Control parameter generation method, control parameter generation program and storage medium

Abstract

To provide a control parameter generation method capable of calculating control parameters for controlling a motor of a conveying device at a low load, and also to provide a control parameter generation program and a storage medium.SOLUTION: A sweep sine wave signal is input to a Y motor that moves a retention mechanism. An actual measurement value of motor speed of the Y motor is acquired by an encoder. An estimation value of the speed of the Y motor is acquired based on a mathematical model. Inertia of the Y motor is calculated by the sequential least squares method so that difference between the actual measurement value and the estimation value of the motor speed becomes small (S12). Mass of the retention mechanism is acquired by applying calculated inertia to previously prepared approximate expression of relationship between the mass and the inertia (S13). Control gain is calculated based on speed closed-loop transfer function (S17) and set as a control parameter (S19).SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a control parameter generation method, a control parameter generation program, and a storage medium for controlling a motor of a conveyance device. [Background technology]

[0002] Patent Document 1 discloses a mechanized model for motor control, including the machine's drive mechanism. The command generator in Patent Document 1 creates a swept sine wave signal and sends it to a current controller to operate the motor. A detector detects the motor operation amount, which includes information on the machine's operation amount, and sends it to a signal processor as a response signal. The response signal has resonance characteristics that depend on the machine's frequency. The signal processor detects the time and amplitude at which the absolute value of the response signal is maximum, and detects the machine's resonance frequency based on the relationship between the time and frequency of the swept sine wave signal. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-348871 Summary of the Invention [Problem to be solved by the invention]

[0004] In Patent Document 1, all frequencies of a swept sine wave signal are input to a current controller, and response signals for all time periods in a time series of motor operating amounts that operate in response to the input signals are acquired and graphed, and the maximum and minimum values ​​are identified to calculate the resonant frequency of the machine. This poses problems such as a large memory capacity being required to store the response signals for all time periods in the time series, and a computational load being imposed to query all data of the response signals and detect the resonant frequency.

[0005] An object of the present invention is to provide a control parameter generation method, a control parameter generation program, and a storage medium that can calculate control parameters for controlling a motor of a conveyance device with a low load. [Means for solving the problem]

[0006] According to a first aspect of the present invention, in a transport device that transports an object to be transported, the transport device includes a motor, a motor control device that controls the motor, and a transmission mechanism that transmits power generated by the motor to the object to be transported. The control parameter generation method generates control parameters used by the motor control device in accordance with the mass of the object to be transported, the control parameter generation method including a time characteristic acquisition step of inputting a sweep signal having a time characteristic in which the frequency of a signal value changes over time to the motor, and acquiring a characteristic of the motor speed of the motor versus elapsed time, a speed processing step of calculating a processing speed by converting the acquired motor speed into an absolute value and applying a low-pass filter, and a predetermined waiting time from the start of input of the sweep signal. The present invention provides a control parameter generation method comprising: a minimum value acquisition step of calculating the minimum value of the processing speed of the motor speed for each elapsed time acquired after the machine time has elapsed, and acquiring a first time when the minimum value first reached a minimum value and the minimum value; an inertia calculation step of calculating the inertia of the motor based on the motor speed acquired during the period from the elapse of the waiting time to the first time when the minimum value was acquired and a mathematical model; a mass calculation step of calculating the mass of the transport object based on the calculated inertia and an approximation equation; and a parameter calculation step of calculating the control parameter based on the calculated mass of the transport object.

[0007] In the control parameter generation method, the characteristics of the motor speed versus elapsed time are sequentially acquired, and the machining speed is sequentially calculated by converting the motor speed into an absolute value and applying a low-pass filter. This makes it possible to calculate a minimum value from the machining speed, and the inertia of the motor is calculated based on the motor speed up to the first time when the first minimum value was obtained. The mass of the transport object is then calculated from the inertia, thereby calculating the motor control parameters. In this way, the control parameter generation method requires less memory capacity and less computational load than when the characteristics of the motor speed versus elapsed time are acquired over an entire period and, after acquisition is complete, parameters are calculated based on all the characteristics over that period, and therefore can be implemented with inexpensive hardware.

[0008] In the first aspect, the inertia calculation step may calculate the inertia using a recursive least squares method so as to minimize the difference between the motor speed and a motor speed estimate previously obtained from the mathematical model. By calculating the inertia using the recursive least squares method each time, the control parameter generation method requires less memory capacity and a smaller calculation load than when calculating the inertia from scratch using the motor speeds up to that point each time a motor speed is obtained, and therefore can be realized with inexpensive hardware.

[0009] In a first aspect, the control parameter generation method may further include a mass presentation step of presenting the mass of the object to be transported calculated in the mass calculation step, and a judgment input step of receiving input of a judgment as to whether the presented mass is appropriate, and if a judgment that the mass is inappropriate is input, calculation of the control parameters by the parameter calculation step may be stopped. By having a user judge whether the mass calculation result is appropriate, if a mass that is significantly different from the mass of the object to be transported due to, for example, a disturbance, etc. is calculated, calculation of the control parameters based on that mass can be stopped, and it is possible to prevent the motor from being controlled with inappropriate parameters.

[0010] In a first aspect, the method may further include a resonance frequency acquisition step of calculating, based on the time characteristics of the sweep signal, a frequency input to the motor at the first time when the machining speed reaches the minimum value, and acquiring the frequency as the resonance frequency of the object to be transported, and the parameter calculation step may calculate the control parameter based on the calculated resonance frequency of the object to be transported and the mass. It is known in advance that the calculated resonance frequency of the object to be transported corresponds to an anti-resonance frequency of the motor. Therefore, in the control parameter generation method, for example, by calculating the control parameter so that the gain characteristic of a closed loop of the motor speed attenuates at the resonance frequency of the object to be transported, it is possible to suppress resonance of the object to be transported and control the motor so that the object can be transported stably.

[0011] In a first aspect, the control parameter generation method further includes a maximum value acquisition step of calculating a maximum value of the machining speed of the motor speed for each elapsed time acquired after the waiting time has elapsed since the start of input of the sweep signal, and acquiring a second time when the maximum value first reaches a maximum value and the maximum value, and a motor resonant frequency acquisition step of calculating a frequency input to the motor at the second time when the machining speed reaches the maximum value based on the time characteristic of the sweep signal, and acquiring the frequency as the resonant frequency of the motor, wherein the parameter calculation step may calculate the control parameter based on the calculated resonant frequency of the object to be conveyed, the resonant frequency of the motor, and the mass. In the control parameter generation method, for example, by calculating the control parameter such that a gain characteristic of a closed loop of the motor speed attenuates at the resonant frequency of the object to be conveyed and the resonant frequency of the motor, it is possible to suppress resonance of the object to be conveyed and control the motor so that the object to be conveyed is stably conveyed.

[0012] In a first aspect, the minimum value acquisition step may successively calculate the minimum value of the machining speed of the motor speed, update the smallest value, and set the value that is not updated beyond a predetermined first time as the minimum value. In the control parameter generation method, the minimum value can be acquired based on the successively calculated minimum value of the machining speed. Therefore, compared to acquiring the characteristics of the motor speed and elapsed time over an entire period, calculating the machining speed after acquisition is completed, the memory capacity used and the calculation load are smaller, and therefore the method can be realized with inexpensive hardware.

[0013] In a first aspect, the control parameter generation method may further include a maximum value acquisition step of sequentially calculating the minimum value of the machining speed of the motor speed, updating the minimum value, and setting the value that is not updated for more than a predetermined first time as the minimum value, and a maximum value acquisition step of sequentially calculating the maximum value of the machining speed of the motor speed, updating the maximum value, and setting the value that is not updated for more than a predetermined second time as the maximum value, and a maximum value initialization step of initializing the maximum value when the first time has elapsed since the first time, and a minimum value initialization step of initializing the minimum value when the second time has elapsed since the second time. Since the control parameter generation method can acquire the minimum value and the maximum value based on the sequentially calculated minimum and maximum values ​​of the machining speed, the method requires less memory capacity and requires less computational load than a method of acquiring a characteristic of the motor speed versus elapsed time over an entire period, calculating the machining speed after the acquisition is complete, and then calculating the minimum value, and thus can be implemented with inexpensive hardware.

[0014] In a first aspect, the transport device may be used in a sewing machine, the transport target may be a holding mechanism that holds a sewing workpiece, the transmission mechanism may be a feed mechanism that moves the holding mechanism relative to a needle bar mechanism that drives a needle bar, and the motor may be a motor that drives the feed mechanism. By controlling the motor using the control parameters generated by the control parameter generation method, the sewing machine can suppress resonance of a support frame to which the sewing workpiece is fixed and stably transport the support frame.

[0015] According to a second aspect of the present invention, in a transport device that includes a motor, a motor control device that controls the motor, and a transmission mechanism that transmits power generated by the motor to a transport object, and that transports the transport object, there is provided a control parameter generation program that generates control parameters used by the motor control device in accordance with the mass of the transport object, the control parameter generation program including a time characteristic acquisition step of inputting a sweep signal having a time characteristic in which the frequency of a signal value changes over time to the motor, and acquiring a characteristic of the motor speed of the motor versus elapsed time, a speed processing step of calculating a processing speed by converting the acquired motor speed into an absolute value and applying a low-pass filter, and a time characteristic acquisition step of inputting a sweep signal having a time characteristic in which the frequency of a signal value changes over time to the motor ... acquiring a characteristic of the motor speed versus elapsed time, and a time characteristic acquisition step of inputting a sweep signal having a time characteristic in which the frequency of a signal value changes over time to the motor, and a minimum value acquisition step of calculating a minimum value of the machining speed of the motor speed for each elapsed time acquired after a predetermined waiting time has elapsed from the elapse of the waiting time, and acquiring a first time when the minimum value first becomes a minimum value and the minimum value, an inertia calculation step of calculating an inertia of the motor based on the motor speeds acquired during the period from the elapse of the waiting time to the first time when the minimum value was acquired and a mathematical model, a mass calculation step of calculating the mass of the transport object based on the calculated inertia and an approximation equation, and a parameter calculation step of calculating the control parameter based on the calculated mass of the transport object.

[0016] According to a third aspect of the present invention, in a transport device for transporting the object, the transport device includes a motor, a motor control device for controlling the motor, and a transmission mechanism for transmitting power generated by the motor to the object to be transported. In order to generate control parameters used by the motor control device according to the mass of the object to be transported, a computer of the transport device includes a time characteristic acquisition step of inputting a sweep signal having a time characteristic in which the frequency of a signal value changes over time to the motor to acquire a characteristic of the motor speed and elapsed time of the motor, a speed processing step of calculating a processing speed by converting the acquired motor speed into an absolute value and applying a low-pass filter, and a predetermined waiting time from the start of input of the sweep signal. a minimum value acquisition step of calculating a minimum value of the machining speed of the motor speed for each elapsed time acquired after the waiting time has elapsed and acquiring a first time when the minimum value first becomes a minimum value and the minimum value, an inertia calculation step of calculating an inertia of the motor based on the motor speed acquired during the period from the elapse of the waiting time until the first time when the minimum value was acquired and a mathematical model, a mass calculation step of calculating the mass of the object to be conveyed based on the calculated inertia and an approximation equation, and a parameter calculation step of calculating the control parameter based on the calculated mass of the object to be conveyed. [Brief explanation of the drawings]

[0017] [Figure 1] FIG. 1 is a perspective view of a sewing machine 1. [Figure 2] 2 is a block diagram showing the electrical configuration of the sewing machine 1. FIG. [Figure 3] 1 shows a servo control system of the drive circuit 43. [Figure 4] FIG. 10 is a diagram illustrating a flow of generating control parameters. [Figure 5] 10 is a continuation of the diagram for explaining the flow of generating control parameters. [Figure 6] 10 is a flowchart of a control parameter generation process. [Figure 7]10 is a flowchart of an inertia and resonance frequency calculation process. [Figure 8] 10 is a flowchart of an inertia number calculation process. [Figure 9] 10 is a flowchart of a resonance frequency calculation process. [Figure 10] 10 is a flowchart of a modified example of the resonant frequency calculation process. [Figure 11] 10 is a continuation of the flowchart of the modified example of the resonant frequency calculation process. DETAILED DESCRIPTION OF THE INVENTION

[0018] The following description will be given of specific embodiments of the present invention with reference to the drawings. The drawings are used to explain the technical features that the present invention can employ, and the configurations of the devices described are merely illustrative examples and are not intended to limit the scope of the present invention. In the following description, arrows in the drawings will be used to indicate left and right, front and back, and up and down.

[0019] The sewing machine 1 shown in Figure 1 is an example of a conveying device that generates control parameters using the control parameter generation method of the present invention and conveys an object by controlling the drive of a motor using the control parameters. The sewing machine 1 is a gate-type sewing machine that can sew on a sewing object. The sewing machine 1 has a bed 2, a pair of pillars 3 and 4, a synchronization mechanism 31 (see Figure 2), a conveying mechanism 9 (see Figure 2), a holding mechanism 8, a beam 5, a needle bar mechanism 6, a shuttle mechanism 7, a feed mechanism 10 (see Figure 2), and an operation unit 15.

[0020] The bed 2 has a base 21, a pair of front and rear rails, a frame 22, and a pair of lower rails. The base 21 is generally rectangular. The upper surface of the base 21 forms a flat, horizontally extending holding surface 21A. A holding plate 23 extending forward along the holding surface 21A is provided at the front end of the base 21. A bellows 21R extending in the front-rear direction is provided near the right end of the holding surface 21A. A bellows 21L extending in the front-rear direction is provided near the left end of the holding surface 21A. The pair of front and rear rails are provided below the bellows 21L, 21R. The pair of front and rear rails support a holding mechanism 8 (described below) so that it can move in the front-rear direction. The bellows 21R, 21L expand and contract in response to the reciprocating movement of the holding mechanism 8 in the front-rear direction. The frame 22 is a lattice-like structure that supports the base 21 from below. The pair of lower rails extend in the left-right direction below the base 21. The pair of lower rails support a shuttle mechanism 7 (described later) so that the shuttle mechanism 7 can move left and right. The bed 2 has a lower belt, a lower spline shaft, and the shuttle mechanism 7 (described later) disposed below the base 21.

[0021] The pair of pillars 3, 4 are each shaped like a substantially rectangular pillar. The pillar 3 extends upward from a position at the right end of the base 21 of the bed 2 and forward of the center in the front-to-rear direction. The pillar 3 is located to the right of the bellows 21R in the left-to-right direction. The pillar 4 extends upward from a position at the left end of the base 21 of the bed 2 and forward of the center in the front-to-rear direction. The pillar 4 is located to the left of the bellows 21L in the left-to-right direction. The pillars 3, 4 are spaced apart in the left-to-right direction.

[0022] The synchronization mechanism 31 (see Figure 2) synchronizes the needle bar mechanism 6 and the shuttle mechanism 7 and includes a main motor 32 (see Figure 2), an upper spline shaft, a lower spline shaft, and a transmission mechanism. The main motor 32 is supported by the pillar 3. The upper and lower spline shafts extend in the left-right direction between the pillars 3 and 4. The transmission mechanism of the synchronization mechanism 31 is housed in the pillar 3 and transmits the power of the main motor 32 to the upper and lower spline shafts. The feed mechanism 9 (see Figure 2) can move the shuttle mechanism 7 and the needle bar mechanism 6 in the left-right direction parallel to the horizontal direction relative to the holding mechanism 8 that holds the sewing workpiece, and includes an X-motor 95 (see Figure 2), an upper belt, a lower belt, and a transmission mechanism. The X-motor 95 is a servo motor and is supported by the pillar 4. The transmission mechanism of the feed mechanism 9 is housed in the pillar 4 and transmits the power of the X-motor 95 to the upper and lower belts. The upper belt is fixed to the rear surface of the needle bar mechanism 6. The lower belt is fixed to the rear surface of the shuttle mechanism 7. The shuttle mechanism 7 and the needle bar mechanism 6 move left and right in response to the rotation of the X motor 95.

[0023] The beam 5 is installed between the pillars 3 and 4. The beam 5 extends in the left-right direction between the pair of pillars 3 and 4. The beam 5 has a housing 51. The housing 51 extends between the upper and rear ends of the pillars 3 and 4. A pair of upper rails is provided in the space surrounded by the pillars 3 and 4 and the housing 51. The upper rails are rod-shaped and installed between the pillars 3 and 4. The upper rails support the needle bar mechanism 6 so that it can move left and right. The bellows 52 is installed at the front ends of the pillars 3 and 4 and the housing 51, and across both the left and right ends of the needle bar mechanism 6. The bellows 52 covers the front side of the upper rails, upper belt, and upper spline shaft. The bellows 52 expands and contracts as the needle bar mechanism 6 moves back and forth left and right along the upper rails.

[0024] The needle bar mechanism 6 is located on the front side of the beam 5. The needle bar mechanism 6 includes a needle bar 61, a presser foot 62, a thread take-up mechanism 63, a thread tensioner 64, and an upper shaft. The needle bar 61 extends vertically and can have a sewing needle attached to its lower end. The needle bar 61 is movable vertically. The presser foot 62 has a through-hole through which the sewing needle passes as the needle bar 61 moves, and presses down on the workpiece from above. The thread take-up mechanism 63 operates in response to the vertical movement of the needle bar 61 to pull up the upper thread. The thread tensioner 64 adjusts the tension of the upper thread. The back of the needle bar mechanism 6 is connected to the upper belt. An upper rail within the beam 5 supports the needle bar mechanism 6 so that it can move laterally. Therefore, the needle bar mechanism 6 can move laterally along the front end of the beam 5. The upper shaft extends horizontally within the needle bar mechanism 6. The transmission mechanism of the synchronization mechanism 31 transmits power from the upper spline shaft to the upper shaft. The needle bar 61 extends vertically, is connected to the upper shaft, and is driven by the main motor 32 to move up and down.

[0025] The shuttle mechanism 7 is located below the needle bar mechanism 6 and inside the bed portion 2. The shuttle mechanism 7 comprises a lower shaft, a shuttle, and a transmission mechanism. The housing is box-shaped and has a needle plate at the upper left end. The needle plate has a needle hole through which a sewing needle can be inserted. The needle hole is located below the needle bar 61. The back of the shuttle mechanism 7 is connected to the lower belt. A lower spline shaft passes through the shuttle mechanism 7. The shuttle mechanism 7 is supported by a lower rail. Driven by the transport mechanism 9, the shuttle mechanism 7 moves left and right along the lower rail in sync with the needle bar mechanism 6. The transmission mechanism of the shuttle mechanism 7 transmits the power of the lower spline shaft to the lower shaft. The shuttle is connected to the lower shaft and rotates in sync with the up and down movement of the needle bar 61 in sync with the drive of the main motor 32.

[0026] The feed mechanism 10 (see FIG. 2) is provided below the holding plate 23 with a Y motor 96 (see FIG. 2), connecting portions 11 and 12, a transmission mechanism, and a pair of belts. The Y motor 96 is a servo motor. The lower left end of the connecting portion 11 is disposed on the front-rear rail on the left side of the bed 2. The lower right end of the connecting portion 12 is disposed on the front-rear rail on the right side of the bed 2. The connecting portions 11 and 12 are connected to the holding mechanism 8. The holding mechanism 8 can hold the sewing workpiece. The transmission mechanism of the feed mechanism 10 transmits the power of the Y motor 96 to a pair of belts fixed to the connecting portions 11 and 12. The holding mechanism 8 moves along the pair of front-rear rails of the bed 2 in response to the rotation of the Y motor 96, moving back and forth relative to the needle bar mechanism 6 and the shuttle mechanism 7. The holding mechanism 8 has an upper frame 81, a lower frame 82, and air cylinders 83 and 84. The upper frame 81 and the lower frame 82 are rectangular frames in a plan view and sandwich the sewing workpiece between them. The upper frame 81 opens and closes up and down relative to the lower frame 82 using air cylinders 83 and 84 as drive sources.

[0027] The operation unit 15 is supported at the left end of the base 21. The operation unit 15 includes a switch group 13 and a display unit 14. The switch group 13 is used by an operator to input various instructions. The display unit 14 is a liquid crystal display that can display various images.

[0028] The electrical configuration of the sewing machine 1 will be described with reference to FIG. 2. The control unit 25 of the sewing machine 1 has a CPU 16, a ROM 17, a RAM 18, a storage device 19, an input / output interface (I / O) 20, and drive circuits 41 to 45. The CPU 16 controls the overall operation of the sewing machine 1. The ROM 17 stores programs and the like for executing various processes in advance. The RAM 18 temporarily stores various information generated during the execution of various processes. The storage device 19 is non-volatile and stores various setting values. The storage device 19 stores a program for executing a control parameter generation process. This program is provided by a storage medium such as a DVD-ROM or flash memory, and is installed in the storage device 19 after being connected to the sewing machine 1 via a reader connected via an external interface (not shown).

[0029] Drive circuits 41-45, encoders 56-58, and switch group 13 are connected to I / O 20. Drive circuit 41 is connected to main motor 32 of synchronization mechanism 31, and drives main motor 32 in response to control commands from CPU 16. Drive circuit 42 is connected to X motor 95 of transport mechanism 9, and drives X motor 95 in response to control commands from CPU 16. Drive circuit 43 is connected to Y motor 96 of feed mechanism 10, and drives Y motor 96 in response to control commands from CPU 16. Drive circuit 44 is connected to air cylinders 83 and 84 of holding mechanism 8, and drives air cylinders 83 and 84 in response to control commands from CPU 16. Drive circuit 45 is connected to display unit 14, and displays various information on display unit 14 in response to control commands from CPU 16.

[0030] Encoder 56 detects the rotational position and rotational speed of the output shaft of main motor 32 and inputs the detection results to I / O 20. The detection results of encoder 56 indicate the up-down positions of needle bar 61 and the sewing needle. Encoder 57 detects the rotational direction, rotational position and rotational speed of the output shaft of X motor 95 and inputs the detection results to I / O 20. The detection results of encoder 57 indicate the left-right positions of needle bar mechanism 6 and shuttle mechanism 7. Encoder 58 detects the rotational direction, rotational position and rotational speed of the output shaft of Y motor 96 and inputs the detection results to I / O 20. The detection results of encoder 58 indicate the front-rear position of holding mechanism 8. Switch group 13 detects various instructions and inputs the detection results to I / O 20.

[0031] The control parameter generation method according to the present invention is used, for example, to generate control parameters for controlling the drive of the Y motor 96 of the feed mechanism 10, which moves the holding mechanism 8 that holds the sewing workpiece in the forward and backward directions. The drive circuit 43 that controls the drive of the Y motor 96 constitutes a servo control system. By setting a speed integral gain and a speed proportional gain as control parameters, the drive circuit 43 attenuates the gain characteristics of the speed closed-loop transfer function at the resonance frequency of the holding mechanism 8, thereby suppressing vibration of the holding mechanism 8.

[0032] The servo control system of the drive circuit 43 will be described with reference to Figure 3. The encoder 58 of the Y motor 96 outputs current position information of the Y motor 96 as a position feedback signal to the adder 72. The CPU 16 of the sewing machine 1 generates a position command in accordance with the sewing program to move the holding mechanism 8 in the forward and backward directions when sewing the sewing object, and outputs the command to the drive circuit 43. The drive circuit 43 controls the command current output to the Y motor 96 in accordance with the position command so that the Y motor 96 operates.

[0033] An adder 72 in the drive circuit 43 calculates the position deviation between the position command and the position feedback signal and multiplies the position deviation by a position proportional gain to calculate a velocity command. An adder 73 calculates a velocity deviation between the calculated velocity command, the velocity command output from the CPU 16, and the actual velocity, i.e., the velocity feedback signal obtained by differentiating the position feedback signal using a differentiator 74. An adder 77 adds a current command obtained by multiplying the velocity deviation calculated by the adder 73 by the velocity proportional gain to a current command obtained by integrating the velocity deviation using an integrator 75 and multiplying the integration result by a velocity integral gain to generate a command current. A current control unit 78 adds the command current generated by the adder 77 to a command current obtained by multiplying an acceleration command output from the CPU 16 by an acceleration FF gain, and controls the supply of the command current to the Y motor 96.

[0034] The flow of generating control parameters using the control parameter generation method will be described. A verification test was conducted to detect the resonance frequency of the holding mechanism 8 in order to suppress vibration of the holding mechanism 8 due to resonance caused by driving the Y motor 96. In the verification test, a sweep sine wave signal (see Figure 4(A)) with a constant amplitude, positive and negative values, and whose frequency gradually changes over time after output begins was input to the Y motor 96 as a command current. The speed of the Y motor 96 (motor speed) (see Figure 4(B)) and the speed of the holding mechanism 8 (mechanism speed) (see Figure 4(C)) over time were then measured. By performing a fast Fourier transform on these, the relationship between the gain and frequency of the motor speed obtained by inputting a command current to the Y motor 96 (motor speed gain characteristics) (see Figure 4(D)) and the relationship between the gain and frequency of the mechanism speed of the holding mechanism 8, which is moved by the power of the Y motor 96 (mechanism speed gain characteristics) (see Figure 4(E)) can be obtained. As a result of the verification test, it was found that the resonance frequency of the holding mechanism 8 and the anti-resonance frequency of the Y motor 96 substantially coincided.

[0035] Every time the sewing material is changed depending on the sewing content, the mass of the sewing material and the holding mechanism 8 that holds the sewing material changes, and the resonance frequency of the holding mechanism 8 changes accordingly. Therefore, every time the sewing content is changed, the sewing machine 1 needs to regenerate the control parameters. In order to generate the control parameters, it is necessary to store the speed data measured over the entire period during which the sweep sine wave signal is input, and performing a fast Fourier transform places an extremely high calculation load on the CPU 16. Therefore, it is unrealistic to calculate the resonance frequency of the holding mechanism 8 using the procedure used in the verification test.

[0036] Therefore, in the control parameter generation method according to the present invention, the resonance frequency of the holding mechanism 8 that holds the sewing workpiece is estimated according to the algorithms described in (1) to (5) below. In addition, in parallel, the mass of the holding mechanism 8 is estimated according to the algorithms described in (11) to (16). Then, by generating control parameters based on the mass, the calculation load on the CPU 16 is reduced.

[0037] [Estimation of resonant frequency] (1) A sweep sine wave signal is generated and input to the Y motor 96. (2) Wait until a predetermined waiting time (e.g., 3 seconds) has elapsed since the Y motor 96 started to drive. From a verification test, it is estimated that the frequency that changes from the start of output of the sweep sine wave signal until the predetermined time has elapsed is different from the resonance frequency of the holding mechanism 8. For this reason, by waiting until the predetermined time has elapsed since the Y motor 96 started to drive and not performing any calculations, the CPU 16 further reduces the calculation load.

[0038] (3) After the Y motor 96 starts to drive and a waiting time has elapsed, calculations are started to convert the motor speed calculated based on the detection result of the encoder 58 into an absolute value, and a low-pass filter (LPF) is applied (see FIG. 5(A)). This makes it possible to calculate the maximum and minimum values ​​of the motor speed as positive values. Note that converting the motor speed into an absolute value and applying the LPF are performed sequentially, so the motor speed shown in FIG. 5(A) is an image of the motor speed after converting it into an absolute value and applying the LPF when a sweep sine wave signal is input over the entire time (for example, 15 seconds).

[0039] (4) The minimum value of the processed motor speed is calculated sequentially (see Figure 5(B)). Whenever the minimum value is updated, the update time (the time elapsed since the motor started to drive) is acquired. If a predetermined first time (e.g., 1 second) has passed without the minimum value being updated, the last updated minimum value is considered to be the minimum value, and the update time (e.g., 6.6 seconds) is saved. (5) The frequency of the sweep sine wave signal input during the update time of the saved minimum value is the anti-resonance frequency of the Y motor 96, and also the resonant frequency of the holding mechanism 8 according to the results of the verification test.

[0040] [Mass Estimation] (11) A sweep sine wave signal is generated and input to the Y motor 96. (12) The Y motor 96 waits until a predetermined time (for example, 3 seconds) has elapsed since the Y motor 96 started to drive. (13) The mathematical model for estimating the motor speed from the command current flowing through the Y motor 96 is set to 1 / Js, and the estimated motor speed value is calculated, where J is the inertia of the Y motor 96 and s is the Laplace operator.

[0041] (14) Calculate the inertia J using the recursive least squares method so that the difference between the motor speed calculated based on the detection result of the encoder 58 and the estimated value of the motor speed calculated in (13) becomes small. (15) At the update time when the minimum value (the anti-resonance frequency of the Y motor 96) is detected in (4), the calculation of the inertia J is completed. (16) A verification test is carried out in advance to determine the approximate formula "M = aJ + b" of the relationship between the mass M of the holding mechanism 8 and the inertia J of the Y motor 96 (see FIG. 5(C)). The inertia J finally calculated in (15) is applied to the approximate formula to calculate the mass M of the holding mechanism 8 (including the mass of the sewing workpiece).

[0042] The estimated value of inertia J is reliable if the mass M of the holding mechanism 8 estimated in this way is close to the actual mass of the holding mechanism 8. In controlling the supply of a command current to the Y motor 96 by the drive circuit 43, a command current according to the mass of the holding mechanism 8 can be generated by multiplying the acceleration command by the "estimated value of inertia J" as an acceleration FF gain. Then, a velocity integral gain and a velocity proportional gain are calculated based on the velocity closed-loop transfer function and set as control parameters.

[0043] 6 to 9, the control parameter generation process executed in the sewing machine 1 will be described. For example, when the user changes the product being made by the sewing machine 1 and makes another product, the user changes the sewing program and holds a different sewing object in the holding mechanism 8 to perform sewing. As the sewing object changes, the total mass of the sewing object and the holding mechanism 8 changes from the previous mass. When the total mass changes, the resonance frequency of the holding mechanism 8 changes, which may cause the holding mechanism 8 to vibrate during sewing. Therefore, when changing the sewing program, the user operates the switch group 13 of the operation unit 15 to instruct the execution of a maintenance operation.

[0044] 6, the CPU 16 of the sewing machine 1 reads a program from the ROM 17 and starts a control parameter generation process. The CPU 16 determines the waveform of the sweep sine wave signal to be input to the Y motor 96 (S11). That is, parameters such as the amplitude of the sweep sine wave, the output time, and the frequencies at the start and end of the output are determined. The CPU 16 then executes an inertia and resonance frequency calculation process (S12).

[0045] As shown in FIG. 7, the CPU 16 starts inputting the sweep sine wave signal, the waveform of which has been determined, to the Y motor 96 (S21), and starts measuring the elapsed time (S22). The elapsed time is the time that has elapsed since the input of the sweep sine wave signal started. The CPU 16 waits until the elapsed time exceeds the standby time (S23: NO). The standby time is the waiting time (e.g., 3 seconds) from the start of input of the sweep sine wave signal until the CPU 16 starts calculation. If the standby time has elapsed since the start of input of the sweep sine wave signal and the elapsed time exceeds the standby time (S23: YES), the CPU 16 acquires the time characteristic of the Y motor 96 (S24). The time characteristic is the motor speed of the Y motor 96 associated with the elapsed time.

[0046] The CPU 16 executes an inertia calculation process (S26). As shown in Fig. 8, if a predetermined calculation end time has passed (S31: YES), the CPU 16 does not calculate the inertia and returns to the inertia and resonance frequency calculation process. In this embodiment, the CPU 16 ends the inertia calculation when the anti-resonance frequency of the Y motor 96 is calculated (extracted), as the calculation end time. However, the inertia calculation may be ended when a sufficient number of calculations are performed over the elapsed time.

[0047] If the predetermined calculation end time has not passed (S31: NO), the CPU 16 calculates the inertia using the recursive least squares method (S32). As described above, the CPU 16 calculates the inertia using the recursive least squares method so as to minimize the difference between the estimated motor speed calculated from the command current using a mathematical model and the actually measured motor speed. After the calculation, the CPU 16 returns to the inertia and resonance frequency calculation process.

[0048] As shown in FIG. 7, the CPU 16 executes the resonance frequency calculation process (S27). As shown in FIG. 9, the CPU 16 converts the motor speed acquired as the time characteristic into an absolute value and then applies a low-pass filter (S41). This makes it possible to acquire the minimum value of the motor speed as a positive value. For convenience, the motor speed converted into an absolute value and applied with a low-pass filter is referred to as the machining speed. The CPU 16 determines whether the machining speed has updated its minimum value (S42). If the machining speed has updated its minimum value (S42: YES), the CPU 16 stores the minimum value and the update time in the storage device 19 (S43). The update time is the elapsed time since the machining speed updated its minimum value. The CPU 16 resets the non-update time (S44) and returns to the inertia and resonance frequency calculation process. The non-update time is measured as the time elapsed without the minimum value being updated. Therefore, if the minimum value is updated, the non-update time is reset.

[0049] 7, if the resonant frequency of the Y motor 96 has not been extracted in the resonant frequency calculation process (S28: NO) and the input of the sweep sine wave signal (full waveform) for the entire time (for example, 15 seconds) has not been completed (S29: NO), the CPU 16 returns the process to S24. The CPU 16 acquires the time characteristics for the next time (S24) and repeats the inertia calculation process (S26) and the resonant frequency calculation process (S27) for the acquired motor speed.

[0050] 9, if the minimum value of the machining speed has not been updated in S42 of the resonance frequency calculation process (S42: NO), the CPU 16 counts the non-update time (S46). Therefore, if the minimum value of the machining speed has been updated, the non-update time is reset, and if the minimum value has not been updated, the counting of the non-update time continues. As long as the non-update time is equal to or less than a predetermined first time (S47: NO), the CPU 16 returns to the inertia and resonance frequency calculation process. The first time is a reference time for the time during which the minimum value continues without being updated, and is, for example, one second.

[0051] If the non-update time exceeds the predetermined time (S47: YES), the CPU 16 extracts from the sweep waveform the frequency at the elapsed time equal to the update time stored in the storage device 19 (S48). That is, the update time in this case is the time when the updating of the minimum value stopped. The stored minimum value is the smallest of the successively updated minimum values. The extracted frequency corresponds to the anti-resonance frequency of the Y motor 96, i.e., the resonant frequency of the holding mechanism 8. The CPU 16 stores the resonant frequency of the holding mechanism 8 in the storage device 19. The CPU 16 returns to the inertia and resonant frequency calculation process.

[0052] 7, since the resonance frequency of the Y motor 96 has been extracted in the resonance frequency calculation process (S28: YES), the CPU 16 returns to the control parameter generation process. Note that if the sweep end time is reached without the minimum value being updated and the non-update time is less than or equal to the predetermined time (S29: YES), the CPU 16 also returns to the control parameter generation process. The sweep end time is the time when the input of the entire sweep sine wave signal is completed, and is, for example, when the elapsed time reaches 15 seconds. 6, the CPU 16 calculates the mass of the holding mechanism 8 by applying the inertia calculated using the recursive least squares method to an approximation formula (S13). The CPU 16 displays the mass of the holding mechanism 8 on the display unit 14 of the operation unit 15 (S14). The displayed mass includes the mass of the sewing workpiece held by the holding mechanism 8.

[0053] The user determines whether the displayed mass is appropriate and inputs the result of the determination by operating the switch group 13. If the CPU 16 determines, through the user's operation, that the displayed mass is not appropriate (S16: NO), the CPU 16 ends the control parameter generation process without changing the control parameters. If the CPU 16 determines that the mass is appropriate (S16: YES), the CPU 16 calculates control gains (speed proportional gain and speed integral gain) based on the velocity closed-loop transfer function (S17). The CPU 16 displays a query on the display unit 14 of the operation unit 15 asking whether the control parameters may be changed using the calculated control gains. If the user selects not to change the control parameters (S18: NO), the control parameter generation process ends without changing the control parameters. If the user selects to change the control parameters (S18: YES), the CPU 16 sets the calculated control gains as the control parameters (S19), and ends the control parameter generation process.

[0054] As described above, in the control parameter generation process, the characteristics of the motor speed and elapsed time are sequentially acquired, and the machining speed is sequentially calculated by converting the motor speed to an absolute value and applying a low-pass filter. This makes it possible to calculate a minimum value from the machining speed, so the inertia J of the Y motor 96 is calculated based on the motor speed up to the update time at which the first minimum value was obtained. The mass M of the holding mechanism 8 including the sewing workpiece is then calculated from the inertia J, thereby calculating the control parameters of the Y motor 96. In this way, the control parameter generation method requires less memory capacity and requires less calculation load than when the characteristics of the motor speed and elapsed time are acquired over an entire period and, after acquisition is complete, parameters are calculated based on all the characteristics over that period, and therefore can be implemented with inexpensive hardware.

[0055] In the control parameter generation process, the inertia J is calculated each time using the recursive least squares method, which requires less memory capacity and a smaller calculation load than when calculating everything from scratch using the motor speed up to that point each time the motor speed is obtained, and therefore can be achieved with inexpensive hardware.

[0056] In the control parameter generation process, the user determines whether the calculation result of mass M is appropriate. If a mass that is significantly different from the mass M of the holding mechanism 8 including the sewing workpiece is calculated due to, for example, an external disturbance, the calculation of the control parameters based on that mass can be stopped, thereby preventing the Y motor 96 from being controlled with inappropriate parameters.

[0057] It is known in advance that the calculated resonance frequency of the holding mechanism 8 including the sewing material corresponds to the anti-resonance frequency of the Y motor 96. Therefore, in the control parameter generation process, for example, by calculating the control parameters so that the gain characteristics of the closed loop of the motor speed attenuate at the resonance frequency of the holding mechanism 8 including the sewing material, it is possible to suppress the resonance of the holding mechanism 8 including the sewing material and realize motor control that allows the holding mechanism 8 including the sewing material to be stably conveyed.

[0058] By controlling the Y motor 96 using the control parameters generated by the control parameter generation process, the sewing machine 1 can suppress resonance of the holding mechanism 8 holding the sewing material and stably transport the holding mechanism 8 including the sewing material.

[0059] Furthermore, in the control parameter generation process, the minimum value is obtained based on the minimum value of the machining speed calculated successively. Therefore, compared to the case where the characteristics of the motor speed and elapsed time are obtained over the entire period, and after the acquisition is completed, the machining speed is calculated and the minimum value is obtained, the memory capacity used is smaller and the calculation load is also smaller, so that it can be realized with inexpensive hardware.

[0060] In the above description, the Y motor 96 is an example of a "motor" of the present invention. The drive circuit 43 is an example of a "motor control device" of the present invention. The sewing machine 1 is an example of a "conveying device" and a "sewing device" of the present invention. The CPU 16 that performs the processing of S24 is an example of a "time characteristic acquisition process" of the present invention. The CPU 16 that performs the processing of S41 is an example of a "speed processing process" of the present invention. The CPU 16 that performs the processing of S43 is an example of a "minimum value acquisition process" of the present invention. The CPU 16 that performs the processing of S32 is an example of an "inertia calculation process" of the present invention. The CPU 16 that performs the processing of S13 is an example of a "mass calculation process" of the present invention. The CPU 16 that performs the processing of S17 is an example of a "parameter calculation process" of the present invention.

[0061] The CPU 16 performing the process of S14 is an example of the "mass presentation step" of the present invention. The CPU 16 performing the process of S16 is an example of the "determination input step" of the present invention. The CPU 16 performing the process of S48 is an example of the "resonance frequency acquisition step" of the present invention.

[0062] The present invention is not limited to the above embodiment and can be modified in various ways. In the above embodiment, calculation of the resonance frequency of the holding mechanism 8 is completed when the minimum value of the machining speed is acquired as a local minimum value. However, the resonance frequency of the holding mechanism 8 at two or more different frequencies may be calculated. Furthermore, the resonance frequency of the Y motor 96 may be calculated based on the maximum value of the machining speed. Similarly, the resonance frequency of the Y motor 96 at two or more different frequencies may be calculated. Specifically, as shown in FIG. 10, when the CPU 16 executes the modified example of the resonance frequency calculation process, the CPU 16 converts the motor speed acquired as the time characteristic in S24 into an absolute value and further applies a low-pass filter (S61).

[0063] The CPU 16 determines whether the minimum value update setting is set (S62). In the modified example of the resonance frequency calculation process, the minimum value and maximum value of the machining speed are calculated alternately, and which value to calculate is determined by setting the mode to minimum value update setting or maximum value update setting. The minimum value update setting is set by default. If the mode setting is minimum value update setting (S62: YES), the CPU 16 determines whether the machining speed has updated its minimum value (S71). If the machining speed has updated its minimum value (S71: YES), the CPU 16 stores the minimum value and the minimum value update time in the storage device 19 (S72). The CPU 16 resets the minimum value non-update time (S73) and returns to the inertia and resonance frequency calculation process.

[0064] If the minimum value of the machining speed has not been updated in S71 (S71: NO), the CPU 16 counts the minimum value non-update time (S74). If the minimum value non-update time is equal to or shorter than the first time (S76: NO), the CPU 16 returns to the inertia and resonance frequency calculation process. If the minimum value non-update time exceeds a predetermined time (S76: YES), the CPU 16 extracts from the sweep waveform a frequency at an elapsed time equal to the minimum value update time stored in the storage device 19 (S77). The extracted frequency corresponds to the anti-resonance frequency of the Y motor 96, i.e., the resonance frequency of the holding mechanism 8. The CPU 16 stores the Nth resonance frequency of the holding mechanism 8 in the storage device 19. Note that N is a variable, and is initially set to 1. The CPU 16 resets the maximum value and increments the value of N by 1 (S78). The CPU 16 changes the mode setting to maximum value update setting (S79) and returns to the inertia and resonance frequency calculation process.

[0065] If the mode setting is the maximum value update setting (S62: NO), the CPU 16 determines whether the maximum value of the machining speed has been updated (S81), as shown in Fig. 11. If the maximum value of the machining speed has been updated (S81: YES), the CPU 16 stores the maximum value and the maximum value update time in the storage device 19 (S82). The CPU 16 resets the maximum value non-update time (S83), and returns to the inertia and resonance frequency calculation process.

[0066] If the maximum value of the machining speed has not been updated in S81 (S81: NO), the CPU 16 counts the maximum value non-update time (S84). If the maximum value non-update time is equal to or shorter than a predetermined second time (e.g., 1 second) (S86: NO), the CPU 16 returns to the inertia and resonance frequency calculation process. If the maximum value non-update time exceeds the second time (S86: YES), the CPU 16 extracts from the sweep waveform a frequency at the same elapsed time as the maximum value update time stored in the storage device 19 (S87). The extracted frequency corresponds to the resonance frequency of the Y motor 96, i.e., the anti-resonance frequency of the holding mechanism 8. The CPU 16 stores the Mth resonance frequency of the Y motor 96 in the storage device 19. Note that M is a variable, and is initially set to 1. The CPU 16 resets the minimum value and increments the value of M by 1 (S88). The CPU 16 changes the mode setting to the minimum value update setting (S89), and returns to the inertia and resonance frequency calculation process.

[0067] In the above description, the maximum value update time is an example of the "second time" of the present invention. The CPU 16 performing the processing of S82 is an example of the "maximum value acquisition step" of the present invention. The CPU 16 performing the processing of S88 is an example of the "minimum value initialization step" of the present invention. The CPU 16 performing the processing of S78 is an example of the "maximum value initialization step" of the present invention. The CPU 16 performing the processing of S87 is an example of the "motor resonant frequency acquisition step" of the present invention.

[0068] When the above-described modified resonance frequency calculation process is performed, the process of S28 in the inertia and resonance frequency calculation process may not be performed, and the process may proceed to S29 after S27. Furthermore, in the process of S21 or S22, default settings (minimum value update setting of mode setting, N=1, M=1) may be defined. In the control parameter generation process, for example, by calculating the control parameters so that the gain characteristics of the closed loop of the motor speed attenuate at the resonance frequency of the holding mechanism 8 including the sewing product and the resonance frequency of the motor, resonance of the holding mechanism 8 including the sewing product and the motor can be suppressed, thereby realizing control of the Y motor 96 so that the holding mechanism 8 including the sewing product is conveyed more stably.

[0069] Furthermore, in this modified example, the minimum and maximum values ​​can be obtained based on the minimum and maximum values ​​of the machining speed calculated sequentially. Therefore, compared to the case where the characteristics of the motor speed and elapsed time are obtained over the entire period, and after the acquisition is completed, the machining speed is calculated and the minimum value is calculated, the memory capacity used is smaller and the calculation load is also smaller, so that it can be realized with inexpensive hardware.

[0070] In the inertia and resonance frequency calculation process, various calculations are started after waiting for the elapsed time to exceed the waiting time. However, it is also possible to input to the Y motor 96 a sweep sine wave signal in which the waveform corresponding to the waiting time is deleted from the sweep waveform without setting a waiting time. In S14 and S16, the user is queried as to whether the calculated mass is appropriate, but this process may be omitted. If it is determined in S16 that the calculated mass is not appropriate, the control parameter generation process was terminated. However, the control parameter generation process may be returned to S11 and started again. Also, the sweep waveform may be changed at that time. Furthermore, in S18, the user is asked whether to set the control gain as a control parameter. However, the control gain may be set as a control parameter without confirmation. [Explanation of symbols]

[0071] 1 sewing machine 6 Needle bar mechanism 8 Retention mechanism 10. Feed mechanism 16 CPU 19 Storage device 43 Drive circuit 96 Y motor

Claims

1. A control parameter generation method for a transport device that transports an object to be transported, the control parameter generation method comprising: generating control parameters used by the motor control device in accordance with a mass of the object to be transported; a time characteristic acquisition step of inputting a sweep signal having a time characteristic in which the frequency of the signal value changes over time to the motor, and acquiring a characteristic of the motor speed and elapsed time of the motor; a speed processing step of calculating a processing speed by converting the acquired motor speed into an absolute value and applying a low-pass filter to the motor speed; a minimum value acquiring step of calculating a minimum value of the machining speed of the motor speed for each elapsed time acquired after a predetermined waiting time has elapsed since the start of input of the sweep signal, and acquiring a first time when the minimum value first exhibits a minimum value and the minimum value; an inertia calculation step of calculating an inertia of the motor based on the motor speed acquired during a period from the elapse of the waiting time until the first time when the minimum value is acquired and a mathematical model; a mass calculation step of calculating the mass of the object to be conveyed based on the calculated inertia and an approximation formula; a parameter calculation step of calculating the control parameters based on the calculated mass of the object to be conveyed; A control parameter generation method comprising:

2. In the inertia calculation step, the inertia is calculated using a recursive least squares method so that a difference between the motor speed and a motor speed estimate value previously obtained from the mathematical model becomes small.

2. The control parameter generating method according to claim 1, wherein:

3. a mass presenting step of presenting the mass of the object to be transported calculated in the mass calculating step; a judgment input step of receiving an input of a judgment as to whether the presented mass is appropriate; Further provided with When a determination that the mass is inappropriate is input, the calculation of the control parameters in the parameter calculation step is stopped.

3. The control parameter generating method according to claim 1, wherein:

4. a resonance frequency acquiring step of calculating a frequency input to the motor at the first time when the machining speed becomes the minimum value based on the time characteristic of the sweep signal, and acquiring the frequency as a resonance frequency of the conveyed object; The parameter calculation step includes: Calculating the control parameter based on the calculated resonance frequency and the mass of the object to be transported.

2. The control parameter generating method according to claim 1, wherein:

5. a maximum value acquisition step of calculating a maximum value of the machining speed of the motor speed for each elapsed time acquired after the waiting time has elapsed since the start of input of the sweep signal, and acquiring a second time when the maximum value first exhibits a maximum value and the maximum value; a motor resonance frequency acquisition step of calculating a frequency input to the motor at the second time when the machining speed reaches the maximum value based on the time characteristics of the sweep signal, and acquiring the frequency as a resonance frequency of the motor; Further provided with The parameter calculation step includes: calculating the control parameter based on the calculated resonance frequency of the object to be conveyed, the resonance frequency of the motor, and the mass; 5. The control parameter generating method according to claim 4, wherein:

6. The minimum value acquisition step successively calculates the minimum value of the machining speed of the motor speed, updates the smallest value, and sets the value that has not been updated for more than a predetermined first time as the minimum value.

5. The control parameter generating method according to claim 1 or 4,

7. the minimum value acquisition step successively calculates the minimum value of the machining speed of the motor speed, updates the smallest value, and sets the value that has not been updated for more than a predetermined first time as the minimum value; the maximum value acquisition step successively calculates the maximum value of the machining speed of the motor speed, updates the largest value, and sets the value that has not been updated for more than a predetermined second time as the maximum value; a maximum value initialization step of initializing the maximum value when the first time period has elapsed from the first time point; a minimum value initialization step of initializing the minimum value when the second time period has elapsed from the second time; Further, 6. The control parameter generating method according to claim 5,

8. The conveying device is used in a sewing device, the conveying object is a holding mechanism that holds a sewing workpiece, the transmission mechanism is a feed mechanism that moves the holding mechanism relative to a needle bar mechanism that drives a needle bar; The motor drives the feed mechanism.

2. The control parameter generating method according to claim 1, wherein:

9. A control parameter generation program for a conveyance device that conveys the object to be conveyed, the control parameter generation program generating control parameters used by the motor control device in accordance with a mass of the object to be conveyed, the control parameter generation program comprising: The computer of the transport device a time characteristic acquisition step of inputting a sweep signal having a time characteristic in which the frequency of the signal value changes over time to the motor, and acquiring a characteristic of the motor speed and elapsed time of the motor; a speed processing step of calculating a processing speed by converting the acquired motor speed into an absolute value and applying a low-pass filter; a minimum value acquisition step of calculating a minimum value of the machining speed of the motor speed for each elapsed time acquired after a predetermined waiting time has elapsed since the start of input of the sweep signal, and acquiring a first time when the minimum value first exhibits a minimum value and the minimum value; an inertia calculation step of calculating an inertia of the motor based on the motor speed acquired during a period from the elapse of the waiting time until the first time when the minimum value is acquired and a mathematical model; a mass calculation step of calculating the mass of the object to be conveyed based on the calculated inertia and an approximation formula; a parameter calculation step of calculating the control parameters based on the calculated mass of the object to be conveyed; A control parameter generation program characterized by executing the above.

10. In a conveyance device that conveys the object to be conveyed, the conveyance device includes a motor, a motor control device that controls the motor, and a transmission mechanism that transmits power generated by the motor to the object to be conveyed, and generates control parameters used by the motor control device in accordance with the mass of the object to be conveyed, The computer of the transport device a time characteristic acquisition step of inputting a sweep signal having a time characteristic in which the frequency of the signal value changes over time to the motor, and acquiring a characteristic of the motor speed and elapsed time of the motor; a speed processing step of calculating a processing speed by converting the acquired motor speed into an absolute value and applying a low-pass filter; a minimum value acquisition step of calculating a minimum value of the machining speed of the motor speed for each elapsed time acquired after a predetermined waiting time has elapsed since the start of input of the sweep signal, and acquiring a first time when the minimum value first exhibits a minimum value and the minimum value; an inertia calculation step of calculating an inertia of the motor based on the motor speed acquired during a period from the elapse of the waiting time until the first time when the minimum value is acquired and a mathematical model; a mass calculation step of calculating the mass of the object to be conveyed based on the calculated inertia and an approximation formula; a parameter calculation step of calculating the control parameters based on the calculated mass of the object to be conveyed; A storage medium storing a program for executing the above.

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