Bathing determination apparatus

Abstract

Provided is a bathing determination apparatus capable of enhancing accuracy in determining bathing of a wearer. Provided is a bathing determination apparatus comprising: a ring device configured to be fitted on a finger; and a storage medium. The ring device is provided with: a first temperature sensor; a second temperature sensor; an optical sensor that emits light toward a finger having the ring device fitted thereon and that receives diffused reflection light from the finger; a control unit that controls the first temperature sensor, the second temperature sensor, and the optical sensor; and one or more wiring boards that each have a surface facing the inner peripheral side and a surface facing the outer peripheral side. The first temperature sensor is disposed on the surface facing the inner peripheral side of one of the wiring boards, and the second temperature sensor is disposed on the surface facing the outer peripheral side of one of the wiring boards. The storage medium stores a program for causing a computer to implement: a bathing detection function for detecting that a wearer of the ring device has bathed on the basis of a first temperature measurement value measured by the first temperature sensor and a second temperature measurement value measured by the second temperature sensor; and a bathing-time data processing function for performing data processing based on an optical sensor measurement value measured by the optical sensor, when bathing has been detected by the bathing detection function.

Description

Bathing judgment device

[0001] The present invention relates to a hot water intake determination device.

[0002] A behavioral status analysis device that predicts the behavior of a wearer based on the wearer's body temperature and the outside air temperature measured by a wristwatch-type behavioral status monitor is known (see Patent Document 1). Patent Document 1 describes that if the outside air temperature measured by the behavioral status monitor remains at 42°C for a certain period of time, for example, 15 minutes, it can be assumed that the wearer of the behavioral status monitor has taken a bath. The outside air temperature is displayed on a bezel attached to the top of the body of the wristwatch-type behavioral status monitor.

[0003] Japanese Patent Application Laid-Open No. 2004-8471

[0004] If the criterion for determining whether someone has taken a bath is that the measured outside temperature remains at 42°C for a certain period of time, then if the water temperature is below 42°C, for example, around 38°C, then bathing cannot be detected. Furthermore, if the activity monitoring device is exposed to warm air from a fan heater or the like, it may be erroneously determined that the wearer has taken a bath. Furthermore, if the wearer bathes for a short period of time that is shorter than the certain period that serves as the bathing criterion, then bathing will not be determined. Furthermore, it is common for people to remove their wristwatches before taking a bath. If a wristwatch-type activity monitoring device is removed before taking a bath, it will be impossible to accurately determine whether or not the wearer has taken a bath.

[0005] An object of the present invention is to provide a hot water intake determination device that can improve the accuracy of determining whether a wearer is taking a hot water.

[0006] According to one aspect of the present invention, there is provided a bathing determination device comprising: a ring device configured to be worn on a finger; and a storage medium, wherein the ring device comprises: a first temperature sensor; a second temperature sensor; an optical sensor that emits light toward the finger on which the ring device is worn and receives diffusely reflected light from the finger; a control unit that controls the first temperature sensor, the second temperature sensor, and the optical sensor; and one or more wiring boards having a surface facing an inner circumference and a surface facing an outer circumference, wherein the first temperature sensor is arranged on the surface facing the inner circumference of one of the wiring boards, and the second temperature sensor is arranged on the surface facing the outer circumference of one of the wiring boards, and the storage medium stores a program that causes a computer to realize: a bathing detection function that detects that the wearer of the ring device has taken a bath based on a first temperature measurement value measured by the first temperature sensor and a second temperature measurement value measured by the second temperature sensor; and a bathing data processing function that processes data based on the optical sensor measurement value measured by the optical sensor when bathing is detected by the bathing detection function.

[0007] Biometric information can be collected by operating the optical sensor. The first temperature sensor is disposed on the inner peripheral surface of one of the wiring boards, and the second temperature sensor is disposed on the outer peripheral surface of one of the wiring boards. Therefore, the first temperature measurement value from the first temperature sensor tends to reflect the temperature of the wearer's finger, and the second temperature measurement value from the second temperature sensor tends to reflect the outside temperature. By detecting bathing based on both the first and second temperature measurements, the accuracy of bathing determination can be improved.

[0008] FIG. 1 is a block diagram of a hot water immersion determination device according to a first embodiment. FIG. 2A is a cross-sectional view of an internal member 20 arranged inside the ring device 10 to maintain the ring device's annular shape. FIG. 2B is a cross-sectional view of several components arranged along the outer periphery of the internal member 20 (FIG. 2A). FIG. 2C is a cross-sectional view of the ring device 10. FIGS. 3A, 3B, 3C, and 3D are graphs showing the time changes in the first temperature measurement value T1 and the second temperature measurement value T2 when the ring device 10 is worn and immersed in 40°C hot water, when the ring device 10 is covered with the other hand, when the palm of the hand wearing the ring device 10 is held over a heater, and when the back of the hand wearing the ring device 10 is held over a heater. FIGS. 4A, 4B, 4C, and 4D are graphs showing the time change rates (temperature change rates) of the first temperature measurement value T1 and the second temperature measurement value T2 shown in FIGS. 3A, 3B, 3C, and 3D, respectively. 5A and 5B are graphs showing the time changes of the first temperature measurement value T1 and the second temperature measurement value T2 during the period of immersion in hot water (bathing period Tb) and the period after leaving the bathtub and resting in a seated position (resting sitting period Tr). FIGS. 6A and 6B are graphs showing the time change rates of the first temperature measurement value T1 and the second temperature measurement value T2 shown in FIGS. 5A and 5B, respectively. FIGS. 7A and 7B are graphs showing the time changes of the first temperature measurement value T1, the second temperature measurement value T2, the pulse rate, and the peripheral blood circulation index when bathing for 10 minutes, leaving the bathtub, and resting in a seated position. FIGS. 8A and 8B are graphs showing the time changes of the pulse rate and HF when bathing for 10 minutes, leaving the bathtub, and resting in a seated position, similar to the cases of FIGS. 7A and 7B. FIG. 9 is a flowchart showing the procedure for realizing the bathing detection function 61 and the bathing evaluation function 62A. Fig. 10 is a flowchart showing other procedures for realizing the hot water entry detection function 61 and the hot water entry evaluation function 62A. Fig. 11 is a flowchart showing procedures for realizing the heat shock risk evaluation function 62B. Fig. 12 is a flowchart showing procedures for realizing the hot water entry effect evaluation function 62D (Fig. 1). Fig. 13 is a block diagram showing the locations where various functions of the hot water entry determination device according to a modified example of the first embodiment are realized.FIG. 14 is a block diagram of the ring device 10 of the hot water immersion determination device according to the third embodiment. FIG. 15 is a flowchart showing the procedure for implementing the heat shock risk assessment function 62B in the hot water immersion determination device according to the third embodiment. FIG. 16A is a graph showing the actual measured values ​​of the first temperature measurement T1 from the first temperature sensor 11 and the second temperature measurement T2 from the second temperature sensor 12 over time when the ring device 10 is worn on a finger and immersed in hot water at a temperature of 40°C. FIG. 16B is a graph showing the actual measured values ​​of the first temperature measurement T1 and the second temperature measurement T2 over time when the hot water temperature is set to 43°C. FIG. 17A is a graph showing the actual measured values ​​of the first temperature measurement T1 from the first temperature sensor 11 and the second temperature measurement T2 from the second temperature sensor 12 over time when the ring device 10 is worn on a finger and removed from hot water at a temperature of 40°C. FIG. 17B is a graph showing the actual measured values ​​of the first temperature measurement T1 and the second temperature measurement T2 over time when the hot water temperature is set to 43°C.

[0009] [First Embodiment] A hot water immersion determination device according to a first embodiment will be described with reference to Figures 1 to 12. Figure 1 is a block diagram of the hot water immersion determination device according to the first embodiment. The hot water immersion determination device according to the first embodiment includes a ring device 10, a storage medium 60 in a control terminal 50, and a storage medium 110 in a server 100. Examples of the storage medium 60 include non-volatile memory such as flash memory. Examples of the storage medium 110 include a hard disk drive (HDD) and a solid state drive (SSD). The ring device 10 is worn on a user's finger when in use. The control terminal 50 is an information terminal carried by the user wearing the ring device 10, and communicates data with the ring device 10.

[0010] For example, a general-purpose smartphone or smartwatch with a dedicated application program installed can be used as the control terminal 50. The storage medium 110 of the server 100 stores programs that enable a computer to implement various functions of the control terminal 50, such as a bathing detection function 61 and a bathing data processing function 62. These programs are downloaded from the server 100 to the control terminal 50 and installed.

[0011] The hot water immersion determination device according to the first embodiment can be considered to be comprised of the ring device 10 and a storage medium 60 of the control terminal 50 onto which programs for implementing various functions have been downloaded. Alternatively, the hot water immersion determination device according to the first embodiment can be considered to be comprised of the ring device 10 and a storage medium 110 of the server 100 onto which programs for implementing various functions have been stored. Alternatively, the hot water immersion determination device according to the first embodiment can be considered to be comprised of the ring device 10 and a removable storage medium, such as an optical disk, memory card, or USB memory, onto which programs for implementing various functions have been stored. If the control terminal 50 is a terminal dedicated to controlling the ring device 10, the hot water immersion determination device according to the first embodiment can be considered to be comprised of the ring device 10 and the control terminal 50.

[0012] The ring device 10 includes a first temperature sensor 11, a second temperature sensor 12, an optical sensor 13, a control unit 14, a memory 15, a notifier 16, a battery 17, a first communication unit 18, and an acceleration gyro sensor 19, all attached to an annular member configured to be worn on a finger. The battery 17 is rechargeable, for example, via a wireless charging module (not shown).

[0013] Next, the structure of the ring device 10 will be described with reference to Figures 2A, 2B, and 2C. Figure 2A is a cross-sectional view of an internal member 20 that is placed inside the ring device 10 and maintains the annular shape of the ring device. The internal member 20 has an annular shape that follows a substantial circumference. The internal member 20 is made of, for example, a non-transparent resin such as ABS or polycarbonate. The internal member 20 is manufactured by injection molding.

[0014] The first opening 20A and the second opening 20B are provided at different positions in the circumferential direction of the internal member 20. The internal member 20 may have a shape that follows the outer periphery of an ellipse, or a shape that follows a closed curve without an inflection point, in addition to a circular shape. For example, a shape that follows the outer periphery of the cross-sectional shape of a human finger is preferable. The internal member 20 may also have a partially open C-shape.

[0015] 2B is a cross-sectional view of multiple components arranged along the outer periphery of internal member 20 (FIG. 2A). A wiring board consisting of rigid portions 21, 22, and 23 and flexible portions 24, 25, and 26, and battery 17 are arranged along the outer periphery of internal member 20 (FIG. 2A). Battery 17 and rigid portion 21 are connected by flexible portion 24, rigid portions 21 and 22 are connected by flexible portion 25, and rigid portions 22 and 23 are connected by flexible portion 26.

[0016] The flexible portions 24, 25, and 26 have flexibility that allows them to deform along the outer circumferential surface of the internal member 20. The rigid portions 21, 22, and 23 have higher rigidity than the flexible portions 24, 25, and 26 and do not deform easily. As a wiring board including the rigid portions 21, 22, and 23 and the flexible portions 24, 25, and 26, for example, a rigid-flexible board can be used.

[0017] Rigid portions 22 and 23 are disposed at the positions of the first opening 20A and the second opening 20B (FIG. 2A), respectively. The second temperature sensor 12 is mounted on the outer peripheral surface of the rigid portion 21. The first light-emitting element 13A and the light-receiving element 13C are mounted on the inner peripheral surface of the rigid portion 22. The first temperature sensor 11 and the second light-emitting element 13B are mounted on the inner peripheral surface of the rigid portion 23, and the control unit 14 and the acceleration gyro sensor 19 are mounted on the outer peripheral surface. For example, surface-mounted thermistors can be used as the first temperature sensor 11 and the second temperature sensor 12. The first light-emitting element 13A, the second light-emitting element 13B, and the light-receiving element 13C constitute the optical sensor 13 (FIG. 1).

[0018] Although not shown in the cross section shown in FIG. 2B, the memory 15 and the first communication unit 18 (FIG. 1) are mounted on either the rigid parts 21, 22, 23 or the flexible parts 24, 25, 26.

[0019] 2C is a cross-sectional view of the ring device 10. A wiring board consisting of rigid portions 21, 22, and 23 and flexible portions 24, 25, and 26, and a battery 17 are arranged along the outer circumferential surface of the internal member 20 and fixed to the internal member 20. The first light-emitting element 13A and the light-receiving element 13C are arranged in the first opening 20A, and the second light-emitting element 13B and the first temperature sensor 11 are arranged in the second opening 20B. Because the internal member 20 is made of a non-translucent material, it is possible to prevent ambient light, such as illumination light or sunlight, from unintentionally entering the light-receiving element 13C.

[0020] The internal member 20, the battery 17, and the multiple components mounted on the wiring board are covered with a transparent resin member 30. For example, epoxy resin, silicone resin, urethane resin, polycarbonate, etc. can be used as the transparent resin member 30. The inner peripheral surface of the transparent resin member 30 forms the inner peripheral surface of the ring device 10. An annular outer member 31 is in close contact with the outer peripheral surface of the transparent resin member 30.

[0021] It is preferable to form raised portions 30A and 30B that are raised relative to the surrounding inner circumferential surface at positions on the inner circumferential surface of the ring device 10 corresponding to the locations where the first light-emitting element 13A and the second light-emitting element 13B are arranged. This improves the adhesion between the inner circumferential surface in the area where the first light-emitting element 13A and the second light-emitting element 13B are arranged and the surface of the body. Furthermore, it is also possible to form raised portions on the inner circumferential surface at positions corresponding to the location where the light-receiving element 13C is arranged.

[0022] Although not shown in Fig. 2C, a light-shielding wall may be disposed between the first light-emitting element 13A and the light-receiving element 13C. By disposing the light-shielding wall, it is possible to suppress light emitted from the first light-emitting element 13A from being directly incident on the light-receiving element 13C without passing through the living body. This light-shielding wall is preferably black.

[0023] The outer member 31 may be made of, for example, metal, ceramic, resin, etc. Preferably, the metal material is biocompatible and less likely to cause allergies. Examples of metal materials include stainless steel, titanium, titanium alloy, cobalt-chromium alloy, tantalum, magnesium alloy, gold, silver, platinum, etc. Examples of ceramic materials include zirconia (zirconium dioxide), aluminum nitride, aluminum oxide, silicon carbide, silicon nitride, etc. Examples of resin materials include ABS, polycarbonate, etc.

[0024] Next, the positional relationship of the first temperature sensor 11, the second temperature sensor 12, and the optical sensor 13 in the circumferential direction will be described. The inner peripheral surface of the ring device 10 is divided into two regions, a first arc-shaped region R1 and a second arc-shaped region R2, each having the same circumferential length. The regions are divided so that the distribution range RS of the optical sensor 13 is located at the center of the first arc-shaped region R1 in the circumferential direction. The first temperature sensor 11 is located within the first arc-shaped region R1 in the circumferential direction, and the second temperature sensor 12 is located within the second arc-shaped region R2 in the circumferential direction. When determining the "perimeter," it is preferable to assume that the raised portions 30A and 30B are not provided. For example, a closed curve that makes one revolution along the inner peripheral surface may be approximated by a convex closed curve, and the length along the convex closed curve may be defined as the "perimeter."

[0025] Next, the functions of the ring device 10 will be described. <First Temperature Sensor, Second Temperature Sensor> The first temperature sensor 11 (FIG. 2C) is arranged on a surface facing the inner periphery of a wiring board built into the ring device 10, and the second temperature sensor 12 (FIG. 2C) is arranged on a surface facing the outer periphery of a wiring board built into the ring device 10. As an example, the first temperature sensor 11 may be located closer to the inner periphery than the midpoint between the inner and outer periphery of the ring device 10, and the second temperature sensor 12 (FIG. 2C) may be located closer to the outer periphery than the midpoint between the inner and outer periphery of the ring device 10.

[0026] There are more blood vessels on the ventral side of a finger than on the dorsal side. As will be described later, in order to collect biometric information such as photoplethysmographic information using the optical sensor 13, the ring device 10 is worn on the finger so that the optical sensor 13 is located on the ventral side of the finger where there are more blood vessels. That is, the first arc-shaped region R1 is located on the ventral side of the finger, and the second arc-shaped region R2 is located on the dorsal side of the finger.

[0027] The temperature measured by the first temperature sensor 11 located on the pad side of the finger (hereinafter referred to as the first temperature measurement) is likely to reflect the temperature of the wearer's finger. Furthermore, because the first temperature sensor 11 is located on a surface facing the inner periphery of the rigid portion 23, the temperature of the finger is more likely to be reflected in the first temperature measurement. Conversely, the temperature measured by the second temperature sensor 12 located on the dorsal side of the finger (hereinafter referred to as the second temperature measurement) is more likely to reflect the external temperature. Furthermore, because the second temperature sensor 12 is located on a surface facing the outer periphery of the rigid portion 23, the external temperature is more likely to be reflected in the second temperature measurement. The first and second temperature measurement values ​​are input to the control unit 14.

[0028] When the ring device 10 is worn on a finger, the inner circumferential surface of the ring device 10 comes into contact with the body surface, and the first temperature sensor 11 is thermally coupled to the body surface. This allows the first temperature sensor 11 to accurately measure the temperature of the finger. It is preferable to prevent an air layer with low thermal conductivity from being interposed between the body surface and the first temperature sensor 11. For example, the first temperature sensor 11 may be tightly covered with an insulating resin or paste. Alternatively, the first temperature sensor 11 may be thinly covered with an insulating resin or paste, and the surface may be covered with a conductive resin or paste with higher thermal conductivity.

[0029] In order to measure the external temperature with high precision using the second temperature sensor 12, it is preferable to prevent an air layer from being present between the second temperature sensor 12 and the outer peripheral surface of the ring device 10.

[0030] <Optical Sensor> The first light-emitting element 13A and the second light-emitting element 13B (FIG. 2C) of the optical sensor 13 emit light toward the finger on which the ring device is worn. The diffused light reflected from the finger is received by the light-receiving element 13C (FIG. 2C).

[0031] Next, the operation of the optical sensor 13 (FIG. 1) consisting of the first light-emitting element 13A, the second light-emitting element 13B, and the light-receiving element 13C will be described in more detail. The optical sensor 13 operates under the control of the control unit 14.

[0032] The first light-emitting element 13A and the second light-emitting element 13B each emit measurement light toward the space inside the ring device 10. The first light-emitting element 13A emits light in a wavelength range from blue to yellow-green (preferably a wavelength range of 500 nm to 550 nm), and the second light-emitting element 13B emits light in a red wavelength range (preferably a wavelength range of 650 nm to 700 nm) or near-infrared light (preferably a wavelength range of 850 nm to 950 nm). The light-receiving element 13C receives light arriving from the space inside the ring device 10 and outputs an electrical signal corresponding to the light intensity. The transparent resin member 30 transmits the light emitted from the first light-emitting element 13A and the second light-emitting element 13B.

[0033] For example, a light emitting diode (LED) or a vertical cavity surface emitting laser (VCSEL) can be used as the first light emitting element 13A and the second light emitting element 13B. For example, a photodiode or a phototransistor can be used as the light receiving element 13C.

[0034] The light emitted from the first light-emitting element 13A and the second light-emitting element 13B passes through the living body, is diffusely reflected, and is incident on the light-receiving element 13C. Biometric information, such as photoplethysmographic information, can be acquired based on the intensity of the light incident on the light-receiving element 13C. When measuring the photoplethysmographic information, for example, the first light-emitting element 13A and the second light-emitting element 13B are alternately operated at a sampling rate of 50 Hz to 1000 Hz. The duty ratio of the light-emitting time of the first light-emitting element 13A and the second light-emitting element 13B may be, for example, 0.1% to 10%.

[0035] Because light in the blue to yellow-green wavelength range emitted by the first light-emitting element 13A is absorbed relatively well by living bodies, the distance between the first light-emitting element 13A and the light-receiving element 13C is preferably 1 mm or more and 3 mm or less. To achieve this distance, the first light-emitting element 13A and the light-receiving element 13C are disposed within the same first opening 20A. Because light in the red or near-infrared wavelength range emitted by the second light-emitting element 13B is absorbed relatively little by living bodies, the distance between the second light-emitting element 13B and the light-receiving element 13C is preferably 5 mm or more and 20 mm or less. To achieve this distance, the second light-emitting element 13B is disposed within a second opening 20B that is different from the first opening 20A in which the light-receiving element 13C is disposed.

[0036] The photoelectric pulse wave information acquired by operating the first light-emitting element 13A and the light-receiving element 13C contains a larger proportion of information from shallower regions of the skin, while the photoelectric pulse wave information acquired by operating the second light-emitting element 13B and the light-receiving element 13C contains a larger proportion of information from deeper regions of the skin. The absorption rate of light in the red to near-infrared wavelength range varies depending on the oxygen saturation level in the blood. For example, the second light-emitting element 13B may be provided with the function of emitting light in the red wavelength range and light in the near-infrared range, and information regarding oxygen saturation may be acquired by operating the second light-emitting element 13B and the light-receiving element 13C. Alternatively, a third light-emitting element may be provided in addition to the second light-emitting element 13B, with one light-emitting element emitting light in the red wavelength range and the other light-emitting element emitting light in the near-infrared range.

[0037] <Memory> The memory 15 (FIG. 1) stores the first temperature measurement value obtained by the first temperature sensor 11, the second temperature measurement value obtained by the second temperature sensor 12, photoplethysmographic information measured by the optical sensor 13, and the like.

[0038] <Notifier> The notifier 16 ( FIG. 1 ) is controlled by the control unit 14 to notify the wearer of the ring device 10 of various information. For example, the first light-emitting element 13A can also serve as the notifier 16. Furthermore, if the emission wavelength of the second light-emitting element 13B is in the red wavelength range, the second light-emitting element 13B can also serve as the notifier 16. For example, the first light-emitting element 13A and the second light-emitting element 13B can be made to emit light intermittently in a different emission pattern from that used when measuring photoplethysmographic information to notify the wearer of some information. Alternatively, the emission intensity of the first light-emitting element 13A and the second light-emitting element 13B may be made different from that used when measuring photoplethysmographic information. For example, the emission intensity can be changed by changing the duty ratio at which the first light-emitting element 13A and the second light-emitting element 13B blink or by changing the drive current.

[0039] As the notifier 16, a vibration generator, a sound generator, etc. may be used in addition to the light emitting element.

[0040] <First Communication Unit> The first communication unit 18 ( FIG. 1 ) receives control from the control unit 14 and performs wireless communication with the control terminal 50 using a wireless communication method that complies with a known wireless communication standard. Examples of wireless communication standards include Bluetooth Low Energy (BLE), Near Field Communication (NFC), and Wireless Fidelity (WiFi).

[0041] <Acceleration gyro sensor> The acceleration gyro sensor 19 (Fig. 1) measures acceleration in three orthogonal axis directions and angular velocity around three orthogonal axes. The measurement results are input to the control unit 14. The measurement results by the acceleration gyro sensor 19 can be used to determine whether the wearer is at rest.

[0042] Next, an example of a manufacturing method for the ring device 10 will be described. First, the internal member 20 is produced by resin molding. The second temperature sensor 12 is mounted on the rigid portion 21, the first light-emitting element 13A and the light-receiving element 13C are mounted on the rigid portion 22, and the first temperature sensor 11, the second light-emitting element 13B, the control unit 14, and the acceleration gyro sensor 19 are mounted on the rigid portion 23. The battery 17 is connected to the flexible portion 24.

[0043] The rigid portions 21, 22, 23, the flexible portions 24, 25, 26, and the battery 17 are fixed to the outer peripheral surface of the internal member 20. For example, the internal member 20 is formed with portions shaped to fit the rigid portions 21, 22, 23, etc., and the rigid portions 21, 22, 23, etc. are fitted into the internal member 20. Alternatively, they may be fixed with double-sided tape, adhesive, etc.

[0044] A transparent resin is filled into the first opening 20A and the second opening 20B of the internal member 20. This transparent resin may be, for example, an epoxy-based, silicone-based, urethane-based, polycarbonate, or other resin. Then, the internal member 20, rigid portions 21, 22, and 23, flexible portions 24, 25, and 26, and battery 17 are assembled into the external member 31, and these components are sealed with a transparent resin member 30.

[0045] Next, the functions of the control terminal 50 ( FIG. 1 ) will be described. The control terminal 50 includes a processing unit 51, a display 52, a sound generator 53, a vibration generator 54, a second communication unit 55, and a storage medium 60. The processing unit 51 is configured as a computer including a microcontroller unit (MCU) and the like. The processing unit 51 executes various programs stored in the storage medium 60, thereby realizing various functions of the control terminal 50.

[0046] The display 52 displays the processing results of the processing unit 51 as a text message, an image, or the like in response to a command from the processing unit 51. The display 52 may also be configured as a touch panel, for example, and may also serve as an input device. The sound generator 53 produces various sounds and voices in response to a command from the processing unit 51. The vibration generator 54 generates vibrations in response to a command from the processing unit 51. The second communication unit 55 wirelessly communicates with the ring device 10 by the processing unit 51 executing a program that realizes a second communication function 66 stored in the storage medium 60.

[0047] The storage medium 60 stores a program for implementing a bathing detection function 61, a program for implementing a bathing data processing function 62, a program for implementing an input / output function 65, and a program for implementing a second communication function 66. The bathing data processing function 62 includes a bathing evaluation function 62A, a heat shock risk evaluation function 62B, a bathing frequency calculation function 62C, and a bathing effect evaluation function 62D.

[0048] These functions will be described next. <Input / Output Function> First, the input / output function 65 will be described. The input / output function 65 provides a user interface. For example, the input / output function 65 includes a function for receiving various commands input by the wearer of the ring device 10 and a function for outputting various processing results to the display 52.

[0049] <Bathing Water Detection Function> Next, the bathing water detection function 61 will be described. The first temperature measurement value measured by the first temperature sensor 11 and the second temperature measurement value measured by the second temperature sensor 12 are transmitted from the ring device 10 to the control terminal 50. The processing unit 51 executes a program that realizes the bathing water detection function 61, thereby detecting that the wearer of the ring device 10 has taken a bath, based on the first temperature measurement value and the second temperature measurement value received from the ring device 10.

[0050] Next, a specific example of a method for detecting bathing will be described with reference to Figures 3A to 4D. In the following description, an example will be described in which the ring device 10 is worn on a finger such that the area of ​​the inner circumferential surface where the first temperature sensor 11 is located is in contact with the pad side of the finger, and the second temperature sensor 12 is oriented toward the dorsal side of the finger. For example, when the ring device 10 (Figure 2C) is worn on a finger, the first temperature sensor 11 is positioned on the pad side of the finger, and the second temperature sensor 12 is positioned on the dorsal side of the finger, as viewed from an imaginary plane that is perpendicular to a line extending from the pad side to the dorsal side of the finger and passes through the center of the ring device 10.

[0051] 3A, 3B, 3C, and 3D are graphs showing the time changes of the first temperature measurement value T1 and the second temperature measurement value T2 when the ring device 10 is worn and immersed in 40°C hot water, when the ring device 10 worn on a finger is covered with the other hand, when the palm of the hand wearing the ring device 10 is held over a heater, and when the back of the hand wearing the ring device 10 is held over a heater. Figures 4A, 4B, 4C, and 4D are graphs showing the time change rate (temperature change speed) of the first temperature measurement value T1 and the second temperature measurement value T2 shown in Figures 3A, 3B, 3C, and 3D, respectively. In the graphs from Figure 3A to Figure 4D, the solid line and dashed line indicate the first temperature measurement value T1 and the second temperature measurement value T2, respectively.

[0052] The horizontal axis of each graph represents the elapsed time from the start of each operation in units of seconds. Negative values ​​for the elapsed time indicate the period before the start of each operation. The vertical axis of the graphs in Figures 3A, 3B, 3C, and 3D represents the temperature in units of °C, and the vertical axis of the graphs in Figures 4A, 4B, 4C, and 4D represents the temperature change rate in units of °C / s.

[0053] In both cases, the first temperature measurement value T1 and the second temperature measurement value T2 increase from the start of each action. When the ring device 10 is covered with the hand ( FIGS. 3B and 4B ), the ring device 10 is warmed by body heat, which is lower than the temperature of the hot water or heater, so the rate of temperature increase is slower than when the ring device 10 is immersed in hot water of about 40°C or exposed to a heat source such as a heater. Furthermore, when the ring device 10 is worn and immersed in hot water ( FIGS. 3A and 4A ) and when the ring device 10 is covered with the hand ( FIGS. 3A and 4A ), the pad and dorsal sides of the fingers are warmed evenly, so the difference in the rate of increase (rate of temperature change) between the first temperature measurement value T1 and the second temperature measurement value T2 is small.

[0054] When the palm of the hand is held over the heater ( FIGS. 3C and 4C ), the first temperature sensor 11 faces the heater, so the temperature change rate of the first measured temperature value T1 is faster than the temperature change rate of the second measured temperature value T2. Conversely, when the back of the hand is held over the heater ( FIGS. 3D and 4D ), the second temperature sensor 12 faces the heater, so the temperature change rate of the second measured temperature value T2 is faster than the temperature change rate of the first measured temperature value T1. In contrast, when the ring device 10 is worn and immersed in 40°C hot water ( FIGS. 3A and 4A ), the temperature change rates of both the first measured temperature value T1 and the second measured temperature value T2 are faster in the period from 0 seconds to 10 seconds compared to the other cases. This is because when the entire ring device 10 is immersed in hot water, heat is more easily transferred to the entire ring device 10 than through thermal radiation from a heat source such as a heater.

[0055] Therefore, bathing can be detected based on the rate of temperature change between the first temperature measurement value T1 and the second temperature measurement value T2. The bathing detection function 61 determines that the wearer has taken a bath, for example, when the maximum value of the rate of temperature change for both the first temperature measurement value T1 and the second temperature measurement value T2 exceeds a first threshold. As shown in FIG. 4A , when the ring device 10 is worn and immersed in hot water, the maximum values ​​of the rate of temperature change for the first temperature measurement value T1 and the second temperature measurement value T2 are both 0.15°C / s or greater. In the cases of FIGS. 4B , 4C , and 4D , the maximum value of the rate of temperature change for at least one of the first temperature measurement value T1 and the second temperature measurement value T2 is less than 0.15°C / s. Therefore, by setting the first threshold to, for example, 0.15°C / s, bathing can be distinguished from covering the ring device 10 with a hand and holding a heater over the hand wearing the ring device 10.

[0056] Furthermore, a condition that the maximum value of the rate of change of the second temperature measurement value T2 is greater than the maximum value of the rate of change of the first temperature measurement value T1 may be added to the conditions for bathing detection. The first temperature measurement value T1 measured by the first temperature sensor 11, which is closer to the finger, is more susceptible to the influence of the finger's thermal capacity than the second temperature measurement value T2. Therefore, when bathing, the rate of change of the second temperature measurement value T2 is faster than the rate of change of the first temperature measurement value T1. Taking this difference in temperature change rate into account can improve the accuracy of bathing detection. For example, a condition that the difference between the maximum rate of change of the second temperature measurement value T2 and the maximum rate of change of the first temperature measurement value T1 is greater than or equal to a second threshold value can be added to the bathing detection condition.

[0057] 5A to 6B, the bathing detection function 61 will be further described. The bathing detection function 61 includes a function for detecting when the wearer enters the bath, as well as a function for detecting when the wearer leaves the bathtub.

[0058] Figures 5A and 5B are graphs showing the time changes of the first temperature measurement value T1 and the second temperature measurement value T2 during the period of immersion in hot water (bathing period Tb) and the subsequent period of resting in a seated position after leaving the bathtub (sitting rest period Tr). Figures 6A and 6B are graphs showing the time change rates of the first temperature measurement value T1 and the second temperature measurement value T2 shown in Figures 5A and 5B, respectively. Figures 5A and 6A show the case where the water temperature is approximately 40°C, and Figures 5B and 6B show the case where the water temperature is approximately 43°C.

[0059] The horizontal axis of the graphs in Figures 5A to 6B represents elapsed time in minutes, the vertical axis of the graphs in Figures 5A and 5B represents temperature in degrees Celsius, and the vertical axis of the graphs in Figures 6A and 6B represents the rate of temperature change in degrees Celsius / s. The solid and dashed lines in these graphs represent the first and second measured temperature values ​​T1 and T2, respectively.

[0060] The temperature change rate shown in Figures 6A and 6B indicates the rate of change of temperature measured at a sampling rate of 20 Hz over 5 seconds. In other words, if the i-th measurement value is denoted as T(i), the temperature change rate ΔT shown in Figures 6A and 6B can be calculated using the following formula: ΔT = (T(i+100) - T(i)) / 5

[0061] When measuring the temperature at both water temperatures of approximately 40°C and 43°C, the subject entered the bath with their shoulders out of the water, dried themselves off after leaving the bathtub, moved to another room, and sat in a chair and remained at rest for approximately 15 minutes. The finger wearing the ring device 10 was kept at heart height while bathing and sitting at rest.

[0062] 5A to 6B, when the wearer enters the bathtub, the first temperature measurement value T1 and the second temperature measurement value T2 rise sharply, and when the wearer leaves the bathtub, the first temperature measurement value T1 and the second temperature measurement value T2 drop sharply. The first temperature measurement value T1 during the quiet sitting period Tr is higher than before entering the bathtub.

[0063] The hot water detection condition may be that the temperature change rate of the second temperature measurement value T2 exceeds a threshold higher than the first threshold, in addition to the first and second temperature measurement values ​​T1 and T2 both exceeding the first threshold. From the measurement results shown in Figures 6A and 6B, it can be seen that the threshold higher than the first threshold can be set to, for example, 0.20°C / s.

[0064] Furthermore, when the minimum value of the temperature change rate of the first temperature measurement value T1 and the second temperature measurement value T2 falls below a third threshold, it can be determined that the wearer has left the bathtub. Here, since the temperature change rate is negative, the minimum value of the temperature change rate falling below the third threshold corresponds to the maximum value of the absolute value of the temperature change rate exceeding the absolute value of the third threshold. From the measurement results shown in Figures 6A and 6B, it can be seen that the third threshold can be set to, for example, 0.07°C / s.

[0065] <Bathing Data Processing Function> Next, the bathing data processing function 62 ( FIG. 1 ) will be described. The processing unit 51 executes a program that realizes the bathing data processing function 62 when bathing detection function 61 detects bathing. By executing the program that realizes the bathing data processing function 62, the processing unit 51 performs various data processing based on the optical sensor measurement value (photoelectric pulse wave information) measured by the optical sensor 13. The bathing data processing function 62 includes a bathing evaluation function 62A, a heat shock risk evaluation function 62B, a bathing frequency calculation function 62C, and a bathing effect evaluation function 62D. Next, these functions will be described.

[0066] <Bathing evaluation function> The processing unit 51 (Figure 1) executes a program that realizes the bathing evaluation function 62A (Figure 1), thereby calculating the pulse rate based on the optical sensor measurement value, and determining whether the bathing was appropriate or not based on the calculated pulse rate and the calculated value of an index reflecting peripheral blood circulation (hereinafter referred to as peripheral blood circulation index).

[0067] Immersing in water that is too hot stimulates the sympathetic nervous system, increasing the pulse rate. As the pulse rate increases, blood pressure also rises. If the pulse rate is too high, the water temperature is likely to be inappropriate. Immersing in water that is too hot also causes peripheral blood vessels to constrict. This leads to a decrease in peripheral blood circulation indices. If the peripheral blood circulation indices decrease significantly, the water temperature is likely to be inappropriate. In this way, pulse rate and peripheral blood circulation indices are useful indicators for determining whether bathing was appropriate.

[0068] As the peripheral blood circulation index, for example, the index described as a "peripheral blood pressure index" in the specification of International Publication No. 2023 / 1894483 can be used. As an example, the reciprocal of the full width at half maximum of the first peak that appears within one beat of the velocity pulse wave information obtained by first-order differentiation of the photoelectric pulse wave information measured by the optical sensor 13 can be used.

[0069] The pulse rate also fluctuates due to body movement. To reduce the influence of body movement, it is advisable to determine the presence or absence of body movement based on the measurement results of the acceleration gyro sensor 19, and calculate the pulse rate after it is detected that no significant body movement has occurred. Furthermore, since the pulse rate tends to temporarily increase for several tens of seconds after body movement, the pulse rate may be calculated after several tens of seconds have passed since body movement was no longer detected.

[0070] The peripheral blood circulation index may change depending on the height from the heart to the finger wearing the ring device 10. For this reason, it is preferable to determine whether bathing is appropriate or not based primarily on changes in pulse rate, and to use changes in the peripheral blood circulation index as a secondary indicator.

[0071] 7A and 7B are graphs showing the time course of the first temperature measurement value T1, the second temperature measurement value T2, the pulse rate, and the peripheral blood circulation index when a subject bathes in the bathtub for 10 minutes, then exits the bathtub and sits and rests. Figures 7A and 7B show the cases where the bath temperature is 40°C and 43°C, respectively. The horizontal axis of the graphs in Figures 7A and 7B represents elapsed time in minutes, the left vertical axis represents pulse rate in bpm and temperature in °C, and the right vertical axis represents the peripheral blood circulation index in arbitrary units. In Figures 7A and 7B, the period of bathing is labeled Tb, and the period of sitting and resting is labeled Tr.

[0072] 7A and 7B, the subject entered the bath with their shoulders out of the water, then dried themselves off after leaving the bathtub, moved to another room, and sat in a chair and remained at rest for approximately 15 minutes. The finger wearing the ring device 10 was held at heart height while bathing and while sitting at rest.

[0073] When the water temperature is 40°C (Fig. 7A), the peripheral blood circulation index is maintained at about 10 during both the bathing period Tb and the sitting-at-rest period Tr. The pulse rate during the sitting-at-rest period Tr is lower than the pulse rate during the bathing period Tb. This means that the peripheral blood vessels remain dilated even after the subject leaves the bathtub.

[0074] In contrast, when the water temperature is 43°C (Figure 7B), during the bathing period Tb, the pulse rate increases over time, and the peripheral blood circulation index gradually decreases from 8. The increase in pulse rate reaches 30 bpm. Furthermore, during the sitting-at-rest period Tr, it takes a long time for the pulse rate to return to the value before bathing, and the peripheral blood circulation index is also lower than when the water temperature is 40°C. Thus, when the water temperature is 43°C, the pulse rate remains high and the peripheral blood circulation index remains low even during the sitting-at-rest period Tr compared to when the water temperature is 40°C.

[0075] 8A and 8B are graphs showing the time course of pulse rate and HF when a subject soaks in a bathtub for 10 minutes, then exits the bathtub and rests in a seated position, similar to the cases of FIGS. 7A and 7B. HF is one of the heart rate variability parameters, and is the power spectrum of the time waveform of the heart rate in the frequency band of 0.15 Hz to 0.4 Hz. The solid line in the graphs of FIGS. 8A and 8B indicates the pulse rate, and the dashed line indicates the HF. FIGS. 8A and 8B show the cases where the bath temperature is 40°C and 43°C, respectively. The horizontal axis of the graphs of FIGS. 8A and 8B represents elapsed time in minutes, the left vertical axis represents the pulse rate in bpm, and the right vertical axis represents the HF in ms. ２ ].

[0076] It can be seen that when the water temperature is 40°C, HF is higher during both the bathing period Tb and the sitting period Tr compared to when the water temperature is 43°C. A high HF indicates that the parasympathetic nervous system is dominant. It can be inferred that when the water temperature is 40°C, the subject is more relaxed than when the water temperature is 43°C.

[0077] Therefore, if the pulse rate gradually increases or the peripheral blood circulation index gradually decreases after bathing is detected, as shown in Figure 7B, it can be determined that bathing was inappropriate. In this way, it is possible to evaluate whether bathing was appropriate based on the trends in the time changes in the pulse rate and peripheral blood circulation index after bathing is detected.

[0078] In order to evaluate whether bathing is appropriate, the presence or absence of arrhythmia may be detected in addition to pulse rate and peripheral blood circulation index. Arrhythmia can be detected by analyzing photoplethysmographic information. If arrhythmia is detected, bathing should be determined to be inappropriate.

[0079] FIG. 9 is a flowchart showing the procedure for realizing the bathing detection function 61 and the bathing evaluation function 62A.

[0080] First, the control unit 14 (FIG. 1) of the ring device 10 starts temperature measurement using the first temperature sensor 11 and the second temperature sensor 12 (step SA1). This measurement is performed intermittently at a predetermined cycle, for example, between 0.1 seconds and 10 seconds. The control unit 14 transmits the measurement results to the control terminal 50.

[0081] The processing unit 51 of the control terminal 50 determines whether the wearer of the ring device 10 has taken a bath based on the first temperature measurement value T1 from the first temperature sensor 11 and the second temperature measurement value T2 from the second temperature sensor 12 (step SA2). If taking a bath is not detected, this determination process is repeated at a predetermined interval of about 10 seconds. If taking a bath is detected, the control terminal 50 notifies the ring device 10 that taking a bath has been detected.

[0082] Upon receiving this notification, the ring device 10 activates the optical sensor 13 and acquires photoplethysmographic information for a predetermined period (step SA3). The optical sensor 13 operates intermittently to reduce power consumption. However, blood-related biological information, such as photoplethysmographic information, is strongly affected by body movement. To eliminate the influence of body movement, it is preferable to acquire photoplethysmographic information only when a resting state is detected. The resting state can be detected, for example, based on the measurement results of the acceleration gyro sensor 19 (FIG. 1). After acquiring the photoplethysmographic information, the ring device 10 stops measuring the temperature using the first temperature sensor 11 and the second temperature sensor 12, and further stops the operation of the optical sensor 13 (step SA4).

[0083] The ring device 10 then transmits the photoplethysmographic information to the control terminal 50. The processing unit 51 of the control terminal 50 calculates the change in pulse rate over time based on the photoplethysmographic information received from the ring device 10 (step SA5). The pulse rate is calculated based on the photoplethysmographic information within a predetermined calculation unit time, for example. The change in pulse rate over time is determined by shifting this calculation unit time by a predetermined time interval.

[0084] Next, the processing unit 51 of the control terminal 50 determines whether bathing was appropriate based on the change in pulse rate over time (step SA6). This determination can be made using the method described with reference to Figures 7A to 8B, for example. The processing unit 51 then executes the input / output function 65 to output the result of the bathing appropriateness determination to the display 52 (Figure 1) (step SA7). Furthermore, the processing unit 51 may transmit information indicating the bathing appropriateness determination result to the ring device 10, and the control unit 14 (Figure 1) of the ring device 10 may operate the notifier 16 to notify the wearer of the determination result.

[0085] FIG. 10 is a flowchart showing another procedure for realizing the bathing detection function 61 and the bathing evaluation function 62A.

[0086] The start of temperature measurement by the first temperature sensor 11 and the second temperature sensor 12 (step SB1) and the process of determining whether or not a person is taking a bath (step SB2) are the same as the processes in steps SA1 and SA2 shown in Fig. 9. When taking a bath is detected, in the procedure shown in Fig. 9, the optical sensor 13 is operated for a predetermined time to acquire photoplethysmographic information (step SA3), and then temperature measurement by the first temperature sensor 11 and the second temperature sensor 12 and the operation of the optical sensor 13 are stopped. In contrast, in the procedure shown in Fig. 10, when taking a bath is detected, the optical sensor 13 is operated to start acquiring photoplethysmographic information (step SB3).

[0087] The first temperature sensor 11 and the second temperature sensor 12 continue to measure the temperature, and the measurement results are sent to the control terminal 50. The processing unit 51 of the control terminal 50 executes a program that realizes the bathtub entry detection function 61 (FIG. 1) to determine whether the wearer has left the bathtub (step SB4). If exit from the bathtub is not detected, the process of determining whether the wearer has left the bathtub is repeated at a predetermined interval. The method of determination described with reference to FIGS. 5A to 6B can be used to determine whether the wearer has left the bathtub.

[0088] When exit from the bathtub is detected, the control terminal 50 notifies the ring device 10 of the detection of exit from the bathtub. Upon receiving this notification, the ring device 10 stops temperature measurement by the first temperature sensor 11 and the second temperature sensor 12 and operation of the optical sensor 13 (step SB5). The subsequent processing of steps SB6, SB7, and SB8 is the same as the processing of steps SA5, SA6, and SA7 shown in Figure 9. Note that after exit from the bathtub is detected, instead of stopping operation of the optical sensor 13, the frequency of operation may be reduced to continue acquiring photoplethysmographic information.

[0089] In the procedure shown in FIG. 10, the detection of exit from the bathtub is used as a trigger to stop the operation of the first temperature sensor 11, the second temperature sensor 12, and the light sensor 13.

[0090] <Heat Shock Risk Assessment Function> Next, the heat shock risk assessment function 62B ( FIG. 1 ) will be described. The processing unit 51 executes a program that realizes the heat shock risk assessment function 62B, thereby comparing the second temperature measurement value T2 before bathing with the second temperature measurement value T2 after bathing, and determining the degree of risk of heat shock.

[0091] A large difference between the air temperature in the bathroom or changing room and the water temperature increases the risk of heat shock. The second temperature measurement value T2 tends to reflect the outside air temperature, i.e., the temperature in the bathroom or changing room. The heat shock risk assessment function 62B compares the minimum value of the second temperature measurement value T2 for a certain period of time immediately before bathing detection, for example, between one and 20 minutes, with the maximum value for a certain period of time immediately after bathing detection, for example, between one and 5 minutes, and determines the risk of heat shock based on the comparison results. For example, if the difference between the two values ​​is greater than a predetermined threshold, it may be determined that the risk of heat shock is high.

[0092] If there is a large fluctuation in the second temperature measurement value T2 for a certain period of time immediately before and after the detection of hot water entry, a moving average process may be performed on the second temperature measurement value T2, and the degree of risk of heat shock may be evaluated based on the difference in the average values.

[0093] Fig. 11 is a flowchart showing the procedure for implementing the heat shock risk assessment function 62B. The procedure shown in Fig. 11 is executed, for example, when bathing is detected in step SA2 of Fig. 9 or step SB2 of Fig. 10. When bathing is detected, the processing unit 51 compares the second temperature measurement value T2 before bathing with the second temperature measurement value T2 after bathing (step SE1). Then, it determines whether the difference between the two values ​​is equal to or greater than a threshold (step SE2).

[0094] If the difference is equal to or greater than the threshold, the risk of heat shock is determined to be high (step SE3), and if the difference is less than the threshold, the risk of heat shock is determined to be low (step SE4).Then, the result of the heat shock risk determination is displayed on the display 52 (FIG. 1) (step SE5).

[0095] The heat shock risk assessment result displayed on the display 52 motivates the wearer of the ring device 10 to try to reduce the heat shock risk.

[0096] <Bathing Frequency Calculation Function> Next, the bathing frequency calculation function 62C (FIG. 1) will be described. The processing unit 51 executes a program that realizes the bathing frequency calculation function 62C to determine the number of days on which bathing was detected by the bathing detection function 61 during a predetermined determination period, and calculates the bathing frequency.

[0097] The bathing frequency calculation function 62C determines whether bathing has been detected for each day, counts the number of days on which bathing occurred over a certain period, such as a week or a month, and displays the counting results on the display 52. ​​For example, people who bathe almost every day are believed to be less likely to develop coronary artery disease or stroke than people who bathe less than twice a week. In other words, making bathing a habit reduces the risk of coronary artery disease and stroke.

[0098] Informing the wearer of the results of counting the number of days they have taken a bath over a certain period of time can be an opportunity to make bathing a habit.

[0099] <Bathing Effect Evaluation Function> Next, the bathing effect evaluation function 62D will be described. The processing unit 51 calculates an index for estimating the effect of bathing by executing a program that realizes the bathing effect evaluation function 62D. For example, after bathing detection function 61 detects bathing, the processing unit 51 continues at least one of measuring the temperature using the first temperature sensor 11, calculating the pulse rate using the optical sensor measurement value, and calculating a peripheral blood circulation index based on the optical sensor measurement value. Thereafter, an index showing the effect of bathing is calculated based on the time change of at least one of the measured temperature, calculated pulse rate, and calculated peripheral blood circulation index.

[0100] As an indicator of the effect of bathing, for example, the time until the first temperature measurement value T1, which reflects the temperature of the finger, returns to the value before bathing, or the time until the peripheral blood circulation index returns to the value before bathing, can be used. These indicator times reflect the time during which the heat retention effect of bathing is maintained. In other words, if the time for these indicators is long, it is estimated that bathing was effective.

[0101] For example, as shown in Figure 7A, if the pulse rate remains low and the peripheral blood circulation index remains high for a long period of time after exiting the bathtub, it can be assumed that bathing was effective. Because pulse rates vary from person to person, whether the pulse rate is high or low can be determined based on the pulse rate at rest before bathing, the average pulse rate over the past week, or the pulse rate while sleeping. Furthermore, because a person is not necessarily in a resting state before bathing or after exiting the bathtub, the average pulse rate over the past week while in a resting state while bathing can also be used as the basis.

[0102] When the average pulse rate over the past week while in a resting state while bathing is used as the standard, the effectiveness of bathing can be determined simply by the pulse rate. Generally, the pulse rate during sleep is lower than the pulse rate during bathing, and the peripheral blood circulation index during sleep is higher than the peripheral blood circulation index during bathing. Therefore, when the pulse rate during sleep is used as the standard, it is recommended to determine that bathing is effective if the pulse rate after getting out of the bathtub is 140% or less of the pulse rate during sleep. When the peripheral blood circulation index during sleep is used as the standard, it is recommended to determine that bathing is effective if the peripheral blood circulation index after getting out of the bathtub is 70% or more of the peripheral blood circulation index during sleep.

[0103] As shown in FIG. 8A, if the HF component of the pulse rate remains high, for example, above a predetermined threshold, after leaving the bathtub, it can be estimated that bathing was effective.

[0104] Figure 12 is a flowchart showing the procedure for implementing the hot water effect evaluation function 62D (Figure 1). The processing of steps SC1, SC2, and SC3 is the same as the processing of steps SB1, SB2, and SB3 shown in Figure 10. The optical sensor 13 continues to acquire photoplethysmographic information until a predetermined evaluation time has elapsed (step SC4). The processing of steps SC5, SC6, and SC7 after the predetermined evaluation time has elapsed is the same as the processing of steps SB6, SB7, and SB8 shown in Figure 10.

[0105] After outputting the result of the bathing suitability assessment, the system determines whether the user has left the bathtub (step SC8). This assessment is repeated at a predetermined interval until the user's exit is detected. When the user's exit is detected, the processing unit 51 continues to acquire photoplethysmographic information using the optical sensor 13 for a predetermined period (e.g., 30 minutes to 2 hours), and then executes the bathing effectiveness assessment function 62D program to assess the effectiveness of bathing (step SC9). In this case, it is preferable to set the frequency of intermittent measurements by the optical sensor 13 to the same frequency as the frequency of intermittent measurements during the bathing period.

[0106] The processing unit 51 then executes the input / output function 65 to output the evaluation result of the hot water bathing effect to the display 52 (FIG. 1) (step SC10). After outputting the evaluation result, the processing unit 51 stops the temperature measurement by the first temperature sensor 11 and the second temperature sensor 12 and the operation of the optical sensor 13 (step SC11).

[0107] Next, the advantages of the first embodiment will be described. In the first embodiment, the ring device 10 is worn on the finger, which reduces the resistance to bathing compared to when a wristwatch-type device is worn on the wrist. Furthermore, in the first embodiment, bathing is detected using both the first temperature measurement value T1 from the first temperature sensor 11, which tends to reflect the finger temperature, and the second temperature measurement value T2 from the second temperature sensor 12, which tends to reflect the outside air temperature. Therefore, the accuracy of bathing detection can be improved compared to a method that detects bathing based only on the water temperature measurement value after bathing.

[0108] To ensure that the finger temperature is more easily reflected in the first temperature measurement value T1 by the first temperature sensor 11, it is preferable to wear the first temperature sensor 11 so that the location where the sensor is placed is located on the pad side of the finger where there are many blood vessels. Conversely, to ensure that the finger temperature is less easily reflected in the second temperature measurement value T2 by the second temperature sensor 12, it is preferable to wear the second temperature sensor 12 so that the location where the sensor is placed is located on the dorsal side of the finger where there are fewer blood vessels.

[0109] To achieve this type of wearing, it is preferable to place the first temperature sensor 11 and the second temperature sensor 12 on opposite sides of the center of the ring device 10. Furthermore, it is preferable to decorate a portion of the outer circumferential surface of the ring device 10. It is preferable to determine the decoration location so that when the ring device 10 is worn with the decoration location located on the back of the finger, the first temperature sensor 11 is located on the pad side of the finger and the second temperature sensor 12 is located on the back of the finger.

[0110] In addition, in the first embodiment, as shown in Figures 9, 10, 12, etc., the optical sensor 13 (Figure 1) is activated after bathing is detected, and photoplethysmographic information acquisition begins. This reduces power consumption compared to when the optical sensor 13 is continuously activated regardless of whether or not the user is bathing. In particular, the finger-worn ring device 10 is smaller than wristwatch-type devices and therefore cannot be equipped with a large-capacity battery. The reduction in power consumption is a particularly significant effect for the finger-worn ring device 10.

[0111] Furthermore, in the first embodiment, the bathing evaluation function 62A can objectively evaluate whether bathing was appropriate. This encourages the wearer of the ring device 10 to bathe appropriately, for example, at an appropriate temperature. By bathing appropriately, the wearer can prevent excessive increases in blood pressure, pulse rate, arrhythmia, and the like.

[0112] Additionally, while the wearer is bathing, the notifier 16 (FIG. 1) of the ring device 10 notifies the wearer of the result of the determination of whether or not the bathing is appropriate. If the bathing is appropriate, the wearer can feel reassured that they are bathing appropriately. Conversely, if the bathing is inappropriate, the wearer can take corrective action. For example, they can adjust the water temperature or the bathing time.

[0113] Furthermore, in the first embodiment, the bathing effect evaluation function 62D (FIG. 1) allows the wearer of the ring device 10 to objectively know the effect of taking a bath.

[0114] In the first embodiment, as shown in FIG. 2B , a wiring board mounting multiple functional components includes rigid sections 21, 22, and 23, and flexible sections 24, 25, and 26. The first light-emitting element 13A and the light-receiving element 13C are mounted on the rigid section 22, and the second light-emitting element 13B is mounted on the rigid section 23. This reduces misalignment of these optical elements compared to a configuration in which they are mounted on flexible sections. As a result, photoplethysmographic information can be collected stably. Furthermore, by connecting the rigid sections with the flexible sections, the wiring board can be bent into a ring shape.

[0115] In order to stably fix the rigid portion 22 to the internal member 20, it is preferable that the rigid portion 22 be larger than the first opening 20A (FIG. 2A). Similarly, it is preferable that the rigid portion 23 be larger than the second opening 20B (FIG. 2A).

[0116] Next, a modification of the first embodiment will be described. In the first embodiment, as described with reference to FIG. 2C , the first temperature sensor 11 is located within the first arc-shaped region R1 in the circumferential direction, and the second temperature sensor 12 is located within the second arc-shaped region R2. In this modification, the circumferential positional relationship between the first temperature sensor 11 and the second temperature sensor 12 does not satisfy this relationship. For example, both the first temperature sensor 11 and the second temperature sensor 12 may be located within the first arc-shaped region R1 or within the second arc-shaped region R2.

[0117] Even with this arrangement, by mounting the first temperature sensor 11 on the surface facing the inner periphery of the rigid portion 23 and the second temperature sensor 12 on the surface facing the outer periphery of the rigid portion 21, the property that the temperature of the wearer's finger tends to be reflected in the first temperature measurement value by the first temperature sensor 11 and the outside temperature tends to be reflected in the second temperature measurement value by the second temperature sensor 12 is maintained. Note that the first temperature sensor 11 and the second temperature sensor 12 may be mounted on a common rigid portion.

[0118] In the first embodiment, one wiring board includes multiple rigid portions 21, 22, and 23 and multiple flexible portions 24, 25, and 26. However, multiple rigid wiring boards may be connected by wiring. In this case, the first temperature sensor 11 and the second temperature sensor 12 may be mounted on a common wiring board or on different wiring boards. That is, the hot water immersion determination device may include one or more wiring boards having an inner surface and an outer surface, with the first temperature sensor 11 located on the inner surface of one of the wiring boards and the second temperature sensor 12 located on the outer surface of one of the wiring boards.

[0119] Next, another variation of the first embodiment will be described with reference to FIG. 13. FIG. 13 is a block diagram showing the locations where the various functions of the hot water immersion determination device according to the variation of the first embodiment are realized. In the first embodiment (FIG. 1), programs that cause a computer to realize the various functions of the hot water immersion detection function 61 and the hot water immersion data processing function 62 are stored in the storage medium 60 of the control terminal 50, and these functions are realized by the control terminal 50. In contrast, in this variation, the storage medium 60 that stores the programs that realize these functions is distributed among the ring device 10, the control terminal 50, and the cloud 120. Data communication is performed between the control terminal 50 and the cloud 120 via a data communication network.

[0120] More specifically, the storage medium 60 of the bathing determination device is composed of a storage medium 60A of the ring device 10, a storage medium 60B of the control terminal 50, and a storage medium 60C of the cloud 120. A program that causes a computer to implement the bathing detection function 61 is stored in the storage medium 60A of the ring device 10. In this case, the functions of determining whether or not a bath has occurred in step SA2 (FIG. 9) and step SB2 (FIG. 10), and the function of determining whether or not a bath has been taken in step SB4 (FIG. 10) are implemented in the ring device 10.

[0121] A program for causing a computer to implement the input / output function 65 and the second communication function 66 is stored in the storage medium 60B of the control terminal 50. A program for causing a computer to implement the bathing data processing function 62, i.e., the bathing evaluation function 62A, the heat shock risk evaluation function 62B, the bathing frequency calculation function 62C, and the bathing effect evaluation function 62D, is stored in the storage medium 60C of the cloud 120.

[0122] Various data required when the cloud 120 executes the bathing data processing function 62 is sent from the ring device 10 to the cloud 120 via the control terminal 50. Evaluation results and processing results obtained by the cloud 120 executing the bathing data processing function 62 are sent from the cloud 120 to the control terminal 50. The control terminal 50 executes the input / output function 65 to output the evaluation results and processing results to the display 52.

[0123] A part of the information on the evaluation results and processing results may be transmitted from the control terminal 50 to the ring device 10, and the notifier 16 of the ring device 10 may be operated to notify the wearer of the ring device 10.

[0124] Next, other variations of the first embodiment will be described. In the first embodiment, as shown in FIG. 1, the bathing detection function 61 and the bathing data processing function 62 are implemented by the control terminal 50. In the variation of the first embodiment shown in FIG. 13, the bathing detection function 61 is implemented by the ring device 10, and the bathing data processing function 62 is implemented by the cloud 120. However, the locations where these functions are implemented are not limited to the first embodiment or the variation shown in FIG. 13. For example, these functions may be implemented by the ring device 10. In this case, programs that cause a computer to implement the bathing detection function 61 and the bathing data processing function 62 are stored in the storage medium 60A (FIG. 13) of the ring device 10. These programs are executed by the computer of the control unit 14. Furthermore, some functions of the bathing data processing function 62 may be implemented by the control terminal 50, and other functions may be implemented by the cloud 120.

[0125] In the first embodiment, a photoplethysmographic sensor that measures photoplethysmographic pulse waves is used as the optical sensor 13 (FIG. 1), but other optical sensors that acquire biological information may also be installed. For example, an oxygen saturation sensor or a laser Doppler blood flow sensor may also be installed. Light-emitting diodes (LEDs) are used as light-emitting elements for the photoplethysmographic sensor and the oxygen saturation sensor, and a vertical-cavity surface-emitting laser (VCSEL) is used as the light-emitting element for the laser Doppler blood flow sensor.

[0126] In the first embodiment, the ring device 10 is equipped with a first temperature sensor 11, a second temperature sensor 12, and an optical sensor 13 as sensors, but it may also be equipped with other sensors such as a piezoelectric sensor, a blood pressure sensor, a blood glucose sensor, an electrocardiogram sensor, and an electromyogram sensor.

[0127] Second Embodiment Next, a description will be given of a hot water immersion determination device according to a second embodiment. Below, a description of the components common to the hot water immersion determination device according to the first embodiment described with reference to Figures 1 to 12 will be omitted.

[0128] In the first embodiment, the photoelectric pulse wave information measured by operating the optical sensor 13 in step SA3 (FIG. 9) is transmitted in real time to the control terminal 50 (FIG. 1). In the second embodiment, the ring device 10 has a function of temporarily storing the photoelectric pulse wave information measured by operating the optical sensor 13 in the memory 15 (FIG. 1).

[0129] When the wearer of the ring device 10 is taking a bath, radio wave attenuation increases, which may cause unstable wireless communication between the ring device 10 and the control terminal 50. When wireless communication is unstable, the control unit 14 of the ring device 10 stores the photoelectric pulse wave information acquired by operating the optical sensor 13 in the memory 15. After the communication state improves, the control unit 14 reads the photoelectric pulse wave information from the memory 15 and transmits it to the control terminal 50.

[0130] Since it is necessary to perform the hot water entry detection in step SA2 (Figure 9) even when wireless communication is unstable, it is advisable to store a program that realizes the hot water entry detection function 61 (Figure 1) in the storage medium of the ring device 10 so that the control unit 14 of the ring device 10 can execute it.

[0131] Next, a description will be given of the advantageous effects of Example 2. In Example 2, photoplethysmographic information can be transmitted to the control terminal 50 even when wireless communication between the ring device 10 and the control terminal 50 is unstable.

[0132] [Third Example] Next, a hot water entry determination device according to a third example will be described with reference to Figures 14 and 15. Below, a description of the components common to the hot water entry determination device according to the first example described with reference to Figures 1 to 12 will be omitted.

[0133] 14 is a block diagram of the ring device 10 of the hot water use determination device according to the third embodiment. In addition to the components of the ring device 10 of the hot water use determination device according to the first embodiment, the ring device 10 of the hot water use determination device according to the third embodiment has a room entry detector 27. The room entry detector 27 detects that the wearer of the ring device 10 has entered an antechamber, such as a changing room, through which the wearer passes before entering the bathroom.

[0134] For example, a beacon receiver is installed in a changing room, and the entry detector 27 transmits a BLE beacon signal. When the beacon receiver receives the beacon signal transmitted from the ring device 10, it transmits an entry detection signal to the control terminal 50. Upon receiving the entry detection signal, the control terminal 50 notifies the ring device 10 that entry has been detected.

[0135] Alternatively, wireless communication via NFC may be used. For example, the ring device 10 may incorporate an NFC IC chip, an NFC reader may be attached near the door of the changing room, and the door may be unlocked by bringing the ring device 10 close to the NFC reader. Once the door is unlocked, the NFC reader notifies the ring device 10 that entry has been detected. When leaving the changing room, wireless communication via NFC is not required. By adopting this method, the ring device 10 can be notified of entry even if the control terminal 50 (FIG. 1) is not nearby.

[0136] When entry into the changing room is detected, the ring device 10 increases the sampling rate of temperature measurements by the first temperature sensor 11 and the second temperature sensor 12. For example, before entry is detected, the temperature measurement interval is set to 10 seconds or more and 1 minute or less, and after entry is detected, the temperature measurement interval is set to 0.1 seconds or more and 10 seconds or less. The subsequent procedure is the same as the procedure shown in FIG. 9, FIG. 10, or FIG. 12.

[0137] Next, the advantageous effects of the third embodiment will be described. If the ring device 10 does not have an entry detector 27 (FIG. 14), the sampling rate of the temperature measurements by the first temperature sensor 11 and the second temperature sensor 12 must be set to a certain level in order to detect hot water entry. For example, the temperature measurement interval must be set to 0.1 seconds or more and 10 seconds or less. In contrast, in the third embodiment, the sampling rate is set lower before entry detection than after entry detection. This makes it possible to suppress power consumption and reduce the amount of data on the temperature measurements by the first temperature sensor 11 and the second temperature sensor 12.

[0138] Next, the heat shock risk assessment function 62B (FIG. 1) realized by the hot water immersion determination device according to the third embodiment will be described.

[0139] 15 is a flowchart showing the procedure for the third embodiment of the hot water intake determination device to implement the heat shock risk assessment function 62B. First, temperature measurement is initiated using the first temperature sensor 11 and the second temperature sensor 12 (step SF1). The sampling rate of the temperature measurement at this time is lower than the sampling rate initiated in step SA1 (FIG. 9) of the first embodiment.

[0140] The control unit 14 of the ring device 10 determines whether entry into the changing room has been detected (step SF2). If entry is not detected, the first temperature sensor 11 and the second temperature sensor 12 continue to measure the temperature at the low sampling rate. If entry into the bath is detected, the control unit 14 increases the sampling rate of the temperature measurement by the first temperature sensor 11 and the second temperature sensor 12 (step SF3).

[0141] Then, the hot water entry detection process is initiated (step SF4). This determination process is repeated at a predetermined interval until hot water entry is detected. When hot water entry is detected, the second temperature measurement values ​​T2 before and after entry are compared with the second temperature measurement values ​​T2 after entry (step SF5). In step SE1 (FIG. 11) of the first embodiment, the second temperature measurement values ​​T2 before and after entry are compared, but in the third embodiment, the second temperature measurement values ​​T2 before and after entry are compared.

[0142] It is determined whether the difference is equal to or greater than a predetermined threshold (step SF6). This determination process and the subsequent steps SF7, SF8, and SF9 are the same as the steps SE3, SE4, and SE5 in FIG.

[0143] Next, we will explain the excellent effects of the heat shock risk assessment function 62B realized by the hot water entry determination device according to the third embodiment. The time between entering the dressing room and entering the bath is not constant and varies from person to person. For example, some people enter the bathroom after washing their hands and body before entering the bath, while others enter the bath immediately. If a person enters the bathroom after washing their hands and body before entering the bath, the second temperature measurement value T2 before entering the bath is affected by the outside air temperature and water temperature at the time of washing. As a result, the second temperature measurement value T2 before entering the bath may not accurately reflect the outside air temperature of the dressing room, etc.

[0144] In the third embodiment, the second temperature measurement value T2 before and after the time when entry into the changing room or the like is detected is used for comparison. Therefore, the second temperature measurement value T2 reflects the temperature of the changing room or the like, allowing for accurate evaluation of the risk of heat shock.

[0145] For example, in step SF5, the minimum value of the second temperature measurement T2 for each of the five minutes before and after the entry detection is compared with the maximum value of the second temperature measurement T2 for a predetermined evaluation time from the entry detection. The predetermined evaluation time may be, for example, between one minute and five minutes. If the second temperature measurement T2 fluctuates significantly, the minimum and maximum values ​​may be calculated based on the second temperature measurement T2 after performing a moving average process.

[0146] [Fourth Example] Next, a hot water immersion determination device according to a fourth example will be described with reference to Figures 16A and 16B. Below, a description of the components common to the hot water immersion determination device according to the first example described with reference to Figures 1 to 12 will be omitted. In the fourth example, as in the first example, the wearing of the ring device 10 (Figure 2C) is determined to be immersed in hot water.

[0147] 16A is a graph showing the actual measured values ​​of the first temperature measurement value T1 measured by the first temperature sensor 11 and the second temperature measurement value T2 measured by the second temperature sensor 12 over time when the ring device 10 is worn on a finger and immersed in hot water at a temperature of 40° C. Fig. 16B is a graph showing the actual measured values ​​of the first temperature measurement value T1 and the second temperature measurement value T2 over time when the water temperature is set to 43° C.

[0148] The horizontal axis of the graphs in Figures 16A and 16B represents the elapsed time (in seconds) from the point at which the rate of temperature change of the second measured temperature value T2 reaches its maximum, and the vertical axis represents the temperature (in degrees Celsius). The circle symbols and triangle symbols in the graphs in Figures 16A and 16B represent the actual measured values ​​of the first measured temperature value T1 and the second measured temperature value T2, respectively. The solid line and dashed line in the graphs in Figures 16A and 16B represent approximate curves obtained by approximating the changes over time of the first measured temperature value T1 and the second measured temperature value T2, respectively, using a logarithmic function.

[0149] Since body temperature is generally higher than the outside air temperature, before entering the bath, the first measured temperature T1 is higher than the second measured temperature T2. Furthermore, since the temperature of hot water is generally higher than body temperature, when the wearer of the ring device 10 enters the bath, the first measured temperature T1 and the second measured temperature T2 begin to rise. After entering the bath, the second measured temperature T2 rises due to the influence of the temperature of the hot water that comes into contact with the outer peripheral surface of the ring device 10.

[0150] Since the fingers are in contact with the inner peripheral surface of the ring device 10, hot water is unlikely to come into contact with the fingers. If there is a gap between the inner peripheral surface of the ring device 10 and the fingers, hot water will seep into this gap, but the amount of hot water that seeps in is very small. Therefore, the change in the first measured temperature value T1 due to the hot water temperature is slower than the change in the second measured temperature value T2. In the fourth embodiment, the first condition for determining whether to take a bath is that the temperature change rate of the second measured temperature value T2 exceeds a predetermined threshold.

[0151] 16A and 16B, it can be seen that as time passes after bathing, the second measured temperature T2 gradually approaches the first measured temperature T1 and then exceeds the first measured temperature T1. That is, the difference T2-T1 between the second measured temperature T2 and the first measured temperature T1 approaches zero from a negative value and then becomes positive. In the fourth embodiment, the second condition for bathing is that the difference T2-T1 between the second measured temperature T2 and the first measured temperature T1 exceeds a predetermined threshold.

[0152] As described above, in the bathing judgment device according to the fourth embodiment, the bathing detection function includes a function of determining that the wearer has taken a bath when the temperature change rate of the second temperature measurement value T2 exceeds a fourth threshold value (first condition) and the difference between the second temperature measurement value T2 and the first temperature measurement value T1 exceeds a fifth threshold value (second condition).

[0153] The fourth and fifth thresholds may be determined by conducting various evaluation experiments. For example, when the results shown in Figures 6A and 6B are obtained, 0.2°C / s is a possible fourth threshold. For example, when the results shown in Figure 16A are obtained, 0°C, -1°C, etc. are possible fifth thresholds. When 0°C is used as the fifth threshold, bathing is determined when approximately 25 seconds have elapsed. When -1°C is used as the fifth threshold, bathing is determined when approximately 8 seconds have elapsed. These fourth and fifth threshold values ​​can accurately determine bathing even when the water temperature is 43°C, as shown in Figure 16B.

[0154] Next, the advantages of the fourth embodiment will be described. As in the first embodiment, the fourth embodiment detects bathing using both the first temperature measurement value T1 from the first temperature sensor 11, which tends to reflect the finger temperature, and the second temperature measurement value T2 from the second temperature sensor 12, which tends to reflect the outside air temperature. This improves the accuracy of bathing detection compared to a method that detects bathing based only on the water temperature measurement after bathing.

[0155] Next, a modification of the fourth embodiment will be described. In this modification, in addition to the first condition, a third condition for determining that the wearer has taken a bath is adopted, that is, that the change over time in the second measured temperature value T2 can be approximated by a logarithmic function. In this modification, if the first and third conditions are satisfied, it is determined that the wearer has taken a bath.

[0156] In the example shown in FIG. 16A, when the elapsed time is denoted as t, the change in the second temperature measurement value T2 over time is approximated by the following equation when the elapsed time is between 5 seconds and 40 seconds. In this approximation formula, the coefficient of determination R ２ is 0.998.

[0157] In the example shown in FIG. 16B, the change over time of the second measured temperature value T2 is approximated by the following equation when the elapsed time is between 5 seconds and 40 seconds. In this approximation formula, the coefficient of determination R ２ is 0.995.

[0158] For example, when the change over time of the second temperature measurement value T2 is expressed as a logarithmic function, the coefficient of determination R ２ is equal to or greater than the judgment threshold, it is determined that the time change of the second temperature measurement value T2 can be logarithmically approximated. To increase the detection sensitivity, it is preferable to lower the judgment threshold. Conversely, to suppress false detection, it is preferable to raise the judgment threshold. The judgment threshold should be set according to the required detection sensitivity, the allowable false detection, etc. As an example, when high detection sensitivity is required, it is preferable to set the judgment threshold to 0.7. Furthermore, when there is a strong demand for suppressing false detection, it is preferable to set the judgment threshold to 0.9.

[0159] Next, the advantageous effects of this modification will be described. For example, when the wearer of the ring device 10 takes a shower, the second measured temperature value T2 rises when hot water from the shower comes into contact with the ring device 10. However, because the hot water from the shower does not always come into contact with the ring device 10, the change in the second measured temperature value T2 over time cannot be approximated by a logarithmic function. This modification makes it less likely that a situation will occur in which the wearer of the ring device 10 taking a shower is mistakenly detected as taking a bath.

[0160] Next, the period (hereinafter referred to as the determination period) that is the target for determining whether approximation by a logarithmic function is possible will be described. The point in time when the temperature change rate of the second temperature measurement value T2 reaches a maximum corresponds to an inflection point in the time change of the second temperature measurement value T2. Because the accuracy of approximation decreases near the inflection point, it is preferable to exclude from the determination period the period around the point in time when the temperature change rate of the second temperature measurement value T2 reaches a maximum. As an example, it is preferable to exclude from the determination period a certain period (e.g., 5 seconds) that begins from the point in time when the temperature change rate of the second temperature measurement value T2 reaches a maximum.

[0161] Furthermore, if the target period for judgment is set too long, the time between actually entering the bath and the bathing judgment will be too long. Conversely, if the target period for judgment is too short, the accuracy of the judgment will decrease. As an example, the target period for judgment can be set to the period from the point at which the temperature change rate of the second temperature measurement value T2 reaches its maximum until a certain time (e.g., 40 seconds) has elapsed. In other words, the target period for judgment can be set to the point at which 5 seconds have elapsed since the point at which the temperature change rate of the second temperature measurement value T2 reaches its maximum until 10 to 40 seconds have elapsed.

[0162] It may be determined that the wearer has taken a bath if all three of the first, second, and third conditions are satisfied. By adopting these three conditions as bathing judgment conditions, the accuracy of the determination can be improved.

[0163] [Fifth Example] Next, a hot water entry determination device according to a fifth example will be described with reference to Figures 17A and 17B. Below, a description of the components common to the hot water entry determination device according to the first example described with reference to Figures 1 to 12 will be omitted. Similarly to the first example, the fifth example also uses the ring device 10 (Figure 2C). In the fifth example, it is determined whether the wearer of the ring device 10 has left the bathtub.

[0164] 17A is a graph showing the actual measured values ​​of the change over time of the first temperature measurement value T1 measured by the first temperature sensor 11 and the second temperature measurement value T2 measured by the second temperature sensor 12 when the ring device 10 is worn on a finger and the user exits hot water at a temperature of 40° C. FIG. 17B is a graph showing the actual measured values ​​of the change over time of the first temperature measurement value T1 and the second temperature measurement value T2 when the water temperature is set to 43° C.

[0165] The horizontal axis of the graphs in Figures 17A and 17B represents the elapsed time (in seconds) until the temperature change rate of the second temperature measurement value T2 reaches a minimum, and the vertical axis represents temperature (in degrees Celsius). Because the temperature change rate of the second temperature measurement value T2 is negative, the temperature change rate of the second temperature measurement value T2 reaching a minimum corresponds to the absolute value of the temperature change rate of the second temperature measurement value T2 reaching a maximum. The point in time when the temperature change rate of the second temperature measurement value T2 reaches a minimum is set as the reference time of elapsed time, and the length of time going back from this reference time is represented by a negative value. The circles and triangles in the graphs in Figures 17A and 17B represent the actual measured values ​​of the first temperature measurement value T1 and the second temperature measurement value T2, respectively. The solid and dashed lines in the graphs in Figures 17A and 17B represent approximate curves obtained by approximating the time changes of the first temperature measurement value T1 and the second temperature measurement value T2, respectively, using a logarithmic function.

[0166] When the wearer leaves the bathtub, the first temperature measurement value T1 and the second temperature measurement value T2 begin to decrease. As shown in Figures 6A and 6B, when the wearer leaves the bathtub, the temperature change rate of the second temperature measurement value T2 reaches a minimum. Therefore, one condition for determining that the wearer has left the bathtub is that the temperature change rate of the second temperature measurement value T2 falls below a predetermined threshold.

[0167] 17A and 17B, the change over time of the second measured temperature value T2 can be approximated by a logarithmic function. Therefore, the ability to logarithmically approximate the change over time of the second measured temperature value T2 is adopted as another condition for determining that the wearer has left the bathtub.

[0168] As described above, in the bathing detection device according to the fifth embodiment, the bathing detection function includes a function to detect that the wearer has left the bathtub when it is determined that the rate of temperature change of the second temperature measurement value T2 (the second temperature measurement value T2 is decreasing, so the rate of temperature change is a negative value) falls below the sixth threshold value and that the change over time of the second temperature measurement value T2 can be approximated by a logarithmic function.

[0169] The sixth threshold may be determined by carrying out various evaluation experiments. For example, when the results shown in Figures 6A and 6B are obtained, -0.1°C / s may be selected as a candidate for the sixth threshold.

[0170] In the example shown in FIG. 17A, if the elapsed time is denoted as t, the change over time of the second measured temperature value T2 when the elapsed time is between −20 seconds and −5 seconds is approximated by the following equation. In this approximation formula, the coefficient of determination R ２ is 0.920.

[0171] In the example shown in FIG. 17B, the change in the second temperature measurement value T2 over time when the elapsed time is between −20 seconds and −5 seconds is approximated by the following equation. In this approximation formula, the coefficient of determination R ２ is 0.921.

[0172] For example, when the change over time of the second temperature measurement value T2 is expressed as a logarithmic function, the coefficient of determination R ２ is equal to or greater than the judgment threshold, it is determined that the time change of the second measured temperature value T2 can be logarithmically approximated. This judgment threshold should be lowered to increase the detection sensitivity. Conversely, to avoid false detection, it is preferable to increase the judgment threshold. The judgment threshold should be set according to the required detection sensitivity, the allowable false detection, etc. As an example, when high detection sensitivity is required, the judgment threshold should be set to 0.7. Furthermore, when there is a strong need to avoid false detection, the judgment threshold should be set to 0.9.

[0173] Next, a period (hereinafter referred to as the determination period) that is the target for determining whether approximation by a logarithmic function is possible will be described. The point in time when the rate of temperature change of the second temperature measurement value T2 becomes minimum corresponds to an inflection point in the time change of the second temperature measurement value T2. Because the accuracy of approximation decreases near the inflection point, it is preferable to exclude from the determination period the period near the point in time when the rate of temperature change of the second temperature measurement value T2 becomes minimum. As an example, it is preferable to exclude from the determination period a period going back a certain time (e.g., 5 seconds) from the point in time when the rate of temperature change of the second temperature measurement value T2 becomes minimum.

[0174] Furthermore, if the target period for determination is set too long, the second temperature measurement value T2 must be stored for a long period of time. Conversely, if the target period for determination is set too short, the accuracy of the determination will decrease. As an example, the target period for determination may include a period extending back a certain time (e.g., 20 seconds) from the point at which the rate of temperature change of the second temperature measurement value T2 becomes minimum. In other words, the target period for determination may be set from -20 seconds to -5 seconds from the point at which the rate of temperature change of the second temperature measurement value T2 becomes minimum.

[0175] Next, the advantages of the fifth embodiment will be described. In the fifth embodiment, the condition for determining whether a person has left the bathtub is not only the rate of change of the second measured temperature value T2, but also whether the change in the second measured temperature value T2 over time can be approximated by a logarithmic function. This reduces the likelihood of false detection of a person leaving the bathtub.

[0176] The above-described embodiments are merely examples, and it goes without saying that partial substitution or combination of the configurations shown in different embodiments is possible. Similar effects resulting from similar configurations of multiple embodiments will not be mentioned sequentially for each embodiment. Furthermore, the present invention is not limited to the above-described embodiments. For example, it will be obvious to those skilled in the art that various modifications, improvements, combinations, etc. are possible.

[0177] 10 Ring device 11 First temperature sensor 12 Second temperature sensor 13 Optical sensor 13A First light-emitting element 13B Second light-emitting element 13C Light-receiving element 14 Control unit 15 Memory 16 Notifier 17 Battery 18 First communication unit 19 Acceleration gyro sensor 20 Internal member 20A First opening 20B Second opening 21, 22, 23 Rigid portion 24, 25, 26 Flexible portion 27 Room entry detector 30 Transparent resin member 30A, 30B Protruding portion 31 Outer member 50 Control terminal 51 Processing unit 52 Display 53 Sound generator 54 Vibration generator 55 Second communication unit 60 Storage medium 60A Ring device storage medium 60B Control terminal storage medium 60C Cloud storage medium 61 Bath entry detection function 62 Bathing data processing function 62A Bathing evaluation function 62B Heat shock risk evaluation function 62C Bathing frequency calculation function 62D Bathing effect evaluation function 65 Input / output function 66 Second communication function 100 Server 110 Storage medium 120 Cloud

Claims

1. A bathing determination device comprising: a ring device configured to be worn on a finger; and a storage medium, wherein the ring device comprises: a first temperature sensor; a second temperature sensor; an optical sensor that emits light toward the finger on which the ring device is worn and receives diffusely reflected light from the finger; a control unit that controls the first temperature sensor, the second temperature sensor, and the optical sensor; and one or more wiring boards having a surface facing an inner circumference and a surface facing an outer circumference, wherein the first temperature sensor is arranged on the surface facing the inner circumference of one of the wiring boards, and the second temperature sensor is arranged on the surface facing the outer circumference of one of the wiring boards, and the storage medium stores a program that causes a computer to realize: a bathing detection function that detects that the wearer of the ring device has taken a bath based on a first temperature measurement value measured by the first temperature sensor and a second temperature measurement value measured by the second temperature sensor; and a bathing data processing function that processes data based on the optical sensor measurement value measured by the optical sensor when the bathing detection function detects that the wearer has taken a bath.

2. A hot water intake determination device as described in claim 1, wherein when the inner surface of the ring device is divided circumferentially into two regions, a first arc-shaped region and a second arc-shaped region, each having the same circumferential length, and the distribution range of the optical sensor is positioned at the center of the first arc-shaped region in the circumferential direction, the first temperature sensor is positioned within the range of the first arc-shaped region and the second temperature sensor is positioned within the range of the second arc-shaped region in the circumferential direction.

3. A bathing judgment device as described in claim 1 or 2, wherein the bathing data processing function includes a bathing evaluation function that calculates the pulse rate based on the optical sensor measurement value and determines whether the bathing was appropriate or not based on the calculated pulse rate.

4. A bathing judgment device as described in any one of claims 1 to 3, wherein the bathing data processing function further includes a function of calculating a peripheral blood circulation index that reflects the blood circulation of the peripheral blood vessels based on the optical sensor measurement value, and determining whether the bathing was appropriate or not based on the calculated value of the peripheral blood circulation index.

5. The bathing judgment device of claim 1 or 2, wherein the bathing data processing function further includes a bathing effect evaluation function that, after bathing is detected by the bathing detection function, continues at least one of measuring the temperature using the first temperature sensor, calculating the pulse rate using the optical sensor measurement value, and calculating a peripheral blood circulation index reflecting the blood circulation in the peripheral blood vessels based on the optical sensor measurement value, and calculates an index showing the effect of bathing based on the time change of at least one of the measured temperature value, the calculated pulse rate, and the calculated value of the peripheral blood circulation index.

6. A bathing determination device as described in any one of claims 1 to 5, wherein the bathing data processing function further includes a bathing frequency calculation function that determines the number of days on which bathing is detected by the bathing detection function during a specified determination period and calculates the bathing frequency.

7. A hot water intake determination device as described in any one of claims 1 to 6, wherein the ring device further comprises a memory and a first communication unit, the storage medium further stores a program that causes a computer to realize a second communication function that communicates with the first communication unit, and the control unit stores the first temperature measurement value, the second temperature measurement value, and the optical sensor measurement value in the memory, and transmits the first temperature measurement value, the second temperature measurement value, and the optical sensor measurement value stored in the memory via the first communication unit to a computer that realizes the second communication function.

8. A bathing judgment device as described in any one of claims 1 to 7, wherein the ring device further includes a notifier for notifying the wearer of information, and the control unit notifies the wearer of information indicating the processing results of the bathing data processing function via the notifier.

9. The hot water entry determination device according to any one of claims 1 to 8, wherein the ring device further includes an entry detector that detects entry into an antechamber that is passed through before entering the bathroom, and after entry is detected by the entry detector, the hot water entry detection process is initiated by the hot water entry detection function.

10. A bathing detection device as described in any one of claims 1 to 9, wherein the bathing detection function includes a function of determining that the wearer has taken a bath when the rate of temperature change of both the first temperature measurement value and the second temperature measurement value exceeds a first threshold value.

11. A bathing detection device as described in any one of claims 1 to 8, wherein the bathing detection function includes a function to determine that the wearer has taken a bath if the temperature change rate of the second temperature measurement value is greater than the temperature change rate of the first temperature measurement value and the difference is equal to or greater than a second threshold value.

12. A bathing detection device as described in any one of claims 1 to 11, wherein the bathing detection function further includes a function to detect that the wearer has left the bathtub when the minimum value of the rate of change of the second temperature measurement value falls below a third threshold value.

13. The hot water entry determination device according to any one of claims 1 to 12, wherein the storage medium further stores a program that causes a computer to implement a heat shock risk assessment function that, when hot water entry is detected by the hot water entry detection function, compares the second temperature measurement value before entering the bath with the second temperature measurement value after entering the bath and determines the degree of risk of heat shock.

14. The hot water entry determination device of claim 9, wherein the storage medium further stores a program that causes a computer to realize a heat shock risk assessment function that, when entry into a bath is detected by the hot water entry detection function, compares the second temperature measurement values ​​before and after the entry into the bath is detected by the entry detector with the second temperature measurement values ​​after entry into the bath, and determines the degree of risk of heat shock.

15. A bathing detection device as described in any one of claims 1 to 9, wherein the bathing detection function includes a function of determining that the wearer has taken a bath when the rate of temperature change of the second temperature measurement value exceeds a fourth threshold value and the difference between the second temperature measurement value and the first temperature measurement value exceeds a fifth threshold value.

16. A bathing detection device as described in any one of claims 1 to 9, wherein the bathing detection function includes a function for determining that the wearer has taken a bath when it is determined that the rate of temperature change of the second temperature measurement value exceeds a fourth threshold value and that the change over time of the second temperature measurement value can be approximated by a logarithmic function.

17. A bathing detection device as described in any one of claims 1 to 11, wherein the bathing detection function further includes a function to detect that the wearer has left the bathtub when it is determined that the rate of temperature change of the second temperature measurement value falls below a sixth threshold and that the change over time of the second temperature measurement value can be approximated by a logarithmic function.

Images