Skin condition evaluation method

Abstract

To provide a technique for accurately evaluating a skin condition of a human hand through contact with an object.SOLUTION: A skin condition evaluation method includes the steps of: acquiring first contact information concerning a plurality of first contact objects by performing an evaluation object operation on each of a plurality of first contact objects by bringing a tested surface of a hand of a subject into contact with the plurality of first contact objects which have a common second physical property and different first physical properties in a plurality of physical properties which may affect a physical phenomenon generated in association with object contact; acquiring second contact information concerning a plurality of second contact objects by performing an evaluation object operation on each of the plurality of second contact objects by bringing the tested surface of the hand of the subject into contact with the plurality of second contact objects which have a common first physical property and different second physical properties; and evaluating a skin condition of the hand of the subject based on the first contact information and the second contact information.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a technique for evaluating the skin condition of a person's hands. [Background technology]

[0002] The following Patent Document 1 discloses a method for evaluating human skin or cosmetics, which evaluates the condition of a target surface, which is human skin or a surface created to resemble human skin, based on vibration information detected by a vibration sensor when a contactor is brought into contact with and slid over the target surface. The following Patent Document 2 discloses a skin or agent evaluation device that includes a flexible contactor that mimics the flexibility of a human finger, a contact surface on the outer surface of the contactor that comes into contact with a subject, and a force sensor that is provided inside the contactor and measures the force received from the subject via the contact surface. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-095263 [Patent Document 2] Japanese Patent Publication No. 2022-161710 Summary of the Invention [Problem to be solved by the invention]

[0004] The sensation of touch is generated when sensory receptors, such as mechanoreceptors, receive stimuli (vibration, friction, pressure, etc.) induced in the skin of the touching person's hand through mechanical interaction between the part that senses the touch and the part that is touched. The inventors believe that the skin acts as a mechanical filter when stimuli caused by touch are transmitted to mechanoreceptors, and that the way tactile sensations are perceived can differ depending on the skin condition of the person touching, and they discovered the importance of evaluating the skin condition of the person touching when evaluating tactile sensations. In view of this concept, the present invention provides a technology for evaluating the skin condition of a person's hands with high accuracy through contact with an object. [Means for solving the problem]

[0005] According to the present invention, there is provided a skin condition evaluation method using a measurement device capable of acquiring contact information between a contact object simulating human skin and a test surface of a subject's hand based on a detection signal from a sensor, the skin condition evaluation method including: a first acquisition step of acquiring first contact information about the test surface of the subject's hand by bringing the test surface of the subject's hand into contact with a plurality of first contact objects that have a common second physical property among a plurality of physical properties that can cause differences in physical phenomena occurring due to object contact and a first physical property that is different from the second physical property, and performing each of the actions to be evaluated; a second acquisition step of acquiring second contact information about the test surface of the subject's hand by bringing the test surface of the subject's hand into contact with a plurality of second contact objects that have the same first physical property but different from the second physical property, and performing each of the actions to be evaluated; and an evaluation step of evaluating the skin condition of the subject's hand based on the first contact information and the second contact information.

[0006] Furthermore, according to the present invention, there is provided an evaluation system that includes the sensor and the measuring device and is capable of executing the above-described skin condition evaluation method. Furthermore, the present invention provides a computer program that can cause a computer to execute the above-described skin condition evaluation method, or a computer-readable storage medium that stores such a computer program. [Effects of the Invention]

[0007] According to the above aspect, it is possible to provide a technology for evaluating the skin condition of a person's hand with high accuracy through contact with an object. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a flowchart showing a skin condition evaluation method according to the present embodiment (the present evaluation method). [Figure 2]10A and 10B are diagrams illustrating examples of contacts used for advance preparation. [Figure 3] 10 is a flowchart showing a skin condition evaluation method (second evaluation method) in a modified example. [Figure 4] FIG. 1 is a diagram conceptually illustrating an example of a hardware configuration of an evaluation system according to an embodiment of the present invention. [Figure 5] FIG. 5(a) is a table showing the characteristics of the six contacts used in this example, and FIG. 5(b) is a table showing the characteristics of the seven artificial skins used in this example. [Figure 6] This is a graph showing the coefficients of friction of simulated skin A, D, and E for each of six contacts (fingers 1 to 6). [Figure 7] This is a graph showing the coefficients of friction of simulated skin A, F, and G for each of the six contacts (fingers 1 to 6). [Figure 8] 10 is a graph showing the dispersion of the friction coefficients of the first and second simulated skin for each of six contacts (fingers 1 to 6) and a human finger. [Figure 9] This is a graph showing the coefficients of friction of simulated skin A, B, and C for each of the six contacts (fingers 1 to 6) and a human finger. [Figure 10] 1 is a graph plotting the average values and standard deviations of the friction coefficients of simulated skin A, B, and C calculated for each of six contacts (fingers 1 to 6) and a human finger on a two-axis coordinate system. DETAILED DESCRIPTION OF THE INVENTION

[0009] Preferred embodiments of the present invention will be described below. Note that the following embodiments are merely examples, and the present invention is not limited to the configurations of the following embodiments.

[0010] [Skin condition evaluation method] The skin condition evaluation method according to this embodiment (hereinafter referred to as the present evaluation method) evaluates the skin condition of a subject's hand. Here, the "subject's hand" may refer not only to the fingers but also to the palm and back of the hand. Furthermore, the skin condition to be evaluated may include the condition of the bare skin on the subject's hands, the condition of skin to which cosmetics have been applied (skin care has been performed using cosmetics, or skin care or makeup cosmetics have been applied), the condition of skin after cosmetic treatment, etc. Therefore, by evaluating the skin condition using this evaluation method, it is also possible to evaluate cosmetics and cosmetic treatments. The cosmetics to be evaluated are cosmetics that are applied to the skin of the subjects' hands, and examples include, but are not limited to, lotions, emulsions, creams, serums, packs, sheet lotions, skin care cosmetics, cleansing agents such as soap, cleansers, and makeup removers, foundations, makeup bases, liquid foundations, oil-based foundations, powder foundations, makeup cosmetics, sunscreen emulsions, sunscreen gels, sunscreen creams, and other UV protection cosmetics.

[0011] Examples of skin conditions that can be evaluated include the surface shape and physical properties of the skin, which can affect physical phenomena that occur when contacting an object. "Skin properties" are indices that represent the physical properties of skin. Examples of skin properties that can affect physical phenomena that occur when contacting an object include smoothness, adhesiveness, hardness (rigidity), etc., which are indices that represent the properties of skin against external forces. In this case, "smoothness" or "adhesiveness" can also be expressed as "surface properties." Furthermore, the surface shape of the skin, which can affect the physical phenomena that occur when the skin comes into contact with an object, includes, for example, the size of the surface irregularities, the surface roughness, and the like. The skin condition that can be evaluated can also be expressed as a skin condition related to tactile sensation or a skin condition that can cause a difference in tactile sensation. In this case, tactile sensations include, for example, frictional sensation, roughness, hardness, elasticity, stickiness, oiliness, moistness, refreshing sensation, dryness (dryness), stiffness, roughness, smoothness, softness, smoothness, firmness, sliminess, stickyness, silkiness, moisture, oiliness, adhesion, richness, skin compatibility, sticky sensation, bouncy sensation, penetration, and squeaky sensation. However, tactile sensation is not limited to these examples and may be an index of the sensation felt when touched. Physical phenomena that occur when objects come into contact include, for example, friction, repulsion, deformation, adhesion, vibration, etc. that occur on the contact surface between objects (for example, between the contacted object and the subject's hand).

[0012] This evaluation method is carried out using a measurement device that can acquire contact information between the test surface of the subject's hand and the contacted object based on detection signals from a sensor. The sensor and measurement device will be described in detail later. The contacted object used in this evaluation method is not limited in any way to its material or structure, as long as it has a specified surface shape and physical properties and is configured so that contact information can be obtained by the measurement device when the object is in contact with the test surface of the subject's hand and performs the action to be evaluated. However, when the skin condition related to the feel of bare skin and skin that has been treated with cosmetics or cosmetic treatments is to be evaluated, it is preferable to use simulated skin having physical properties and a surface shape that mimic human skin as the contacted object. In the examples described below, simulated skin is used as the contacted object. Contact information is measurement information acquired by a measurement device when a subject performs a motion to be evaluated by bringing the test surface of the subject's hand into contact with a contacted object. It can also be described as characteristic information of physical quantities occurring in the motion to be evaluated on the contact surface of the test object that comes into contact with the test surface of the subject's hand. Contact information can be acquired based on detection signals output from sensors such as force sensors and vibration sensors, or based on information detected by other sensors. For example, the contact information can be acquired from sound generated by contact or video information capturing the vibration of the test surface of the hand or the contacted object. Furthermore, information derived from friction or intensity values obtained from the acquired vibration waveform can also be acquired as contact information. Furthermore, information on the movement of the hand or contactor at the time of contact (e.g., velocity, acceleration, angular velocity, and posture information such as the tilt of the contactor) acquired by a motion sensor or video information can also be acquired as contact information. Examples of such contact information include friction information and vibration information. The motion to be evaluated will be described later.

[0013] FIG. 1 is a flowchart showing the skin condition evaluation method according to this embodiment (hereinafter referred to as the present evaluation method). As shown in Figure 1, this evaluation method includes a step (S11) of acquiring first contact information by bringing the test surface of the subject's hand into contact with a plurality of first contactable objects and performing each of the actions to be evaluated, a step (S12) of acquiring second contact information by bringing the test surface of the subject's hand into contact with a plurality of second contactable objects and performing each of the actions to be evaluated, and a step (S13) of evaluating the skin condition of the subject's hand based on the first contact information and second contact information acquired in steps (S11) and (S12).

[0014] As described above, the inventors have found that the perception of tactile sensation is greatly influenced by the skin condition of the person's hand that makes the touch. As will be described later as an example, the inventors conducted experiments using, instead of a human hand, a plurality of contactors that mimic the flexibility of human fingers and have different physical properties or surface shapes, or both, that can affect physical phenomena that occur when an object is touched. This led to the discovery of new patterns of physical properties and surface shapes of contactors in which the contact sensitivity to a first physical property of a contacted object and the contact sensitivity to a second physical property of the contacted object are mutually reversed, and the inventors came up with the new idea that the skin condition of a human hand can be evaluated using such patterns of physical properties and surface shapes. Here, "touch sensitivity to the physical properties of the contactor" refers to the degree of change in the contact information between contacted objects obtained by using a certain contactor to perform an action to be evaluated on each contacted object, each of which has different physical properties.If the degree of change in the contact information between contacted objects is large, the contact sensitivity can be expressed as high, and if the degree of change is small, the contact sensitivity can be expressed as low.

[0015] Therefore, among multiple physical properties that can affect the physical phenomenon that occurs when an object is touched on the touched side, the following contacted objects were prepared, focusing on first and second physical properties (mutually different physical properties) whose contact sensitivity is reversed depending on the physical properties and surface shape pattern of the touching side. That is, multiple contacted objects (referred to as first contacted objects) having different first physical properties but a common second physical property were used in step (S11), and multiple contacted objects (referred to as second contacted objects) having different second physical properties but a common first physical property were used in step (S12). For example, the first and second physical properties are surface texture and hardness. However, the first and second physical properties are not limited to the combination of surface texture and hardness.

[0016] The first contact information acquired in step (S11) and the second contact information acquired in step (S12) are groups of contact information acquired by a measuring device for each first contacted object or each second contacted object in association with the action to be evaluated. For example, if the sensor that sends the detection signal to the measurement device is a multi-axis sensor, the first contact information and the second contact information can be obtained as a friction coefficient (Fx / Fz) that can be calculated from a horizontal force (Fx) and a vertical force (Fz) with respect to the contact surface, or data calculated by some method from one or both of Fx and Fz. In this case, the first contact information and the second contact information can also be referred to as first friction information and second friction information. However, the friction information may be contact information corresponding to the friction force that occurs when the target movement to be evaluated is performed with the test surface of the hand in contact with the contacted object, and the method of acquiring the friction information and its specific content are not limited to the examples described above. Furthermore, if the sensor is a vibration sensor, vibration intensity and vibration waveform data can be acquired as the first contact information and the second contact information. Furthermore, vibration power spectrum data obtained by performing processing such as frequency analysis on such vibration waveform data, or feature data extracted from such vibration-related data, may be acquired as the first contact information and the second contact information. In this case, the first contact information and the second contact information can be referred to as first vibration information and the second vibration information. However, the vibration information may be contact information related to vibrations that occur when the action to be evaluated is performed with the test surface of the hand in contact with the contacted object, and the acquisition method and specific content thereof are not limited to the above-mentioned examples. However, the acquired first contact information and second contact information are not limited to this example.

[0017] Furthermore, the action to be evaluated for obtaining the first contact information and the second contact information may be any action that can generate frictional force, repulsive force, vibration, etc. on the contact surface, such as sliding, twisting, tapping, etc. The sensor may have any configuration that can detect contact information associated with the motion to be evaluated, and the specific configuration is not limited thereto. Furthermore, the sensor may be installed at any position that can detect contact information associated with the motion to be evaluated. For example, the sensor may be installed under the first contacted object and the second contacted object.

[0018] In step (S13), the skin condition of the subject's hand is evaluated using at least the first contact information and second contact information thus acquired. Here, the first contact information is measurement information for each first contacted object that has a different first physical property but a common second physical property, and therefore indicates contact sensitivity to the first physical property, and the second contact information is measurement information for each second contacted object that has a different second physical property but a common first physical property, and therefore indicates contact sensitivity to the second physical property. Therefore, by using the first contact information and the second contact information, it is possible to determine the relationship between the contact sensitivity to the first physical property and the contact sensitivity to the second physical property, thereby evaluating the skin condition of the subject's hand. For example, if the first contact information and the second contact information indicate that the contact sensitivity to the first physical property and the contact sensitivity to the second physical property are mutually reversed, it can be estimated that the skin condition of the subject's hand has a specific physical property pattern that may cause such a reversal phenomenon.

[0019] Here, the contact sensitivity for the first physical property corresponds to the degree of variation in the first contact information between the first contacted objects, and the contact sensitivity for the second physical property corresponds to the degree of variation in the second contact information between the second contacted objects. Therefore, in step (S13), the skin condition of the subject's hand can be evaluated by using at least the degree of variation in the first contact information between the first contacted objects and the degree of variation in the second contact information between the second contacted objects. For example, the degree of variation in the first contact information and the second contact information can be calculated using variance, standard deviation, etc.

[0020] The following examples are given as examples of evaluation methods in step (S13). For example, it is possible to obtain contact information for each contactor in advance by performing the action to be evaluated on the plurality of first contacted objects and the plurality of second contacted objects using the plurality of contactors as described above, retain evaluation information on the contact surface state of each contactor based on this contact information, and further use this evaluation information to perform evaluation.

[0021] The contacts used in such advance preparation will be described with reference to the example shown in FIG. Figure 2 shows an example of a contactor used for advance preparation. Figure 2(a) shows the appearance of the contactor 100 when worn on a human finger, and Figure 2(b) shows a schematic cross section of the contactor 100 when worn on a human finger. 2 has a shape that can be worn on a human finger, and is formed to have flexibility that mimics the flexibility of a human finger. Mimicking the flexibility of a human finger means having flexibility that is close to the characteristics of a human finger, such as softness and hardness, and this is achieved by forming the contact 100 from an elastomer such as soft rubber or gel.

[0022] 2 has a laminated structure in which an upper layer 10, an intermediate layer 20, and a lower layer 30 are laminated. The upper layer 10 includes a contact surface that comes into contact with the contacted object, the intermediate layer 20 is provided on the opposite side of the contact surface of the upper layer 10, and the lower layer 30 is provided more inward than the intermediate layer 20. However, the contact 100 is not limited to the laminated structure shown in the example of FIG. 1, and may have a two-layer structure or a structure of four or more layers, or may have a single-layer structure as long as it includes a contact surface that comes into contact with the contacted object. For example, in order to make the softness, hardness, and other properties closer to those of a human finger, the upper layer 10 is made of silicone, and the middle layer 20 is made of urethane gel. The lower layer 30 is made of ASA resin. However, the materials of each layer of the contact 100 are not limited to this example, and the upper layer 10 and the middle layer 20 may be made of the same material, for example, urethane gel. Furthermore, in order to achieve various softnesses or hardnesses, multiple upper layer 10 and multiple middle layer 20 with different flexibilities may be configured to be detachable from the lower layer 30. The contact surface of the upper layer 10 has a surface shape that mimics the surface shape of a human finger. For example, grooves that mimic fingerprints are formed on the contact surface of the upper layer 10. However, the grooves may have any shape other than elliptical, such as spiral or linear. Furthermore, the contact surface may have a flat surface shape without grooves, depending on the test surface of the hand to be evaluated.

[0023] 2, the force sensor 40 and the vibration sensor 50 are provided on the contactor 100. The force sensor 40 is provided inside the lower layer 30 of the contactor 100, and the vibration sensor 50 is provided by wrapping around the contactor 100. However, the arrangement of the force sensor 40 and the vibration sensor 50 is not limited to the example in FIG. 2. The force sensor 40 may be installed under the contacted object, as in this evaluation method. The force sensor 40 is, for example, a multi-axis sensor. However, the force sensor 40 is not limited to this example and may be a sensor using a strain gauge, capacitance, pressure-sensitive conductivity, piezoelectric effect, piezoresistive effect, light, acoustics, a magnetic field, contact resistance, or the like. The vibration sensor 50 is not limited to a specific configuration as long as it can measure vibrations occurring on the contact surface. The vibration sensor 50 can be realized by, for example, a piezoelectric element, a strain gauge, an acceleration sensor, or the like.

[0024] The contactor 100 in the example of Fig. 2 has the same configuration as the contactor disclosed in the above-mentioned Patent Document 2. However, the contactor to be used is not limited to the example of Fig. 2. The contactor to be used only needs to have flexibility that mimics the flexibility of a human finger, and there are no limitations on its structure or material.

[0025] With this structure, a plurality of contacts are prepared, each having specified physical properties or surface shapes, or both, that can affect physical phenomena that occur when an object comes into contact with the contact, and contact information for each contact is acquired in the same manner as in steps (S11) and (S12) of this evaluation method. Then, evaluation information for the contact surface state of each contact based on the acquired contact information is acquired in advance. An example of the evaluation information acquired in advance is rule information that classifies each contactor by its physical properties and surface shape based on the tendency between the contact information acquired for the first contacted object and the contact information acquired for the second contacted object. Specifically, rule information can be set that classifies the contact surface state of each contactor by its surface shape and physical properties based on the magnitude relationship between the degree of variation in the contact information acquired for the first contacted object and the degree of variation in the contact information acquired for the second contacted object. However, the evaluation information acquired in advance is not limited to this example. For example, a function that uses the statistics of the contact information acquired for the first contacted object and the statistics of the contact information acquired for the second contacted object as parameters and outputs an index value indicating the contact surface state of each contact piece or an identifier of the contact surface state group to which each contact piece belongs may be stored in advance as the evaluation information.

[0026] When evaluation information is acquired in advance in this manner, in step (S13), the skin condition of the subject's hand can be classified using the pre-stored evaluation information in addition to the first contact information and second contact information. As another example, in step (S13), in addition to the first contact information and the second contact information, pre-stored evaluation information may be further used to identify the contact that corresponds to the skin condition of the subject's hand from among the multiple contacts. In this case, correspondence information linking the tendencies of the contact information acquired about the first contacted object and the contact information acquired about the second contacted object with the identifiers of each contactor is stored in advance as the evaluation information, and the identifiers of contactors linked with the tendencies of contact information similar to the tendencies of the first contact information and second contact information of the subject acquired in steps (S11) and (S12) are selected based on this evaluation information, thereby making it possible to identify the contactors. In other words, "contactors corresponding to the skin condition of the subject's hand" means contactors with a contact surface condition that is the same as or similar to the skin condition of the subject's hand.

[0027] By using the contactor identified in this way, it becomes possible to obtain tactile information that is estimated to be felt by the subject through touch, without actually using the subject's hand. For example, by acquiring and analyzing measurement information (e.g., friction information, vibration information, etc.) obtained by bringing the contactor into contact with the test surface of an object and sliding it, it becomes possible to estimate the tactile sensation that the subject will experience from the test surface.

[0028] Furthermore, by linking the subject's preferred tactile sensation with the measurement information (e.g., friction information, vibration information, etc.) that produces that tactile sensation, it is possible to identify cosmetics and beauty procedures that have the subject's preferred tactile sensation. For example, if the measurement information obtained by touching and sliding a contactor corresponding to the subject's hand over an object (e.g., simulated skin) to which cosmetics have been applied corresponds to the subject's preferred tactile sensation, it can be predicted that the subject will prefer the tactile sensation of that cosmetic. Therefore, information about that cosmetic can be output as recommended product information for the subject. In this case, in step (S13), in addition to the first contact information and the second contact information, pre-stored evaluation information may also be used to output information on cosmetics or cosmetic procedures according to the subject's sense of touch.

[0029] [Variations] The contents of the above-described embodiment can be modified as appropriate. For example, although the above-described embodiment does not specifically mention the surface shape of the contacted object, the inventors have discovered that, as will be described later as an example, the surface shape of the touched side can be classified with high accuracy by using contact information as measurement information. Therefore, the above-described present evaluation method may further use contacted objects with different surface shapes.

[0030] FIG. 3 is a flowchart showing a modified skin condition evaluation method (hereinafter referred to as the second evaluation method). As shown in Figure 3, the second evaluation method includes a step (S31) of acquiring first contact information by contacting the test surface of the subject's hand with a plurality of first contactable objects and performing each of the actions to be evaluated, a step (S32) of acquiring second contact information by contacting the test surface of the subject's hand with a plurality of second contactable objects and performing each of the actions to be evaluated, a step (S33) of acquiring third contact information by contacting the test surface of the subject's hand with a plurality of third contactable objects and performing each of the actions to be evaluated, and a step (S34) of evaluating the skin condition of the subject's hand based on the first contact information, second contact information, and third contact information acquired in steps (S31), (S32), and (S33).

[0031] The plurality of first contacted objects used in step (S31) are different from one another in the first physical property but have a common second physical property and surface shape; the plurality of second contacted objects used in step (S32) are different from one another in the second physical property but have a common first physical property and surface shape; and the plurality of third contacted objects used in step (S33) are different from one another in the surface shape but have a common first physical property and second physical property. The methods for acquiring the first contact information, the second contact information, and the third contact information in steps (S31), (S32), and (S33) are the same as steps (S11) and (S12) in the above-described embodiment.

[0032] In step (S34), in addition to the first contact information and the second contact information, the skin condition of the subject's hand is evaluated using third contact information obtained using a third contacted object having a different surface shape. Just as the first contact information indicates the contact sensitivity to the first physical property and the second contact information indicates the contact sensitivity to the second physical property, the third contact information indicates the contact sensitivity to the surface shape, and the contact sensitivity to the surface shape corresponds to the degree of variation among the third contacted objects in the third contact information. Therefore, by using the third contact information in addition to the first contact information and the second contact information, it is possible to evaluate the skin condition of the subject's hand based on the relationship between the contact sensitivity to the first physical property, the contact sensitivity to the second physical property, and the contact sensitivity to the surface shape. Also, in step (S34), it is possible to evaluate the skin condition of the subject's hand by using at least the degree of variation between first contacted objects in the first contact information, the degree of variation between second contacted objects in the second contact information, and the degree of variation between third contacted objects in the third contact information.

[0033] Furthermore, in the evaluation in step (S34), evaluation information previously acquired using the contactors may be further used, as described in the above embodiment. That is, the evaluation target action is performed in advance on the plurality of first contacted objects, the plurality of second contacted objects, and the plurality of third contacted objects using the plurality of contactors described above to acquire contact information for each contactor, and evaluation information on the contact surface state of each contactor based on this contact information is stored, and this evaluation information is further used to perform the evaluation. Examples of the evaluation information acquired in advance include statistics (average value, variance, standard deviation, etc.) of contact information acquired about the third contacted object and rule information for classifying each contactor by its physical properties and surface shape. Furthermore, information linking the statistics of contact information acquired about the third contacted object with the physical properties and surface shape of each contactor may be used as the evaluation information. If such evaluation information has been obtained in advance, for example, as in the above-described embodiment, the skin condition of the subject's hand may be classified using the first contact information and second contact information and evaluation information obtained in steps (S31) and (S32), and then the skin condition of the subject's hand may be further classified using the third contact information and evaluation information obtained in step (S33), and the results of both classifications may be integrated, or the skin condition of the subject's hand may be classified using all of the first contact information, second contact information, and third contact information and the evaluation information.

[0034] In this way, as in the above-described embodiment, in step (S34), the first contact information, second contact information, third contact information, and pre-stored evaluation information can be used to identify the contact from among the multiple contacts that corresponds to the skin condition of the subject's hand, and information on cosmetics or beauty procedures that corresponds to the subject's sense of touch can also be output.

[0035] [Rating System] The evaluation methods according to the above-described embodiments and modifications can be executed by an evaluation system 1 as shown in Fig. 4. Fig. 4 is a diagram conceptually showing an example of the hardware configuration of the evaluation system 1 in this embodiment. The evaluation system 1 comprises at least a sensor 9 and an evaluation device 2 .

[0036] The evaluation device 2 is a so-called computer, and includes a CPU (Central Processing Unit) 3, a memory 4, an input / output interface (I / F) 5, a communication unit 6, etc. The memory 4 is a RAM (Random Access Memory), a ROM (Read Only Memory), a hard disk, a portable storage medium, etc. The communication unit 6 communicates with other computers via a communication network and exchanges signals with other devices such as the sensor 9. A portable recording medium or the like can also be connected to the communication unit 6.

[0037] The input / output I / F 5 can be connected to an output device 7, an input device 8, etc. The output device 7 is a display device such as an LCD (Liquid Crystal Display) or a CRT (Cathode Ray Tube) display, a printer, etc. The input device 8 is a device that accepts input of user operations such as a keyboard, a mouse, etc. However, the output device 7 and the input device 8 may be an integrated touch panel.

[0038] The evaluation device 2 may include hardware elements not shown in FIG. 4, and the hardware configuration of the evaluation device 2 is not limited to the example of FIG. In addition, in the example of Figure 4, for ease of explanation, a configuration is shown in which a sensor 9 capable of outputting a detection signal that is the source of contact information, such as a force sensor, is connected to the communication unit 6, but the sensor 9 may also be connected to the input / output I / F 5.

[0039] The evaluation system 1 executes the evaluation method according to the above-described embodiment or modification by, for example, reading and executing a computer program stored in the memory 4 by the CPU 3. Therefore, it can be said that the CPU 3 or the evaluation device 2 (computer) executes each step illustrated in FIGS. For example, the CPU 3 executes step (S11) and step (S12) to acquire first contact information and second contact information based on the detection signal sent from the sensor 9. The CPU 3 also executes step (S13) to evaluate skin information of the subject's hand and can generate evaluation information indicating the evaluation result. Similarly, the CPU 3 executes steps (S31), (S32), and (S33) to acquire first contact information, second contact information, and third contact information based on the detection signal sent from the sensor 9. The CPU 3 executes step (S34) to evaluate the skin information of the subject's hand and can generate evaluation information indicating the evaluation result. The CPU 3 can also output evaluation information indicating the results of the evaluation performed in step (S13) or step (S34) to the output device 7. The evaluation information may be displayed on the display device or printed out by a printer.

[0040] The computer program may be stored in memory 4 in advance, or may be installed from a portable recording medium such as a CD (Compact Disc) or memory card, or from another computer on the network via input / output I / F 5 or communication unit 6, and then stored in memory 4.

[0041] Some or all of the above content can also be specified as follows: However, the above-described embodiments and modifications are not limited to the following description.

[0042] <1> A skin condition evaluation method using a measurement device capable of acquiring contact information between a test surface of a test subject's hand and a contacted object based on a detection signal from a sensor, comprising: a first acquisition step of acquiring first contact information related to a plurality of first contacted objects by bringing the test surface of the subject's hand into contact with a plurality of first contacted objects each having a common second physical property among a plurality of physical properties that can affect a physical phenomenon occurring due to object contact and a different first physical property that is different from the second physical property, and performing an evaluation target action on each of the first contacted objects; a second acquiring step of acquiring second contact information about a plurality of second contacted objects by bringing the test surface of the subject's hand into contact with the plurality of second contacted objects that have the same first physical property but different second physical properties, and performing an evaluation target action on each of the plurality of second contacted objects; an evaluation step of evaluating a skin condition of the subject's hand based on the first contact information and the second contact information; A method for evaluating skin condition comprising:

[0043] <2> In the evaluation step, a skin condition of the subject's hand is evaluated using at least a degree of variation between first contacted objects in the first contact information and a degree of variation between second contacted objects in the second contact information. <1> The method for evaluating skin condition described in 1. <3> One of the first physical property and the second physical property is surface texture or hardness, or the first physical property and the second physical property are surface texture and hardness. <1> or <2> The method for evaluating skin condition described in 1. <4> A plurality of contactors that mimic the flexibility of human fingers and have different physical properties or surface shapes, or both, that can affect physical phenomena that occur when an object is contacted, are used to perform the evaluation target operation on the plurality of first contacted objects and the plurality of second contacted objects, and evaluation information on the contact surface state of each contactor is obtained in advance based on contact information of each contactor; In the evaluation step, the previously acquired evaluation information is further used to classify the skin condition of the subject's hand. <1> from <3> 10. The method for evaluating a skin condition according to claim 9, wherein the skin condition is evaluated by the method according to any one of the above items. <5> A plurality of contactors that mimic the flexibility of human fingers and have different physical properties or surface shapes, or both, that can affect physical phenomena that occur when an object is contacted, are used to perform the evaluation target operation on the plurality of first contacted objects and the plurality of second contacted objects, and evaluation information on the contact surface state of each contactor is obtained in advance based on contact information of each contactor; In the evaluation step, a contact corresponding to the skin condition of the subject's hand is identified from the plurality of contacts by further using the evaluation information acquired in advance. <1> from <3> 10. The method for evaluating a skin condition according to claim 9, wherein the skin condition is evaluated by the method according to any one of the above items. <6> A plurality of contactors that mimic the flexibility of human fingers and have different physical properties or surface shapes, or both, that can affect physical phenomena that occur when an object is contacted, are used to perform the evaluation target operation on the plurality of first contacted objects and the plurality of second contacted objects, and evaluation information on the contact surface state of each contactor is obtained in advance based on contact information of each contactor; In the evaluation step, the previously acquired evaluation information is further used to output information about the cosmetic product or the cosmetic procedure according to the subject's sense of touch. <1> from <3> 10. The method for evaluating a skin condition according to claim 9, wherein the skin condition is evaluated by the method according to any one of the above items. <7> a third acquiring step of acquiring third contact information regarding a plurality of third contactable objects by bringing the test surface of the subject's hand into contact with the plurality of third contactable objects having the same first physical property and the second physical property but different surface shapes, and performing an evaluation target action on each of the third contactable objects; Further comprising: the plurality of first contacted objects have a common surface shape, the plurality of second contacted objects have a common surface shape, In the evaluation step, a skin condition of the subject's hand is evaluated based on the first contact information, the second contact information, and the third contact information. <1> from <3> 10. The method for evaluating a skin condition according to claim 9, wherein the skin condition is evaluated by the method according to any one of the above items. <8> A plurality of contactors that mimic the flexibility of human fingers and have different physical properties or surface shapes, or both, that can affect physical phenomena that occur when an object is contacted are used to perform the evaluation target operation on the plurality of first contacted objects, the plurality of second contacted objects, and the plurality of third contacted objects, and evaluation information on the contact surface state of each contactor is obtained in advance based on the contact information of each contactor; In the evaluation step, the previously acquired evaluation information is further used to classify the skin condition of the subject's hand. <7> The method for evaluating skin condition described in 1. <9> A plurality of contactors, each simulating the flexibility of a human finger and each having different physical properties that can affect a physical phenomenon that occurs when an object is contacted, are used to perform the evaluation target operation on the plurality of first contacted objects, the plurality of second contacted objects, and the plurality of third contacted objects, and evaluation information on the contact surface state of each contactor is obtained in advance based on contact information of each contactor; In the evaluation step, a contact corresponding to the skin condition of the subject's hand is identified from the plurality of contacts by further using the evaluation information acquired in advance. <7> The method for evaluating skin condition described in 1. <10> A plurality of contactors, each simulating the flexibility of a human finger and each having different physical properties that can affect a physical phenomenon that occurs when an object is contacted, are used to perform the evaluation target operation on the plurality of first contacted objects, the plurality of second contacted objects, and the plurality of third contacted objects, and evaluation information on the contact surface state of each contactor is obtained in advance based on contact information of each contactor; In the evaluation step, the previously acquired evaluation information is further used to output information about the cosmetic product or the cosmetic procedure according to the subject's sense of touch. <7> The method for evaluating skin condition described in 1. <11> the sensor and the measuring device, <1> from <10> An evaluation system capable of executing the skin condition evaluation method described in any one of the above.

[0044] The above content will be explained in more detail below with reference to examples, but the following examples do not limit the above content in any way. [Example]

[0045] A specific example of acquiring evaluation information on the contact surface state of multiple contactors will be described. In this example, simulated skin that resembles human skin is used as the contacted object, and friction information is used as the contact information. That is, by using multiple contactors to perform an evaluation target action on multiple first simulated skins (corresponding to first contacted objects) and multiple second simulated skins (corresponding to second contacted objects), friction information (corresponding to contact information) for each contactor is acquired, and evaluation information on the contact surface state of each contactor is acquired based on this friction information. Note that in the following description, the contact surface state of the contactors may also be referred to as the skin state of the contactors.

[0046] FIG. 5(a) shows the characteristics of the six contacts used in this example, and FIG. 5(b) shows the characteristics of the seven artificial skins used in this example. As shown in Figures 5(a) and 5(b), the six contacts used in this embodiment differ in one or more of the size of surface irregularities, surface texture, or hardness, and the seven artificial skins differ in one or more of the surface roughness, surface texture, or hardness. Hereinafter, the contacts indicated as "Finger 1" to "Finger 6" in FIG. 5(a) will be referred to as contacts 1 to 6, and the simulated skins indicated as "Simulated Skin A" to "Simulated Skin G" in FIG. 5(b) will be referred to simply as Simulated Skin A to Simulated Skin G.

[0047] The contactor used in this embodiment has the same structure as the contactor 100 shown in Fig. 2, with the upper layer 10 and middle layer 20 made of urethane, and the lower layer 30 made of ASA resin. This three-layer structure achieves the surface shape and physical properties of each contactor shown in Fig. 5(a). Note that this embodiment differs from the example in Fig. 2 in that the force sensor 40 is placed under the artificial skin.

[0048] Specifically, the contact surface (upper layer 10) of each contactor that comes into contact with the contacted object has an uneven shape that imitates a fingerprint, and the cross section of the convex parts of the uneven shape is trapezoidal. The upper base of the trapezoid is set to 0.3 mm, the lower base is set to 0.5 mm, and the height is changed as shown by the size of the surface unevenness in Figure 5(a). The contact surface of each contactor is coated with a different type of slipperiness, resulting in the different surface textures (dry or standard) shown in Figure 5(a). The surface texture labeled "dry" is slippery (friction coefficient 0.6), while the surface texture labeled "standard" is medium slipperiness (friction coefficient 0.8). The hardness of each contact is varied by changing the Young's modulus of the three layers: upper layer 10, middle layer 20, and lower layer 30. In Fig. 5(a), the hardness (softer) of a contact with a three-layer Young's modulus of 0.03 MPa is indicated as "30," and the hardness (harder) of a contact with a three-layer Young's modulus of 0.06 MPa is indicated as "40."

[0049] Regarding the surface roughness of each simulated skin in Figure 5(b), the arithmetic mean roughness (Ra) of 20.1 μm is labeled as "fine," the Ra of 23.7 μm is labeled as "medium," and the Ra of 29.4 μm is labeled as "coarse." The variations in the surface texture of each simulated skin were achieved by coating treatments with different slipperiness. In Figure 5(b), the surface texture labeled "Dry" is slippery (friction coefficient 0.5), the surface texture labeled "Standard" is medium slipperiness (friction coefficient 0.7), and the surface texture labeled "Moist" is not slippery (friction coefficient 1.1). Regarding the hardness of each simulated skin, those with a Young's modulus of 0.03 MPa are labeled "small" in Figure 5(b), those with a Young's modulus of 0.07 MPa are labeled "medium" in Figure 5(b), and those with a Young's modulus of 0.14 MPa are labeled "large" in Figure 5(b).

[0050] In this embodiment, friction information is acquired as contact information based on a detection signal sent from the force sensor 40 as the contactor is brought into contact with and slid over the artificial skin, which is the contacted object. The contact was slid over a width of 5 cm at a speed of 10 cm / sec with a pressing force of 0.4 N. As friction information, the friction coefficient (Fx / Fz) was calculated from the shear force (Fx) and shear force (Fz) based on the detection signal from the force sensor 40. Then, the average value of the five friction coefficients obtained from the five measurements was calculated.

[0051] FIG. 6 is a graph showing the friction coefficients of simulated skin A, D, and E for each of the six contacts (fingers 1 to 6), FIG. 7 is a graph showing the friction coefficients of simulated skin A, F, and G for each of the six contacts (fingers 1 to 6), and FIG. 8 is a graph showing the variance of the friction coefficients of the first and second simulated skin for each of the six contacts (fingers 1 to 6) and the human finger. The skin mimics A, D, and E shown in Figure 6 have the same surface roughness and hardness, but different surface textures. The skin mimics A, F, and G shown in Figure 7 have the same surface roughness and hardness, but different hardness. Therefore, simulated skins A, D, and E correspond to multiple first simulated skins that have a common surface shape (surface roughness) and second physical property (hardness) but different first physical properties (surface characteristics), and simulated skins A, F, and G correspond to multiple second simulated skins that have a common surface shape (surface roughness) and first physical property (surface characteristics) but different second physical properties (hardness).

[0052] According to Fig. 6, the more non-slip the surface texture of contacts 1, 5, and 6, the larger the friction coefficient, and differences appear in the friction coefficient for each simulated skin. Furthermore, when the variance of the friction coefficient for each contact was calculated as shown in Fig. 8, the variances for contacts 1, 5, and 6 were 0.1 or more, while the variances for the other contacts were less than 0.1. In other words, the degree of variance in the first friction coefficient for contacts 1, 5, and 6 was large, while the degree of variance in the first friction coefficient for contacts 2, 3, and 4 was small. 7, the greater the hardness of contacts 2, 3, and 4, the smaller the friction coefficient, revealing differences in the friction coefficient for each simulated skin. Furthermore, as shown in Fig. 8, when the variance of the friction coefficient for each contact was calculated, the variance for contacts 2, 3, and 4 was greater than 0.05, while the variance for the other contacts was less than 0.03. In other words, the degree of variation in the second friction coefficient for contacts 2, 3, and 4 was large, while the degree of variation in the second friction coefficient for contacts 1, 5, and 6 was small.

[0053] As a result, for contacts 1, 5, and 6, the degree of variation in friction coefficient with respect to differences in skin surface texture is greater than the degree of variation in friction coefficient with respect to differences in skin hardness (showing a downward trend in the graph of FIG. 8), and for contacts 2, 3, and 4, the degree of variation in friction coefficient with respect to differences in skin surface texture is smaller than the degree of variation in friction coefficient with respect to differences in skin hardness (showing an upward trend in the graph of FIG. 8). In other words, it can be said that contacts 1, 5, and 6 have physical properties and surface shapes that make them highly sensitive to skin surface texture and less sensitive to skin hardness, and contacts 2, 3, and 4 have physical properties and surface shapes that make them highly sensitive to skin hardness and less sensitive to skin surface texture.

[0054] As described above, according to the friction information obtained using the plurality of first simulated skins and the plurality of second simulated skins, the plurality of contacts 1 to 6 can be classified into contacts 1, 5, and 6 (hereinafter sometimes referred to as the first type) that have physical properties and surface shapes that make them more sensitive to the surface texture of the skin than to the hardness of the skin, and contacts 2, 3, and 4 (hereinafter sometimes referred to as the second type) that have physical properties and surface shapes that make them more sensitive to the hardness of the skin than to the surface texture of the skin. The first type of contacts 1, 5 and 6 have large surface irregularities (0.2 mm or more) and have a surface texture that is easy to slip on, while the second type of contacts 2, 3 and 4 have small surface irregularities (0.06 mm and 0.1 mm) or have a surface texture that is difficult to slip on. According to this embodiment, such classification rules based on the friction information of the contacts can be acquired in advance as evaluation information on the skin condition of each contact.

[0055] Fig. 8 shows the variance values of the first friction information and the second friction information for a subject's finger (denoted as "human finger") obtained in the same manner as the contacts. As shown in Fig. 8, the variance values of the first friction information and the second friction information for this subject's finger show an upward trend. Therefore, the skin condition of the subject's fingers can be evaluated as belonging to the same second type as contacts 2, 3, and 4, with small surface irregularities or a non-slip surface. If cosmetics have been applied to the subject's fingers, the cosmetics can be evaluated as having a high level of moisturizing or high softness, corresponding to the second type. If the skin is determined to belong to the first type, the cosmetics can be evaluated as having a low level of moisturizing or low softness, corresponding to the first type. In this way, in this example, it was demonstrated that it is possible to evaluate the skin condition of the subject's hand based on the evaluation information acquired using a plurality of contacts as described above.

[0056] Furthermore, in this embodiment, in addition to the first contact information and second contact information as described above, a specific example is shown in which third contact information regarding multiple third contacted objects that have the same first and second physical properties but different surface shapes is further used to evaluate the skin condition of the subject's hands. Here, artificial skin was used as the contact object. Specifically, artificial skin A, B, and C shown in Figure 5(b) were used as multiple third artificial skins. The artificial skins A, B, and C have the same surface texture and hardness, but each has a different surface shape (surface roughness). Then, as each contactor was brought into contact with each third artificial skin and slid, friction information was acquired as contact information based on the detection signal sent from the force sensor 40. The contact was slid over a width of 5 cm at a speed of 10 cm / sec with a pressing force of 0.4 N. As friction information, the friction coefficient (Fx / Fz) was calculated from the shear force (Fx) and shear force (Fz) based on the detection signal from the force sensor 40. Then, the average value of the five friction coefficients obtained from the five measurements was calculated.

[0057] FIG. 9 is a graph showing the coefficients of friction of simulated skin A, B, and C for each of the six contacts (fingers 1 to 6) and a human finger. 9, for all contacts, the coefficient of friction increases as the surface roughness increases, and differences appear in the coefficient of friction for each simulated skin. Similar to these contacts, for the human finger, the coefficient of friction increases as the surface roughness increases, and differences appear in the coefficient of friction for each simulated skin. Therefore, it can be said that differences in the surface shape of the simulated skin are reflected in the degree of change in the friction coefficient, demonstrating the effectiveness of further using a third friction coefficient obtained using a third simulated skin with a different surface shape when evaluating the skin condition of the contactor and the human hand, which are the touching sides.

[0058] FIG. 10 is a graph plotting the average values and standard deviations of the friction coefficients of simulated skin A, B, and C calculated for each of the six contacts (fingers 1 to 6) and the human finger on a two-axis coordinate system. According to FIG. 10, since the markers indicating the subject's fingers are close to the markers indicating contacts 2, 3, and 4, it can be seen that the skin condition of the subject's fingers can be classified into the second type of contacts 2, 3, and 4, similar to the classification based on the first friction information and second friction information described above. Furthermore, since the marker representing the subject's fingers shows a high similarity to contacts 2 and 4 of the second type, the skin condition of the subject's fingers can be evaluated as having a surface irregularity of approximately 0.1 to 0.2 mm, a moist surface texture, and being soft.

[0059] In this way, by using multiple contactors to perform the evaluation target action on multiple third simulated skins and obtaining evaluation information on the skin condition of each contactor based on the friction information of each contactor in advance, it was demonstrated that it is possible to evaluate the skin condition of the subject's hand based on the third friction information and the evaluation information in addition to the first friction information and second friction information.

[0060] In the flowcharts used in the above description, multiple steps (processes) are described in order, but the order of execution of the steps performed in each embodiment is not limited to the order described. In each embodiment, the order of the steps shown in the drawings can be changed to the extent that the content is not affected. Furthermore, the above-described embodiments can be combined to the extent that the content is not contradictory. [Explanation of symbols]

[0061] 1. Rating System 2 Evaluation equipment 3 CPU 4. Memory 5 Input / Output Interface 6 Communication Unit 7 Output Devices 8 Input Devices 9 Sensors 10 Upper Management 20 Middle Class 30 Lower part 40 Force Sensor 50 Vibration Sensor 100 contacts

Claims

1. A skin condition evaluation method using a measurement device capable of acquiring contact information between a test surface of a test subject's hand and a contacted object based on a detection signal from a sensor, comprising: a first acquisition step of acquiring first contact information related to a plurality of first contacted objects by bringing the test surface of the subject's hand into contact with a plurality of first contacted objects each having a common second physical property among a plurality of physical properties that can affect a physical phenomenon occurring due to object contact and a different first physical property that is different from the second physical property, and performing an evaluation target action on each of the first contacted objects; a second acquiring step of acquiring second contact information about a plurality of second contacted objects by bringing the test surface of the subject's hand into contact with the plurality of second contacted objects that have the same first physical property but different second physical properties, and performing an evaluation target action on each of the plurality of second contacted objects; an evaluation step of evaluating a skin condition of the subject's hand based on the first contact information and the second contact information; A method for evaluating skin condition comprising:

2. In the evaluation step, a skin condition of the subject's hand is evaluated using at least a degree of variation between first contacted objects in the first contact information and a degree of variation between second contacted objects in the second contact information. The method for evaluating skin condition according to claim 1 .

3. One of the first physical property and the second physical property is surface texture or hardness, or the first physical property and the second physical property are surface texture and hardness. The method for evaluating skin condition according to claim 1 .

4. A plurality of contactors that mimic the flexibility of human fingers and have different physical properties or surface shapes, or both, that can affect physical phenomena that occur when an object is contacted, are used to perform the evaluation target operation on the plurality of first contacted objects and the plurality of second contacted objects, and evaluation information on the contact surface state of each contactor is obtained in advance based on contact information of each contactor; In the evaluation step, the previously acquired evaluation information is further used to classify the skin condition of the subject's hand. The method for evaluating a skin condition according to claim 1 .

5. A plurality of contactors that mimic the flexibility of human fingers and have different physical properties or surface shapes, or both, that can affect physical phenomena that occur when an object is contacted, are used to perform the evaluation target operation on the plurality of first contacted objects and the plurality of second contacted objects, and evaluation information on the contact surface state of each contactor is obtained in advance based on contact information of each contactor; In the evaluation step, a contact corresponding to the skin condition of the subject's hand is identified from the plurality of contacts by further using the evaluation information acquired in advance. The method for evaluating a skin condition according to claim 1 .

6. A plurality of contactors that mimic the flexibility of human fingers and have different physical properties or surface shapes, or both, that can affect physical phenomena that occur when an object is contacted, are used to perform the evaluation target operation on the plurality of first contacted objects and the plurality of second contacted objects, and evaluation information on the contact surface state of each contactor is obtained in advance based on contact information of each contactor; In the evaluation step, the previously acquired evaluation information is further used to output information about the cosmetic product or the cosmetic procedure according to the subject's sense of touch. The method for evaluating a skin condition according to claim 1 .

7. a third acquiring step of acquiring third contact information regarding a plurality of third contactable objects by bringing the test surface of the subject's hand into contact with the plurality of third contactable objects having the same first physical property and the second physical property but different surface shapes, and performing an evaluation target action on each of the third contactable objects; Further comprising: the plurality of first contacted objects have a common surface shape, the plurality of second contacted objects have a common surface shape, In the evaluation step, a skin condition of the subject's hand is evaluated based on the first contact information, the second contact information, and the third contact information. The method for evaluating a skin condition according to claim 1 .

8. the sensor and the measuring device, An evaluation system capable of executing the skin condition evaluation method according to claim 1 .

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