Motor control device, motor control method, and program recording medium

Abstract

A motor control device (10) includes a control section (20) that generates a drive signal for driving a motor (50) based on a command signal for positioning a movable section (60) connected to the motor (50) at a target position and an encoder signal showing a position of the motor (50) detected by an encoder (51), and outputs the generated drive signal to the motor (50), and a generation method changing section (30) that changes a generation method of the drive signal by the control section (20) based on a position sensor signal showing a position of a target position detected by a position sensor (61) installed on the movable section (60).

Description

Technical Field

[0001] This disclosure relates to an electric motor control device for controlling an electric motor. Background Technology

[0002] Patent Document 1 and Patent Document 2 disclose an electric motor control device for controlling an electric motor.

[0003] In the aforementioned conventional electric motor control devices, the electric motor is controlled based on information detected by sensors installed in the movable part connected to the electric motor.

[0004] (Existing technical literature)

[0005] (Patent Documents)

[0006] Patent Document 1: Japanese Patent No. 6824593

[0007] Patent Document 2: Japanese Patent Application Publication No. 2005-267138

[0008] However, there is room for improvement in the electric motor devices disclosed in the aforementioned Patent Documents 1 and 2. Summary of the Invention

[0009] Therefore, the purpose of this disclosure is to provide an electric motor control device, etc., that can be further improved.

[0010] One aspect of this disclosure relates to an electric motor control device comprising: a control unit that generates a drive signal for driving an electric motor based on a command signal and an encoder signal, and outputs the generated drive signal to the electric motor, wherein the command signal is used to position a movable part connected to the electric motor at a target position, and the encoder signal indicates the position of the electric motor detected by an encoder; and a generation method modification unit that modifies the generation method of the drive signal generated by the control unit based on a position sensor signal indicating a detected target position, wherein the detected target position is the position of the target position detected by a position sensor installed on the movable part.

[0011] One aspect of this disclosure relates to an electric motor control method comprising the following steps: a control step, generating a drive signal for driving an electric motor based on a command signal and an encoder signal, and outputting the generated drive signal to the electric motor, wherein the command signal is used to position a movable part connected to the electric motor at a target position, and the encoder signal indicates the position of the electric motor detected by the encoder; and a generation method modification step, modifying the generation method of generating the drive signal in the control step based on a position sensor signal indicating the detected target position, wherein the detected target position is the position of the target position detected by a position sensor installed on the movable part.

[0012] One aspect of this disclosure relates to a program recording medium containing a program for causing a motor control device controlling an electric motor to perform motor control processing, the motor control processing including the following steps: a control step, generating a drive signal for driving the motor based on a command signal and an encoder signal, and outputting the generated drive signal to the motor, the command signal being used to position a movable part connected to the motor at a target position, the encoder signal indicating the position of the motor detected by the encoder; and a generation method modification step, modifying the generation method of generating the drive signal in the control step based on a position sensor signal indicating the detected target position, the detected target position being the position of the target position detected by a position sensor installed on the movable part.

[0013] The electric motor control device and the like disclosed in one aspect are expected to be further improved. Attached Figure Description

[0014] Figure 1 This is a block diagram showing the configuration of the electric motor control system according to Embodiment 1.

[0015] Figure 2 This is a flowchart of the first motor control process involved in Implementation Method 1.

[0016] Figure 3 This is a schematic diagram illustrating a first specific example of operation performed by the motor control device according to Embodiment 1.

[0017] Figure 4 This is a block diagram showing the configuration of the electric motor control system according to Embodiment 2.

[0018] Figure 5 This is a flowchart of the second motor control process involved in Implementation Method 2.

[0019] Figure 6This is a block diagram showing the configuration of the electric motor control system according to Embodiment 3.

[0020] Figure 7 This is a flowchart of the third motor control process involved in Implementation Method 3. Detailed Implementation

[0021] (The process of obtaining one form of this disclosure)

[0022] Even when a motor control device drives a motor based on a command signal for positioning a movable part connected to the motor at a target position and an encoder signal indicating the position of the motor detected by the encoder, there may still be instances where the position of the movable part deviates from the actual target position.

[0023] The inventors discovered the above-mentioned problem and conceived of the following motor control device, etc., for solving this problem.

[0024] One aspect of this disclosure relates to an electric motor control device comprising: a control unit that generates a drive signal for driving an electric motor based on a command signal and an encoder signal, and outputs the generated drive signal to the electric motor, wherein the command signal is used to position a movable part connected to the electric motor at a target position, and the encoder signal indicates the position of the electric motor detected by an encoder; and a generation method modification unit that modifies the generation method of the drive signal generated by the control unit based on a position sensor signal indicating a detected target position, wherein the detected target position is the position of the target position detected by a position sensor installed on the movable part.

[0025] The motor control device described above modifies the method for generating the drive signal for driving the motor according to the target position detected by the position sensor installed on the movable part. Therefore, the motor control device described above enables the movable part to be positioned at the actual target position.

[0026] Thus, the motor control device configured as described above provides a motor control device that can be further improved.

[0027] Furthermore, it may also include a switching unit that switches the changes to the generation method performed by the generation method change unit to be valid or invalid.

[0028] Accordingly, it is possible to switch the method of generating the drive signal for driving the motor to be effective or ineffective based on the position of the detection target detected by the position sensor.

[0029] Alternatively, if there is a positional deviation between the target position and the detection target position, the generation method modification unit may modify the generation method by the following steps (1) and (2): (1) generating a correction value for correcting the command signal so that the target position changes with the positional deviation; (2) generating the drive signal based on the encoder signal and the command signal corrected by the correction value.

[0030] Therefore, the position of the movable part can be positioned at the target position by using the command signal corrected by the correction value.

[0031] Alternatively, the generation method modification unit may further output the correction value to the controller that generates the instruction signal.

[0032] Accordingly, the controller can generate a command signal that reflects the correction value.

[0033] Alternatively, if there is a positional deviation between the target position and the detection target position, the generation method modification unit may modify the generation method by the following steps (1) to (3): (1) temporarily stopping the motor; (2) generating a correction value for correcting the command signal after a first predetermined time has elapsed since the motor was temporarily stopped, so that the target position changes with the positional deviation; and (3) generating the drive signal based on the encoder signal and the command signal corrected by the correction value.

[0034] The motor control device described above can generate a correction value after the vibration of the movable part is suppressed. Therefore, the position of the movable part can be positioned at the target position with higher precision.

[0035] Alternatively, the generation method modification unit may further output the correction value to the controller that generates the instruction signal.

[0036] Accordingly, the controller can generate a command signal that reflects the correction value.

[0037] Alternatively, if the first specified condition is met, the generation method modification unit may reset the correction value.

[0038] Accordingly, it is possible to suppress the excessively large correction value caused by the accumulation of positional deviation of the movable part relative to the target position, and to suppress the adverse effects caused by resetting the correction value.

[0039] Alternatively, the first specified condition may include the condition that the motor is working, and the generation method modification unit may reset the correction value in such a way that the correction value gradually approaches zero and eventually becomes zero when the motor is working.

[0040] Generally speaking, resetting the calibration value when the motor is stopped will result in the undesirable effect of the motor suddenly starting.

[0041] The motor control device configured as described above can suppress the occurrence of such adverse effects. Furthermore, the motor control device configured as described above can also suppress the adverse effects caused by setting the correction value to zero all at once.

[0042] Alternatively, the generation method modification unit may modify the gain parameter based on the position sensor signal and generate the drive signal, thereby modifying the generation method. The gain parameter is used to determine the gain of the drive signal for the command signal.

[0043] Therefore, the gain parameters can be changed based on the position sensor signal.

[0044] Alternatively, the generation method modification unit may also modify the generation method based on an acceleration sensor signal, which indicates the acceleration of the movable part detected by an acceleration sensor installed on the movable part.

[0045] Therefore, the position of the movable part can be positioned at the target location with higher precision.

[0046] Furthermore, it may also include a switching unit that switches the changes to the generation method performed by the generation method change unit to be valid or invalid.

[0047] Accordingly, it is possible to switch the method of generating the drive signal for driving the motor to be effective or ineffective based on the position of the detection target detected by the position sensor and the acceleration of the movable part detected by the acceleration sensor.

[0048] Alternatively, when there is a positional deviation between the target position and the detected target position, if the acceleration of the movable part indicated by the acceleration sensor signal is below a predetermined threshold and more than a second predetermined time has elapsed, the generation method can be modified as follows (1) and (2): (1) a correction value for correcting the command signal is generated so that the target position changes with the positional deviation; (2) the drive signal is generated based on the encoder signal and the command signal corrected by the correction value.

[0049] The motor control device described above can generate a correction value after the vibration of the movable part is suppressed. Therefore, the position of the movable part can be positioned at the target location with higher precision.

[0050] Alternatively, if the second specified condition is met, the generation method modification unit may reset the correction value.

[0051] Accordingly, it is possible to suppress the excessively large correction value caused by the accumulation of positional deviation of the movable part relative to the target position, and to suppress the adverse effects caused by resetting the correction value.

[0052] Alternatively, the second specified condition may include the condition that the motor is working, and the generation method modification unit may reset the correction value in such a way that the absolute value of the correction value gradually approaches zero and eventually becomes zero when the motor is working.

[0053] Generally speaking, resetting the calibration value when the motor is stopped will result in the undesirable effect of the motor suddenly starting.

[0054] The motor control device configured as described above can suppress the occurrence of such adverse effects. Furthermore, the motor control device configured as described above can also suppress the adverse effects caused by setting the correction value to zero all at once.

[0055] Alternatively, the generation method modification unit may further output the correction value to the controller that generates the instruction signal.

[0056] Accordingly, the controller can generate a command signal that reflects the correction value.

[0057] Alternatively, the generation method modification unit may modify the gain parameter and generate the drive signal based on the position sensor signal and / or the acceleration sensor signal, thereby modifying the generation method. The gain parameter is used to determine the gain of the drive signal for the command signal.

[0058] Therefore, the gain parameters can be changed based on position sensor signals and / or acceleration sensor signals.

[0059] One aspect of this disclosure relates to an electric motor control method comprising the following steps: a control step, generating a drive signal for driving an electric motor based on a command signal and an encoder signal, and outputting the generated drive signal to the electric motor, wherein the command signal is used to position a movable part connected to the electric motor at a target position, and the encoder signal indicates the position of the electric motor detected by the encoder; and a generation method modification step, modifying the generation method of generating the drive signal in the control step based on a position sensor signal indicating the detected target position, wherein the detected target position is the position of the target position detected by a position sensor installed on the movable part.

[0060] The aforementioned motor control method modifies the method for generating the drive signal for driving the motor according to the detected target position detected by the position sensor installed on the movable part. Accordingly, the aforementioned motor control method enables the movable part to be positioned at the actual target position.

[0061] Thus, the above-described motor control method provides a motor control device that can be further improved.

[0062] One aspect of this disclosure relates to a program recording medium containing a program for causing a motor control device controlling an electric motor to perform motor control processing, the motor control processing including the following steps: a control step, generating a drive signal for driving the motor based on a command signal and an encoder signal, and outputting the generated drive signal to the motor, the command signal being used to position a movable part connected to the motor at a target position, the encoder signal indicating the position of the motor detected by the encoder; and a generation method modification step, modifying the generation method of generating the drive signal in the control step based on a position sensor signal indicating the detected target position, the detected target position being the position of the target position detected by a position sensor installed on the movable part.

[0063] The above procedure modifies the method for generating the drive signal used to drive the motor according to the target position detected by the position sensor installed on the movable part. Accordingly, by recording the above procedure on a medium, the position of the movable part can be positioned at the actual target position.

[0064] Thus, by recording the above procedure on the medium, a motor control device that can be expected to be further improved is provided.

[0065] The following description, with reference to the accompanying drawings, illustrates a specific example of an electric motor control device according to one aspect of this disclosure. The embodiments shown herein are merely examples of this disclosure. Therefore, the numerical values, shapes, constituent elements, arrangements and connections of constituent elements, as well as steps (processes) and their order shown in the following embodiments are all examples and are not intended to limit the scope of this disclosure. Furthermore, the figures are schematic diagrams and not rigorous illustrations. In the various figures, substantially identical components are given the same symbols, and repeated descriptions are omitted or simplified.

[0066] (Implementation Method 1)

[0067] The electric motor control system according to Embodiment 1 will be described below. This electric motor control system is a system that controls an electric motor to move a movable part connected to the motor to a target position. This electric motor control system may be, for example, a production apparatus for mounting components onto a substrate.

[0068] <Composition>

[0069] Figure 1 This is a block diagram showing the configuration of the electric motor control system 1 according to Embodiment 1.

[0070] like Figure 1 As shown, the electric motor control system 1 includes: an electric motor control device 10, an electric motor 50, a movable part 60, a controller 70, an encoder 51, a position sensor 61, and an object 65.

[0071] The electric motor 50 is driven by a drive signal output from the electric motor control device 10. Here, the electric motor 50 is described as a rotary electric motor. However, the electric motor 50 is not limited to a rotary electric motor; for example, it can also be a linear electric motor.

[0072] The drive signal is, for example, the current used to rotate the motor 50.

[0073] The encoder 51 detects the position of the motor 50 and outputs an encoder signal showing the detected position of the motor 50 to the motor control device 10.

[0074] The movable part 60 is connected to the electric motor 50. For example, in the case where the electric motor control system 1 is a production device that mounts components onto a substrate, the movable part 60 is a head that transports the components to the mounting position.

[0075] The controller 70 generates a command signal to position the movable part 60 at a target position and outputs the generated command signal to the motor control device 10. The command signal may be, for example, a position command signal, a speed command signal, an acceleration command signal, or a torque command signal. The position command signal indicates a position command to position the movable part 60 at the target position; the speed command signal indicates a speed command to position the movable part 60 at the target position; the acceleration command signal indicates an acceleration command to position the movable part 60 at the target position; and the torque command signal indicates a torque command to position the movable part 60 at the target position.

[0076] Object 65 is placed at the target location. That is, the position of object 65 is the target location.

[0077] A position sensor 61 is mounted on the movable part 60 to detect the position of the object 65 and outputs a position sensor signal showing the detected position of the object 65 to the motor control device 10. In other words, the position sensor 61 detects the position of the target position, that is, the actual target position, and outputs a sensor signal showing the detected target position to the motor control device 10.

[0078] The position sensor 61 can be implemented by a camera device, for example. In this case, the camera device may capture an image of the camera range, and if the object 65 is included in the camera range, perform image processing on the captured image to calculate the positional deviation of the movable part 60 relative to the object 65 at the target position, so as to detect the target position.

[0079] Alternatively, the position sensor 61 can be implemented by, for example, a displacement sensor. For example, the position sensor 61 can be implemented by a transmissive laser displacement sensor. When the object 65 is located in a position that blocks the laser, the position of the object 65 with a predetermined amount or pattern of light blocking is taken as the target position, and the position deviation of the movable part 60 relative to the target position is calculated as the target position for detection.

[0080] The motor control device 10 receives input command signals, encoder signals, and position sensor signals, and outputs drive signals.

[0081] The motor control device 10 can be implemented, for example, in a computer device equipped with a processor, memory, and input / output interfaces, by having the processor execute a program stored in the memory. Alternatively, the motor control device 10 can also be implemented, for example, by dedicated hardware circuitry. Furthermore, the motor control device 10 can also be implemented by a combination of a computer device and dedicated hardware circuitry, wherein the computer device is a means by which a processor executes a program stored in the memory.

[0082] The motor control device 10 includes: a control unit 20, a generation method change unit 30, and a switching unit 40.

[0083] The control unit 20 generates a motor drive signal for driving the motor 50 based on the command signal output from the controller 70 and the encoder signal output from the encoder 51, and outputs the generated motor drive signal to the motor 50.

[0084] The control unit 20 includes a drive signal generation unit 21 and a correction unit 22.

[0085] The correction unit 22 stores the correction values ​​output from the generation method change unit 30. Here, the correction value is a signal used to correct the command signal, causing the target position to change by the position deviation when there is a positional deviation between the target position indicated by the command signal and the detected target position indicated by the position sensor signal. In this case, it is assumed that, in the initial state, the correction unit 22 stores a correction value that does not correct the command signal. Furthermore, this will be described with the case where the correction value for not correcting the command signal is 0 (zero).

[0086] When a command signal is input, the correction unit 22 corrects the command signal according to the stored correction value and outputs the corrected command signal (hereinafter also referred to as "corrected command signal") to the drive signal generation unit 21.

[0087] The correction unit 22 can also reset the correction value (set it to an initial value) when certain conditions are met. Preferably, the specified conditions are those that can suppress any adverse effects that may occur due to resetting the correction value. For example, the specified conditions could be that the motor 50 is operating.

[0088] Generally, if the calibration value is reset when the motor 50 is stopped, the motor 50 will suddenly start, which is an undesirable effect. Therefore, the calibration unit 22 can suppress the occurrence of the above-mentioned undesirable effect by resetting the calibration value when the motor 50 is running.

[0089] Alternatively, while the motor 50 is operating, the correction unit 22 can further reset the correction value by gradually approaching and eventually reducing it to zero. This further suppresses any adverse effects that might occur if the correction value were reduced to zero all at once.

[0090] The drive signal generation unit 21 performs feedback control on the calibrated command signal output from the calibration unit 22, and feeds back the encoder signal output from the encoder 51 to the calibrated command signal, thereby generating a drive signal and outputting the generated drive signal to the motor 50.

[0091] The generation method modification unit 30 changes the generation method of the drive signal generated by the control unit 20 based on the position sensor signal.

[0092] The generation method change unit 30 includes a correction value generation unit 31 and a gain change unit 32.

[0093] When there is a positional deviation between the target position indicated by the command signal and the detection target position indicated by the position sensor signal, the correction value generation unit 31 generates a correction value for correcting the command signal and outputs the generated correction value to the correction unit 22 so that the target position changes according to the positional deviation.

[0094] The correction value generated by the correction value generation unit 31 is output to the correction unit 22, thereby updating the correction value stored in the correction unit 22. Accordingly, the correction value generation unit 31 changes the method by which the control unit 20 generates the drive signal by generating the drive signal based on the encoder signal and the correction command value corrected by the updated correction value.

[0095] The correction value generation unit 31 can also output the generated correction value to the controller 70. Accordingly, the controller 70 can generate a command signal that reflects the correction value.

[0096] The gain modification unit 32 modifies the gain parameter of the drive signal generation unit 21 based on the position sensor signal, and this gain parameter is also used to determine the gain of the drive signal for the command signal. Accordingly, the gain modification unit 32 modifies the drive signal generation method of the control unit 20 by generating the drive signal with the gain determined by the modified gain parameter. For example, the gain modification unit 32 may also modify the gain parameter of the drive signal generation unit 21 when the position deviation between the target position and the position of the movable part 60 indicated by the position sensor signal is greater than or equal to a predetermined value.

[0097] The switching unit 40 switches the change of the generation method performed by the generation method change unit 30 to be effective or ineffective. The generation method is the generation method of the drive signal generated by the control unit 20.

[0098] The switching unit 40 may also perform the above-mentioned switching according to the instructions from the controller 70, and may also perform the above-mentioned switching according to the received user operation when the switching unit 40 has the function of accepting the operation from the user using the motor control device 10.

[0099] Here, we will take as an example the generation method modification unit 30 operates in either a first operating mode or a second operating mode, and illustrate by taking the switching unit 40 switching the operating mode of the generation method modification unit 30 between the first and second operating modes. The first operating mode is one that enables the modification of the generation method for generating drive signals by the control unit 20, while the second operating mode is one that disables the modification. Accordingly, the switching unit 40 switches the modification of the generation method performed by the generation method modification unit 30 to either enable or disable the modification, whereby the generation method is the method for generating drive signals by the control unit 20.

[0100] <Work>

[0101] The operation of the motor control device 10 described above will now be explained.

[0102] The motor control unit 10 executes a first motor control process to control the motor 50 based on command signals, encoder signals, and position sensor signals. The first motor control process is initiated, for example, by a user of the motor control unit 10 performing an operation to start the first motor control process on the motor control unit 10.

[0103] Figure 2 This is a flowchart of the first motor control process performed by the motor control device 10.

[0104] like Figure 2 As shown, when the first motor control process begins, the generation method change unit 30 investigates whether the change to the generation method performed by the generation method change unit 30 is valid (step S10). The generation method is the generation method by which the control unit 20 generates the drive signal. In other words, the generation method change unit 30 investigates whether its own operating mode is the first operating mode.

[0105] In step S10, if the change in the generation method performed by the generation method change unit 30 is valid (step S10: Yes), the correction value generation unit 31 generates a correction value based on the positional deviation between the target position indicated by the command signal and the detected target position indicated by the position sensor signal (step S20). This generation method is the same as the method used by the control unit 20 to generate the drive signal. In other words, when there is a positional deviation between the target position indicated by the command signal and the detected target position indicated by the position sensor signal, the correction value generation unit 31 generates a correction value to correct the command signal, thereby changing the target position by that positional deviation.

[0106] When the processing in step S20 ends, the correction unit 22 stores the generated correction value. If, during the processing in step S10, the change in the generation method performed by the generation method change unit 30 is not effective (step S10: No), the correction unit 22 maintains the stored correction value in its original state (step S30). The generation method is the same method used by the control unit 20 to generate the drive signal. Therefore, the correction unit 22 corrects the command signal based on the stored correction value and outputs the corrected command signal to the drive signal generation unit 21 (step S40).

[0107] Next, the calibration unit 22 investigates which of (A) to (C) is met: (A) whether the condition for resetting the stored calibration value is met; (B) whether the condition for resetting the calibration value is met in a way that makes the stored calibration value approach zero in stages and eventually become zero when the motor 50 is working; and (C) whether the condition for maintaining the stored calibration value is met. The condition for maintaining the stored calibration value is that neither the condition for resetting the stored calibration value nor the condition for resetting the calibration value in a way that makes the stored calibration value approach zero in stages and eventually become zero is met (step S50).

[0108] In the process of step S50, if the condition for resetting the stored correction value is met (step S50: A), the correction unit 22 resets the stored correction value (step S60).

[0109] In the process of step S50, if the condition is met that the stored correction value is gradually approached to zero and eventually becomes zero while the motor 50 is working (step S50: B), the correction unit 22 investigates whether the motor 50 is working (step S70).

[0110] In the process of step S70, if the motor 50 is not working (step S70: No), the correction unit 22 repeatedly performs the process of step S70 until the motor 50 becomes working.

[0111] In the process of step S70, when the motor 50 is working (step S70: Yes), the correction unit 22 resets the correction value according to the workload of the motor 50, so that the stored correction value gradually approaches zero and eventually becomes zero (step S80).

[0112] In the process of step S50, if the condition for holding the stored correction value is met (step S50: C), the correction unit 22 holds the stored correction value instead of resetting it (step S90).

[0113] When the processing of step S60, step S80, and step S90 is completed, the motor control device 10 ends the first motor control processing.

[0114] <Specific example>

[0115] The following describes a first specific working example, which is an example of the specific operation performed by the motor control device 10 configured as described above.

[0116] Figure 3 This is a schematic diagram showing a first specific example of operation of the motor control device 10.

[0117] The first specific working example illustrates the following situation: In sequence No. 1, although the controller 70 outputs a control command to move the target position of the movable part 60, which is intended by the controller 70, from the initial position 0 (zero) to the position 100, the detected target position, i.e., the actual target position, is the position 110. In sequence No. 2, although the controller 70 outputs a control command to move the target position of the movable part 60, which is intended by the controller 70, from the position 100 to the position 150, the change in the generation method performed by the generation method change unit 30 is effective. Therefore, a drive signal is generated to maintain the position of the movable part 60 at 110. The method is the method by which the control unit 20 generates the drive signal. In sequence No. 3, the switching unit 40 switches the change of the generation method performed by the generation method change unit 30 from valid to invalid, and resets the correction value of the correction unit 22 to zero. The generation method is the method by which the control unit 20 generates the drive signal. At the same time, the controller 70 continues to output a control command to move the target position of the movable part 60, which is imagined by the controller 70, from position 100 to position 150. In sequence No. 4, although the controller 70 outputs a control command to move the target position of the movable part 60, which is imagined by the controller 70, from position 150 to position 200, the detected target position is position 195.

[0118] Furthermore, in the first specific working example, the position sensor 61 is a camera device or a transmissive laser displacement sensor, which can detect the position of the object 65 within a range of ±20 based on the position of the position sensor 61 installed on the movable part 60.

[0119] like Figure 3As shown, in the first specific working example, in sequence No.1, firstly (0) the position of the movable part 60 is 0. Then (1) the switching unit 40 switches the change of the generation method performed by the generation method change unit 30 from invalid (hereinafter also referred to as "visual FB invalid") to valid (hereinafter also referred to as "visual FB valid"), the generation method being the generation method of the drive signal generated by the control unit 20.

[0120] At this time, since the position of object 65 is outside the detection range of position sensor 61, (2) position sensor 61 does not detect the position of object 65. Therefore, (3) the position deviation between the position of movable part 60 and the position of the detected target detected by position sensor 61 cannot be calculated. Therefore, (4) correction unit 22 maintains the initial value 0 (zero) correction value.

[0121] Next, (5) the controller 70 outputs a command signal that moves the target position of the movable part 60, as envisioned by the controller 70, from position 0 to position 100. Since the correction value held by the correction unit 22 is 0, (6) the correction unit does not correct the command signal, and outputs the original command signal as the corrected command signal to the drive signal generation unit 21. Accordingly, the drive signal generation unit 21 generates a drive signal by performing feedback control on the corrected command signal output from the correction unit 22, and drives the motor 50. This feedback control is the control that feeds back the encoder signal output from the encoder 51 to the corrected command signal. Thus, (7) the movable part 60 moves to the target position envisioned by the controller 70.

[0122] (7) When the position of the movable part 60 is 90, (8) the position of the object 65 is within the range that the position sensor 61 can detect. Therefore, the position sensor 61 detects the position of the object 65. (9) Here, the position sensor 61 detects the position of the movable part 60 as being 20 less than the target position. Since the position of the movable part 60 does not reach the target position and the target position of the movable part 60 as envisioned by the controller 70, (10) the position of the movable part 60 moves to 100 according to the command signal of the controller 70. (11) Here, the position sensor 61 detects the position of the movable part 60 as being 10 less than the target position. Although the position of the movable part 60 does not reach the target position, it reaches the target position of the movable part 60 as envisioned by the controller 70. Therefore, the correction value generation unit 31 generates a correction value 10 and outputs it to the correction unit 22. The correction value 10 is the position deviation between the target position and the target position of the movable part 60 as envisioned by the controller 70. Therefore, (12) the correction unit 22 maintains the correction value 10. Therefore, (13) the correction unit 22 outputs a corrected command signal to move the position of the movable part 60 toward the corrected target position 110. Accordingly, the drive signal generation unit 21 generates a drive signal by performing feedback control on the corrected command signal output from the correction unit 22, and drives the motor 50. The feedback control is the control that feeds back the encoder signal output from the encoder 51 to the corrected command signal. (14) Thus, the movable part 60 moves to position 110. (15) Therefore, the position deviation between the target position of the movable part 60 as envisioned by the corrected controller 70 and the position of the object 65 detected by the position sensor 61, i.e., the detected target position, is 0, that is, the position deviation from the actual target position is 0.

[0123] In sequence No. 2, firstly, (0) the position of the movable part 60 becomes 110. Next, (1) the switching unit 40 keeps the switching of the generation method performed by the generation method change unit 30 active, without switching, the generation method being the generation method in which the control unit 20 generates the drive signal. At this time, (2) the position of the object 65 is within the range that the position sensor 61 can detect. Therefore, (3) the position deviation between the corrected target position of the movable part 60 as envisioned by the controller 70 and the position of the object 65 detected by the position sensor 61, i.e., the detection target position, becomes 0. At this time, (4) the correction unit 22 maintains the correction value 10.

[0124] Next, (5) the controller 70 outputs a command signal to move the target position of the movable part 60, which is intended by the controller 70, from position 100 to position 150. However, since the correction value generation unit 31 wants to maintain the detected target position of the object 65, it generates a correction value of -40 and outputs it to the correction unit 22. Thus, (6) the correction unit 22 maintains the correction value of -40. In this way, (7) since the command signal output from the correction unit 22 is still 110, the position of the movable part 60 remains at 110.

[0125] In sequence No. 3, firstly, (0) the position of the movable part 60 becomes 110. Next, (1) the switching unit 40 switches the generation method change performed by the generation method change unit 30 from visual FB enabled to disabled. At this moment, the movable part 60 does not move. At this time, (2) the position sensor 61 does not detect the position of the object 65. Therefore, (3) the position deviation between the position of the movable part 60 and the position of the detected target detected by the position sensor 61 cannot be calculated. Therefore, (4) the correction unit 22 maintains the correction value -40. And, (5) the target position of the command signal at this moment becomes 150, and the target position of the corrected command signal at this moment becomes 110.

[0126] Next, the correction unit 22 resets the held correction value -40. Accordingly, (6) the correction unit 22 holds the correction value 0. Then, (7) the correction unit 22 outputs a corrected command signal to move the position of the movable part 60 toward the corrected target position 150. Accordingly, the drive signal generation unit 21 performs feedback control on the corrected command signal output from the correction unit 22 to generate a drive signal and drive the motor 50. The feedback control is the control that feeds back the encoder signal output from the encoder 51 to the corrected command signal. Thus, (8) the movable part 60 moves to position 150.

[0127] In sequence No. 4, firstly, (0) the position of the movable part 60 becomes 150. Next, (1) the switching unit 40 switches the generation method change performed by the generation method change unit 30 from visual FB invalid to valid. At this time, since the position of the object 65 is outside the detection range of the position sensor 61, (2) the position sensor 61 does not detect the position of the object 65. Therefore, (3) the position deviation between the position of the movable part 60 and the position of the detection target detected by the position sensor 61 cannot be calculated. Therefore, (4) the correction unit 22 maintains the initial value 0 (zero) as the correction value.

[0128] Next, (5) the controller 70 outputs a command signal to move the target position of the movable part 60, as envisioned by the controller 70, from position 150 to position 200. Since the correction unit 22 maintains a correction value of 0, (6) it does not correct the command signal, but instead outputs the original command signal as the corrected command signal to the drive signal generation unit 21. Accordingly, the drive signal generation unit 21 performs feedback control on the corrected command signal output from the correction unit 22 to generate a drive signal and drive the motor 50. This feedback control is the control that feeds back the encoder signal output from the encoder 51 to the corrected command signal. Thus, (7) the movable part 60 moves to the target position envisioned by the controller 70.

[0129] (7) If the position of the movable part 60 becomes 175, then (8) the position of the object 65 becomes within the range that the position sensor 61 can detect. Therefore, the position sensor 61 detects the position of the object 65. (9) Here, the position sensor 61 detects the position of the movable part 60 as being 20 less than the target position. Since the position of the movable part 60 does not reach the target position and the target position of the movable part 60 as envisioned by the controller 70, according to the command signal of the controller 70, (10) when the position of the movable part 60 moves to 195, (11) the position sensor 61 detects the position of the movable part 60 as the target position. Although the position of the movable part 60 reaches the target position, it does not reach the target position of the movable part 60 as envisioned by the controller 70. Therefore, the correction value generation unit 31 generates a correction value -5 and outputs it to the correction unit 22. The correction value -5 is the position deviation between the target position and the target position of the movable part 60 as envisioned by the controller 70. Therefore, (12) the correction unit 22 maintains the correction value -5. Therefore, (13) the correction unit 22 outputs a corrected command signal to move the position of the movable part 60 toward the corrected target position 195. Accordingly, the drive signal generation unit 21 performs feedback control on the corrected command signal output from the correction unit 22 to generate a drive signal and drive the motor 50. The feedback control is the control that feeds back the encoder signal output from the encoder 51 to the corrected command signal. In this way, the movable part 60 maintains the position 195. Therefore, the position deviation between the target position of the movable part 60 as envisioned by the corrected controller 70 and the position of the object 65 detected by the position sensor 61, i.e., the detected target position, remains 0, that is, the position deviation from the actual target position remains 0.

[0130] <Inspection>

[0131] As described above, by means of the motor control device 10 configured as described above, if the movable part 60 is moved to the target position indicated by the command signal, even if the position of the movable part 60 is different from the actual target position, the movable part 60 can be moved to the actual target position.

[0132] Thus, the motor control device 10 configured as described above provides a motor control device that can be further improved.

[0133] Furthermore, in sequence No. 3 of the first specific working example, the correction unit 22 moves the position of the movable part 60 from position 110 to position 150 so that the correction value can be reset in such a way that the correction value gradually approaches zero and eventually becomes zero while the motor 50 is working.

[0134] (Implementation Method 2)

[0135] The motor control system according to Embodiment 2 will be described below. The motor control system according to Embodiment 2 is constructed by modifying a part of the motor control system 1 according to Embodiment 1.

[0136] In the following description, the same components in the motor control system of Embodiment 2 that are the same as those in the motor control system 1 of Embodiment 1 will be given the same reference numerals and detailed descriptions will be omitted as they have already been described. The following description will focus on the differences between the two motor control systems.

[0137] Figure 4 This is a block diagram showing the configuration of the electric motor control system 1A according to Embodiment 2.

[0138] like Figure 4 As shown, the configuration of the motor control system 1A differs from that of the motor control system 1 in Embodiment 1, except that the motor control device 10 is replaced by the motor control device 10A. Furthermore, compared to the motor control device 10, the configuration of the motor control device 10A differs from that of the motor control device 10, except that the control unit 20 is replaced by the control unit 20A, and the generation method modification unit 30 is replaced by the generation method modification unit 30A. Also, compared to the control unit 20, the drive signal generation unit 21 is replaced by the drive signal generation unit 21A. Finally, compared to the generation method modification unit 30A, the configuration of the generation method modification unit 30A differs from that of the generation method modification unit 30, except that the correction value generation unit 31 is replaced by the correction value generation unit 31A, and a temporary stop unit 33 is added.

[0139] When a positional deviation occurs between the target position indicated by the command signal and the detected target position indicated by the position sensor signal, the temporary stop unit 33 outputs a motor stop signal to the drive signal generation unit 21A to stop the motor 50. Then, after a first predetermined time T1 has elapsed since the positional deviation occurred, the temporary stop unit 33 stops outputting the motor stop signal. Here, the first predetermined time T1 is preferably a period longer than the time from when the motor 50 is stopped until the vibration of the movable part 60 is suppressed.

[0140] In addition to the functions of the drive signal generation unit 21 described in Embodiment 1, the drive signal generation unit 21A further generates a motor control signal that stops the motor 50 during the period when the motor stop signal is output from the temporary stop unit 33, and outputs the generated motor control signal to the motor 50. Accordingly, the motor 50 stops from the point where the position deviation occurs until the first predetermined time T1 has elapsed.

[0141] When a positional deviation occurs between the target position and the position of the movable part 60 indicated by the position sensor signal, the correction value generation unit 31A stands still from the occurrence of the positional deviation until the first predetermined time T1 has elapsed. When the first predetermined time T1 has elapsed, and there is a positional deviation between the target position indicated by the command signal and the detected target position indicated by the position sensor signal, a correction value is generated to correct the command signal, and the generated correction value is output to the correction unit 22 so that the target position changes due to the positional deviation.

[0142] The correction value generated by the correction value generation unit 31A is output to the correction unit 22, thereby updating the correction value stored in the correction unit 22. Accordingly, the correction value generation unit 31A changes the method by which the control unit 20A generates the drive signal by generating the drive signal based on the encoder signal and the correction command value corrected by the updated correction value.

[0143] The correction value generation unit 31A can also output the generated correction value to the controller 70. Accordingly, the controller 70 can generate a command signal that reflects the correction value.

[0144] <Work>

[0145] The operation of the motor control device 10A configured as described above will now be explained.

[0146] The motor control device 10A performs a second motor control process, which is a modified version of a part of the first motor control process described in Embodiment 1.

[0147] Figure 5 This is a flowchart of the second motor control process performed by the motor control device 10A.

[0148] In the second motor control process, the processes in steps S110 and S120 to S190 are the same as those in steps S10 and S20 to S90 of the first motor control process according to Embodiment 1. In other words, the processes in steps S10 and S20 to S90 of the first motor control process are modified by renaming the control unit 20 as control unit 20A, the generation method modification unit 30 as generation method modification unit 30A, the correction value generation unit 31 as correction value generation unit 31A, and the drive signal generation unit 21 as drive signal generation unit 21A. Therefore, the explanation here will focus on the processes in steps S111 and S112.

[0149] In step S110, if the change in the generation method performed by the generation method change unit 30A is effective (step S110: Yes), the temporary stop unit 33 remains on standby until a positional deviation occurs between the target position indicated by the command signal and the detection target position indicated by the position sensor signal (step S111: No is repeated). The generation method is the method by which the control unit 20A generates a drive signal. When a positional deviation occurs between the target position indicated by the command signal and the detection target position indicated by the position sensor signal (step S111: Yes), a motor stop signal that stops the motor 50 is output to the drive signal generation unit 21A. Therefore, when a first predetermined time T1 has elapsed since the positional deviation occurred, the temporary stop unit 33 ends the output of the motor stop signal. Accordingly, the temporary stop unit 33 stops the motor 50 until the first predetermined time T1 has elapsed (step S112).

[0150] When the processing of step S112 ends, that is, when the first predetermined time T1 has elapsed after the motor 50 stops, the second motor control processing enters the processing of step S120.

[0151] <Inspection>

[0152] With the above configuration, when there is a positional deviation between the target position indicated by the command signal and the detected target position indicated by the position sensor signal, the motor control device 10A first temporarily stops the motor 50. Then, after a first predetermined time T1 has elapsed since the motor 50 temporarily stopped, a correction value is generated. The motor 50 is then driven according to the command signal corrected by the generated correction value.

[0153] Therefore, the motor control device 10A can generate a correction value only after a first predetermined time T1 has elapsed after the motor 50 has stopped, and after the vibration of the movable part 60 has been suppressed. Accordingly, the motor control device 10A can move the movable part 60 to the actual target position with higher precision.

[0154] With the above configuration, the motor control device 10A performs the following operation: when the position of the object 65 is within the detection range of the position sensor 61, the movement of the movable part 60 is temporarily stopped, and after the vibration of the movable part 60 is suppressed, the position of the movable part 60 is moved to the actual target position.

[0155] (Implementation Method 3)

[0156] The motor control system according to Embodiment 3 will be described below. The motor control system according to Embodiment 3 is constructed by modifying a part of the motor control system 1 according to Embodiment 1.

[0157] In the following description, the constituent elements of the motor control system in Embodiment 3 that are the same as those in the motor control system 1 in Embodiment 1 will be given the same reference numerals and detailed descriptions will be omitted as they have already been described. The following description will focus on the differences between the two motor control systems.

[0158] Figure 6 This is a block diagram showing the configuration of the electric motor control system 1C according to Embodiment 3.

[0159] like Figure 6 As shown, compared to the motor control system 1 of Embodiment 1, the motor control device 10 of the motor control system 1C is changed to the motor control device 10C, and an acceleration sensor 62 is added. Furthermore, compared to the motor control device 10, the generation method modification unit 30 of the motor control device 10C is changed to the generation method modification unit 30C. Moreover, compared to the generation method modification unit 30, the correction value generation unit 31 of the generation method modification unit 30C is changed to the correction value generation unit 31C, and the gain modification unit 32 is changed to the gain modification unit 32C.

[0160] An acceleration sensor 62 is installed on the movable part 60 to detect the acceleration of the movable part 60 and outputs an acceleration sensor signal showing the detected acceleration of the movable part 60 to the motor control device 10C.

[0161] The generation method modification unit 30C modifies the generation method of the drive signal generated by the control unit 20 based on the position sensor signal and the acceleration sensor signal.

[0162] When the acceleration of the movable part 60, as indicated by the acceleration sensor signal, is below a predetermined threshold and a second predetermined time T2 or more has elapsed, and there is a positional deviation between the target position indicated by the command signal and the position of the object 65, i.e., the detected target position, as indicated by the position sensor signal, the correction value generation unit 31C generates a correction value for correcting the command signal and outputs the generated correction value to the correction unit 22 so that the target position changes according to the positional deviation. Here, the second predetermined time T2 is preferably a time or more from when the acceleration of the movable part 60 falls below the predetermined threshold until the vibration of the movable part 60 is suppressed.

[0163] Accordingly, a correction value is generated only after the vibration of the movable part 60 is suppressed, after the acceleration of the movable part 60 has become fixed and a second predetermined time T2 has elapsed.

[0164] In addition, the second specified time T2 can also be 0.

[0165] The correction value generated by the correction value generation unit 31C is output to the correction unit 22, thereby updating the correction value stored in the correction unit 22. Accordingly, the correction value generation unit 31C changes the method by which the control unit 20 generates the drive signal by generating the drive signal based on the encoder signal and the correction command value corrected by the updated correction value.

[0166] The correction value generation unit 31C can also output the generated correction value to the controller 70. Accordingly, the controller 70 can generate a command signal that reflects the correction value.

[0167] The gain modification unit 32C modifies the gain parameter of the drive signal generation unit 21 based on the position sensor signal and / or the acceleration sensor signal, and this gain parameter is used to determine the gain of the drive signal for the command signal. Accordingly, the gain modification unit 32C modifies the method of generating the drive signal by the control unit 20 in order to generate the drive signal with the gain determined by the modified gain parameter. For example, the gain modification unit 32C may also modify the gain parameter of the drive signal generation unit 21 when the position deviation between the target position and the position of the movable part 60 indicated by the position sensor signal is greater than or equal to a predetermined value. Furthermore, the gain modification unit 32C may also modify the gain parameter of the drive signal generation unit 21 when, for example, the acceleration of the movable part 60 indicated by the acceleration sensor signal is greater than or equal to a predetermined value. Alternatively, the gain change unit 32C may change the gain parameter of the drive signal generation unit 21 when, for example, the position deviation between the target position and the position of the movable part 60 indicated by the position sensor signal is greater than or equal to a predetermined value, and the acceleration of the movable part 60 indicated by the acceleration sensor signal is greater than or equal to a predetermined value.

[0168] <Work>

[0169] The operation of the motor control device 10C described above will now be explained.

[0170] The motor control device 10C executes a third motor control process to control the motor 50 based on command signals, encoder signals, position sensor signals, and acceleration sensor signals. This third motor control process is a modified version of a part of the first motor control process described in Embodiment 1.

[0171] Figure 7 This is a flowchart of the third motor control process performed by the motor control device 10C.

[0172] In the third motor control process, the processes in steps S210 and S220 to S290 are the same as those in steps S10 and S20 to S90 in the first motor control process according to Embodiment 1. In other words, the generation method modification unit 30 is renamed generation method modification unit 30C and the correction value generation unit 31 is renamed correction value generation unit 31C, in relation to the processes in steps S10 and S20 to S90 of the first motor control process. Therefore, the explanation here will focus on the process in step S211.

[0173] In the process of step S210, if the change of the generation method performed by the generation method change unit 30 is effective (step S210: Yes), the correction value generation unit 31 stands by until the acceleration of the movable part 60 indicated by the acceleration sensor signal is below a predetermined threshold and until the second predetermined time T2 has elapsed (step S211: No is repeated). The generation method is the generation method of the drive signal generated by the control unit 20. When the acceleration of the movable part 60 indicated by the acceleration sensor signal is below the predetermined threshold and the second predetermined time T2 has elapsed (step S211: Yes), the third motor control process proceeds to the process of step S220.

[0174] <Inspection>

[0175] With the above configuration, the motor control device 10C also generates a correction value based on the acceleration of the movable part 60 indicated by the acceleration sensor signal. Then, the motor 50 is driven according to the command signal corrected by the generated correction value.

[0176] Therefore, with the electric motor control device 10C configured as described above, the movable part 60 can be moved to the actual target position with higher precision.

[0177] Furthermore, as described above, the correction value generation unit 31C generates the correction value only after a second predetermined time T2 has elapsed since the acceleration of the movable part 60 has become fixed, and after the vibration of the movable part 60 has been suppressed.

[0178] Therefore, with the electric motor control device 10C configured as described above, the movable part 60 can be moved to the actual target position with higher precision.

[0179] (Replenish)

[0180] As described above, examples of the technology disclosed in this application have been presented based on embodiments 1 to 3. However, this disclosure is not limited to these embodiments 1 to 3. Various modifications conceivable to those skilled in the art can be performed on these embodiments without departing from the spirit of this disclosure, as well as forms constructed by combining the constituent elements of different embodiments, may be included within the scope of one or more forms of this disclosure.

[0181] One embodiment of this disclosure is not only the motor control device 10 described above, but also a motor control method that executes the characteristic components included in the motor control device 10 as steps. Furthermore, one embodiment of this disclosure is a computer program that causes a computer to execute the characteristic steps included in the motor control method. Additionally, one embodiment of this disclosure is a computer-readable, non-transitory recording medium that records the aforementioned computer program.

[0182] This disclosure can be widely applied to systems for controlling electric motors, etc.

[0183] Symbol Explanation

[0184] 1. Motor control systems of 1A, 1B, and 1C

[0185] 10, 10A, 10C motor control devices

[0186] 20, 20A Control Unit

[0187] 21, 21A, 21B Drive Signal Generation Unit

[0188] 22 Correction Department

[0189] 30, 30A, 30C Generation Method Change Department

[0190] 31, 31A, 31C Correction value generation unit

[0191] 32, 32C Gain Variation Section

[0192] 33. Temporarily halted section

[0193] 40 Switching Unit

[0194] 50 electric motors

[0195] 51 encoder

[0196] 60 movable parts

[0197] 61 Position Sensor

[0198] 62 Accelerometer

[0199] 65. Objects

[0200] 70 Controller

Claims

1. An electric motor control device, comprising: The control unit generates a drive signal for driving the motor based on a command signal and an encoder signal, and outputs the generated drive signal to the motor. The command signal is used to position a movable part connected to the motor at a target position, and the encoder signal indicates the position of the motor detected by the encoder. The generation method modification unit modifies the generation method of the drive signal generated by the control unit based on the position sensor signal indicating the detected target position, wherein the detected target position is the position of the target position detected by the position sensor installed on the movable part. in, The position of the object detected by the position sensor is taken as the position of the detection target. The generation method modification unit, when there is a positional deviation between the target position and the detected target position, modifies the generation method as follows (1) to (3): (1) generates a correction value for correcting the command signal so that the target position changes according to the positional deviation; (2) outputs the generated correction value to the control unit; and (3) generates the drive signal based on the encoder signal and the command signal corrected by the correction value. The control unit includes: The calibration unit stores the calibration value, calibrates the command signal according to the command signal and the stored calibration value, and outputs the calibrated command signal. as well as The drive signal generation unit generates the drive signal by performing feedback control that feeds the encoder signal back to the calibrated command signal.

2. The motor control device as described in claim 1, The motor control device further includes a switching unit that switches the change to the generation method performed by the generation method change unit to be valid or invalid.

3. The motor control device as described in claim 1, The generation method modification unit further outputs the correction value to the controller that generates the instruction signal.

4. The motor control device as described in claim 1, If the first specified condition is met, the generation method modification unit resets the correction value.

5. The motor control device as described in claim 4, The first specified condition includes the condition that the electric motor is operating. The generation method modification unit resets the correction value in such a way that the correction value gradually approaches zero and eventually becomes zero while the motor is operating.

6. The motor control device as described in claim 1 or claim 2, The generation method modification unit modifies the gain parameter based on the position sensor signal and generates the drive signal accordingly, thereby modifying the generation method. The gain parameter is used to determine the gain of the drive signal for the command signal.

7. An electric motor control device, comprising: The control unit generates a drive signal for driving the motor based on a command signal and an encoder signal, and outputs the generated drive signal to the motor. The command signal is used to position a movable part connected to the motor at a target position, and the encoder signal indicates the position of the motor detected by the encoder. The generation method modification unit modifies the generation method of the drive signal generated by the control unit based on the position sensor signal indicating the detected target position, wherein the detected target position is the position of the target position detected by the position sensor installed on the movable part. in, The position of the object detected by the position sensor is taken as the position of the detection target. The generation method modification unit, when there is a positional deviation between the target position and the detected target position, modifies the generation method as follows (1) to (4): (1) temporarily stops the motor; (2) after a first predetermined time has elapsed since the motor was temporarily stopped, generates a correction value for correcting the command signal so that the target position changes according to the positional deviation; (3) outputs the generated correction value to the control unit; and (4) generates the drive signal based on the encoder signal and the command signal corrected by the correction value. The control unit includes: The calibration unit stores the calibration value, calibrates the command signal according to the command signal and the stored calibration value, and outputs the calibrated command signal. as well as The drive signal generation unit generates the drive signal by performing feedback control that feeds the encoder signal back to the calibrated command signal.

8. The motor control device as described in claim 7, The generation method modification unit further outputs the correction value to the controller that generates the instruction signal.

9. An electric motor control device, comprising: The control unit generates a drive signal for driving the motor based on a command signal and an encoder signal, and outputs the generated drive signal to the motor. The command signal is used to position a movable part connected to the motor at a target position, and the encoder signal indicates the position of the motor detected by the encoder. The generation method modification unit modifies the generation method of the drive signal generated by the control unit based on the position sensor signal indicating the detected target position, wherein the detected target position is the position of the target position detected by the position sensor installed on the movable part. in, The position of the object detected by the position sensor is taken as the position of the detection target. The generation method modification unit further modifies the generation method based on an acceleration sensor signal, the acceleration sensor signal indicating the acceleration of the movable part detected by an acceleration sensor installed on the movable part. When there is a positional deviation between the target position and the detected target position, and the acceleration of the movable part indicated by the acceleration sensor signal is below a predetermined threshold and more than a second predetermined time has elapsed, the generation method modification unit modifies the generation method as follows (1) to (3): (1) generates a correction value for correcting the command signal so that the target position changes according to the positional deviation; (2) outputs the generated correction value to the control unit; and (3) generates the drive signal based on the encoder signal and the command signal corrected by the correction value. The control unit includes: The calibration unit stores the calibration value, calibrates the command signal according to the command signal and the stored calibration value, and outputs the calibrated command signal. as well as The drive signal generation unit generates the drive signal by performing feedback control that feeds the encoder signal back to the calibrated command signal.

10. The motor control device as described in claim 9, The motor control device further includes a switching unit that switches the change to the generation method performed by the generation method change unit to be valid or invalid.

11. The electric motor control device as described in claim 9, If the second specified condition is met, the generation method modification unit resets the correction value.

12. The motor control device as described in claim 11, The second specified condition includes the condition that the electric motor is operating. The generation method modification unit resets the correction value in such a way that the absolute value of the correction value gradually approaches zero and eventually becomes zero when the motor is working.

13. The electric motor control device as described in claim 9, The generation method modification unit further outputs the correction value to the controller that generates the instruction signal.

14. The motor control device as described in claim 9 or claim 10, The generation method modification unit modifies the gain parameter and generates the drive signal based on the position sensor signal and / or the acceleration sensor signal, thereby modifying the generation method. The gain parameter is used to determine the gain of the drive signal for the command signal.

15. A method for controlling an electric motor, comprising the following steps: The control step involves generating a drive signal for driving the motor based on a command signal and an encoder signal, and outputting the generated drive signal to the motor. The command signal is used to position the movable part connected to the motor at a target position, and the encoder signal indicates the position of the motor detected by the encoder. The generation method modification step involves changing the generation method for generating the drive signal in the control step based on the position sensor signal indicating the detected target position. The detected target position is the position of the target position detected by the position sensor installed on the movable part. in, The position of the object detected by the position sensor is taken as the position of the detection target. In the generation method modification step, when there is a positional deviation between the target position and the detected target position, the generation method is modified as follows (1) to (3): (1) a correction value for correcting the command signal is generated so that the target position changes with the positional deviation; (2) the generated correction value is output; and (3) the drive signal is generated based on the encoder signal and the command signal corrected by the correction value. The control steps include: The calibration step includes storing the calibration value, calibrating the command signal based on the command signal and the stored calibration value, and outputting the calibrated command signal. The drive signal generation step generates the drive signal by performing feedback control that feeds the encoder signal back to the calibrated command signal.

16. A program recording medium having a program recorded thereon, the program being used to cause a motor control device controlling an electric motor to perform motor control processing. The motor control process includes the following steps: The control step involves generating a drive signal for driving the motor based on a command signal and an encoder signal, and outputting the generated drive signal to the motor. The command signal is used to position the movable part connected to the motor at a target position, and the encoder signal indicates the position of the motor detected by the encoder. The generation method modification step involves changing the generation method for generating the drive signal in the control step based on the position sensor signal indicating the detected target position. The detected target position is the position of the target position detected by the position sensor installed on the movable part. in, The position of the object detected by the position sensor is taken as the position of the detection target. In the generation method modification step, when there is a positional deviation between the target position and the detected target position, the generation method is modified as follows (1) to (3): (1) a correction value for correcting the command signal is generated so that the target position changes with the positional deviation; (2) the generated correction value is output; and (3) the drive signal is generated based on the encoder signal and the command signal corrected by the correction value. The control steps include: The calibration step includes storing the calibration value, calibrating the command signal based on the command signal and the stored calibration value, and outputting the calibrated command signal. The drive signal generation step generates the drive signal by performing feedback control that feeds the encoder signal back to the calibrated command signal.

Images