Characteristic calculation device, characteristic calculation method, and program recording medium

Abstract

The characteristic calculation device (10) is provided with: a sensor information acquisition section (20) that acquires position information and acceleration information, wherein the position information indicates a position of a motor (70) detected by a position detector (71), and the acceleration information indicates an acceleration of a movable section (80) detected by an acceleration sensor (81) mounted to the movable section (80) connected to the motor (70); and a sensor characteristic calculation section (30) that calculates at least one of balance degree information and detection sensitivity information based on the position information and the acceleration information, and outputs at least one of the calculated balance degree information and the detection sensitivity information, wherein the balance degree information indicates a degree of coincidence of a detection axis direction of the acceleration sensor (81) with a direction of an acceleration that the acceleration sensor (81) should detect, and the detection sensitivity information indicates a detection sensitivity of the acceleration sensor (81).

Description

Technical Field

[0001] This disclosure relates to a characteristic calculation device for calculating the characteristics of an acceleration sensor mounted on a movable part connected to a motor. Background Technology

[0002] Patent Document 1 discloses a drive control device that calculates the characteristics of an acceleration sensor mounted on a movable part connected to a motor.

[0003] Based on the aforementioned conventional drive control device, it is possible to determine abnormalities related to the operation and installation direction of the acceleration sensor.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2006-155180 Summary of the Invention

[0007] The problem the invention aims to solve

[0008] In the aforementioned conventional drive control device, abnormalities related to the operation and installation direction of the acceleration sensor are determined based on the acceleration detection value output from the acceleration sensor. Therefore, for example, in cases where the acceleration sensor detaches from the movable part, it is sometimes difficult to determine abnormalities related to the operation and installation direction of the acceleration sensor.

[0009] Therefore, this disclosure was made in view of the above-mentioned problems, and its object is to provide a characteristic calculation device that can determine abnormalities related to the operation or installation direction of the acceleration sensor even when the acceleration sensor is detached from the movable part.

[0010] Solution for solving the problem

[0011] One aspect of this disclosure relates to a characteristic calculation apparatus comprising: a sensor information acquisition unit that acquires position information and acceleration information, wherein the position information represents the position of a motor detected by a position detector, and the acceleration information represents the acceleration of the movable part detected by an acceleration sensor mounted on a movable part connected to the motor; and a sensor characteristic calculation unit that calculates at least one of balance information and detection sensitivity information based on the position information and the acceleration information, and outputs at least one of the calculated balance information and detection sensitivity information, wherein the balance information represents the degree of consistency between the detection axis direction of the acceleration sensor and the direction of the acceleration that the acceleration sensor should detect, and the detection sensitivity information represents the detection sensitivity of the acceleration sensor.

[0012] One aspect of this disclosure relates to a characteristic calculation method comprising the following steps: a sensor information acquisition step, acquiring position information and acceleration information, wherein the position information represents the position of a motor detected by a position detector, and the acceleration information represents the acceleration of the movable part detected by an acceleration sensor mounted on a movable part connected to the motor; and a sensor characteristic calculation step, calculating at least one of balance information and detection sensitivity information based on the position information and the acceleration information, and outputting at least one of the calculated balance information and detection sensitivity information, wherein the balance information represents the degree of consistency between the detection axis direction of the acceleration sensor and the direction of the acceleration that the acceleration sensor should detect, and the detection sensitivity information represents the detection sensitivity of the acceleration sensor.

[0013] One aspect of this disclosure relates to a program recording medium that records a program for causing a characteristic calculation device to perform characteristic calculation processing, the characteristic calculation processing including the following steps: a sensor information acquisition step, acquiring position information and acceleration information, wherein the position information represents the position of a motor detected by a position detector, and the acceleration information represents the acceleration of the movable part detected by an acceleration sensor mounted on a movable part connected to the motor; and a sensor characteristic calculation step, calculating at least one of balance information and detection sensitivity information based on the position information and the acceleration information, and outputting at least one of the calculated balance information and detection sensitivity information, wherein the balance information represents the degree of consistency between the detection axis direction of the acceleration sensor and the direction of the acceleration that the acceleration sensor should detect, and the detection sensitivity information represents the detection sensitivity of the acceleration sensor.

[0014] The effects of the invention

[0015] According to the characteristic calculation device or the like disclosed in one aspect, even in the case where the acceleration sensor detaches from the movable part, it is possible to determine the abnormality related to the operation or installation direction of the acceleration sensor. Attached Figure Description

[0016] Figure 1 This is a block diagram illustrating the structure of the motor control system according to the embodiment.

[0017] Figure 2 This is a schematic diagram illustrating an example of a sensor characteristic calculation unit calculating balance information or detection sensitivity information according to an embodiment.

[0018] Figure 3 This is a schematic diagram illustrating another example of a sensor characteristic calculation unit calculating balance information or detection sensitivity information according to an embodiment.

[0019] Figure 4 This is a schematic diagram illustrating an example of a sensor characteristic calculation unit calculating balance information or detection sensitivity information according to an embodiment.

[0020] Figure 5 This is a schematic diagram illustrating another example of a sensor characteristic calculation unit calculating balance information or detection sensitivity information according to an embodiment.

[0021] Figure 6 This is a schematic diagram illustrating a situation where the acceleration of the movable part causes ringing when the response time constant of the position control unit involved in the embodiment is relatively high.

[0022] Figure 7 This is a flowchart of the characteristic calculation process involved in the implementation method.

[0023] Figure 8 This is a block diagram showing the structure of the motor control system involved in Modification 1.

[0024] Figure 9 This is a schematic diagram showing the case where the position sensor involved in Modification Example 1 is installed in the movable part.

[0025] Figure 10 This is a block diagram showing the structure of the motor control system involved in Modification Example 2. Detailed Implementation

[0026] (One way in which this disclosure was obtained)

[0027] As mentioned above, in conventional drive control devices, for example, when the acceleration sensor detaches from the movable part, it is sometimes difficult to determine abnormalities related to the operation and installation direction of the acceleration sensor.

[0028] The inventors discovered the above-mentioned problem and, in order to solve it, conceived of the following characteristic calculation device, etc.

[0029] One aspect of this disclosure relates to a characteristic calculation apparatus comprising: a sensor information acquisition unit that acquires position information and acceleration information, wherein the position information represents the position of a motor detected by a position detector, and the acceleration information represents the acceleration of the movable part detected by an acceleration sensor mounted on a movable part connected to the motor; and a sensor characteristic calculation unit that calculates at least one of balance information and detection sensitivity information based on the position information and the acceleration information, and outputs at least one of the calculated balance information and detection sensitivity information, wherein the balance information represents the degree of consistency between the detection axis direction of the acceleration sensor and the direction of the acceleration that the acceleration sensor should detect, and the detection sensitivity information represents the detection sensitivity of the acceleration sensor.

[0030] According to the characteristic calculation device of the above structure, in addition to the acceleration of the movable part detected by the acceleration sensor, at least one of the balance information and the detection sensitivity information is calculated based on the position of the motor detected by the position detector.

[0031] Therefore, based on the characteristics of the above-described structure, even in the case where the acceleration sensor detaches from the movable part, it is possible to determine any abnormalities related to the operation or installation direction of the acceleration sensor.

[0032] Alternatively, the sensor characteristic calculation unit may calculate the at least one of the following if the acceleration of the motor calculated based on the position information does not change for a period of time or longer.

[0033] Therefore, it is possible to calculate at least one of the balance information and detection sensitivity information with higher accuracy.

[0034] Alternatively, it may also include: a command signal acquisition unit that acquires a command signal generated by a command generation unit for positioning the movable part at a target position; and a position control unit that generates a drive signal for driving the motor in a manner that moves the movable part to the target position based on the command signal and the position information, and outputs the generated drive signal to the motor, wherein the command generation unit generates the command signal in a manner that ensures that the acceleration of the motor indicated by the command signal does not change during a period longer than the predetermined period.

[0035] Therefore, it is possible to obtain a command signal that keeps the motor's acceleration unchanged during a specified period.

[0036] Alternatively, the instruction generation unit may also generate the instruction signal in such a way that the position of the motor indicated by the instruction signal does not change for a period of time beyond the specified period.

[0037] Therefore, it is possible to obtain a command signal that prevents the position of the motor from changing during a specified period.

[0038] Alternatively, it may also include: a command signal acquisition unit that acquires a command signal generated by a command generation unit for positioning the movable part at a target position; and a position control unit that generates a drive signal for driving the motor in a manner that moves the movable part to the target position based on the command signal and the position information, and outputs the generated drive signal to the motor, wherein the command generation unit generates the command signal in a manner that makes the acceleration of the motor indicated by the command signal a first value and does not change during a first period that is larger than the response time constant of the position control unit.

[0039] Therefore, it is possible to obtain a command signal that keeps the motor's acceleration unchanged during a period that is larger than the response time constant of the position control unit.

[0040] Alternatively, the instruction generation unit may generate the instruction signal such that, during the period when the sensor characteristic calculation unit calculates the at least one of the parameters, the acceleration of the motor indicated by the instruction signal is the first value and does not change during the first period, which is larger than the response time constant of the position control unit.

[0041] Therefore, it is possible to calculate at least one of the balance information and detection sensitivity information with higher accuracy.

[0042] Alternatively, it can be configured to also include a response time constant setting unit, which sets the response time constant in such a way that the first period is longer than the ringing period, and the ringing period is the duration of ringing generated by the acceleration of the movable part when the acceleration of the movable part converges to a second value corresponding to the first value.

[0043] This allows the first period to be longer than the ringing period.

[0044] Alternatively, the response time constant setting unit may set the response time constant such that the first period is longer than the ringing period by calculating the period of the at least one of the sensor characteristics in the sensor characteristic calculation unit.

[0045] Therefore, it is possible to calculate at least one of the balance information and detection sensitivity information with higher accuracy.

[0046] Alternatively, the sensor information acquisition unit may further acquire movable part position information, which represents the position of the movable part detected by a position sensor installed on the movable part, and the sensor characteristic calculation unit calculates the at least one based on the movable part position information and the acceleration information, rather than based on the position information and the acceleration information.

[0047] Therefore, it is possible to calculate at least one of the balance information and the detection sensitivity information using the position information of the movable part, rather than using the position information.

[0048] Alternatively, it can be configured to also include a calculation value determination unit, which outputs determination information indicating that at least one of the consistency and the detection sensitivity has deviated from the predetermined reference value when such deviation occurs.

[0049] Therefore, it is possible to notify users of the characteristic calculation device that there may be an anomaly related to the operation or installation direction of the acceleration sensor.

[0050] Alternatively, the sensor information acquisition unit may further acquire movable part position information, which represents the position of the movable part detected by the position sensor installed on the movable part. If at least either the consistency or the detection sensitivity deviates from a predetermined reference value, and the position of the movable part represented by the movable part position information meets a predetermined condition, the calculation value determination unit outputs the determination information.

[0051] This allows for more precise notification to users utilizing the characteristic computing device of potential anomalies related to the operation or installation orientation of the accelerometer.

[0052] Alternatively, it can be configured to also include a calculation value determination unit, which outputs determination information indicating that the change in the change in the at least one of the consistency and the detection sensitivity per unit time deviates from the predetermined reference value when such change deviates from the predetermined reference value.

[0053] Therefore, it is possible to notify users of the characteristic calculation device that there may be an anomaly related to the operation or installation direction of the acceleration sensor.

[0054] Alternatively, the acceleration sensor can be configured to be a triaxial acceleration sensor.

[0055] Therefore, it is possible to calculate at least one of the balance information and detection sensitivity information of the triaxial accelerometer.

[0056] One aspect of this disclosure relates to a characteristic calculation method comprising the following steps: a sensor information acquisition step, acquiring position information and acceleration information, wherein the position information represents the position of a motor detected by a position detector, and the acceleration information represents the acceleration of the movable part detected by an acceleration sensor mounted on a movable part connected to the motor; and a sensor characteristic calculation step, calculating at least one of balance information and detection sensitivity information based on the position information and the acceleration information, and outputting at least one of the calculated balance information and detection sensitivity information, wherein the balance information represents the degree of consistency between the detection axis direction of the acceleration sensor and the direction of the acceleration that the acceleration sensor should detect, and the detection sensitivity information represents the detection sensitivity of the acceleration sensor.

[0057] According to the above characteristic calculation method, in addition to the acceleration of the movable part detected by the acceleration sensor, the position of the motor detected by the position detector is also used to calculate at least one of the balance information and the detection sensitivity information.

[0058] Therefore, based on the above characteristic calculation method, even in the case where the accelerometer detaches from the movable part, it is possible to determine the abnormality related to the movement or installation direction of the accelerometer.

[0059] One aspect of this disclosure relates to a program recording medium that records a program for causing a characteristic calculation device to perform characteristic calculation processing, the characteristic calculation processing including the following steps: a sensor information acquisition step, acquiring position information and acceleration information, wherein the position information represents the position of a motor detected by a position detector, and the acceleration information represents the acceleration of the movable part detected by an acceleration sensor mounted on a movable part connected to the motor; and a sensor characteristic calculation step, calculating at least one of balance information and detection sensitivity information based on the position information and the acceleration information, and outputting at least one of the calculated balance information and detection sensitivity information, wherein the balance information represents the degree of consistency between the detection axis direction of the acceleration sensor and the direction of the acceleration that the acceleration sensor should detect, and the detection sensitivity information represents the detection sensitivity of the acceleration sensor.

[0060] According to the above procedure, in addition to the acceleration of the movable part detected by the accelerometer, at least one of the balance information and the detection sensitivity information is calculated based on the position of the motor detected by the position detector.

[0061] Therefore, according to the program recording medium of this disclosure which records the above-described program, even in the case where the accelerometer detaches from the movable part, it is possible to determine the abnormality related to the operation or installation direction of the accelerometer.

[0062] The following description, with reference to the accompanying drawings, illustrates a specific example of the characteristic calculation device according to one aspect of this disclosure. The embodiments shown herein represent specific 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 examples and are not intended to limit this disclosure. Furthermore, the figures are schematic diagrams and are not necessarily strictly illustrative. In the figures, substantially identical structures are labeled with the same reference numerals, and repeated descriptions are omitted or simplified.

[0063] (Implementation Method)

[0064] The motor control system according to the embodiment will now be described. This motor control system is a system that controls a motor to move a movable part connected to the motor to a target position. This motor control system may also be, for example, a production apparatus for mounting components onto a substrate.

[0065] <Structure>

[0066] Figure 1 This is a block diagram showing the structure of the motor control system 1 according to the embodiment.

[0067] like Figure 1 As shown, the motor control system 1 includes a characteristic calculation device 10, a motor 70, a movable part 80, a command generation unit 90, a position detector 71, and an acceleration sensor 81.

[0068] The motor 70 is driven according to the drive signal output from the characteristic calculation device 10. Here, the motor 70 is described as a rotary motor. However, the motor 70 is not necessarily limited to a rotary motor; for example, it may also be a linear motor.

[0069] The drive signal is, for example, the current used to rotate the motor 70.

[0070] The position detector 71 detects the position of the motor 70 and outputs position information indicating the detected position of the motor 70 to the characteristic calculation device 10.

[0071] The position detector 71 can be installed on the motor 70 or not.

[0072] The position detector 71 can also be an encoder, for example. In this case, the position information output by the position detector 71 is an encoder signal.

[0073] Here, the position detector 71 is described as an encoder installed on the motor 70.

[0074] The movable part 80 is connected to the motor 70. For example, in the case where the motor control system 1 is a production apparatus for mounting components onto a substrate, the movable part 80 is a header for moving the components to the mounting position.

[0075] An acceleration sensor 81 is mounted on the movable part 80 to detect the acceleration of the movable part 80 and outputs acceleration information representing the detected acceleration of the movable part 80 to the characteristic calculation device 10.

[0076] The command generation unit 90 generates a command signal for positioning the movable part 80 at a target position and outputs the generated command signal to the characteristic calculation device 10. The command signal may be, for example, a position command signal representing a position command for positioning the movable part 80 at the target position, a speed command signal representing a speed command for positioning the movable part 80 at the target position, an acceleration command signal representing an acceleration command for positioning the movable part 80 at the target position, or a torque command signal representing a torque command for positioning the movable part 80 at the target position.

[0077] The characteristic calculation device 10 is input with command signals, position information and acceleration information, and outputs at least one of (1) balance information and detection sensitivity information, (2) judgment information and (3) drive signal, wherein the balance information indicates the degree of consistency between the detection axis direction of the acceleration sensor 81 and the direction of the acceleration that the acceleration sensor 81 should detect (hereinafter also referred to as "balance"), the detection sensitivity information indicates the detection sensitivity of the acceleration sensor 81, and the judgment information indicates that at least one of the balance of the acceleration sensor 81 and the detection sensitivity of the acceleration sensor 81 deviates from a specified reference value.

[0078] The feature calculation device 10 can also be implemented, for example, by having a processor execute a program stored in memory in a computer device equipped with a processor, memory, and input / output interfaces. Alternatively, the feature calculation device 10 can also be implemented, for example, by dedicated hardware circuitry. Furthermore, the feature calculation device 10 can also be implemented by a combination of a computer device with a processor executing a program stored in memory and dedicated hardware circuitry.

[0079] The characteristic calculation device 10 includes a sensor information acquisition unit 20, a sensor characteristic calculation unit 30, a command signal acquisition unit 40, a position control unit 50, a calculated value determination unit 60, and a response time constant setting unit 65.

[0080] The sensor information acquisition unit 20 acquires position information output from the position detector 71 and acceleration information output from the acceleration sensor 81.

[0081] The instruction signal acquisition unit 40 acquires the instruction signal output from the instruction generation unit 90.

[0082] The position control unit 50 generates a drive signal for moving the movable part 80 to a target position based on the command signal acquired by the command signal acquisition unit 40 and the position information acquired by the sensor information acquisition unit 20, and outputs the generated drive signal to the motor 70.

[0083] The position control unit 50 may generate a drive signal by performing feedback control that feeds back the position information acquired by the sensor information acquisition unit 20 in response to the command signal acquired by the command signal acquisition unit 40.

[0084] The sensor characteristic calculation unit 30 calculates at least one of the balance information and the detection sensitivity information based on the position information and acceleration information acquired by the sensor information acquisition unit 20, and outputs at least one of the calculated balance information and detection sensitivity information.

[0085] Figure 2 This is a schematic diagram illustrating an example of a sensor characteristic calculation unit 30 calculating balance information or detection sensitivity information based on position information and acceleration information.

[0086] This example illustrates a case where the accelerometer 81 is a triaxial accelerometer that detects acceleration along three mutually orthogonal axes: the X-axis, Y-axis, and Z-axis.

[0087] like Figure 2 As shown, during periods when the accelerometer 81 is not accelerating, i.e., during periods when the accelerometer 81 is in uniform linear motion or stationary, the accelerometer 81 detects gravitational acceleration g. Therefore, the accelerometer 81 outputs acceleration information representing the gravitational acceleration g in the X-axis component gx, Y-axis component gy, and Z-axis component gz.

[0088] When the sensor characteristic calculation unit 30 acquires the acceleration information, it uses equation (1) to calculate the gravitational acceleration g detected by the acceleration sensor 81.

[0089] [Number 1]

[0090]

[0091] Then, the sensor characteristic calculation unit 30 calculates the detection sensitivity of the acceleration sensor 81 based on the ratio of the calculated gravitational acceleration g to the actual gravitational acceleration.

[0092] In addition, the sensor characteristic calculation unit 30 uses equations (2), (3), and (4) to calculate the balance α, β, and γ of the X-axis, Y-axis, and Z-axis of the accelerometer sensor 81 based on the acquired acceleration information.

[0093] [Number 2]

[0094]

[0095] [Number 3]

[0096]

[0097] [Number 4]

[0098]

[0099] In this example, the sensor characteristic calculation unit 30 performs the calculation of the balance information or detection sensitivity information when the acceleration of the motor 70 calculated based on the position information does not change for a period of time or longer. Particularly preferred is that the sensor characteristic calculation unit 30 performs the calculation of the balance information or detection sensitivity information when the position of the motor 70 calculated based on the position information does not change for a period of time or longer.

[0100] To achieve this, it is preferable that the command generation unit 90 generates a command signal in such a way that the acceleration of the motor 70 does not change for a period of time or longer. It is particularly preferable that the command generation unit 90 generates a command signal in such a way that the position of the motor 70 does not change for a period of time or longer.

[0101] Figure 3 This is a schematic diagram illustrating another example of how the sensor characteristic calculation unit 30 calculates balance information or detection sensitivity information based on position information and acceleration information.

[0102] This example illustrates a case where the accelerometer 81 is mounted on the movable part 80 as a single-axis accelerometer with its detection axis oriented toward the acceleration direction of the movable part 80.

[0103] like Figure 3 As shown, when the command generation unit 90 outputs a command signal indicating that the movable part 80 should accelerate at a first value for a fixed period of time, the motor 70 and the movable part 80 accelerate in a manner that follows the command signal with a slight delay. Furthermore, the acceleration of the motor 70 converges towards the first value indicated by the command signal, and the acceleration of the movable part 80 converges towards a second value corresponding to the first acceleration.

[0104] Figure 3An example is the case where the balance and sensitivity of the accelerometer 81 are ideal (the detection axis of the accelerometer 81 is consistent with the acceleration direction of the movable part 80, and the sensitivity is consistent with the specified value) and the first value at which the acceleration of the motor 70 converges is equal to the second value at which the acceleration of the movable part 80 converges.

[0105] The sensor characteristic calculation unit 30 calculates the time shift of the acceleration of the motor 70 by performing a second-order derivative of the position information acquired by the sensor information acquisition unit 20. In addition, it calculates the time shift of the acceleration of the movable part 80 based on the acceleration information acquired by the sensor information acquisition unit 20.

[0106] Then, the sensor characteristic calculation unit 30 compares the calculated acceleration of the motor 70 within a fixed acceleration interval over time (i.e., the first value to which the acceleration of the motor 70 converges) with the calculated acceleration of the movable part 80 within a fixed acceleration interval over time (i.e., the second value to which the acceleration of the movable part 80 converges). If the balance and sensitivity of the acceleration sensor 81 deviate from the ideal situation, a difference is generated in the comparison result. The sensor characteristic calculation unit 30 calculates the balance or detection sensitivity of the acceleration sensor 81 based on the comparison result.

[0107] In this case, the sensor characteristic calculation unit 30 performs the above-mentioned balance information or detection sensitivity information if the acceleration of the motor 70 calculated based on the position information does not change for a period of time or longer.

[0108] To achieve this, it is preferable that the command generation unit 90 generates a command signal in such a way that the acceleration of the motor 70 does not change for a period longer than a predetermined period.

[0109] In addition, in order to calculate the aforementioned balance information or detection sensitivity information, the sensor characteristic calculation unit 30 needs to converge the acceleration of the motor 70 to a first value and the acceleration of the movable part 80 to a second value.

[0110] To achieve this, the command generation unit 90 generates a command signal such that the acceleration of the motor 70 indicated by the command signal is a first value and remains unchanged for a period longer than the response time constant of the position control unit 50. Particularly preferred is that the command generation unit 90 generates the command signal while the sensor characteristic calculation unit 30 is calculating the aforementioned balance information or detection sensitivity information. Here, the response time constant refers to the period from when the command signal is input to the position control unit 50 until the position control unit 50 drives the motor 70 to the acceleration of the motor 70 determined according to the command signal.

[0111] Figure 4 This is a schematic diagram illustrating an example of the following situation: When the command generation unit 90 generates a command signal in such a way that the acceleration of the motor 70 indicated by the command signal is a first value and changes only during a period smaller than the response time constant of the position control unit 50, the sensor characteristic calculation unit 30 calculates balance information or detection sensitivity information based on position information and acceleration information.

[0112] like Figure 4 As shown, when the command generation unit 90 outputs a command signal indicating that the movable part 80 should accelerate at a first value during a fixed period smaller than the response time constant of the position control unit 50, the motor 70 and the movable part 80 accelerate in a manner that follows the command signal with a slight delay. However, the acceleration of the motor 70 does not sufficiently converge to the first value indicated by the command signal, and the acceleration of the movable part 80 also does not sufficiently converge to the second value corresponding to the first acceleration.

[0113] Therefore, the sensor characteristic calculation unit 30 cannot calculate the balance or detection sensitivity of the accelerometer 81 with high accuracy.

[0114] Figure 5 This is a schematic diagram illustrating another example of how the sensor characteristic calculation unit 30 calculates balance information or detection sensitivity information based on position information and acceleration information.

[0115] This example illustrates a case where the accelerometer 81 is mounted on the movable part 80 as a single-axis accelerometer with its detection axis oriented toward the acceleration direction of the movable part 80.

[0116] like Figure 5 As shown, when the command generation unit 90 outputs a command signal that means the change in acceleration of the motor 70 and the change in acceleration of the movable part 80 are sinusoidal waves, the change in acceleration of the motor 70 and the change in acceleration of the movable part 80 are sinusoidal waves.

[0117] Figure 5 An example is the case where the accelerometer 81 has ideal balance and sensitivity (the detection axis of the accelerometer 81 is consistent with the acceleration direction of the movable part 80, and the sensitivity is consistent with the specification value) and the amplitude of the acceleration of the motor 70 over time is equal to the amplitude of the acceleration of the movable part 80 over time.

[0118] At this time, the sensor characteristic calculation unit 30 calculates the time shift of the acceleration of the motor 70 by performing a second-order derivative of the position information acquired by the sensor information acquisition unit 20. In addition, it calculates the time shift of the acceleration of the movable part 80 based on the acceleration information acquired by the sensor information acquisition unit 20.

[0119] Then, the sensor characteristic calculation unit 30 compares the calculated amplitude of the acceleration of the motor 70 over time with the calculated amplitude of the acceleration of the movable part 80 over time. If the balance and sensitivity of the acceleration sensor 81 deviate from the ideal situation, a difference is generated in the comparison result. The sensor characteristic calculation unit 30 calculates the balance or detection sensitivity of the acceleration sensor 81 based on the comparison result.

[0120] Return to Figure 1 Let's continue with the explanation of the motor control system 1.

[0121] The calculation value determination unit 60 determines whether at least one of the balance degree represented by the balance degree information and the detection sensitivity represented by the detection sensitivity information calculated by the sensor characteristic calculation unit 30 deviates from a predetermined reference value. If it is determined that the balance degree represented by the balance degree information and the detection sensitivity represented by the detection sensitivity information deviate from the predetermined reference value, the calculation value determination unit 60 outputs determination information indicating that at least one of the balance degree represented by the balance degree information and the detection sensitivity represented by the detection sensitivity information deviates from the predetermined reference value.

[0122] When the command generation unit 90 generates a command signal such that the acceleration of the motor 70 indicated by the command signal is a first value and does not change during a first period longer than the response time constant of the position control unit 50, the response time constant setting unit 65 sets the response time constant of the position control unit 50 such that the first period is longer than the ringing period, wherein the ringing period is the duration of ringing generated by the acceleration of the movable part 80 when the acceleration of the movable part 80 converges to a second value corresponding to the first value. Particularly preferably, the response time constant setting unit 65 sets the response time constant during the period when the sensor characteristic calculation unit 30 calculates balance information or detection sensitivity information.

[0123] The response time constant setting unit 65 may, for example, be configured to set the response time constant of the position control unit 50 by updating the gain parameter in the position control unit 50 used to determine the gain of the drive signal relative to the command signal.

[0124] Figure 6 This is a schematic diagram illustrating a situation where the acceleration of the movable part 80 causes ringing when the response time constant of the position control unit 50 is relatively high. In contrast, Figure 3 This is a schematic diagram showing the situation where the acceleration of the movable part 80 does not produce ringing when the response time constant of the position control unit 50 is relatively low.

[0125] like Figure 6As shown, when the response time constant of the position control unit 50 is relatively high, the acceleration of the movable part 80 increases sharply. Therefore, the acceleration of the movable part 80 produces ringing. When the sensor characteristic calculation unit 30 calculates the balance or detection sensitivity of the acceleration sensor 81 under such ringing conditions, the calculation accuracy of the balance or detection sensitivity of the acceleration sensor 81 may decrease.

[0126] In contrast, such as Figure 3 As shown, when the response time constant of the position control unit 50 is relatively low, the acceleration of the movable part 80 increases slowly. Therefore, the acceleration of the movable part 80 does not produce ringing. In this state where ringing does not occur, the sensor characteristic calculation unit 30 calculates the balance or detection sensitivity of the acceleration sensor 81, thereby suppressing the decrease in the calculation accuracy of the balance or detection sensitivity of the acceleration sensor 81.

[0127] <Action>

[0128] The operation of the characteristic calculation device 10 of the above structure will now be explained.

[0129] The characteristic calculation device 10 performs characteristic calculation processing to calculate at least one of the balance information and the detection sensitivity information based on the position information and acceleration information, and outputs the calculated balance information and the detection sensitivity information.

[0130] For example, characteristic calculation processing can begin by outputting position information from position detector 71 and acceleration information from acceleration sensor 81.

[0131] Figure 7 This is a flowchart of the characteristic calculation process performed by the characteristic calculation device 10.

[0132] like Figure 7 As shown, when the characteristic calculation process begins, the sensor information acquisition unit 20 acquires the position information output from the position detector 71 and the acceleration information output from the acceleration sensor 81 (step S10).

[0133] When position information and acceleration information are acquired, the sensor characteristic calculation unit 30 calculates at least one of balance information and detection sensitivity information based on the position information and acceleration information acquired by the sensor information acquisition unit 20, and outputs at least one of the calculated balance information and detection sensitivity information (step S20).

[0134] When at least one of the balance information and the detection sensitivity information is calculated, the calculation value determination unit 60 determines whether at least one of the balance information represented by the balance information and the detection sensitivity information represented by the detection sensitivity information calculated by the sensor characteristic calculation unit 30 deviates from the specified reference value (step S30).

[0135] In the process of step S30, if at least one of the above-mentioned balance and detection sensitivity deviates from the prescribed reference value (step S30: "Yes"), the calculation value determination unit 60 outputs determination information indicating that at least one of the above-mentioned balance and detection sensitivity deviates from the prescribed reference value (step S40).

[0136] If the processing in step S40 ends, and if at least one of the above-mentioned balance and detection sensitivity does not deviate from the specified reference value in the processing in step S30 (step S30: "No"), the characteristic calculation device 10 ends the characteristic calculation process.

[0137] <Inspection>

[0138] As described above, the characteristic calculation device 10 of the above structure calculates at least one of balance information and detection sensitivity information based not only on the acceleration of the movable part 80 detected by the acceleration sensor 81, but also on the position of the motor 70 detected by the position detector 71.

[0139] Therefore, based on the characteristics of the above-described structure, the calculation device 10 can determine any abnormalities related to the operation or installation direction of the acceleration sensor 81, even if the acceleration sensor 81 is detached from the movable part 80.

[0140] Furthermore, as described above, if at least one of the balance degree represented by the balance degree information and the detection sensitivity represented by the detection sensitivity information deviates from a predetermined reference value, the characteristic calculation device 10 of the above structure outputs judgment information indicating that at least one of the balance degree represented by the balance degree information and the detection sensitivity represented by the detection sensitivity information deviates from the predetermined reference value.

[0141] Therefore, the characteristic calculation device 10 with the above structure can notify the user using the characteristic calculation device 10 that an anomaly may have occurred related to the operation or installation direction of the acceleration sensor 81.

[0142] (Variation Example 1)

[0143] The following describes a motor control system according to a modified example 1, which is constructed by changing a part of the motor control system 1 according to the embodiment.

[0144] The motor control system 1 described in the embodiment is an example of a structure in which a position detector 71 is mounted on a motor 70 and an acceleration sensor 81 is mounted on a movable part 80. In contrast, the motor control system described in Modified Example 1 is an example of a structure in which a position detection sensor for further detecting the position of the movable part 80 is mounted on the movable part 80.

[0145] Hereinafter, regarding the motor control system involved in Modification 1, the constituent elements that are the same as those of the motor control system 1 involved in the embodiment will be described in detail and marked with the same reference numerals, and their detailed descriptions will be omitted. The description will focus on the differences from the motor control system 1.

[0146] Figure 8 This is a block diagram showing the structure of the motor control system 1A involved in Modification 1.

[0147] like Figure 8 As shown, the motor control system 1A is configured by adding a position sensor 82 and changing the characteristic calculation device 10 to a characteristic calculation device 10A, compared to the motor control system 1 according to Embodiment 1. Furthermore, the characteristic calculation device 10A is configured by changing the sensor information acquisition unit 20 to a sensor information acquisition unit 20A and the calculated value determination unit 60 to a calculated value determination unit 60A, compared to the characteristic calculation device 10.

[0148] A position sensor 82 is mounted on the movable part 80 to detect the position of the movable part 80 and outputs the movable part position information, which indicates the detected position of the movable part 80, to the characteristic calculation device 10A.

[0149] Figure 9 This is a schematic diagram showing the position sensor 82 mounted on a movable part 80 connected to a motor 70 via a screw 72.

[0150] like Figure 9 As shown, the position sensor 82 may, for example, be configured to detect the position of the movable part 80 by reading the value of the scale 84 engraved on a scale 83 indicating the position of the movable part 80. In this case, the position sensor 82 may, for example, be configured to have a camera device for capturing the scale 84 on the scale 83, and detect the position of the movable part 80 by performing image processing on the image captured by the camera device.

[0151] Return to Figure 8 Let's continue with the explanation of the motor control system 1A.

[0152] The sensor information acquisition unit 20A acquires position information output from position detector 71, acceleration information output from acceleration sensor 81, and position information of movable part output from position sensor 82.

[0153] The calculation value determination unit 60A determines whether at least one of the balance degree represented by the balance degree information and the detection sensitivity represented by the detection sensitivity information calculated by the sensor characteristic calculation unit 30 deviates from a predetermined reference value. If it is determined that the balance degree information deviates from the predetermined reference value, and the position of the movable part 80 represented by the movable part position information acquired by the sensor information acquisition unit 20A meets the predetermined conditions, the unit outputs determination information indicating that at least one of the balance degree information represented by the balance degree information and the detection sensitivity represented by the detection sensitivity information deviates from the predetermined reference value.

[0154] <Inspection>

[0155] As described above, when at least one of the balance degree represented by the balance degree information and the detection sensitivity represented by the detection sensitivity information deviates from a predetermined reference value, and when the position of the movable part 80 represented by the movable part position information meets a predetermined condition, the characteristic calculation device 10A of the above structure outputs judgment information indicating that at least one of the balance degree represented by the balance degree information and the detection sensitivity represented by the detection sensitivity information deviates from a predetermined reference value.

[0156] Therefore, the characteristic calculation device 10A with the above structure can notify the user using the characteristic calculation device 10A with higher accuracy that there may be an abnormality related to the operation or installation direction of the acceleration sensor 81.

[0157] Furthermore, while the sensor characteristic calculation unit 30 is described as calculating at least one of balance information and detection sensitivity information based on the position information and acceleration information acquired by the sensor information acquisition unit 20, in Modification 1, the sensor characteristic calculation unit 30 may also be configured to calculate at least one of balance information and detection sensitivity information based on the movable part position information and acceleration information acquired by the sensor information acquisition unit 20, rather than the position information and acceleration information acquired by the sensor information acquisition unit 20. Additionally, the sensor characteristic calculation unit 30 may also be configured to calculate at least one of balance information and detection sensitivity information based on the position information, movable part position information, and acceleration information acquired by the sensor information acquisition unit 20. Furthermore, in Modification 1, the constituent elements of the characteristic calculation device 10A may be configured to perform various processing using the movable part position information, rather than the position of the motor 70 represented by the position information, for various processing purposes.

[0158] (Variation Example 2)

[0159] The following describes a modified motor control system, which is a modified version 2 of the motor control system 1 according to the embodiment, by changing a part of it.

[0160] The motor control system 1 according to the embodiment is an example of a structure in which, when at least one of the balance degree represented by the balance degree information and the detection sensitivity represented by the detection sensitivity information, calculated by the sensor characteristic calculation unit 30, deviates from a predetermined reference value, the characteristic calculation device 10 outputs determination information indicating that at least one of the balance degree represented by the balance degree information and the detection sensitivity represented by the detection sensitivity information deviates from the predetermined reference value. In contrast, the motor control system according to Modification 2 is an example of a structure in which, when the change per unit time of at least one of the balance degree represented by the balance degree information and the detection sensitivity represented by the detection sensitivity information, calculated by the sensor characteristic calculation unit 30, deviates from a predetermined reference value, the characteristic calculation device according to Modification 2 outputs determination information indicating that the change per unit time of at least one of the balance degree represented by the balance degree information and the detection sensitivity represented by the detection sensitivity information deviates from the predetermined reference value.

[0161] Hereinafter, regarding the motor control system involved in Modification Example 2, the constituent elements that are the same as those of the motor control system 1 involved in the embodiment will be described in detail and marked with the same reference numerals, and their detailed descriptions will be omitted. The description will focus on the differences from the motor control system 1.

[0162] Figure 10 This is a block diagram showing the structure of the motor control system 1B involved in Modification Example 2.

[0163] like Figure 10 As shown, the motor control system 1B is configured by replacing the characteristic calculation device 10 with a characteristic calculation device 10B, relative to the motor control system 1 according to Embodiment 1. Furthermore, the characteristic calculation device 10B is configured by replacing the calculated value determination unit 60 with a calculated value determination unit 60B, relative to the characteristic calculation device 10.

[0164] The calculation value determination unit 60B determines whether the change per unit time of at least one of the balance degree represented by the balance degree information and the detection sensitivity represented by the detection sensitivity information calculated by the sensor characteristic calculation unit 30 deviates from a predetermined reference value. If it is determined that the change per unit time of at least one of the balance degree represented by the balance degree information and the detection sensitivity represented by the detection sensitivity information deviates from the predetermined reference value, the calculation value determination unit 60B outputs determination information indicating that the change per unit time of at least one of the balance degree represented by the balance degree information and the detection sensitivity represented by the detection sensitivity information deviates from the predetermined reference value.

[0165] <Inspection>

[0166] As described above, when the change in at least one of the balance degree represented by the balance degree information and the detection sensitivity represented by the detection sensitivity information deviates from a predetermined reference value per unit time, the characteristic calculation device 10B of the above structure outputs judgment information indicating that the change in at least one of the balance degree represented by the balance degree information and the detection sensitivity represented by the detection sensitivity information deviates from the predetermined reference value per unit time.

[0167] Therefore, the characteristic calculation device 10B with the above structure can notify the user using the characteristic calculation device 10B that there may be an abnormality related to the operation or installation direction of the acceleration sensor 81.

[0168] (Replenish)

[0169] As described above, the embodiments and variations 1-2 have been presented as examples of the technology disclosed in this application. However, this disclosure is not limited to these embodiments and variations 1-2. It is also possible that, without departing from the spirit of this disclosure, various modifications to the embodiments or variations that can be conceived by those skilled in the art, and combinations of constituent elements from different embodiments or variations, are also included within the scope of one or more embodiments of this disclosure.

[0170] One aspect of this disclosure is not limited to the characteristic calculation device 10, but also includes a characteristic calculation method that sets the characteristic structural parts included in the characteristic calculation device 10 as steps. Another aspect of this disclosure is a computer program for causing a computer to execute the characteristic steps included in the characteristic calculation method. Furthermore, another aspect of this disclosure is a computer-readable non-transitory recording medium on which such a computer program is recorded.

[0171] Industrial availability

[0172] This disclosure can be widely used in systems that calculate the characteristics of an acceleration sensor mounted on a movable part connected to a motor, etc.

[0173] Explanation of reference numerals in the attached figures

[0174] 1, 1A, 1B: Motor control system; 10, 10A, 10B: Characteristic calculation device; 20, 20A: Sensor information acquisition unit; 30: Sensor characteristic calculation unit; 40: Command signal acquisition unit; 50: Position control unit; 60, 60A, 60B: Calculated value determination unit; 65: Response time constant setting unit; 70: Motor; 71: Position detector; 72: Screw; 80: Movable part; 81: Accelerometer; 82: Position sensor; 83: Scale; 84: Gradient; 90: Command generation unit.

Claims

1. A characteristic calculation device, comprising: The sensor information acquisition unit acquires position information and acceleration information, wherein... The position information indicates the position of the motor detected by the position detector, and the acceleration information indicates the acceleration of the movable part detected by the acceleration sensor installed on the movable part connected to the motor. as well as The sensor characteristic calculation unit calculates at least one of balance information and detection sensitivity information based on the position information and the acceleration information, provided that the acceleration of the motor calculated based on the position information does not change for a period of time or longer. The unit then outputs at least one of the calculated balance information and detection sensitivity information. The balance information represents the degree of consistency between the detection axis direction of the acceleration sensor and the direction of the acceleration that the acceleration sensor should detect, and the detection sensitivity information represents the detection sensitivity of the acceleration sensor.

2. The characteristic calculation device according to claim 1, further comprising: A command signal acquisition unit acquires a command signal generated by a command generation unit for positioning the movable part at a target position; and The position control unit generates a drive signal based on the command signal and the position information to drive the motor in a manner that moves the movable part to the target position, and outputs the generated drive signal to the motor. The command generation unit generates the command signal in such a way that the acceleration of the motor indicated by the command signal does not change during a period longer than the specified period.

3. The characteristic calculation device according to claim 2, wherein, The command generation unit also generates the command signal in such a way that the position of the motor indicated by the command signal does not change for a period of time longer than the specified period.

4. The characteristic calculation device according to claim 1, further comprising: A command signal acquisition unit acquires a command signal generated by a command generation unit for positioning the movable part at a target position; and The position control unit generates a drive signal based on the command signal and the position information to drive the motor in a manner that moves the movable part to the target position, and outputs the generated drive signal to the motor. The command generation unit generates the command signal in such a way that the acceleration of the motor indicated by the command signal is a first value and does not change during a first period that is larger than the response time constant of the position control unit.

5. The characteristic calculation device according to claim 4, wherein, The command generation unit generates the command signal in such a way that the acceleration of the motor indicated by the command signal is the first value and does not change during the first period, which is larger than the response time constant of the position control unit, while the sensor characteristic calculation unit calculates the at least one of the parameters.

6. The characteristic calculation device according to claim 4 or 5, wherein, It also includes a response time constant setting unit, which sets the response time constant. The response time constant setting unit sets the response time constant in such a way that the first period is longer than the ringing period, wherein the ringing period is the duration of ringing generated by the acceleration of the movable part when the acceleration of the movable part converges to a second value corresponding to the first value.

7. The characteristic calculation device according to claim 6, wherein, The response time constant setting unit sets the response time constant in such a way that the first period is longer than the ringing period, based on the period calculated by the sensor characteristic calculation unit for at least one of the at least one sensor characteristic calculation unit.

8. The characteristic calculation apparatus according to any one of claims 1 to 5, wherein, The sensor information acquisition unit further acquires movable part position information, which represents the position of the movable part detected by a position sensor installed on the movable part. The sensor characteristic calculation unit calculates at least one of the information based on the position information and acceleration information, rather than the position information and acceleration information.

9. The characteristic calculation apparatus according to any one of claims 1 to 5, wherein, It also includes a calculation value determination unit, which outputs determination information indicating that at least one of the consistency and the detection sensitivity has deviated from the predetermined reference value when the calculation value determination unit outputs determination information indicating that the at least one has deviated from the predetermined reference value.

10. The characteristic calculation device according to claim 9, wherein, The sensor information acquisition unit further acquires movable part position information, which represents the position of the movable part detected by a position sensor installed on the movable part. If at least one of the consistency and the detection sensitivity deviates from the specified reference value, and the position of the movable part represented by the movable part position information meets the specified conditions, the calculation value determination unit outputs the determination information.

11. The characteristic calculation apparatus according to any one of claims 1 to 5, wherein, It also includes a calculation value determination unit, which outputs determination information indicating that the change in the change in the at least one of the consistency and the detection sensitivity per unit time deviates from the predetermined reference value when the change in the at least one of the consistency and the detection sensitivity deviates from the predetermined reference value.

12. The characteristic calculation apparatus according to any one of claims 1 to 5, wherein, The accelerometer is a triaxial accelerometer.

13. A characteristic calculation method, comprising the following steps: The sensor information acquisition step acquires position information and acceleration information, wherein the position information represents the position of the motor detected by the position detector, and the acceleration information represents the acceleration of the movable part detected by the acceleration sensor installed on the movable part connected to the motor; and The sensor characteristic calculation step involves calculating at least one of balance information and detection sensitivity information based on the position information and the acceleration information, provided that the acceleration of the motor calculated based on the position information does not change for a period of time or longer. The calculated balance information and detection sensitivity information are then output. The balance information represents the degree of consistency between the detection axis direction of the acceleration sensor and the direction of the acceleration that the acceleration sensor should detect, and the detection sensitivity information represents the detection sensitivity of the acceleration sensor.

14. A program recording medium having a program stored thereon for causing a characteristic calculation device to perform characteristic calculation processing. The characteristic calculation process includes the following steps: The sensor information acquisition step acquires position information and acceleration information, wherein the position information represents the position of the motor detected by the position detector, and the acceleration information represents the acceleration of the movable part detected by the acceleration sensor installed on the movable part connected to the motor; and The sensor characteristic calculation step involves calculating at least one of balance information and detection sensitivity information based on the position information and the acceleration information, provided that the acceleration of the motor calculated based on the position information does not change for a period of time or longer. The calculated balance information and detection sensitivity information are then output. The balance information represents the degree of consistency between the detection axis direction of the acceleration sensor and the direction of the acceleration that the acceleration sensor should detect, and the detection sensitivity information represents the detection sensitivity of the acceleration sensor.

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