JP7002078B2 - Tactile detection device - Google Patents

Description

The present invention relates to a tactile sensation detection device capable of quantifying and evaluating the tactile sensation when a sample is touched.

Generally, when a human touches an object, the sensation changes greatly depending on the reaction force or friction received from the object. For example, when a human touches a hard plate, the reaction force received by the finger reacts sensitively to the pressing force of the finger, and the reaction force increases. On the other hand, when a soft cloth or sponge is touched, the pressing force of the finger is increased. The reaction force slowly increases against. In addition, when a human touches an object by tracing it, the tactile sensation changes depending on the state of the surface of the object and the viscosity with the human finger. Therefore, by quantitatively quantifying these tactile sensations, the state of the surface of the sample can be evaluated.

However, conventionally, when quantifying the human tactile sensation, the reaction force and waveform of the finger are measured (Patent Document 1 etc.), or the Coulomb friction coefficient is calculated and quantified from the reaction force against the pressing force of the finger. Since it was only possible to do something like that, it was difficult to evaluate the tactile sensation based on the viscosity when touching an object with a finger.

Japanese Unexamined Patent Publication No. 5-332917

Therefore, an object of the present invention is to provide a tactile sensation detection device capable of quantifying and evaluating the tactile sensation received from a sample in consideration of not only the reaction force but also the tactile sensation due to the movement of a human finger.

That is, in order to solve the above problems, the present invention uses a plate on which a sample is placed, a plurality of load detection sensors for detecting the load applied to the plate, and the load detection sensor, and a finger contacts the sample. It is detected by the load calculating means for detecting the load in the XYZ direction, the moving state calculating means for calculating the moving speed of the load position applied to the sample from the loads applied to the plurality of load detecting sensors, and the load calculating means. It is provided with a tactile value calculating means for quantifying the tactile sensation between the finger and the sample from the applied load and the moving speed calculated by the moving state calculating means.

With this configuration, not only the Coulomb friction coefficient based on the load but also the viscous friction coefficient based on the moving speed and the like can be calculated, so that the sensation closer to the human touch can be quantified and evaluated. It will be like.

Further, in such an invention, the load detection sensor is provided at at least three positions apart from the plate, preferably near the four corners of the plate.

With this configuration, the Coulomb friction coefficient can be calculated based on the load from the load detection sensor, and the load position can be calculated by this load detection sensor, so the viscous friction coefficient based on the moving state can also be calculated. You will be able to.

At this time, preferably, when the moving state is calculated by the moving state calculating means, the load position of the finger is calculated from the load of the plurality of load detection sensors at predetermined time intervals, and the moving speed is calculated from the moving time of the load position . calculate.

With this configuration, the Coulomb friction coefficient based on the load and the viscous friction coefficient based on the moving state can be calculated at the same time using the same load detection sensor.

Furthermore, vibration information is also extracted using the load detection sensor.

With this configuration, in addition to the Coulomb friction coefficient and the viscous friction coefficient, it is possible to extract and evaluate information that is closer to the human touch by extracting vibration information. Here, as the vibration information, information such as a spectrum can be extracted in addition to the vibration waveform.

According to the present invention, a plate on which a sample is placed, a plurality of load detection sensors for detecting the load applied to the plate, and the load detection sensor are used to load in the XYZ direction when a finger comes into contact with the sample. The load calculating means for detecting the above, the moving state calculating means for calculating the moving speed of the load position applied to the sample from the loads applied to the plurality of load detecting sensors, and the load detected by the load calculating means and the moving state calculation. Since the tactile value calculating means for quantifying the tactile sensation between the finger and the sample from the moving speed calculated by the means is provided, not only the Coulomb friction coefficient based on the load but also the viscous friction coefficient based on the moving speed is provided. Can also be calculated, and it becomes possible to evaluate a sensation closer to the human touch.

Schematic side view of a tactile detection device showing an embodiment of the present invention. Schematic diagram of the tactile sensation detection device in the same form Functional block diagram in the same form Functional block diagram in other embodiments Flow chart of tactile detection device in the same form

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

The tactile sensation detection device 1 in this embodiment is capable of quantifying and evaluating the tactile sensation of a flat sample 8 such as a cloth, and the sample 8 is placed as shown in FIGS. 1 and 2. The plate 2 is provided with a flat plate 2 and a load detection sensor 3 provided near the four corners of the plate 2. And, characteristically, when the sample 8 placed / fixed on the plate 2 is moved by tracing while pressing with a finger, the vertical downward load of the plate 2 and the plane direction of the plate 2 are followed. The load is detected, and the COP, which is the pressed portion of the finger, is obtained from the load detection sensors 3 provided near the four corners. Then, the movement speed of the finger is detected from the movement time of the COP, and the Coulomb friction coefficient, the viscous friction coefficient, etc. are calculated from the load in the vertical downward direction, the load in the plane direction of the plate 2, and the movement speed. The tactile sensation can be quantified. Hereinafter, the tactile sensation detection device 1 according to the present embodiment will be described in detail.

First, the plate 2 is made of a square or rectangular transparent body. The sample 8 can be placed on the surface of the plate 2, and the sample 8 is attached to the surface of the plate 2 in a state of being pulled in a plane by using a fixing tool 81 so that the sample 8 cannot be moved. The fixing tool 81 may be a holding tool such as a clip, or may be an adhesive body such as double-sided tape. Further, if the plate 2 is made transparent here, the back surface side of the sample 8 can be photographed with a camera from below the plate 2, and not only the COP is detected by the load detection sensor 3 but also the finger is detected by the camera. It will also be possible to take pictures of the position and calculate the movement speed.

The load detection sensor 3 is provided near the four corners of the plate 2 and is capable of detecting a load in the XYZ directions orthogonal to each other, a moment around the XYZ axis, and the like. Here, the vertical direction of the plate 2 will be referred to as the Z axis, and the direction along the plane of the plate 2 will be described as the X axis and the Y axis. As such a load detection sensor 3, a strain gauge type sensor, a piezoelectric sensor, or the like can be used, but here, a strain gauge type load detection sensor 3 suitable for long-term monitoring is used. do. These output values from the load detection sensor 3 are output to the load calculating means 4 and the moving state calculating means 5, respectively, and the load due to the pressing of the finger, the moving state of the finger, and the like are calculated there.

In the load calculation means 4, among the signals output from each load detection sensor 3, the total load in the Z-axis direction and the total load in the XY plane direction are calculated. When calculating the load in the Z-axis direction, Pz is calculated by summing the loads in the Z-axis direction from each load detection sensor 3, and when calculating the load applied in the XY plane direction, the load in the X-axis direction is calculated. The total Px and the total Py of the load in the Y-axis direction are calculated, and their resultant force is calculated as Pxy. Then, these loads Pz and Pxy in the Z-axis direction are stored for each sampling time.

On the other hand, the moving state calculating means 5 calculates COP, which is the coordinates of the pressed portion of the finger, from the load in the Z-axis direction output from each load detection sensor 3. When calculating the COP, which is the load position of this finger, the output value of the load detection sensor 3 on the right front provided below the plate 2 is PFR (Front Right), and the output value of the load detection sensor 3 on the left front is PFL. (Front Left), when the output value of the load detection sensor 3 on the right rear side is PBR (Back Right) and the output value of the load detection sensor 3 on the left rear side is PBL (Back Left), the following is performed according to the moment balance equation. COP (Gx, Gy) is calculated.

<Equation 1>
Gx = (PFR + PBR) x Lx / (PFR + PFL + PBR + PBL)
Gy = (PFR + PFL) x Ly / (PFR + PFL + PBR + PBL)

Here, Lx and Ly are the distances of the load detection sensors 3 in the X direction and the Y direction.

Then, the coordinates of the COP are calculated for each sampling time using this equation 1, and the moving distance of the COP is calculated from the difference in the sampling times. Then, the movement speed of the COP is calculated by dividing the movement distance by the sampling time. Although the movement speed of the COP is calculated here, the acceleration of the movement may also be detected. When detecting such an acceleration, it is preferable to extract the moving speed when the acceleration is zero in the sampling time before and after, that is, when the finger is moved at a constant speed.

The Pz and Pxy calculated by the load calculation means 4 and the movement speed V calculated by the movement state calculation means 5 are output to the tactile value calculation means 6, and an index for the tactile sensation is calculated there. .. When the tactile sensation is quantified and output by the tactile sensation value calculating means 6, the following relational expression is used.

<Equation 2>

Pxy = μPz + γV

Here, "μ" is the Coulomb friction coefficient, and "γ" is the viscous friction coefficient. The Coulomb friction coefficient μ is integrated with the load in the normal direction of the plate 2, and the viscosity coefficient is integrated with the moving speed of the finger which is an object.

Then, based on Pxy, Pz, and V of at least two sampling times, the unknown Coulomb friction coefficient μ and viscous friction coefficient γ are calculated from Equation 2. When calculating these coefficients, if the sampling time is long, the Coulomb friction coefficient μ and the viscous friction coefficient γ may be calculated for each sampling time, and the average value thereof may be calculated. Then, these Coulomb friction coefficient μ and viscous friction coefficient γ are stored in the storage unit 7 so that they can be output as an index for the tactile sensation of the sample 8.

Next, a method of using the tactile detection device 1 configured in this way will be described with reference to FIG.

First, when detecting the tactile sensation of the sample 8, the sample 8 is placed on the surface of the plate 2 and pulled and fixed in a wrinkle-free state, and the output value of each load detection sensor 3 is initially set to zero in that state. (Step S1).

Then, after the initial setting is completed in this way, the surface of the sample 8 is pressed with a finger and traced in the plane direction of the plate 2. Then, the load in the XYZ axis direction is detected from the load detection sensors 3 provided near the four corners of the plate 2 (step S2), and is output to the load calculation means 4 and the moving state calculation means 5 (step S3).

In the load calculation means 4, first, the total load in the Z-axis direction from each load detection sensor 3 is calculated to calculate Pz (step S4). Further, in parallel with this, the total load in the X-axis direction and the total load in the Y-axis direction are calculated, and the value of Pxy, which is the resultant force of these, is calculated (step S4).

Further, the moving state calculating means 5 calculates COP, which is the coordinates of the pressed portion of the finger, from the load in the Z-axis direction output from each load detection sensor 3 using Equation 1 (step S5).

Then, the COP is calculated for each sampling time, and the finger movement speed V is calculated from the time and the distance of the COP (step S6).

Then, using this moving speed V and Pz and Pxy previously calculated by the load calculating means 4, the Coulomb friction coefficient μ and the viscous friction coefficient γ are calculated using Equation 2 for each of a plurality of sampling times (step S7). ).

Then, the Coulomb friction coefficient μ and the viscous friction coefficient γ calculated in this way are stored in the storage unit 7 and output as the tactile sensation of the sample 8 so that they can be evaluated.

As described above, according to the above embodiment , the finger is described by using the plate 2 on which the sample 8 is placed, a plurality of load detection sensors 3 for detecting the load applied to the plate 2, and the load detection sensor 3. A load calculating means 4 for detecting a load in the XYZ direction when in contact with a sample 8, and a moving state calculating means 5 for calculating a moving speed of a load position applied to the sample 8 from the loads applied to the plurality of load detecting sensors 3. A tactile value calculating means 6 for quantifying the tactile sensation between the finger and the sample 8 from the load detected by the load calculating means 4 and the moving speed calculated by the moving state calculating means 5 is provided. Therefore, not only the Coulomb friction coefficient based on the load but also the viscous friction coefficient based on the moving state can be calculated, and it becomes possible to evaluate a feeling closer to the human touch.

Further, since the load detection sensor 3 is provided near the four corners of the plate 2, the load can be detected by the load detection sensor 3 and the Coulon friction coefficient can be calculated, and the load can be calculated by the load detection sensor 3. The position can be calculated, and the coefficient of viscous friction based on the moving state can also be calculated.

Further, when the moving state is calculated by the moving state calculating means 5, the COP is calculated from the loads of the plurality of load detection sensors 3 at predetermined time intervals, and the moving state is calculated from the moving time of the COP. Using the same load detection sensor 3, the Coulomb friction coefficient based on the load and the viscous friction coefficient based on the moving state can be calculated at the same time.

The present invention is not limited to the above embodiment, and can be carried out in various embodiments.

For example, in the above embodiment, the load detection sensor 3 can be used to calculate Pxy, Pz, V, and the like, but the load detection sensor 3 can also be used to extract the vibration waveform of the load along the XY plane direction. This may be used as an index of tactile sensation. In this case, since the vibration waveform differs depending on the moving speed of the finger, the vibration waveform of time-load (Pxy) may be standardized using the speed V, and the vibration waveform at the same speed may be calculated. Then, as shown in FIG. 4, the vibration waveform may be frequency-analyzed using the frequency analysis means 9, and the frequency having a spectrum exceeding a predetermined threshold value may be stored as an index for tactile sensation.

Further, in the above embodiment, the load detection sensors 3 are provided near the four corners of the plate 2, but if the coordinates of the finger and the load in the XYZ direction can be detected, at least three or more non-linear positions are provided. The load detection sensor 3 may be provided in the vehicle.

Further, in the above embodiment, the Coulomb friction coefficient and the viscous friction coefficient between the sample 8 and the finger are calculated, but by moving the sample 8 on the plate 2, the sample 8 and the plate 2 are separated from each other. The Coulon friction coefficient, the viscous friction coefficient, the vibration waveform, and the like may be calculated.

1 ... Tactile detection device 2 ... Plate 3 ... Load detection sensor 4 ... Load calculation means 5 ... Movement state calculation means 6 ... Tactile value calculation means 7 ... Storage unit 8 ...・ ・ Specimen 81 ・ ・ ・ Fixture 9 ・ ・ ・ Frequency analysis means

Claims (4)

A plate on which the sample is placed and
Multiple load detection sensors that detect the load applied to the plate,
A load calculation means for detecting a load in the XYZ direction when a finger comes into contact with the sample using the load detection sensor, and a load calculation means.
A moving state calculation means for calculating the moving speed of the load position applied to the sample from the load applied to the plurality of load detection sensors, and
A tactile value calculating means for quantifying the tactile sensation between the finger and the sample from the load detected by the load calculating means and the moving speed calculated by the moving state calculating means.
A tactile detection device characterized by being equipped with. The tactile detection device according to claim 1, wherein the load detection sensor is provided at at least three positions apart from the plate. The tactile sensation according to claim 1, wherein the moving state calculating means calculates a finger load position from the load of the plurality of load detection sensors at predetermined time intervals, and calculates a moving speed from the moving time of the load position . Detection device. The tactile sensation detection device according to claim 1, wherein the vibration waveform is also extracted by using the load detection sensor.

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