JP7459965B2 - Discrimination device, discrimination system, discrimination method, and program - Google Patents

Description

The present disclosure relates to a discrimination device and the like that discriminate walking.

Due to the growing interest in health care that manages physical condition, services that measure gait, including gait characteristics, and provide users with information according to the gait are attracting attention. For example, there are attempts to implement an inertial measurement device in footwear such as shoes and utilize data regarding a user's gait (hereinafter also referred to as gait data) as big data. In order to utilize gait data as big data, it is necessary to clearly distinguish from which leg each of the large amounts of gait data collected comes from.

Patent Document 1 discloses a locomotion analysis device that identifies sections or times corresponding to each step of the left and right feet on data obtained from an acceleration sensor attached to a person's waist. The device in Patent Document 1 generates a position waveform by performing a second-order integration of the waveform of the person's acceleration in the left and right direction. The device in Patent Document 1 identifies sections or times corresponding to each step of the left and right feet based on a processed position waveform from which components obtained by performing a moving average process on the position waveform have been removed.

JP 2016-220923 A

The device in Patent Document 1 identifies sections or times corresponding to each step of the left and right feet on data obtained from an acceleration sensor attached to a person's waist. In order to verify the characteristics of the gait of each of the left and right feet, it is preferable to use data measured by sensors attached to the left and right feet. However, the method in Patent Document 1 was unable to determine which foot the data came from, based on the data measured by sensors attached to the left and right feet.

An object of the present disclosure is to provide a discrimination device and the like that can discriminate from which foot a walking waveform originates, based on data measured by sensors attached to the left and right feet.

A discrimination device according to one embodiment of the present disclosure includes a waveform generation unit that generates a gait waveform using sensor data relating to foot movement, a detection unit that detects the timing of heel-strike and toe-off from the gait waveform of the rotation angle in the sagittal plane, and a discrimination unit that determines whether the gait waveform originates from data on the left or right foot based on characteristics of the gait waveform of the rotation angle in the coronal plane at the timing of heel-strike and toe-off.

In one embodiment of the discrimination method disclosed herein, a computer generates a gait waveform using sensor data related to foot movement, detects the timing of heel-strike and toe-off from the gait waveform of the rotation angle in the sagittal plane, and determines whether the gait waveform being verified originates from data for the left or right foot based on the characteristics of the gait waveform of the rotation angle in the coronal plane at the timing of heel-strike and toe-off.

A program according to one aspect of the present disclosure includes a process of generating a walking waveform using sensor data related to foot movement, and a process of detecting the timing of heel contact and toe separation from the walking waveform of rotation angle in the sagittal plane. and a process of determining whether the gait waveform under verification is derived from the data of the left or right foot, based on the gait waveform characteristics of the rotation angle in the coronal plane at the timing of heel contact and toe liftoff. have it executed.

According to the present disclosure, it is possible to provide a discrimination device etc. that can determine whether a walking waveform originates from the left or right foot based on data measured by sensors attached to the left and right feet.

1 is a block diagram showing an example of a configuration of a determination system according to a first embodiment. It is a conceptual diagram showing an example of arrangement of data acquisition devices of a discrimination system concerning a 1st embodiment. FIG. 2 is a conceptual diagram for explaining a coordinate system set in the data acquisition device of the discrimination system according to the first embodiment. FIG. 2 is a conceptual diagram for explaining a human body surface applied to the discrimination device of the discrimination system according to the first embodiment. 3 is a conceptual diagram for explaining a walking event detected by the discrimination device of the discrimination system according to the first embodiment. FIG. FIG. 2 is a conceptual diagram showing an example of a trajectory of a center of foot pressure (COP) in a normal walking state. 2 is a block diagram showing an example of a configuration of a data acquisition device of the discrimination system according to the first embodiment. FIG. FIG. 2 is a block diagram showing an example of the configuration of a discriminating device of the discriminating system according to the first embodiment. It is a graph showing an example of a walking waveform generated by the discrimination device of the discrimination system according to the first embodiment. 5 is a flowchart for explaining an example of an operation of the discrimination device of the discrimination system according to the first embodiment. FIG. 11 is a block diagram showing an example of a configuration of a determination system according to a second embodiment. It is a block diagram showing an example of the composition of the discrimination device of the discrimination system concerning a 2nd embodiment. 13 is a conceptual diagram for explaining a display example of an analysis result of a discrimination device of a discrimination system according to a second embodiment. FIG. 10 is a flowchart for explaining an example of an operation of a discrimination device of a discrimination system according to a second embodiment. It is a block diagram showing an example of composition of a discrimination device concerning a 3rd embodiment. FIG. 2 is a block diagram showing an example of a hardware configuration for implementing the discrimination device according to each embodiment.

EMBODIMENT OF THE INVENTION Below, the form for implementing this invention is demonstrated using drawing. However, although the embodiments described below include technically preferable limitations for carrying out the present invention, the scope of the invention is not limited to the following. In addition, in all the figures used for the description of the following embodiments, the same reference numerals are given to the same parts unless there is a particular reason. Furthermore, in the following embodiments, repeated explanations of similar configurations and operations may be omitted.

(First embodiment)
First, a discrimination system according to a first embodiment of the present disclosure will be described with reference to the drawings. The discrimination system of this embodiment measures data (also referred to as gait data) resulting from features (also referred to as gait) included in a user's walking pattern. For example, gait data is time-series data regarding physical quantities related to foot movements. For example, the physical quantity related to foot movement includes sensor data such as acceleration (also referred to as spatial acceleration) measured by an acceleration sensor and angular velocity (also referred to as spatial angular velocity) measured by an angular velocity sensor. The discrimination system of this embodiment analyzes the measured gait data to discriminate from which leg, the left or the right, the gait data originates from.

(composition)
FIG. 1 is a block diagram showing the configuration of a discrimination system 1 of this embodiment. The discrimination system 1 includes a data acquisition device 11 and a discrimination device 12. The data acquisition device 11 and the discrimination device 12 may be connected by wire or wirelessly. The data acquisition device 11 and the discrimination device 12 may be configured as a single device. Further, the data acquisition device 11 may be removed from the configuration of the discrimination system 1, and the discrimination system 1 may be configured with only the discrimination device 12. Although only one data acquisition device 11 is shown in FIG. 1, in this embodiment, one identical data acquisition device 11 (two in total) is arranged in association with both the left and right feet.

The data acquisition device 11 is installed on the left and right feet. For example, the data acquisition device 11 is installed in footwear such as shoes. In this embodiment, an example in which the data acquisition device 11 is placed at the back of the arch of the left and right feet will be described. The data acquisition device 11 includes an acceleration sensor and an angular velocity sensor. The data acquisition device 11 measures physical quantities related to the movement of the foot of a user wearing the footwear, such as spatial acceleration and spatial angular velocity. The physical quantities related to the movement of the foot measured by the data acquisition device 11 include not only acceleration and angular velocity, but also velocity and angle calculated by integrating the acceleration and angular velocity. In addition, the physical quantities related to the movement of the foot measured by the data acquisition device 11 also include a position calculated by integrating the acceleration twice. The data acquisition device 11 converts the measured physical quantities into digital data (also called sensor data). The data acquisition device 11 transmits the converted sensor data to the discrimination device 12. For example, the data acquisition device 11 is connected to the discrimination device 12 via a mobile terminal (not shown) carried by the user.

A mobile terminal (not shown) is a communication device that can be carried by a user. For example, a mobile terminal is a mobile communication device having a communication function such as a smartphone, a smart watch, or a mobile phone. The mobile terminal receives sensor data regarding the movement of the user's feet from the data acquisition device 11. The mobile terminal transmits the received sensor data to a server or the like in which the discrimination device 12 is installed. Note that the functions of the discrimination device 12 may be realized by an application installed on a mobile terminal. In that case, the mobile terminal processes the received sensor data using application software installed on itself.

The data acquisition device 11 is realized by, for example, an inertial measurement device including an acceleration sensor and an angular velocity sensor. An example of the inertial measurement device is an IMU (Inertial Measurement Unit). The IMU includes a three-axis acceleration sensor and a three-axis angular velocity sensor. Examples of the inertial measurement device include a VG (Vertical Gyro), an AHRS (Attitude Heading Reference System ), and a GPS/INS (Global Positioning System/Inertial Navigation System).

2 is a conceptual diagram showing an example of arranging the data acquisition device 11 in the left and right shoes 100. In the example of FIG. 2, the data acquisition device 11 is arranged at a position that hits the back side of the arch of the left and right feet. In this embodiment, the data acquisition device 11 produced with the same specifications is arranged in the left and right shoes 100 regardless of left and right. The up and down orientation (Z-axis direction orientation) of the data acquisition device 11 arranged in the left and right shoes 100 is assumed to be the same orientation. Therefore, the axes set for the sensor data derived from the left foot and the sensor data derived from the right foot are common to the left and right. In the example of FIG. 2, a local coordinate system including an x-axis in the left-right direction, a y-axis in the front-back direction, and a z-axis in the up-down direction is set in the data acquisition device 11. The x-axis is positive to the left, the y-axis is positive to the rear, and the z-axis is positive upward. The directions of the axes set in the data acquisition device 11 are not limited to the example of FIG. 2 as long as they are the same for the left and right feet.

For example, the data acquisition device 11 is disposed in an insole inserted into the shoe 100. For example, the data acquisition device 11 is disposed on the bottom surface of the shoe 100. For example, the data acquisition device 11 is embedded in the body of the shoe 100. The data acquisition device 11 may be detachable from the shoe 100, or may not be detachable from the shoe 100. Note that the data acquisition device 11 may be disposed in a position other than the back of the arch of the foot, as long as it can acquire sensor data related to foot movement. The data acquisition device 11 may also be installed in socks worn by the user, or in an accessory such as an anklet worn by the user. The data acquisition device 11 may also be attached directly to the foot or embedded in the foot.

FIG. 3 shows the local coordinate system (x-axis, y-axis, z-axis) set in the data acquisition device 11 and the world set with respect to the ground when the data acquisition device 11 is installed on the back side of the foot arch. FIG. 2 is a conceptual diagram for explaining a coordinate system (X-axis, Y-axis, Z-axis). In the world coordinate system (X-axis, Y-axis, Z-axis), when the user is standing upright, the user's side direction is the X-axis direction (facing the left is positive), and the direction of the user's back is the Y-axis direction (facing backwards is positive) , the gravity direction is set to the Z-axis direction (vertically upward is positive). In this embodiment, a local coordinate system consisting of an x direction, a y direction, and a z direction with the data acquisition device 11 as a reference is set.

Figure 4 is a conceptual diagram for explaining the planes (also called human body planes) set for the human body. In this embodiment, a sagittal plane that divides the body into left and right, a coronal plane that divides the body into front and back, and a horizontal plane that divides the body horizontally are defined. In the upright state as shown in Figure 4, the world coordinate system and the local coordinate system coincide. In this embodiment, the rotation in the sagittal plane with the x-axis as the rotation axis is defined as roll, the rotation in the coronal plane with the y-axis as the rotation axis is defined as pitch, and the rotation in the horizontal plane with the z-axis as the rotation axis is defined as yaw. In addition, the rotation angle in the sagittal plane with the x-axis as the rotation axis is defined as roll angle, the rotation angle in the coronal plane with the y-axis as the rotation axis is defined as pitch angle, and the rotation angle in the horizontal plane with the z-axis as the rotation axis is defined as yaw angle.

In this embodiment, when looking at the body from behind, counterclockwise rotation in the coronal plane is positive and clockwise rotation in the coronal plane is negative. Regarding rotation in the coronal plane with the y-axis as the rotation axis, rotation toward the thumb side is defined as abduction, and rotation toward the little finger side is defined as adduction. Regarding the right foot, when looking at the body from behind, counterclockwise rotation in the coronal plane (positive) is abduction, and clockwise rotation in the coronal plane (negative) is adduction. Regarding the left foot, when looking at the body from behind, counterclockwise rotation in the coronal plane (negative) is adduction, and clockwise rotation in the coronal plane (negative) is abduction.

FIG. 5 is a conceptual diagram for explaining the one-step cycle based on the right foot. The one-step cycle based on the left foot is also the same as that for the right foot. The horizontal axis in Figure 5 is the normalized gait cycle, with one gait cycle of the right foot starting from when the heel of the right foot hits the ground and ending when the heel of the right foot hits the ground as 100%. It is. A walking cycle of one leg is roughly divided into a stance phase, in which at least a portion of the sole of the foot is in contact with the ground, and a swing phase, in which the sole of the foot is separated from the ground. The stance phase is further subdivided into early stance T1, middle stance T2, final stance T3, and early swing T4. The swing phase is further subdivided into early swing phase T5, middle swing phase T6, and final swing phase T7.

Figure 5 (a) shows an event where the heel of the right foot touches the ground (heel strike) (HS: Heel Strike). Figure 5 (b) shows an event where the toe of the left foot leaves the ground (opposite toe off) while the sole of the right foot is on the ground (OTO: Opposite Toe Off). Figure 5 (c) shows an event where the heel of the right foot rises (heel rise) while the sole of the right foot is on the ground (HR: Heel Rise). Figure 5 (d) shows an event where the heel of the left foot touches the ground (opposite heel strike) (OHS: Opposite Heel Strike). Figure 5 (e) shows an event where the toe of the right foot leaves the ground (toe off) while the sole of the left foot is on the ground (TO: Toe Off). (f) of Fig. 5 shows an event where the left foot and the right foot cross (foot crossing) with the sole of the left foot touching the ground (FA: Foot Adjacent). (g) of Fig. 5 shows an event where the tibia of the right foot is almost perpendicular to the ground (TV: Tibia Vertical) with the sole of the left foot touching the ground. (h) of Fig. 5 shows an event where the heel of the right foot touches the ground (heel strike) (HS: Heel Strike). (h) of Fig. 5 corresponds to the end point of the walking cycle that starts from (a) of Fig. 5 and corresponds to the starting point of the next walking cycle.

The discrimination device 12 acquires sensor data related to the movement of the user's feet. The discrimination device 12 generates a waveform (also called a walking waveform) based on the time series data of the acquired sensor data. The discrimination device 12 detects the timing of heel strike from the generated walking waveform, and extracts a walking waveform for one step cycle starting from the timing of heel strike. The discrimination device 12 detects the timing of toe lift from the walking waveform of the extracted one step cycle. The discrimination device 12 determines whether the walking waveform originates from the left or right foot based on the pitch angle at the timing of heel strike and toe lift. How to determine whether the walking waveform originates from the left or right foot will be described later.

FIG. 6 is a conceptual diagram showing an example of the trajectory of the center of pressure (COP), which is the center point of the distribution of force acting on the contact surface between the ground and the sole of the foot, in a normal walking state. During the stance phase of normal walking, after the heel (A) touches the ground, the COP transitions in a curve from the little finger side (B) to the thumb side (C) of the stepping part, and leaves the ground from the thumb (D). . When the COP transitions from the little finger side (B) to the big toe side (C) of the stepping part, the posture of the sole gradually rotates (abducts) toward the big toe side. Generally, after the toe takes off, the foot continues to perform an abduction motion for a while due to inertia, so the peak of the rotation angle (pitch angle) in the coronal plane appears after the timing of the toe off.

[Data acquisition device]
Next, details of the data acquisition device 11 will be described with reference to the drawings. FIG. 7 is a block diagram showing an example of a detailed configuration of the data acquisition device 11. The data acquisition device 11 has an acceleration sensor 111, an angular velocity sensor 112, a control unit 113, and a data transmission unit 115. The data acquisition device 11 also includes a power source (not shown). In the following, the acceleration sensor 111, the angular velocity sensor 112, the control unit 113, and the data transmission unit 115 will each be described as an operating subject, but the data acquisition device 11 may be considered as an operating subject.

The acceleration sensor 111 is a sensor that measures acceleration in three axial directions (also called spatial acceleration). The acceleration sensor 111 outputs the measured acceleration to the control unit 113. For example, the acceleration sensor 111 may be a piezoelectric type, a piezo-resistive type, a capacitance type, or other type of sensor. Note that there are no limitations on the measurement method of the sensor used for the acceleration sensor 111 as long as it can measure acceleration.

Angular velocity sensor 112 is a sensor that measures angular velocity (also called spatial angular velocity) in three axial directions. Angular velocity sensor 112 outputs the measured angular velocity to control unit 113. For example, a vibration type, a capacitance type, or other type of sensor can be used for angular velocity sensor 112. Note that there are no limitations on the measurement method of the sensor used for angular velocity sensor 112 as long as it can measure angular velocity.

The control unit 113 acquires acceleration and angular velocity in three axial directions from each of the acceleration sensor 111 and the angular velocity sensor 112. The control unit 113 converts the acquired acceleration and angular velocity into digital data, and outputs the converted digital data (also referred to as sensor data) to the data transmitting unit 115. Sensor data includes acceleration data (including 3-axis acceleration vectors) obtained by converting analog data acceleration into digital data, and angular velocity data (including 3-axis angular velocity vectors) obtained by converting analog data angular velocity into digital data. ). Note that the acceleration data and the angular velocity data are associated with the acquisition time of those data. Further, the control unit 113 may be configured to output sensor data obtained by adding corrections such as mounting error, temperature correction, linearity correction, etc. to the acquired acceleration data and angular velocity data. Further, the control unit 113 may generate angle data in three axial directions using the acquired acceleration data and angular velocity data.

For example, the control unit 113 is a microcomputer or microcontroller that performs overall control of the data acquisition device 11 and data processing. For example, the control unit 113 has a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory, etc. The control unit 113 controls the acceleration sensor 111 and the angular velocity sensor 112 to measure angular velocity and acceleration. For example, the control unit 113 performs A/D conversion (Analog-to-Digital Conversion) of physical quantities (analog data) such as the measured angular velocity and acceleration, and stores the converted digital data in a flash memory. Note that the physical quantities (analog data) measured by the acceleration sensor 111 and the angular velocity sensor 112 may be converted into digital data in each of the acceleration sensor 111 and the angular velocity sensor 112. The digital data stored in the flash memory is output to the data transmission unit 115 at a predetermined timing.

The data transmitter 115 acquires sensor data from the controller 113. The data transmitter 115 transmits the acquired sensor data to the discrimination device 12. The data transmitter 115 may transmit the sensor data to the discriminating device 12 via a wire such as a cable, or may transmit the sensor data to the discriminating device 12 via wireless communication. For example, the data transmitter 115 is configured to transmit sensor data to the discrimination device 12 via a wireless communication function (not shown) that conforms to standards such as Bluetooth (registered trademark) or WiFi (registered trademark). . Note that the communication function of the data transmitter 115 may conform to standards other than Bluetooth (registered trademark) and WiFi (registered trademark).

[Detection device]
Next, details of the discrimination device 12 will be described with reference to the drawings. Fig. 8 is a block diagram showing an example of the configuration of the discrimination device 12. The discrimination device 12 has a waveform generating section 121, a detecting section 123, and a discriminating section 125.

The waveform generation unit 121 acquires sensor data from the data acquisition device 11 (sensor) installed on footwear worn by a pedestrian. The waveform generation unit 121 uses the sensor data to generate time-series data (also referred to as a walking waveform) accompanying the walk of a pedestrian wearing footwear in which the data acquisition device 11 is installed. The waveform generation unit 121 extracts a walking waveform corresponding to one step cycle from the generated walking waveform.

For example, the waveform generation unit 121 generates time series data such as spatial acceleration and spatial angular velocity. Further, the waveform generation unit 121 integrates the spatial acceleration and the spatial angular velocity, and generates time series data such as the spatial velocity, the spatial angle (plantar angle), and the spatial trajectory. The waveform generation unit 121 generates time series data at predetermined timing and time intervals set according to a general walking cycle or a walking cycle specific to the user. The timing at which the waveform generation unit 121 generates time series data can be set arbitrarily. For example, the waveform generation unit 121 is configured to continue generating time-series data while the user continues to walk. Further, the waveform generation unit 121 may be configured to generate time series data at a specific time.

The detection unit 123 detects the timing of heel contact of a pedestrian walking wearing footwear in which the data acquisition device 11 is implemented, from the walking waveform generated by the waveform generation unit 121. For example, the detection unit 123 detects the timing of heel contact based on the rotation angle (pitch angle) in the sagittal plane with the x-axis as the rotation axis. A positive peak and a negative peak appear in the walking waveform of the roll angle for one walking cycle. The detection unit 123 detects one of these peaks as the timing of heel contact and the other as the timing of toe off. The positive and negative peaks at the timing of heel contact and toe off are opposite for the left and right feet. Usually, the absolute value of the roll angle at the timing of toe off is larger than the absolute value of the roll angle at the timing of heel contact. Therefore, the detection unit 123 detects the smaller absolute value of the positive and negative peaks appearing in the walking waveform as heel contact.

The detection unit 123 extracts a walking waveform for one step cycle starting from the timing of heel strike. The detection unit 123 detects the timing of toe-off from the walking waveform for one step cycle. For example, the detection unit 123 detects the timing of heel-off based on the rotation angle (roll angle) in the sagittal plane with the x-axis as the rotation axis. The detection unit 123 detects the positive or negative peak with the larger absolute value as the toe-off from the walking waveform.

The discrimination unit 125 calculates the difference between the peak value of the rotation angle (pitch angle) in the coronal plane at the timing of toe-off and the peak value of the pitch angle at the timing of heel-off. The discrimination unit 125 determines whether the walking waveform originates from the left or right foot based on the sign (positive or negative) of the difference between the peak value of the pitch angle at the timing of heel-off and the peak value of the pitch angle at the timing of toe-off. In other words, the discrimination unit 125 determines whether the walking waveform originates from the left or right foot based on the magnitude relationship between the peak value of the pitch angle at the timing of heel-off and the peak value of the pitch angle at the timing of toe-off. For example, the discrimination unit 125 attaches a label indicating whether the data originates from the left or right foot to the walking waveform or data such as sensor data from which the walking waveform was obtained. For example, the discrimination unit 125 outputs the data to which a label indicating whether it is the left or right foot is attached to a system or device not shown. For example, the data to which the label is assigned by the discrimination unit 125 is accumulated in a database (not shown) and utilized as big data.

Figure 9 shows an example of the rotation angle (pitch angle) in the coronal plane and the rotation angle (roll angle) in the sagittal plane for one gait cycle. The pitch angle of the right foot is shown by a solid line, the pitch angle of the left foot by a dashed line, and the roll angle of the right or left foot by a dotted line. The roll angles of the left and right feet are in a similar relationship. Therefore, the positive and negative roll angles of the left and right feet match, so the waveform for either the left or right foot is shown.

The pitch angle of the right foot has a negative value at the timing of heel contact, and a positive value at the timing of toe liftoff. Therefore, regarding the right foot, the sign of the difference between the peak value (positive) at the timing of toe-off and the peak value (negative) at the timing of heel contact is positive. That is, if the difference between the peak value at the timing of toe-off and the peak value at the timing of heel-contact is positive, the determining unit 125 determines that the walking waveform originates from the right foot.

On the other hand, the pitch angle of the left foot has a positive value at the timing of heel contact, and a negative value at the timing of toe liftoff. Therefore, regarding the left foot, the sign of the difference between the peak value (negative) at the timing of toe-off and the peak value (positive) at the timing of heel contact is negative. That is, when the difference between the peak value at the timing of toe-off and the peak value at the timing of heel-contact is negative, the determining unit 125 determines that the walking waveform originates from the left foot.

(motion)
Next, the operation of the discrimination device 12 of the discrimination system 1 of this embodiment will be explained with reference to the drawings. FIG. 10 is a flowchart for explaining the outline of the operation of the discriminating device 12. The details of the operation of the discriminating device 12 are as described above regarding the configuration.

In FIG. 10, first, the discrimination device 12 detects heel contact from time series data (also called walking waveform) generated from sensor data regarding physical quantities related to foot movement, and detects heel contact for one step period starting from heel contact. A walking waveform is extracted (step S11).

Next, the discrimination device 12 detects toe-off from the walking waveform for one step cycle (step S12).

Next, the discrimination device 12 calculates the pitch angle at the timing of heel contact and toe off (step S13).

Next, the determination device 12 calculates the difference in pitch angles at the timings of heel contact and toe takeoff (step S14). The determination device 12 calculates a difference in pitch angles by subtracting the pitch angle at the timing of heel contact from the pitch angle at the timing of toe-off.

Next, the discrimination device 12 determines whether the gait waveform under verification is the gait waveform of the right or left foot based on the sign (positive or negative) of the pitch angle difference (step S15). If the pitch angle difference is positive, the discrimination device 12 determines that the gait waveform under verification originates from the right foot. If the pitch angle difference is negative, the discrimination device 12 determines that the gait waveform under verification originates from the left foot.

Next, the discrimination device 12 attaches a label to the gait data including the gait waveform being verified, indicating whether the foot from which the data is acquired is the left or right leg (step S16). For example, the discrimination device 12 outputs the labeled gait data to a system or device (not shown). For example, the data output from the discrimination device 12 is accumulated in a database (not shown) and utilized as big data.

As described above, the discrimination system of this embodiment includes a data acquisition device and a discrimination device. The data acquisition device measures spatial acceleration and spatial angular velocity, generates sensor data based on the measured spatial acceleration and spatial angular velocity, and transmits the generated sensor data to the estimation device. The discrimination device includes a waveform generation section, a detection section, and a discrimination section. The waveform generation unit generates a walking waveform using sensor data related to foot movement. The detection unit detects the timing of heel contact and toe separation from the walking waveform of the rotation angle in the sagittal plane. The determining unit determines whether the walking waveform is derived from the data of the left or right foot, based on the characteristics of the walking waveform of the rotation angle in the coronal plane at the timing of heel contact and toe liftoff. For example, the determination unit assigns a label to data related to the walking waveform according to the result of the discrimination of the walking waveform.

Generally, the left and right feet are mirror images in the coronal plane, making it difficult to determine which foot the acquired walking waveform originates from. According to this embodiment, the difference between the left and right feet can be detected from the walking waveform characteristics of the rotation angle in the coronal plane at the timing of heel contact and toe lift. Therefore, according to the discrimination device of this embodiment, it is possible to determine which foot the walking waveform originates from, based on the data measured by sensors attached to the left and right feet.

In one aspect of this embodiment, the waveform generating unit extracts a walking waveform for one step cycle from the walking waveform. The discriminator discriminates whether the walking waveform originates from the left or right foot based on the peak value of the walking waveform of the rotation angle in the coronal plane for one step cycle. For example, the discriminator discriminates whether the walking waveform originates from the left or right foot based on the magnitude relationship between the peak value of the rotation angle in the coronal plane at the timing of heel contact and the peak value of the rotation angle in the coronal plane at the timing of toe off. For example, the discriminator discriminates whether the walking waveform originates from the left or right foot based on the sign of the value obtained by subtracting the peak value of the rotation angle in the coronal plane at the timing of heel contact from the peak value of the rotation angle in the coronal plane at the timing of toe off. According to this aspect, it is possible to discriminate whether the walking waveform originates from the left or right foot based on the relationship between the peak values of the rotation angle in the coronal plane.

Second Embodiment
Next, a discrimination device according to a second embodiment will be described with reference to the drawings. The discrimination device of this embodiment differs from the discrimination device of the first embodiment in that the discrimination device analyzes gaits using discrimination results. In the following, detailed descriptions of the same parts as those of the first embodiment will be omitted.

(composition)
FIG. 11 is a block diagram showing the configuration of the discrimination system 2 of this embodiment. The discrimination system 2 includes a data acquisition device 21 and a discrimination device 22. The data acquisition device 21 and the discrimination device 22 may be connected by wire or wirelessly. The data acquisition device 21 and the discrimination device 22 may be configured as a single device. In addition, the discrimination system 2 may be configured only by the discrimination device 22, excluding the data acquisition device 21 from the configuration of the discrimination system 2. Note that only one data acquisition device 21 is illustrated in FIG. 11, but in this embodiment, one data acquisition device 21 is arranged in correspondence with each of the left and right feet (two in total). The data acquisition device 21 has the same configuration as the data acquisition device 11 of the first embodiment. In the following, the discrimination device 22 different from the first embodiment will be described, focusing on the differences from the first embodiment.

[Discrimination device]
FIG. 12 is a block diagram showing an example of the configuration of the discrimination device 22 of this embodiment. The discrimination device 22 includes a waveform generation section 221, a detection section 223, a discrimination section 225, a storage section 227, and an analysis section 229. The waveform generating section 221, the detecting section 223, and the discriminating section 225 are the same as the corresponding configurations of the discriminating device 12 of the first embodiment, so a detailed explanation will be omitted.

The storage unit 227 stores an analysis model for analyzing the walking waveform included in the output data of the discrimination device 22. The analysis model includes an algorithm for analyzing the gait based on the gait waveform. An analytical model is constructed for each of the left and right feet. Note that if the same algorithm can be used for the left and right feet, a common analysis model may be constructed for both the left and right feet. Examples of analytical models are listed below, but the analytical models stored in the storage unit 227 of this embodiment are not limited to the following examples.

For example, the analytical model includes an algorithm for extracting a gait waveform for one walking cycle based on the gait waveform. For example, the analytical model is a model that uses the gait waveform of the plantar angle to detect the center time of each successive stance phase and extracts the waveform between the detected times as a gait waveform for one gait cycle. For example, the analytical model includes an algorithm for detecting the stance phase and the swing phase based on the gait waveform. For example, the analytical model is a model that extracts the timing of toe-off detected from the gait waveform of the forward acceleration as the starting point of the swing phase, and extracts the timing of heel-contact detected from the forward acceleration and height acceleration as the starting point of the stance phase.

For example, the analytical model includes an algorithm for identifying walking events based on the walking waveform. For example, the analytical model is a model that detects walking events such as toe-off, heel-on, opposite foot heel-on, opposite foot toe-off, tibia vertical, foot crossing, and heel-up based on features extracted from the walking waveform for one step cycle. For example, the analytical model includes an algorithm for identifying the step length of each of the left and right feet based on the walking waveform. For example, the analytical model is a model that extracts the walking waveform of the forward direction trajectory of one step from the walking waveform of the forward direction trajectory of one step cycle, and calculates the step length of each of the left and right feet based on the timing of foot crossing. For example, the analytical model includes an algorithm for estimating the symmetry of walking based on the walking waveform. For example, the analytical model is a model that generates walking waveforms of the posture angles of each of the left and right feet using spatial acceleration or spatial angular velocity, and estimates the symmetry of walking based on the symmetry of walking parameters calculated using the extreme values of the peaks appearing in the walking waveforms of the posture angles of each of the left and right feet. For example, the analytical model includes an algorithm for analyzing the trajectory of foot swing during walking based on a gait waveform.

For example, the analytical model includes an algorithm for detecting foot abnormalities, such as the progression of a hallux valgus, based on the gait waveform. For example, the analysis model extracts characteristic gait features of pedestrians wearing footwear, and detects abnormalities in the feet of pedestrians wearing footwear based on the extracted gait features. It's a model. For example, the analytical model includes an algorithm for estimating the degree of pronation/supination of the foot based on the gait waveform. For example, the analysis model is a model that estimates the degree of pronation/supination of the foot using feature amounts extracted from the angle waveform in the coronal plane at the end of stance. For example, the analytical model includes an algorithm for estimating the degree of internal/external rotation of the foot based on the walking waveform. For example, the analysis model uses the foot velocity vector and posture angle to calculate the foot angle, which is the angle between the velocity vector and the center line of the foot, and based on the calculated foot angle, internal rotation/external rotation of the foot. This is a model for estimating the degree of rotation.

The analysis unit 229 acquires the output data of the determination unit 225. The output data includes a walking waveform with a label indicating whether the foot is the left or right foot. The analysis unit 229 applies the analysis model stored in the storage unit 227 to the acquired output data to analyze the walking waveform. For example, the analysis unit 229 outputs the analysis results to a system or device (not shown). For example, data output from the analysis unit 229 is accumulated in a database (not shown) and utilized as big data.

Figure 13 is a conceptual diagram showing an example of displaying the analysis results by the analysis unit 229 of the discrimination device 22 on the display unit of a terminal device 260 carried by a user walking while wearing footwear 200 equipped with a data acquisition device 21. Figure 13 shows an example of analyzing the walking waveform accumulated while the user is walking using an analytical model that analyzes the degree of pronation/supination of the foot.

For example, the analysis unit 229 outputs an analysis result indicating that the walking waveform of the left foot is measured by the sensor 1 and that the degree of pronation/supination of the left foot is within the normal range. Furthermore, the analysis unit 229 outputs an analysis result indicating that the walking waveform of the right foot is measured by the sensor 2 and that the degree of pronation/supination of the right foot is within the normal range. For example, the display of the terminal device 260 carried by the user may display messages such as "The degree of pronation/supination of the left foot (sensor 1) is within the normal range" and "The degree of pronation/supination of the right foot (sensor 2)". Information such as "The degree of damage is outside the normal range" is displayed. The user who confirms the information displayed on the display section of the terminal device 260 can recognize the degree of pronation/supination of his/her left and right feet while walking. For example, if the degree of pronation/supination is abnormal, a message recommending seeing a doctor at a hospital or contact information for an appropriate hospital may be displayed on the display section of the terminal device 260.

The example in FIG. 13 is an example, and does not limit the method of using the analysis result by the discrimination device of this embodiment. For example, information regarding the gait, such as the step length of the left and right legs, the locus of the whirling, symmetry, and foot angle, may be displayed on the display unit of the terminal device 260. For example, information regarding the progress status of hallux valgus on the left and right feet may be displayed on the display unit of the terminal device 260. For example, based on a walking waveform measured while walking, a warning sound, vibration, or the like may be used to notify that the right and left footwear are incorrect. If a child or elderly person continues to walk with their footwear on the wrong side, there is a risk of falling, but such risks may be avoided if they are notified that their footwear is on the wrong side. be.

(motion)
Next, the operation of the discrimination device 22 of the discrimination system 2 of this embodiment will be explained with reference to the drawings. FIG. 14 is a flowchart for explaining the outline of the operation of the discrimination device 22. The details of the operation of the discrimination device 22 are as described above regarding the configuration.

In FIG. 14, first, the discrimination device 22 detects heel contact from time series data (also called walking waveform) generated from sensor data regarding physical quantities related to foot movement, and detects heel contact for one step period starting from heel contact. A walking waveform is extracted (step S21).

Next, the discrimination device 22 detects toe-off from the walking waveform for one step cycle (step S22).

Next, the discrimination device 22 calculates the pitch angle at the timing of heel contact and toe off (step S23).

Next, the discrimination device 22 calculates the difference in pitch angle between the timing of heel contact and the timing of toe off (step S24). The discrimination device 22 calculates the difference in pitch angle as the value obtained by subtracting the pitch angle at the timing of heel contact from the pitch angle at the timing of toe off.

Next, the determining device 22 determines which foot, left or right, the walking waveform under verification corresponds to, based on the sign (positive or negative) of the pitch angle difference (step S25). If the pitch angle difference is positive, the determining device 22 determines that the walking waveform under verification originates from the right foot. If the pitch angle difference is negative, the determination device 22 determines that the walking waveform under verification originates from the left foot. For example, the discrimination device 22 attaches a label to the gait waveform under verification indicating which leg, the left or the right, the gait waveform originates from.

If the gait waveform originates from the left foot (Yes in step S26), the discrimination device 22 analyzes the gait using an analytical model for the left foot (step S27). On the other hand, if the walking waveform originates from the right foot (No in step S26), the discrimination device 22 analyzes the gait using the analysis model for the right foot (step S28).

Then, the discrimination device 22 outputs the analysis result in step S27 or step S28 (step S29). For example, the analysis results by the discriminator 22 are displayed on the display of a terminal device (not shown), output to a system (not shown) that uses the analysis results, or output to a database (not shown) that stores the analysis results. Sometimes it happens.

As described above, the discrimination system of this embodiment includes a data acquisition device and a discrimination device. The data acquisition device measures spatial acceleration and spatial angular velocity, generates sensor data based on the measured spatial acceleration and spatial angular velocity, and transmits the generated sensor data to the estimation device. The discrimination device includes a waveform generation section, a detection section, a discrimination section, a storage section, and an analysis section. The waveform generation unit generates a walking waveform using sensor data related to foot movement. The detection unit detects the timing of heel contact and toe separation from the walking waveform of the rotation angle in the sagittal plane. The determining unit determines whether the walking waveform is derived from the data of the left or right foot, based on the characteristics of the walking waveform of the rotation angle in the coronal plane at the timing of heel contact and toe liftoff. The storage unit stores an analysis model for analyzing the gait of each of the left and right legs based on the gait waveform of each of the left and right legs. The analysis unit uses the analysis model to analyze the gait of each of the left and right feet based on the gait waveform of each of the left and right feet. For example, the analysis unit outputs information according to the analysis results regarding the gait of each of the left and right feet.

In this embodiment, the gait of each left and right foot can be analyzed by using separate analytical models for each foot.

(The third implementation system)
Next, a discrimination device according to a third embodiment will be described with reference to the drawings. The discrimination device of this embodiment has a simplified configuration of the discrimination device of each embodiment. Fig. 15 is a block diagram showing an example of the configuration of a discrimination device 32 of this embodiment. The discrimination device 32 includes a waveform generating unit 321, a detecting unit 323, and a discriminating unit 325.

The waveform generation unit 321 generates a walking waveform using sensor data related to foot movements. The detection unit 323 detects the timing of heel contact and toe separation from the walking waveform of the rotation angle in the sagittal plane. The determining unit 325 determines whether the walking waveform is derived from the data of the left or right foot, based on the characteristics of the walking waveform of the rotation angle in the coronal plane at the timing of heel contact and toe liftoff.

The discrimination device according to the present embodiment can detect the difference between the left and right feet from the characteristics of the walking waveform of the rotation angle in the coronal plane at the timing of heel contact and toe liftoff. Therefore, the discrimination device of this embodiment can discriminate from which foot a walking waveform originates, the left or right foot, based on the data measured by the sensors attached to the left and right feet.

(hardware)
Here, a hardware configuration for executing the processing of the discrimination device according to each embodiment of the present disclosure will be described using an information processing device 90 in Fig. 16 as an example. Note that the information processing device 90 in Fig. 16 is an example of a configuration for executing the processing of the discrimination device according to each embodiment, and does not limit the scope of the present disclosure.

As shown in FIG. 16, the information processing device 90 includes a processor 91, a main memory device 92, an auxiliary memory device 93, an input/output interface 95, and a communication interface 96. In FIG. 16, the interface is abbreviated as I/F (Interface). The processor 91, the main memory device 92, the auxiliary memory device 93, the input/output interface 95, and the communication interface 96 are connected to each other via a bus 98 so as to be able to communicate data with each other. In addition, the processor 91, the main memory device 92, the auxiliary memory device 93, and the input/output interface 95 are connected to a network such as the Internet or an intranet via the communication interface 96.

The processor 91 deploys a program stored in the auxiliary storage device 93 or the like in the main storage device 92 and executes the deployed program. In this embodiment, a software program installed in the information processing device 90 may be used. The processor 91 executes processing by the discrimination device according to this embodiment.

The main storage device 92 has an area where programs are expanded. The main storage device 92 may be, for example, a volatile memory such as DRAM (Dynamic Random Access Memory). Furthermore, a non-volatile memory such as MRAM (Magnetoresistive Random Access Memory) may be configured or added as the main storage device 92.

The auxiliary storage device 93 stores various data. The auxiliary storage device 93 is configured with a local disk such as a hard disk or flash memory. It is also possible to store various data in the main storage device 92 and omit the auxiliary storage device 93.

The input/output interface 95 is an interface for connecting the information processing device 90 to peripheral devices. The communication interface 96 is an interface for connecting to external systems or devices through a network such as the Internet or an intranet based on standards and specifications. The input/output interface 95 and the communication interface 96 may be shared as an interface for connecting to external devices.

The information processing device 90 may be configured to connect input devices such as a keyboard, mouse, or touch panel as necessary. These input devices are used to input information and settings. When a touch panel is used as an input device, the display screen of the display device may be configured to also function as an interface for the input device. Data communication between the processor 91 and the input devices may be mediated by the input/output interface 95.

The information processing device 90 may also be equipped with a display device for displaying information. When a display device is equipped, it is preferable that the information processing device 90 is equipped with a display control device (not shown) for controlling the display of the display device. The display device may be connected to the information processing device 90 via the input/output interface 95.

Further, the information processing device 90 may be equipped with a drive device. The drive device mediates between the processor 91 and a recording medium (program recording medium), reading data and programs from the recording medium, writing processing results of the information processing device 90 to the recording medium, and the like. The drive device may be connected to the information processing device 90 via the input/output interface 95.

The above is an example of the hardware configuration for realizing the discrimination device according to each embodiment of the present invention. Note that the hardware configuration in FIG. 16 is an example of a hardware configuration for executing the arithmetic processing of the discrimination device according to each embodiment, and does not limit the scope of the present invention. Further, a program that causes a computer to execute processing related to the discrimination device according to each embodiment is also included within the scope of the present invention. Furthermore, a program recording medium on which a program according to each embodiment is recorded is also included within the scope of the present invention. The recording medium can be realized by, for example, an optical recording medium such as a CD (Compact Disc) or a DVD (Digital Versatile Disc). Further, the recording medium may be realized by a semiconductor recording medium such as a USB (Universal Serial Bus) memory or an SD (Secure Digital) card, a magnetic recording medium such as a flexible disk, or other recording media. When a program executed by a processor is recorded on a recording medium, the recording medium corresponds to a program recording medium.

The components of the discrimination device of each embodiment can be arbitrarily combined. Further, the components of the discrimination device of each embodiment may be realized by software or by a circuit.

Although the present invention has been described above with reference to the embodiments, the present invention is not limited to the above-mentioned embodiments. Various modifications that can be understood by a person skilled in the art can be made to the configuration and details of the present invention within the scope of the present invention.

1, 2 Discrimination system 11, 21 Data acquisition device 12, 22 Discrimination device 111 Acceleration sensor 112 Angular velocity sensor 113 Control section 115 Data transmission section 121, 221, 321 Waveform generation section 123, 223, 323 Detection section 125, 225, 325 Discrimination Section 227 Storage section 229 Analysis section

Claims (10)

A waveform generating means for generating a walking waveform using sensor data relating to foot movement;
A detection means for detecting the timing of heel contact and toe lift from a walking waveform of a rotation angle in a sagittal plane;
and a discrimination means for discriminating whether the gait waveform is derived from data of the left or right foot based on characteristics of the gait waveform of the rotation angle in the coronal plane at the timing of the heel contact and the toe off. The waveform generating means includes:
Extracting a walking waveform for one step period from the walking waveform,
The discrimination means is
2. The determination device according to claim 1, which determines from which leg, the left or right, the walking waveform originates from, based on the peak value of the walking waveform of the rotation angle in the coronal plane for one walking cycle. The discrimination means is
3. The discrimination device according to claim 1, which discriminates whether the walking waveform originates from the left or right foot based on a magnitude relationship between a peak value of the rotation angle in the coronal plane at the timing of the heel contact and a peak value of the rotation angle in the coronal plane at the timing of the toe off. The discrimination means is
4. The discrimination device according to claim 1, wherein the discrimination device discriminates whether the gait waveform originates from the left or right foot based on a sign of a value obtained by subtracting a peak value of the rotation angle in the coronal plane at the timing of the heel contact from a peak value of the rotation angle in the coronal plane at the timing of the toe off. The discrimination means is
The discrimination device according to claim 1 , further comprising: a label corresponding to a discrimination result of the gait waveform, the label being assigned to data relating to the gait waveform. a storage means for storing an analytical model for analyzing the gait of each of the left and right feet based on the walking waveforms of each of the left and right feet;
5. The discrimination device according to claim 1, further comprising: analysis means for analyzing the gait of each of the left and right feet based on the walking waveforms of each of the left and right feet by using the analysis model. The analysis means
7. The discrimination device according to claim 6, which outputs information corresponding to the analysis results relating to the gait of each of the left and right legs. The discrimination device according to any one of claims 1 to 7,
A discrimination system comprising: a data acquisition device that is placed on each of a pair of footwear worn by a user whose walking waveform is to be measured, measures spatial acceleration and spatial angular velocity in accordance with the user's walking, generates sensor data based on the measured spatial acceleration and spatial angular velocity, and transmits the generated sensor data to the discrimination device. The computer is
Generates a walking waveform using sensor data related to foot movements,
The timing of heel contact and toe release is detected from the walking waveform of the rotation angle in the sagittal plane.
A determination method for determining whether the walking waveform under verification is derived from data of the right or left foot, based on the characteristics of the walking waveform of the rotation angle in the coronal plane at the timing of the heel contact and the toe liftoff. A process of generating a walking waveform using sensor data related to foot movement;
A process for detecting the timing of heel contact and toe off from a walking waveform of the rotation angle in the sagittal plane;
and determining whether the gait waveform being verified originates from data of the left or right foot based on the characteristics of the gait waveform of the rotation angle in the coronal plane at the timing of the heel contact and the toe off .

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