JP2001321358A - Displacement sensor for organism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a displacement sensor for organism capable of measuring a bending angle even in the freely movable state of a joint part or the like and measuring the bending angle in a wide range without causing an obstruction such as movement of the joint part or the like. SOLUTION: This sensor is formed of a flexible plate member 11 having a strain gauge 13 in the center and mounting parts 17 mountable on organism on both ends thereof. A bellows-like easily deformable part 12 is provided between the strain gauge 13 and each mounting part 17.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a displacement sensor for a living body, and more particularly, to a displacement sensor for a living body for measuring a bending angle of a joint in real time.

[0002]

2. Description of the Related Art A goniometer according to the technique disclosed in Japanese Utility Model Laid-Open No. 5-76403 is used as an apparatus for measuring the angle of bending of a joint of a living limb.
By attaching this to a joint and measuring the angle of the limb, it is used for diagnosis of the degree of recovery of a patient during rehabilitation.

[0003] In recent years, in research on rehabilitation, sports, and the like, real-time measurement of the movement of joints and the like and measurement of the wrist movement of a medical worker performing an operation in real time have been used to realize virtual reality by a computer. It is becoming possible to realize the display using. For this purpose, a device for measuring the angle of a joint or the like in real time is required.

However, in applications where it is necessary to measure the angle of rotation in real time while constantly moving a joint or the like, the above-described goniometer cannot move the joint sufficiently, and it is difficult to move the joint at high speed. It cannot follow in real time.

[0005] For this reason, it is conceivable to use a displacement sensor for a living body as the eyelash angle measuring device suitable for the above-mentioned application. With this displacement sensor for living body, a strain gauge is attached to a plate-like member, and both ends of the plate-like member are attached to a joint, so that the bending angle can be measured even when the joint can freely move. Device.

FIG. 7 is an overall perspective view of a conventional displacement sensor for a living body. As shown in FIG.
Reference numeral 0 denotes a structure in which the plate-like member 21 has a curved portion 22 that is greatly curved, and a curved portion in the curved portion 22 is provided with a strain gauge 23 to which output lead wires 24a and 24b that are electrically connected are attached. It has become.

In this structure, when a strain gauge is attached to a mere flat plate-like member, the strain becomes too large even with a small angle of bending, and the output voltage value of the strain gauge is saturated, and the strain gauge itself is damaged. In order to avoid such problems as described above, such a large curved portion is provided.

[0008]

However, since the conventional displacement sensor for a living body as described above has a structure in which the plate-like member is greatly curved, when the sensor is attached to a joint or the like of a living body, the curved member has a curved shape. The portion protrudes, which becomes an obstacle when moving the joints and the like, and restricts the operation. For example,
When worn on the wrist of a medical worker performing surgery, there arises a problem that free work cannot be performed.

The present invention has been made in view of the above-mentioned conventional problems and circumstances, and it is possible to measure a bending angle even in a state where the joints and the like can freely move, and to prevent obstacles when moving the joints and the like. It is an object of the present invention to provide a displacement sensor for a living body that can measure a wide range of angle without causing the displacement.

[0010]

According to a first aspect of the present invention, there is provided a displacement sensor for a living body having a flexible plate-like member provided with a strain gauge, and a living body at both ends of the plate-like member. In the displacement sensor for a living body having a mounting portion that can be mounted on, by providing the plate-shaped member with the easily deformable portion, the easily deformable portion absorbs the displacement of the plate-shaped member due to bending of the mounted living body to a certain extent, It is possible to widen the measurement range of the angle.

According to a second aspect of the present invention, in the displacement sensor for a living body, since the easily deformable portion is provided both before and after the strain gauge, a larger displacement can be easily deformed than when only one side is provided. Because the part can absorb, it is possible to measure a wider range of angle of birth.

According to a third aspect of the present invention, in the displacement sensor for a living body, since the easily deformable portion is formed in a bellows shape, the bellows absorbs to some extent the displacement of the plate-like member due to bending of the mounted living body, and furthermore, the bellows Since the plate-shaped member is folded in the shape of a circle, the effective length of the plate-shaped member can be lengthened, so that a wider range of angle can be measured.

According to a fourth aspect of the present invention, there is provided the displacement sensor for a living body, wherein the easily deformable portion is configured to be narrower than the other portion of the plate-like member. Can be expanded to a certain extent by the part configured to be narrow, so that the measurement range of the angle of the bend can be widened.

According to a fifth aspect of the present invention, in the displacement sensor for a living body, since the easily deformable portion is formed thinner than other portions of the plate-like member, displacement of the plate-like member due to bending of the mounted living body is reduced. The absorption range can be widened by absorbing the thinly configured part to some extent.

According to a sixth aspect of the present invention, in the displacement sensor for a living body, the mounting portion is configured to be rotatable along at least a plane orthogonal to a thickness direction of the plate-shaped member, so that a measuring point can be freely set. It is possible to reduce the influence of the bending motion other than the thickness direction of the plate-shaped member, which is the measurement direction, without hindering the movement.

According to a seventh aspect of the present invention, in the displacement sensor for a living body, since the plate-shaped member is made of a synthetic resin, it is made of a material which is easy to be dazzled, is easily processed, and the easily deformable portion is easily formed. .

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the displacement sensor for living body according to the present invention will be described below in detail with reference to the drawings. (First Embodiment) FIG. 1 is an overall perspective view showing a first embodiment of a biological displacement sensor according to the present invention. As shown in FIG. 1, a biological displacement sensor 10 according to the present embodiment
Has a structure in which a flexible plate-shaped member 11 having a strain gauge 13 at the center thereof is provided, and mounting portions 17 that can be mounted on a living body are provided at both ends of the plate-shaped member 11. The plate-shaped member 11 has an easily deformable portion 12.

As shown in FIG. 1, the easily deformable portion 12
By being formed in a bellows shape, the structure is easily deformed. This allows the easily deformable portion to absorb to some extent the displacement of the plate-like member due to bending of the mounted living body,
It is possible to widen the measurement range of the angle. In addition, the length that can be attached is limited in a joint part of a living body or the like. However, a length longer than the limit can be realized by folding the plate-shaped member 11 with bellows.

Although the easily deformable portion 12 is provided between the strain gauge 13 and the mounting portions 17 on both sides in FIG. 1, it may be provided on only one side.

The plate-like member 11 can be formed of a material such as plastic, but it is preferable to use, for example, a synthetic resin such as polycarbonate or acrylic.

The strain gauge 13 is capable of detecting a vertical bending angle with respect to the longitudinal direction. When the plate-like member 11 expands and contracts in the longitudinal direction, a strain is generated, and the resistance provided in the strain gauge 13 is increased. The resistance value of the bridge circuit pattern changes.

The output terminals of the resistance bridge circuit pattern of the strain gauge 13 are provided with output lead wires 14a and 14b which are electrically connected using solder or the like. Then, these two output leads 14a and 14b are connected to a device (not shown) required for electrical measurement such as a power supply, a voltage amplifier, and a voltmeter, and a voltage change between the two output leads is measured. The part attached to the living body (joint, etc.)
Can be detected.

The mounting portion 17 is configured to be rotatable along at least a plane orthogonal to the thickness direction of the plate-shaped member 11. For example, as shown in the cross-sectional view of the mounting portion in FIG. 5, the sensor-side fitting member 15 and the living body-side fitting member 16 attached to the plate-like member 11 with an adhesive or the like have a cylindrical fitting portion. By pushing 15a into the living body side fitting member 16,
It has a fitting structure, and can freely rotate in the horizontal direction in the figure. The fitting portion 15a may have another shape such as a spherical shape as long as it is rotatable.

As a method of fixing the mounting portion 17 to the living body, a method of directly bonding to the living body using an adhesive gel or the like, a method of sewing on clothes or the like, a method of applying an adhesive to rubber gloves, and the like are used. be able to.

FIG. 2 is an external view showing a state in which the living body displacement sensor 10 of the present embodiment is actually mounted on a wrist. FIG.
As shown in (1), one mounting portion of the living body displacement sensor is fixed to the back of the hand and the other mounting portion is fixed to the wrist portion by using an adhesive gel or the like.

The mounting position of the biological displacement sensor 10 is as follows.
This is a position for measuring the angle at which the wrist is tilted up and down, and as shown by the arrow in the figure, since the mounting portion freely rotates in the horizontal direction, the displacement of the brow angle that the wrist is swung right and left is not detected. . If the user wants to measure the angle of the wrist swung right and left, the living body displacement sensor 10 is attached to the side surface of the wrist (not shown), so that only the angle of the swung right and left can be detected.

Next, a comparison between the displacement sensor for living body of the present embodiment and a sensor in which a strain gauge is attached to a flat plate member (not bent at all) is attached to the wrist as shown in FIG. FIG. 6 is a graph showing the correspondence between the bristles angle of the wrist and the change of the output voltage in the case of wearing.

In FIG. 6, the horizontal axis of the graph is the wrist angle, and the vertical axis is the voltage change value (V) measured by an external measuring device. This voltage change value (V) was measured at an amplification factor of 5,000 and a bridge voltage of 1 V.

As is apparent from this graph, the displacement sensor for a living body having the same length using a flat plastic plate as a plate-shaped member saturates the output voltage at a bend angle of 30 degrees or less, making measurement impossible. On the other hand, the displacement sensor for a living body according to the present embodiment was able to measure up to 100 degrees of the bald angle. This is because the effective length of the plate member can be increased by folding the plate member with bellows.

(Second Embodiment) FIG. 3 is a perspective view of a main part of a displacement sensor for living body according to a second embodiment of the present invention. As shown in FIG. 3, in the present embodiment, the easily deformable portion 1 configured to be narrower than other portions of the plate-like member 11 is provided.
2 is provided. The other components are configured in the same manner as in the first embodiment.

(Third Embodiment) FIG. 4 is a sectional view of a main part of a displacement sensor for living body according to a third embodiment of the present invention. As shown in FIG. 4, in the present embodiment, the easily deformable portion 1 is configured to be thinner than other portions of the plate-shaped member 11.
2 is provided. The other components are configured in the same manner as in the first embodiment.

[0032]

As described above in detail, according to the displacement sensor for living body according to the first aspect of the present invention, a flexible plate-shaped member having a strain gauge is provided, and both ends thereof can be attached to a living body. By providing the plate member with the easily deformable portion, the displacement of the plate member due to bending of the attached living body is absorbed to some extent by the easy deformable portion, so that the measurement range of the bending angle can be widened. Provided is a displacement sensor for a living body that can measure a bending angle even when a joint or the like can freely move, and can measure a wide range of the bending angle without causing an obstacle when moving the joint or the like. Can be done.

According to the displacement sensor for living body of the present invention, since the easily deformable portion is provided both before and after the strain gauge, a larger displacement can be provided than when only one side is provided. By absorbing the easily deformable portion, it is possible to measure a wider range of the angle of bending.

According to the displacement sensor for a living body according to the third aspect, since the easily deformable portion is formed in a bellows shape, the bellows absorbs the displacement of the plate-like member due to the bending of the mounted living body to a certain extent. Since the plate-like member is folded in a bellows shape, the effective length of the plate-like member can be increased, so that a wider range of angle can be measured.

According to the displacement sensor for a living body of the fourth aspect, since the easily deformable portion is configured to be narrower than the other portion of the plate-like member, the plate-like member caused by bending of the mounted living body. The displacement of the angle can be absorbed to some extent by the portion configured to be narrow, so that the measurement range of the bending angle can be widened.

According to the displacement sensor for a living body of the fifth aspect, the easily deformable portion is formed thinner than the other portion of the plate-like member. By absorbing the displacement to a certain extent by the thinly configured portion, the range of measurement of the angle of bending can be widened.

According to the displacement sensor for living body of the sixth aspect, the mounting portion is rotatable along at least a plane orthogonal to the thickness direction of the plate-shaped member, so that the measuring portion can be provided at the measuring point. The effect (noise) due to the bending motion other than the thickness direction of the plate-shaped member, which is the measurement direction, can be suppressed without hindering the free movement. In addition, with this configuration, there are a method of directly bonding the mounting portion to the living body using an adhesive gel, a method of sewing the mounting portion to clothes, a method of applying an adhesive to a rubber glove, and a method of bonding the mounting portion. Can respond.

In the displacement sensor for a living body according to the seventh aspect, since the plate-shaped member is made of a synthetic resin and is made of a material that is easy to bend, the free movement of the living body is not hindered. Further, processing is easy, and formation of the easily deformable portion is easy. Furthermore, it can be manufactured at low cost.

As described above, the living body displacement sensor of the present invention measures the movement of a joint or the like in real time in research on rehabilitation, sports, and the like, and measures the movement of the wrist of a medical worker performing surgery in real time. Such,
An object of the present invention is to provide a displacement sensor for a living body suitable for measuring a bending angle when performing display using virtual reality by a computer.

[Brief description of the drawings]

FIG. 1 is an overall perspective view showing a first embodiment of a biological displacement sensor according to the present invention.

FIG. 2 is an external view illustrating a state where the biological displacement sensor of FIG. 1 is actually mounted on a wrist.

FIG. 3 is a perspective view of a main part showing a second embodiment of the displacement sensor for a living body according to the present invention.

FIG. 4 is a cross-sectional view of a main part showing a third embodiment of the displacement sensor for living body according to the present invention.

FIG. 5 is a sectional view of a mounting portion of the displacement sensor for living body according to the present invention.

FIG. 6 shows the wrist angle measured in the state of FIG.
6 is a graph showing a correspondence with a change in output voltage.

FIG. 7 is an overall perspective view of a conventional displacement sensor for living body.

[Explanation of symbols]

 REFERENCE SIGNS LIST 11 plate member 12 easily deformable portion 13 strain gauge 14 a, 14 b output lead wire 15 a fitting portion 15 sensor side fitting member 16 living body side fitting member 17 mounting portion 20 displacement sensor 21 for living body 21 plate member 22 curved portion 23 distortion Gauge 24a, 24b Output lead wire

Continued on the front page F term (reference) 2F063 AA33 BA29 DA02 DA05 EC00 LA27 2F077 AA49 CC02 EE07 VV02 VV33 4C038 VA03 VB12 VB14 VC20

Claims (7)

[Claims] 1. A living body displacement sensor having a flexible plate-shaped member provided with a strain gauge and having mounting portions that can be mounted on a living body at both ends of the plate-shaped member, wherein the plate-shaped member has an easily deformable portion. A displacement sensor for a living body, comprising: 2. The displacement sensor for a living body according to claim 1, wherein the easily deformable portion is provided both before and after the strain gauge. 3. The displacement sensor for a living body according to claim 2, wherein the easily deformable portion is formed in a bellows shape. 4. The biological displacement sensor according to claim 2, wherein the easily deformable portion is configured to be narrower than other portions of the plate-shaped member. 5. The displacement sensor for a living body according to claim 2, wherein the easily deformable portion is configured to be thinner than other portions of the plate-shaped member. 6. The displacement sensor for a living body according to claim 1, wherein the mounting portion is configured to be rotatable along a plane at least orthogonal to a thickness direction of the plate-shaped member. A displacement sensor for a living body, comprising: 7. The displacement sensor for a living body according to claim 1, wherein said plate-shaped member is made of a synthetic resin.