction and counterclockwise rotation is the negative direction, with the reference position being 0 degrees, one clockwise rotation from the reference position being 360 degrees, and two counterclockwise rotations from the reference position being -720 degrees.

[0020] (1.2) Control Device The control device 3 is communicably connected to the position detector 5 and receives a position detection signal from the position detector 5 .

[0021] The control device 3 determines the control value of the servo motor M1 based on the operation command and the detection result of the position detector 5, thereby controlling the operation of the servo motor M1 so that the operation command and the detection result of the position detector 5 match.

[0022] 2 is a block diagram of the drive system 2 according to the embodiment. As shown in FIG. 2, the control device 3 includes a position / speed control unit 30 and a current control unit 31.

[0023] The position / speed control unit 30 performs feedback control so that the movement amount (detection value) related to the position of the servo motor M1 from the position detector 5 coincides with the position command value (command value) of the servo motor M1 as an operation command from the upper controller 6, and outputs a torque command signal. The feedback control is implemented by, for example, a PID controller or a notch filter for suppressing the influence of mechanical resonance.

[0024] The current control unit 31 controls the power (drive current) supplied to the servo motor M1 so that the servo motor M1 generates torque according to the torque command signal received from the position / speed control unit 30. As a result, the servo motor M1 is driven, and the load 4 is also driven.

[0025] The control device 3 also has a function of executing a measurement operation for calculating the frequency characteristic of the motor speed relative to the torque command via the adjustment support system 1, and of calculating the frequency characteristic.

[0026] The control device 3 also has a function of estimating, as device characteristics, for example, the total inertia value of the servo motor M1 and the load 4, and the friction characteristic value acting on the servo motor M1 based on the motor operation. The friction characteristic value is, for example, a dynamic friction value. Here, the estimation of the total inertia value may be replaced by a function of estimating an inertia ratio, which is the ratio of the load inertia to the motor inertia.

[0027] In addition, the control device 3 has the function of adjusting or setting, via the adjustment support system 1, control parameters within the feedback control, such as the gain of PID control, which is a component of the feedback control, whether or not to use a notch filter, and their parameter values.

[0028] The control device 3 also includes, for example, a computer system having a processor and a memory. The computer system executes a program stored in the memory by the processor, thereby realizing at least some of the functions of the control device 3. The program may be pre-recorded in the memory of the computer system, may be provided by being recorded on a recording medium such as a memory card, or may be provided via a telecommunications line such as the Internet.

[0029] (1.3) Upper Controller The upper controller 6 is, for example, a programmable logic controller (PLC), and controls the operation of the control device 3. The upper controller 6 is, for example, capable of communicating with the control device 3.

[0030] The upper controller 6 includes, for example, a computer system having a processor and a memory. The computer system realizes at least a part of the functions of the upper controller 6 by causing the processor to execute a program stored in the memory. The program may be pre-recorded in the memory of the computer system, may be provided by being recorded on a recording medium such as a memory card, or may be provided via a telecommunications line such as the Internet.

[0031] (1.4) Adjustment Support System The adjustment support system 1 is included in the communication terminal 7 shown in Fig. 1. The communication terminal 7 is, for example, a notebook computer.

[0032] 3A is a block diagram of a communication terminal 7 in which the functions of the adjustment support system 1 according to the embodiment are implemented. The communication terminal 7 is communicably connected to the control device 3. As shown in FIG. 3A , the communication terminal 7 includes a display unit 70, a processing unit 71, an operation unit 72, and a storage unit 73. Note that the communication terminal 7 may not include the display unit 70 and may be connected to a display device.

[0033] The processing unit 71 has the functions of the adjustment support system 1. Details will be described later.

[0034] The display unit 70 is a display device, such as a liquid crystal display or an organic EL display.

[0035] The operation unit 72 is an input device that accepts input from the user, and may be, for example, a mouse or a keyboard. The operation unit 72 may be a touch panel that is integrated with the display unit 70.

[0036] The storage unit 73 is a storage medium that stores the above-mentioned device characteristics and frequency characteristics, as well as adjustment conditions and adjustment result information, which will be described later.

[0037] 3B is a block diagram of the adjustment support system 1 according to the embodiment. As shown in FIG. 3B , the adjustment support system 1 includes a parameter adjustment unit 11, an adjustment condition designation unit 12, a parameter storage unit 13, an apparatus characteristics acquisition unit 14, and a frequency characteristics measurement unit 15.

[0038] The adjustment condition designation unit 12 designates target adjustment conditions for adjusting the servo motor M1. More specifically, the adjustment condition designation unit 12 accepts input of adjustment conditions from a user. The adjustment conditions include, for example, an operating range in which the servo motor M1 is operated during adjustment, an evaluation index value that is a condition for desired operating performance, and a desired control margin of the feedback control system.

[0039] The evaluation index value includes, for example, one or more of a positioning settling time, an amount of overshoot, a performance evaluation value for a position deviation, and a performance evaluation value for a torque command in an operation.

[0040] The positioning settling time is the time required from the completion of output of an operation command from the upper controller 6 or the adjustment support system 1 until the absolute value of the difference between the position of the servo motor M1 indicated by the position detection signal and the position of the operation command becomes equal to or less than the settling range (allowable accuracy).

[0041] The amount of overshoot is the amount of excess movement, and is the maximum value of the error between the command position and the position of the servo motor M1 after the servo motor M1 reaches the target position.

[0042] The position deviation is the deviation between the position of the operation command and the position of the servo motor M1. The performance evaluation value for the position deviation is, for example, one or a combination of the average value, effective value, maximum value, or variance (square root of variance) of the position deviation during operation.

[0043] The performance evaluation value of the torque command is, for example, one or a combination of the average value, effective value, maximum value, or variance (square root of variance) of the torque command or torque command differential value during operation.

[0044] The control margin includes, for example, at least one of a gain margin and a phase margin in the open-loop frequency characteristics of the feedback control system. The gain margin is the value obtained by multiplying the gain value at the phase crossover frequency by -1 in the open-loop frequency characteristics of the feedback control system. The larger the value, the greater the margin is determined to be. Furthermore, the phase margin is the value obtained by adding 180 degrees to the phase value at the gain crossover frequency in the same frequency characteristics, and the larger the value, the greater the margin is determined to be.

[0045] The open-loop characteristics of the feedback control system can be calculated from the frequency characteristics of the motor speed relative to the torque command, the controller structure, and the control parameter values ​​in the controller. Since the controller structure and control parameter values ​​are known in the control device 3, it is possible to calculate the phase margin and gain margin simply by obtaining the frequency characteristics of the motor speed relative to the torque command.

[0046] The device characteristic acquisition unit 14 acquires, from the control device 3, the device characteristics estimated by the control device 3. As described above, the device characteristics are, for example, characteristic values ​​relating to the total inertia value and the friction characteristics.

[0047] The frequency characteristic measurement unit 15 performs a measurement operation in which a torque command containing multiple frequency components is applied as a measurement test signal to the servo motor M1 via the control device 3, and measures time-domain data of the torque command and the speed of the servo motor M1 during this measurement operation. The speed of the servo motor M1, i.e., the motor speed, is obtained by differentiating the motor position acquired by the position detector 5. From the time-domain data of both the torque command and the motor speed during measurement, the frequency characteristic of the motor speed relative to the torque command is calculated. For example, the frequency characteristic measurement unit 15 performs a fast Fourier transform (FFT) on both the time-domain data of the torque command and the motor speed to convert them into frequency-domain data. Then, the frequency characteristic measurement unit 15 calculates the transfer characteristic of the motor speed relative to the torque command for each frequency point (the ratio of the motor speed, which is the output, to the torque command, which is the input signal), and calculates the amplitude ratio as the gain characteristic and the phase ratio as the phase characteristic, respectively, as frequency-domain data.

[0048] Furthermore, the frequency characteristic measurement unit 15 uses, for example, a white noise signal as a type of test signal when measuring frequency characteristics. A white noise signal is a type of random signal that is characterized by uniformly containing multiple frequency components, and is therefore capable of acquiring wideband frequency characteristics in a short period of time. By using this test signal, it is possible to obtain the frequency characteristics of the motor speed in response to a wideband torque command.

[0049] In addition to the function of measuring and calculating the frequency characteristics described above, the frequency characteristic measurement unit 15 also has a function of calculating the resonant frequency and anti-resonant frequency between the servo motor M1 and the load 4 from the measured frequency characteristics. The resonant frequency is the frequency of the convex part of the gain characteristic of the frequency characteristic of the motor speed in response to the measured torque command, and the anti-resonant frequency is the frequency of the concave part. Therefore, the resonant frequency and anti-resonant frequency can be calculated by checking the frequency of the concave and convex parts of the gain characteristic of the measured frequency characteristic.

[0050] The parameter adjustment unit 11 operates the servo motor M1, adjusts the control parameters based on at least the adjustment conditions, and calculates the evaluation index value when the servo motor M1 operates with the control parameters. Specifically, the parameter adjustment unit 11 adjusts the control parameters so as to satisfy the adjustment conditions based on operation information during motor operation obtained by causing the drive system 2 to perform an adjustment operation for adjustment, or operation information during motor operation by the upper controller 6.

[0051] After the parameter adjustment by the parameter adjustment unit 11 is completed, the parameter holding unit 13 stores the control parameters after adjustment in association with the adjustment conditions, the device characteristics and the frequency characteristics of the drive system 2, in addition to the servo data obtained when the servo motor M1 is operated with the control parameters. The servo data includes at least one of the operation command during operation, the motor speed, the command position deviation, and the time domain data of the torque command.

[0052] (2) Operation Fig. 4 is a schematic diagram showing an input screen for control parameters in the adjustment support system 1 according to the embodiment. The operation of the adjustment support system 1 is shown in Fig. 5. That is, Fig. 5 is a flowchart showing the operation of the adjustment support system 1 according to the embodiment. The adjustment support system 1 first determines whether or not to read data (step S1). When setting adjustment conditions for the drive system 2, the adjustment support system 1 accepts a user operation as to whether or not to read previously recorded adjustment result information data.

[0053] If data reading is not to be performed (No in step S1), the adjustment support system 1 performs initial setting (step S2). In the initial setting, the adjustment support system 1 presents the input screen shown in Fig. 4 to the user and accepts input of adjustment conditions for the drive system 2. Step S2 corresponds to the adjustment condition designation step of the present disclosure.

[0054] On the other hand, when data reading is performed (Yes in step S1), the adjustment support system 1 reads out previously recorded combinations of adjustment conditions, device characteristics, frequency characteristics, and control parameters from the parameter storage unit 13 (step S3). At this time, if there are multiple combinations of adjustment conditions, device characteristics, frequency characteristics, and control parameters, the adjustment support system 1 may display information on one or more of the previously read adjustment conditions, device characteristics, and frequency characteristics on the input screen shown in FIG. 4 , and allow the user to select which combination of control parameters to read. Furthermore, the adjustment support system 1 may present the read adjustment conditions, device characteristics, frequency characteristics, and control parameters to the user, and allow the user to input whether to apply the control parameters as they are or to perform fine adjustments. Step S3 corresponds to the adjustment condition designation step of the present disclosure.

[0055] Next, the adjustment support system 1 acquires the device characteristics (step S4). More specifically, the adjustment support system 1 operates the servo motor M1 with the control parameters at that time and estimates parameters related to the inertia ratio and friction characteristics as the device characteristics. Step S4 corresponds to a part of the parameter adjustment step of the present disclosure.

[0056] Next, the adjustment support system 1 measures the frequency characteristics (step S5). More specifically, the adjustment support system 1 performs a measurement operation using a torque command including multiple frequency components, and estimates the frequency characteristics based on the torque command and the speed of the servo motor M1. Step S5 corresponds to the frequency characteristics measurement step of the present disclosure.

[0057] Next, the adjustment support system 1 adjusts the control parameters of the servo motor (step S6). More specifically, the adjustment support system 1 changes at least one of the control parameters, such as the PID control gain and the notch filter. In addition, the adjustment support system 1 calculates the open-loop characteristics of the feedback control system based on the frequency characteristics measured in step S4 and the control parameter values ​​determined in this step, thereby calculating the control margin.

[0058] Next, the adjustment support system 1 measures the evaluation index (step S7). More specifically, the adjustment support system 1 operates the servo motor, acquires time domain data of the servo data at this time, and calculates, based on the acquired time domain data, the positioning settling time or the amount of overshoot, or the position deviation, the average value, effective value, and maximum value of the torque command or torque command differential value, or the variance (square root of variance) of the values ​​during operation.

[0059] Next, the adjustment support system 1 determines the control parameters (step S8). The parameter adjustment unit 11 of the adjustment support system 1 determines the control parameters based on the control margin acquired in step S6, the evaluation index value acquired in step S7, and the adjustment conditions set in step S2 or S3. If the control margin and the evaluation index value satisfy the conditions set in step S2 or S3, the control parameters are determined as the automatic adjustment results, and the process proceeds to the next step. If the control margin and the evaluation index value do not satisfy the conditions set in step S2 or S3, the process returns to step S6 again and changes the control parameter values.

[0060] Step S4 and steps S7 to S9 correspond to the parameter adjustment steps of the present disclosure.

[0061] Next, the adjustment support system 1 stores the control parameter data (step S9). The parameter adjustment unit 11 of the adjustment support system 1 associates the control parameters determined in step S8 with the device characteristics acquired in step S4, the frequency characteristics measured in step S5, and the evaluation index values ​​calculated in step S8, and stores them in the parameter storage unit. Step S9 corresponds to the parameter storage step of the present disclosure.

[0062] (3) Effects The adjustment support method according to the embodiment associates and stores the adjustment conditions for automatic adjustment, device characteristics, frequency characteristics, and adjusted control parameters, as well as servo data and control margins when operating with the control parameters. This allows the user to easily check whether there are any changes in the automatic adjustment settings, device characteristics, or frequency characteristics if the operation of the drive unit changes after adjusting or re-adjusting the control parameters, thereby making it possible to easily grasp the cause.

[0063] In the adjustment support method according to the embodiment, the adjustment conditions include an evaluation index value. The evaluation index value includes at least the positioning settling time, the amount of overshoot, and the average, effective value, or maximum value of the position deviation, torque command, or torque command differential value in parameter adjustment step S8. This makes it possible to reduce the occurrence of problems in the drive system 2 caused by a deterioration in the evaluation index value when the user adjusts the control parameters.

[0064] In the adjustment support method according to the embodiment, the adjustment conditions include a control margin. The control margin includes at least one of a gain margin and a phase margin. This allows the user to easily understand the extent to which the control parameters can be varied when adjusting the control parameters.

[0065] In addition, in the adjustment assistance method according to the embodiment, the device characteristics include at least one of parameters related to inertia and friction characteristics. This allows the user to check the device characteristics that the control parameters are based on when adjusting the control parameters. Therefore, the user can adjust the control parameters based on knowledge of whether the control characteristics are fluctuating.

[0066] Furthermore, in the adjustment assistance method according to the embodiment, a plurality of combinations of control parameters and device characteristics, frequency characteristics, and adjustment conditions associated with the control parameters are stored in the parameter storage step S9. This makes it easy for the user, when adjusting the control parameters, to select and use control parameters suitable for the drive system 2 from a plurality of control parameters associated with different device characteristics, frequency characteristics, and adjustment conditions.

[0067] In the adjustment support method according to the embodiment, the frequency characteristic measuring step S5 calculates a resonant frequency and an anti-resonant frequency based on the frequency characteristic. The parameter storing step S9 further associates the resonant frequency and the anti-resonant frequency with the control parameter and stores them. This makes it easy for the user to adjust the control parameter related to the frequency characteristic when adjusting the control parameter.

[0068] In the adjustment support method according to the embodiment, at least one of a white noise signal and a multi-sine signal is used to measure the frequency characteristics in the frequency characteristic measurement step S5. This allows the torque command for measuring the frequency characteristics to include multiple frequency components, making it possible to measure the frequency components in a short time.

[0069] Furthermore, the program according to the embodiment may be a program that causes one or more processors to execute the adjustment support method according to the embodiment.

[0070] The adjustment support system 1 according to the embodiment is an adjustment support system for a control device 3 that controls a servo motor M1. The adjustment support system 1 includes an adjustment condition designation unit 12, a device characteristic acquisition unit 14, a frequency characteristic measurement unit 15, a parameter adjustment unit 11, and a parameter storage unit 13. The adjustment condition designation unit 12 designates target adjustment conditions for adjusting the servo motor M1. The device characteristic acquisition unit 14 acquires device characteristics of a drive system 2 including the servo motor M1. The frequency characteristic measurement unit 15 measures frequency characteristics of the motor position relative to a position command. The parameter adjustment unit 11 operates the servo motor M1 and adjusts control parameters of a position / speed control unit 30 based on the device characteristics, frequency characteristics, and adjustment conditions to calculate an evaluation index value. The parameter storage unit 13 stores the control parameters in association with the device characteristics, frequency characteristics, and evaluation index value. This allows a user to adjust the control parameters by referring to the device characteristics, frequency characteristics, and evaluation index value. Therefore, if a change occurs in the operation of the servo motor after adjustment of the control device, the user can accurately and easily grasp the cause of the change.

[0071] (4) Modifications Modifications of the above embodiment are listed below. The modifications described below can be applied in appropriate combinations.

[0072] The same functions as those of the adjustment support system 1 according to the above embodiment may be embodied in an adjustment support method, a computer program, or a non-transitory recording medium on which a computer program is recorded.

[0073] The adjustment support system 1 in the present disclosure includes a computer system. The computer system is primarily composed of a processor and memory as hardware. The processor executes a program stored in the memory of the computer system to realize the functions of the adjustment support system 1 in the present disclosure. The program may be pre-recorded in the memory of the computer system, provided via a telecommunications line, or provided in a non-transitory recording medium readable by the computer system, such as a memory card, optical disk, or hard disk drive. The processor of the computer system is composed of one or more electronic circuits including a semiconductor integrated circuit (IC) or a large-scale integrated circuit (LSI). The integrated circuits, such as ICs or LSIs, are referred to by different names depending on the degree of integration, and include integrated circuits called system LSIs, very large-scale integrations (VLSIs), or ultra-large-scale integrations (ULSIs). Furthermore, field-programmable gate arrays (FPGAs), which are programmed after the LSI is manufactured, or logic devices capable of reconfiguring the connections within the LSI or the circuit partitions within the LSI, can also be used as processors. The electronic circuits may be integrated into one chip or distributed across multiple chips. The chips may be integrated into one device or distributed across multiple devices. The computer system referred to here includes a microcontroller having one or more processors and one or more memories. Therefore, the microcontroller is also composed of one or more electronic circuits including a semiconductor integrated circuit or a large-scale integrated circuit.

[0074] Furthermore, it is not essential that the multiple functions of the adjustment support system 1 are concentrated in one housing. For example, the components of the adjustment support system 1 may be distributed across multiple housings.

[0075] Conversely, multiple functions of the adjustment support system 1 may be integrated into one housing. Furthermore, at least some of the functions of the adjustment support system 1, for example, some of the functions of the adjustment support system 1, may be realized by the cloud (cloud computing) or the like.

[0076] Also, (1) in the above embodiment, the relationship between the operating position when measuring the frequency characteristics and the operating position when adjusting the servo motor M1 while moving it was not clearly stated, but it is also possible to configure the servo motor M1 to be moved during adjustment within a range that includes the operating position when measuring the frequency characteristics. This allows the frequency characteristics to be measured at the operating position during adjustment or a position close to this, and by maintaining the frequency characteristics at the motor operating position during adjustment, it becomes possible to accurately grasp and analyze the relationship between the two.

[0077] In addition, (2) in the above embodiment, various data are stored in a parameter storage unit, and when data is read in step S2, the data is read from the storage unit. However, instead of the parameter storage unit, various data may be stored in the same file. By adopting such a configuration, even if the data in the storage unit is erased, it is possible to check past data.

[0078] Furthermore, (3) in the above embodiment, it is also possible to configure the parameter storage unit to store multiple data sets and simultaneously display the multiple data sets on the display unit. This configuration allows the user to easily compare multiple past adjustment results, making it easy to determine whether there is a difference in motor operation after adjustment, and if there is a difference, what the cause is.

[0079] Also, (4) In the above embodiment, the adjustment support system 1 performs the processes in the order of acquiring device characteristics, measuring frequency characteristics, and adjusting control parameters. However, this order may be reversed. For example, a configuration may be adopted in which the frequency characteristics are measured first, then the servo motor M1 is operated to acquire device characteristics, and finally the servo motor M1 is operated in the same manner to adjust the control parameters. Alternatively, the frequency characteristics may be measured first, then the servo motor M1 is operated to adjust the control parameters, and device characteristics may be estimated based on the operation during adjustment. Alternatively, the frequency characteristics may be measured first, then the servo motor M1 is operated to adjust the control parameters, and finally the servo motor M1 is operated to estimate the device characteristics. Either configuration may achieve the same effects as the above embodiment.

[0080] Furthermore, (5) in the above embodiment, the data recording in the adjustment support system 1 (step S9) is configured to record the servo data and evaluation index values ​​when the motor is operated with the adjusted control parameters determined in step S8 in association with the control parameters. However, the servo data and evaluation index values ​​for all control parameters tried in steps S6 and S7 may also be associated and recorded as an adjustment history. One possible solution to a difference in operation compared to previous adjustment results is to re-adjust the control parameters to reduce the difference between the operation or performance index value and the previous adjustment results. This configuration allows all servo data and evaluation index values ​​for each control parameter confirmed during parameter re-adjustment to be tracked. Therefore, if there are differences in operation or evaluation index values ​​compared to previous adjustment results, it is possible to confirm, for example, the control parameter conditions with the smallest difference without having to operate the motor again. This allows the user to select control parameters that minimize the difference from the operation or evaluation index value at the time of previous adjustment when re-adjusting the control parameters, thereby reducing the time required for the user to select the control parameters that minimize the difference from the operation or evaluation index value at the time of previous adjustment.

[0081] (Summary) An adjustment support method according to a first aspect is an adjustment support method for a control device (3) that controls a servo motor (M1). The control device (3) includes a feedback control unit (30) that provides the servo motor (M1) with a torque command to reduce a difference between a position command and the motor position. The adjustment support method includes an adjustment condition designation step (S2, S3), a device characteristic acquisition step (S4), a frequency characteristic measurement step (S5), a parameter adjustment step (S8), and a parameter retention step (S9).

[0082] In the adjustment condition specification steps (S2, S3), target adjustment conditions are specified for adjusting the servo motor (M1). In the device characteristic acquisition step (S4), device characteristics of the device (2) including the servo motor (M1) are acquired. In the frequency characteristic measurement step (S5), frequency characteristics of the motor position relative to a position command are measured. In the parameter adjustment step (S8), the servo motor (M1) is operated, and control parameters of the feedback control unit (30) are adjusted based on the device characteristics, frequency characteristics, and adjustment conditions to calculate an evaluation index value. In the parameter storage step (S9), the control parameters are stored in association with the device characteristics, frequency characteristics, and evaluation index value.

[0083] According to the adjustment support method of the above aspect, when adjusting control parameters, the user can refer to the device characteristics, frequency characteristics, and evaluation index values ​​to make decisions, thereby enabling the user to easily apply more appropriate control parameters.

[0084] In the adjustment support method according to the second aspect, in the first aspect, the adjustment conditions include an evaluation index value, which includes at least the positioning settling time, the amount of overshoot, and the average value, effective value, or maximum value of the position deviation, the torque command, or the torque command differential value in the parameter adjustment step (S8).

[0085] According to the adjustment assistance method of the above aspect, it is possible to reduce the occurrence of problems in the drive system 2 caused by a deterioration in the evaluation index value when the user adjusts the control parameters.

[0086] In an adjustment support method according to a third aspect, in the first or second aspect, the adjustment conditions include a control margin, and the control margin includes at least one of a gain margin and a phase margin.

[0087] According to the adjustment support method of the above aspect, when the user adjusts a control parameter, the user can easily grasp the extent to which the control parameter can be varied.

[0088] In an adjustment assistance method according to a fourth aspect, in any one of the first to third aspects, the device characteristics include at least one of parameters relating to inertia and friction characteristics.

[0089] According to the adjustment support method of the above aspect, when a user adjusts a control parameter, the user can check the device characteristics on which the control parameter is based, and can adjust the control parameter based on the knowledge of whether the control characteristic has fluctuated.

[0090] In the adjustment support method according to the fifth aspect, in any of the first to fourth aspects, the parameter storage step (S9) stores a plurality of combinations of control parameters and device characteristics, frequency characteristics, and adjustment conditions associated with the control parameters.

[0091] According to the adjustment support method of the above aspect, when a user adjusts a control parameter, it becomes easy for the user to select and use a control parameter suitable for the device (2) from a plurality of control parameters that are associated with different device characteristics, frequency characteristics, and adjustment conditions.

[0092] In the adjustment support method according to a sixth aspect, in any of the first to fifth aspects, the frequency characteristic measuring step (S5) calculates a resonant frequency and an anti-resonant frequency based on the frequency characteristic, and the parameter storing step (S9) further associates the resonant frequency and the anti-resonant frequency with a control parameter and stores them.

[0093] According to the adjustment support method according to the above aspect, when the user adjusts the control parameters, it becomes easy for the user to adjust the control parameters relating to the frequency characteristics.

[0094] In an adjustment support method according to a seventh aspect, in any of the first to sixth aspects, in the frequency characteristic measuring step (S5), at least one of a white noise signal and a multisine signal is used to measure the frequency characteristic.

[0095] According to the adjustment assistance method of the above aspect, since the torque command for measuring the frequency characteristics includes a plurality of frequency components, it is possible to measure the frequency components in a short time.

[0096] In the adjustment support method according to an eighth aspect, in any of the first to seventh aspects, the parameter storing step (S9) further stores the adjustment history in the parameter adjusting step (S8) in association with the control parameters.

[0097] According to the adjustment support method of the above aspect, when the user adjusts the control parameters, the user can refer to the adjustment history of the control parameters, which further facilitates the user's task of optimizing the control parameters.

[0098] A program according to a ninth aspect causes one or more processors to execute the adjustment support method according to any one of the first to eighth aspects.

[0099] According to the program of the above aspect, the user can refer to the device characteristics, frequency characteristics, and evaluation index values ​​when adjusting the control parameters, thereby enabling the user to easily apply more appropriate control parameters.

[0100] An adjustment support system (1) according to a tenth aspect is an adjustment support system for a control device (3) that controls a servo motor (M1). The control device (3) includes a feedback control unit (30) that provides the servo motor (M1) with a torque command to reduce the difference between a position command and the motor position. The adjustment support system (1) includes an adjustment condition designation unit (12), a device characteristics acquisition unit (14), a frequency characteristics measurement unit (15), a parameter adjustment unit (11), and a parameter storage unit (13). The adjustment condition designation unit (12) designates target adjustment conditions for adjusting the servo motor (M1). The device characteristics acquisition unit (14) acquires device characteristics of a device (2) that includes the servo motor (M1). The frequency characteristics measurement unit (15) measures the frequency characteristics of the motor position relative to the position command. The parameter adjustment unit (11) operates the servo motor (M1) and adjusts control parameters of the feedback control unit (30) based on the device characteristics, frequency characteristics, and adjustment conditions to calculate an evaluation index value. A parameter storage unit (13) stores control parameters in association with device characteristics, frequency characteristics, and evaluation index values.

[0101] According to the adjustment support system (1) of the above aspect, when adjusting control parameters, the user can refer to the device characteristics, frequency characteristics, and evaluation index values ​​to make a decision, thereby enabling the user to easily apply more appropriate control parameters.

[0102] The adjustment support method, program, and adjustment support system disclosed herein enable a user to accurately and easily identify the cause of a change in servo motor operation after adjustment of a control device. Thus, the adjustment support method, program, and adjustment support system disclosed herein are industrially useful.

[0103] REFERENCE SIGNS LIST 1 Adjustment support system 11 Parameter adjustment unit 12 Adjustment condition designation unit 13 Parameter storage unit 14 Device characteristic acquisition unit 15 Frequency characteristic measurement unit M1 Servo motor 2 Drive system (device) 3 Control device 30 Position / speed control unit (feedback control unit) S2, S3 Adjustment condition designation step S4 Device characteristic acquisition step S5 Frequency characteristic measurement step S8 Parameter adjustment step S9 Parameter storage step

Claims

1. A method for supporting adjustment of a control device that controls a servo motor, wherein the control device comprises a feedback control unit that provides the servo motor with a torque command to reduce a difference between a position command and a motor position, the adjustment support method comprising: an adjustment condition designation step that designates target adjustment conditions in adjusting the servo motor; a frequency characteristic measurement step that measures the frequency characteristic of the motor speed with respect to the torque command; a parameter adjustment step that operates the servo motor, estimates the device characteristics, adjusts control parameters of the feedback control unit based on the adjustment conditions, and calculates an evaluation index value for motor operation during operation; and a parameter storage step that, after the parameter adjustment, stores the adjusted control parameters in association with the device characteristics, the frequency characteristics, and the evaluation index value.

2. The adjustment support method according to claim 1, wherein the measurement of the frequency characteristics is performed within the operating range of the motor.

3. The adjustment support method according to claim 1, wherein the saving step further saves time domain data of at least one of the command pattern, motor speed, torque command, and position deviation between the command pattern and motor position when operating with the control parameters.

4. The adjustment support method according to claim 1, wherein the adjustment conditions include the evaluation index value, and the evaluation index value includes at least one of the positioning settling time, the amount of overshoot, and the position deviation, the average value, the effective value, and the maximum value of the torque command or the torque command differential value in the parameter adjustment step.

5. The adjustment support method according to claim 1, wherein the adjustment conditions include a control margin, and the control margin includes at least one of a gain margin and a phase margin.

6. The adjustment assistance method according to claim 1, wherein the device characteristics include at least one of parameters relating to inertia and friction characteristics.

7. The adjustment support method according to claim 1, wherein the saving step stores a plurality of combinations of the control parameters and the device characteristics, the frequency characteristics, and the adjustment conditions associated with the control parameters.

8. The adjustment support method according to claim 1, wherein in the frequency characteristic measuring step, a resonant frequency and an anti-resonant frequency are calculated based on the frequency characteristic, and in the parameter storing step, the resonant frequency and the anti-resonant frequency are further stored in association with the control parameters.

9. The adjustment support method according to claim 1, wherein the parameter holding step further stores the control parameters of the operations performed during adjustment and the evaluation index values ​​in association with each other as an adjustment history in the parameter adjustment step.

10. A program for causing one or more processors to execute the adjustment support method according to any one of claims 1 to 8.

11. An adjustment support system for a control device that controls a servo motor, wherein the control device comprises a feedback control unit that gives the servo motor a torque command to reduce the difference between a position command and a motor position, the adjustment support system specifying target adjustment conditions in adjusting the servo motor, measuring the frequency characteristics of the motor speed with respect to the torque command, operating the servo motor, estimating the device characteristics, adjusting control parameters of the feedback control unit based on the adjustment conditions, and calculating an evaluation index value for motor operation during operation, and after the parameter adjustment, retaining the adjusted control parameters in association with the device characteristics, the frequency characteristics, and the evaluation index value.

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