JP7603850B2 - Inspection device, inspection method, and inspection program - Google Patents

Description

The present disclosure relates to an inspection device, an inspection method, and an inspection program for inspecting the condition of an object.

Patent Document 1 discloses a work judgment system having a motion matching unit that recognizes physical movements by matching a combination of information output from multiple sensors provided in a glove-type wearable sensor, a signal judgment unit that judges whether the work content of the worker has been performed correctly based on the physical movements recognized by the motion matching unit, and a notification unit that notifies the result of the judgment by the signal judgment unit.

JP 2020-064429 A

However, the above document does not disclose a method for automatically determining whether an operator is shaking an object. Therefore, it is not possible to determine whether an inspection is performed while shaking an object.

The object of the present disclosure is to provide an inspection device, an inspection method, and an inspection program that make it possible to determine whether an object is being grasped and shaken.

The inspection device disclosed herein is an inspection device for inspecting a state of an object, the inspection device including a first pressure sensor having a first pressure sensitive surface and outputting a first electrical signal corresponding to a first pressure applied from the object to the first pressure sensitive surface, and a second pressure sensor having a second pressure sensitive surface and outputting a second electrical signal corresponding to a second pressure applied from the object to the second pressure sensitive surface, and based on the first electrical signal and the second electrical signal, the inspection device determines whether the state of the object is such that the object is pinched and grasped between the first pressure sensitive surface and the second pressure sensitive surface. and a vibration state determination unit which determines whether the object is in a gripping vibration state in which the object is held between the first pressure sensitive surface and the second pressure sensitive surface and is being shaken, or in a gripping stationary state in which the object is sandwiched and held between the first pressure sensitive surface and the second pressure sensitive surface and is not being shaken, and which determines that the object is in the gripping vibration state if a cross-correlation value between the first electrical signal and the second electrical signal is equal to or greater than a predetermined first threshold value .

The inspection method of the present disclosure is an inspection method for inspecting a state of an object, which is performed by an inspection device including a first pressure sensor having a first pressure-sensitive surface and outputting a first electrical signal corresponding to a first pressure applied from an object to the first pressure-sensitive surface, and a second pressure sensor having a second pressure-sensitive surface and outputting a second electrical signal corresponding to a second pressure applied from the object to the second pressure-sensitive surface, and the inspection method includes determining whether the state of the object is a pressure difference between the first pressure-sensitive surface and the second pressure-sensitive surface based on the first electrical signal and the second electrical signal. The method includes a step of determining whether the object is in a gripping vibration state in which the object is clamped and grasped and the first pressure sensor and the second pressure sensor are vibrating, or in a gripping stationary state in which the object is clamped and grasped between the first pressure sensitive surface and the second pressure sensitive surface and the first pressure sensor and the second pressure sensor are not vibrating, and determining that the object is in the gripping vibration state if a cross-correlation value between the first electrical signal and the second electrical signal is equal to or greater than a predetermined first threshold value .

By using the inspection device, inspection method, or inspection program disclosed herein, it is possible to determine whether an object is being grasped and shaken.

1 is a functional block diagram illustrating a configuration of an inspection device according to a first embodiment. 1 is a plan view illustrating an example in which a first pressure sensor and a second pressure sensor of an inspection device according to a first embodiment are provided in a glove that is a glove-shaped holding member. 1 is a side view illustrating an inspection device according to a first embodiment of the present invention; 2 is a diagram illustrating an example of a hardware configuration of an inspection device according to a first embodiment; FIG. 2 is a side view showing a non-gripped state in which an object is not being gripped. FIG. 2 is a side view showing a gripping stationary state in which an object is being gripped. FIG. 13 is a side view showing a gripping and vibration state in which an object is gripped and shaken. 4 is a waveform diagram showing an example of detection signals output from a first pressure sensor and a second pressure sensor of the inspection device according to the first embodiment. 4 is a flowchart showing an operation of the inspection device according to the first embodiment. FIG. 11 is a functional block diagram illustrating a configuration of an inspection device according to a second embodiment. 13 is a plan view that illustrates an example in which a first pressure sensor, a second pressure sensor, and an acceleration sensor of an inspection device according to a second embodiment are provided on a glove. FIG. FIG. 11 is a side view illustrating an inspection device according to a second embodiment. FIG. 11 is a diagram illustrating an example of a hardware configuration of an inspection device according to a second embodiment. 13 is a waveform diagram showing an example of detection signals output from the first pressure sensor, the second pressure sensor, and the acceleration sensor of the inspection device of embodiment 2 (when there is "rattling"). 13 is a waveform diagram showing an example of detection signals output from the first pressure sensor, the second pressure sensor, and the acceleration sensor of the inspection device of embodiment 2 (when there is no "rattle"); 10 is a flowchart showing the operation of the inspection device according to the second embodiment.

Below, an inspection device, an inspection method, and an inspection program according to embodiments will be described with reference to the drawings. The following embodiments are merely examples, and the embodiments can be combined as appropriate and each embodiment can be modified as appropriate.

Embodiment 1.
Fig. 1 is a functional block diagram showing a schematic configuration of an inspection device 1 according to the first embodiment. As shown in Fig. 1, the inspection device 1 includes a first pressure sensor 10, a second pressure sensor 20, a vibration state determination unit 31, and a notification unit 32. The vibration state determination unit 31 and the notification unit 32 are parts of an information processing device 30. The inspection device 1 is a device capable of carrying out the inspection method according to the first embodiment.

The inspection device 1 is a device that inspects the state of an object to be inspected. The object is, for example, a device having two or more structures and connecting parts such as bolts or screws that connect them. In the first embodiment, "inspection of the state of the object" refers to a judgment as to whether the object is in a "gripped vibration state" C2 in which the first pressure sensor 10 and the second pressure sensor 20 are swayed (i.e., vibrated) while the object is sandwiched and held between the first pressure sensor 10 and the second pressure sensor 20, or in a "gripped stationary state" C1 in which the first pressure sensor 10 and the second pressure sensor 20 are not swayed (i.e., not vibrated) while the object is sandwiched and held between the first pressure sensor 10 and the second pressure sensor 20. The vibration at this time may be either a shaking by a worker's hand or a shaking by the tip of a machine arm (a part corresponding to a human hand) such as a robot.

The first pressure sensor 10 and the second pressure sensor 20 are arranged, for example, on the pad surface of the fingertip of a glove, which is a glove-shaped holding member worn on the hand of a worker. The first pressure sensor 10 and the second pressure sensor 20 are held in the holding member. The holding member is a deformable member, and when the holding member is worn on a body part (e.g., a hand) of a person and an object is to be grasped, the first pressure-sensitive surface 11 of the first pressure sensor 10 and the second pressure-sensitive surface 21 of the second pressure sensor 20 face each other. When the holding member is a glove 40, the first pressure sensor 10 and the second pressure sensor 20 are arranged at the position of the thumb of the glove 40 and the positions of the fingers other than the thumb of the glove 40, respectively. In general, the first pressure sensor 10 is arranged on the pad surface of the fingertip of the thumb of the glove 40, and the second pressure sensor 20 is arranged on the pad surface of the fingertip of the index finger of the glove 40. The structure of the holding member is not limited to this.

Known pressure sensors can be used as the first pressure sensor 10 and the second pressure sensor 20. For example, a configuration is known in which a sensor element and a resistor element whose resistance value changes depending on the pressure (or force) applied to the sensor surface are used to measure a voltage generated by resistive voltage division, and the applied pressure is calculated based on the relationship between the measured voltage and the applied pressure. The sensor element may also be, for example, a capacitance sensor.

The vibration state determination unit 31 determines whether the state of the object 50 is a non-grasped state C0 in which the object 50 is not being grasped, a gripped stationary state C1 in which the object 50 is being grasped and stationary with the hand wearing the glove 40, or a gripped vibration state C2 in which the object 50 is being grasped and vibrated, based on the first electrical signal (i.e., output signal) P1 output from the first pressure sensor 10 and the second electrical signal (i.e., output signal) P2 output from the second pressure sensor 20. The notification unit 32 notifies the result of the determination by the vibration state determination unit 31.

The notification unit 32 transmits the judgment result of the vibration state judgment unit 31, i.e., information indicating the result of the inspection of the state of the target object 50, to a data management device that manages the inspection results, for example, as a notification signal. The notification unit 32 may also include a speaker and a display screen for providing the operator with a sound (for example, an electronic sound such as a buzzer) or a display indicating the inspection result.

Figure 2 is a plan view that shows a schematic example of an example in which the first pressure sensor 10 and the second pressure sensor 20 are provided in a glove 40, which is a glove-shaped holding member. Figure 3 is a side view that shows a schematic example of the inspection device 1. The glove 40 is worn on the hand, which is part of the worker's body. In this case, the inspection device 1 is a wearable inspection device. The shape of the glove 40 is not limited to that shown in the figure. The number of pressure sensors may be three or more. It is preferable that the first pressure sensor 10 and the second pressure sensor 20 are of the same standard, but they may be sensors of different standards or different types.

The first pressure sensor 10 has a first pressure-sensitive surface 11 and outputs a first electrical signal P1 corresponding to a first pressure F1 applied to the first pressure-sensitive surface 11. The second pressure sensor 20 has a second pressure-sensitive surface 21 and outputs a second electrical signal P2 corresponding to a second pressure F2 applied to the second pressure-sensitive surface 21.

Based on the first electrical signal P1 and the second electrical signal P2, the vibration state determination unit 31 determines whether the state of the object 50 is a non-grasped state C0 in which the object 50 is not being grasped, a grasped vibration state C2 in which the object 50 is sandwiched and grasped between the first pressure sensitive surface 11 and the second pressure sensitive surface 21 and the first pressure sensor 10 and the second pressure sensor 20 are being oscillated, or a grasped stationary state C1 in which the object 50 is sandwiched and grasped between the first pressure sensitive surface 11 and the second pressure sensitive surface 21 and the first pressure sensor 10 and the second pressure sensor 20 are not being oscillated.

Figure 4 is a diagram showing an example of the hardware configuration of the inspection device 1 according to embodiment 1. As shown in Figure 4, the information processing device 30 of the inspection device 1 has a processor 101 such as a CPU (Central Processing Unit), a memory 102 which is a storage device, a communication device 103, and an interface 104. The memory 102 is, for example, a semiconductor memory such as a RAM (Random Access Memory).

Each function of the information processing device 30 shown in FIG. 1 is realized, for example, by a processing circuit. The processing circuit may be dedicated hardware, or may be a processor 101 that executes a program (including an inspection program according to an embodiment) stored in the memory 102. The processing circuit may be configured using a microcomputer or a single-board computer including an analog/digital (AD) converter that acquires and converts the voltages output from the first pressure sensor 10 and the second pressure sensor 20. The information processing device 30 may be partially realized by dedicated hardware and partially realized by software or firmware. In this way, the processing circuit can realize each of the above-mentioned functions by hardware, software, firmware, or any combination of these.

2 and 3, the information processing device 30 including the vibration state determination unit 31 and the notification unit 32 is disposed on the globe 40, but the information processing device 30 may be disposed at a position away from the globe 40. In addition, the information processing device 30 may be configured to be distributed among multiple computers that can communicate with each other.

Figure 5 is a side view showing an ungrasped state C0 in which the object 50 is not being grasped. Figure 5 shows the ungrasped state C0 in which the first pressure sensitive surface 11 of the first pressure sensor 10 and the second pressure sensitive surface 21 of the second pressure sensor 20 are not in contact with the object 50. The object 50 has a structure in which members 51 and 52 are connected by connecting parts 53 and 54. The connecting parts 53 and 54 are, for example, screws or bolts.

Figure 6 is a side view showing a gripping stationary state C1 in which the object 50 is gripped. Figure 6 shows the gripping stationary state C1 in which the first pressure-sensitive surface 11 of the first pressure sensor 10 and the second pressure-sensitive surface 21 of the second pressure sensor 20 are in contact with the object 50. In Figure 6, the glove 40 is in a stationary state and not being shaken, so the first pressure F1 applied from the worker's thumb to the bottom surface of the object 50 via the first pressure sensor 10 and the second pressure F2 applied from the worker's index finger to the top surface of the object 50 via the second pressure sensor 20 are approximately constant values and are balanced with each other.

Figure 7 is a side view showing a gripping vibration state C2 in which the object 50 is gripped and shaken. Figure 7 shows a gripping vibration state C2 in which the first pressure-sensitive surface 11 of the first pressure sensor 10 and the second pressure-sensitive surface 21 of the second pressure sensor 20 are in contact with the object 50, and the first pressure sensor 10 and the second pressure sensor 20 are shaken in the D direction (upward and downward in the figure). Since the glove 40 is shaken, the first pressure F1 applied to the lower surface of the object 50 and the second pressure F2 applied to the upper surface of the object 50 change in response to the shaking, and the changes in the first pressure F1 and the second pressure F2 are in opposite phase to each other.

Figure 8 is a waveform diagram showing an example of the first and second electrical signals (also called "detection signals") P1, P2 output from the first pressure sensor 10 and the second pressure sensor 20 of the inspection device according to embodiment 1. In Figure 8, during the period from time 0 to time t1, the inspection device 1 is in the state shown in Figure 5, the glove 40 is in a non-gripping state C0 in which it is not touching the object 50, and no pressure is applied to either the first pressure sensor 10 or the second pressure sensor 20.

In Fig. 8, during the period from time t1 to time t2, the inspection device 1 is in the state shown in Fig. 6, in a gripping stationary state C1 in which the object 50 is clamped and gripped between the first pressure sensor 10 and the second pressure sensor 20 provided in the glove 40. At this time, as force is applied to both the first pressure sensor 10 and the second pressure sensor 20, the pressures synchronously indicate high values.

In FIG. 8, during the period from time t2 to time t3, the inspection device 1 is in a gripping vibration state C2 in which the first pressure sensor 10 and the second pressure sensor 20 provided in the glove 40 pinch and grasp the object 50, and the first pressure sensor 10 and the second pressure sensor 20 that pinch the object 50 are swayed in the D direction. As in the gripping state, pressure is applied and a high value is indicated. Furthermore, in the vibration operation, the applied force alternates between strong and weak, so the pressure waveform vibrates in synchronization with the vibration operation. When the first pressure sensor 10 and the second pressure sensor 20 face each other, the vibrations of the first pressure sensor 10 and the second pressure sensor 20 show opposite positive and negative changes. For convenience, this is referred to as the outputs of the first pressure sensor 10 and the second pressure sensor 20 being in opposite phase.

Figure 9 is a flowchart showing the operation of the inspection device 1. Figure 9 shows the processing of the vibration state determination unit 31. In step S11, the vibration state determination unit 31 determines whether the values of the output signals of both the first pressure sensor 10 and the second pressure sensor 20 are equal to or greater than a predetermined threshold value Th1. If the value of the output signal is equal to or greater than the threshold value Th1, the vibration state determination unit 31 advances the processing to step S12, and if the value of the output signal is less than the threshold value Th1, it determines that the inspection is not started and that the state is a non-grasping state C0.

In step S12, the vibration state determination unit 31 determines whether the first pressure sensor 10 and the second pressure sensor 20 are vibrating in opposite phases. If the vibration state determination unit 31 determines that they are vibrating in opposite phases, it determines that the inspection device 1 is in the gripping vibration state C2, and if it does not determine that they are vibrating in opposite phases, it determines that the inspection device 1 is in the gripping rest state C1.

The result of the determination according to the flowchart in Fig. 9 is notified by the notification unit 32. The notification unit 32 may, for example, display the result of the determination in text or may turn on a lamp corresponding to the result of the determination. The notification unit 32 may also transmit the result to an external computer.

In addition, the threshold value Th1 in step S11 is set in advance to make the gripping rest state C1 and the non-grip state C0 a distinguishable value. For example, a large amount of output data from the pressure sensor in each state can be collected, and a distinguishable boundary can be set statistically. As a statistical method, for example, a boundary surface calculated using a support vector machine known in the field of machine learning can be set as the threshold value Th1. As an example of a large amount of data, data collected by changing the worker, the part being worked on, the working posture, etc. can be used.

The determination of whether or not the vibrations are in antiphase in step S12 can be made in a number of ways. For example, it can be made as follows.

The output of the first pressure sensor 10 at time t is P1(t), and the output of the second pressure sensor 20 is P2(t). The offset amount is calculated based on the pressure values in the gripping stationary state C1 corresponding to the period from time t1 to time t2 in FIG. 8, and is corrected by subtraction. For example, the pressure value P1ac(t) obtained by subtracting the offset amount from the output value P1(t) of the first pressure sensor 10, and the pressure value P2ac(t) obtained by subtracting the offset amount from the output value P2(t) of the second pressure sensor 20 are calculated by equations (1) and (2).

In the gripping vibration state C2, that is, in the period from time t2 to time t3, if the absolute value of the difference between P1ac(t) and P2ac(t) is greater than a predetermined threshold value Thd, the vibration state determination unit 31 determines that the outputs of the first pressure sensor 10 and the second pressure sensor 20 are in opposite phase. If the absolute value of the difference is smaller than the predetermined threshold value Thd, the vibration state determination unit 31 determines that the outputs of the first pressure sensor 10 and the second pressure sensor 20 are not in opposite phase. The determination may be based on an instantaneous value or on a statistical quantity such as a standard deviation or variance. P1ac(t) can also be obtained by applying a high-pass filter designed in advance to remove the offset amount from P1(t). The vibration state determination unit 31 may also obtain a determination result for each section of a predetermined length and use the majority vote as the final determination result. The threshold value Thd is set in advance to a value that allows the gripping vibration state C2 and the gripping rest state C1 to be distinguished from each other. For example, a large amount of output data from the pressure sensor in each state can be collected, and a distinguishable boundary can be set statistically. As a statistical method, for example, a boundary surface calculated using a support vector machine known in the field of machine learning can be set as the threshold value Thd. In addition, as an example of a large amount of data, data collected by changing the worker, the part to be worked on, the working posture, etc. can be used.

As another method for determining whether vibrations are occurring in antiphase, the determination may be made based on the cross-correlation value C, for example, as shown in equation (3).

Equation (3) calculates the cross-correlation value C by inverting the positive and negative of one of the pressure values of the first pressure sensor 10 and the second pressure sensor 20 after offset correction. In other words, if the outputs of the first pressure sensor 10 and the second pressure sensor 20 after inverting the positive and negative of one of the pressure values are vibrating and similar, the cross-correlation value shows a large value. The vibration state determination unit 31 can determine that the cross-correlation value calculated in this manner is in antiphase when it is equal to or greater than a predetermined threshold value (first threshold value) Thc.

As another method of determining whether or not vibration occurs in antiphase, for example, the time series data of the output values of the first and second pressure sensors 10 and 20 may be regarded as a first-order sine wave, the phase may be calculated, and the determination may be made based on the phase difference. The vibration state determination unit 31 determines that the phase is antiphase when the phase difference is equal to or greater than a predetermined threshold (second threshold) Thp, and that the phase is not antiphase when the phase difference is smaller than the threshold Thp. There are several known methods for calculating the phase of time series data, and a common method is, for example, to perform a Fourier transformation on the waveform of the gripping vibration state C2 and refer to the phase at the frequency component with the largest amplitude. Another common method is to assume that the time series data is a first-order sine wave and calculate the amplitude, frequency, and phase using an autoregressive model.

With this configuration, it is possible to distinguish between a gripped rest state C1 and a gripped vibration state C2 when inspecting an object using the glove 40. In the work judgment system of Patent Document 1, a configuration for detecting a gripped state is described, but a configuration for detecting a gripped vibration state is not described. The inspection device 1, inspection method, and inspection program of embodiment 1 achieve an unprecedented effect of being able to distinguish between a gripped state and a vibration state.

Embodiment 2.
FIG. 10 is a functional block diagram showing a schematic configuration of the inspection device 2 according to the second embodiment. The inspection device 2 is a device capable of carrying out the inspection method according to the second embodiment. In FIG. 10, the same reference numerals as those shown in FIG. 1 are used for the same or corresponding components as those shown in FIG. 1. The inspection device 2 according to the second embodiment differs from the inspection device 1 according to the first embodiment in that it includes an acceleration sensor 60 that outputs a third electric signal (output signal) P3 corresponding to the acceleration generated in the object 50 and a fastening state determination unit 33 that determines the fastening state between the fastened members. The inspection device 2 may include a microphone 61 that collects sound instead of or in addition to the acceleration sensor 60.

The fastening state determination unit 33 determines that the object 50 has an insufficient fastening portion, i.e., that there is a "wobble", based on the amplitude of the third electrical signal (output signal) P3 output from the acceleration sensor 60 during the gripping vibration state C2. Specifically, the fastening state determination unit 33 determines that the object 50 has an insufficient fastening portion when the amplitude of the third electrical signal (output signal) P3 output from the acceleration sensor 60 during the gripping vibration state C2 is equal to or greater than a predetermined threshold value Tha.

Furthermore, the fastening state determination unit 33 may determine that the object 50 has an insufficient fastening portion based on the amplitude of the fourth electrical signal (output signal) P4 output from the microphone 61 during the gripping vibration state C2. Specifically, the fastening state determination unit 33 may determine that the object 50 has an insufficient fastening portion when the amplitude of the fourth electrical signal (output signal) P4 output from the microphone 61 during the gripping vibration state C2 is equal to or greater than a predetermined threshold value Thm.

Furthermore, the fastening state determination unit 33 may determine that the object 50 has an insufficient fastening portion based on the amplitude of the third electrical signal P3 output from the acceleration sensor 60 and the amplitude of the fourth electrical signal P4 output from the microphone 61 during the gripping vibration state C2. Specifically, the fastening state determination unit 33 may determine that the object 50 has an insufficient fastening portion when the amplitude of the third electrical signal P3 output from the acceleration sensor 60 is equal to or greater than a predetermined threshold value Tha and the amplitude of the fourth electrical signal P4 output from the microphone 61 is equal to or greater than a predetermined threshold value Thm during the gripping vibration state C2.

Figure 11 is a plan view that shows an example in which the first pressure sensor 10, the second pressure sensor 20, and the acceleration sensor 60 of the inspection device 2 are provided on the glove 40. Figure 12 is a side view that shows an example of the inspection device 2 when the object 50 is grasped. Since the object 50 is not sufficiently fastened, vibrations associated with "wobbling" occur in the object 50 when the hand is shaken and vibrated. In the second embodiment, in addition to the first pressure sensor 10 as a thumb pressure sensor and the second pressure sensor 20 as an index finger pressure sensor, the device is configured to include an acceleration sensor 60 that measures vibrations of the fingertips when the object 50 is shaken to enter the gripping vibration state C2.

Figure 13 is a diagram showing an example of the hardware configuration of the inspection device 2. In Figure 13, components that are the same as or correspond to those shown in Figure 4 are given the same reference numerals as those shown in Figure 4. The hardware configuration of the inspection device 2 differs from that of embodiment 1 in that it is equipped with an acceleration sensor 60. Furthermore, the inspection device 2 may be equipped with a microphone 61 that picks up sound instead of or in addition to the acceleration sensor 60.

Figure 14 is a waveform diagram showing an example of the first to third electrical signals (detection signals) P1, P2, and P3 output from the first pressure sensor 10, the second pressure sensor, and the acceleration sensor 60 of the inspection device 2 (when there is "rattle"). Figure 15 is a waveform diagram showing an example of the first to third electrical signals P1, P2, and P3 output from the first pressure sensor 10, the second pressure sensor, and the acceleration sensor 60 of the inspection device of embodiment 2 (when there is no "rattle").

14 and 15 show the response of the acceleration sensor 60 when the object 50 is vibrated during the period from time t2 to time t3. The responses of the first pressure sensor 10 and the second pressure sensor 20 are the same as those of the first and second pressure sensors of the first embodiment shown in FIG. 8. FIG. 14 shows an example of a response when the object 50 is not sufficiently fastened and "wobble" occurs. When a worker puts on the glove 40 and shakes the hand to vibrate it, vibrations associated with "wobble" are generated and transmitted to the acceleration sensor 60. FIG. 15 shows an example of a response when the object 50 is sufficiently fastened. The "wobble" that occurs when the glove 40 is put on and vibrated is very small, so no vibration occurs and no fluctuation is observed by the acceleration sensor 60.

Figure 16 is a flowchart showing the operation of the inspection device 2. In Figure 16, the same steps as those shown in Figure 9 are given the same reference numerals as those shown in Figure 9. Step S13 is a step corresponding to the processing of the fastening state determination unit 33. In a state in which the object 50 is vibrated during the period from time t2 to time t3, the fastening state determination unit 33 determines the presence or absence of "wobble", i.e., whether the equipment is sufficiently fastened, based on the response of the acceleration sensor 60. For example, the third electrical signal (the amplitude of the acceleration detection signal output from the acceleration sensor 60 is used as a feature, and if it is equal to or greater than the threshold value Tha, it is determined that there is "wobble" (insufficient fastening), and if it is less than the threshold value Tha, it is determined that there is no "wobble" (sufficient fastening).

The threshold value Tha is set in advance to a value that can distinguish between an insufficiently fastened state and a sufficiently fastened state. For example, a large amount of data from the acceleration sensor 60 in a sufficiently fastened state can be collected, and a distinguishable boundary can be set statistically. As a statistical method, for example, a one-class support vector machine (OCSVM) known in the field of machine learning can be used to calculate a boundary surface corresponding to the space of the sufficiently fastened state and set it as the threshold value Tha. In other words, this is synonymous with detecting an insufficiently fastened state as an outlier.

As an example of a large amount of data, data collected by changing the worker, the part being worked on, the working posture, etc. can be used. The feature amount may be determined based on an instantaneous value, or based on a statistical amount such as standard deviation or variance. Furthermore, the determination result may be output for each section of a predetermined length, and the majority vote may be used as the final determination result.

By configuring it in this manner, in addition to the effect of embodiment 1 of being able to determine the state in which an object is grasped and the state in which it is grasped and vibrated when inspecting an object using the glove 40, it also has the unprecedented effect of being able to determine whether the device is sufficiently fastened when vibration is applied.

In addition, the fastening state determination unit 33 may calculate the speed and displacement by integrating the measured acceleration over time, and if the speed or displacement is greater than a predetermined threshold, it may be determined that there is a "wobble". The method of calculating the speed and displacement by integrating the acceleration over time is widely known, but the DC component (offset) mainly caused by the inclination of the acceleration sensor 60 is added to the measured acceleration value, which causes a decrease in the accuracy of the speed and displacement calculated by time integration. In the second embodiment, the output value of the acceleration sensor 60 in the stationary state after detecting the grip stationary state C1 (i.e., the value of the third electrical signal) is considered to correspond to the DC component. That is, the DC component is calculated based on the output value of the acceleration sensor 60 in the grip stationary state C1, and then the DC component is subtracted from the value of the acceleration sensor 60 in the grip vibration state C2, and the speed and displacement (corresponding to the magnitude of the "wobble") can be calculated with high accuracy by performing time integration.

In addition, a one-axis acceleration sensor that detects only one axis may be used as the acceleration sensor 60 to calculate the amount of displacement that coincides with the axial direction of the sensor. Alternatively, a two-axis or three-axis acceleration sensor may be used as the acceleration sensor 60 to calculate the amount of displacement based on a composite vector of the displacement.

In addition, the result of judging whether the components constituting the equipment are sufficiently fastened to each other may be correlated with the fastening conditions of the object 50 (bolt tightening force, bolt material, etc.). The judgment result and the fastening conditions are sent to a computer that communicates with the outside, and the computer analyzes under what fastening conditions the equipment is sufficiently fastened. The computer then periodically inspects the fastening state of the object and repeats the analysis. From these analysis results, it is possible to investigate whether the equipment is fastened with more fastening force than necessary. Fastening may loosen over time, and if the equipment is fastened with more fastening force than necessary, deterioration of the equipment may progress at the boundary between the equipment and the bolt. Therefore, from these analysis results, the progress of deterioration of the fastened part can be diagnosed.

1, 2 Inspection device, 10 First pressure sensor, 11 First pressure-sensitive surface, 20 Second pressure sensor, 21 Second pressure-sensitive surface, 30 Information processing device, 31 Vibration state determination unit, 32 Notification unit, 33 Fastening state determination unit, 50 Object, 60 Acceleration sensor, 61 Microphone, F1 First pressure, F2 Second pressure, P1 First electrical signal, P2 Second electrical signal, P3 Third electrical signal, P4 Fourth electrical signal, C0 Non-gripping state, C1 Gripping stationary state, C2 Gripping vibration state.

Claims (9)

An inspection device for inspecting a state of an object, comprising:
a first pressure sensor having a first pressure-sensitive surface and configured to output a first electrical signal corresponding to a first pressure applied from the object to the first pressure-sensitive surface;
a second pressure sensor having a second pressure sensitive surface and outputting a second electrical signal corresponding to a second pressure applied from the object to the second pressure sensitive surface;
a vibration state determination unit that determines, based on the first electrical signal and the second electrical signal, whether the state of the object is a gripping vibration state in which the object is sandwiched and gripped between the first pressure sensitive surface and the second pressure sensitive surface and the first pressure sensor and the second pressure sensor are vibrating, or a gripping stationary state in which the object is sandwiched and gripped between the first pressure sensitive surface and the second pressure sensitive surface and the first pressure sensor and the second pressure sensor are not vibrating, and determines that the object is in the gripping vibration state when a cross-correlation value between the first electrical signal and the second electrical signal is equal to or greater than a predetermined first threshold value;
An inspection device comprising: a deformable holding member that holds the first pressure sensor and the second pressure sensor,
The testing device according to claim 1 , wherein the first pressure-sensitive surface and the second pressure-sensitive surface face each other when the holding member is attached to a part of the human body. The holding member is a glove,
3. The inspection device according to claim 2, wherein the first pressure sensor and the second pressure sensor are disposed at a position of the thumb of the glove and at positions of the fingers other than the thumb of the glove, respectively. 4. The inspection device according to claim 1, wherein the vibration state determination unit determines whether a state of the object is the grip vibration state or the grip stationary state based on an amplitude of the first electrical signal and an amplitude of the second electrical signal. 5. The inspection device according to claim 1, wherein the vibration state determination unit determines that the object is in the grip vibration state when a difference in phase between the first electrical signal and the second electrical signal is equal to or greater than a predetermined second threshold value. a microphone that outputs a fourth electrical signal corresponding to the sound;
a fastening state determination unit that determines whether or not there is a rattle in a fastened portion of the object based on the fourth electrical signal in the gripping vibration state;
The inspection device according to claim 1 , further comprising: 7. The inspection device according to claim 1, further comprising a notification unit that notifies a result of the determination by the vibration state determination unit. a first pressure sensor having a first pressure-sensitive surface and configured to output a first electrical signal corresponding to a first pressure applied from an object to the first pressure-sensitive surface;
a second pressure sensor having a second pressure sensitive surface and outputting a second electrical signal corresponding to a second pressure applied from the object to the second pressure sensitive surface;
An inspection method for inspecting a state of an object, the method being carried out by an inspection apparatus comprising:
an inspection method comprising: a step of determining, based on the first electrical signal and the second electrical signal, whether the state of the object is a gripping vibration state in which the object is clamped and grasped between the first pressure sensitive surface and the second pressure sensitive surface and the first pressure sensor and the second pressure sensor are vibrating, or a gripping stationary state in which the object is clamped and grasped between the first pressure sensitive surface and the second pressure sensitive surface and the first pressure sensor and the second pressure sensor are not vibrating; and determining that the object is in the gripping vibration state if a cross-correlation value between the first electrical signal and the second electrical signal is equal to or greater than a predetermined first threshold value . a first pressure sensor having a first pressure-sensitive surface and configured to output a first electrical signal corresponding to a first pressure applied from an object to the first pressure-sensitive surface;
a second pressure sensor having a second pressure sensitive surface and outputting a second electrical signal corresponding to a second pressure applied from the object to the second pressure sensitive surface;
an information processing unit of an inspection device that inspects a state of the object,
an inspection program which executes a step of determining, based on the first electrical signal and the second electrical signal, whether the state of the object is a gripping vibration state in which the object is clamped and grasped between the first pressure sensitive surface and the second pressure sensitive surface and the first pressure sensor and the second pressure sensor are vibrating, or a gripping stationary state in which the object is clamped and grasped between the first pressure sensitive surface and the second pressure sensitive surface and the first pressure sensor and the second pressure sensor are not vibrating, and determining that the object is in the gripping vibration state if a cross-correlation value between the first electrical signal and the second electrical signal is equal to or greater than a predetermined first threshold value .

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