JP2013113780A - Pressure sensor, information processor, and electrode determination method - Google Patents

Abstract

[PROBLEMS] To provide a pressure sensor, an information processing device, and an electrode determination method capable of clearly detecting the state of landing and getting off the sole without depending on individual differences in the foot size of the wearer of the walking assist device. I will provide a.
The present invention includes an electrode sheet provided with a first electrode and a plurality of second electrodes, and a pressure-sensitive sheet whose surface resistance changes depending on pressure, and one surface of the pressure-sensitive sheet. And one surface of the electrode sheet is overlapped with each other, and is a pressure sensor mounted between the sole of a person and the ground. In the pressure sensor, the first electrode and the plurality of second electrodes are provided at different positions on the surface of the electrode sheet, respectively, and are the surface of the pressure-sensitive sheet. Conductive wires for electrically connecting a voltage corresponding to the resistance of the region including the surface located between the first electrode and the second electrode to an information processing device that measures each second electrode It is drawn from each said electrode.
[Selection] Figure 1

Description

  The present invention relates to the technical field of a sheet-like pressure sensor used, for example, as an insole for shoes.

  In recent years, rehabilitation has been performed in a state where a walking assist device using a driving source is mounted on, for example, a knee disease patient (see, for example, Patent Document 1). The walking assist device assists the wearer by continuously giving a predetermined walking pattern to the wearer as a patient. Thus, the wearer can walk independently so as to follow the movement. However, the wearer may not be able to follow during this rehabilitation or may become unstable walking against his / her intentions due to wandering. Therefore, a walking assist device that gives the wearer a walking pattern according to the walking state of the wearer is desired. In order to know the walking state of the wearer, for example, how to apply the load on the user's foot, balance, wobble, etc., for example, a pressure distribution sensor having a pressure detection region in which a number of pressure sensitive sensors are arranged in a grid Can be used (see, for example, Patent Document 2).

JP 2002-301124 A JP 2010-69227 A

  By the way, in assisting the wearer's walking with the walking assist device, it is important to control the knee joint motor and the like. In order to allow the wearer to perform this control without difficulty, a pressure sensor that can clearly sense the landing state and the leaving state of the sole of the wearer is required. Such a pressure sensor is desirably provided, for example, on the insole of a rehabilitation shoe of a wearer of the walking assistance device. However, there is an individual difference in the size of the foot of the wearer, and there is a problem that the sensitivity of whether or not the state of landing and getting off can be clearly detected varies depending on the individual difference in foot size.

  Therefore, the present invention has been made in view of the above points, and it is possible to clearly sense the state of landing and leaving the foot without depending on individual differences in the size of the foot of the wearer of the walking assistance device. It is an object of the present invention to provide a pressure sensor, an information processing apparatus, and an electrode determination method capable of performing the above.

  In order to solve the above-mentioned problem, the invention according to claim 1 includes an electrode sheet provided with a first electrode and a plurality of second electrodes, and a pressure-sensitive sheet whose surface resistance changes due to pressure, The pressure sensor is configured to overlap one surface of the pressure sensitive sheet and one surface of the electrode sheet, and is a pressure sensor mounted between a person's sole and the ground. The second electrodes are provided at different positions on the surface of the electrode sheet, respectively, and are the surfaces of the pressure-sensitive sheet between the first electrode and the second electrode. Conductive wires for electrically connecting a voltage corresponding to the resistance of a region including the surface to be positioned to an information processing device that measures each second electrode are drawn from each of the electrodes. .

  According to a second aspect of the present invention, in the pressure sensor according to the first aspect, the pressure sensor is provided on an insole of a shoe.

  A third aspect of the present invention is the pressure sensor according to the first or second aspect, wherein each of the electrodes has an elliptical or rectangular shape extending in one direction and the extending direction. It is characterized by being arranged in parallel at a predetermined interval in a direction orthogonal to

  Invention of Claim 4 is an information processing apparatus electrically connected to the said conducting wire pulled out from the pressure sensor of Claim 1, Comprising: On the said surface of the said pressure sensitive sheet with which the said pressure sensor is provided And measuring means for measuring, for each of the second electrodes, a voltage corresponding to a resistance of a region including the surface located between the first electrode and the second electrode.

  According to a fifth aspect of the present invention, in the information processing apparatus according to the fourth aspect, the measuring means is configured such that the sole of the wearer who wears the pressure sensor between the sole and the ground performs landing and leaving. In a repeated state, the voltage is measured for each of the second electrodes, and the information processing device is configured to measure the plurality of second voltages based on the voltages measured for the second electrodes by the measuring unit. It is further characterized by further comprising a determining means for determining the second electrode that is most suitable for distinguishing between the landing and the leaving of the two electrodes.

  The invention according to claim 6 includes an electrode sheet provided with a first electrode and a plurality of second electrodes, and a pressure-sensitive sheet whose surface resistance is changed by pressure, and one of the pressure-sensitive sheets is provided. A pressure sensor that is configured to overlap a surface and one surface of the electrode sheet, and is mounted between a human foot sole and the ground, wherein the first electrode and the plurality of second electrodes are: Each of the surfaces of the pressure-sensitive sheet that is provided at different positions on the surface of the electrode sheet and includes the surface that is positioned between the first electrode and the second electrode. A pressure sensor that is electrically connected to an information processing apparatus that measures a voltage corresponding to the resistance of each second electrode for each of the second electrodes, and the pressure sensor that is extracted from the pressure sensor. An information processing apparatus electrically connected to the conductor; An electrode determination method for measuring the voltage for each of the second electrodes by using a foot of a wearer who wears the pressure sensor between the sole and the ground repeatedly landing and leaving the floor In a state, a voltage corresponding to the resistance of a region including the surface located between the first electrode and the second electrode on the surface of the pressure-sensitive sheet is measured for each second electrode. And the second electrode optimal for distinguishing between the landing and the leaving bed among the plurality of second electrodes based on each voltage measured for each second electrode And a determining step for determining.

  According to the present invention, in the pressure sensor, the information processing apparatus that measures the voltage corresponding to the resistance of the region including the surface located between the first electrode and the second electrode for each second electrode is electrically connected. Since the lead wires for connecting to each other are drawn out from the respective electrodes, it is possible to clearly detect the state of landing and leaving the foot without depending on individual differences in the foot size of the wearer of the walking assistance device It becomes possible.

It is a figure which shows the structure of a sole sensor. It is a conceptual diagram at the time of measuring the surface resistance of the pressure sensitive sheet of a sole sensor. It is a figure which shows the voltage according to the surface resistance of the area | region containing the surface located between the electrode A and electrodes B1-B4 for every electrode B1-B4. It is a figure which shows the circuit structural example from the conducting wire L1-L5 pulled out from the electrode A and the electrodes B1-B4 to the control part C. FIG. (A) is a figure which shows the voltage example (For example, voltage V1 between the electrode A and the electrode B1) from the sole sensor 1 for right feet, and the sole sensor 1 for left feet. (B) is a figure which shows the relationship between size S1-S4 of a wearer's leg | foot, and electrode B1-B4.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. In addition, embodiment described below is embodiment when the "pressure sensor with which it wears between a person's sole and the ground" concerning this invention is applied to a sole sensor. The sole sensor according to the present embodiment is provided on the insole of the rehabilitation shoe (in other words, the sole sensor itself is used as the insole of the rehabilitation shoe). Then, a wearer of a walking assistance device (not shown) wears rehabilitation shoes to perform rehabilitation.

  First, with reference to FIG.1 and FIG.2, the structure of the sole sensor which concerns on this embodiment is demonstrated. FIG. 1 is a diagram showing a configuration of a sole sensor. FIG. 2 is a conceptual diagram when the surface resistance of the pressure-sensitive sheet of the sole sensor is measured.

  As shown in FIG. 1, the sole sensor 1 according to the present embodiment includes a pressure-sensitive sheet 11 whose surface (surface) resistance is changed by pressure, an electrode A (an example of a first electrode), and a plurality of electrodes B1 to B4. The electrode sheet 12 is provided with (an example of a second electrode), and one surface of the pressure-sensitive sheet 11 and one surface of the electrode sheet 12 are configured to overlap each other.

  Specifically, after the electrode sheet 12 is inserted into the rehabilitation shoe, the foot sensor 1 is mounted by inserting the pressure sensitive sheet 11 on the electrode sheet 12. Note that the pressure-sensitive sheet 11 and the electrode sheet 12 are preferably formed in a foot shape as shown in FIG. Although it is good also as a shape only around a buttocks, making it a foot shape can prevent a wearer from feeling uncomfortable, and can also prevent malfunction due to the displacement of the insole.

  As shown in FIG. 2, it is desirable to apply a cushioning material whose surface resistance is changed by being pressed from above as shown in FIG. 2 (the surface resistance is reduced when the pressure is applied). . Thereby, it becomes possible to walk without giving an uncomfortable feeling to the wearer wearing the rehabilitation shoes, and the durability of the electrode sheet 12 can be increased.

  On the other hand, the electrode sheet 12 is made of, for example, FPC (Flexible Printed Circuits), and is configured by laminating copper as an electrode on polyimide as an insulator (in the electrode sheet 12 alone, the electrodes are insulated by polyimide). ing. Polyimide keeps its shape as an insole for rehabilitation shoes, eliminates misalignment, and increases durability. The exposed electrode is treated with gold plating or the like to prevent deterioration due to rust under moisture or high humidity.

  The electrode A and the plurality of electrodes B1 to B4 are respectively provided at different positions on the surface of the electrode sheet 12, and are the surfaces of the pressure sensitive sheet 11 between the electrode A and the electrodes B1 to B4. Is electrically connected to an information processing device (for example, a control unit of a walking assist device) that measures a voltage (potential difference between two electrodes) corresponding to the surface resistance of a region including the surface positioned at each of the electrodes B1 to B4. Conductor wires (copper wires) L1 to L5 are drawn from the electrodes A and B1 to B4. The electrode A and the plurality of electrodes B1 to B4 are provided on the heel of the sole of the wearer and the periphery thereof in the electrode sheet 12 so that the pressure of the buttock of the wearer wearing the rehabilitation shoes can be detected. ing. Although it is most effective to provide electrodes on the buttocks of the sole of the wearer and in the vicinity thereof, electrodes may be provided on portions other than the heel.

  Further, in the example of FIG. 1, each of the electrodes A, B1 to B4 has a rectangular shape (in other words, a strip) extending long in one direction (the width direction of the foot, in other words, the direction orthogonal to the straight direction of the wearer). And are arranged in parallel at a predetermined interval in a direction orthogonal to the long extending direction (width direction). In the example of FIG. 1, the electrode A is disposed on the toe side, and the electrodes B <b> 1 to B <b> 4 are disposed on the rear side of the heel so as to form a plurality of parallel lines. . The electrodes A and B1 to B4 may have an elliptical shape that extends long in the width direction of the foot. In the example of FIG. 1, four second electrodes B1 to B4 are provided, but the number of second electrodes is not limited to this, and may be three or less, or five or more. There may be.

  FIG. 3 is a diagram illustrating a voltage corresponding to the surface resistance of a region including a surface located between the electrode A and the electrodes B1 to B4 for each of the electrodes B1 to B4. The example of FIG. 3A shows the voltage V1 corresponding to the surface resistance (R1) of the region including the surface located between the electrode A and the electrode B1. The example of FIG. 3B shows the voltage V2 corresponding to the surface resistance (R1 + R2) of the region including the surface located between the electrode A and the electrode B2. In addition, the example of FIG. 3C shows a voltage V3 corresponding to the surface resistance (R1 + R2 + R3) of a region including a surface located between the electrode A and the electrode B3. In addition, the example of FIG. 3D shows a voltage V4 corresponding to the surface resistance (R1 + R2 + R3 + R4) of a region including a surface located between the electrode A and the electrode B4.

  Such voltages V1 to V4 (in other words, surface resistance) are measured by, for example, the control unit of the walking assist device.

  FIG. 4 is a diagram illustrating a circuit configuration example from the conductive wires L1 to L5 drawn from the electrode A and the electrodes B1 to B4 to the control unit C. The control unit C includes, for example, a CPU, a RAM, a ROM, and the like, and functions as a measurement unit and a determination unit in the present invention when the CPU executes a program stored in the ROM, for example.

  In the example of FIG. 4, the conducting wire L1 drawn out from the electrode A is electrically connected to one end of the amplifier Ap via the terminal T1. On the other hand, the conducting wires L2 to L5 drawn from the electrodes B1 to B4 are connected to the switch SW via the terminals T2 to T5, and the conducting wires drawn from any of the electrodes B1 to B4 selected by the switch SW ( Any one of L2 to L5) is electrically connected to the other end of the amplifier Ap via a terminal (any one of T2 to T5).

  The output terminal of the amplifier Ap is connected to the input terminal of the control unit C. Thereby, the voltage V1 (amplitude) between the electrode A and the electrode B1 selected by the switch SW is amplified by the amplifier Ap, and the amplified voltage V1 (in other words, the surface resistance) is measured by the control unit C. (According to switching of the switch SW, the electrodes B1 to B4 are measured in order). Note that the switching of the switch SW is controlled by, for example, the control unit C (for example, controlled to switch at a predetermined interval). Thus, if it comprises so that electrode B1-B4 may be switched by switch SW, the number of amplifier Ap can be reduced and the space and cost which provide amplifier Ap can be reduced. However, an amplifier Ap may be provided for each of the electrodes B1 to B4. In this case, it is not necessary to provide the switch SW, and the output terminal of each amplifier Ap is connected to a separate input terminal of the control unit C. Thereby, the voltage V1-V4 between the electrode A and each electrode B1-B4 can be simultaneously measured by the control part C. FIG.

  By the way, the voltages V1 to V4 for the electrodes B1 to B4 are in a state in which the soles of the wearers wearing rehabilitation shoes on both feet (that is, the wearers wearing the sole sensor 1) are repeatedly landing and getting off. It is desirable to measure in a state of stepping. That is, it is desirable to measure the voltages V1 to V4 from the right foot sole sensor 1 and the left foot sole sensor 1 in order to see the timing of landing and leaving the right foot and left foot.

  Then, the control unit C distinguishes between the landing on the sole of the wearer and the getting out of the plurality of electrodes B1 to B4 based on the voltages V1 to V4 measured for the electrodes B1 to B4 as described above. The most suitable electrode (any one of B1 to B4) is determined. Here, the optimum electrode for distinguishing between the landing of the foot of the wearer and the leaving of the floor is, for example, the rate of change in voltage (from per unit time) at the time of leaving from the landing among the plurality of electrodes B1 to B4. This means the electrode with the largest change rate (slope). Ideally, it is desirable that the voltage has a steep change (steep rising) (the waveform selection of this pattern can realize a foot sensor independent of the patient's condition, foot size, and individual difference). This is because a gentle voltage change makes it difficult to clearly detect the state of landing and getting off the sole.

  The determination of the optimum electrode is performed, for example, by the control unit C calculating a voltage change rate from the measured voltage for each of the electrodes B1 to B4 and comparing them. Alternatively, the optimum electrode may be determined by displaying the measured voltage waveform on a monitor and designating the optimum voltage waveform from the operation unit by an operator or administrator. In the subsequent rehabilitation, the signal (voltage) input from the determined electrode is set to be used (for example, the determined electrode is selected by the switch SW), and the walking assist device assists the wearer in walking. Will be.

  FIG. 5A is a diagram illustrating a waveform example of a voltage (for example, voltage V1 between the electrode A and the electrode B1) from the sole sensor 1 for the right foot and the sole sensor 1 for the left foot. When the sole sensor 1 is used as a switch for landing and leaving the floor, it is necessary that the floor sensor 1 approaches the low level and reaches the high level when leaving the floor. FIG. 5B is a diagram showing the relationship between the wearer's foot sizes S1 to S4 and the electrodes B1 to B4. In the example shown in FIG. 5A, the waveform α shown by a solid line shows an ideal voltage waveform, and in this waveform α, there is a steep rise at the time of leaving from landing, so And can clearly detect the condition of getting out of bed. In the example of FIG. 5B, this waveform α corresponds to, for example, the voltage between the voltage A and the electrode B3 when the size of the wearer's foot is “S3”. It is determined as the optimum electrode. Note that when the size of the wearer's foot is “S3”, the voltage between the voltage A and the electrode B1 has a smaller change rate than the voltage between the voltage A and the electrode B3 (that is, a moderate voltage). Change), it is not an optimal electrode.

  On the other hand, in FIG. 5A, with the waveform β indicated by a broken line, there is no change in voltage during landing to get off, so it is difficult to distinguish between landing and getting off. 5B corresponds to the voltage between the voltage A and the electrode B4 when the size of the wearer's foot is “S3”, for example. That is, in this case, since pressure from the wearer's heel is not applied between the electrode B3 and the electrode B4, the surface resistance at the time of landing between the electrode B3 and the electrode B4 is the landing between the other electrodes. This is because it becomes extremely large (for example, close to infinity) compared to the surface resistance at the time.

  As described above, according to the above embodiment, in the pressure sensor 1 whose surface resistance value changes according to the pressure, the electrode A in the width direction is provided on the toe side around the heel, and the predetermined value is provided on the rear side of the heel. By arranging the electrodes B1 to B4 in the width direction so as to be a plurality of parallel lines, and measuring the change in voltage (surface resistance) in the stepped state with the electrodes A and B1 to B4, An appropriate B electrode can be determined as a trigger suitable for the person. Thereby, it is possible to realize a sole sensor that can clearly detect the state of landing and getting off the foot without depending on individual differences in foot size.

  Moreover, according to the said embodiment, it becomes what match | combined with a wearer with the sole sensor 1 for a walk assistance apparatus, the malfunctioning as a trigger is lost, and walk assist can be stabilized. Furthermore, the preparation of the electrode sheet 12 for the sole sensor 1 can be minimized, and the set time can be shortened. Moreover, it is not necessary to prepare many sole sensors in advance, and it can be avoided that the selection takes time.

  In the above embodiment, the case where the pressure sensor of the present invention is applied to the sole sensor has been described as an example. However, the pressure sensor may be applied to other sensors.

DESCRIPTION OF SYMBOLS 1 Foot sensor 11 Pressure sensitive sheet 12 Electrode sheet A B1-B4 Electrode Ap Amplifier C Control part

Claims (6)

An electrode sheet provided with a first electrode and a plurality of second electrodes; and a pressure-sensitive sheet whose surface resistance is changed by pressure; one side of the pressure-sensitive sheet; and one of the electrode sheets It is a pressure sensor that is composed of overlapping surfaces and is worn between the soles of people and the ground,
The first electrode and the plurality of second electrodes are provided at different positions on the surface of the electrode sheet, respectively, and are the surface of the pressure-sensitive sheet, the first electrode and the first electrode Conductive wires for electrically connecting a voltage corresponding to the resistance of the region including the surface located between the two electrodes to an information processing device for measuring each second electrode are drawn out from the respective electrodes. A pressure sensor.   The pressure sensor according to claim 1, wherein the pressure sensor is provided on a shoe insole.   Each of the electrodes has an elliptical or rectangular shape extending long in one direction, and is arranged in parallel at a predetermined interval in a direction orthogonal to the extending direction. The pressure sensor according to 1 or 2. An information processing apparatus electrically connected to the conducting wire drawn out from the pressure sensor according to claim 1,
A voltage corresponding to the resistance of a region including the surface that is located between the first electrode and the second electrode on the surface of the pressure-sensitive sheet included in the pressure sensor for each of the second electrodes. An information processing apparatus comprising a measuring means for measuring. The measuring means measures the voltage for each of the second electrodes in a state in which the sole of the wearer wearing the pressure sensor between the sole and the ground repeats landing and getting off,
The information processing apparatus is optimal for distinguishing between the landing and the leaving bed among the plurality of second electrodes based on the voltages measured for the second electrodes by the measuring means. The information processing apparatus according to claim 4, further comprising a determination unit that determines the second electrode. An electrode sheet provided with a first electrode and a plurality of second electrodes; and a pressure-sensitive sheet whose surface resistance is changed by pressure; one side of the pressure-sensitive sheet; and one of the electrode sheets A pressure sensor configured to overlap with a surface and worn between a sole of a person and the ground, wherein the first electrode and the plurality of second electrodes are respectively on the surface of the electrode sheet. The voltage corresponding to the resistance of a region including the surface that is provided at different positions and includes the surface that is located between the first electrode and the second electrode on the surface of the pressure-sensitive sheet. Pressure sensors that are electrically connected to the information processing apparatus that measures each of the two electrodes, and the information that is electrically connected to the conductors that are drawn from the pressure sensors. And the second electrode using a processing apparatus An electrode decision process of measuring the voltage on the bets,
The first electrode and the second electrode on the surface of the pressure-sensitive sheet in a state in which the sole of the wearer wearing the pressure sensor between the sole and the ground repeats landing and getting off. Measuring a voltage corresponding to a resistance of a region including the surface located between the second electrode and the second electrode;
Determination of determining the second electrode that is most suitable for distinguishing the landing and the leaving from the plurality of second electrodes based on each voltage measured for each second electrode Steps,
An electrode determination method comprising:

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