JP2000227371A - Face pressure distribution detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a face pressure detector having an inexpensive pressure detecting section which can be maintained easily while prolonging the service life. SOLUTION: A pressure detecting section 1 comprises a plurality of elastic balls of identical diameter made of the same material or a plate having ball-like protrusions of identical diameter made of an elastic material. When an object to be measured, e.g. a foot 7, is placed on the pressure detecting section 1 through a light shielding sheet 3, a compressed surface appears at the part touching a glass 2 because of the elasticity of the ball. Difference in the size of the compressed surface between respective balls is picked up as an image of an illuminator 4 having different reflectance by means of an image pick-up unit 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for detecting and measuring the distribution of pressure applied to the sole of a person's foot, that is, the distribution of foot pressure, and more particularly to a device for detecting surface pressure distribution.

[0002]

2. Description of the Related Art Heretofore, as this type of surface pressure distribution detecting device, there has been known a system shown in FIG. 8 in which strain gauges are arranged in a matrix and each output is taken in from rows and columns. And Japanese Patent No. 2750583).

[0003]

In the prior art described above, the number of wirings for extracting the output of the strain gauge is increased, and the weight is repeatedly applied to the wiring, so that the connection point may be damaged or disconnected. May happen,
This takes time to maintain. Further, when the whole is replaced, there is a problem that maintenance cost becomes expensive.

The present invention has been made in view of the above-mentioned problems of the prior art, and an object of the present invention is to eliminate a complicated manufacturing process by eliminating wiring for a pressure detecting portion. At the same time, it is an object of the present invention to eliminate maintenance work related to wiring and to provide a surface pressure distribution detecting device of uniform quality at low cost.

[0005]

In order to achieve the above object, a surface pressure distribution detecting device according to the present invention, when a load is applied to a rubber ball, is in contact with the floor on which the ball is placed. The part is compressed and flattened. The pressure is to be known from the correlation between the compression surface of the flattened ball and the load.

A ball of the same material and the same diameter is placed on a transparent or frosted glass at a constant interval, and when a person stands on the ball, the load received by each ball is different due to the difference in pressure of each part of the sole surface. . At this time, the distribution of foot pressure can be determined by examining the area of the compressed surface of each ball in contact with the frosted glass.

For the same purpose, instead of using individual balls, use is made of an integrally molded sheet-like one in which a plurality of hemispherical balls are projected from a sufficiently soft plate. Then, it can be handled as one component.

Further, depending on the selection of the material, it is possible to use a ball having a small diameter. Thereby, the resolution of the distribution can be improved.

The shape of the projection can be not only a hemisphere but also a cone, a triangular pyramid, a quadrangular pyramid, or a pentagonal pyramid. Depending on the shape, the correlation curve between the compression surface and the weight can be devised.

When the compression surface of the ball is photographed by the photographing device from the back surface of the glass, it can be understood as the difference in the reflectance of the light of the illumination device between the place where the ball has the compression face and the place where the ball does not exist. At this time, it is necessary to prevent light from entering from the surface of the glass. Also, rather than transparent glass,
The use of the frosted glass treated on the lighting device side allows the compression surface to be captured with relatively little restriction on the reflection angle of the lighting.

If the image is captured by a computer using a television camera as a photographing device and then binarized and the area of the compressed surface is treated as the number of pixels, the size of the compressed surface can be digitally quantified. The detection process can be performed by a computer.

Further, by dividing the photographed screen into square blocks, each of which is several times larger than the diameter of the compression surface, the distribution of the surface pressure can be sampled and displayed as a mosaic image. This sampling process enables the use of linear or lattice-shaped (each line or each lattice has a semicircular or triangular cross section) projection sheet even if the adjacent compressed surfaces are attached to each other.

[0013]

Embodiments of the present invention will be described with reference to the drawings. 1 to 5, a sheet glass (2), a plurality of resilient pressure detecting members (1) made of the same material on which an object to be measured is placed, and a glass (2). A) a lighting device (4) arranged below the lower surface, and also a position below the lower surface of the glass (2) to receive the light reflection of the lighting device (4), A surface pressure distribution detecting device including an imaging device (5) for capturing a compressed surface of a pressure detecting member (1) in contact with an upper surface from a lower surface of a sheet glass (2). The pressure detecting section 1 is formed of a resilient material such as silicone rubber or urethane rubber, and is formed in a ball shape or a sheet shape with protrusions. 1 and 2 are a perspective view and a cross-sectional view when the pressure detection unit 1 is implemented with a ball. More specifically, FIG. 3 shows a side view when the pressure detecting unit 1 is formed integrally with a hemispherical sheet with protrusions, and FIG.
FIG. 3 is a side view showing a case where the pressure detecting unit 1 is integrally formed with a protruding sheet such as a cone, a triangular pyramid, a quadrangular pyramid or a pentagonal pyramid.
In the example of the foot pressure distribution detecting device of FIG.
There is a flexible light-shielding sheet 3 above and a hard glass 2 below. Below the hard glass 2, a lighting device 4 and a photographing device 5 are arranged symmetrically. Case 6
Also serves as an external light shield. The foot 7, which is the object to be detected,
It will ride on the light shielding sheet 3.

At this time, in FIG. 5, the compression surface a of the pressure detection unit 1 in the portion A to which a stronger pressure is applied is larger than the compression surface b of the pressure detection unit 1 in the portion B to which a weaker pressure is applied.

The compression surface obtained in this manner is captured as an image by the photographing device 5 by utilizing the difference in the reflectance of light when the light of the illumination device 4 is applied to the hard glass 2.

Thus, if the obtained image is taken into a computer and then binarized and the area of the compressed surface is treated as the number of pixels, the size of the compressed surface can be digitally quantified. Thereby, the distribution state of the foot pressure can be grasped numerically.

Further, as shown in FIG. 6, by dividing the photographing screen into square blocks whose size is several times larger than the diameter of the compression surface, the distribution of the pressure of the foot 7 can be sampled and displayed as a mosaic image. 7 can be converted to a brightness difference.

FIG. 7 shows an example of a system in which the output of the foot pressure distribution detecting device 8 is taken into a computer 10 via a cable 9, converted into a brightness difference, and the distribution state is visually displayed on a monitor 11. Show.

[0019]

Since the present invention is configured as described above, the following effects can be obtained.

In a surface pressure detecting device, a compressed surface, which is a detection output, can be captured as an image by using a photographing device such as a television camera. Therefore, there is no need to worry about wire breakage or breakage due to the repeated pressure of the object to be detected, as compared with the strain gauge matrix system in which the output is taken in via an electric wire as shown in FIG. In addition, maintenance is relatively inexpensive because only the sheet with protrusions is replaced.

[Brief description of the drawings]

FIG. 1 is a perspective view of a main part of a foot pressure distribution detecting device.

FIG. 2 is a sectional view of a foot pressure distribution detecting device.

FIG. 3 is a side view of a hemispherical pressure detecting unit with a projection.

FIG. 4 is a side view of a projection-like pressure detecting unit having a conical, triangular pyramid, quadrangular pyramid, or pentagonal pyramid shape;

FIG. 5 is an explanatory diagram of a correlation between a compression surface of a ball and a weight.

FIG. 6 is an explanatory diagram of lightness difference conversion by sampling a binarized image of a pressure surface.

FIG. 7 is a schematic diagram of a foot pressure distribution visual display system.

FIG. 8 is a circuit diagram of a strain gauge matrix system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pressure detection part 2 Hard glass 3 Light shielding sheet 4 Illumination device 5 Imaging device 6 Case 7 Feet 8 Foot pressure distribution detection device 9 Cable 10 Computer 11 Monitor 12 Strain gauge matrix type surface pressure distribution detection part A Strong pressure application part B Low pressure Applying part a High pressure compression surface b Low pressure compression surface M Strain gauge X1, X2, X3, XN Row direction wire Y1, Y2, Y3, YN Column direction wire

Claims (1)

[Claims] 1. A sheet glass (2), a plurality of resilient pressure detecting members (1) made of the same material on which an object to be measured placed on the glass (2) is placed, and a lower surface of the glass (2) And a lighting device (4) arranged below the lower surface of the glass (2), and also positioned below the lower surface of the glass (2) to receive the reflection of light of the lighting device (4), and disposed on the upper surface of the sheet glass (2). A surface pressure distribution detecting device including an imaging device (5) for capturing a compression surface of a pressure detecting member (1) in contact with the lower surface of a glass sheet (2).