JP4997595B2 - Floor reaction force estimation system and floor reaction force estimation method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a system for estimating floor reaction force, capable of being compatible to many people having foots in different sizes, providing comfortable feeling in wearing, and achieving a walking action equivalent to a case where a person wears a normal footwear without a sensor, and to provide a method for estimating a floor reaction force. <P>SOLUTION: This system for estimating floor reaction force is configured of a footwear type floor reaction force measurement device having a flexible sole and an analysis device for analyzing an output of the floor reaction force measurement device. Each of the system and the method is adapted to estimate a floor reaction force according to an output of a force sensor provided in the footwear type floor reaction force measurement device. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a floor reaction force estimation system and a floor reaction force estimation method. More specifically, it is applicable to a large number of people with different foot sizes, provides comfortable comfort, and enables a floor reaction force that can realize walking motion similar to that when wearing normal footwear without sensors. The present invention relates to an estimation system and a floor reaction force estimation method.

  The technique for measuring the load distribution and the load change on the sole can be applied to various fields. For example, the measurement data of the treading pressure during walking of a physically handicapped person wearing a prosthetic leg and a prosthetic limb is useful for the development of the prosthetic leg and the prosthetic limb. Alternatively, the measurement data of the load applied to the sole of the golfer is used for the analysis of the golf swing.

Patent Document 1 proposes an apparatus for acquiring data on the load on such a sole. FIG. 17 is a cross-sectional view of a footwear-type load measuring device proposed by Patent Document 1.
The load measuring device (S) proposed in Patent Document 1 has a shoe shape, a sole part (B) where the ground and the lower surface are grounded, and extends upward from the periphery of the sole part (B). An insole portion (I) disposed in a space surrounded by an upper portion (U) surrounding the upper surface, an upper surface of the sole portion (B) and an inner surface of the upper portion (U), a lower surface of the insole portion (I) and the sole A three-component force sensor (L) is provided between the upper surfaces of the parts (B).
The three component force load sensor (L) is parallel to the force component in the direction perpendicular to the upper surface of the sole portion (B) (ie, the vertical direction) and the upper surface of the sole portion (B). The force component in the front-rear direction of the part (B) and the force component in the left-right direction of the sole part (B) can be measured.

  The load measuring device (S) disclosed in Patent Document 1 uses the three-component force sensor (L) to measure the load applied to the sole, thereby sensing necessary for the conventional load measuring device. It has succeeded in reducing the number of devices, reducing the weight of the load measuring device, and reducing the manufacturing cost.

JP 2005-214850 A

FIG. 18 shows the arrangement of the three-component force sensor (L) in the load measuring device (S) shown in FIG.
The load measuring device (S) disclosed in Patent Literature 1 uses a path of force transmitted from the ground to the sole in order to accurately calculate a force component in a direction orthogonal to the upper surface of the sole portion (B). A three-component force sensor (L) is arranged so as to cover substantially the entire upper surface of the sole portion (B) so as to cross.
As a result, the flexibility of the sole portion (B) is lost. Then, the walking of the subject whose tread pressure is measured while wearing the load measuring device (S) becomes unnatural, and tread pressure data in a walking state different from the normal walking state is generated.

Furthermore, the load measuring device (S) disclosed in Patent Document 1 is a force transmitted from the ground to the sole in order to accurately calculate a force component in a direction orthogonal to the upper surface of the sole portion (B). It is necessary to use a three-component force load sensor (L) arranged so as to cover substantially the entire upper surface of the sole part (B) so as to cross the path of, and the sole is separated from the sole part (B), for example, It is not possible to use footwear of a kind that does not restrain the periphery of the heel such as sandals (that is, does not have an upper portion (U) around the heel).
As a result, the size of the foot applicable to one load measuring device (S) is determined to be one, and it is difficult to target a large number of subjects. Therefore, when there are subjects having different foot sizes, it is necessary to prepare a plurality of load measuring devices (S) having different sizes.

  The present invention has been made in view of the above circumstances, and is applicable to a large number of people with different foot sizes and provides comfortable comfort when wearing normal footwear without a sensor. An object of the present invention is to provide a floor reaction force estimation system and a floor reaction force estimation method capable of realizing the same walking motion.

The invention according to claim 1 is a floor reaction force estimation system comprising a footwear type floor reaction force measuring device having a flexible sole, and an analysis device for analyzing an output of the floor reaction force measuring device. The floor reaction force measuring device includes force sensors at a plurality of locations on the sole, and the force sensor includes at least two force components substantially parallel to the upper surface of the sole and a force component in a direction perpendicular to the upper surface of the sole. Is output to the analysis device, and the analysis device, based on the output information, at least two force components substantially parallel to the upper surface of the sole and a force component in a direction perpendicular to the upper surface of the sole A first step of calculating an estimation coefficient, an estimation coefficient set in advance in the analyzer, a force component in two directions substantially parallel to the calculated upper surface of the sole, and a force component in a direction perpendicular to the upper surface of the sole Calculated value of at least one of them Summing a second step of integrating, the accumulated value, and executes the third step of calculating the floor reaction force, the footwear type floor reaction force measuring device detects an inclination angle of the sole with respect to the ground slope A floor reaction force estimation system comprising an angle detector .
The invention according to claim 2 is based on the relationship between the actual value obtained by directly measuring the floor reaction force and the calculated value obtained by the first step obtained when measuring the actual value. The floor reaction force estimation system according to claim 1, wherein the estimation coefficient is identified so that a difference between a calculated value of the floor reaction force obtained in three steps and the actual measurement value is minimized.

According to a third aspect of the present invention, the inclination angle detector is arranged in a region that exists in front of a portion of the sole that contacts the MP joint and a region that exists in the rear of a portion that contacts the MP joint. The floor reaction force estimation system according to claim 1 .
According to a fourth aspect of the present invention, the inclination angle detector measures a change rate of the inclination angle of the sole upper surface and outputs the change rate to the analysis device, and the analysis device integrates the output change rate of the inclination angle. The floor reaction force estimation system according to claim 1 , wherein the inclination angle of the sole is calculated.
According to a fifth aspect of the present invention, the tilt angle detector measures an angular acceleration of the tilting motion of the sole upper surface and outputs the angular acceleration to the analysis device, and the analysis device integrates the output angular acceleration. The floor reaction force estimation system according to claim 1, wherein an inclination angle of the sole is calculated.
According to a sixth aspect of the present invention, the tilt angle detector is an acceleration sensor, and the acceleration sensor has an acceleration component parallel to the sole upper surface and an acceleration component perpendicular to the sole upper surface. Measure the ratio between the gravitational acceleration acting on the sole and the acceleration component in the parallel direction, the ratio between the gravitational acceleration acting on the sole and the acceleration component in the perpendicular direction, or the ratio between the acceleration component in the parallel direction and the acceleration component in the perpendicular direction The floor reaction force estimation system according to claim 1, wherein an inclination angle of the sole is calculated based on
According to a seventh aspect of the present invention, the analysis device performs a coordinate conversion process on the output of the force sensor based on the inclination angle of the sole obtained by the output from the inclination angle detector, The floor reaction force estimation system according to claim 1, wherein a force component in a parallel direction and a force component in a direction perpendicular to the ground are calculated.
According to an eighth aspect of the present invention, when the calculated values of the force components in the direction perpendicular to the upper surface of the sole obtained in the first step are not all equal to zero, the analysis device causes the entire sole surface to be on the ground. The floor reaction force estimation system according to claim 7, wherein the ground reaction force is determined to be grounded.
According to a ninth aspect of the present invention, when the calculated values of the force components in the direction perpendicular to the sole upper surface obtained in the first step are not all equal to zero, before the state becomes not equal to zero, 5. The floor reaction force estimation system according to claim 4 , wherein the value of the integration calculation of the angular velocity performed by the analyzing device is set to zero and the integration calculation is restarted.

The invention according to claim 10 is the floor reaction force estimation system according to claim 1, wherein the force sensor is a three-component force load sensor.
The invention according to claim 11 is the floor reaction force estimation system according to claim 10 , characterized in that the force sensor is arranged in a heel part, a Chopard joint part, a fourth MP joint part, and a main heel part.
Invention of claim 12, wherein the force sensor is the heel portion, Chopard joint, the 4MP articulation, claim, characterized in that arranged on the base foot portion, the 1MP joint and the third foot portion 10 It is a floor reaction force estimation system of description.
The invention according to claim 13 is the floor reaction force according to claim 11 , wherein the force sensor is further arranged in any one selected from the group consisting of the first MP joint and the third buttocks. It is an estimation system.
According to a fourteenth aspect of the present invention, the three-component force sensor comprises a disc portion, a plurality of leg portions that extend from the disc portion and bend downward, and a strain gauge that is attached to the leg portion. The pair of legs are attached to the upper surface of the sole and extend in one direction parallel to the upper surface of the sole, and the other pair of legs of the legs are the sole extending with mounted on the upper surface in a direction orthogonal to the one direction parallel to the sole top surface, according to claim 10, wherein said disc portion and said leg portion, characterized in that it is formed of a rubber material This is a floor reaction force estimation system.

The invention according to claim 15 is a floor reaction force estimation system comprising a footwear type floor reaction force measuring device having a flexible sole and an analysis device for analyzing an output of the floor reaction force measuring device. The floor reaction force measuring device includes force sensors at a plurality of locations on the sole, and the force sensor includes at least two force components substantially parallel to the upper surface of the sole and a force component in a direction perpendicular to the upper surface of the sole. Is output to the analysis device, and the analysis device, based on the output information, at least two force components substantially parallel to the upper surface of the sole and a force component in a direction perpendicular to the upper surface of the sole A first step of calculating an estimation coefficient, an estimation coefficient set in advance in the analyzer, a force component in two directions substantially parallel to the calculated upper surface of the sole, and a force component in a direction perpendicular to the upper surface of the sole Calculation of at least one of them A second step of integrating the, summing the accumulated value, and executes the third step of calculating the floor reaction force, wherein the force sensor is a piezoelectric polymer sheet sensor having flexibility, a pressure sensor The piezoelectric polymer sheet sensor measures a force component in two directions parallel to the surface of the sole, and the pressure sensor measures a force component in a direction perpendicular to the upper surface of the sole. This is a characteristic floor reaction force estimation system.
A sixteenth aspect of the present invention is the floor reaction force estimation system according to the fifteenth aspect, characterized in that the pressure sensor is arranged in a hip, a Chopard joint, a fourth MP joint, and a main hip.
Invention of claim 17, wherein the pressure sensor is, the heel portion, Chopard joint, the 4MP articulation, claim, characterized in that arranged on the base foot portion, the 1MP joint and the third foot portion 15 It is a floor reaction force estimation system of description.
The invention according to claim 18 is the floor reaction force according to claim 16 , wherein the pressure sensor is further arranged in any one selected from the group consisting of the first MP joint part and the third collar part. It is an estimation system.

The invention according to claim 19 is the floor reaction force estimation system according to claim 15 , wherein the piezoelectric polymer sheet sensor is substantially the same shape and size as the sole.
The invention according to claim 20 is the floor reaction force estimation system according to claim 1, wherein the floor reaction force measuring device does not restrain the periphery of the heel.
The invention according to claim 21 is the floor reaction force estimation system according to claim 1, wherein the load position is further calculated in the third step.

The invention according to claim 22 is based on the relationship between the actual measurement value obtained by directly measuring the floor reaction force and the output value of the force sensor obtained when the actual measurement value is measured. An estimation coefficient identifying step for identifying the estimation coefficient so that a difference between the product of the output value and the actual measurement value is minimized, and a plurality of shoes disposed on the flexible sole of the footwear type floor reaction force measuring device A floor reaction force measuring step for measuring information related to at least two force components substantially parallel to the upper surface of the sole, and information related to a force component in a direction perpendicular to the upper surface of the sole, Based on information related to a force component in two directions substantially parallel to the upper surface of the sole and a force component in a direction perpendicular to the upper surface of the sole, the force component in two directions substantially parallel to the at least the upper surface of the sole; Force component in the direction perpendicular to the upper surface of the sole A first step of taking out, a second step of integrating the estimation coefficient and the force component calculated in the first step, and a third step of calculating the floor reaction force by summing up the integrated values. The floor reaction force estimation method includes a floor reaction force calculation step to be executed, and the floor reaction force measurement step includes a step of measuring an inclination angle of the sole with respect to the ground .

The invention according to claim 23 is based on the relationship between the actual measurement value obtained by directly measuring the floor reaction force and the output value of the force sensor obtained when measuring the actual measurement value. An estimation coefficient identifying step for identifying the estimation coefficient so that a difference between the product of the output value and the actual measurement value is minimized, and a plurality of shoes disposed on the flexible sole of the footwear type floor reaction force measuring device A floor reaction force measuring step for measuring information related to at least two force components substantially parallel to the upper surface of the sole, and information related to a force component in a direction perpendicular to the upper surface of the sole, Based on information related to a force component in two directions substantially parallel to the upper surface of the sole and a force component in a direction perpendicular to the upper surface of the sole, the force component in two directions substantially parallel to the at least the upper surface of the sole; Force component in the direction perpendicular to the upper surface of the sole A first step of taking out, a second step of integrating the estimation coefficient and the force component calculated in the first step, and a third step of calculating the floor reaction force by summing up the integrated values. The floor reaction force measurement step includes the step of measuring the rate of change in the inclination angle of the sole upper surface, the floor reaction force calculation step integrates the measured angular velocity, a floor reaction force estimating how to comprising the step of calculating an inclination angle of the sole.
According to a twenty-fourth aspect of the present invention, an estimation coefficient and the force sensor are calculated from a relationship between an actual measurement value obtained by directly measuring a floor reaction force and an output value of a force sensor obtained when the actual measurement value is measured. An estimation coefficient identifying step for identifying the estimation coefficient so that a difference between the product of the output value and the actual measurement value is minimized, and a plurality of shoes disposed on the flexible sole of the footwear type floor reaction force measuring device A floor reaction force measuring step for measuring information related to at least two force components substantially parallel to the upper surface of the sole, and information related to a force component in a direction perpendicular to the upper surface of the sole, Based on information related to a force component in two directions substantially parallel to the upper surface of the sole and a force component in a direction perpendicular to the upper surface of the sole, the force component in two directions substantially parallel to the at least the upper surface of the sole; Force component in the direction perpendicular to the upper surface of the sole A first step of taking out, a second step of integrating the estimation coefficient and the force component calculated in the first step, and a third step of calculating the floor reaction force by summing up the integrated values. The floor reaction force calculation step includes the step of measuring the angular acceleration of the tilting motion of the upper surface of the sole, and the floor reaction force calculation step integrates the measured angular acceleration. and a floor reaction force estimating how to comprising the step of calculating an inclination angle of the sole.
According to a twenty-fifth aspect of the invention, the step of measuring the inclination angle of the sole with respect to the ground includes an acceleration component parallel to the upper surface of the sole and an acceleration perpendicular to the upper surface of the sole. Measuring the component, and based on the ratio of the gravitational acceleration and the acceleration component in the parallel direction, the ratio of the gravitational acceleration and the acceleration component in the perpendicular direction or the ratio of the acceleration component in the parallel direction and the acceleration component in the perpendicular direction, The floor reaction force estimation method according to claim 22, further comprising a step of calculating an inclination angle.

According to a twenty-sixth aspect of the present invention, in the floor reaction force calculating step, when the output values for the forces perpendicular to the upper surface of the sole from the plurality of force sensors are not all equal to zero, the entire sole surface is against the ground. The floor reaction force estimation method according to any one of claims 22 to 24 , further comprising:
According to a twenty-seventh aspect of the present invention, in the floor reaction force calculating step, when output values for the force in a direction perpendicular to the sole upper surface from the plurality of force sensors are not all equal to zero, the state is not equal to zero. The floor reaction force estimation method according to claim 23 or 24 , further comprising a step of setting an integral value that has been performed before the value becomes equal to zero.
In the invention according to claim 28 , the floor reaction force calculating step performs coordinate conversion based on the measured inclination angle of the sole, and a force in a direction perpendicular to the ground is parallel to the ground. 23. The floor reaction force estimation method according to claim 22 , further comprising a step of calculating a directional force.

The invention of claim 29, wherein the information related to the perpendicular force component with respect to said sole upper surface, a heel portion, Chopard joint, the 4MP joint, characterized in that it is measured in the mother toes claims Item 25. The floor reaction force estimation method according to any one of Items 22 to 24 .
According to a thirty- third aspect of the present invention, the information related to the force component in the direction perpendicular to the upper surface of the sole includes the heel part, the Chopard joint part, the fourth MP joint part, the main heel part, the first MP joint part, and the third heel part. The floor reaction force estimation method according to any one of claims 22 to 24, wherein the floor reaction force estimation method is performed in step (a).
In the invention according to Claim 31 , the information related to the force component in the direction perpendicular to the upper surface of the sole is further measured in any one selected from the group consisting of the first MP joint and the third buttocks. 30. The floor reaction force estimation method according to claim 29 .

The invention according to claim 32 is the floor reaction force estimation method according to any one of claims 22 to 24 , wherein the estimation coefficient identification step is executed for each subject, and the estimation coefficient is determined for each subject. is there.
The invention according to claim 33 further includes a step of preparing a plurality of the footwear type floor reaction force measuring devices, and the estimation coefficient identifying step is executed for each of the prepared footwear type floor reaction force measuring devices. The floor reaction force estimation method according to any one of claims 22 to 24 , wherein the estimation coefficient is determined for each footwear type floor reaction force measuring device.
The invention according to claim 34 is the floor reaction force estimation method according to any one of claims 22 to 24 , wherein a load position is further calculated in the third step.

According to the first aspect of the present invention, since the floor reaction force is calculated using a preset estimation coefficient, the number of floor reaction force sensors that need to be mounted on the footwear type floor reaction force measuring device is reduced. It becomes possible. Therefore, it is possible to secure the flexibility of the sole of the footwear type floor reaction force measuring device attached to the subject and to minimize the adverse effect on the comfort caused by the arrangement of the floor reaction force sensor. In addition, since it is possible to estimate the treading pressure with the force applied to a part of the sole, there is no need to provide a floor reaction force sensor on the entire sole. Applicable to force measuring device. As a result, the same floor reaction force measuring device can be attached to a plurality of subjects having different foot sizes, and suitable data sampling can be performed with a single device for many subjects.
According to the second aspect of the present invention, the estimation coefficient is set so that the difference between the actually measured value obtained by directly measuring the floor reaction force and the estimated value calculated from the output value of the floor reaction force sensor is minimized. Since it is identified, the error between the estimated value and the true value can be minimized.

According to the first and second aspects of the invention, the force component in the direction perpendicular to the upper surface of the sole and the force component in the direction parallel to the upper surface of the sole regardless of the tilting motion of the foot during the walking motion of the subject. Can be estimated.
According to the third aspect of the present invention, it is possible to estimate the force component in the direction perpendicular to the sole upper surface and the force component in the direction parallel to the sole upper surface regardless of the bending of the foot during the walking motion. It becomes possible.
According to the inventions described in claims 4, 5, 23, and 24, it is possible to suitably calculate the inclination angle of the foot.
According to the inventions of claims 6 and 7 and claims 25 and 28 , the force component perpendicular to the ground is parallel to the ground regardless of the tilting motion of the foot during the walking motion of the subject. It becomes possible to estimate the force component in the direction.
According to the inventions of claims 8 and 26, it is possible to reliably determine the state where the entire sole of the foot during the walking motion is in contact with the ground, and the relationship between the state of the foot during the walking motion and the tread pressure fluctuation is preferable. Can be determined.
According to the ninth and twenty-seventh aspects, it is possible to remove the integration error and improve the accuracy of the calculated tilt angle.

According to the tenth aspect of the present invention, the output of the force sensor in the direction perpendicular to the upper surface of the sole and the force component in the two directions parallel to the upper surface of the sole and perpendicular to each other is provided to the analysis device by one sensor. be able to.
According to the inventions of claims 11 to 14, 16 to 18, 29 to 31 , it is possible to secure the comfort of the floor reaction force measuring device to the maximum while maintaining the accuracy of the estimated treading pressure data.
According to the fifteenth aspect of the invention, it is possible to determine the distribution of force components in two directions that are parallel to the upper surface of the sole and orthogonal to each other.
According to the nineteenth aspect of the present invention, it is possible to determine the distribution of force components in two directions that are parallel to the sole upper surface and orthogonal to each other over the entire sole.
According to the twentieth aspect of the present invention, it is possible to perform stepping pressure data sampling for a plurality of subjects having different foot sizes using one floor reaction force measuring device.
According to the invention described in claims 21 and 34 , the load position can be calculated.

According to the invention described in claims 22 to 24 , since the estimation coefficient is identified and the floor reaction force is calculated in the estimation coefficient identification step, the floor reaction force sensor that needs to be mounted on the footwear type floor reaction force measuring device is calculated. The number can be reduced. Therefore, it is possible to secure the flexibility of the sole of the footwear type floor reaction force measuring device attached to the subject and to minimize the adverse effect on the comfort caused by the arrangement of the floor reaction force sensor. In addition, since it is possible to estimate the treading pressure with the force applied to a part of the sole, there is no need to provide a floor reaction force sensor on the entire sole. Applicable to force measuring device. As a result, the same floor reaction force measuring device can be attached to a plurality of subjects having different foot sizes, and suitable data sampling can be performed with a single device for many subjects.
According to the invention of claim 32, since the estimation coefficient is determined for each subject, the estimation accuracy can be improved.
According to the invention of claim 33, since the estimation coefficient is determined for each floor reaction force measuring device, it is possible to improve the estimation accuracy.

Hereinafter, embodiments of a floor reaction force estimation system and a floor reaction force estimation method according to the present invention will be described with reference to the drawings.
FIG. 1 is a schematic diagram of a floor reaction force estimation system (1) according to the present invention.
The floor reaction force estimation system (1) mainly includes a footwear type floor reaction force measurement device (2) and an analysis device (3).
The footwear type floor reaction force measuring device (2) generally has the shape of footwear such as shoes, sandals, slippers, etc. In the example shown in FIG. 1, the footwear type floor reaction force measuring device (slipper shape) ( 2) is shown. Although this invention is not specifically limited, It is preferable to employ | adopt as the floor reaction force measuring apparatus (2) of the kind which does not have the upper part which restrains the circumference | surroundings of foot | legs, such as a sandal and a slipper. . This makes it possible to attach the same floor reaction force measuring device (2) to a plurality of subjects having different foot sizes.
As the analysis device (3), any device having an arithmetic processing function such as a commercially available personal computer can be employed.

The floor reaction force measuring device (2) has a sole part (21) that supports the subject's foot and contacts the ground, and extends upward from the front periphery of the sole part (21) and has a dome shape. An upper part (22) surrounding the upper part of the part, and an insole part (23) which is formed in substantially the same shape and size as the upper surface of the sole part (21) and is fixed to the upper surface of the sole part (21).
Both the sole portion (21) and the insole portion (23) are flexible thin plate-like members, and the insole portion (23) is laminated and integrated on the upper surface of the sole portion (21). The flexibility required to realize natural walking is ensured.

FIG. 2 is a plan view of the sole portion (21).
A plurality of force sensors (24) are fixed to the upper surface of the sole portion (21), and the force sensors (24) are sandwiched between the upper surface of the sole portion (21) and the lower surface of the insole portion (23). A 1st force sensor (24A) is distribute | arranged to the position which supports a test subject's eyelid. A 2nd force sensor (24B) is distribute | arranged to the position which supports a test subject's Chopard joint part. A 3rd force sensor (24C) is distribute | arranged to the position which supports a test subject's 1st MP joint part. A 4th force sensor (24D) is distribute | arranged to the position which supports a test subject's 4th MP joint part. A 5th force sensor (24E) is distribute | arranged to the position which supports a test subject's buttock part. The sixth force sensor (24F) is arranged at a position that supports the vicinity of the third buttocks of the subject.
Outputs from these force sensors (24) are sent to the analysis device (3) using a well-known data transfer technology such as a cable or wireless technology (see FIG. 1).
In the example shown in FIG. 2, force sensors (24) are arranged at six locations. However, the force sensors (24) are arranged at the hip, Chopard joint, fourth MP joint, and the hip. Alternatively, in addition to these four locations, a force sensor (24) may be arranged at the first MP joint or the third collar. Furthermore, as long as the flexibility of the required sole part (21) is not impaired, many may be arranged at the site | part on another sole part (21).

FIG. 3 shows an example of the force sensor (24) shown in FIG. 3 (a) is a schematic perspective view of the force sensor (24), FIG. 3 (b) is a plan view of the force sensor (24), and FIG. 3 (c) is a plan view of FIG. 3 (b). FIG. 3D is a cross-sectional view taken along the line AA, and FIG. 3D is a cross-sectional view taken along the line BB of FIG.
The force sensor (24) shown in FIG. 3 is a three-component load sensor. In the coordinates shown in FIG. 3, the Z axis means a direction orthogonal to the upper surface of the sole portion (21), and the X axis and the Y axis mean directions parallel to the upper surface of the sole portion (21). To do. The X axis and the Y axis are orthogonal to each other.

The force sensor (24) includes a disk part (241), a pair of first legs (242) bent downward from the periphery of the disk part (241) and extending in the X-axis direction, and a disk part (241) A pair of second legs (243) bent downward from the periphery and extending in the Y-axis direction, and a force transmission rod (244) penetrating the center of the force sensor (24) in the Z-axis direction are provided.
The disc part (241), the first leg part (242) and the second leg part (243) are integrally formed using a flexible material such as a rubber material. The disc part (241), the first leg part (242) and the second leg part (243) are made of a thin brass plate, phosphor bronze plate, white plate or aluminum alloy plate having a thickness of about 1 mm.

A plurality of diaphragm strain gauges (Rt1, Rc1, Rt2, Rc2) are bonded to the lower surface of the disc portion (241), and these are used for measuring a load in the Z-axis direction.
Two elements of single-axis strain gauges (Rt3, Rc3, Rt4, Rc4, Rt5, Rc5, Rt6) are formed on the surfaces of the first leg (242) and the second leg (243) that form the force sensor (24). , Rc6) are bonded together. The uniaxial strain gauges (Rc3, Rc4, Rc5, Rc6) are located at the upper part of the legs (242, 243), and the uniaxial strain gauges (Rt3, Rt4, Rt5, Rt6) are the legs (242, 243). Located at the bottom of.
Uniaxial strain gauges (Rt3, Rc3, Rt4, Rc4) are used to measure the load in the X-axis direction. Uniaxial strain gauges (Rt5, Rc5, Rt6, Rc6) are used to measure the weight in the Y-axis direction.

Of the diaphragm strain gauges (Rt1, Rc1, Rt2, Rc2) arranged on the lower surface of the disk portion (241), the strain gauges (Rc1, Rc2) are subjected to compressive strain caused by the stress in the radial direction. The strain gauges (Rt1, Rt2) receive a tensile strain generated due to the stress in the circumferential direction.
Further, when the force sensor (24) receives a force in the positive Z-axis direction (downward) via the force transmission rod (244), the diaphragm strain gauges (Rt1, Rc1) disposed on the lower surface of the disk portion (241). , Rt2, Rc2), the strain gauges (Rt1, Rc1, Rt2, Rc2) are arranged so that the strain gauges (Rt1, Rt2) are subjected to tensile strain and the strain gauges (Rc1, Rc2) are subjected to compressive strain. Determined.

When the force sensor (24) receives a force in the positive direction of the X axis, the strain gauges (Rt3, Rt4) are subjected to tensile strain and the strain gauges (Rc4, Rc3) are subjected to compressive strain. , Rc4, Rc3) are defined.
When the force sensor (24) receives a force in the positive direction of the Y axis, the strain gauges (Rt5, Rt6) are subjected to tensile strain and the strain gauges (Rc5, Rc6) are subjected to compressive strain. , Rc5, Rc6) are determined.

FIG. 4 shows a circuit diagram constituted by the strain gauge, FIG. 4A is a Wheatstone bridge that detects a force in the Z-axis direction, and FIG. 4B shows a force in the X-axis direction. FIG. 4C illustrates a Wheatstone bridge that detects a force in the Y-axis direction.
In FIG. 4, a symbol E indicates a predetermined applied voltage, and a symbol e indicates an output voltage that is output as a result of the resistance change of the strain gauge according to the load.
As shown in FIG. 4, by configuring a Wheatstone bridge circuit for each of the X, Y, and Z axes, it is possible to minimize the influence of a force other than the direction of the detected force.

  In this embodiment, the X-axis direction of the force sensor (24) shown in FIG. 3 is the X-axis direction in the coordinate system shown in FIG. 2, and the Y-axis direction of the force sensor (24) shown in FIG. Each of the force sensors (24A-24F) is a sole portion so that the Y-axis direction is in the coordinate system shown, and the Z-axis direction of the force sensor (24) shown in FIG. 3 is the Z-axis direction in the coordinate system shown in FIG. (21) Fixed on top.

FIG. 5 is a schematic flowchart of the floor reaction force estimation method of the present invention.
The floor reaction force estimation method of the present invention includes an estimation coefficient identification step, a floor reaction force measurement step, and a floor reaction force calculation step.
In the estimation coefficient identification step, first, the floor reaction force measuring device (2) is attached to the subject's foot so that the subject can change the magnitude and load position of the foot on the general floor reaction force meter. Change your posture. Here, the actual measurement value by the floor reaction force meter at a certain specific time point while the subject is walking on the floor reaction force counting is compared with the output value of the force sensor (24A-24F).
Assume that the measured values by the floor reaction force meter are Fx, Fy, Fz, the output value of the force sensor is fxi, fyi, fzi (i = 16), and the estimation coefficients are Axi, Ayi, Azi (i = 16). The estimated values Fx, Fy, Fz of the floor reaction force and the output value of the force sensor have a relationship represented by the following expression.
The following formula models the case where the coordinates of the floor surface and the coordinates of the floor reaction force measuring device match (when the entire bottom surface is in contact with the ground), and the toes or heels float. If so, the calculation is performed in a group of sensors that can be considered to have the same inclination in consideration of bending. In this calculation, coordinate conversion is executed using the inclination angle of each sensor.

Here, Fx means an estimated value of the floor reaction force in the X-axis direction, fxi means an output value generated by the action of the force in the X-axis direction of the force sensor, and Axi means a force in the X-axis direction. Means the estimation coefficient for. Further, when i = 1, it means that it is related to the force sensor (24A), when i = 2, it means that it is related to the force sensor (24B), and when i = 3, it is related to the force sensor (24B). Means related to sensor (24C), i = 4 means related to force sensor (24D), i = 5 means related to force sensor (24E) When i = 6, it means that the force sensor (24F) is related.
Similarly, Fy means an estimated value of the floor reaction force in the Y-axis direction, fyi means an output value generated by the action of the force in the Y-axis direction of the force sensor, and Ayi means a force in the Y-axis direction. Means the estimation coefficient for. Fz means the estimated value of the floor reaction force in the Z-axis direction, fzi means the output value generated by the action of the force in the Z-axis direction of the force sensor, and Azi means the force in the Z-axis direction. Means an estimation coefficient.

In the estimation coefficient identification process, the estimation coefficient (partial regression coefficient) (Axi, Ayi, Azi) is set so that the difference between the estimated value and the value measured by the floor reaction force meter is minimized by techniques such as multiple regression analysis. Identify each one.
Such identification work is performed by transmitting the output from the floor reaction force meter and the output from the floor reaction force measuring device (2) to the analysis device (3) and using the arithmetic processing function of the analysis device (3). Done.

  As a result of the estimation coefficient identification step, the analysis apparatus (3) stores an estimation coefficient matrix C represented by the following expression.

After the estimation coefficient identification step, a floor reaction force measurement step is performed.
In the floor reaction force measurement step, the floor reaction force measurement device (2) is attached to the subject's foot. Then, for example, the subject performs a predetermined operation as an analysis target, such as a walking operation, golf swing, and ascending / descending of stairs.
The force sensor (24A-24F) attached to the floor reaction force measuring device (2) outputs an output corresponding to the force applied to the force sensor (24A-24F) by the predetermined operation by the analyzing device (3). Send to.
As a result, the sensor output value matrix V expressed by the following equation is stored in the analysis device (3).

After the floor reaction force measurement step, a floor reaction force calculation step is performed.
In the floor reaction force calculation step, the analysis device (3) uses the calculation function to integrate the estimation coefficient matrix C and the sensor output value matrix V to calculate an estimated value of the floor reaction force. Therefore, the estimated value (F′x, F′y, F′z) of the floor reaction force is expressed by the following equation.

Furthermore, using the coordinates (x _i , y _i ) from the reference point of the i-th sensor, the load position as the entire floor can be estimated by the following equation.
The following formula models the case where the coordinates of the floor surface and the coordinates of the floor reaction force measuring device match (when the entire bottom surface is in contact with the ground), and the toes or heels float. If so, the calculation is performed in a group of sensors that can be considered to have the same inclination in consideration of bending. In this calculation, coordinate conversion is executed using the inclination angle of each sensor.

  Thus, by identifying the estimation coefficient in advance, it is possible to accurately calculate the floor reaction force using a small number of force sensors. Therefore, it is not necessary to dispose a force sensor over the entire upper surface of the sole portion, and as a result, the flexibility inherent to the sole portion (21) and the insole portion (23) can be maintained. This enables a natural walking motion or other analysis target motion of the subject wearing the floor reaction force measuring device (2), and enables more realistic floor reaction force data sampling.

Note that the estimation coefficient matrix C may be determined for each subject. For example, as described above, the estimation coefficient is identified for the subject (class A), and the estimation coefficient matrix C1 for the subject (class A) is stored in the analysis device (3). And an estimation coefficient is similarly identified with respect to a test subject (B), and the estimation coefficient matrix C2 with respect to a test subject (B) is stored in an analyzer (3).
Thereafter, when the floor reaction force measurement step is executed for the subject (the former), the floor reaction force calculation step uses the estimated coefficient matrix C1 determined for the subject (the former), Calculate the force.
Alternatively, when the floor reaction force measurement process is executed on the subject (second person), the floor reaction force calculation process uses the estimated coefficient matrix C2 determined for the subject (second person) to determine the floor reaction force. Calculate the force.
Thereby, it becomes possible to improve the accuracy of the estimated value of the floor reaction force obtained by the present invention.

In another embodiment, the estimation coefficient matrix C may be determined for each floor reaction force measuring device (2). For example, two floor reaction force measuring devices (2) having different weights are prepared. Then, the lightweight floor reaction force measuring device (2) is attached to the subject's (top) foot, the estimation coefficient identifying step is executed, and the estimation coefficient for the lightweight floor reaction force measuring device (2) is identified, The estimated matrix coefficient C3 for the lightweight floor reaction force measuring device (2) is stored in the analyzing device (3).
Thereafter, the floor reaction force measuring device (2) having a large weight is attached to the subject's (top) foot, the estimation coefficient identifying step is executed, and the estimation coefficient for the floor reaction force measuring device (2) having a large weight is identified, The estimated matrix coefficient C4 for the heavy floor reaction force measuring device (2) is stored in the analyzing device (3).
This makes it possible to accurately analyze the change in floor reaction force due to the weight of the footwear.

FIG. 6 shows an application form of the floor reaction force measurement system (1) shown in FIG. The floor reaction force measurement system (10) shown in FIG. 6 is different from the floor reaction force measurement system (1) shown in FIG. 1 in that an imaging device (4) is provided, but the other configurations are the same. As the imaging device (4), a generally available digital video camera can be employed.
In the floor reaction force measurement step, the floor reaction force measurement device (2) is attached to the subject's foot, and the subject is caused to perform a predetermined operation. When the output from the force sensor (24) installed in the floor reaction force measurement device (2) is transmitted to the analysis device (3), the analysis device (3) sends a trigger signal to the image pickup device (4) to take an image. The device (4) images the subject's foot. The imaging device (4) transmits moving image data obtained by imaging to the analyzing device (3), and the analyzing device (3) stores the moving image data.
Thereby, the time series data of the force sensor (24) and the moving image data obtained by the imaging device (4) are substantially synchronized.

FIG. 7 shows still image data constituting the moving image data obtained from the imaging device (4).
In the floor reaction force calculation step, based on the time series data of the calculated floor reaction force, still image data that reflects the state of the subject's foot at the time of analysis is extracted from the moving image data.
As described above, the laminate of the sole portion (21) and the insole portion (23) of the floor reaction force measuring device (2) used in the present invention has flexibility. Accordingly, a bent state of the sole (sole) observed in a normal walking motion or other motion state is generated.
As shown in FIG. 7, the inclination angle (θ ₁ , θ ₂ ) of the bottom surface of the floor reaction force measuring device (2) with respect to the horizontal plane (H) can be obtained from the still image data.

FIG. 8 is a simplified schematic diagram of coordinate transformation correction.
The force component data output from the floor reaction force measuring device (2) is a force component in a direction orthogonal to the upper surface of the sole portion (21) and in a direction parallel to the upper surface of the sole portion (21). As shown in FIG. 7, when the subject performs a predetermined motion (for example, walking motion), there also occurs a moment when the sole portion (21) is inclined with respect to the horizontal plane (ground). As described above, the coordinate system based on the sole portion (21) changes with time and is dynamic, so that it is difficult to handle the obtained data.
Therefore, transform the obtained data into a coordinate system based on the ground (that is, a coordinate system with two axes parallel to the ground and one axis perpendicular to the ground). Is preferred.

Here, FIG. 7 will be referred to again.
With respect to the ground, the sole portion which is inclined at an angle theta ₁ to the region of (21) as a region A, a sole portion which is inclined at an angle theta ₂ to the region of (21) to a region B. In the region A, it is assumed that the force component fady in the direction from the toe to the heel and the force fadz in the direction orthogonal to the upper surface of the sole portion (21) are calculated.
At this time, when these force components are replaced with the coordinate system (Ys, Zs) based on the ground, the force component Fasy in the direction parallel to the ground and the force component Faz in the direction orthogonal to the ground are It is represented by the following formula.

Similarly, in the region B, it is assumed that the force component fbdy in the direction from the toe to the heel and the force fbdz in the direction orthogonal to the upper surface of the sole portion (21) are calculated.
At this time, when these force components are replaced with the coordinate system (Ys, Zs) based on the ground, the force component Fbsy in the direction parallel to the ground and the force component Fbsz in the direction orthogonal to the ground Is represented by the following equation.

  The (Fasy, Fbsy) and (Fasz, Fbsz) obtained by the above method are summed in a vector manner in consideration of the load position, so that the force component generated on the sole portion (21) is referenced to the ground. It is possible to replace with the coordinate system (Ys, Zs).

  In order to avoid unnecessarily complicating the above description, the description has been made using two-dimensional coordinates. However, application to three-dimensional coordinates can be appropriately performed based on basic mathematical logic. In the above description, in order to clarify the gist of the present invention, the tilt angle is determined using the image pickup device (4) and the image data obtained from the image pickup device (4), but other methods are used. It can also be done.

  For example, a gyro sensor is fixed between the upper surface of the sole portion (21) and the lower surface of the insole portion (23) of the floor reaction force measuring device (2), and the inclination angle of the upper surface of the sole portion (21) is changed by the gyro sensor. Measure the rate (angular velocity). In this case, the gyro sensor is arranged in a region of the upper surface region of the sole portion (21) from a portion contacting the MP joint to a portion contacting the toe and a region contacting the MP joint from the portion contacting the MP joint. It is preferred that This is because it is considered that the sole part (21) of the floor reaction force measuring device (2) is often bent with the MP joint as a boundary according to the human foot skeleton.

The gyro sensor further transmits the measured change rate of the inclination angle of the upper surface of the sole portion (21) to the analysis device (3). The analysis device (3) performs an integral operation on the data sent from the gyro sensor. Thereby, the inclination angle of the upper surface of the sole portion (21) can be calculated.
According to this embodiment, the inclination angle of the upper surface of the sole portion (21) can be stored in the analysis device (3) in time series as numerical data. Therefore, it becomes easy to execute the above-described coordinate conversion correction in time series using the stored data of the inclination angle of the upper surface of the sole portion (21).

FIG. 9 shows an example in which a biaxial acceleration sensor is attached to the upper surface of the sole portion (21), and the inclination angle of the sole portion is measured or calculated.
The acceleration sensor (9) is fixed to the upper surface of the sole portion (21). The acceleration sensor (9) has a direction parallel to the upper surface of the sole portion (21) (in this embodiment, the X-axis direction) and a direction perpendicular to the upper surface of the sole portion (21) (in this embodiment, The acceleration in the Y-axis direction) can be measured.
When the inclination angle of the sole part (21) with respect to the ground is θ, the angle formed by the gravitational acceleration vector g and the acceleration vector a _{y in} the Y-axis direction measured by the acceleration sensor (9) is θ. This relationship can be approximated by the following mathematical expression when the acceleration due to the movement of the sole portion (21) is sufficiently smaller than the gravitational acceleration.

  Based on this relational expression, the measurement value by the acceleration sensor (9) is sent to the analysis device (3), and the analysis device (3) can determine the inclination angle of the sole portion (21). The coordinate transformation calculation described in relation to this can be executed.

As described above, the force sensor (24) can measure a force component in a direction orthogonal to the upper surface of the sole portion (21). It is also possible to use the measured force component in the direction orthogonal to the upper surface of the sole portion (21) for the integral calculation of the analysis device (3).
That is, when all of the force sensors (24A-24F) shown in FIG. 2 (the output of some sensors may be very small depending on the subject) shows a non-zero value, or more than a predetermined threshold value. When the value is shown, it can be considered that the entire bottom surface of the sole portion (21) is in contact with the ground. When the entire bottom surface of the sole portion (21) is in contact with the ground, the top surface of the sole portion (21) is not inclined with respect to the ground. The integrated value obtained is set to a value equal to “0”, and the calculated inclination angle of the upper surface of the sole portion (21) in this state is forcibly set to “0”. As a result, it is possible to remove the integration error caused by the integration calculation, and to improve the accuracy of the subsequent calculation of the tilt angle.
In another embodiment, when all the force sensors (24A-24F) indicate a non-zero value, or when the force sensor (24A-24F) indicates a value equal to or greater than a predetermined threshold, the analysis device (3) 21) By determining that the entire lower surface is in contact with the ground, it is possible to easily compare the contact state of the subject's foot with the obtained treading pressure data, and to analyze various treading pressure data using this Can be performed.

FIG. 10 is a plan view of the sole portion (21), and shows an application example of the embodiment described in relation to FIGS.
In the embodiment shown in FIG. 10, a simple pressure sensor (25A-25F) is used instead of the three-component force sensor (24A-24F) used in the embodiment shown in FIG. The pressure sensors (25A-25F) can measure the load in the vertical direction (in FIG. 10, the Z-axis direction).
In addition, arrangement | positioning of a pressure sensor (25A-25F) is the same as that of the above-mentioned 3 component force load sensor (24A-24F).

11 is a cross-sectional view taken along line AA of the sole portion (21) shown in FIG.
On the sole part (21), sensor layers (26, 27) having substantially the same shape and size as the sole part (21) are laminated. Openings are formed in the sensor layers (26, 27) at positions corresponding to the pressure sensors (25A-25F), and the pressure sensors (25A-25F) protrude from the upper surface of the sensor layer (27) through the openings.

FIG. 12 shows the form of the piezoelectric polymer material disposed in the sensor layers (26, 27).
The piezoelectric polymer material (28) arranged in the sensor layers (26, 27) is made of, for example, P (VDF / TrFE) and has a thin plate corrugated shape. The upper and lower surfaces of the piezoelectric polymer material (28) are coated with conductive ink. Further, the surface of the piezoelectric polymer material (28) is coated with silicon rubber to prevent the piezoelectric polymer material (28) and the conductive ink from peeling off. The upper and lower sides of the piezoelectric polymer material (28) are covered with polyurethane rubber, whereby the sensor layers (26, 27) are formed.
The peak of the piezoelectric polymer material (28) of the sensor layer (26) extends in the width direction of the sole part (21), and the peak of the piezoelectric polymer material (28) of the sensor layer (27) is the sole. It extends in the longitudinal direction of the part (21). As a result, the peak of the sensor layer (26) and the peak of the sensor layer (27) are orthogonal to each other.

10 to 12, when a vertical force is applied to the sole portion (21), the pressure sensor (25A-25F) is deformed, and an output corresponding to the applied vertical force is analyzed. Send to device (3).
When a force in the longitudinal direction of the sole portion (21) is applied to the sole portion (21), the piezoelectric polymer material (28) disposed in the sensor layer (26) is deformed, and the loaded sole portion (21 ) Send the output corresponding to the force in the longitudinal direction to the analysis device (3).
When a force in the width direction of the sole portion (21) is applied to the sole portion (21), the piezoelectric polymer material (28) disposed in the sensor layer (27) is deformed, and the loaded sole portion (21 ) Send an output corresponding to the force in the width direction to the analysis device (3).

Similar to the embodiment shown in FIGS. 1 to 8, the insole part (23) is formed on the sole part (21) on which the pressure sensor (25A-25F) is fixed and the sensor layers (26, 27) are laminated. The floor reaction force measuring device (2) is placed on the subject.
Since the sensor layer (26, 27) transmits an output corresponding to the entire force loaded in the longitudinal direction and the width direction of the sole portion (21) to the analysis device (3), the above estimation calculation is performed by the pressure sensor (25A). Only for the output of -25F).
10 to 12, the sole part (21) and the sensor layers (26, 27) laminated on the sole part (21) are both flexible. Therefore, it is possible to ensure the comfortable wearing comfort of the subject wearing the floor reaction force measuring device (2).
In the embodiment shown in FIGS. 10 to 12, it is also possible to adopt a form in which the pressure sensor (25A-25F) is made of a piezoelectric polymer material and an output corresponding to the amount of compressive deformation is sent to the analysis device (3). .

FIG. 13 shows a further modification of the sole part (21).
On the upper surface of the sole portion (21) shown in FIG. 13, a pressure sensor (25A-25F) formed of a piezoelectric polymer material and a plurality of X-axis direction sensors extending in the longitudinal direction and formed of the piezoelectric polymer material (250) and a plurality of Y-axis direction sensors (251), which extend in the width direction and are formed of a piezoelectric polymer material, are fixed.
The pressure sensors (25A-25F) transmit an output corresponding to the amount of compressive deformation in the Z-axis direction shown in FIG. 13 to the analyzer (3), as described above.

FIG. 14 is a cross-sectional view of the X-axis direction sensor (250) or the Y-axis direction sensor (251).
The X-axis direction sensor (250) and the Y-axis direction sensor (251) each have a substantially square cross section. Since the X-axis direction sensor (250) extends in the longitudinal direction (Y-axis direction) of the sole part (21), the X-axis direction sensor (250) is greatly deformed by receiving a force in the width direction (X-axis direction) of the sole part (21). On the other hand, since the Y-axis direction sensor (251) extends in the width direction (X-axis direction) of the sole portion (21), the Y-axis direction sensor (251) is greatly deformed by receiving a force in the longitudinal direction (Y-axis direction) of the sole portion (21).
Accordingly, the X-axis direction sensor (250) transmits an output corresponding to the force in the width direction of the sole portion (21) to the analysis device (3), and the Y-axis direction sensor (251) is transmitted in the longitudinal direction of the sole portion (21). An output corresponding to the force is transmitted to the analysis device (3).
Similar to the embodiment shown in FIGS. 1 to 8, the insole portion is formed on the sole portion (21) to which the pressure sensor (25A-25F), the X-axis direction sensor (250), and the Y-axis direction sensor (251) are fixed. (23) is placed, and the floor reaction force measuring device (2) is attached to the subject.
The analysis device (3) performs the above-described estimation calculation based on outputs from the pressure sensor (25A-25F), the X-axis direction sensor (250), and the Y-axis direction sensor (251).

15 and 16 are modifications of the embodiment described with reference to FIGS. 13 and 14. FIG. 15 is a cross-sectional view of the sole portion (21), and FIG. 16 shows the internal structure of the deformation layer laminated on the upper surface of the sole portion (21).
As shown in FIG. 15, a deformation layer (29) is laminated on the upper surface of the sole portion (21). The deformable layer (29) is sufficiently flexible to provide a comfortable comfort for a subject wearing the floor reaction force measuring device (2) in a state where the deformable layer (29) is laminated on the sole portion (21). .
A strain gauge (29X) extending in the X-axis direction, a strain gauge (29Y) extending in the Y-axis direction, and a strain gauge (29Z) extending in the Z-axis direction are embedded in the deformation layer (29). The
The strain gauge (29X) extending in the X-axis direction transmits an output corresponding to the deformation amount when the deformation layer (29) is deformed by receiving the force in the width direction of the sole portion (29) to the analysis device (3). To do.
The strain gauge (29Y) extending in the Y-axis direction transmits an output corresponding to the deformation amount when the deformation layer (29) is deformed by receiving the force in the longitudinal direction of the sole portion (29) to the analysis device (3). To do.
The strain gauge (29Z) extending in the Z-axis direction outputs an output corresponding to the deformation amount when the deformation layer (29) is deformed by receiving a force in the thickness direction of the sole portion (29) to the analysis device (3). Send.
The analysis device receives the output from the strain gauges (29X, 29Y, 29Z) and executes the above-described estimation calculation.

  INDUSTRIAL APPLICABILITY The present invention can be suitably used for human walking motion analysis research, balance function evaluation, virtual reality sensors, sports training such as golf, and medical welfare equipment sensors.

1 is a schematic configuration diagram of a floor reaction force estimation system according to the present invention. It is a top view of the sole part of the floor reaction force estimation system which concerns on this invention, and shows arrangement | positioning of a force sensor. It is a figure which shows one Embodiment of the force sensor used for the floor reaction force estimation system of this invention. It is the circuit diagram comprised using the force sensor shown in FIG. It is a schematic flowchart of the floor reaction force estimation method of this invention. It is a schematic block diagram which concerns on other embodiment of the floor reaction force estimation system shown in FIG. It is the still image obtained by imaging the inclination state of the foot at the time of human walking motion. It is a figure explaining the coordinate transformation which the analyzer of the floor reaction force estimation system of this invention performs. It is a figure which shows other embodiment which calculates | requires the inclination-angle of the sole part for performing the coordinate transformation shown in FIG. It is a top view which shows other embodiment of the sole part of the floor reaction force estimation system which concerns on this invention, and shows arrangement | positioning of a force sensor. It is sectional drawing of the sole part shown in FIG. It is a figure which shows the piezoelectric polymer board distribute | arranged in the sensor layer laminated | stacked on the sole part upper surface shown in FIG. It is a top view which shows other embodiment of the sole part of the floor reaction force estimation system which concerns on this invention, and shows arrangement | positioning of a force sensor. It is a figure which shows the cross section of the piezoelectric polymer rod used for the floor reaction force estimation system shown in FIG. 13, and is a figure which represents typically the deformation | transformation form of a piezoelectric polymer rod cross section. It is sectional drawing which shows other embodiment of the sole part of the floor reaction force estimation system which concerns on this invention, and shows arrangement | positioning of a force sensor. It is a figure which shows the internal structure of the deformation | transformation layer laminated | stacked on the sole part shown in FIG. It is sectional drawing of the conventional floor reaction force measuring apparatus. It is an arrangement view of force sensors used in a conventional floor reaction force measuring device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Floor reaction force measuring system 2 ... Floor reaction force measuring device 24 ... Force sensor 3 ... Analysis device

Claims (34)

A floor reaction force estimation system comprising a footwear type floor reaction force measuring device having a flexible sole and an analysis device for analyzing the output of the floor reaction force measuring device,
The floor reaction force measuring device includes force sensors at a plurality of locations of the sole,
The force sensor outputs information related to at least a force component in two directions substantially parallel to the upper surface of the sole and a force component in a direction perpendicular to the upper surface of the sole to the analysis device,
The analysis apparatus calculates a force component in at least two directions substantially parallel to the upper surface of the sole based on the output information, and a first step of calculating a force component in a direction perpendicular to the upper surface of the sole;
Accumulated at least one of the estimated coefficient set in advance in the analysis device, the calculated force component in two directions substantially parallel to the sole upper surface, and the force component in a direction perpendicular to the sole upper surface A second step of
Performing the third step of summing the accumulated values and calculating the floor reaction force ,
The footwear-type floor reaction force measuring apparatus includes an inclination angle detector that detects an inclination angle of the sole with respect to the ground .   From the relationship between the actual measurement value obtained by directly measuring the floor reaction force and the calculated value obtained by the first step obtained when measuring the actual measurement value, the floor reaction force obtained in the third step is obtained. The floor reaction force estimation system according to claim 1, wherein the estimation coefficient is identified so that a difference between the calculated value and the actual measurement value is minimized. The tilt angle detector, according to claim 1, wherein a region existing in the front than the MP joint abutting portion of the sole, to be arranged in a region existing in the rear than the MP joint abutting portion Floor reaction force estimation system. The inclination angle detector measures the change rate of the inclination angle of the sole upper surface and outputs it to the analysis device,
The floor reaction force estimation system according to claim 1 , wherein the analysis device calculates the inclination angle of the sole by integrating the output change rate of the inclination angle. The tilt angle detector measures the angular acceleration of the tilt motion of the sole upper surface and outputs it to the analysis device,
The floor reaction force estimation system according to claim 1 , wherein the analysis device calculates the inclination angle of the sole by integrating the outputted angular acceleration. The inclination angle detector is an acceleration sensor;
The acceleration sensor measures an acceleration component in a direction parallel to the upper surface of the sole and an acceleration component in a direction perpendicular to the upper surface of the sole,
Based on the ratio between the gravitational acceleration acting on the sole and the acceleration component in the parallel direction, the ratio between the gravitational acceleration acting on the sole and the acceleration component in the perpendicular direction, or the ratio between the acceleration component in the parallel direction and the acceleration component in the perpendicular direction The floor reaction force estimation system according to claim 1, wherein an inclination angle of the sole is calculated. The analysis device performs coordinate conversion processing on the output of the force sensor based on the inclination angle of the sole obtained by the output from the inclination angle detector, and the force component in the direction parallel to the ground and the ground The floor reaction force estimation system according to claim 1, wherein a force component in a direction perpendicular to is calculated. When the calculated values of force components in the direction perpendicular to the upper surface of the sole obtained in the first step are not all equal to zero, the analysis device determines that the entire sole surface is in contact with the ground. The floor reaction force estimation system according to claim 7 . When the calculated values of the force components in the direction perpendicular to the upper surface of the sole obtained in the first step are not all equal to zero, the analysis device has been performed before the state becomes not equal to zero. 5. The floor reaction force estimation system according to claim 4 , wherein the value of the integral calculation of the angular velocity is set to zero and the integral calculation is restarted.   The floor reaction force estimation system according to claim 1, wherein the force sensor is a three-component force load sensor. The floor reaction force estimation system according to claim 10 , wherein the force sensor is disposed in a hip, a Chopard joint, a fourth MP joint, and a main hip. 11. The floor reaction force estimation system according to claim 10 , wherein the force sensor is disposed on a hip, a Chopard joint, a fourth MP joint, a mother hip, a first MP joint, and a third hip. The floor reaction force estimation system according to claim 11 , wherein the force sensor is further arranged in any one selected from the group consisting of a first MP joint and a third buttocks. The three-component load sensor is
A disc part,
A plurality of legs extending from the disk and bending downward;
Consisting of a strain gauge attached to the leg,
Of the legs, a pair of legs are attached to the upper surface of the sole and extend in one direction parallel to the upper surface of the sole,
The other pair of legs are attached to the upper surface of the sole and extend in a direction orthogonal to one direction parallel to the upper surface of the sole,
The floor reaction force estimation system according to claim 10, wherein the disc portion and the leg portion are formed of a rubber material. A floor reaction force estimation system comprising a footwear type floor reaction force measuring device having a flexible sole and an analysis device for analyzing the output of the floor reaction force measuring device,
The floor reaction force measuring device includes force sensors at a plurality of locations of the sole,
The force sensor outputs information related to at least a force component in two directions substantially parallel to the upper surface of the sole and a force component in a direction perpendicular to the upper surface of the sole to the analysis device,
The analysis apparatus calculates a force component in at least two directions substantially parallel to the upper surface of the sole based on the output information, and a first step of calculating a force component in a direction perpendicular to the upper surface of the sole;
Accumulated at least one of the estimated coefficient set in advance in the analysis device, the calculated force component in two directions substantially parallel to the sole upper surface, and the force component in a direction perpendicular to the sole upper surface A second step of
Performing the third step of summing the accumulated values and calculating the floor reaction force,
The force sensor comprises a flexible piezoelectric polymer sheet sensor and a pressure sensor,
The piezoelectric polymer sheet sensor measures a force component in two directions parallel to the surface of the sole,
The pressure sensor, the floor reaction force estimation system that is characterized by measuring the perpendicular force component with respect to said sole upper surface. The floor reaction force estimation system according to claim 15 , wherein the pressure sensor is disposed in a hip, a Chopard joint, a fourth MP joint, and a main hip. The floor reaction force estimation system according to claim 15 , wherein the pressure sensor is disposed in a heel part, a Chopard joint part, a fourth MP joint part, a main heel part, a first MP joint part, and a third heel part. The floor reaction force estimation system according to claim 16 , wherein the pressure sensor is further arranged in any one selected from the group consisting of a first MP joint and a third buttocks. The floor reaction force estimation system according to claim 15 , wherein the piezoelectric polymer sheet sensor is substantially the same shape and size as the sole.   The floor reaction force estimation system according to claim 1, wherein the floor reaction force measuring device does not restrain the periphery of the heel.   The floor reaction force estimation system according to claim 1, wherein a load position is further calculated in the third step. From the relationship between the actual value obtained by directly measuring the floor reaction force and the output value of the force sensor obtained when measuring the actual value, the product of the estimation coefficient and the output value of the force sensor and An estimation coefficient identification step for identifying the estimation coefficient so that the difference from the actual measurement value is minimized;
Using a plurality of force sensors disposed on a flexible sole of a footwear type floor reaction force measuring device, at least two force components substantially parallel to the upper surface of the sole and a direction perpendicular to the upper surface of the sole Floor reaction force measurement process for measuring information related to the force component of
Based on the information related to the force component in at least two directions substantially parallel to the upper surface of the sole and the force component in the direction perpendicular to the upper surface of the sole, the force component in two directions substantially parallel to the at least upper surface of the sole A first step of calculating a force component in a direction perpendicular to the upper surface of the sole, a second step of integrating the estimation coefficient and the force component calculated in the first step, and the integrated value. And a floor reaction force calculation step that executes the third step of calculating the floor reaction force ,
The floor reaction force estimation method, wherein the floor reaction force measurement step includes a step of measuring an inclination angle of the sole with respect to the ground . From the relationship between the actual value obtained by directly measuring the floor reaction force and the output value of the force sensor obtained when measuring the actual value, the product of the estimation coefficient and the output value of the force sensor and An estimation coefficient identification step for identifying the estimation coefficient so that the difference from the actual measurement value is minimized;
Using a plurality of force sensors disposed on a flexible sole of a footwear type floor reaction force measuring device, at least two force components substantially parallel to the upper surface of the sole and a direction perpendicular to the upper surface of the sole Floor reaction force measurement process for measuring information related to the force component of
Based on the information related to the force component in at least two directions substantially parallel to the upper surface of the sole and the force component in the direction perpendicular to the upper surface of the sole, the force component in two directions substantially parallel to the at least upper surface of the sole A first step of calculating a force component in a direction perpendicular to the upper surface of the sole, a second step of integrating the estimation coefficient and the force component calculated in the first step, and the integrated value. And a floor reaction force calculation step that executes the third step of calculating the floor reaction force ,
The floor reaction force measuring step includes a step of measuring a rate of change of an inclination angle of the sole upper surface;
The floor reaction force calculating step includes a step of calculating the inclination angle of the sole by integrating the measured angular velocity . From the relationship between the actual value obtained by directly measuring the floor reaction force and the output value of the force sensor obtained when measuring the actual value, the product of the estimation coefficient and the output value of the force sensor and An estimation coefficient identification step for identifying the estimation coefficient so that the difference from the actual measurement value is minimized;
Using a plurality of force sensors disposed on a flexible sole of a footwear type floor reaction force measuring device, at least two force components substantially parallel to the upper surface of the sole and a direction perpendicular to the upper surface of the sole Floor reaction force measurement process for measuring information related to the force component of
Based on the information related to the force component in at least two directions substantially parallel to the upper surface of the sole and the force component in the direction perpendicular to the upper surface of the sole, the force component in two directions substantially parallel to the at least upper surface of the sole A first step of calculating a force component in a direction perpendicular to the upper surface of the sole, a second step of integrating the estimation coefficient and the force component calculated in the first step, and the integrated value. And a floor reaction force calculation step that executes the third step of calculating the floor reaction force ,
The floor reaction force measuring step includes a step of measuring an angular acceleration of a tilting motion of the upper surface of the sole;
The floor reaction force calculating method includes the step of integrating the measured angular acceleration to calculate the inclination angle of the sole . Measuring the inclination angle of the sole with respect to the ground includes measuring an acceleration component in a direction parallel to the upper surface of the sole and an acceleration component in a direction perpendicular to the upper surface of the sole, among gravitational acceleration components;
Calculating the tilt angle based on a ratio between a gravitational acceleration and the acceleration component in the parallel direction, a ratio between the gravitational acceleration and the acceleration component in the right direction, or a ratio between the acceleration component in the parallel direction and the acceleration component in the right direction. The floor reaction force estimation method according to claim 22, further comprising : The floor reaction force calculation step determines that the entire sole surface is grounded with respect to the ground when the output values for the forces perpendicular to the sole upper surface from the plurality of force sensors are not all equal to zero. The floor reaction force estimation method according to any one of claims 22 to 24 , further comprising a step. The floor reaction force calculation step is performed before all of the output values for the force in the direction perpendicular to the sole upper surface from the force sensors are not equal to zero when the output values are not equal to zero. 25. The floor reaction force estimation method according to claim 23 , further comprising the step of setting the integrated value to a value equal to zero. The floor reaction force calculating step performs coordinate conversion based on the measured inclination angle of the sole, and calculates a force in a direction perpendicular to the ground and a force in a direction parallel to the ground. The floor reaction force estimation method according to claim 22 , further comprising: Information relating to the perpendicular force component with respect to said sole upper surface, a heel portion, Chopard joint, the 4MP joint, according to any of claims 22 to 24, characterized in that measured in the mother toes Method for estimating floor reaction force. Information relating to a force component in a direction perpendicular to the upper surface of the sole is measured in a hip, a Chopard joint, a fourth MP joint, a hip, a first MP joint, and a third hip. The floor reaction force estimation method according to any one of claims 22 to 24 . Information relating to the perpendicular force component with respect to said sole upper surface, according to claim 29, wherein the further measured in either selected from the group consisting of a 1MP joint portion and the third foot portion Method for estimating floor reaction force. The floor reaction force estimation method according to any one of claims 22 to 24, wherein the estimation coefficient identification step is executed for each subject, and the estimation coefficient is determined for each subject. A step of preparing a plurality of the footwear type floor reaction force measuring devices;
The estimating coefficient identification step is performed in a plurality of footwear type floor reaction force measuring device by which the said prepared claims 22 to 24, characterized in that the estimated coefficient is determined for each fulfillment product type floor reaction force measuring device The floor reaction force estimation method according to any one of the above. The floor reaction force estimation method according to any one of claims 22 to 24 , wherein a load position is further calculated in the third step.

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