WO2020079967A1

WO2020079967A1 - Displacement detection sensor

Info

Publication number: WO2020079967A1
Application number: PCT/JP2019/034068
Authority: WO
Inventors: 暢謙森田; 正道安藤
Original assignee: 株式会社村田製作所
Priority date: 2018-10-19
Filing date: 2019-08-30
Publication date: 2020-04-23
Also published as: JP6973630B2; JPWO2020079967A1

Abstract

A displacement detection sensor (1) is provided with a substrate (10) on which a first detection object and a second detection object are arranged, a first detection part (11) for detecting displacement in a first direction, and a second detection part (12) for detecting displacement in a second direction different from the first direction, the first detection part (11) and the second detection part (12) being arranged on the substrate (10), the first detection part (11) being arranged in at least the first detection object, and the second detection part (12) being arranged in at least the second detection object.

Description

Displacement detection sensor

The present invention relates to a displacement detection sensor that detects displacement of a detection target.

Patent Document 1 discloses a glove with a sensor in which a bending sensor is arranged at a position from the wrist to the back of the hand on the back side of the hand. The sensor of Patent Document 1 includes a base material of a plastic sheet.

Japanese Patent Laid-Open No. 5-285249

The glove with the sensor of Patent Document 1 can detect only one-way displacement such as wrist bending. Therefore, the glove with a sensor of patent document 1 cannot detect a complicated motion.

Therefore, an object of the present invention is to provide a displacement detection sensor capable of detecting displacements in a plurality of directions.

A displacement detection sensor of the present invention includes a base material arranged on a first detection target and a second detection target, a first detection unit that detects displacement in a first direction, and a first detection unit that is different from the first direction. A second detection unit that detects displacement in two directions, the first detection unit and the second detection unit are disposed on the base material, and the first detection unit is at least the first detection unit. The second detection unit is arranged at least on the second detection target.

According to this invention, it is possible to detect displacements in a plurality of directions.

FIG. 1 is an external perspective view of a glove provided with a displacement detection sensor. 2A is a plan view of the displacement detection sensor, FIG. 2B is a sectional view taken along the line AA, and FIG. 2C is a bottom view. FIG. 3 is a sectional view of the first piezoelectric element 11. FIG. 4 is a sectional view of the displacement detection sensor during a bending operation. 5A is a rear perspective view of the displacement detection sensor when the torsional displacement is 0, and FIG. 5B is a rear perspective view of the displacement detection sensor when a predetermined torsional displacement is generated. FIG. 6 is an external perspective view of the globe 5A according to the first modification. 7A is a plan view of a displacement detection sensor 1A according to Modification 1, FIG. 7B is a cross-sectional view taken along the line AA, and FIG. 7C is a bottom view. . 8A is a plan view of a displacement detection sensor 1B according to Modification 2, FIG. 8B is a cross-sectional view taken along the line AA, and FIG. 8C is a bottom view. . 9A is a plan view of a displacement detection sensor 1C according to Modification 3, and FIG. 9B is a sectional view taken along the line AA. FIG. 10 is an external perspective view of a globe 5D according to Modification 4. FIG. 11 is a plan view of a displacement detection sensor 1D according to Modification 4.

FIG. 1 is an external perspective view of a glove 5 equipped with the displacement detection sensor of the present invention. The glove 5 is made of a material such as elastomer and has a shape that covers the entire hand and wrist. However, the glove 5 does not need to have a shape that covers the fingertip.

The displacement detection sensor 1 is arranged on the palm side of the glove 5. The displacement detection sensor 1 has a rectangular shape in plan view. The displacement detection sensor 1 is arranged along the base of the middle finger from the wrist part. The displacement detection sensor 1 is arranged over a palm region 101, a wrist joint region 102, and a wrist region 103. The palm region 101 is an example of the first detection target in the present invention, and the wrist region 103 is an example of the second detection target in the present invention. The displacement detection sensor 1 may be arranged on the back side of the hand. In this case, the area of the back of the hand becomes the first detection target.

2A is a plan view of the displacement detection sensor 1, FIG. 2B is a cross-sectional view taken along the line AA, and FIG. 2C is a bottom view.

The displacement detection sensor 1 includes a base material 10, a first piezoelectric element 11 arranged on the first main surface of the base material 10, and a second piezoelectric element 12 arranged on the second main surface of the base material 10. I have it. The 1st piezoelectric element 11 is an example of the 1st primary detecting element of the present invention, and the 2nd piezoelectric element 12 is an example of the 2nd primary detecting element of the present invention.

The base material 10 is made of a highly flexible material such as PI (polyimide) or urethane. The base material 10, the first piezoelectric element 11, and the second piezoelectric element 12 each have a rectangular shape in plan view. The areas of the first piezoelectric element 11 and the second piezoelectric element 12 are the same, and each is slightly smaller than the base material 10. However, in the present invention, the areas of the first piezoelectric element 11 and the second piezoelectric element 12 do not have to be the same.

FIG. 3 is a sectional view of the first piezoelectric element 11. Since the second piezoelectric element 12 has the same cross-sectional structure as the first piezoelectric element 11, the structure of the first piezoelectric element 11 is shown as a representative in FIG.

The first piezoelectric element 11 includes a first protective layer 50, a conductive thin film member 51, an intermediate layer 52, a detection electrode 53, a piezoelectric film 54, and a second protective layer 55. The lower surface of the first protective layer 50 is attached to the base material 10.

The first protective layer 50, the intermediate layer 52, and the second protective layer 55 are made of, for example, PET (polyethylene terephthalate), PC (polycarbonate), PMMA (acrylic resin), COP (cycloolefin polymer), or the like. The first protective layer 50 and the second protective layer 55 have a shape that covers the entire first piezoelectric element 11. The first protective layer 50 and the second protective layer 55 have a function of protecting the first piezoelectric element 11, although they are not essential in the present invention. In addition, when the first protective layer 50 and the second protective layer 55 are made of a polyethylene foam film or the like, they can also exhibit waterproofness by covering the first piezoelectric element 11. The first piezoelectric element 11 may be molded with a highly flexible material such as polyurethane or silicone.

The conductive thin film member 51 is attached to the upper surface of the first protective layer 50. The intermediate layer 52 is attached to the upper surface of the conductive thin film member 51. The detection electrode 53 is arranged on the upper surface of the intermediate layer 52. A piezoelectric film 54 is arranged on the upper surface of the detection electrode 53. The conductive thin film member 51 is attached to the upper portion of the piezoelectric film 54. That is, the conductive thin film member 51 is configured to sandwich and cover the intermediate layer 52, the detection electrode 53, and the piezoelectric film 54 from above and below. The second protective layer 55 is attached to the upper surface of the conductive thin film member 51.

The intermediate layer 52 is arranged at the position closest to the piezoelectric film 54. As shown in FIG. 4, when the displacement detection sensor 1 is convexly bent and deformed to the upper surface side, the lower surface side of the displacement detection sensor 1 contracts and the upper surface side extends. That is, inside the displacement detection sensor 1, there is a portion (neutral surface of stress) that does not expand or contract.

The first protective layer 50 is thicker than the second protective layer 55. The intermediate layer 52 is thinner than the second protective layer 55. The first protective layer 50 is thickest. If the first piezoelectric element 11 has a vertically symmetrical shape with the piezoelectric film 54 interposed therebetween, the neutral plane of stress may be located at the piezoelectric film 54. If the neutral surface of the stress is located at the position of the piezoelectric film 54, charges having different polarities are generated to the same extent inside the piezoelectric film 54. Since the generated charges having different polarities cancel each other, there is a possibility that a large output cannot be obtained from the piezoelectric film 54. However, in the first piezoelectric element 11 of the present embodiment, since the first protective layer 50 is thick, the neutral surface of the stress is located on the first protective layer 50 side, the intermediate layer 52, or the detection electrode 53. To do. Therefore, the piezoelectric film 54 generates an electric charge with respect to the bending displacement. In the present embodiment, the neutral surface of the stress may not be located on the piezoelectric film 54. For example, the detection electrodes 53 may have different thicknesses, or the detection electrodes 53 may have the same thickness and different electrode hardnesses.

The piezoelectric film 54 has a rectangular shape in plan view. The detection electrode 53 is arranged so as to cover substantially the entire first main surface of the piezoelectric film 54. The detection electrode 53 is made of, for example, aluminum or copper foil deposited on the intermediate layer 52. The detection electrode 53 is attached to the upper surface of the piezoelectric film 54 with an adhesive or the like (not shown).

The conductive thin film member 51 is arranged so as to cover the upper surface of the piezoelectric film 54 and the lower surface of the intermediate layer 52. As the conductive thin film member 51, for example, a conductive non-woven fabric on which an adhesive is formed, or a resin-impregnated copper foil on which an adhesive is formed is used. The conductive thin film member 51 functions as a ground conductor (shield conductor). As the detection electrode 53, a conductive non-woven fabric having a pressure sensitive adhesive formed thereon or a resin-impregnated copper foil having a pressure sensitive adhesive formed thereon may be used.

The piezoelectric film 54 is made of a chiral polymer. In particular, the piezoelectric film 54 is preferably uniaxially stretched polylactic acid (PLA), more preferably L-type polylactic acid (PLLA) or D-type polylactic acid (PDLA).

A chiral polymer has a helical structure in its main chain and has piezoelectricity when the molecules are uniaxially stretched and the molecules are oriented. The piezoelectric constant of uniaxially stretched PLLA belongs to a very high class among polymers. In addition, since the chiral polymer has piezoelectricity due to molecular orientation treatment such as stretching, it is not necessary to perform poling treatment unlike other polymers such as PVDF and piezoelectric ceramics. Therefore, the piezoelectric constant of PLLA does not fluctuate over time and is extremely stable. Furthermore, since polylactic acid has no pyroelectricity, the amount of electric charge detected does not change even when heat from the hand is transmitted.

Note that the draw ratio is preferably about 3 to 8 times. By performing heat treatment after stretching, crystallization of the extended chain crystal of polylactic acid is promoted and the piezoelectric constant is improved. In the case of biaxial stretching, the same effect as uniaxial stretching can be obtained by changing the stretching ratio of each axis. For example, when a certain direction is set as the X-axis and the drawing is performed 8 times in the X-axis direction and 2 times in the Y-axis direction orthogonal to the X-axis, the piezoelectric constant is uniaxially drawn 4 times in the X-axis direction. The effect is almost the same as the case. Since a film that is simply uniaxially stretched tends to tear along the stretching axis direction, the strength can be somewhat increased by performing the biaxial stretching as described above.

In the present embodiment, the piezoelectric film 54 of the first piezoelectric element 11 forms an angle of approximately 45 ° in the uniaxial stretching direction with respect to the major axis direction of the displacement detection sensor 1, as shown by the white arrow in FIG. It is arranged to make up. The piezoelectric film 54 of the second piezoelectric element 12 is arranged in the uniaxial stretching direction along the long axis direction of the displacement detection sensor 1, as shown by the white arrow in FIG.

The first piezoelectric element 11 can detect bending deformation. As shown in FIG. 4, when the displacement detection sensor 1 is bent and displaced, the displacement detection sensor 1 is curved along the longitudinal direction. In this case, the upper surface side of the first piezoelectric element 11 extends along the longitudinal direction. As a result, the piezoelectric film 54 of the first piezoelectric element 11 generates electric charges according to the amount of expansion. The displacement detection sensor 1 detects a bending displacement and its bending amount based on the voltage detected by the detection electrode 53. As shown in FIG. 1, the displacement detection sensor 1 is arranged over a palm region 101, a wrist joint region 102, and a wrist region 103. Therefore, the displacement detection sensor 1 can detect the displacement of the palm region 101 caused by the operation when the hand is opened and when the hand is grasped. Further, the displacement detection sensor 1 can also detect the displacement of the wrist joint region 102 caused by the operation when the wrist joint is bent.

On the other hand, FIG. 5A is a rear perspective view of the displacement detection sensor when the torsional displacement is 0, and FIG. 5B is a rear perspective view of the displacement detection sensor when a predetermined torsional displacement occurs. is there.

As shown in FIG. 5A, when the torsional displacement is 0, the main surface of the base material 10 and the second piezoelectric element 12 is in a flat state. In this case, the second piezoelectric element 12 does not expand and contract, and no charge is generated in the piezoelectric film 54 of the second piezoelectric element 12.

When the base material 10 is twisted, the base material 10 moves in opposite directions along the normal direction at two corners in the longitudinal direction, as shown in FIG. 5 (B). As a result, the piezoelectric film 54 on one side of the two corners of the second piezoelectric element 12 expands and the piezoelectric film 54 on the other side contracts.

The piezoelectric film 54 of the second piezoelectric element 12 is arranged in the uniaxial stretching direction along the longitudinal direction. Therefore, the piezoelectric film 54 stretches in the direction of + 45 ° with respect to the uniaxial stretching direction at the corner on one side and in the vicinity thereof, and in the direction of −45 ° with respect to the uniaxial stretching direction at the corner of the other side and its vicinity. Contract to. Therefore, in the piezoelectric film 54, an electric charge is generated according to the extension or contraction of the corner caused by the twist.

The displacement detection sensor 1 detects the twist displacement and the amount of twist based on the voltage detected by the detection electrode 53. As shown in FIG. 1, the displacement detection sensor 1 is arranged over a palm region 101, a wrist joint region 102, and a wrist region 103. Therefore, the displacement detection sensor 1 can detect the twist displacement of the wrist region 103 and the twist amount caused by the wrist twisting operation.

The uniaxial stretching direction of the piezoelectric film 54 of the first piezoelectric element 11 is 45 ° with respect to the longitudinal direction, which coincides with the expansion / contraction direction caused by twisting. Therefore, in the piezoelectric film 54 of the first piezoelectric element 11, no electric charge is generated due to the twist displacement. Further, the uniaxial stretching direction of the piezoelectric film 54 of the second piezoelectric element 12 is along the longitudinal direction, and therefore coincides with the expansion / contraction direction caused by bending. Therefore, in the piezoelectric film 54 of the second piezoelectric element 12, electric charges are not generated by bending displacement.

The first piezoelectric element 11 is arranged at least along the palm region 101. The second piezoelectric element 12 is arranged at least along the wrist region 103. Therefore, the displacement detection sensor 1 is configured such that the displacement of the palm region 101 which is the first detection target (the displacement caused by the action of gripping the hand and the action of opening the hand) and the displacement of the region 103 of the wrist which is the second detection target. (Displacement caused by twisting wrist) can be detected individually and with high accuracy. Therefore, the displacement detection sensor 1 can individually detect the movement of the user's hand and the movement of the wrist with high sensitivity when the user is exercising, training, or rehabilitating.

Note that even if the hand does not move, for example, when the palm is pushed forward in water, water pressure is applied to the palm, and the displacement detection sensor 1 is bent and displaced. Therefore, the displacement detection sensor 1 can also highly accurately detect an action such as pushing out water when the user is exercising, training, or rehabilitating in water.

Also, in the displacement detection sensor 1, the first piezoelectric element 11 and the second piezoelectric element 12 are arranged on the same base material 10. Therefore, it is not necessary to separately attach the two piezoelectric elements to the palm and the wrist.

Note that the first piezoelectric element 11 may be arranged at least along the palm region 101 that is the first detection target, and need not be arranged in the wrist region 103.

FIG. 6 is an external perspective view of a glove 5A including a displacement detection sensor 1A according to the first modification. 7A is a plan view of a displacement detection sensor 1A according to Modification 1, FIG. 7B is a cross-sectional view taken along the line AA, and FIG. 7C is a bottom view. .

The displacement detection sensor 1A has a shorter length in the longitudinal direction of the first piezoelectric element 11 than the displacement detection sensor 1. The first piezoelectric element 11 is arranged along the palm region 101, and is not arranged in the wrist joint region 102 and the wrist region 103. Other structures are the same as the structures shown in FIGS. 1, 2A, 2B, and 2C.

In this case, the first piezoelectric element 11 has high sensitivity to the movement of the palm and low sensitivity to the movement of the wrist and the wrist joint. Therefore, the displacement detection sensor 1A can detect the movement of the palm with high sensitivity without detecting the movement when the wrist joint is bent.

8A is a plan view of a displacement detection sensor 1B according to Modification 2, FIG. 8B is a cross-sectional view taken along the line AA, and FIG. 8C is a bottom view. . The same configurations as those in FIGS. 7A, 7B, and 7C are denoted by the same reference numerals, and description thereof will be omitted. The base material 10 of the displacement detection sensor 1B includes a slit 90. The slit 90 has a rectangular shape in plan view. The slit 90 is formed along the lateral direction near the center of the base material 10 in the longitudinal direction. The slit 90 is arranged in the area 102 of the wrist.

In this case, even if the portion where the first piezoelectric element 11 is not arranged is bent, the expansion and contraction of the base material 10 is blocked by the slit 90. In other words, the bending displacement of the portion caused by the movement of the wrist and the joint of the wrist is blocked by the slit 90 and is not transmitted to the portion where the first piezoelectric element 11 is arranged. Therefore, the displacement detection sensor 1B does not detect the voltage in the first piezoelectric element 11 due to the movement of the joint even when the displacement detection sensor 1B is arranged across a site having a large bending displacement such as a wrist joint.

Also, the portion of the base material 10 where the slit 90 is formed is easier to bend than the other portions. That is, the portion of the base material 10 where the slit 90 is formed is a stress relaxation portion. Therefore, even if the displacement detection sensor 1B is arranged across a large displacement such as a wrist joint, stress is not concentrated on the displacement detection sensor 1B. Therefore, it is possible to reduce the risk that the displacement detection sensor 1B will be peeled off from the globe or the fixed position of the globe will be changed.

The stress relaxation portion is not limited to the slit 90, and may be a notch or a recess, for example. Further, the second piezoelectric elements 12 of the displacement detection sensor 1A and the displacement detection sensor 1B are arranged from the palm to the wrist, but the second piezoelectric element 12 extends at least along the region 103 of the wrist which is the second detection target. However, it is not necessary to arrange along the palm region 101.

FIG. 9A is a plan view of a displacement detection sensor 1C according to Modification 3, and FIG. 9B is a sectional view (a sectional view taken along the line AA).

In the

displacement detection sensors

1, 1A, 1B, the first piezoelectric element 11 and the second piezoelectric element 12 were arranged so as to overlap each other when the base material 10 was viewed in plan. On the other hand, in the displacement detection sensor 1C according to Modification 3, the first piezoelectric element 11 and the second piezoelectric element 12 are arranged so as to be separated from each other when the base material 10 is viewed in a plan view. Further, the first piezoelectric element 11 and the second piezoelectric element 12 are arranged on the same main surface (first main surface) of the base material 10.

Also in this case, the first piezoelectric element 11 has a high sensitivity to the movement of the palm and a low sensitivity to the movement of the wrist and the wrist joint. In addition, the second piezoelectric element 12 has high sensitivity to the movement of twisting of the wrist and low sensitivity to the movement of the palm.

Therefore, the displacement detection sensor 1C can detect the movement of the user's hand and the movement of the wrist individually and with higher accuracy.

Further, between the portion where the first piezoelectric element 11 is arranged and the portion where the second piezoelectric element 12 is arranged in the base material 10, there is a stress relaxation portion 95 that is easier to bend than other portions. The stress relaxation portion 95 is arranged in the joint region 102 of the wrist similarly to the slit 90 of the second modification. In addition, the displacement detection sensor 1C can detect the motion with high accuracy by providing a slit, a notch, or a recess in the stress relaxation portion 95 of the base material 10 to more accurately separate the motion.

Therefore, even if the displacement detection sensor 1C is arranged across a large displacement such as a wrist joint, stress is not concentrated on the displacement detection sensor 1C. Therefore, the possibility that the displacement detection sensor 1C is peeled off from the glove or the fixed position with respect to the glove is reduced.

The area of the first piezoelectric element 11 or the second piezoelectric element 12 and the output are in a proportional relationship. For this reason, the area of the first piezoelectric element 11 or the second piezoelectric element 12 is set to be large at a portion having a small deformation amount, and the area of the first piezoelectric element 11 or the second piezoelectric element 12 is set to be small for a large deformation amount. By devising such a device, the displacement detection sensor 1C can be adjusted to a more appropriate output level, and the circuit design of the displacement detection sensor 1C can be simplified. For example, when the displacement detection sensor 1C is attached to the sole of the shoe, the displacement detection sensor 1C can detect the amount of bending of the sole and the amount of twist of the sole in the left and right directions. The amount of bending of the sole is larger than the amount of twist of the sole, and the signal from the first piezoelectric element 11 or the second piezoelectric element 12 is output in a form according to the amount of deformation. By adjusting the sizes of the first piezoelectric element 11 and the second piezoelectric element 12, respectively, the output levels of the first piezoelectric element 11 and the second piezoelectric element 12 can be made equal, and the displacement detection sensor 1C can be designed with a circuit design. Can be simplified.

Also, when a piezoelectric film is used as the first piezoelectric element 11 or the second piezoelectric element 12, for example, by forming one or a plurality of slits in the piezoelectric film, the apparent stretchability of the piezoelectric film is increased. For this reason, the displacement detection sensor 1C can detect the deformation of a portion having a higher elongation rate as well.

FIG. 10 is a perspective view of a glove 5D including a displacement detection sensor 1D according to Modification 4, and FIG. 11 is a plan view of the displacement detection sensor 1D according to Modification 4. The base material 10 of the displacement detection sensor 1D has a T shape when viewed in a plan view. The displacement detection sensor 1D is also arranged over the palm region 101, the wrist joint region 102, and the wrist region 103. The first piezoelectric element 11 is arranged in the palm area 101, and the second piezoelectric element 12 is arranged in the wrist area 103. The portion serving as the stress relaxation portion is arranged in the wrist joint region 102.

The first piezoelectric element 11 and the second piezoelectric element 12 are arranged so that their longitudinal directions are orthogonal to each other when seen in a plan view. The first piezoelectric element 11 is arranged along the direction in which the fingers are arranged. In this case, the first piezoelectric element 11 has a low sensitivity to displacement in the longitudinal direction of the finger and a high sensitivity to displacement in the direction orthogonal to the longitudinal direction. Therefore, the displacement detection sensor 1D is less sensitive than the

displacement detection sensors

1, 1A, 1B, 1C to the action of grasping the hand and the action of opening the hand. On the other hand, when an operation of pushing the palm out to the front in water is performed, the first piezoelectric element 11 is displaced along the depression of the palm due to the water pressure, and therefore the action of pushing out the water is detected with high accuracy. can do. Therefore, the displacement detection sensor 1D can individually detect the operation of pushing out water and the operation of twisting the wrist with high sensitivity.

In addition, in the present embodiment, the displacement detection sensor is arranged across the palm and the wrist, and an example in which the movement of the hand and the movement of the wrist are individually detected with high sensitivity has been shown. You may arrange | position over the location with large displacement. The displacement detection sensor may be disposed, for example, across the joint of the ankle, and may detect the movement of the foot and the ankle. For example, when the displacement detection sensor is arranged on the sole of the foot, it is possible to detect the bent angle of the sole of the foot or the lateral inclination of the foot during walking. In this case, the displacement detection sensor can be used for a walking tool for rehabilitation. The displacement detection sensor can detect the state of the sole of the foot, and by cooperating with another walking assist robot or the like, a higher rehabilitation effect can be obtained.

Also, the displacement detection sensor can be attached to something other than a human body such as a robot. In this case as well, the displacement detection sensor is arranged so as to straddle a portion where the displacement is large, and detects each individual movement.

In this embodiment, the piezoelectric sensor is shown as the sensor for detecting the bending displacement and the torsional displacement, but the bending displacement and the torsional displacement can be detected even with the strain sensor, for example.

Finally, the description of the above embodiments is to be considered as illustrative in all points and not restrictive. The scope of the invention is indicated by the claims rather than the embodiments described above. Further, the scope of the present invention includes the scope equivalent to the claims.

1, 1A, 1B, 1C, 1D ...

Displacement detection sensors

5, 5A, 5D ... Globe 10 ... Base material 11 ... First piezoelectric element 12 ... Second piezoelectric element 50 ... First protective layer 51 ... Conductive thin film member 52 ... Intermediate layer 53 ... Detection electrode 54 ... Piezoelectric film 55 ... Second protective layer 90 ... Slit 95 ... Stress relaxation portion

Claims

A base material arranged on the first detection target and the second detection target;
A first detector that detects displacement in a first direction;
A second detector for detecting a displacement in a second direction different from the first direction;
Equipped with
The first detection unit and the second detection unit are arranged on the base material,
The first detection unit is arranged at least in the first detection target,
The second detection unit is arranged at least in the second detection target,
Displacement detection sensor.
The first detection unit and the second detection unit are arranged so as to overlap each other in a plan view of the base material.
The displacement detection sensor according to claim 1.
The first detection unit is disposed on the first main surface of the base material,
The second detector is disposed on the second main surface of the base material,
The displacement detection sensor according to claim 1.
The first detection unit and the second detection unit are arranged so as to be separated from each other in a plan view of the base material.
The displacement detection sensor according to claim 1.
In the base material, a stress relaxation portion is arranged between a portion arranged on the first detection target and a portion arranged on the second detection target,
The displacement detection sensor according to any one of claims 1 to 4.
The first detection unit and the second detection unit each have a piezoelectric film,
The displacement detection sensor according to any one of claims 1 to 5.
When the base material is bent, a neutral surface that does not expand and contract exists in a portion other than the piezoelectric film.
The displacement detection sensor according to claim 6.