Motor Control Device

Abstract

A motor control device (300) is provided with: a feedforward controller (7) that generates a motor torque command and a motor position command; an encoder (4) that outputs a motor position detection value; a machine edge sensor (2) that detects a target object and outputs a measured value; a signal processor (11) that calculates the position of a moving body on the basis of the measured value and outputs a machine edge position detection value; and a feedback torque command generation unit (50) that generates a feedback torque command on the basis of the machine edge position detection value, the motor position detection value, and the motor position command. When the machine edge sensor cannot detect the positional relationship between the moving body and a target point, the feedback torque command generation unit generates the feedback torque command on the basis of the motor position detection value and the motor position command, and when the machine edge sensor can detect the positional relationship between the moving body and the target point, the feedback torque command generation unit generates the feedback torque command on the basis of the motor position detection value, the machine edge position detection value, the motor position command, and a signal obtained by adding a delay time to the motor position command.

Description

[Technical field]

[0001] The present disclosure relates to a motor control device that positions a moving body relative to a target point. [Background technology]

[0002] In manufacturing equipment for electronic devices and semiconductors, it is necessary to perform positioning in a short time with high accuracy by moving the movable body of the equipment to a target point and stopping it. For example, in equipment such as chip mounters and die bonders that mount electronic components and IC (Integrated Circuit) chips at target mounting positions on a board, the electronic components and IC chips held at the tip of the movable body are positioned at the target mounting positions on the board with high accuracy and mounted on the board. In this equipment, a mounting head equipped with a suction nozzle that picks up the electronic components and IC chips corresponds to the movable body, and the movable body moves within a predetermined range in the equipment by a rotary motor and a linear motion mechanism or a linear motor mechanism. The mounting head moves to an area where electronic components and IC chips are supplied and picks up the electronic components and IC chips with the suction nozzle, and then moves to the target mounting position on the board and releases the electronic components and IC chips from the suction nozzle to mount them on the board.

[0003] The positioning of the mounting head is performed by feedback control based on values ​​detected by an encoder that detects the rotational position of the motor used for movement or the position of the linear motor. In other words, feedback control is not performed by directly detecting the positional relationship between the suction nozzle of the mounting head or the electronic components, etc., picked up by the suction nozzle, and the target mounting position on the board.

[0004] In recent years, electronic components and IC chips have become increasingly miniaturized, and there is a demand for higher accuracy in positioning. However, the target mounting position on the board may differ for each individual board due to deviations or deformations in the board installation position. Therefore, if positioning is performed based only on the design values ​​of the board and the detection value signal of the encoder mentioned above, there is a possibility that the mounting position of the electronic component or IC chip may be misaligned with the specified position on the board.

[0005] In addition, in order to improve productivity, chip mounters and die bonders are required to not only improve positioning accuracy, but also to shorten the time it takes to pick up and release electronic components and IC chips. For example, the control device described in Patent Document 1 creates measurement data of the positional relationship between the control object and the target point by analyzing an image obtained by capturing an image of a range including the object of positioning control and the target point, and performs positioning using this measurement data and the encoder value of the motor. In image processing that analyzes an image to obtain measurement data, a certain amount of time is required from when the image is obtained to when the measurement data is obtained, and this time becomes dead time and hinders the realization of high-speed control. For this reason, when the control device described in Patent Document 1 cannot obtain the measurement data and the encoder value simultaneously, it calculates the latest positional deviation between the target point and the control object using data of the positional deviation between the target point and the control object that has been calculated in the past, the encoder value used in calculating this data, and the latest encoder value. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2019-3388 A Summary of the Invention [Problem to be solved by the invention]

[0007] The control device described in Patent Document 1 can achieve high-speed and high-precision positioning control. However, when disturbances with a period shorter than the dead time occur, an error occurs in the estimated value of the positional deviation between the target point and the controlled object, and the feedback control system using the estimated value may become unstable.

[0008] In addition, the detection of positional deviation using image processing has a problem that the detectable range is limited. For example, if a camera used for image acquisition can capture a range of 100 mm square with 1 μm per pixel, 10 billion pixels are required, and a very high performance camera and image processing are required. In the control device described in Patent Document 1, the required capture range is limited by capturing the target point with a fixed camera. However, in a chip mounter, it is necessary to position the chip mounter with respect to multiple target points on the board, and it is difficult for a fixed camera to handle multiple target points. For this reason, it is possible to mount a camera on a moving body and move the camera together with the moving body to capture multiple target points within the capture range. In such a configuration, the target point does not fall within the capture range until the moving body approaches the target point, so control using the detection result by image processing is not possible, and when the target point is outside the capture range, control is performed using only the detection result by the encoder. Then, after the moving body approaches the target point, it is necessary to switch to control using the detection result by image processing. When switching, the detection result by the encoder and the detection result by image processing may differ significantly due to the influence of dead time, and switching may cause the moving object to move in a sudden manner.

[0009] Similar issues also arise when using a sensor other than a camera to obtain the relative positional relationship between a target point and a moving object for control. For example, with a linear scale that can be installed at the tip of a machine to detect position, the scale installation position may be limited, and depending on the device, it may take time to obtain position information, resulting in similar issues. Similar issues also arise when using a laser displacement sensor.

[0010] The present disclosure has been made in consideration of the above, and has an object to provide a motor control device capable of performing positioning at high speed and with high accuracy. [Means for solving the problem]

[0011] In order to solve the above-mentioned problems and achieve the object, the present disclosure provides a motor control device that drives a motor based on a position command to move a moving body to a target point commanded by the position command, and includes a feedforward controller that generates a motor torque command and a motor position command based on the position command, an encoder that detects the position of the motor and outputs a motor position detection value signal indicative of the position, a machine end sensor that detects an object present within a certain range including the moving body and outputs a measurement value signal indicative of the detection result, a signal processor that calculates the position of the moving body with respect to the target point based on the measurement value signal and outputs a machine end position detection value signal indicative of the calculation result, a feedback torque command generation unit that generates a feedback torque command for correcting the motor torque command based on the machine end position detection value signal, the motor position detection value signal, and the motor position command, and a torque signal adder that adds the motor torque command and the feedback torque command to generate a torque command for the motor. The feedback torque command generation unit generates a feedback torque command based on the motor position detection value signal and the motor position command when in a first state in which the machine end sensor cannot detect the relative positional relationship between the moving body and the target point, and generates a feedback torque command based on the motor position detection value signal, the machine end position detection value signal, the motor position command, and a signal obtained by adding a delay time to the motor position command when in a second state in which the machine end sensor can detect the relative positional relationship between the moving body and the target point. Effect of the Invention

[0012] The motor control device according to the present disclosure advantageously provides high speed and high accuracy positioning. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is a block diagram showing a configuration example of a motor control device according to a first embodiment; [Diagram 2] FIG. 1 is a diagram illustrating an example of a relationship between a moving object and a machine end sensor of a motor control device according to a first embodiment. [Diagram 3]FIG. 1 is a diagram showing a configuration example in which a laser displacement meter is used as a machine end sensor of a motor control device according to a first embodiment; [Figure 4] FIG. 1 is a diagram showing a configuration example in which a machine end sensor of a motor control device according to a first embodiment is a linear scale; [Diagram 5] 1 is a flowchart showing an example of an operation of the motor control device according to the first embodiment. [Figure 6] FIG. 1 is a diagram showing an example of a control circuit that can be applied to realize a motor control device according to a first embodiment. [Figure 7] FIG. 11 is a block diagram showing a configuration example of a motor control device according to a second embodiment. [Figure 8] FIG. 11 is a block diagram showing a configuration example of a motor control device according to a third embodiment. [Figure 9] FIG. 13 is a block diagram showing a configuration example of a motor control device according to a fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, a motor control device according to an embodiment of the present disclosure will be described in detail with reference to the drawings.

[0015] Embodiment 1 Fig. 1 is a block diagram showing a configuration example of a motor control device 300 according to embodiment 1. The motor control device 300 shown in Fig. 1 is a device that performs positioning control to move a moving object 1 to a target point 100, which is a position commanded by the position command, by driving a motor 3 based on a position command.

[0016] In the motor control device 300 shown in FIG. 1, the moving object 1 is mechanically connected to the motor 3, and moves to a desired position, i.e., to a target point 100, by operating the motor 3. The machine end sensor 2 is installed so as to be able to detect an object existing within a certain range including the moving object 1, and detects the target point 100 if the target point 100 is included within this certain range. The encoder 4 detects the position of the motor 3, generates a signal indicating the position of the motor 3, and outputs it as a motor position detection value signal. The motor position detection value signal output by the encoder 4 is input to a position signal subtractor 6 via a detection value signal switcher 5. A position command for moving the moving object 1 to the target point 100 is input to an FF (Feed Forward) controller 7, which generates and outputs a motor position command and a motor torque command. The motor position command is input to the position signal subtractor 6 via a command value switcher 8. A position signal subtractor 6 calculates the difference between the output value of the command value switch 8 and the output value of the detection value signal switch 5 to generate a position error signal, and inputs the signal to an FB (Feedback) controller 9. The FB controller 9 calculates an FB torque command for correcting the position of the moving body 1 based on the position error signal. The FB torque command is input to a torque signal adder 10. The torque signal adder 10 corrects the motor torque command by adding the FB torque command to the motor torque command, and outputs the corrected motor torque command to the motor 3 as a torque command. The motor 3 generates torque according to the torque command output by the torque signal adder 10, and moves the moving body 1.

[0017] The machine end sensor 2 outputs a signal including information on the relative positional relationship between the moving object 1 and the target point 100 to the signal processor 11. When the target point 100 is included in the range detectable by the machine end sensor 2, that is, when the machine end sensor 2 is in a state where it can detect the target point 100, the signal output by the machine end sensor 2 includes information on the relative positional relationship between the moving object 1 and the target point 100. The signal processor 11 calculates the position of the moving object 1 based on the position of the target point 100 based on the information on the relative positional relationship between the moving object 1 and the target point 100 included in the output signal from the machine end sensor 2, and generates and outputs a machine end position detection value signal including information on the calculation result. When the signal output by the machine end sensor 2 does not include information on the relative positional relationship between the moving object 1 and the target point 100, the signal processor 11 may output a machine end position detection value signal that does not include the calculation result, or may not output a machine end position detection value signal. The machine end position detection value signal is input to adder 14 via first low-pass filter 12, which passes signals with a frequency below a set frequency. In addition, the motor position detection value signal output from encoder 4 is input to adder 14 via first high-pass filter 13, which passes signals with a frequency above a set frequency. Adder 14, which is the first adder of motor control device 300, adds the input signal from first low-pass filter 12 and the input signal from first high-pass filter 13, and outputs the addition result as a target point detection value signal. The target point detection value signal output by adder 14 is input to detection value signal switcher 5.

[0018] The motor position command output by the FF controller 7 is delayed by a predetermined time, i.e., a delay time is added by the motor position command delay unit 15, and then input to the adder 18 via the second low-pass filter 16 that passes signals with a predetermined frequency or less. The motor position command output by the FF controller 7 is also input to the adder 18 via the second high-pass filter 17 that passes signals with a predetermined frequency or more. The adder 18, which is the second adder of the motor control device 300, adds the input signal from the second low-pass filter 16 and the input signal from the second high-pass filter 17, and outputs the addition result as a target point command. The target point command output by the adder 18 is input to the command value switch 8.

[0019] The switch determiner 19 determines, based on the motor position detection value signal output by the encoder 4, which of the two signals input to the detection value signal switch 5 and the command value switch 8 is to be output.

[0020] In the motor control device 300, the detection value signal switch 5, the position signal subtractor 6, the command value switch 8, the FB controller 9, the first low-pass filter 12, the first high-pass filter 13, the adders 14, 18, the motor position command delay unit 15, the second low-pass filter 16, the second high-pass filter 17 and the switching determiner 19 constitute an FB torque command generation unit 50.

[0021] Next, the operation of the motor control device 300 shown in FIG. 1 will be described. The motor control device 300 includes a camera 200 as a machine end sensor 2 as shown in FIG. 2. FIG. 2 is a diagram showing an example of the relationship between the moving body 1 and the machine end sensor 2 of the motor control device 300 according to the first embodiment. In FIG. 2, an arrow indicates the direction in which the moving body 1 moves. In the example shown in FIG. 2, the camera 200, which is the machine end sensor 2, is attached to the moving body 1, and is configured to be able to capture the target point 100 when the moving body 1 approaches the target point 100. In addition, a mounting nozzle 101 capable of suctioning an electronic component 102 is attached to the moving body 1. There are also cases where an inspection device or the like is attached instead of the mounting nozzle 101. The motor control device 300 performs operations such as positioning the moving body 1 with respect to the target point 100, releasing the sucked electronic component 102 and placing it on the target point 100, and inspecting the target point 100 by contacting the inspection device attached instead of the mounting nozzle 101. Such work requires high precision, and it is necessary to position the electronic component 102 (or an inspection device) picked up by the mounting nozzle 101 with high precision relative to the target point 100, in other words, to position the moving body 1 with high precision relative to the target point 100.

[0022] As another configuration, there is a motor control device 300 in Fig. 3 and Fig. 4. In the motor control device 300 of the configuration example shown in Fig. 3, a laser displacement meter 201 is installed at a fixed position with respect to the target point 100, so that the position of the moving body 1 with respect to the target point 100 can be measured. In the example shown in Fig. 3, the laser displacement meter 201 corresponds to the machine end sensor 2 shown in Fig. 1. In the motor control device 300 of the configuration example shown in Fig. 4, a linear scale reading unit 202 is attached to the moving body 1, and a linear scale scale unit 203 is installed at a fixed position with respect to the target point 100, so that the position of the moving body 1 with respect to the target point 100 can be measured. In the example shown in Fig. 4, the linear scale reading unit 202 and the scale unit 203 correspond to the machine end sensor 2 shown in Fig. 1.

[0023] The driving source of the moving body 1 is the motor 3, and the moving body 1 moves when the motor 3 generates torque according to a motor torque command output by the FF controller 7. The FF controller 7 calculates the ideal torque that the motor 3 should output by a calculation equivalent to a second-order differential for a position command, which is a command signal for moving the moving body 1 to a target point 100, and outputs it as a motor torque command. In other words, the moving body 1 moves to the target point 100 based on the position command. However, even if the motor 3 generates torque according to the motor torque command, a tracking error occurs between the motor position, i.e., the position of the moving body 1, and the position command due to friction and other disturbances. Therefore, the encoder 4 detects the position of the motor 3 and outputs it as a motor position detection value signal, and further, the FF controller 7 calculates the ideal position to which the motor 3 should move from the position command and outputs it as a motor position command. A position error signal, which is the difference between the motor position detection value signal and this motor position command and represents the error between the position of the moving body 1 and the target point 100, is calculated by the position signal subtractor 6 and input to the FB controller 9. The FB controller 9 calculates an FB torque command so as to make the position error signal zero, and the motor 3 generates a torque according to this FB torque command. That is, the motor 3 generates a torque according to a torque command generated by the torque signal adder 10 adding the motor torque command calculated by the FF controller 7 and the FB torque command calculated by the FB controller 9, and moves the moving body 1 to follow the position command.

[0024] Here, if deformation of the machine or positional deviation of the target point 100 occurs, an error will occur between the moving body 1 and the target point 100 if the motor 3 is simply made to generate torque in response to the position command and the motor position detection value signal output by the encoder 4. Therefore, in the motor control device 300, the machine end sensor 2 detects the relative positional relationship between the target point 100 and the moving body 1, and outputs the detection result as a measurement value signal. Based on the measurement value signal output by the machine end sensor 2, the signal processor 11 calculates the position of the moving body 1 with respect to the position of the target point 100, and outputs the calculation result as a machine end position detection value signal. This process is explained as follows with reference to Figs. 2, 3, and 4 showing the configuration of the machine end sensor 2 provided in the motor control device 300.

[0025] In the case where the machine end sensor 2, the moving body 1, and the like are configured as shown in FIG. 2, the camera 200 captures an image of the target point 100 and sends the image to the signal processor 11 as a measurement value signal. The signal processor 11 detects the position of the target point 100 from the image input as the measurement value signal, calculates the position of the electronic component 102 with respect to the target point 100, and outputs the calculation result as a machine end position detection value signal. Note that since the relationship between the electronic component 102 and the moving body 1 is fixed, the signal processor 11 may generate and output a machine end position detection value signal representing the position of the moving body 1 with respect to the target point 100. In this case, the value of the position command input to the FF controller 7 is a value that takes into consideration the positional relationship between the moving body 1 and the electronic component 102 to be picked up by the mounting nozzle 101 provided on the moving body 1. In the following explanation, for simplicity, it is assumed that the machine end position detection value signal represents the position of the moving body 1.

[0026] 3, the position of the moving body 1 is measured by a laser displacement meter 201 located at a fixed position relative to the target point 100, and the laser displacement meter 201 sends a signal of the measurement result as a measurement value signal to the signal processor 11. The signal processor 11 calculates the position of the moving body 1 based on the target point 100 from the measured position of the moving body 1, and outputs the calculation result as a machine end position detection value signal.

[0027] 4, the position of the moving body 1 is measured by a linear scale reading unit 202 attached to the moving body 1 reading a linear scale scale unit 203 that is located at a fixed position relative to the target point 100, and the reading unit 202 sends the measurement result as a measurement value signal to the signal processor 11. The signal processor 11 calculates the position of the moving body 1 based on the target point 100 from the measured position of the moving body 1, and outputs the calculation result as a machine end position detection value signal.

[0028] In this embodiment, the machine end sensor 2 and the signal processor 11 are configured separately, but they may be integrated into one configuration. For example, the signal processor 11 may be included in the machine end sensor 2, that is, the machine end sensor 2 may calculate the position of the moving object 1 based on the target point 100 and output a machine end position detection value signal.

[0029] If the motor is operated so as to suppress the error occurring between the moving body 1 and the target point 100 using the machine end position detection value signal calculated in this manner, it is possible to suppress the error occurring between the moving body 1 and the target point 100. However, since the time required to transfer the measurement result of the machine end sensor 2 to the signal processor 11 and the time required for the signal processor 11 to process the signal and output the machine end position detection value signal are long, in other words, there is a large amount of dead time, so that performing high-response FB control using only the machine end position detection value signal will cause the FB control system to become unstable.

[0030] To deal with this, the motor control device 300 uses a first low-pass filter 12 that passes signals below a set frequency to extract only the low frequency components of the machine end position detection signal, and also uses a first high-pass filter 13 that passes signals above a set frequency to extract only the high frequency components from the motor position detection signal, which are used for FB control. The low frequency components of the machine end position detection signal and the high frequency components of the motor position detection signal are added by an adder 14, and the result is output as a target point detection signal. If the error between the moving body 1 and the target point 100 does not change in a vibrational manner, the error is represented by low frequency components, so information remains in the low frequency components of the machine end position detection signal. In addition, the effect of dead time at low frequencies in FB control is small, so that instability of FB control can be suppressed. And, since the high frequency components of the motor position detection signal are also used for FB control, highly responsive FB control can be realized.

[0031] In addition, when using the machine end sensor 2 as a sensor for positioning control, the problem is that the range in which the relative positional relationship between the target point 100 and the moving body 1 can be measured is limited. When the target point 100 or the moving body 1 moves and enters a range in which the relative positional relationship can be measured, the machine end sensor 2 outputs a measurement value signal including information on the relative positional relationship between the target point 100 and the moving body 1, and the signal processor 11 can calculate the position of the moving body 1 based on the position of the target point 100. Therefore, until the machine end sensor 2 can measure the relative positional relationship between the target point 100 and the moving body 1, control is performed using the motor position detection value signal, and when the relative positional relationship between the target point 100 and the moving body 1 can be obtained, control is switched to using the target point detection value signal. Specifically, in the motor control device 300, the detection value signal switch 5 switches the signal used for FB control. The switching decision device 19 makes a decision to switch, and determines from the motor position detection value signal whether the machine end sensor 2 can obtain the relative positional relationship between the target point 100 and the moving body 1, and instructs the detection value signal switcher 5 to switch signals according to the result of the decision. That is, the switching decision device 19 calculates the position of the moving body 1 based on the motor position detection value signal, and when it determines that the moving body 1 has approached the target point 100 to the extent that the machine end sensor 2 can obtain the relative positional relationship between the target point 100 and the moving body 1, it instructs the detection value signal switcher 5 to switch to outputting the target point detection value signal.

[0032] When the detection value signal switch 5 receives an instruction from the switch judging device 19 that judges that the moving body 1 has approached the target point 100 to such an extent that the machine end sensor 2 can obtain the relative positional relationship between the target point 100 and the moving body 1, the signal input to the position signal subtractor 6 is switched from the motor position detection value signal to the target point detection value signal. At this time, the position error signal input to the FB controller 9 may suddenly change, and the FB torque command output by the FB controller 9 may change significantly. A large change in the FB torque command must be suppressed because it may cause an impact on the moving body 1. Therefore, the motor control device 300 changes the motor position command, which is another input to the position signal subtractor 6, by the command value switch 8. This operation will be described below. The motor control device 300 adds a delay equivalent to the dead time from the measurement of the machine end sensor 2 until the signal processor 11 outputs the machine end position detection value signal to the motor position command by the motor position command delay device 15. Then, using the second low-pass filter 16 that passes signals below a set frequency, only the low frequency components of the motor position command to which a delay has been added are extracted. The frequency at this time is the same as that of the first low-pass filter 12, and the low frequency component signal of the motor position command to which a delay has been added by the motor position command delay unit 15 corresponds to the command signal for the low frequency component of the machine end position detection value signal. Also, using the second high-pass filter 17 that passes signals above a set frequency, only the high frequency components of the motor position command are extracted. The frequency at this time is the same as that of the first high-pass filter 13, and the high frequency component signal of the motor position command corresponds to the command signal for the high frequency component of the motor position detection value signal. Then, the two signals output by the second low-pass filter 16 and the second high-pass filter 17 are added by the adder 18, and output to the command value switch 8 as a target point command. This signal corresponds to the command signal for the target point detection value signal. Then, in accordance with the determination of the switching determiner 19, the command value switch 8 switches from the motor position command to the target point command and outputs it at the same time as the detection value signal switch 5 switches the signal.

[0033] That is, when the switching determinator 19 determines that the moving body 1 has approached the target point 100 to an extent that the machine end sensor 2 can obtain the relative positional relationship between the target point 100 and the moving body 1, it instructs the detection value signal switcher 5 and the command value switcher 8 to switch the signals to be output. Upon receiving an instruction from the switching determinator 19, the detection value signal switcher 5 changes its internal setting so as to output the target point detection value signal input from the adder 14, and the command value switcher 8, upon receiving an instruction from the switching determinator 19, changes its internal setting so as to output the target point command input from the adder 18.

[0034] By the switching decision unit 19 operating in this way to switch the signal output by the detection value signal switch 5 and the signal output by the command value switch 8, the position signal subtractor 6 calculates the error of the motor position detection value signal with respect to the motor position command when the machine end sensor 2 cannot measure the relative positional relationship between the target point 100 and the moving body 1, i.e., when the distance from the target point 100 to the moving body 1 is greater than a determined value, and inputs a position error signal that is the calculation result to the FB controller 9. On the other hand, when the machine end sensor 2 can measure the relative positional relationship between the target point 100 and the moving body 1, the position signal subtractor 6 calculates the error of the target point detection value signal with respect to the target point command, and inputs a position error signal that is the calculation result to the FB controller 9. The FB controller 9 calculates an FB torque command that corrects the position of the moving body 1 according to the position error signal input from the position signal subtractor 6.

[0035] The above-described operation of the motor control device 300 is shown in a flowchart in Fig. 5. Fig. 5 is a flowchart showing an example of the operation of the motor control device 300 according to the first embodiment.

[0036] The motor control device 300 first determines whether position detection by the machine end sensor 2 is possible, that is, whether the relative positional relationship between the target point 100 and the moving object 1 can be measured by the machine end sensor 2 (step S11). This determination is made by the switching determiner 19 based on the motor position detection value signal indicating the position of the motor 3 detected by the encoder 4.

[0037] If the relative positional relationship between the moving body 1 and the target point 100 cannot be measured by the machine end sensor 2 (step S11: No), the motor control device 300 generates a position error signal representing the error between the position of the moving body 1 and the target point 100 based on the motor position detection value signal (step S12). On the other hand, if the relative positional relationship between the target point 100 and the moving body 1 can be measured by the machine end sensor 2 (step S11: Yes), the motor control device 300 generates a position error signal based on the motor position detection value signal and the machine end position detection value signal representing the position of the moving body 1 with respect to the target point 100 (step S13).

[0038] After performing step S12 or step S13 to generate a position error signal, motor control device 300 corrects a motor torque command for motor 3 based on the position error signal to generate a torque command and control motor 3 (step S14).

[0039] The motor control device 300 causes the moving body 1 to approach the target point 100 by repeating the processes of steps S11 to S14.

[0040] As described above, in the motor control device 300 according to the present embodiment, before the relative positional relationship between the target point 100 and the moving body 1 can be measured by the machine end sensor 2, the FB controller 9 calculates an FB torque command to correct the position of the moving body 1 using the motor position detection value signal representing the position of the motor 3 detected by the encoder 4, and after the relative positional relationship between the target point 100 and the moving body 1 can be measured by the machine end sensor 2, the FB controller 9 calculates an FB torque command using the target point detection value signal calculated using the machine end position detection value signal representing the position of the moving body 1 based on the target point 100 detected based on the measurement value signal representing the measurement result by the machine end sensor 2 and the motor position detection value signal. This allows control so that the error between the moving body 1 and the target point 100 becomes zero. In addition, the motor position command and the target point command are switched and used for FB control in accordance with the switching between the motor position detection value signal and the target point detection value signal. This suppresses a sudden change in the input to the FB controller 9, and prevents a large change in the FB torque command due to signal switching. According to the motor control device 300 of this embodiment, even if a sensor with a long dead time in position detection or a limited detection range is used as the machine end sensor 2 to detect the positional deviation between the moving body 1 and the target point 100, it is possible to perform high-speed and high-precision positioning.

[0041] In this embodiment, the switching decision device 19 decides whether or not the relative positional relationship between the target point 100 and the moving body 1 can be measured by the machine end sensor 2 based on the motor position detection value signal, but the decision may also be made using a position command, a motor position command, or a machine end position detection value signal.

[0042] In addition, the switching decision device 19 decides whether or not the relative positional relationship between the target point 100 and the moving body 1 can be measured by the machine end sensor 2, and switches the signals output by the detection value signal switch 5 and the command value switch 8, but the switching may be performed at any timing as long as the relative positional relationship between the target point 100 and the moving body 1 can be measured by the machine end sensor 2. For example, the switching decision device 19 may compare the motor position detection value signal, the position command, the motor position command, or the machine end position detection value signal with a preset threshold value, and decide to switch when the distance from the moving body 1 to the target point 100 reaches a set value.

[0043] In addition, the frequencies of signals to be passed set by the first low-pass filter 12 and the second low-pass filter 16 are preferably the same, but may be different frequencies. Similarly, the frequencies of signals to be passed set by the first high-pass filter 13 and the second high-pass filter 17 are preferably the same, but may be different frequencies.

[0044] Next, the hardware configuration of the motor control device 300 will be described. As described above, the motor control device 300 is configured by appropriately combining arithmetic circuits such as an adder and a subtractor, filter circuits such as a high-pass filter and a low-pass filter, a switch, a delay device, an encoder, a camera, a laser displacement meter, and the like. In addition, the FF controller 7, the FB controller 9, the signal processor 11, and the switching determiner 19 are configured by a dedicated processing circuit or a general-purpose processor that executes a program. Examples of the dedicated processing circuit are an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), or a circuit that combines these. In addition, when the FF controller 7, the FB controller 9, the signal processor 11, and the switching determiner 19 are configured by a general-purpose processor, for example, a control circuit consisting of a processor 91 and a memory 92 shown in FIG. 6 is applied. FIG. 6 is a diagram showing an example of a control circuit that can be applied when realizing the motor control device 300 according to the first embodiment. The processor 91 is a CPU (also called a central processing unit, processing unit, arithmetic unit, microprocessor, microcomputer, or DSP (Digital Signal Processor)), a system LSI (Large Scale Integration), or the like. The memory 92 is a RAM (Random Access Memory), a ROM (Read Only Memory), an EPROM (Erasable Programmable Read Only Memory), an EEPROM (registered trademark), or the like. The memory 92 stores programs in which the functions of the FF controller 7, the FB controller 9, the signal processor 11, and the switching determiner 19 are described. The processor 91 operates as the FF controller 7, the FB controller 9, the signal processor 11, and the switching determiner 19 by executing the programs stored in the memory 92.It is also possible to configure some of the FF controller 7, FB controller 9, signal processor 11 and switching determiner 19 using dedicated processing circuits such as ASICs, with the remainder being configured using the control circuit shown in FIG.

[0045] Embodiment 2 FIG. 7 is a block diagram showing an example of a configuration of a motor control device 300a according to the second embodiment.

[0046] The motor control device 300a shown in FIG. 7 is different from the motor control device 300 according to the first embodiment shown in FIG. 1 in the configuration of the processing block that generates the position error signal that is the input signal to the FB controller 9. Specifically, the motor control device 300a is configured by replacing the detection value signal switcher 5, position signal subtracter 6, command value switcher 8, first low-pass filter 12, first high-pass filter 13, adder 14, second low-pass filter 16, second high-pass filter 17, adder 18, and switching determiner 19 of the motor control device 300 with a position signal subtracter 6a, first low-pass filter 12a, first high-pass filter 13a, adder 14a, second low-pass filter 16a, second high-pass filter 17a, adder 18a, switching determiner 19a, first switch 20, and second switch 21. The other components with the same reference numerals are the same as those in FIG. 1, and therefore will not be described.

[0047] In the motor control device 300a, the position signal subtractor 6a, the FB controller 9, the first low-pass filter 12a, the first high-pass filter 13a, the adders 14a, 18a, the motor position command delay unit 15, the second low-pass filter 16a, the second high-pass filter 17a, the switching determiner 19a, the first switch 20 and the second switch 21 constitute an FB torque command generating unit 50a.

[0048] Next, the operation of the motor control device 300a shown in FIG. 7 will be described. The first switch 20 receives the motor position detection signal and the machine end position detection signal. The first switch 20 outputs one of these two input signals. The first low-pass filter 12a passes signals with a frequency equal to or lower than a predetermined frequency from the output of the first switch 20 and inputs the signals to the adder 14a. The first high-pass filter 13a passes signals with a frequency equal to or higher than a predetermined frequency from the motor position detection signal and inputs the signals to the adder 14a. The adder 14a adds the two input signals to generate and output the FB position detection signal. The switch determiner 19a determines whether the first switch 20 outputs the motor position detection signal or the machine end position detection signal based on the motor position detection signal. Here, the first low-pass filter 12a and the first high-pass filter 13a are set so that, when the first switch 20 outputs the motor position detection value signal, the result of adding the motor position detection value signal that has passed through the first low-pass filter 12a and the motor position detection value signal that has passed through the first high-pass filter 13a is the same as the motor position detection value signal immediately after being output from the encoder 4. In this manner, the adder 14a outputs the motor position detection value signal as the FB position detection value signal when the machine end sensor 2 is in a state where it cannot measure the relative positional relationship between the target point 100 and the moving body 1, and can output a signal equivalent to the target point detection value signal described in the first embodiment as the FB position detection value signal when the machine end sensor 2 is in a state where it can measure the relative positional relationship between the target point 100 and the moving body 1.

[0049] The second switch 21 receives the motor position command and the motor position command with a delay added thereto, output by the motor position command delay unit 15. The second switch 21 outputs one of these two input signals. The second low-pass filter 16a passes signals with a frequency equal to or lower than a predetermined frequency from the output of the second switch 21 and inputs the passed signals to the adder 18a. The second high-pass filter 17a passes signals with a frequency equal to or higher than a predetermined frequency from the motor position command and inputs the passed signals to the adder 18a. The adder 18a adds the two input signals to generate and output an FF position command. The switching decision unit 19a controls the second switch 21 to switch the signal output at the same timing as the signal output by the first switch 20, based on the motor position detection value signal. Specifically, the switching decision unit 19a controls the first switch 20 and the second switch 21 so that the output of the second switch 21 switches from the motor position command to a motor position command with a delay added at the same time that the output of the first switch 20 switches from the motor position detection value signal to the machine end position detection value signal. Here, when the second switch 21 outputs the motor position command, the second low-pass filter 16a and the second high-pass filter 17a are set so that the result of adding the motor position detection value signal that has passed through the second low-pass filter 16a and the motor position command that has passed through the second high-pass filter 17a is the same as the motor position command immediately after being output from the FF controller 7. By doing this, when the machine end sensor 2 is in a state where it cannot measure the relative positional relationship between the target point 100 and the moving body 1, the adder 18a outputs a motor position command as an FF position command, and when the machine end sensor 2 is in a state where it can measure the relative positional relationship between the target point 100 and the moving body 1, the adder 18a can output a signal equivalent to the target point command described in embodiment 1 as an FF position command.

[0050] The position signal subtractor 6a calculates the difference between the FB position detection value signal and the FF position command to generate a position error signal and inputs it to the FB controller 9. The FB controller 9 calculates an FB torque command for correcting the position of the moving body 1 based on the position error signal.

[0051] As described above, in the motor control device 300a according to this embodiment, before the relative positional relationship between the target point 100 and the moving body 1 can be measured by the machine end sensor 2, the FB controller 9 calculates the FB torque command to correct the position of the moving body 1 using the FB position detection value signal corresponding to the motor position detection value signal indicating the position of the motor 3 detected by the encoder 4, and after the relative positional relationship between the target point 100 and the moving body 1 can be measured by the machine end sensor 2, the FB controller 9 calculates the FB torque command using the FB position detection value signal corresponding to the target point detection value signal described in the first embodiment, which can be calculated from the machine end position detection value signal and the motor position detection value signal. This makes it possible to control so that the error between the moving body 1 and the target point 100 becomes zero. In addition, the switching judger 19a controls the first switch 20 and the second switch 21 so that the timing at which the signal output by the adder 14a as the FB position detection value signal is switched is the same as the timing at which the signal output by the adder 18a as the FF position command is switched. This suppresses sudden changes in the input to the FB controller 9, and prevents a large change in the FB torque command due to signal switching, thereby realizing stable positioning control. In addition, the output of the first switch 20 passes through the first low-pass filter 12a, and the output of the second switch 21 passes through the second low-pass filter 16a, thereby suppressing sudden changes in values ​​that may occur due to switching, and realizing stable positioning control.

[0052] In this embodiment, the switching judger 19a judges whether or not the relative positional relationship between the target point 100 and the moving body 1 can be measured by the machine end sensor 2 based on the motor position detection value signal, but the judgment may also be made using a position command, a motor position command, or a machine end position detection value signal.

[0053] In addition, the switching determinator 19a determines whether or not the relative positional relationship between the target point 100 and the moving body 1 can be measured by the machine end sensor 2, and switches the signals output by the first switch 20 and the second switch 21, but the switching may be performed at any timing as long as the relative positional relationship between the target point 100 and the moving body 1 can be measured by the machine end sensor 2. For example, the switching determinator 19a may compare the motor position detection value signal, the position command, the motor position command, or the machine end position detection value signal with a preset threshold value, and determine to switch when the distance from the moving body 1 to the target point 100 reaches a predetermined value.

[0054] In addition, the frequencies of the signals to be passed set by the first low-pass filter 12a and the second low-pass filter 16a are preferably the same, but may be different frequencies. Similarly, the frequencies of the signals to be passed set by the first high-pass filter 13a and the second high-pass filter 17a are preferably the same, but may be different frequencies.

[0055] Embodiment 3 FIG. 8 is a block diagram showing an example of a configuration of a motor control device 300b according to the third embodiment.

[0056] A motor control device 300b shown in Fig. 8 is different from the motor control device 300a according to the second embodiment shown in Fig. 7 in the configuration of a processing block that generates a position error signal that is an input signal to the FB controller 9. Specifically, the motor control device 300b replaces the second low-pass filter 16a, the switching determinator 19a, and the first switch 20 of the motor control device 300a with a second low-pass filter 16b, a switching determinator 19b, and a switch 20b, adds a motor position detection value delay unit 22, and omits the second switch 21. The other components with the same reference numerals are the same as those in Fig. 7, and therefore will not be described.

[0057] In the motor control device 300b, the position signal subtractor 6a, the FB controller 9, the first low-pass filter 12a, the first high-pass filter 13a, the adders 14a, 18a, the motor position command delay unit 15, the second low-pass filter 16b, the second high-pass filter 17a, the switching decision unit 19b, the switch 20b and the motor position detection value delay unit 22 constitute an FB torque command generation unit 50b.

[0058] Next, the operation of the motor control device 300b shown in FIG. 8 will be described. The motor position detection value delay unit 22 adds a predetermined time delay to the motor position detection value signal input from the encoder 4 and outputs the signal to the switcher 20b. The motor position detection value delay unit 22 adds a time delay based on the dead time corresponding to the time required from the measurement by the machine end sensor 2 to the output of the machine end position detection value signal by the signal processor 11 to the motor position detection value signal, thereby making it possible to give the motor position detection value signal a dead time equivalent to that of the machine end position detection value signal. The first low-pass filter 12a passes signals with a frequency equal to or lower than a predetermined frequency for the output of the switcher 20b, and inputs the signals to the adder 14a. The first high-pass filter 13a passes signals with a frequency equal to or higher than a predetermined frequency for the motor position detection value signal, and inputs the signals to the adder 14a. The adder 14a adds the two input signals to generate the FB position detection value signal and outputs it. Based on the motor position detection value signal, the switching decision device 19b decides whether to output from the switch 20b the motor position detection value signal to which a time delay has been added by the motor position detection value delay device 22, or the machine end position detection value signal.

[0059] The second low-pass filter 16b passes signals with a frequency equal to or lower than a predetermined frequency for the motor position command to which a time delay has been added by the motor position command delay unit 15, and inputs the signals to the adder 18a. The second high-pass filter 17a passes signals with a frequency equal to or higher than a predetermined frequency for the motor position command, and inputs the signals to the adder 18a. The adder 18a adds the two input signals to generate and output an FF position command.

[0060] The position signal subtractor 6a calculates the difference between the FB position detection value signal and the FF position command to generate a position error signal and inputs it to the FB controller 9. The FB controller 9 calculates an FB torque command for correcting the position of the moving body 1 based on the position error signal.

[0061] Here, the value that has passed through the first low-pass filter 12a and the value that has passed through the second low-pass filter 16b have a dead time or a time delay of the same length as the dead time. Therefore, it is possible to control so that the high frequency component of the motor position detection value signal follows the high frequency component of the FF position command, and the low frequency component of the motor position detection value signal or the machine end position detection value signal with a delay added follows the low frequency component of the FF position command. When the machine end sensor 2 cannot measure the relative positional relationship between the target point 100 and the moving body 1, the switching decision unit 19b switches the setting of the switch 20b so that a value calculated from only the motor position detection value signal is output from the adder 14a as the FB position detection value signal, and when the machine end sensor 2 can measure the relative positional relationship between the target point 100 and the moving body 1, a value calculated from the motor position detection value signal and the machine end position detection value signal is output from the adder 14a as the FB position detection value signal. This allows the motor control device 300b to perform control so that the error between the moving body 1 and the target point 100 becomes zero.

[0062] As described above, in the motor control device 300b according to this embodiment, before the relative positional relationship between the target point 100 and the moving body 1 can be measured by the machine end sensor 2, the FB controller 9 calculates an FB torque command to correct the position of the moving body 1 using the motor position detection value signal representing the position of the motor 3 detected by the encoder 4, and after the relative positional relationship between the target point 100 and the moving body 1 can be measured by the machine end sensor 2, the FB controller 9 calculates an FB torque command using the FB position detection value signal calculated from the machine end position detection value signal and the motor position detection value signal. This makes it possible to control so that the error between the moving body 1 and the target point 100 is zero. In addition, by eliminating the switching of the FF position command regardless of the FB position detection value signal, the control system can be simplified. In addition, by giving the motor position detection value signal input to the switch 20b a time delay equivalent to the dead time of the machine end position detection value signal and having the output of the switch 20b pass through the first low-pass filter 12a, it is possible to suppress sudden changes in value that may occur when the output signal is switched by the switch 20b, and stable positioning control can be achieved.

[0063] In this embodiment, the switching judger 19b judges whether or not the relative positional relationship between the target point 100 and the moving body 1 can be measured by the machine end sensor 2 based on the motor position detection value signal, but the judgment may also be made using a position command, a motor position command, or a machine end position detection value signal.

[0064] In addition, the switching determinator 19b determines whether or not the relative positional relationship between the target point 100 and the moving body 1 can be measured by the machine end sensor 2, and switches the signal output by the switch 20b, but the switching may be performed at any timing as long as the relative positional relationship between the target point 100 and the moving body 1 can be measured by the machine end sensor 2. For example, the switching determinator 19b may compare the motor position detection value signal, the position command, the motor position command, or the machine end position detection value signal with a preset threshold value, and determine to switch when the distance from the moving body 1 to the target point 100 reaches a specified value.

[0065] In addition, the frequencies of the signals to be passed set by the first low-pass filter 12a and the second low-pass filter 16b are preferably the same, but may be different. Similarly, the frequencies of the signals to be passed set by the first high-pass filter 13a and the second high-pass filter 17a are preferably the same, but may be different.

[0066] Embodiment 4 FIG. 9 is a block diagram showing an example of a configuration of a motor control device 300c according to the fourth embodiment. As shown in FIG.

[0067] A motor control device 300c shown in Fig. 9 is different from the motor control device 300b according to the third embodiment shown in Fig. 8 in the configuration of a processing block that generates a position error signal that is an input signal to the FB controller 9. Specifically, the motor control device 300c replaces the position signal subtractor 6a, first low-pass filter 12a, adder 14a, and adder 18a of the motor control device 300b with a position signal subtractor 6c, first low-pass filter 12c, adder 14c, and adder 18c, and omits the switch 20b, switch determiner 19b, and motor position detection value delay unit 22. Other components with the same reference numerals are the same as those in Fig. 8, and therefore will not be described.

[0068] In the motor control device 300c, the position signal subtractor 6c, the FB controller 9, the first low-pass filter 12c, the first high-pass filter 13a, the adders 14c, 18c, the motor position command delay unit 15, the second low-pass filter 16b and the second high-pass filter 17a constitute an FB torque command generation unit 50c.

[0069] Next, the operation of the motor control device 300c shown in Fig. 9 will be described. The first low-pass filter 12c passes signals with a frequency equal to or lower than a set frequency for the machine end position detection value signal, and inputs the signals to the adder 14c. The first high-pass filter 13a passes signals with a frequency equal to or higher than a set frequency for the motor position detection value signal, and inputs the signals to the adder 14c. The adder 14c adds the two input signals to generate and output a target point detection value signal.

[0070] The second low-pass filter 16b passes signals with a frequency equal to or lower than a predetermined frequency for the motor position command to which a time delay has been added by the motor position command delay unit 15, and inputs the signals to the adder 18c. The second high-pass filter 17a passes signals with a frequency equal to or higher than a predetermined frequency for the motor position command, and inputs the signals to the adder 18c. The adder 18c adds the two input signals to generate and output a target point command.

[0071] The position signal subtractor 6c calculates the difference between the target point command and the target point detection value signal to generate a position error signal and inputs it to the FB controller 9. The FB controller 9 calculates an FB torque command for correcting the position of the moving body 1 based on the position error signal.

[0072] Here, the machine end position detection signal that has passed through the first low-pass filter 12c has a dead time, and a time delay of the same length as the dead time of the machine end position detection signal is added to the motor position command that has passed through the second low-pass filter 16b. Therefore, the FB controller 9 calculates the FB torque command so that the high frequency components of the motor position detection signal follow the high frequency components of the target point command, and so that the low frequency components of the machine end position detection signal follow the low frequency components of the target point command, thereby making it possible to control the error between the moving body 1 and the target point 100 to be zero.

[0073] As described above, in the motor control device 300c according to this embodiment, the FB controller 9 calculates the FB torque command using the target point detection signal calculated based on the machine end position detection signal indicating the position of the moving body 1 with respect to the target point 100 based on the measurement value signal output by the machine end sensor 2 and the motor position detection signal. This allows control so that the error between the moving body 1 and the target point 100 becomes zero. This configuration is useful when the relative positional relationship between the target point 100 and the moving body 1 can be measured by the machine end sensor 2, and the control system can be simplified by eliminating the switching of values ​​used in the calculation of the signal used for FB control and the signal used for FF control. In addition, since the values ​​used for calculation are not switched, it is possible to suppress a sudden change in values ​​that may occur when signals are switched, and stable positioning control can be realized.

[0074] It is preferable that the frequencies of the signals to be passed through the first low-pass filter 12c and the second low-pass filter 16b are the same, but they may be different frequencies.

[0075] The configurations shown in the above embodiments are merely examples, and may be combined with other known technologies, or the embodiments may be combined with each other. Also, parts of the configurations may be omitted or modified without departing from the spirit of the invention. [Explanation of symbols]

[0076] REFERENCE SIGNS LIST 1 moving body, 2 machine end sensor, 3 motor, 4 encoder, 5 detection value signal switch, 6, 6a, 6c position signal subtractor, 7 FF controller, 8 command value switch, 9 FB controller, 10 torque signal adder, 11 signal processor, 12, 12a, 12c first low-pass filter, 13, 13a first high-pass filter, 14, 14a, 14c, 18, 18a, 18c adder, 15 motor position command delay device, 16, 16a, 16b second low-pass filter, 17, 17a second high-pass filter, 19, 19a, 19b switch determination device, 20 first switch, 20b switch, 21 second switch, 22 motor position detection value delay device, 50, 50a, 50b, 50c FB torque command generation unit, 100 Target point, 101 mounting nozzle, 102 electronic component, 200 camera, 201 laser displacement meter, 202 reading unit, 203 scale unit, 300, 300a, 300b, 300c motor control device.

Claims

1. A motor control device that drives a motor based on a position command to move a moving body to a target point specified by the position command, a feedforward controller that generates a motor torque command and a motor position command based on the position command; an encoder for detecting a position of the motor and outputting a motor position detection value signal indicative of the position; a machine end sensor that detects an object present within a certain range including the moving body and outputs a measurement value signal indicative of the detection result; a signal processor that calculates a position of the moving body with respect to the target point based on the measurement value signal and outputs a machine end position detection value signal indicative of the calculation result; a feedback torque command generating unit that generates a feedback torque command for correcting the motor torque command based on the machine end position detection value signal, the motor position detection value signal, and the motor position command; a torque signal adder that adds the motor torque command and the feedback torque command to generate a torque command for the motor; Equipped with the feedback torque command generating unit generates the feedback torque command based on the motor position detection value signal and the motor position command when the machine end sensor is in a first state in which it cannot detect the relative positional relationship between the moving body and the target point, and generates the feedback torque command based on the motor position detection value signal, the machine end position detection value signal, the motor position command, and a signal obtained by adding a delay time to the motor position command when the machine end sensor is in a second state in which it can detect the relative positional relationship between the moving body and the target point. A motor control device comprising:

2. The feedback torque command generating unit a first low-pass filter that passes signal components of the machine end position detection value signal having a frequency equal to or lower than a predetermined frequency; a first high-pass filter that passes signal components of the motor position detection value signal having a frequency equal to or higher than a predetermined frequency; a first adder that adds an output of the first low-pass filter and an output of the first high-pass filter; a motor position command delay unit that adds the delay time to the motor position command and outputs the motor position command; a second low-pass filter that passes signal components of the signal output from the motor position command delay unit that have a frequency equal to or lower than a predetermined frequency; a second high-pass filter that passes signal components of the motor position command having a frequency equal to or higher than a predetermined frequency; a second adder that adds an output of the second low-pass filter and an output of the second high-pass filter; a detection value signal switch which receives the motor position detection value signal and the output signal of the first adder, and outputs the motor position detection value signal when in the first state, and outputs the signal input from the first adder when in the second state; a command value switch that receives the motor position command and the output signal of the second adder, and outputs the motor position command when in the first state, and outputs the signal input from the second adder when in the second state; a feedback controller that calculates the feedback torque command based on a difference between an output of the detection value signal switch and an output of the command value switch; The motor control device according to claim 1 , further comprising:

3. a switching determiner that determines whether the state is the first state or the second state based on the motor position detection value signal, the machine end position detection value signal, the position command, or the motor position command, and controls the detection value signal switch and the command value switch based on a result of the determination; The motor control device according to claim 2 , further comprising:

4. The feedback torque command generating unit a first switch which receives the motor position detection value signal and the machine end position detection value signal, and outputs the motor position detection value signal in the first state, and outputs the machine end position detection value signal in the second state; a first low-pass filter that passes signal components of the signal output from the first switch that have a frequency equal to or lower than a predetermined frequency; a first high-pass filter that passes signal components of the motor position detection value signal having a frequency equal to or higher than a predetermined frequency; a first adder that adds an output of the first low-pass filter and an output of the first high-pass filter; a motor position command delay unit that adds the delay time to the motor position command and outputs the motor position command; a second switch that receives the motor position command and an output signal from the motor position command delay unit, and outputs the motor position command in the first state and outputs the signal input from the motor position command delay unit in the second state; a second low-pass filter that passes signal components of the signal output by the second switch that have a frequency equal to or lower than a predetermined frequency; a second high-pass filter that passes signal components of the motor position command having a frequency equal to or higher than a predetermined frequency; a second adder that adds an output of the second low-pass filter and an output of the second high-pass filter; a feedback controller that calculates the feedback torque command based on a difference between an output of the first adder and an output of the second adder; The motor control device according to claim 1 , further comprising:

5. a switching determiner that determines whether the state is the first state or the second state based on the motor position detection value signal, the machine end position detection value signal, the position command, or the motor position command, and controls the first switch and the second switch based on the determination result; The motor control device according to claim 4 , further comprising:

6. The feedback torque command generating unit a motor position detection value delay unit that adds a delay time to the motor position detection value signal and outputs the signal; a switch to which an output signal of the motor position detection value delay device and the machine end position detection value signal are input, the switch outputting the signal inputted from the motor position detection value delay device in the first state, and outputting the machine end position detection value signal in the second state; a first low-pass filter that passes signal components of the signal output by the switch that have a frequency equal to or lower than a predetermined frequency; a first high-pass filter that passes signal components of the motor position detection value signal having a frequency equal to or higher than a predetermined frequency; a first adder that adds an output of the first low-pass filter and an output of the first high-pass filter; a motor position command delay unit that adds the delay time to the motor position command and outputs the motor position command; a second low-pass filter that passes signal components of the signal output from the motor position command delay unit that have a frequency equal to or lower than a predetermined frequency; a second high-pass filter that passes signal components of the motor position command having a frequency equal to or higher than a predetermined frequency; a second adder that adds an output of the second low-pass filter and an output of the second high-pass filter; a feedback controller that calculates the feedback torque command based on a difference between an output of the first adder and an output of the second adder; The motor control device according to claim 1 , further comprising:

7. a switching determiner that determines whether the state is the first state or the second state based on the motor position detection value signal, the machine end position detection value signal, the position command, or the motor position command, and controls the switch based on the determination result; The motor control device according to claim 6, further comprising:

8. The feedback torque command generating unit a first low-pass filter that passes signal components of the machine end position detection value signal having a frequency equal to or lower than a predetermined frequency; a first high-pass filter that passes signal components of the motor position detection value signal having a frequency equal to or higher than a predetermined frequency; a first adder that adds an output of the first low-pass filter and an output of the first high-pass filter; a motor position command delay unit that adds the delay time to the motor position command and outputs the motor position command; a second low-pass filter that passes signal components of the signal output from the motor position command delay unit that have a frequency equal to or lower than a predetermined frequency; a second high-pass filter that passes signal components of the motor position command having a frequency equal to or higher than a predetermined frequency; a second adder that adds an output of the second low-pass filter and an output of the second high-pass filter; a feedback controller that calculates the feedback torque command based on a difference between an output of the first adder and an output of the second adder; The motor control device according to claim 1 , further comprising:

9. the delay time added by the motor position detection value delay device to the motor position detection value signal is set to a time equivalent to a dead time which is the sum of a time required from when the machine end sensor detects an object present within the certain range until when it outputs the measurement value signal, and a time required from when the measurement value signal is input to the signal processor until when it outputs the machine end position detection value signal, 8. The motor control device according to claim 6, wherein the first and second motor control devices are arranged in a first and second positions.

10. the delay time added by the motor position command delay unit to the motor position command is set to a time equivalent to a dead time which is the sum of a time required from when the machine end sensor detects an object present within the certain range until it outputs the measurement value signal, and a time required from when the measurement value signal is input to the signal processor until it outputs the machine end position detection value signal, 9. The motor control device according to claim 2, 4, 6 or 8.

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