Pressure sensor and wearable sensor

Abstract

To provide a technology which can give off a sensor signal in which only the pressure to be truly detected is accurately reflected in a glove-type wearable sensor in which a film-like pressure sensor is assembled into a fingertip of a thin work glove.SOLUTION: A film-like pressure sensor is assembled into the fingertip of a glove-type wearable sensor and made by laminating in a vertical direction at least one or more flexible substrates and one sheet-like pressure-sensitive element one on top of another with the vertical direction, a pressure sensor longitudinal direction, and a pressure sensor lateral direction regarded as three coordinate axial directions in a three-dimensional orthogonal coordinate system, respectively. The film-like pressure sensor detects only the pressure applied to the fingertip of a wearer after the wearable sensor is worn.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a pressure sensor and a glove-type wearable sensor in which the pressure sensor is incorporated into the fingertips. [Background technology]

[0002] Even in today's manufacturing industry where production lines are becoming increasingly automated, there are still many work processes that require human labor. These work processes that require human labor face challenges such as a chronic labor shortage due to the decline in the working-age population, as well as the retirement of skilled workers and the resulting lack of successors. As part of efforts to solve these challenges, in recent years, digital data has been created of the movements of skilled workers while they are working, and this data is used as teaching materials in vocational training to develop successors, and as a standard for checking whether work is accurate or not.

[0003] One of the main methods for digitalizing the movements of people working is to have the worker wear various wearable sensors and directly sense the movements of the worker. For example, when digitalizing various manual tasks including the movements of grasping and releasing objects, a method that utilizes a glove-type wearable sensor in which a film- or sheet-type pressure sensor is embedded in the fingertips of a work glove is known as an effective method (e.g., Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-001410 Summary of the Invention [Problem to be solved by the invention]

[0005] In actual manufacturing sites, it is extremely important that glove-type wearable sensors worn by workers have a comfortable fit that fits well around the hands and does not impede work. Therefore, glove-type wearable sensors for such purposes are preferably ones in which a film- or sheet-type (hereinafter simply referred to as "film-type") pressure sensor is built into the fingertips of thin work gloves.

[0006] However, if such a wearable sensor is made using thin work gloves in order to obtain a comfortable fit, there is a problem in that when the wearable sensor is put on or when the finger is bent after putting it on, various stresses act on the pressure-sensitive element inside the pressure sensor, causing the pressure sensor to react and obtain unnecessary sensor values.

[0007] In view of the above problems, the present invention aims to provide a technology for a glove-type wearable sensor in which a film-shaped pressure sensor is incorporated into the fingertips of a thin work glove, capable of emitting a sensor signal that accurately reflects only the pressure that is truly to be detected. [Means for solving the problem]

[0008] The pressure sensor according to the present invention is a film-like pressure sensor incorporated into the fingertips of a glove-type wearable sensor, and is composed of at least one flexible substrate and one sheet-like pressure-sensitive element stacked in the vertical direction, with the three coordinate axis directions in a three-dimensional orthogonal coordinate system being the vertical direction, the longitudinal direction of the pressure sensor, and the width direction of the pressure sensor, and detects only the pressure applied to the wearer's fingertips after the wearable sensor is worn.

[0009] Further, a glove-type wearable sensor in which the above-mentioned pressure sensor is incorporated in the fingertips is also within the scope of the present invention.

[0010] In addition, the problems and solutions disclosed in this application will be made clear by the description of the preferred embodiment and the drawings. Effect of the Invention

[0011] According to the present invention, a glove-type wearable sensor having a film-type pressure sensor built into the fingertips of a thin work glove can accurately detect only the pressure applied to the fingertips of a wearer after the wearable sensor is worn. As a result, it becomes possible to emit a sensor signal that accurately reflects only the pressure that is truly to be detected. [Brief description of the drawings]

[0012] [Figure 1] The external appearance of the wearable sensor is shown. [Diagram 2] 1 shows a configuration of a pressure sensor according to a first embodiment. [Figure 3A] 4 shows a modified example of the configuration of the pressure sensor in accordance with the first embodiment. [Figure 3B] 4 shows a modified example of the configuration of the pressure sensor in accordance with the first embodiment. [Figure 4A] 1 shows a configuration of a pressure sensor according to a second embodiment. [Figure 4B] 1 shows a configuration of a pressure sensor according to a second embodiment. [Diagram 5] 11 shows a modified example of the configuration of the flexible substrate of the pressure sensor in accordance with the second embodiment. [Figure 6] 11 shows a modified example of the configuration of the flexible substrate of the pressure sensor in accordance with the second embodiment. [Figure 7] 1 shows a configuration of a pressure sensor according to a third embodiment. [Figure 8A] 11 shows a configuration of an upper substrate of a pressure sensor in accordance with Example 3. [Figure 8B] 11 shows the configuration of a lower substrate of a pressure sensor according to Example 3. [Figure 9A] 13 shows a modified example of the configuration of the upper substrate of the pressure sensor in accordance with the third embodiment. [Figure 9B] 13 shows a modified example of the configuration of the lower substrate of the pressure sensor according to the third embodiment. [Figure 10] 10 shows the relationship between the electrode terminals used and the acquired sensor signal in the pressure sensor using the flexible substrate shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Several examples will be described below.

[0014] In the following description, it is assumed that the three coordinate axis directions in the three-dimensional orthogonal coordinate system are the up-down direction, the longitudinal direction of the pressure sensor, and the width direction of the pressure sensor. EXAMPLES

[0015] First, an overview of the wearable sensor will be given.

[0016] FIG. 1 shows the appearance of a wearable sensor 1.

[0017] As shown in FIG. 1, the wearable sensor 1 is a glove-type wearable sensor in which a film-like pressure sensor 11 is incorporated into the fingertips of a thin work glove, also called a sensor glove or a sensor-embedded glove. The pressure sensor 11 is incorporated in an area centered on the pad side of the fingertips of the wearable sensor 1, and when the wearable sensor 1 is worn on the hand of a wearer, the shape of the wearer's fingertips is deformed to fit the shape of the wearer's fingertips. This allows the wearable sensor 1 to fit well on the wearer's hand. As a result, the wearer of the wearable sensor 1 can obtain a comfortable fit that does not interfere with work even in an actual manufacturing site.

[0018] Furthermore, in the wearable sensor 1, the pressure sensor 11 incorporated in the fingertip has the characteristics described below, and thus various stresses acting on the pressure-sensitive element of the pressure sensor 11 incorporated in the fingertip can be alleviated when the wearable sensor 1 is worn or when the finger is bent after wearing the wearable sensor 1. As a result, the wearable sensor 1 can appropriately detect only the pressure applied to the wearer's fingertip after wearing it (described in detail later).

[0019] That is, by virtue of having the above-mentioned characteristics, wearable sensor 1 fits well on the wearer's hand and can accurately detect only the pressure applied to the wearer's fingertip after wearing the sensor.

[0020] 1 is illustrated as having pressure sensor 11 incorporated in the tip of the index finger for ease of understanding, but pressure sensor 11 may of course be incorporated in the tips of other fingers or in the tips of multiple fingers. The specific position and orientation of pressure sensor 11 incorporated in the fingertip of wearable sensor 1 may be appropriately determined according to the content of the movement performed by the wearer during work and the physical characteristics of the wearer.

[0021] Next, the pressure sensor incorporated in the wearable sensor 1 will be described.

[0022] FIG. 2 shows the configuration of a pressure sensor 11a according to the first embodiment.

[0023] The pressure sensor 11a shown in FIG. 2 includes one flexible substrate 12a, one pressure-sensitive element 13, and one protective film 14. The flexible substrate 12a is a polymer thick film (PTF) having sheet-shaped electrodes made of conductive metal foil such as copper foil provided therein. The electrodes provided on the flexible substrate 12a are formed in a substantially comb shape when viewed from above and below. On the upper surface side of the flexible substrate 12a, a sheet-shaped pressure-sensitive element 13 is provided substantially parallel to the flexible substrate 12a. The pressure-sensitive element 13 is electrically connected to the electrodes of the flexible substrate 12a. A protective film 14 made of insulating resin is disposed on the upper surface side of the pressure-sensitive element 13, and the upper surface of the flexible substrate 12a and the lower surface of the protective film 14 are adhesively fixed to each other at the periphery of the pressure sensor 11a.

[0024] That is, the pressure-sensitive element 13 is enclosed in the internal space of the pressure sensor 11a formed by the upper surface of the flexible substrate 12a and the lower surface of the protective film 14, with its lower surface facing the upper surface of the flexible substrate 12a and its upper surface facing the lower surface of the protective film 14. Between the lower surface of the pressure-sensitive element 13 and the upper surface of the flexible substrate 12a, and between the upper surface of the pressure-sensitive element 13 and the lower surface of the protective film 14, films 15 that are non-adhesive on both sides are respectively interposed.

[0025] When various pressures are applied to the fingertip of the wearable sensor 1(1a) incorporating the pressure sensor 11a, the pressure sensor 11a deforms, and the pressure-sensitive element 13 inside the pressure sensor 11a also deforms accordingly. When the wearable sensor 1(1a) is not yet worn, i.e., in the initial state, conductive particles are present uniformly at approximately equal intervals inside the pressure-sensitive element 13. However, when the pressure-sensitive element 13 deforms, the distance between the particles present inside expands or contracts partially. Therefore, the electrical resistance value inside the pressure-sensitive element 13 changes when electricity is applied. This allows the wearable sensor 1(1a) to detect various pressures applied to the fingertip.

[0026] In addition, unlike the pressure sensor 11a, the pressure sensor of the prior art does not have a film 15 with double-sided non-adhesive between the lower surface of the pressure-sensitive element and the upper surface of the flexible substrate, and between the upper surface of the pressure-sensitive element and the lower surface of the protective film, and the lower surface of the pressure-sensitive element and the upper surface of the flexible substrate, and the upper surface of the pressure-sensitive element and the lower surface of the protective film are adhesively fixed to each other. Therefore, when the pressure sensor is deformed, due to the difference in the physical properties and mechanical characteristics of the flexible substrate, the pressure-sensitive element, and the protective film, in addition to (1) the stress acting on the pressure-sensitive element itself during deformation, (2) the stress applied from the protective film and (3) the stress applied from the flexible substrate act on the pressure-sensitive element. Therefore, the pressure detected by the pressure sensor of the prior art is any one of the above (1) to (3) or a combination of the above (1) to (3). Due to the existence of such problems, the pressure sensor of the prior art cannot emit a sensor signal that accurately reflects only the pressure that should truly be detected.

[0027] However, in the pressure sensor 11a, as described above, the double-sided non-adhesive film 15 is interposed between the lower surface of the pressure-sensitive element 13 and the upper surface of the flexible substrate 12a, and between the upper surface of the pressure-sensitive element 13 and the lower surface of the protective film 14. Therefore, the pressure-sensitive element 13 is disposed inside the pressure sensor 11a with its lower surface not adhesively fixed to the upper surface of the flexible substrate 12a, and its upper surface not adhesively fixed to the lower surface of the protective film 14. As a result, unnecessary stress acting on the pressure-sensitive element due to the relationship with the flexible substrate and the protective film in the prior art is not applied to the pressure-sensitive element 13, and the pressure sensor 11a can generate a sensor signal that accurately reflects only the pressure that is truly to be detected.

[0028] The pressure sensor may have its longitudinal side protected by an adhesive film divided into multiple pieces, as shown in Fig. 3. In this case, the side of pressure sensor 11b may be separately protected by adhesive film 16 divided into multiple pieces, as shown in Fig. 3A, or the side of protective film 14b protecting the side of pressure sensor 11b may be divided into multiple pieces, as shown in Fig. 3B. In this case, the side of adhesive film 16 or protective film 14b protecting the side of pressure sensor 11b is divided into multiple pieces, so that the stress applied to the side of pressure sensor 11b can be alleviated. EXAMPLES

[0029] The wearable sensor 1b of the second embodiment is the same as the wearable sensor 1 (1a) shown in FIG. 1 in the description of the first embodiment, except that the structure of the pressure sensor incorporated in the fingertip is different.

[0030] Fig. 4 shows the configuration of a pressure sensor 21 according to Example 2. Fig. 4A is a vertical cross-sectional view, and Fig. 4B is a top view.

[0031] The pressure sensor 21 shown in FIG. 4 includes one flexible substrate 12a, a plurality of sheet-like pressure-sensitive elements 23 divided into strips with the width direction of the pressure sensor 21 as the longitudinal direction, and one protective film 14. The pressure-sensitive elements 23 are sealed in the internal space of the pressure sensor 21 formed by the upper surface of the flexible substrate 12a and the lower surface of the protective film 14 with the lower surface facing the upper surface of the flexible substrate 12a and the upper surface facing the lower surface of the protective film 14. The pressure-sensitive elements 23 are arranged so as to be approximately parallel to other pressure-sensitive elements 23 arranged adjacent to each other, and a constant interval is provided between each pressure-sensitive element 23. In other words, the multiple strip-like pressure-sensitive elements 23 are arranged at approximately equal intervals so that the width direction of each is the longitudinal direction of the pressure sensor 21. As a result, the pressure sensor 21 bends at the intervals provided between the pressure-sensitive elements 23, so that the stress acting on each pressure-sensitive element 23 is only due to the pressure that is truly to be detected. As a result, the pressure sensor 21 can emit a sensor signal that accurately reflects only the pressure that is actually to be detected.

[0032] The electrodes of the flexible substrate used in the pressure sensor 21 may have a wiring pattern formed such that the positions at which the pressure-sensitive elements 23 are arranged overlap with the positions of the wires, as in the flexible substrate 12b shown in FIG. 5. In this case, the pressure sensor 21 can detect the stress acting on each pressure-sensitive element 23 with higher accuracy. In addition, in this case, the wires of the flexible substrate 12b are not arranged at the positions of the gaps between the pressure-sensitive elements 23, so that the pressure sensor 21 is more likely to bend at the positions of the gaps. Furthermore, in this case, when the pressure sensor 21 is manufactured, each pressure-sensitive element 23 can be easily arranged because it is sufficient to arrange each pressure-sensitive element 23 according to the wiring pattern of the flexible substrate 12b.

[0033] In addition, the flexible substrate used in the pressure sensor 21 may be formed to be easily bent by forming the position overlapping with the gap thinner than other positions or by forming the position from a material that is easier to bend, different from other positions, like the flexible substrate 12c shown in Fig. 6. In this case, the pressure sensor 21 can be made to bend more easily at the positions of the gaps provided between the pressure-sensitive elements 23. EXAMPLES

[0034] The wearable sensor 1c of the third embodiment is the same as the wearable sensor 1 (1a) shown in FIG. 1 in the description of the first embodiment, except that the structure of the pressure sensor incorporated in the fingertip is different.

[0035] FIG. 7 shows the configuration of a pressure sensor 31 according to the third embodiment.

[0036] 7 includes two different flexible substrates (32a, 32b) and one sheet-like pressure-sensitive element 33. The pressure-sensitive element 33 is equivalent to the pressure-sensitive element 13 of the first embodiment, and is enclosed in the internal space of the pressure sensor 31 formed by the upper surface of the upper flexible substrate 32a and the lower surface of the lower flexible substrate 32b, with the upper surface 51 facing the lower surface of the upper flexible substrate 32a and the lower surface 52 facing the upper surface of the lower flexible substrate 32b.

[0037] An upper surface 51 of the pressure-sensitive element 33 is adhesively fixed to the lower surface of the upper flexible substrate 32a. Therefore, a tensile stress acts on the upper surface 51 of the pressure-sensitive element 33 due to its relationship with the upper flexible substrate 32a.

[0038] Further, the lower surface 52 of the pressure-sensitive element 33 is adhesively fixed to the upper surface of the lower flexible substrate 32b. Therefore, a compressive stress acts on the lower surface 52 of the pressure-sensitive element 33 in relation to the lower flexible substrate 32b.

[0039] The upper flexible substrate 32a shown in FIG. 8A and the lower flexible substrate 32b shown in FIG. 8B are provided with only one of the positive and negative electrodes, unlike the flexible substrates (12a, 12b, 12c) of the first and second embodiments in which the electrodes 17 of both positive and negative polarities are provided. The upper flexible substrate 32a shown in FIG. 8A is provided with a positive electrode, and the lower flexible substrate 32b shown in FIG. 8B is provided with a negative electrode. Therefore, in the pressure sensor 31, a current flows from the lower flexible substrate 32b to the upper flexible substrate 32a through the pressure-sensitive element 33. As a result, the tensile stress acting on the upper surface 51 of the pressure-sensitive element 33 in relation to the upper flexible substrate 32a and the compressive stress acting on the lower surface 52 of the pressure-sensitive element 33 in relation to the lower flexible substrate 32b are offset, so that the pressure sensor 31 can eliminate the influence of these stresses. As a result, the pressure sensor 31 can emit a sensor signal that accurately reflects only the pressure that is truly to be detected.

[0040] 8A and 8B, the stripes of the electrodes of the upper flexible substrate 32a and the stripes of the electrodes of the lower flexible substrate 32b, each of which is arranged in a substantially striped pattern, may be oriented in different directions. By arranging the electrodes of the flexible substrates (32a, 32b) in a substantially striped pattern, the pressure sensor 31 can be easily bent in the direction of the stripes. Furthermore, when the stripes of the electrodes of the upper flexible substrate 32a and the stripes of the electrodes of the lower flexible substrate 32b are oriented in different directions, the amount of change in resistance value when pressure is applied to each location of the pressure sensor 31 can be made uniform.

[0041] In addition, the flexible substrate used in the pressure sensor 31 may be one provided with different numbers of electrodes, such as the flexible substrate 42a shown in FIG. 9A and the flexible substrate 42b shown in FIG. 9B. The upper flexible substrate 42a shown in FIG. 9A is provided with two electrodes formed in a roughly comb shape. The lower flexible substrate 42b shown in FIG. 9B is provided with one electrode formed in a roughly striped shape. In this case, the pressure sensor 31 can appropriately separate the pressure applied to the finger from other miscellaneous pressures by devising the wiring, as shown in FIG. 10. As a result, the pressure sensor 31 can eliminate the influence of unnecessary pressures detected by the pressure sensor of the prior art when the wearer of the wearable sensor 1c bends his / her finger.

[0042] The present invention is not limited to the above-described embodiment, and can be implemented using any components without departing from the spirit of the present invention.

[0043] The above-mentioned embodiments and modifications are merely examples, and the present invention is not limited to these contents as long as the characteristics of the invention are not impaired. In addition, although various embodiments and modifications have been described above, the present invention is not limited to these contents. Other aspects that are conceivable within the scope of the technical idea of ​​the present invention are also included in the scope of the present invention. [Explanation of symbols]

[0044] 1: Wearable sensors 11, 11a, 11b, 21, 31: Pressure sensor 12, 12a, 12b, 12c: Flexible substrate 13, 23, 33: Pressure-sensitive material 14, 14b: Protective film 15: Double-sided non-adhesive film 16: Protective film 17, 37a, 37b, 47a, 47b: Electrodes (wiring patterns) 18: Parts that are easy to bend 32a, 42a: Flexible substrate (upper side) 32b, 42b: Flexible board (lower side) 51: Surface where tensile stress acts 52: Surface where compressive stress acts

Claims

1. A glove-type wearable sensor, Gloves and Film-type pressure sensor Equipped with The pressure sensor is incorporated into a fingertip of the glove, three coordinate axis directions in the three-dimensional orthogonal coordinate system include a vertical direction of a sensor layer of the pressure sensor, a longitudinal direction of the pressure sensor, and a width direction of the pressure sensor in the same plane as the longitudinal direction, Detecting only the pressure applied to the wearer's fingertips after wearing the wearable sensor; The pressure sensor includes a flexible substrate, a sheet-like pressure-sensitive element, and a protective film, which are stacked in a vertical direction, a first double-sided non-adhesive film is interposed between the upper surface of the flexible substrate and the lower surface of the pressure-sensitive element, and a second double-sided non-adhesive film is interposed between the upper surface of the pressure-sensitive element and the lower surface of the protective film; A glove-type wearable sensor.

2. 2. The glove-type wearable sensor according to claim 1, wherein the longitudinal side surfaces of the pressure sensor are protected by a part of the protective film divided into a plurality of parts.

3. A glove-type wearable sensor, Gloves and Film-type pressure sensor Equipped with The pressure sensor is incorporated into a fingertip of the glove, three coordinate axis directions in the three-dimensional orthogonal coordinate system include a vertical direction of a sensor layer of the pressure sensor, a longitudinal direction of the pressure sensor, and a width direction of the pressure sensor in the same plane as the longitudinal direction, Detecting only the pressure applied to the wearer's fingertips after wearing the wearable sensor; The pressure sensor includes a flexible substrate, a pressure-sensitive element, and a protective film stacked in a vertical direction, the pressure-sensitive elements are arranged at approximately equal intervals in an internal space of the pressure sensor formed by the upper surface of the flexible substrate and the lower surface of the protective film, with the width direction of each element being the longitudinal direction of the pressure sensor; A glove-type wearable sensor.

4. The glove-type wearable sensor according to claim 3, a wiring pattern is formed on the flexible substrate so that positions at which the pressure-sensitive elements are arranged overlap with positions of wires; A glove-type wearable sensor.

5. The glove-type wearable sensor according to claim 3, the flexible substrate is formed to be easily bent at positions overlapping with the gaps provided between the pressure-sensitive elements; A glove-type wearable sensor.

6. The glove-type wearable sensor according to claim 1 or 3, The pressure-sensitive element is sandwiched between two of the flexible substrates, Each of the two flexible substrates is provided with a different positive or negative electrode. A glove-type wearable sensor.

7. 7. The glove-type wearable sensor according to claim 6, Each of the two flexible substrates is provided with electrodes formed in a substantially striped pattern, The orientation of the stripes of the electrodes on the upper flexible substrate and the orientation of the stripes of the electrodes on the lower flexible substrate are different from each other. A glove-type wearable sensor.

8. 7. The glove-type wearable sensor according to claim 6, The upper flexible substrate is provided with two or more electrodes formed in a generally comb-like shape, The lower flexible substrate is provided with one electrode formed in a substantially striped pattern. A glove-type wearable sensor.

9. A glove-type wearable sensor according to claim 1, The side surfaces of the pressure sensor are protected by adhesive films divided into a plurality of portions in the longitudinal direction. A glove-type wearable sensor.

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