KR20200008973A - Wearable Type Lower Body Motion Information Collecting Device - Google Patents

Abstract

The present invention relates to a wearable type lower body motion information collecting device. More specifically, the present invention relates to a wearable type lower body motion information collecting device which can provide basic data for analyzing walking characteristics and intentions for various lower body motions of a wearer through precise multi-axis motion angle measurement of lower body joints of the wearer without space restrictions.

Description

Wearable lower body motion information collecting device {Wearable Type Lower Body Motion Information Collecting Device}

The present invention relates to a wearable lower body motion information collecting device, and more particularly, to analyze the wearer's walking characteristics and intentions for various lower body motions through precise multi-axis movement angle measurement of the lower body joint of the wearer without any limitation of space. It relates to a wearable lower body motion information collection device that can provide basic data for.

Wearable robots have been introduced to assist the posture and movement of people with lower limb lesions due to accidents and aging and for workers carrying heavy loads. The wearable robot is mainly used as a means to assist the user's muscle strength.

Since the wearable robot should be provided on the basis of the physical condition of the wearer's body or the physical characteristics, analysis of the walking motion of the wearer should be preceded for the prescription of the robot.

To this end, it is important to check the movement of each joint of the user in various environments and to understand the motion intention. Various motion analysis methods have been introduced to understand these motion intentions. Motion analysis measures changes in the musculoskeletal structure of the human body during a specific motion, and measures information such as joint and muscle loads, joint angles of motion, rotational torque, etc. It means how information can be checked.

The conventional motion analysis apparatus uses a plurality of cameras installed in a specific space, a plurality of markers attached to a specific part of the body, a ground reaction force measuring device, and the like to walk in a space based on joint movement, rotation angle, and ground reaction force. It was configured in a way to measure.

However, the conventional method has a considerable cost in the installation of the motion analysis device, and it is difficult to measure and analyze various motions due to the spatial constraints of the motion analysis device itself. Since the coordinates must be rearranged to match coordinates, complicated signal processing is required, and thus, it is difficult to analyze motion in real life or in various environments.

In addition, the motion analysis device composed of only a plurality of Inertial Measurement Units (IMUs), which have been conventionally tried, can be attached to a specific part of the body to measure the position values of the joints in the space, but the position values of the area before and after the joint of the wearer. Since only the measurement of the joint, there is a problem that can not measure the rotation angle in the three-dimensional space of the joint because it does not reflect when there is a joint axis change depending on the torsion or physical characteristics of the joint.

In addition, the signal may be distorted due to the metal material affecting the magnetic field due to the characteristics of the inertial measurement device, and since the rotation angle of the joint is not measured, an example of accurate motion analysis may include a method of measuring the rotation angle of the joint. As it is not appropriate, related technology development is needed.

It is an object of the present invention to provide a wearable lower body motion information collection device that can provide basic data for analyzing the wearer's walking characteristics and intentions for various lower body motions through precise multi-axis movement angle measurement of the lower body joint of the wearer. .

The above-described object of the present invention is worn on the hip joint region of the wearer, a hip joint measurement unit having an encoder for detecting the rotation angle of the wearer, and worn on the knee joint region of the wearer, the rotation angle of the knee joint of the wearer Receives the rotation angle of the joint measured by the knee measuring unit and the hip joint measuring unit and the encoder of the knee measuring unit having an encoder to determine the hip joint rotation angle and knee joint angle derived by the received encoder measurement value It can be achieved by providing a wearable lower body motion information collection device comprising a control unit.

Here, the wearable lower body motion information collection device may be worn on the ankle joint region of the wearer, and may further include an ankle joint measuring unit having an encoder for detecting a rotation angle of the wearer's ankle joint.

In addition, the control unit is mounted near the waist of the wearer, and may be provided in a main body having a power supply and an external analysis device and a communication function.

On the other hand, the encoder provided in each joint is mounted to the hinge region of the bendable link member constituting the wearing portion to be worn in each joint, each of the encoder to measure the bending angle of the link member connected by the hinge Can be.

Here, at least one joint measuring unit of each joint measuring unit may further include an inertial measurement unit including a 3-axis accelerometer, a 3-axis gyroscope, and a magnetometer. The rotation angle of the joint derived as a value measured through the joint measuring unit provided with the inertial measurement unit may be an Euler angle.

In addition, the control unit uses the original number (Quaternion, q ₀ , q ₁ , q ₂ , q ₃ ) measured by the inertial measurement unit, the raw Euler angle (rolling angle (ф), pitch angle (θ) and yawing) After calculating the angle ψ, the pitch angle θ is extracted and the error angle θ _err of the extracted pitch angle θ and the measurement angle θ _enc of the encoder of the joint provided with the inertial measurement apparatus. Compensation Euler angle (rolling angle ф) of each joint by deriving the compensation matrix [R _θ ] and then compensating the original Euler angle (rolling angle ф, pitch angle θ and yaw angle ψ). '), Pitch angle [theta]' and yaw angle [psi] 'can be derived as the rotation angle of the joint.

In addition, the controller or the external analyzer may determine the position and posture of each joint in the wearer's space based on the length of the wearer's thigh and the length of the lower thigh.

According to the wearable lower body motion information collection device according to the present invention, it is possible to determine the precise movement angle through a plurality of encoder signal values mounted on the lower limb joint, and to detect the spatial multi-axis movement of the lower limb joint using a plurality of inertial measurement devices. Can be.

In addition, according to the wearable lower body motion information collection device according to the present invention, it is equipped with an inertial measurement device can grasp the overall spatial movement of the body, including before and after the joint area.

In addition, according to the wearable lower body motion information collection apparatus according to the present invention, the gimbal lock phenomenon can be prevented by the inertia measuring device to measure the spatial value by the quaternion, and then the control unit converts to the Euler angle.

In addition, according to the wearable lower body motion information collecting device according to the present invention, by correcting the Euler angle derived from the inertial measurement device to the reference value of the rotation axis of the encoder using the encoder value, it is possible to determine the exact motion and the movement position of the joint.

In addition, by using the position value corrected by the encoder value, it is possible to accurately collect the physical characteristics and motion information of the wearer.

In addition, according to the wearable lower body motion information collection device according to the present invention, it can be attached to a suit worn on the body, it is possible to perform the motion analysis in a variety of environments without the limitation of space.

In addition, according to the wearable lower body motion information collecting device according to the present invention, it is possible to measure the ground reaction force during any lower limb movement through the ground reaction sensor in the form of shoes.

In addition, according to the wearable lower body motion information collecting device according to the present invention, it is possible to grasp various intentions of the wearer, such as sitting, standing, going up and down stairs, falling.

1 (a) and 1 (b) show the overall configuration of the wearable lower body motion information collecting apparatus according to the present invention and an example in which the configuration is worn on the wearer's body.
2 illustrates a hip measurement unit of the wearable lower body motion information collecting device according to the present invention.
3 is a view illustrating a knee joint measurement unit of a wearable lower body motion information collecting device according to the present invention.
4 (a) and 4 (b) shows ankle joint measurement unit of the wearable lower body motion information collection device according to the present invention.
Figure 5 shows a configuration connected to the control unit of the wearable lower body motion information collecting apparatus according to the present invention.
6 illustrates a process of converting and compensating measurement values provided from an encoder and an inertial measurement unit of the knee joint measurement unit of the wearable lower body motion information collection device according to the present invention.
Figure 7 shows an example of the movement of the wearer of the wearable lower body motion information collecting device according to the present invention.
Figure 8 illustrates a change in the rotation angle of each joint of the wearer measured by the wearable lower body motion information collection device according to the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the embodiments described below are just described in detail enough to be easily carried out by those of ordinary skill in the art, which does not mean that the scope of protection of the present invention is limited. Do not. In describing the various embodiments of the present invention, the same reference numerals will be used for the elements having the same technical features.

1 (a) and 1 (b) show the overall configuration of the wearable lower body motion information collection apparatus according to the present invention and an example in which the configuration is worn on the wearer's body. Reference will be made to the wearable lower body motion information collecting device according to the present invention.

Wearable lower body motion information collecting device 1000 according to the present invention can be worn on the wearer's body, in detail the wearer's lower body area, the lower body of the wearer by measuring the rotation angle and position value of the joint of the worn portion It can be used to analyze the behavior of.

To this end, the wearable lower body motion information collecting device 1000 of the present invention includes a control unit 100, a hip joint measurement unit 200, a knee joint measurement unit 300, and may further include an ankle joint measurement unit 400. have.

Here, the hip joint measuring unit 200 may be worn on the hip joint region of the wearer, and the rotation angle of the hip joint, which is an angle formed by the waist part (a) and the thigh part (b) on the sagittal plane of the wearer's body, in detail. Can be detected. The rotation angle of the hip joint may be assumed to be a rotation angle based on a virtual vertical axis penetrating the sagittal plane.

In addition, the knee joint measurement unit 300 may be worn in the knee joint area of the wearer to detect an angle of rotation formed by the thighs (b) and the lower thighs (c) on the wearer's body, and the ankle joint measurement unit 400. Is worn on the ankle joint region of the wearer can detect the spatial rotation angle of the ankle joint formed by the lower leg (c) and the plantar portion (d).

The hip measurement unit 200, the knee joint measurement unit 300, and the ankle joint measurement unit 400 transmit the measured rotation angles to the control unit, and the control unit transmits the rotation angles from the respective measurement units 200, 300, and 400. By receiving it, it is possible to determine the actual rotation angle and position change value of each joint.

The controller 100 may be mounted on the wearer's body, and may be separately provided without being mounted on the wearer's body, and may be connected to each of the measurement units 200, 300, and 400 by wired or wireless communication.

As shown in FIG. 1A, the controller 100 may be provided in a main body (without reference numerals) worn near the waist of the wearer. Here, the main body may be provided in the form of a backpack, a hip section or a portable bag, and may be provided with various functions for analyzing a wearer's motion, such as a power supply and a communication function with an external analyzer.

In addition, the wearable lower body motion information collecting device 1000 according to the present invention may be mainly used to measure the rotation angle of the hip and knee joint, and further provided to measure the rotation angle and ground reaction force or plantar pressure of the ankle joint. May be

2 illustrates the hip measurement unit 200 of the wearable lower body motion information collecting apparatus 1000 according to the present invention.

Referring to the hip joint measuring unit 200 of the wearable lower body motion information collecting apparatus of the present invention, the hip joint measuring unit 200 may include a wearing unit 210, the encoder 220. In addition, the hip joint measuring unit may further include an inertial measurement unit 230 for calculating the position or Euler angle of each joint through the inertia measurement of the hip joint region together with the encoder 220. I'll explain more about this later.

The wearing portion 210 to be worn on the hip joint may be provided to surround the wearer's hip joint, and in detail, the hinge is disposed on the hip joint portion so as to be bent over the hip joint region including the hip joint. The hinge may be mounted and bent to the hinge.

The wearing part 210 may have a shape of a curved structure surrounding the waist and / or the thigh for convenience of wearing and preventing falling down.

In addition, the wearing portion 210 to be worn on the hip joint may have a material or structure that can be adjusted in elastic material or width, the body worn in the waist portion is provided in the form of a backpack, hip section or a portable bag described above. It may be coupled to and provided to support the waist portion.

The encoder 220 worn on the hip joint may be provided to measure the rotation angle of the hip joint of the wearer, and is mounted on the hinge region of the wearer 210 to measure the bending angle of the link member mounted on the hinge. The rotation angle of the hip joint of the wearer can be measured.

Here, the bending angle may also be assumed to be a rotation angle on the sagittal surface of the wearer's body.

Here, for convenience of explanation and future calculation, as illustrated in FIG. 2, an axis passing through the hip joint of the wearer and perpendicular to the sagittal plane may be set as the y axis.

Therefore, the bending angle measured by the encoder 220 may be a rotation angle of the hip joint on the sagittal plane of the wearer because the link member is bent on the hinge on the sagittal plane.

The encoder 220 worn on the wearer's hip joint may transmit the measured bending angle to the controller, and the controller 100 may receive the bending angle to determine the rotation angle of the hip joint.

On the other hand, the hip joint measuring unit 200 may be provided with an inertial measurement unit 230. The inertial measurement unit 230 provided in the hip joint measuring unit 200 may measure a rotation angle and / or a position value of the hip joint, and for this purpose, a 3-axis accelerometer and a 3-axis gyroscope And a magnetometer.

As shown in FIG. 2, the inertial measurement unit 230 is mounted on the hip joint region of the wearer and measures a rotation angle and / or a position value according to the movement of the hip joint, wherein the measured value is a quaternion , q0, q1, q2, q3).

Here, the quaternions (q0, q1, q2, q3) are used when measuring or expressing the rotational angle in space, and the quaternary number is determined by arbitrary rotation when the rotational angle of the space stroke is measured or expressed by Euler angle Coordinate system that introduces the concept of a complex number in order to prevent the so-called gimbalfall phenomenon in which arbitrary axes overlap to limit the degree of freedom or the rotation becomes meaningless. .

The number of employees q0, q1, q2, and q3 measured by the inertial measurement unit 230 is transmitted to the control unit, and the control unit 100 receives the number of employees q0, q1, q2, and q3 to obtain the original Euler angle. Can be converted to

Here, the Euler angle is a three-dimensional space is defined by the x-axis, y-axis, z-axis and the movement value of the coordinates is expressed as a rotation angle about each axis, the inertial measurement unit 230 of the hip measurement unit 200 As shown in FIG. 2, the reference axis of the Euler angle based on, sets the position of the inertial measurement unit 230 of the hip measurement unit 200 as the origin, and sets the length of the wearer's thigh in the x-axis. The reference axis may be a reference axis in which an axis perpendicular to the x-axis and penetrating the origin but perpendicular to the wearer's sagittal plane is set to a y-axis, and an axis perpendicular to both the x-axis and the y-axis.

Here, the rotation angle based on the x axis may be defined as a rolling angle (ф), the y axis based on a pitch angle (θ), and the rotation angle based on the z axis as a yaw angle (ψ). The quaternary numbers q0, q1, q2 and q3 can be converted into Euler angles by the following equations (1) to (3).

.....(식1)

..... (Equation 1)

.....(식2)

..... (Equation 2)

.....(식3)

... (Eq. 3)

Therefore, the number of employees q0, q1, q2, and q3 measured by the inertial measurement unit 230 of the hip joint measuring unit 200 is determined by the control unit 100 or an external analyzer through the original Euler angle ф. , θ, ψ), where the pitch angle θ is a rotation based on an axis perpendicular to the sagittal plane based on the inertial measurement unit 230 of the wearer's hip measurement unit 200. It is angle.

The pitch angle θ may be used later to extract a compensation matrix through comparison with the rotation angle θ _enc measured by the encoder 220 in the controller 100 or an external analyzer. The original Euler angles ф, θ, ψ may be corrected to the compensation Euler angles ф ′, θ ′, ψ ′ by the compensation matrix, which will be described later.

 3 is a view illustrating the knee joint measuring unit 300 of the wearable lower body motion information collecting apparatus 1000 according to the present invention, and the knee joint measuring unit 300 will be described.

The knee measurement unit 300 of the wearable lower body motion information collecting device 1000 of the present invention measures the movement of the knee joint of the wearer, and for this purpose, the wearing unit 310, the encoder 320, and the inertial measurement unit 330 are measured. It may include.

In detail, the wearing part 310 to be worn on the knee joint may be provided to surround the knee joint of the wearer, and in detail, the hinge is disposed on the knee joint portion so that the knee joint may be bent based on the knee joint region. A link member may be mounted and bent at the hinge.

The wearing part 310 may be configured to surround the thigh and the lower leg, respectively, for convenience of wearing and preventing the falling down, there is no inconvenience in walking, and to reduce the physical interference of the wearing part 310 and The back of the lower thigh can be curved.

The encoder 320 worn on the knee joint may be provided to measure the rotation angle of the knee joint of the wearer, by measuring the bending angle of the link member mounted on the hinge by being mounted on the hinge region of the knee joint wearing portion 310. The rotation angle of the knee joint of the wearer can be measured.

Here, the bending angle may also be assumed to be a rotation angle on the sagittal surface of the wearer's body.

Here, in order to align the reference axis of the sagittal plane in the same manner as in the above-described hip joint, as shown in FIG. 3, an axis passing through the knee joint of the wearer and perpendicular to the sagittal plane may be set as the y axis.

Therefore, the bending angle measured by the encoder 330 of the knee joint measuring unit 300 may be a rotation angle of the knee joint on the sagittal plane of the wearer.

The bending angle measured by the encoder 330 worn on the knee joint of the wearer may also be transmitted to the controller 100 described above, and the controller 100 may determine the bending angle as the rotation angle of the knee joint.

On the other hand, the knee joint measuring unit 300 may be provided with an inertial measurement unit 330. The inertial measurement unit 330 provided in the knee joint measuring unit 300 may measure a rotation angle and / or a position value of the knee joint, and for this purpose, a 3-axis accelerometer and a 3-axis gyroscope And a magnetometer.

The reference axis of the original Euler angle derived from the inertial measurement unit 330 mounted on the knee joint measurement unit 300 is, as shown in FIG. 3, the position of the inertial measurement unit 330 of the knee joint measurement unit 300. Is set to the origin, and the longitudinal direction of the lower leg of the wearer is perpendicular to both the x-axis, the x-axis, and perpendicular to the wearer's sagittal plane, perpendicular to both the x-axis and the y-axis. The axis may be a reference axis set as a z axis.

The inertial measurement unit 330 mounted on the knee joint measurement unit 300 has a similar configuration except that the origin is different from that of the inertial measurement unit 230 mounted on the hip joint measurement unit 200, and thus is no longer overlapped. Description is omitted.

4 (a) and 4 (b) illustrate the ankle joint measuring unit 400 of the wearable lower body motion information collecting apparatus 1000 according to the present invention, with reference to the ankle joint measuring unit 400. Explain about.

The ankle joint measuring unit 400 of the wearable lower body motion information collecting device 1000 of the present invention measures the movement of the ankle joint of the wearer, and for this, the wearing unit 410, the encoder 420, and the inertial measurement unit 430. ), And may further include a plantar pressure sensor 440.

In detail, the wearing portion 410 to be worn on the ankle joint may be provided to surround the wearer's ankle joint, and in detail, the ankle joint portion may be bent on the ankle joint so as to be bent based on the ankle joint. A hinge is disposed, and the link member may be mounted and bent on the hinge.

The wearing part 410 may be configured to surround the wearer's ankle, the sole, and the foot, respectively, and the wearing part 410 surrounding the sole of the wearer is applied to the sole that can be used to analyze the walking state of the wearer. Ground reaction force measuring sensor 440 may be mounted to measure ground reaction force or plantar pressure. The ground reaction force measuring sensor 440 may be provided at the front and the rear of the foot, respectively, to identify a walking cycle such as early, middle, and late stances.

The encoder 420 to be worn on the ankle joint may be provided to measure the rotation angle of the ankle joint of the wearer, and bend angle of the link member mounted to the hinge is mounted on the hinge region of the ankle joint wearing portion 410. By measuring the rotation angle of the ankle joint of the wearer can be measured.

Here, it may be assumed that the bending angle of the ankle joint is also the rotation angle on the sagittal surface of the wearer's body.

Here, in order to fit the reference axis of the sagittal plane in the same way as the above-described hip and knee joint, as shown in Figure 4, the axis through the wearer's ankle joint and perpendicular to the sagittal plane can be set to the y-axis.

Accordingly, the bending angle measured by the encoder 420 of the ankle joint measuring unit 400 may be a rotation angle of the ankle joint on the sagittal plane of the wearer.

The encoder 420 worn on the wearer's ankle joint may be transmitted to the measured bending angle as well as the controller 100 described above, and the controller 100 may receive the bending angle to determine the rotation angle of the ankle joint. .

On the other hand, the ankle joint measuring unit 400 may be provided with an inertial measurement unit 430. The inertial measurement unit 430 provided in the ankle joint measuring unit 400 may measure a rotation angle and / or a position value of the ankle joint, and for this purpose, a 3-axis accelerometer and a 3-axis gyro sensor ( A gyroscope and a magnetometer may be provided.

The reference axis of the original Euler angle derived from the inertial measurement unit 430 mounted on the ankle joint measurement unit 400 is, as shown in FIG. 4, the inertial measurement unit 430 of the ankle joint measurement unit 400. Set the position of as the origin, the direction in which the instep of the wearer's foot extends on the x-axis, perpendicular to the x-axis and penetrating the origin but perpendicular to the wearer's sagittal plane, both the y-axis, the x-axis and the y-axis It may be a reference axis set as an z-axis perpendicular to the axis.

The inertial measurement unit 430 mounted on the ankle joint measurement unit 400 has a point of origin different from the inertial measurement unit 230 or 330 mounted on the hip joint measurement unit 200 or the knee joint measurement unit 300. Except for the overlapping description, since the configuration is almost the same.

The ground reaction force measuring sensor 440 may be mounted on the sole region of the wearer so as to measure the ground reaction force or plantar pressure applied to the sole, and the controller 100 refers to the measured value of the ground reaction force measuring sensor 440. It can be used to analyze the walking cycle or lower body motion of the wearer.

For example, when the ground reaction force is not measured by the ground reaction measurement sensor 440, the foot equipped with the ground reaction force measurement sensor 440 may be determined as an angle and used for motion analysis, and the predetermined ground reaction force is measured. If so, it can be used for motion analysis by judging by standing.

In addition, in the stator phase, the difference between the ground reaction force in the front region of the foot of the wearer and the ground reaction force in the rear region may also be used in motion analysis by determining whether it is the initial stage, the middle stage or the late stage.

5 is a view illustrating a control unit 100 and a configuration connected thereto of the wearable lower body motion information collecting apparatus 1000 according to the present invention, and the control unit 100 will be described with reference to the figure.

The control unit 100 of the wearable lower body motion information collecting apparatus 1000 according to the present invention may be provided in the main body as described above, and the control unit 100 may include the hip joint measuring unit 200 and the knee joint measuring unit 300. And the rotation angles of the joints measured by the encoders 220, 320, and 420 of the ankle joint measurement unit 400, and determine the rotation angles of the joints derived by the received encoders 220, 320, and 420. You can decide.

The controller 100 may transmit the derived rotation angle to the external analysis device E using a communication function provided in the main body, and the transmitted values are encoders 220, 320, provided in each joint region. Compensation in which the rotation angle received from 420, the original Euler angle received and converted through the inertial measurement device 230, 330, and 430 described above, or the rotation angle and original Euler angle received by the encoder are converted by predetermined logic. Euler angle may be.

The control unit 100 may determine the position and posture of each joint in the wearer's space based on the length of the wearer's thigh and the length of the lower thigh, and the control unit 100 provides a measurement value and the determination is performed by an external analyzer ( May be performed by E).

FIG. 6 illustrates a conceptual diagram of a process of determining an accurate Euler rotational angle in space of a corresponding joint by converting and compensating measured values provided from an encoder and an inertial measurement apparatus provided in at least one joint measuring unit.

The joint measuring unit may be one of the above-described hip joint measuring unit 200, knee joint measuring unit 300, and ankle joint measuring unit 400, and in each joint in the same manner in the exact three-dimensional space of the joint in space. The angle of rotation can be measured.

Referring to this, as described above, each joint measuring unit may collect the rotation angle θ _Enc measured by the encoder and the quaternary number q0, q1, q2 and q3 measured by the inertial measurement apparatus.

The control unit 100 converts the number of employees q0, q1, q2, and q3 provided by the inertial measurement apparatus using (Equation 1) to (Equation 3) (Rotation matrix calculation) to form an original Euler angle. The rotation angle rolling angle ф on the x axis, the rotation angle pitch angle on the y axis, and the rotation angle yaw angle ψ on the z axis can be converted.

By the way, the original Euler angles (rolling angle (ф), pitch angle (θ) and yaw angle (ψ)) obtained here are based on the inertial measurement unit 330, and the position of the inertial measurement unit and the position of the joint The error may be amplified when the joint axis is misaligned during operation due to an error or a physical characteristic, or when the joint axis is determined as the spatial rotation angle of each joint by the original Euler angle (ф, θ, ψ). .

Therefore, a process of compensating is performed based on the pitch angle θ of the original Euler angle and the rotation angle θ _Enc measured by the encoder, wherein the compensation is converted from the quaternary numbers q0, q1, q2, and q3. By comparing only the rotation angle pitch angle θ based on the y-axis, the error angle θ _err can be calculated by Equation 4 below. Compensation of the entire compensation (rolling angle (ф), pitch angle (θ) and yaw angle (ψ)) to determine the compensated compensation Euler angle, and the compensation Euler angle as a rotation angle in the form of the spatial Euler angle of each joint You can decide.

.....(식4)

..... (Equation 4)

The process of calculating and compensating such an error assumes that the propensity of the error of the pitch angle θ of the original Euler angle is reflected in the rolling angle and the yawing angle of the original Euler angle.

Therefore, a compensation matrix can be calculated to reflect the original Euler angle (rolling angle ф, pitch angle θ, and yaw angle ψ) through the pitch angle error.

Here, in order to extract only the pitch angle θ from the values of the original Euler angles (rolling angle ф, pitch angle θ, and yaw angle ψ) for calculating the aforementioned error, the original matrix is rolled by the Roll and Yaw angles. A rotation matrix that rotates inversely can be computed, and a compensation matrix is calculated by inversely calculating the error value calculated in the aforementioned error comaprison (error comparison), and this compensation matrix [R _θ ] is given by the following equation (5). .

.....(식5)

..... (Eq. 5)

When the compensation matrix is determined, the controller 100 multiplies the original Euler angles (rolling angle ф, pitch angle θ and yaw angle ψ) by the matrix as shown in Equations 6 and 7. The compensation Euler angles (rolling angle φ, pitch angle θ and yaw angle ψ) compensated by the encoder 320 measurement value can be derived as the rotation angle of the knee joint.

Original Euler angles (ф, θ, ψ) X Compensation matrix [R _θ ] = Compensated Euler angles (ф ', θ', ψ ') ... (Equation 6)

.....(식7)

... (Eq. 7)

Therefore, through this compensation process, it is possible to determine the exact angle of rotation of the Euler angle shape in the space of each joint.

When the compensation Euler angle is determined as the spatial rotation angle of each joint, the error generated by the displacement of the hinge axis in which the encoder rotation angle is measured in space during displacement of the joint is measured and derived through the inertial measurement unit. Comparing with the Euler angle, it can be seen that.

Figure 7 shows an example of the movement of the lower body of the wearer, Figure 8 shows an example of a change in the rotation angle of each joint of the wearer measured in the wearable lower body motion information collecting device 1000 of the present invention accordingly .

Here, the red line shows the pitch angle of the angle of each joint of the wearer through the motion capture of the image measuring device (Vicon), the black graph is the inertia of the wearable lower body motion information collecting device 1000 according to the present invention The pitch angle of the original Euler angle measured by the measuring device is shown, and the blue graph compensates the original Euler angle measured by the inertial measuring device of the wearable lower body motion information collecting device 1000 according to the present invention with the encoder measuring angle. One compensation pitch angle is shown.

Referring to this, the wearer may perform walking without restriction of a place while wearing the wearable lower body motion information collecting apparatus 1000 of the present invention. At this time, as shown in Figure 7, the rotation angle (θ _Trunk , θ _Hip , θ _Knee , θ _Ankle ) with respect to each joint can be measured, respectively, the measured rotation angle is accurate by the above-described compensation operation Can be converted to a rotation angle.

In addition, since the position of each joint in space can be determined based on the rotation angle of the joint according to the length of each thigh and the length of the thigh of the wearer, the Euler angle of each joint provided in the motion information analyzer according to the present invention. The rotation angle of the shape can be used as a basic data for analyzing the motion intention based on the wearer's posture based on the length of the wearer's thigh and lower leg.

Here, if the rotation angles (θ _Trunk , θ _Hip , θ _Knee , θ _Ankle ) change according to the wearer's gait extracted based on the rotation angle of the joint collected through the wearable lower body motion information collecting device according to the present invention. Accordingly, as shown in FIG. 8, the graph shown in the control unit 100 or the external analysis device E of the wearable lower body motion information collecting apparatus 1000 is changed, and the changed graph, that is, the change in the rotation angle is measured. And by analyzing the wearer's lower body motion and walking characteristics can be analyzed.

The original Euler angle (pitch angle) measured and converted by the inertial measurement device constituting the wearable lower body motion information collecting device 1000 according to the present invention under the premise that the motion information measured by the image photographing apparatus in FIG. 8 is the most accurate. Compared with the rotation angle (pitch angle) collected by the image capturing apparatus, it can be confirmed that some errors exist but there is considerable matching or tracking.

However, as shown in FIG. 8, the compensating Euler angle (pitch angle) of compensating the original Euler angle measured and converted by the encoder value measured in the inertial measurement device constituting the wearable lower body motion information collecting apparatus 1000 is It can be seen that the rotation angle and error of the joint obtained by the image photographing device are smaller than the original Euler angle.

Therefore, by wearing and wearing the wearable lower body motion information collecting device 1000 according to the present invention to measure and analyze the motion of the wearer to capture the motion capture of the image measuring device using a marker and a plurality of cameras are expensive, severe space constraints and measurement limitations It is easy and simple to measure and analyze the wearer's movement without using.

In addition, in the present invention, after the inertial measurement unit measures the spatial value with the quaternion, the control unit converts to the Euler angle, thereby preventing the gimbal lock phenomenon, and using the encoder value for the Euler angle derived from the inertial measurement unit. Wearable lower body motion to accurately measure the physical characteristics and intention of the wearer by using the position value corrected by the encoder value by correcting it with the encoder's rotation reference axis value. Information collection devices can be used.

In addition, it can be attached to a suit worn on the body can perform motion analysis in a variety of environments without the constraints of space, and can measure the ground reaction during any lower limb movement through the ground force sensor in the form of shoes, Wearable lower body motion information collection device that can grasp the various intentions of the wearer, such as standing, going up and down stairs, falls.

The wearable lower body motion information collecting device according to the present invention has been described above. However, a person having ordinary knowledge in the technical field to which the embodiment belongs may be embodied in other specific forms without changing the present invention to technical spirit or essential features. You will understand that there is. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive.

100: control unit
200: hip joint measurement unit
300: knee joint measurement unit
400: ankle joint measurement unit

Claims (7)

A hip measurement unit which is worn on the hip joint area of the wearer and has an encoder for detecting rotation of the hip joint of the wearer;
A knee joint measurement unit which is worn in the knee joint region of the wearer and has an encoder for detecting a rotation angle of the knee joint of the wearer; And,
Wearable lower body motion information including an encoder for the hip joint measurement unit and a control unit for receiving the rotation angle of the joint measured by the encoder of the knee joint measurement unit, and determining the hip joint rotation angle and the knee joint rotation angle derived by the received encoder measurement value. Collector. The method of claim 1,
The wearable lower body motion information collection device, characterized in that the wearer's ankle joint region, further comprising an ankle joint measuring unit having an encoder for detecting the rotation angle of the wearer's ankle joint. The method of claim 1,
The control unit is mounted around the waist of the wearer, wearable lower body motion information collection device, characterized in that provided in the main body having a power supply and an external analysis device and the communication function. The method of claim 2,
The encoder provided in each joint is mounted to the hinge region of the bendable link member constituting the wearing portion worn on each joint, wherein each encoder measures the bending angle of the link member connected by the hinge. Wearable lower body motion information collecting device. The method of claim 2,
At least one joint measuring unit of each joint measuring unit further includes an inertial measuring unit including a 3-axis accelerometer, a 3-axis gyroscope, and a magnetometer, wherein the inertia is measured by the controller. Wearing lower body motion information collection device, characterized in that the rotation angle of the joint derived by the value measured through the joint measuring unit with a measuring device is Euler angle. The method of claim 5,
The control unit or an external analysis device that can communicate with the control unit uses the original Euler angles (rolling angle ф), using the four _numbers (Quaternion, q ₀ , q ₁ , q ₂ , q ₃ ) measured by the inertial measurement unit. After calculating the pitch angle θ and yaw angle ψ, the pitch angle θ is extracted and the pitch angle θ and the measured angle θ _enc of the encoder of the joint provided with the inertial measurement apparatus are calculated. Compensation of each joint by deriving the compensation matrix R _θ based on the error angle θ _err and compensating the original Euler angle (rolling angle ф, pitch angle θ and yaw angle ψ). Wearing lower body motion information collection device, characterized in that to derive the Euler angle (rolling angle (ф), pitch angle (θ) and yaw angle (ψ)) as the rotation angle of the joint. The method of claim 1,
The control unit or an external analysis device that can communicate with the control unit wearable lower body motion information collection device, characterized in that for determining the position and posture of each joint in the wearer's space based on the length of the wearer's thigh and the length of the lower thigh.

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