JP7653292B2 - Skin or cosmetic evaluation device - Google Patents

Description

The present invention relates to a skin or cosmetic evaluation device technology.

As a device for evaluating human skin, simulated skin that imitates human skin, or cosmetics, there is one that evaluates human skin or cosmetics using vibration information generated when an artificial finger made to imitate a human finger is slid (for example, Patent Document 1).

JP 2019-095263 A

In the case of Patent Document 1, only vibration information generated on the surface of the artificial finger can be obtained, and the physical properties related to the touch of human skin or the touch of cosmetics are evaluated based on this information alone, so the results obtained from the evaluation were limited. In addition, since vibration also changes depending on the normal force (pressing force), it is effective to measure the normal force, but since the artificial finger does not have a built-in force sensor, it is sometimes difficult to measure vibration and normal force simultaneously or at a constant normal force.
Furthermore, frictional force, which is also important for tactile sensation, could not be measured.

The present invention has been made in consideration of the above problems, and relates to a skin or agent evaluation device technology that includes a contactor having flexibility that mimics the flexibility of a human finger, a contact surface that is the outer surface of the contactor and is brought into contact with a subject, and a force sensor that is provided on the inside of the contactor and measures the force received from the subject via the contact surface. In this specification, skin evaluation refers to evaluation of the subject's skin or simulated skin that mimics human skin for non-medical purposes, and includes evaluation that can be performed by anyone other than an expert.

The present invention relates to a skin or agent evaluation device that includes a contactor having flexibility that mimics the flexibility of a human finger, a contact surface on the outer surface of the contactor that is brought into contact with a subject, and a force sensor that is provided on the inside of the contactor and measures the force received from the subject via the contact surface.

The present invention also includes a first acquisition step of bringing a contact surface, which is the outer surface of a contactor having flexibility simulating the flexibility of a human finger, into contact with a test specimen or a test specimen coated with a predetermined agent, and acquiring first contact surface information generated on the contact surface and first internal information generated inside the contactor via the contact surface; and a second acquisition step of bringing a contact surface of another contactor having a different flexibility from the contactor into contact with the test specimen or a test specimen coated with the predetermined agent, and acquiring second contact surface information generated on the contact surface and second internal information generated inside the contactor via the contact surface. The present invention relates to a method for evaluating skin or an agent, the method including: a second acquisition step; a first calculation step of calculating a first feature amount occurring on the surface of the contact surface based on the acquired first internal information; a second calculation step of calculating a second feature amount occurring on the surface of the contact surface based on the acquired second internal information; a first evaluation step of evaluating the feel of the skin of the subject or characteristics of the agent based on the first feature amount and the contact surface first information; and a second evaluation step of evaluating the feel of the skin of the subject or characteristics of the agent based on the second feature amount and the contact surface second information.
The present invention also relates to a skin or agent evaluation system comprising a contactor having flexibility that mimics the flexibility of a human finger, a contact surface that is the outer surface of the contactor and is brought into contact with a subject, and a force sensor that is provided on the inside of the contactor and measures a force received from the subject via the contact surface, an acquisition means for acquiring a value measured by the force sensor, and an evaluation means for evaluating the subject or the agent based on the value acquired by the acquisition means.

The technology provided by the present invention makes it possible to provide a device that can evaluate the feel of a subject's human skin or an agent.

FIG. 1A is a cross-sectional image of the contact 100 when worn on a finger; FIG. 1B is a diagram showing the position at which the force sensor 40 is provided relative to the lower layer 30; and FIG. 1C is a diagram showing the force sensor 40. 1A is a diagram showing the shape of the contact surface 11, in which (a) is a diagram showing the position where the groove 13 shown in (c) is cut out, (b) is a diagram showing the position where the groove 13 shown in (c) is formed, and (c) is a diagram showing the shape of the groove 13. 2 is a flow chart illustrating the method. 1 is a conceptual diagram showing how a six-axis force sensor is used to measure the force acting on a contact surface 11 of a contactor 100. FIG. 5 is a graph comparing estimated values calculated from values measured by the force sensor 40 with actual values measured by a six-axis force sensor, where (a) is a graph showing values of Fx, and (b) is a graph showing values of Fz. 11 is a graph showing an error between an estimated value calculated from a measurement value by a force sensor 40 and an actual measurement value by a six-axis force sensor. 11 is a graph showing the measurement results using the contact 100(S). 13 is a graph showing the measurement results using the contact 100(H). 11 is a graph showing the measurement results using the contact 100(A). 13 is a graph showing the measurement results using the contact 100(N). 13 is a graph showing another measurement result using the contact 100(A). 13 is a graph showing another measurement result using the contact 100(N). 4 is a graph showing the measurement results using the contact 100. FIG. 4 is a block diagram of a system 400 for evaluating human skin, skin modeled after human skin, or an agent.

Embodiments of the present invention will be described below with reference to the drawings. Note that similar components in each drawing are given similar reference numerals, and descriptions will be omitted as appropriate.

<Evaluation device for human skin, simulated skin that resembles human skin, or agents>
The skin or agent evaluation device 200 of this embodiment (hereinafter may be referred to as this device) includes a contactor 100 having flexibility that mimics the flexibility of a human finger, a contact surface 11 that is the outer surface of the contactor 100 and is brought into contact with a subject, and a force sensor 40 that is provided on the inside of the contactor 100 and measures the force received from the subject via the contact surface 11. The contactor 100 is a member having flexibility that mimics the flexibility of a human finger. The contact surface 11 is the outer surface of the contactor 100 and is the part that is brought into contact with the subject. The force sensor 40 is a sensor that is provided on the inside of the contactor 100 and measures the force received from the subject via the contact surface 11.

The inventors of the present invention have found that in the past technology, for example, in Patent Document 1, only vibration information generated by the sliding movement of the artificial finger could be obtained. In addition, the only information that could be obtained was vibration information transmitted from the artificial finger generated by the sliding movement, so the information was limited. The vibration information transmitted from the artificial finger was used to evaluate the feel of human skin or cosmetics and physical properties related to the feel, so the evaluation results were limited. In particular, it was understood that the shape of the skin surface and the magnitude of friction caused by touching affect the tactile sensation generated when touching the skin, but these could not be used to evaluate the feel, and it was concluded that there was room for improvement.
Therefore, in this device, forces in multiple directions received from the specimen via contact surface 11, which is the outer surface of contactor 100 and is the part that comes into contact with the specimen, are acquired by a force sensor 40 provided inside contactor 100.

The present device will now be described in more detail with reference to FIG.
FIG. 1 is a diagram showing the entire evaluation device 200. In this embodiment, as shown in FIG. 1, the evaluation device 200 is mainly composed of a contactor 100 having flexibility that imitates the flexibility of a human finger. The contactor 100 is provided with a contact portion 12 having a contact surface 11 that is the outer surface of the contactor 100 and is brought into contact with a subject. The contact portion 12 includes an upper layer 10 (also called an outer contact portion) including the contact surface 11, and an intermediate layer 20 (also called an inner contact portion) provided on the opposite side of the contact surface 11. A lower layer 30 (also called a core portion) is provided inside the intermediate layer 20 provided on the opposite side of the contact surface 11 of the contact portion 12. That is, the contactor 100 is configured with a multi-layer structure of an upper layer (surface layer) 10, an intermediate layer 20, and a lower layer 30. The contactor 100 is not limited to a three-layer structure, and may be a two-layer structure in which the upper layer 10 and the intermediate layer 20 are configured as one layer, or may be configured with four or more layers. A force sensor 40 is provided on the inside of the lower layer 30, which is the inside of the contactor 100, i.e., on the opposite side to the contact portion 12, for measuring a force received from the subject via the contact surface 11. The contactor 100 is also provided with a vibration sensor 50 for measuring vibrations occurring on the contact surface 11. In this embodiment, the vibration sensor 50 is provided by wrapping it around the contactor 100. Note that the specific configuration of the vibration sensor 50 is not limited as long as it can measure vibrations occurring on the contact surface 11. The vibration sensor 50 can be realized by, for example, a piezoelectric body, a strain gauge, an acceleration sensor, or the like. The vibration sensor is preferably in the form of a sheet or film having a wide detection area in order to detect vibrations propagated via a vibration propagation portion.

The contactor 100 is made of a flexible material that mimics the flexibility of a human finger. Here, mimicking the flexibility of a human finger means that the contactor has flexibility similar to the characteristics of the softness and hardness of a human finger, and is made of an elastomer such as soft rubber or gel. In order to make the characteristics such as softness and hardness similar to those of a human finger, the upper layer (surface layer) 10 of the contactor 100 is made of silicone, and the intermediate layer 20 is made of urethane gel, but this is not limited to this, and the upper layer 10 and the intermediate layer 20 may be made of the same material or different materials, and the material may be a flexible material such as silicone, urethane gel, or rubber. Since the hardness of the finger pad of a human finger varies from person to person, in this embodiment, multiple types of intermediate layers 20 with different hardness levels are provided, so that the intermediate layer 20 is preferably made of a material whose hardness is easy to adjust. By configuring a plurality of intermediate layers 20 (inner contact portions) having different flexibility to be detachable from the lower layer 30 (also called a core portion), it is possible to easily perform measurements using the contactor 100 assuming various hardnesses and softnesses of human fingers. Note that, although the intermediate layers 20 are formed to have different flexibility in this embodiment, the upper layer 10 on which the contact surface 11 is provided may be formed to have different flexibility.
In addition, the construction of a plurality of contact parts 12 with different flexibilities so as to be detachable from the core part (lower layer 30) includes, in addition to the above, the construction in which the upper layer 10 (outer contact part) and the intermediate layer 20 (inner contact part) are integrated and detachable from the lower layer 30 (core part), the construction in which the intermediate layer 20 (inner contact part) is integrated with the lower layer 30 (core part) so that the upper layer 10 (outer contact part) is detachable from the intermediate layer 20 (inner contact part), and the construction in which the upper layer 10 (outer contact part) and the intermediate layer 20 (inner contact part) are individually detachable. Each construction also has the following effects. The upper layer 10 (outer contact part) and the intermediate layer 20 (inner contact part) are integrated, so that they can be easily attached and detached from the lower layer 30. By configuring the intermediate layer 20 (inner contact portion) to be integrated with the lower layer 30 (core portion) and the upper layer 10 (outer contact portion) to be detachable from the intermediate layer 20 (inner contact portion), the upper layer 10 can be indirectly detachable from the lower layer 30, and the hardness of only a part of the upper layer 10 can be easily changed, so that various hard and soft contacts 100 can be easily formed. By configuring the upper layer 10 (outer contact portion) and the intermediate layer 20 (inner contact portion) to be detachable individually, the combination of the upper layer 10 and the intermediate layer 20 can also be changed, so that various hard and soft contacts 100 can be easily formed. In addition, a member having a different flexibility may be detachable from the upper layer 10, in addition to the upper layer 10. How to configure the members to be detachable may be determined by considering the ease of processing the members, the ease of attaching and detaching the members, and the operability of the user when attaching and detaching the members.
For the fingerprint surface shape, a fingerprint-modeled groove 13 is formed on the surface of the contact 100. In addition, ASA resin is used as the material for the lower layer 30, but this is not limiting. The lower layer 30 has a role of protecting the force sensor 40, and in this embodiment, since the shape is modeled after a human finger, it is preferable to use a material that takes into consideration weather resistance, rigidity, hardness, processability, impact resistance, bending fatigue, etc.
The contact surface 11, which is the outer surface of the contactor 100 and which is brought into contact with the subject, is preferably provided on the outer surface of the contactor 100, particularly on a part of the contactor 100 which corresponds to the finger pad, modeled after a human finger, taking into consideration that a person will touch the subject with the pad of his or her finger when checking the tactile sensation of the subject.
The force sensor 40, which measures the force received from the subject through the contact surface 11 provided on the inside of the contactor 100, is preferably provided at a position corresponding to the back side of the contact surface 11. This is because it is desired to configure the force received from the subject through the contact surface 11, such as the direction and strength of the force received from the subject when the contact surface 11 of the contactor 100 touches the subject. The force sensor 40 uses a sensor that can capture the resistance change corresponding to the strain (displacement) generated by the force. The force sensor 40 may be of any configuration, such as a strain gauge type, a capacitance type, a pressure-sensitive conductivity, a piezoelectric effect, a piezoresistive effect, light, sound, a magnetic field, or a contact resistance. In this embodiment, a multi-axis sensor is used as the force sensor 40. And, by providing the force sensor 40 and the vibration sensor 50 on the contactor 100, it is possible to detect with both sensors at the same time and use it for a composite evaluation.

As shown in FIG. 1, the contactor 100 has a hollow structure and is detachable from a human finger. This makes it easier to touch the subject in the same way as when a human actually touches the subject with his or her finger (such as the force applied to the subject and the movement when touching the subject), making it possible to measure a force similar to that when a human touches the subject with his or her finger. Instead of making the contactor 100 hollow, for example, the contactor 100 may be integrated into a control rod. In this way, for example, the contactor 100 can be installed in a specified device and the contactor can be moved to touch the subject at a specified speed with a specified force for measurement.

Next, the force sensor 40 will be described with reference to FIGS. 2(a), 2(b) and 2(c).
The force sensor 40 provided in this embodiment is a force sensor 40 (multi-axis sensor) having a shape as shown in FIG. 2(c). FIG. 2(a) is a cross-sectional image diagram when the contactor 100 is attached to a finger, and shows the positional relationship between the contactor 100, the force sensor 40, and a human finger. As is clear from FIG. 2(a), the force sensor 40 embedded in the lower layer 30 is provided at a position that contacts the finger pad of the human finger when the contactor 100 is attached to the human finger. Therefore, when the contactor 100 is attached to the human finger, the force sensor 40 contacts the finger pad of the human finger. FIG. 2(b) shows the position at which the force sensor 40 is provided on the lower layer 30. As shown in FIG. 2(b), the force sensor 40 is provided so as to be embedded in the lower layer 30.
When the contact surface 11 of the contactor 100 provided with the force sensor 40 touches the test subject, the force sensor 40 can measure the force received from the test subject via the contact surface 11. Since the force sensor 40 uses a multi-axis sensor, it can measure the force generated by the action of rubbing the contactor 100 against the test subject and the force generated by the action of pushing and releasing the contactor 100 against the test subject.

Next, the surface shape of the contact surface 11 of the contactor 100 will be described with reference to Figures 3(a), 3(b) and 3(c). A plurality of grooves 13 are formed on the surface of the contactor 100, imitating the fingerprints of human fingers. Figure 3(c) shows an enlarged view of the dotted line portion of Figure 3(a). Also, the grooves 13 shown in Figure 3(c) are formed in the range of the two-dot chain line of the contactor 100 in Figure 3(b). A plurality of upper layers 10 (outer contact portions) having different depths or intervals or having the grooves 13 shown in Figure 3(c) are formed detachably with respect to the intermediate layer 20 (inner contact portion). By configuring in this way, measurements can be easily performed using the contactor 100 assuming various surface shapes of human fingers. In particular, in this embodiment, the intermediate layer 20 is formed to have different flexibilities, and the surface shape of the contact surface 11 of the upper layer 10 (outer contact portion) is made different and detachable, so that the combination of the difference in flexibility of the contactor 100 and the difference in surface shape of the contact surface 11 of the contactor 100 can be easily changed, and the contactor 100 that meets the measurement conditions can be easily configured. In this embodiment, the groove 13 is formed in the upper layer 10 on which the contact surface 11 is provided, but a member in which the groove 13 is formed separately from the upper layer 10 may be made detachable from the upper layer 10. In addition, the shape of the groove 13 may be any shape, such as a horizontal groove, an ellipse, or a spiral groove, in addition to the vertical groove shown in FIG. 3(c).

Next, a description will be given of the surface properties of the contact surface 11 of the contactor 100. The surface properties referred to here particularly refer to characteristics related to the mechanical properties that arise when the artificial finger comes into contact with an object, such as slipperiness and adhesion.
In this embodiment, one contactor 100(N) has a contact surface 11 made of the silicone material of the upper layer 10 as is, and the other contactor 100(A) has a contact surface 11 made of the silicone material of the upper layer 10 coated with nitrocellulose. The area where the nitrocellulose is coated on the contact surface 11 may be the same as the area (within the two-dot chain line) where the groove 13 is formed as shown in FIG. 3(b). By coating the nitrocellulose, the contact surface 11 becomes smoother than that of 100(N). In this way, by configuring the multiple upper layers 10 (outer contact parts) of the contact surface 11 of the contactor 100 to be detachable from the intermediate layer 20 (inner contact part), measurements can be easily performed using the contactor 100 assuming various surface textures of human fingers. In particular, in this embodiment, the intermediate layer 20 is formed to have different flexibility, and the surface properties of the contact surface 11 of the upper layer 10 (outer contact portion) are made different and detachable, so that the combination of the difference in flexibility of the contactor 100 and the difference in surface shape of the contact surface 11 of the contactor 100 can be easily changed, and the contactor 100 that meets the measurement conditions can be easily configured. In this embodiment, nitrocellulose is applied to the upper layer 10 on which the contact surface 11 is provided, but a member coated with nitrocellulose separately from the upper layer 10 may be made detachable from the upper layer 10. In this embodiment, nitrocellulose is applied to change the surface properties of the contact surface 11, but this is merely an example, and is not limited to this as long as the surface properties of the contact surface 11 can be changed.

<Method of evaluating human skin, simulated skin that resembles human skin, or agents>
Next, a method for evaluating skin or an agent using this device (hereinafter, sometimes referred to as this method) will be described.

The subject to be contacted with the contact surface 11, which is the outer surface of the contactor 100 that may mimic the flexibility of a human finger, or the subject to be coated with a specific agent may be anything that the contactor 100 can touch, but in this embodiment, it is human skin or artificial skin. In addition to bare skin, skin includes bare skin on which a specific agent described below has been applied. In other words, contacting the contactor 100 with the skin includes not only the case where the contactor 100 comes into direct contact with bare skin, but also the case where the contactor 100 comes indirectly into contact with bare skin via a coating film of a specific agent applied to the skin. The location of the human skin, i.e., the part of the body, does not matter.
When evaluating the tactile sensation of a specific agent, it is preferable to evaluate a part of the skin that does not have any unevenness such as warts or acne scars. This is because it is difficult to evaluate whether the tactile sensation when the contactor 100 is in contact with the skin is due to the specific agent or the shape of the skin. However, this is not limited to the above, for example, when it is desired to evaluate by tactile sensation whether the unevenness is covered (whether the skin surface becomes flat) by applying a specific agent to uneven skin. It is preferable to determine the skin surface to be evaluated according to the conditions to be evaluated. In addition, artificial skin is an artificial simulation of the skin surface and has properties similar to human skin. In this embodiment, unless otherwise specified, the skin is the skin of a human face, particularly the area near the cheek.

Examples of the specified agent include topical skin preparations to be applied to the skin, cosmetics, and sheet-type skin care cosmetics, such as lotions, milky lotions, creams, beauty serums, massage packs, packs, lip balms, eye care sheets, mouth sheets, pack masks, sheet-type lotions, and sheet-type makeup removers; cleansing agents such as soaps and cleansers; makeup agents such as foundations, makeup bases, liquid foundations, oil-based foundations, powder foundations, concealers, control colors, eye shadows, blushers, lipsticks, lip glosses, lip liners, and body décolleté cosmetics; and UV protection cosmetics such as sunscreen milky lotions, sunscreen gels, and sunscreen creams, but are not limited to these.

Bringing the contact surface 11, which is the outer surface of the contactor 100, which has flexibility that mimics the flexibility of human fingers, into contact with a test subject or a test subject coated with a specific agent means touching the test subject (skin) with the contact surface 11, which is the outer surface of the contactor 100. In this embodiment, as shown in FIG. 1, a user wears the contactor 100 on the user's finger. The test subject, for example, the skin on the user's face, is touched through the contact surface 11, which is the outer surface of the contactor 100 worn on the finger. The contact surface 11 is brought into contact with the skin on the face by sliding it over the skin surface of the face or by gently pressing and releasing it. When evaluating facial skin, it is usually preferable to touch it with the same motion as when the user touches his or her own facial skin.

The first contact surface information generated on the contact surface 11 is the amount of force mechanically generated on the contact surface 11 when the contact surface 11 is brought into contact with the subject, and examples of such information include the magnitude of elastic force, the amount of current generated due to the displacement of the skin, the voltage value, and the amount of vibration. In this embodiment, the first contact surface information is particularly the amount of force generated when the surface shape of the contact surface 11 (e.g., a fingerprint) affects the surface shape of the subject when the contactor 100 is slid. In this embodiment, the vibration generated by sliding the contactor 100 is acquired by the vibration sensor 50. The same applies to the second contact surface information.
The first internal information generated through the contact surface 11 is the amount of force received from the subject through the contact surface 11 when the contact surface 11 is brought into contact with the subject, and examples of the force include the magnitude of elastic force, the amount of current generated due to the displacement of the skin, the voltage value, and the amount of vibration. In this embodiment, the force received from the subject through the contact surface 11 is particularly the amount of force that affects the contact surface 11 getting caught or slipping when the contactor 100 is slid. In this embodiment, the force generated when the contactor 100 is slid is acquired by the force sensor 40. The same applies to the second internal information.
As described above, the flexible contactor 100 modeled after a human finger having different flexibility is one of a plurality of types of contactors having different hardness levels of the intermediate layer 20. In this embodiment, the measurement is performed using the contactor 100(S) and the contactor 100(H) having a harder flexibility than the contactor 100(S).
In this embodiment, the contact surface first information and the internal first information are information obtained by contacting the contactor 100 (S) with the test specimen, and the contact surface second information and the internal second information are information obtained by contacting the contactor 100 (H) with the test specimen.

Calculating the first feature amount occurring on the surface of the contact surface 11 based on the acquired internal first information means estimating the amount of mechanically generated force (first feature amount) occurring on the surface of the contact surface 11 using the internal first information, since the acquired internal first information is a value measured by the force sensor 40 provided inside the contact surface 11. In this embodiment, in the first calculation step, the frictional force occurring on the surface of the contact surface 11 is estimated. In addition, in this embodiment, since the force sensor 40 uses a multi-axis sensor, a horizontal force (hereinafter, sometimes referred to as Fx) and a vertical force (hereinafter, sometimes referred to as Fz) with respect to the contact surface 11 are estimated. In addition, the first feature amount also includes a value calculated by calculating the horizontal force (Fx) and the vertical force (Fz) with respect to the estimated contact surface 11. The same applies to the second feature amount.
Evaluating the texture of the subject's skin or the characteristics of an agent based on the first characteristic amount and the first contact surface information means making an evaluation using the first characteristic amount and the first contact surface information, such as outputting a graph plotted in a coordinate system including a first axis indicating the first contact surface information and a second axis indicating the first characteristic amount, and comparing with data obtained by measuring the texture of multiple types of subjects in advance using the contact 100. The same applies to the case where the texture of the subject's skin or the characteristics of an agent is evaluated based on the second characteristic amount and the second contact surface information.

The tactile sensation of the subject's skin refers to the sensation felt when the subject's skin is touched with the contactor 100, and may be, for example, sticky, refreshing, moist, viscous, moist, dry, firm, elastic, soft, sticky, plump, smooth, close contact, rich, skin-friendly, or uneven, but is not limited to these sensations as long as they are produced by sliding, pressing, or releasing the contactor 100 that is in contact with the skin surface. Here, the "sticky sensation" refers to the sticky, adhesive sensation that sticks to the finger when the finger is in contact with the skin surface. The "refreshing sensation" refers to the smooth, refreshing sensation that does not stick to the skin surface when the finger is in contact with the skin surface. The "moist sensation" refers to the slightly damp, smooth sensation that occurs when the finger is in contact with the skin surface. "Sticky" refers to the feeling that a finger sticks to the skin surface when it is touched. "Moist" refers to the feeling that there is a moderate amount of moisture when a finger touches the skin surface. "Dry" refers to the feeling that the skin surface feels rough when a finger touches the skin surface. "Firm" refers to the feeling that the skin is taut and stiff when a finger touches the skin surface. "Elastic" refers to the feeling that the skin bounces back without sinking when a finger touches the skin surface. "Hard" refers to the degree to which the skin deforms when a finger touches the skin surface. "Sticky" refers to the feeling that the finger sticks to the skin surface when it is touched. "Soft" refers to the feeling that the finger sticks to the skin surface and bounces back when a finger touches the skin surface. "Fluffy" refers to a refreshing feeling that is slightly elastic and not sticky when the skin surface is touched with a finger. "Smooth" refers to the feeling that the finger moves smoothly when the finger is touched with the skin surface. "Adhesion" refers to the feeling that the cosmetic adheres to the skin when applied to the skin. "Rich" refers to the feeling that the cosmetic spreads on the skin while feeling its weight in the hand when applied to the skin. "Skin compatibility" refers to the feeling that the cosmetic blends with the skin when applied to the skin. "Uneven" refers to the sense of the shape of the surface when the finger is touched with the skin surface.

Evaluation of an agent means evaluating the feel of the agent itself when it is applied to the skin surface and the physical properties of the agent that produce the feel. The feel of the agent itself can be sticky, refreshing, moist, sticky, moist, dry, firm, elastic, soft, sticky, plump, smooth, close contact, rich, skin-friendly, etc. Each feel is as described above. The physical properties of the agent that produce the feel include the adhesion and moisture content of the skin surface, and the elasticity and viscoelasticity of the skin surface or internal skin tissue. "Adhesiveness" refers to the stickiness of the skin surface, which is caused by a specific agent, sebum, sweat, dirt, etc. "Moisture content" refers to the moisture present on the skin surface, which is caused by a specific agent, sweat, etc. It also refers to the amount of moisture contained in the internal skin tissue (e.g., the dermis). "Elasticity" refers to the hardness of the skin and affects the internal tissues of the skin (e.g., collagen). "Viscoelasticity" refers to the speed at which deformation progresses when force is applied to the skin, and is influenced by, for example, the compositional characteristics and structure of the internal tissues of the skin (stratum corneum and others).

Next, the process flow of this method will be described with reference to Fig. 4. Note that the process flow shown below is merely an example, and the order of the processes is not limited to this.
Step S100 is a process of bringing the contactor 100 (S) into contact with the skin of the face of the subject, and acquiring first internal information acquired by the force sensor 40 and first contact surface information acquired by the vibration sensor 50. Here, the first internal information and the first contact surface information are information acquired simultaneously when the contact surface 11 of the contactor 100 touches the subject.

Step S110 is a process of calculating the first feature quantity occurring on the surface of the contact surface 11 based on the acquired first internal information. In this embodiment, Fx (shear force), Fz (normal force), and the friction coefficient are calculated as the first feature quantities.

Step S120 is a process of evaluating the texture of the subject's skin or the characteristics of the agent based on the first feature and the first contact surface information. In this embodiment, a graph is output plotted in a coordinate system including a first axis indicating the first contact surface information and a second axis indicating the friction coefficient calculated from the values of Fx and Fz of the first feature.

Step S130 is a process of contacting the contactor 100(H) with the skin of the face of the subject, and acquiring the second internal information acquired by the force sensor 40 and the second contact surface information acquired by the vibration sensor 50. Here, the second internal information and the second contact surface information are information acquired simultaneously when the subject is touched by the contact surface 11 of the contactor 100. As described above, the contactor 100(H) is a contactor 100 that is more flexible than the contactor 100(S) used in step S110.

Step S140 is a process of calculating the second feature quantities occurring on the surface of the contact surface 11 based on the acquired second internal information. In this embodiment, Fx (shear force), Fz (normal force), and the friction coefficient are calculated as the second feature quantities.

Step S150 is a process for evaluating the texture of the subject's skin or the characteristics of the agent based on the second feature amount and the second contact surface information. In this embodiment, a graph is output plotted in a coordinate system including a first axis indicating the second contact surface information and a second axis indicating the friction coefficient calculated from the values of Fx and Fz of the second feature amount.

Ｆは推定値、Ｓは力センサ４０（多軸センサ）の信号、ｉはｘ軸、ｙ軸、ｚ軸の何れかを示す。
すなわち、上記単回帰式は、内部第１情報を用いて単回帰分析より取得した第１単回帰式であって、内部第１情報を説明変数とし、第１特徴量を目的変数とする。同様に、接触子１００（Ｈ）の力センサ４０から検出した内部第２情報を用いて単回帰分析より第２単回帰式を取得する。
＜重回帰式＞

Ｆは推定値、Ｓは力センサ４０（多軸センサ）の信号、ｉ、ｊはｘ軸、ｙ軸、ｚ軸の何れかを示す。
すなわち、上記重回帰式は、内部第１情報を用いて重回帰分析より取得した第１重回帰式であって、内部第１情報を説明変数とし、第１特徴量を目的変数とする。同様に、接触子１００（Ｈ）の力センサ４０から検出した内部第２情報を用いて重回帰分析より第２重回帰式を取得する。
これらの回帰式によって推定される値が接触面１１に生じる力とどの程度誤差があるか否かを以下の方法で検証した。 The values of Fx and Fz calculated from the internal first information will be described.
In this embodiment, as described above, the internal first information is a value detected by the force sensor 40 embedded inside the contactor 100. Therefore, the value detected by the force sensor 40 is not the actual value of the force acting on the contact surface 11. Therefore, the force acting on the contact surface 11 is estimated, and the tactile sensation of the subject's skin touched by the contactor 100 and the physical properties of the agent are evaluated using the estimated value.
The force acting on the contact surface 11 is calculated, for example, from a value detected by the force sensor 40 (corresponding to the first internal information) by a statistical means or by an estimation process performed by statistical estimation (corresponding to the first estimation process). At this time, the value detected by the force sensor 40 may be a value obtained by contacting the contact surface 11 of the contactor 100 once, but since there is a large variance in the values obtained by contacting once, it is preferable to use a value obtained by contacting multiple times.
A method for estimating the force acting on the contact surface 11 using a simple regression equation or a multiple regression equation will be described below. However, other methods such as random forest, support vector regression, or deep learning methods such as recurrent neural network (RNN) or long short term memory (LSTM) may also be used, and the estimation processing method is not limited.
Data obtained by sliding the contact 100 on the subject in a predetermined direction was obtained multiple times, and a regression equation was derived from the obtained data by the least squares method. Here, obtaining multiple times may mean obtaining data multiple times from one subject, obtaining data once from multiple subjects, or obtaining data multiple times from multiple subjects. The more data there are, the more preferable it is because the more the variation is suppressed. In addition, when obtaining data multiple times from one subject, it is assumed that the data is obtained at a predetermined interval, and the predetermined interval in this case is an interval such as an action of tapping multiple times in succession, and is in seconds or less. The regression equations derived were a simple regression equation calculated using one each of the Fx component, the Fy component, and the Fz component, and a multiple regression equation calculated using all of the Fx component, the Fy component, and the Fz component.
<Simple regression equation>

F indicates an estimated value, S indicates a signal from the force sensor 40 (multi-axis sensor), and i indicates any one of the x-axis, y-axis, and z-axis.
That is, the above-mentioned simple regression equation is a first simple regression equation obtained by simple regression analysis using the first internal information, in which the first internal information is an explanatory variable and the first feature amount is a response variable. Similarly, a second simple regression equation is obtained by simple regression analysis using the second internal information detected from the force sensor 40 of the contact 100(H).
<Multiple regression equation>

F is an estimated value, S is a signal from the force sensor 40 (multi-axis sensor), and i and j indicate either the x-axis, y-axis, or z-axis.
That is, the multiple regression equation is a first multiple regression equation obtained by multiple regression analysis using the first internal information, in which the first internal information is an explanatory variable and the first feature amount is a response variable. Similarly, a second multiple regression equation is obtained by multiple regression analysis using the second internal information detected from the force sensor 40 of the contact 100(H).
The extent to which there is an error between the values estimated by these regression equations and the force acting on the contact surface 11 was verified by the following method.

5, the contactor 100 slides the test object 150 placed on the six-axis force sensor 160, and the six-axis force sensor 160 detects the force generated on the contact surface 11. At this time, data from the force sensor 40 is also detected in addition to data from the six-axis force sensor 160. This data acquisition was performed ten times, and the regression equation was derived using values from nine sets of force sensors 40 (multi-axis sensors) to estimate the values of Fx and Fz.
6A is a graph plotting the Fx value estimated by the simple regression equation, the multiple regression equation, and the value detected by the six-axis force sensor 160. The X-axis indicates time, and the Y-axis indicates the Fx value. As is clear from FIG. 6A, the Fx value estimated by the simple regression equation, the multiple regression equation, and the value detected by the six-axis force sensor 160 were not significantly different.
6B is a graph plotting the Fz value estimated by the simple regression equation, the multiple regression equation, and the value detected by the six-axis force sensor 160. The X-axis indicates time, and the Y-axis indicates the Fx value. As is clear from FIG. 6B, there was not much difference between the Fz value estimated by the simple regression equation, the value estimated by the multiple regression equation, and the value detected by the six-axis force sensor 160.
Next, the root-square error was calculated for the Fx and Fz values estimated by the simple regression equation and the multiple regression equation for the values of nine sets of force sensors 40 (multi-axis sensors) among the data acquired by the above data acquisition, and the measured values by the six-axis force sensor 160. The X-axis in FIG. 7 indicates the type of force, and the Y-axis indicates the value of the root-square error. Here, the estimated values by the simple regression equation and the estimated values by the multiple regression equation were compared for two types of contactors 100, namely, contactor 100(S) and contactor 100(H), which have different hardnesses of the contactors 100. Here, data from the sliding section where the normal force of the six-axis force sensor 160 exceeds 0.05 N was used, but the range (section) of the data used is not limited to this.
As is clear from Figure 7, the estimated values of Fx and Fz obtained by the multiple regression equation have less error with the six-axis force sensor and are more accurate than the estimated values obtained by the simple regression equation. From these verification results, it can be said that the values of Fx and Fz specified using the values detected by the force sensor 40 are almost the same as the actual values detected by the six-axis force sensor.

In this way, the values of Fx and Fz estimated from the values detected by the force sensor 40 installed inside the contactor 100 are close to the actual measured values of Fx and Fz generated on the contact surface 11, so it can be said that it is effective to use these estimated values to evaluate human skin, simulated skin that imitates human skin, or agents.

図８には、接触子１００（Ｓ）で被検体を１０回接触した際の値を示す。Ｘ軸は接触面１１に生じる振動を振動センサ５０で検出した振動強度を示す。Ｙ軸は力センサ４０により検出した値から、接触面１１生じたと推定されるＦｘの値およびＦｚの値から算出した摩擦係数を示す。なお、摺動させた区間のうち、中心時間から前後０．１５（秒）（すなわち、合わせて０．３（秒））間のデータを使用したが、使用するデータの範囲（区間）はこれに限らない。図９には、接触子１００（Ｈ）で被検体を１０回接触した際の値を示す。Ｘ軸は接触面１１に生じる振動を振動センサ５０で検出した振動強度を示す。Ｙ軸は力センサ４０により検出した値から、接触面１１に生じたと推定されるＦｘの値およびＦｚの値から算出した摩擦係数（Ｆｘ／Ｆｚ）を示す。なお、摺動させた区間のうち、中心時間から前後０．１５（秒）（すなわち、合わせて０．３（秒））間のデータを使用したが、使用するデータの範囲（区間）はこれに限らない。
図８および図９より以下のことがわかる。同時に計測された振動強度と摩擦係数とを用いて評価することで、異なる被検体を測り分けられることがわかる。具体的には、例えば、被検体Ｂおよび被検体Ｃのように、表面の粗さはあまり変わらないが、硬度が異なる被検体を測り分けたい場合は、硬めの接触子１００（Ｈ）を用いればよい。また、被検体Ｅおよび被検体Ｆのように、表面の粗さが異なり、硬度があまり変わらない被検体を測り分けたい場合は、軟らかめの接触子１００（Ｓ）を用いればよい。すなわち、接触子１００の可撓性の硬軟によって複数種類の被検体の分離精度が異なることを利用することで、被検体の測り分けを行うことができる。これは、例えば、評価対象とする被検体に応じて接触子１００の種類（硬軟）を選択することで、被検体の測り分けを行うことに活用できる。 Next, a plurality of test specimens (six types, A to F) with different surface properties were contacted with the contact 100 (S) and the contact (H) with different flexibility, and the tactile sensation of the test specimens was evaluated.
Table 1 shows the roughness and hardness of several specimens A to F having different surface properties.

FIG. 8 shows values when the contactor 100 (S) contacts the subject 10 times. The X-axis shows the vibration intensity detected by the vibration sensor 50 of the vibration occurring on the contact surface 11. The Y-axis shows the friction coefficient calculated from the values of Fx and Fz estimated to have occurred on the contact surface 11 from the values detected by the force sensor 40. Note that, among the sliding sections, data was used from 0.15 (seconds) before and after the center time (i.e., 0.3 (seconds) in total), but the range (section) of data used is not limited to this. FIG. 9 shows values when the contactor 100 (H) contacts the subject 10 times. The X-axis shows the vibration intensity detected by the vibration sensor 50 of the vibration occurring on the contact surface 11. The Y-axis shows the friction coefficient (Fx/Fz) calculated from the values of Fx and Fz estimated to have occurred on the contact surface 11 from the values detected by the force sensor 40. Of the sliding section, data between 0.15 seconds before and after the center time (i.e., a total of 0.3 seconds) was used, but the range (section) of data to be used is not limited to this.
The following can be seen from FIG. 8 and FIG. 9. It can be seen that different specimens can be measured by evaluating using the vibration intensity and friction coefficient measured at the same time. Specifically, for example, when it is desired to measure specimens having different hardnesses but not much different surface roughnesses, such as specimens B and C, a harder contactor 100 (H) can be used. Also, when it is desired to measure specimens having different surface roughnesses but not much different hardnesses, such as specimens E and F, a softer contactor 100 (S) can be used. That is, by utilizing the fact that the separation accuracy of multiple types of specimens differs depending on the hardness or softness of the flexibility of the contactor 100, it is possible to measure the specimens. This can be utilized, for example, to measure the specimens by selecting the type (hardness or softness) of the contactor 100 according to the specimen to be evaluated.

Next, a plurality of specimens (three types: A, D, and F) with different surface properties were contacted with the contactor 100(N) and the contactor 100(A) with different surface properties, and the tactile sensation of the specimens was evaluated. Here, the contactor 100(N) has a contact surface 11 that is not treated, that is, the contact surface 11 is made of silicone material, which is the material of the upper layer 10, and the contactor 100(A) has a contact surface 11 that is coated with nitrocellulose. Therefore, the contactor 100(A) has a better slipperiness of the contact surface 11 than the contactor 100(N). In order to verify how the difference in the surface properties of the contactor 100 affects the evaluation results, the same hardness level of the contactor 100 was used.
Among the multiple specimens A to F shown in Table 1, specimens A, D, and F were used for the evaluation.

Fig. 10 shows values when the contactor 100 (N) contacts the test object 10 times. The X-axis shows the vibration intensity of the vibration generated on the contact surface 11 detected by the vibration sensor 50. The Y-axis shows the friction coefficient calculated from the values of Fx and Fz estimated to have occurred on the contact surface 11 from the values detected by the force sensor 40. Fig. 11 shows values when the contactor 100 (A) contacts the test object 10 times. The X-axis shows the vibration intensity of the vibration generated on the contact surface 11 detected by the vibration sensor 50. The Y-axis shows the friction coefficient calculated from the values of Fx and Fz estimated to have occurred on the contact surface 11 from the values detected by the force sensor 40.
The following can be seen from FIG. 10 and FIG. 11. It can be seen that different specimens can be measured by evaluating using the vibration intensity and friction coefficient measured at the same time. Specifically, for example, when the separation accuracy of specimen F is to be improved, the contactor 100 (A) coated with nitrocellulose can be used. Also, when it is desired to measure specimens A and D, the contactor 100 (N) that has not been treated for smoothness can be used. That is, by utilizing the fact that the separation accuracy of multiple types of specimens differs depending on the smoothness of the contactor 100, it is possible to measure the specimens. For example, this can be utilized to measure the specimens by selecting the type (smoothness) of the contactor 100 according to the specimen to be evaluated.

Next, multiple subjects (skin shape replicas) with different surface shapes were contacted with contacts 100(N) and 100(A) with different surface properties, and the tactile sensation of the subjects was evaluated. The skin shape replicas used in this embodiment were a skin shape replica with a relatively smooth surface and a skin shape replica with larger irregularities such as pores. Then, by comparing the feel with contacts 100 with contact surfaces 11 with different properties as shown below, it is possible to distinguish between these skin shape replicas with different surface shapes.

12 shows values when the contactor 100 (N) contacts the test object multiple times (about 10 times). The X-axis shows the vibration intensity of the vibration generated on the contact surface 11 detected by the vibration sensor 50. The Y-axis shows the friction coefficient calculated from the values of Fx and Fz generated on the contact surface 11 from the values detected by the six-axis force sensor 160. FIG. 13 shows values when the contactor 100 (A) contacts the test object multiple times (about 10 times). The X-axis shows the vibration intensity of the vibration generated on the contact surface 11 detected by the vibration sensor 50. The Y-axis shows the friction coefficient calculated from the values of Fx and Fz generated on the contact surface 11 from the values detected by the six-axis force sensor 160.
The following can be seen from Figures 12 and 13. It can be seen that different specimens can be measured by evaluating using the vibration intensity and friction coefficient measured at the same time. Specifically, the use of a contactor 100 (A) coated with nitrocellulose increases the accuracy of vibration separation, and the use of a contactor 100 (N) that has not been treated for smoothness increases (can emphasize) the accuracy of friction separation. This can be used to measure specimens by selecting the type (smoothness) of the contactor 100 according to the specimen to be evaluated, for example.

Next, the contactor 100 was pressed against a plurality of test specimens of different hardness (hard urethane rubber and soft urethane rubber) to evaluate the tactile sensation of the test specimens. The hard urethane rubber used for the test specimens had a hardness of 23, and the soft urethane rubber had a hardness of 8. Here, the evaluation was performed using the value of Fz estimated by the force sensor 40. Note that the estimated value Fz here was a value estimated by a simple regression equation, but it may be a value estimated by a multiple regression equation. Also, data from a section where the estimated Fz value exceeded 0.05 N was used, but the range (section) of data used is not limited to this.
Fig. 14 shows the average and standard deviation of Fz values estimated three times by pressing the contact 100 against the subject. The X-axis shows the type of subject, and the Y-axis shows the estimated Fz value. As can be seen from Fig. 14, the hardness of the subject can be evaluated by using the Fz value estimated from the value detected by the force sensor 40 of the contact 100. Therefore, it can be said that a multifaceted evaluation can be performed by performing a composite evaluation using the value of the vibration sensor 50, which can be detected simultaneously with the force sensor 40 of the contact 100.

<Skin or agent evaluation system>
Next, an evaluation system 400 including the above-described evaluation device 200 will be described.
15 shows a block diagram of an evaluation system 400 including an evaluation device 200. The evaluation system 400 includes an information processing terminal 300 including an acquisition means 310 for acquiring sensor information measured by the evaluation device, a calculation means 320 for calculating a feature amount from the acquired information, an evaluation means 330 for performing an evaluation based on the calculated feature amount and the acquired sensor information, and an output means 340 for outputting an evaluation result, in addition to the evaluation device 200. The information processing terminal 300 includes an input device such as a keyboard or a pointing device, an arithmetic processing device, a storage unit, and the like. The evaluation system 400 evaluates human skin, a simulated skin modeled after human skin, or an agent by the above-mentioned method for evaluating human skin, a simulated skin modeled after human skin, or an agent.

<Modification>
The present invention is not limited to the above-described embodiment, and various modifications and improvements are possible.

In this embodiment, the contactor 100 is attached to a finger to perform measurements, but the contactor 100 may not be attached to a finger, but may be attached to a specified measuring rod and held between a person's fingers to perform measurements. Alternatively, the measuring rod may be attached to a specified tool and moved with a constant force and at a constant speed to perform measurements. In particular, by moving with a constant force and at a constant speed to perform measurements, it is possible to perform measurements that minimize errors due to the way of touching.

In this embodiment, measurements were taken on bare skin, but a specific agent may be applied to the surface of the face and the feel of the skin surface may be measured. Also, a skin care agent such as a mask sheet soaked in a specific agent may be placed (attached) to the surface of the face and its feel may be measured. In this way, the feel of an agent placed (attached) on the surface of the face during use can be evaluated.

In this embodiment, measurements were taken when nitrocellulose was applied to the contact surface 11 of the contactor 100 with the same hardness and softness level of flexibility and when it was not applied. However, this is not limited to this, and measurements may be taken with both the hardness and softness level of the flexibility of the contactor 100 and the presence or absence of application of nitrocellulose. In this way, by selecting the type of contactor 100 (hardness and surface slipperiness) according to the specimen to be evaluated, it can be used to measure the specimen.

In this embodiment, the contactor 100 has flexibility that mimics the flexibility of a human finger, but the shape, such as thickness, may also be mimicked. Taking into consideration the user of this device, it is preferable that the shape, such as thickness, of a human finger mimics the thickness of an average adult finger.

In this embodiment, a force sensor 40 is provided inside the contactor 100 to measure the force received from the subject via the contact surface 11. However, in addition to this, for example, an inertial measurement unit (IMU sensor) may also be provided inside the contactor 100, and the values of Fx and Fz may be calculated (estimated) including the signal detected by the inertial measurement unit. By correcting the influence of the attitude of the contactor 100 using the detection signal from the inertial measurement unit, the estimation accuracy of the values of Fx and Fz can be improved, making it possible to perform a highly accurate evaluation.

Reference Signs List 10 Upper layer 11 Contact surface 12 Contact portion 13 Groove 20 Middle layer 30 Lower layer 40 Force sensor 50 Vibration sensor 100 Contactor 150 Test object 160 Six-axis force sensor 200 Evaluation device 300 Information processing terminal 310 Acquisition means 320 Calculation means 330 Evaluation means 340 Output means 400 Evaluation system

Claims (16)

A contactor having flexibility that mimics the flexibility of a human finger;
a contact surface which is an outer surface of the contact and is brought into contact with a test object;
a force sensor provided inside the contact and configured to measure a force received from the test object via the contact surface ;
The contactor is a hollow structure that can be attached to and detached from a human finger . The contacts include
a contact portion having the contact surface;
a core portion provided on the opposite side of the contact surface of the contact portion,
The skin or agent evaluation device according to claim 1 , wherein the force sensor is provided on an opposite side of the core portion to the contact portion. The skin or agent evaluation device according to claim 2, characterized in that a plurality of contact parts having mutually different flexibility are configured to be detachable from the core part. The skin or agent evaluation device according to claim 2 or 3, characterized in that the contact part comprises an outer contact part including the contact surface and an inner contact part on the core part side. The skin or agent evaluation device according to claim 4, characterized in that the outer contact parts, each having a different surface shape, are configured to be detachable from the inner contact part. The skin or agent evaluation device according to claim 4 or 5, characterized in that the outer contact parts, each having a different surface property from the other, are configured to be detachable from the inner contact part. A contactor having flexibility that mimics the flexibility of a human finger;
a contact surface which is an outer surface of the contact and is brought into contact with a test object;
a force sensor provided inside the contact and configured to measure a force received from the test object via the contact surface ;
The contacts include
a contact portion having the contact surface;
a core portion provided on the opposite side of the contact surface of the contact portion,
A skin or agent evaluation device, in which the force sensor is provided on the opposite side of the core portion to the contact portion . a first acquiring step of bringing a contact surface, which is an outer surface of a contactor having flexibility simulating the flexibility of a human finger, into contact with a test subject or a test subject to which a predetermined agent has been applied, and acquiring first contact surface information generated on the contact surface and first internal information generated inside the contactor via the contact surface;
a second acquiring step of contacting a contact surface of another contact having a flexibility different from that of the contact with the test specimen or the test specimen to which the predetermined agent is applied, and acquiring second contact surface information generated on the contact surface and second internal information generated inside the contact via the contact surface;
a first calculation step of calculating a first feature amount occurring on the surface of the contact surface based on the acquired first internal information;
a second calculation step of calculating a second feature amount occurring on the surface of the contact surface based on the acquired second internal information;
a first evaluation step of evaluating a feel of the skin of the subject or a property of the agent based on the first feature amount and the first contact surface information;
a second evaluation step of evaluating a feel of the skin of the subject or a property of the agent based on the second feature amount and the second contact surface information;
A method for evaluating skin or an agent comprising the steps of: 9. The method for evaluating skin or an agent according to claim 8 , wherein the first contact surface information and the second contact surface information are vibration information generated on the contact surface. The method for evaluating skin or an agent according to claim 8 or 9 , wherein the first internal information and the second internal information are force information generated via the contact surface. The method for evaluating skin or an agent according to claim 10 , wherein the first internal information and the second internal information each include a plurality of types of force information. In the first calculation step, a first value is calculated by a first estimation process using the acquired internal first information;
The method for evaluating skin or an agent according to any one of claims 8 to 11 , characterized in that in the second calculation step, a second value is calculated by a second estimation process using the acquired second internal information. In the first estimation process, a first value is calculated using a first regression equation that is previously acquired by a regression analysis using the plurality of pieces of the internal first information acquired, the first regression equation having the internal first information as an explanatory variable and the first feature amount as a response variable;
The method for evaluating skin or an agent according to claim 12, characterized in that, in the second estimation process, the second value is calculated using a second regression equation that has been obtained in advance by regression analysis using a plurality of pieces of the internal second information obtained, the second regression equation having the internal second information as an explanatory variable and the second feature amount as a response variable . The method for evaluating skin or an agent according to claim 13 , wherein the first regression equation and the second regression equation are multiple regression equations obtained by multiple regression analysis using a plurality of types of force information. A contactor having flexibility that mimics the flexibility of a human finger;
a contact surface which is an outer surface of the contact and is brought into contact with a test object;
a force sensor that is provided inside the contact and measures a force received from the test object via the contact surface;
The contactor has a hollow structure and is attachable to and detachable from a human finger;
An acquisition means for acquiring a value measured by the force sensor;
A skin or agent evaluation system comprising an evaluation means for evaluating the subject or agent based on the value acquired by the acquisition means. A contactor having flexibility that mimics the flexibility of a human finger;
a contact surface which is an outer surface of the contact and is brought into contact with a test object;
a force sensor that is provided inside the contact and measures a force received from the test object via the contact surface;
The contacts include
a contact portion having the contact surface;
a core portion provided on the opposite side of the contact surface of the contact portion,
The force sensor is provided on the opposite side of the core portion to the contact portion,
An acquisition means for acquiring a value measured by the force sensor;
A skin or agent evaluation system comprising an evaluation means for evaluating the subject or agent based on the value acquired by the acquisition means.

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