JP6325289B2 - Sheet sensor system and sheet sensor - Google Patents

Description

  The present invention relates to a sheet sensor system for detecting a load acting on the surface of a detection target, and in particular, in each part of the surface of the detection target, it is possible to detect a distribution state of a shear load acting in a direction along the surface. The present invention relates to a sheet sensor system and a sheet sensor used for the sheet sensor system.

  For example, in a production site, automation of work by a robot hand is expected to improve work efficiency and safety. Since the surface of the robot is covered with metal or hard resin, there is a possibility of harm when it comes in contact with humans. Therefore, it is desired to arrange a sensor that can measure the load flexibly on the robot surface.

  As a flexible sensor currently being developed, there is a sensor that measures a contact state by using image processing. However, there is a problem that the amount of information is large and downsizing is difficult. In addition, a sensor using pressure-sensitive conductive rubber can measure only a vertical load and cannot measure a shear load or the like. In order to solve such a problem, the present inventors have proposed a flexible triaxial load measuring sensor and a four-axis load measuring sensor capable of measuring a vertical load and a shear load in Patent Documents 1 and 2. .

JP 2013-79831 A JP 2013-210368 A

  Here, using the sensors proposed in Patent Documents 1 and 2, a sensor system for measuring the distribution of vertical load and shear load acting on the surface of a large area such as a car seat or a bed is constructed. Therefore, it is conceivable to use the sensor proposed in Patent Documents 1 and 2. In this case, it is necessary to arrange a large number of sensors on the surface of the detection object at a predetermined pitch. Since the sensor system having this configuration requires a large number of sensors, there are problems such as high cost and an increase in the number of wires. Further, since the load detection resolution is restricted by the sensor arrangement density, there is a problem that it is difficult to increase the detection resolution.

  In view of such a point, the object of the present invention is to provide an inexpensive sheet sensor system capable of measuring a shear load acting on a large area surface and requiring a small number of wires, and a sheet sensor used in the sheet sensor system. It is to provide.

  Moreover, the subject of this invention is providing the sheet | seat sensor used for the sheet | seat sensor system which can improve load resolution, and the said sheet | seat sensor system in addition to said subject.

In order to solve the above-described problems, the sheet sensor system of the present invention includes:
A pressure-sensitive sheet made of a pressure-sensitive conductive material arranged in a range including a predetermined sensor pressure-receiving surface;
On one side of the pressure sensitive sheet, a common electrode arranged in a range including the sensor pressure receiving surface,
A plurality of individual electrodes sandwiched between the pressure sensitive sheets and disposed opposite to the common electrode,
An arithmetic unit that calculates a load acting on each part of the sensor pressure-receiving surface based on a voltage change amount generated between each of the common electrode and the individual electrode;
Have
The sensor pressure-receiving surface is divided into a plurality of detection sections,
When one direction along the sensor pressure-receiving surface is an x direction, a plurality of individual electrodes are arranged along the x direction in each of the detection sections,
The calculation unit calculates a magnitude of a shear load in the x direction acting on each detection section based on a voltage change amount between the common electrode and each of the plurality of individual electrodes of each detection section. It is said.

  In the sheet sensor system of the present invention, the shear load acting in the x direction is detected in each detection section based on the voltage change amount generated in each detection section calculated from the voltage change amount between the common electrode and each individual electrode. it can. In addition, the calculation unit can calculate the vertical load acting on each detection section and the vertical load acting on each part of the individual electrode based on the amount of voltage change between the common electrode and the individual electrode. .

  According to the present invention, the sensor portion can be configured more compactly and the number of wirings can be reduced as compared with the case where a large number of independent sensors are arranged on the surface of the detection target. Further, since the detection resolution is defined not by the arrangement density of the individual sensors but by the arrangement density of the detection sections, it is easy to increase the detection resolution as compared with the case where a large number of independent sensors are arranged.

  In the present invention, in order to detect a shear load in an arbitrary direction acting on the sensor pressure-receiving surface, it is only necessary that each detection section has at least two individual electrodes arranged in a direction orthogonal to the x direction.

  In this case, in the sheet sensor system of the present invention, in addition to the above configuration, if the direction along the sensor pressure-receiving surface orthogonal to the x direction is the y direction, each of the detection sections has an x direction and a y direction. A plurality of the individual electrodes are arranged along each of them, and the calculation unit generates a voltage change generated in each detection section calculated from a voltage change amount between the common electrode and each of the plurality of individual electrodes of each detection section. The magnitude and direction of the shear load Pt in any direction along the sensor pressure receiving surface acting on each detection section may be calculated based on the amount.

Here, in addition to the above-described configuration , the present invention is configured as follows in order to increase the load dividing ability . That is, the detection section has at least one of the individual electrodes arranged along the x direction belonging to the first detection section, where a pair of adjacent detection sections is a first detection section and a second detection section. The sensor pressure-receiving surface is divided into a plurality of detection sections so as to be included in the individual electrodes arranged along the x direction belonging to the second detection section.

  In addition to the configuration described above, also in the y direction, at least one of the individual electrodes arranged along the y direction belonging to the first detection section is arranged along the y direction belonging to the second detection section. Preferably, the sensor pressure-receiving surface is divided into a plurality of the detection sections so as to be included in the individual electrodes.

  In a typical configuration of the present invention, the individual electrodes are arranged in a lattice pattern at a predetermined pitch in each of the x direction and the y direction, and each of the detection sections includes four individual electrodes. .

  In the sheet sensor system of the present invention, the sheet sensor system includes an elastic sheet laminated in a state of covering the common electrode, or an elastic sheet laminated in a state of covering the pressure-sensitive sheet and the individual electrode, and the sheet surface of the elastic sheet A sensor pressure receiving surface may be defined.

In the sheet sensor system of the present invention, assuming that the components in the x and y directions of the arbitrary load P applied to each detection section and the z direction orthogonal thereto are Px, Py, and Pz,
The vertical load Pn (= Pz) acting on each detection zone, as shown in the following formula, calculated based on the sum of the voltage change amount dV ₁ ~dV ₄ of the four said individual electrodes belonging to the detection zone,
The shear load Pt acting on each detection section is calculated based on the voltage change amount ΔV of the four individual electrodes belonging to each detection section, as shown by the following equation:
When the direction of the shear load Pt acting on each detection section is represented by an angle φ counterclockwise from the x direction,
Can be calculated.

On the other hand, the present invention is a sheet sensor used in the sheet sensor system having the above-described configuration,
A pressure-sensitive sheet made of a pressure-sensitive conductive material arranged in a range including a predetermined sensor pressure-receiving surface;
On one side of the pressure sensitive sheet, a common electrode arranged in a range including the sensor pressure receiving surface,
A plurality of individual electrodes sandwiched between the pressure sensitive sheets and disposed opposite to the common electrode,
Have
The sensor pressure-receiving surface is divided into a plurality of detection sections,
When two orthogonal directions along the sensor pressure-receiving surface are defined as an x direction and a y direction, a plurality of the individual electrodes are arranged along the x direction and the y direction in each of the detection sections. It is characterized by that.

(A) is a schematic block diagram of the sheet | seat sensor system to which this invention is applied, (b) is a schematic diagram which shows the cross-sectional structure of the sheet | seat sensor. It is explanatory drawing which shows the detection division set to the sensor pressure-receiving surface of a sheet sensor. (A) is explanatory drawing which shows one detection division of a sheet sensor, (b) is a circuit diagram which shows the equivalent circuit. (A)-(c) is a schematic diagram for demonstrating a load measurement principle. (A) And (b) is explanatory drawing which shows a load measurement procedure. (A) is a schematic diagram which shows an example of an experimental apparatus, (b) is explanatory drawing which shows a load application position. It is explanatory drawing which shows the example of a screen display which shows the distribution state of the measured shear load vector, and the distribution state of a perpendicular load. (A) is a chart showing the relationship between the voltage change amount generated in each zone and the shear load obtained by the experiment, (b) is a chart showing the relationship between the voltage change and the shear load obtained by the experiment, c) is an explanatory diagram showing the position of each zone. It is explanatory drawing which shows an example of the arrangement pattern of an individual electrode.

  Hereinafter, embodiments of a sheet sensor system and a sheet sensor to which the present invention is applied will be described with reference to the drawings.

(overall structure)
FIG. 1A is a schematic configuration diagram illustrating a sheet sensor system according to the present embodiment, and FIG. 1B is a schematic diagram illustrating a cross-sectional configuration of the sheet sensor. As shown in FIG. 1A, a sheet sensor system 1 includes a sheet sensor 2, a stabilized power supply 3 that supplies power to the sheet sensor 2, a voltage detector 4 that detects an output voltage of the sheet sensor 2, and a voltage. A controller 5 is provided that is configured mainly by a computer that performs a calculation process based on a voltage detection value by the detector 4 and calculates a load acting on each part of the sensor pressure-receiving surface 20 of the sheet sensor 2.

  As shown in FIGS. 1A and 1B, the sheet sensor 2 includes a common electrode 22 formed on the upper surface of the lower electrode substrate 21 and a large number of individual electrodes formed on the lower surface of the upper electrode substrate 23. A pressure sensitive sheet 25 made of a pressure sensitive conductive material and having a certain thickness is sandwiched between the electrodes 24. A surface plate 26 made of an elastic material is laminated on the upper surface of the upper electrode substrate 23. The upper surface of the surface plate 26 is the sensor pressure receiving surface 20.

  The common electrode 22 formed on the lower electrode substrate 21 is formed over a range including the sensor pressure receiving surface 20. As shown in FIG. 1A, the common electrode 22 in this example is an electrode layer having a rectangular outline indicated by a thick broken line frame including a sensor pressure-receiving surface 20 having a rectangular outline indicated by a thick line frame. On the other hand, each of the individual electrodes 24 is a square outline electrode having the same size. As shown in FIG. 1A, the individual electrodes 24 are arranged in a grid pattern at the same interval p in the vertical and horizontal directions, and the individual electrodes 24 are electrically separated from each other.

  In the figure, 36 square individual electrodes 24 are arranged in a rectangular area corresponding to the sensor pressure-receiving surface 20 so as to form a 6-row 6-column grid. The shape of the sensor pressure-receiving surface 20 is not limited to a rectangle, and can be an arbitrary shape such as a polygon or a circle. Similarly, the shape of the individual electrode 24 is not limited to a rectangle, and may be various shapes such as a polygon, a circle, and a line. Needless to say, the number of individual electrodes 24 arranged is not limited to 36.

For example, glassy carbon (hereinafter referred to as “GC”) and vapor-grown carbon fiber (hereinafter referred to as “VGCF”) are added to the GC in the pressure-sensitive conductive material forming the pressure-sensitive sheet 25. The composite material GC / VGCF can be used. GC / VGCF is effective as a conductive material that can be used at high temperatures, similar to glassy carbon. Further, since GC and GC / VGCF are conductive composite materials, their electric resistance values change when a load is applied while applying a voltage. For example, GC / 20 wt% VGCF in which VGCF is added to GC by 12 wt% by mass ratio can be used. In addition, a composite material in which an arbitrary resin such as a thermosetting resin, a thermoplastic resin, or an engineering plastic is used as a matrix material (base material) and a filler material shown in Table 1 is added can be used. In addition, flake shape, powder shape, fiber shape, etc. are applicable as a shape added in a composite material.

  For the lower electrode substrate 21 and the upper electrode substrate 23, a flexible film, for example, a flexible film made of polyester can be used. The individual electrode 24 can be formed on the upper electrode substrate 23 by etching. The surface plate 26 can be made of, for example, silicone rubber. Thereby, the flexible laminated film sheet sensor 2 is configured. Here, in some cases, the surface plate 26 may be omitted. When the sheet sensor 2 is installed on a flat surface for detection, a glass epoxy rigid substrate can be used as the electrode substrate opposite to the sensor pressure receiving surface 2a.

  In the sheet sensor 2 having this configuration, a power supply wiring pattern for applying a DC voltage is formed between the common electrode 22 and the individual electrode 24. The power supply wiring pattern is connected to the stabilized power supply 3 from the sensor terminal portion 27 via the power supply line 28. The stabilized power source 3 applies a constant DC voltage between the common electrode 22 and the individual electrode 24 (between the counter electrodes) facing each other with the pressure-sensitive sheet 25 therebetween. The electric resistance value of each part of the pressure sensitive sheet 25 varies depending on the load applied from the sensor pressure receiving surface 20.

  The sheet sensor 2 is provided with a detection wiring pattern for detecting a voltage value between the common electrode 22 and the individual electrode 24 that varies with load application. The detection wiring pattern is connected to the voltage detector 4 from the sensor terminal portion 29 via the detection line 30. The voltage detector 4 detects the voltage between the opposing electrodes. In the controller 5, the magnitude of the vertical load component in the arbitrary load applied to the sensor pressure receiving surface 20 and the magnitude of the shear load component in the direction along the sensor pressure receiving surface 20 in the calculation unit 51 based on the detected voltage value between the opposing electrodes. The length and direction are calculated for each detection section including the four individual electrodes 24 as described below.

  FIG. 2 is an explanatory view showing a detection section for load detection on the sheet pressure receiving surface 20. The calculation unit 51 of the controller 5 performs load detection in units of detection sections. In this example, the four individual electrodes 24 arranged adjacent to each other in the vertical and horizontal directions are used as one load detection unit. Therefore, the sensor pressure receiving surface 20 is conceptually configured to include the four individual electrodes 24. It is divided into 25 detection sections of the same shape. That is, as shown by the solid line frame, the sensor pressure receiving surface 20 has nine detection sections 20A, and as shown by the broken line frame, 15 detection sections overlap with the detection sections of the adjacent solid line frame. 20B is formed. When an arbitrary load is applied to the sensor pressure-receiving surface 20, the vertical load is applied as described later based on the detected voltage values from the four individual electrodes 24 for each of the detection sections 20 (n) (n = 1 to 25). The size of the component, the size and direction of the shear load component can be calculated.

  When an independent sensor having four individual electrodes is arranged on the same sensor pressure-receiving surface 20, as shown by a solid line frame in FIG. Load detection is possible only in the detection section 20A. In the case of this example, as shown by the solid line frame and the broken line frame, it is possible to detect the load in the five detection areas 20A and 20B of 5 rows and 5 columns on the same sensor pressure receiving surface 20. In other words, the detection resolution can be increased by using the same number of individual electrodes 24.

(Load measurement principle)
Next, the principle of load measurement in each detection section will be described with reference to FIGS. FIG. 3A is an explanatory view showing one detection section 20 (n) (n = 1 to 25) in the sheet sensor 2. FIG. As shown in this figure, in the detection section 20 (n), directions that are parallel to the pressure receiving surface and orthogonal to each other are defined as an x direction and a y direction, respectively, and directions orthogonal to these directions (directions orthogonal to the sensor pressure receiving surface 2a). The z direction is assumed. One of the x direction from the center of the detection section 20 (n) is a positive direction, similarly, one of the y direction from the center is a positive direction, and the positive direction of the x direction and the y direction in the detection section 20 (n) is a zone. 1, and the center of the detection section 20 (n) is defined as a zone 2, a zone 3, and a zone 4 counterclockwise around the central axis extending in the z direction.

FIG. 3B is a circuit diagram showing an equivalent circuit of a portion including the detection section 20 (n) of the sheet sensor system 1. V ₀ is the voltage of the stabilized power supply 3, R is a resistance for voltage division, R _{1 to} R ₄ are variable resistances at portions corresponding to the individual electrodes 24 m in the pressure sensitive sheet 25, and V ₁ ~V ₄ shows the potential difference between the each of the common electrode 22 four individual electrodes 24m (m = 1~4). When the voltage change amount of each zone m is dVm, it is expressed as dVm = V ₀ −Vm.

FIG. 4A is a schematic diagram showing a relationship between an arbitrary load P applied to the detection section 20 (n) and a voltage change amount in each of the zones 1 to 4. As shown in FIG. The loads P _{1 to} P ₄ acting on the zones 1 to ₄ are expressed by the following equations using voltage change amounts dV _{1 to} dV ₄ as vector quantities.

The arbitrary load P is the sum of the loads P _{1 to} P ₄ applied to each zone m, and the arbitrary load P is expressed as follows using the voltage change amounts dV _{1 to} dV ₄ .

Here, as shown in FIG. 4B, the arbitrary load P can be decomposed into x, y and z direction components, the z direction component corresponds to the vertical load, and the resultant force of the x and y direction components is shear. Corresponds to load. If the components in the x, y, and z directions are Px, Py, and Pz, respectively, the arbitrary load P is expressed by the following equation using the components Px, Py, and Pz.

Therefore, the vertical load Pn can be calculated based on the sum of the voltage change amounts of the zones 1 to 4 as shown by the following equation.

Further, the shear load Pt can be expressed by using x and y components Px and Py of an arbitrary load P as shown in the following formula, and the components Px and Py are voltage change amounts dV _{1 of the} zones 1 to 4. ~ DV ₄ can be used. Therefore, the shear load Pt can be calculated based on the voltage change amount ΔV of each zone 1 to 4.

Furthermore, as shown in FIG. 4C, when the direction of the shear load Pt is represented by an angle φ counterclockwise from the x direction, the shear load is based on the ratio of the components Py and Px as shown in the following equation. The direction φ of Pt can be obtained. The acting direction of the arbitrary load P with respect to the xy plane can be similarly obtained from the ratio of the vertical load Pn that is the vertical component of the arbitrary load P and the shear load Pt that is the horizontal component.

(Example of load measurement procedure)
In the specific load measurement using the sheet sensor system 1, in the sheet sensor 2, when an arbitrary load is applied to the sensor pressure receiving surface 20, the amount of voltage change generated in the four zones of the detection section 20 (n). Relationship between dVm and generated shear load Pt, relationship between voltage change ΔV generated in detection section 20 (n) and shear load Pt, relation of voltage change in each detection section with respect to load application position of sensor pressure-receiving surface 20, etc. Are measured in advance. Based on the relationship obtained by the measurement, a calculation formula for calculating the magnitude of the vertical load, the magnitude of the shear load, and the direction based on the above formulas is set. In the calculation part 51 of the controller 5, based on the detection voltage change dVm detected from each zone 1-4 in each detection section 20 (n), the vertical load Pn is calculated, and the voltage generated in each detection section 20 (n). Calculation of the magnitude of the shear load Pt based on the change amount ΔV, calculation of the direction of the shear load Pt, and the like are performed.

  FIG. 5 shows an example of a specific load measurement procedure. For example, as shown in FIG. 5A, four individual electrodes 24 (1.1) and 24 (1.2) of the detection section 20 (1) surrounded by a solid line located at the corner of the rectangular sensor pressure-receiving surface 20 , 24 (2.1), 24 (2.2), the vertical load Pn (1) and the shear load Pt (1) acting on the detection section 20 (1) are calculated.

  Next, as shown in FIG. 5B, the four individual electrodes 24 (1.2) and 24 (1.3) are shifted in the width direction W of the sensor pressure-receiving surface 20 by one individual electrode. ), 24 (2.2), 24 (2.3), a vertical load Pn (2) and a shear load Pt (2) acting on the detection section 20 (2) surrounded by a solid line are calculated.

Thus, on the sensor pressure-receiving surface 20, along the width direction W and the longitudinal direction L, the vertical load Pn and the 25 detection sections 20 (n) each including four individual electrodes 24 are sequentially A shear load Pt is calculated. Thereby, load detection can be performed at 25 positions on the sensor pressure-receiving surface 20. As described above with reference to FIG. 2, when an independent sensor having four individual electrodes 24 is arranged on the sensor pressure receiving surface 20 and load detection is performed, only nine detection points are detected. It is. Therefore, according to the sheet sensor system 1 of the present example, it is possible to detect the shear load with higher resolution than in the past.

(Experimental example)
FIG. 6A is a schematic diagram of an experimental apparatus using the sheet sensor system 1, and FIG. 6B is a schematic diagram showing a load load position. The experimental apparatus 100 placed the sheet sensor 2 of the sheet sensor system 1 on the 6-axis load cell 102 on the XY stage 101, and applied a load using the loading mechanism 103 from above. The diameter of the indenter 104 of the loading mechanism 103 was 20 mm, the vertical load Pn was constant at 20 N, and the load application position was the center of the sensor pressure receiving surface 2 a of the sheet sensor 2. While gradually increasing the shear load Px in the x direction from 0N, the distribution state of the vertical load Pn and the shear load Pt generated in each detection section 20 (n) was calculated based on the detection voltage of each individual electrode 24. As the sheet sensor 2, as shown in FIG. 6B, a sheet sensor having a configuration in which eight individual electrodes 24 in the vertical and horizontal directions are arranged on the sensor pressure receiving surface 2a was used.

  FIG. 7 is an explanatory diagram showing a screen display example of the distribution of shear load vectors and the distribution of vertical loads obtained by experiments. FIGS. 7A1 and 7A2 show the case where the vertical load Pn = 20N and the shear load Px0N. FIGS. 7B1 and 7B2 show the case where the vertical load Pn = 20N and the shear load Px = 6.5N. FIGS. 7C1 and 7C2 show the results when the vertical load Pn = 20N and the shear load Px = 12.1N.

FIG. 8A is a graph showing the relationship between the voltage change amount ΔVm generated in the four zones 1 to 4 and the shear load Px in the detection section 20 (n) at the center of the sheet sensor 2 measured by the experiment. FIG. 8B is a chart showing the relationship between the voltage change Vpx and the shear load Px. As shown in FIG. 8C, the four zones in the detection section 20 (n) to be measured are the zone (4.4), the zone (4.5), the zone (5.5), and the zone (5. 4). Assuming that the amount of voltage change occurring in these zones is ΔV (4.4), ΔV (4.5), ΔV (5.5), ΔV (5.4), as shown in the following equation, the detection section 20 ( The voltage change Vpx appearing in n) is calculated.

  As can be seen from the charts of FIGS. 8A and 8B, a predetermined correlation is confirmed between the voltage change amount ΔVm and the shear load Px, and a predetermined correlation is also observed between the voltage change Vpx and the shear load Px. It is confirmed. Therefore, the size and direction (distribution) of the shear load as well as the magnitude of the vertical load generated in each detection section 20 (n) by the load applied to the sheet pressure receiving surface 20 by using the sheet sensor system 1 of this example. It can be seen that can be measured.

(Other embodiments)
In the sheet sensor 2 described above, individual electrodes are arranged in a matrix on the sheet pressure receiving surface 20, and each detection section 20 (n) includes two individual electrodes vertically and horizontally. The acting shear load can be detected. The number of individual electrodes included in one detection section may be two, three, or five or more.

Moreover, when the direction of the shearing force to be detected is one direction, a detection section in which a plurality of individual electrodes are arranged in the direction may be configured. For example, as shown in FIG. 9, when a plurality of individual electrodes 24 are arranged linearly in the x direction, the shear load acting in the x direction can be measured. In this case, based on the detection voltage values of the two individual electrodes 20 (1) and 20 (2), the vertical load acting on the detection section 20 (1) including them and the shear load in the x direction are calculated. Next, the operation of calculating the load may be repeated in the next detection section shifted in the x direction by one individual electrode. Of course, the load calculation may be performed by setting a detection section including three or more individual electrodes as the detection section.

DESCRIPTION OF SYMBOLS 1 Sheet sensor system 2 Sheet sensor 3 Stabilized power supply 4 Voltage detector 5 Controller 20 Sensor pressure receiving surface 21 Lower electrode substrate 22 Common electrode 23 Upper electrode substrate 24 Individual electrode 25 Pressure sensitive sheet 26 Surface plate 27, 29 Sensor terminal part 28 Feed line 30 Detection line 51 Calculation unit

Claims (8)

A pressure sensitive sheet (25) made of a pressure sensitive conductive material arranged in a range including a predetermined sensor pressure receiving surface (20);
On one side of the pressure sensitive sheet (25), a common electrode (22) disposed in a range including the sensor pressure receiving surface (20),
A plurality of individual electrodes (24) disposed opposite to the common electrode (22) with the pressure-sensitive sheet (25) interposed therebetween;
A calculation unit (51) for calculating a load acting on each part of the sensor pressure-receiving surface (20) based on a voltage change amount generated between each of the common electrode (22) and the individual electrode (24);
Have
The sensor pressure-receiving surface (20) is divided into a plurality of detection sections (20 (n)),
When the direction of one along said sensor pressure receiving surface (20) and the x direction, each of said detection zone (20 (n)), the plurality of individual electrodes along the x-direction are arranged,
The calculation unit (51) detects each detection based on a voltage change amount (dVm) between the common electrode (22) and each of the plurality of individual electrodes (24) of each detection section (20 (n)). Calculate the magnitude of shear load (Pt) in the x direction acting on the compartment (20 (n)) ,
When a pair of adjacent detection sections is a first detection section (20 (1)) and a second detection section (20 (2)),
At least one of the individual electrodes (24 (1.2)) arranged along the x direction belonging to the first detection section (20 (1)) is the second detection section (20 (2)). The sensor pressure-receiving surface (20) is divided into a plurality of detection sections (20 (n)) so as to be included in the individual electrodes arranged along the x direction belonging to the sheet. Sensor system (1). When the direction along the sensor pressure-receiving surface (20) perpendicular to the x direction is the y direction,
In each of the detection sections (20 (n)), a plurality of the individual electrodes (24) are arranged along the x direction and the y direction,
The calculation unit (51) detects each detection based on a voltage change amount (dVm) between the common electrode (22) and each of the plurality of individual electrodes (24) of each detection section (20 (n)). Calculating the magnitude and direction (φ) of the shear load (Pt) in any direction along the sensor pressure-receiving surface (20) acting on the section (20 (n));
The sheet sensor system (1) according to claim 1. At least one of the individual electrodes (24 (2.2)) arranged along the y direction belonging to the first detection section (20 (1)) is the second detection section (20 (2)). The sensor pressure-receiving surface (20) is divided into a plurality of detection sections (20 (n)) so as to be included in the individual electrodes arranged along the y direction belonging to
The sheet sensor system (1) according to claim 2. The individual electrodes (24) are arranged in a lattice pattern at a predetermined pitch in each of the x direction and the y direction,
Each of the detection sections (20 (n)) includes four individual electrodes (24),
The sheet sensor system (1) according to claim 3. The computing unit (51) acts on each of the detection sections (20 (n)) based on a voltage change amount (dVm) between each of the common electrode (22) and the individual electrode (24). Calculating at least one of a vertical load (Pn) and a vertical load acting on each part of the individual electrode (24);
The sheet sensor system (1) according to any one of claims 1 to 4. An elastic sheet (26) laminated to cover the common electrode (22), or an elastic sheet (26) laminated to cover the pressure sensitive sheet (25) and the individual electrode (24),
The sensor pressure-receiving surface (20) is defined by the sheet surface of the elastic sheet (26).
A sheet sensor system (1) according to any one of the preceding claims. Assuming that the components in the x and y directions of the arbitrary load applied to each detection section (20 (n)) and the z direction orthogonal thereto are Px, Py, and Pz, the calculation unit (51)
Each detection zone (20 (n)) vertical load Pn acting on (= Pz), as shown in the following formula, the sum of the voltage change amount _dV 1 _{~dV 4} of the four said individual electrodes belonging to the detection zone Based on
The shear load Pt acting on each detection section is calculated based on the voltage change amount ΔV of the four individual electrodes belonging to each detection section, as shown by the following equation:
When the direction of the shear load Pt acting on each detection section is represented by an angle φ counterclockwise from the x direction around the axis in the z direction,
Calculated by
The sheet sensor system (1) according to claim 4. A sheet sensor (2) used in the sheet sensor system (1) according to any one of claims 1 to 7,
A pressure sensitive sheet (25) made of a pressure sensitive conductive material arranged in a range including a predetermined sensor pressure receiving surface (20);
On one side of the pressure sensitive sheet (25), a common electrode (22) disposed in a range including the sensor pressure receiving surface (20),
A plurality of individual electrodes (24) disposed opposite to the common electrode (22) with the pressure-sensitive sheet (25) interposed therebetween;
Have
The sensor pressure-receiving surface (20) is divided into a plurality of detection sections (20 (n)),
Assuming that two orthogonal directions along the sensor pressure receiving surface (20) are an x direction and a Y direction, each of the detection sections (20 (n)) includes a plurality of directions along each of the x direction and the y direction. the sheet sensor, characterized in that the individual electrodes (24) are arranged in (2).