KR102510984B1 - Method and apparatus for setting assistant torque - Google Patents

Abstract

An assisting force setting method and apparatus are disclosed. An assistive force setting apparatus according to an embodiment calculates an evaluation value of at least one index based on user gait data, sets a stable assist force based on the evaluation value, and determines a user's gait motion based on the gait data. It is possible to set the basic assisting force according to the above, and set the final assisting force based on the stability assisting force and the basic assisting force.

Description

Auxiliary force setting method and device {METHOD AND APPARATUS FOR SETTING ASSISTANT TORQUE}

The following embodiments relate to a method and apparatus for setting an assisting force.

Recently, as the aging society intensifies, the number of people who complain of pain and discomfort due to joint problems is increasing, and interest in walking aids that can facilitate walking of the elderly or patients with joint discomfort is increasing. In addition, walking assistance devices for strengthening the muscular strength of the human body for purposes such as military use are being developed.

For example, the walking assistance device includes a body frame mounted on the user's torso, a pelvic frame coupled to the lower side of the body frame to surround the user's pelvis, a thigh frame mounted on the user's thighs, calves, and feet, and calves. It consists of a frame and a foot frame. The pelvis frame and the femoral frame are rotatably connected by the hip joint, the femoral frame and the calf frame are rotatably connected by the knee joint, and the calf frame and the foot frame are rotatably connected by the ankle joint.

The prior invention of European Patent Publication No. EP 1932567 relates to an exercise induction device, and discloses a method for inducing a user's exercise with an appropriate rhythm according to the exercise rhythm after the change even when the user's exercise rhythm suddenly changes. .

An assisting force setting device according to an exemplary embodiment includes a gait data receiving unit configured to receive gait data of a user; a stability assist force setting unit configured to set a stability assist force using an evaluation value of at least one index based on the gait data; a basic assisting force setting unit configured to set a basic assisting force according to the user's gait motion based on the gait data; and a final assisting force setting unit configured to set a final assisting force based on the stabilizing assisting force and the basic assisting force.

The stability assist force setting unit may include an index evaluator calculating an evaluation value of at least one index based on the gait data; a weight calculator configured to calculate a weight for the at least one index based on a difference between the evaluation value and a threshold value corresponding to the at least one index; and a stability assisting force calculator configured to calculate the stabilizing assisting force by applying the weight to the initial stabilizing assisting force corresponding to the at least one index.

The at least one index may include gait symmetry indicating the degree of symmetry of both legs of the user, a stride length and a stride width of the user, and a distance between the user's feet and the ground. It may include at least one of a foot clearance representing an interval, a landing speed representing a speed at which the user's foot touches the ground, or a walk ratio.

The index evaluator may classify the gait data based on a stride, and calculate an evaluation value of the at least one index based on the gait data classified based on the stride.

The index evaluation unit may determine whether the user's gait is stable based on the at least one index by comparing the evaluation value with the threshold value.

The index evaluation unit may estimate a similarity between a trajectory of a left hip joint angle and a trajectory of a right hip joint angle of the user among the gait data, and determine the similarity as an evaluation value of the gait symmetry.

The index evaluator may estimate a similarity between the trajectory of the left hip joint angle and the trajectory of the right hip joint angle by using dynamic time warping (DTW).

The index evaluator estimates an average stride length by calculating an average of a left hip joint angular range and an average of a right hip joint angular range among the gait data for a plurality of strides, and calculates the average stride length for the stride length It can be determined by the evaluation value.

The index evaluation unit extracts, for a plurality of strides, the maximum flexion angle of the left hip joint and the maximum flexion angle of the right hip joint from the gait data, and the maximum flexion angle of the left hip joint and the right hip The maximum bending angle of the joint may be determined as an evaluation value for the foot clearance.

The weight calculation unit may calculate the weight by normalizing a difference between the evaluation value and the threshold value.

The weight calculation unit may set a weight to zero for an index determined by the index evaluation unit to be stable in walking of the user.

The stability assist force calculation unit may set the initial stability assist force based on the gait data.

The stabilization assist force calculation unit may set the initial stabilization assist force for the gait symmetry based on a difference between a trajectory of a left hip joint angle and a trajectory of a right hip joint angle among the gait data.

The stabilizing force calculation unit extracts a crossing time point at which the user's left leg and right leg intersect using the trajectory of the left hip joint angle and the trajectory of the right hip joint angle among the gait data, and calculates a predetermined value from the crossing time point. A peak torque during time may be set as the initial stabilizing assist force for the stride length.

The stabilizing force calculation unit extracts a point in time when the swinging leg of the user approaches the ground using the trajectory of the left hip joint angle and the trajectory of the right hip joint angle among the gait data, and determines whether the swinging leg touches the ground. A peak torque for a predetermined time from the point of approaching may be set as the initial stabilizing assist force for the foot clearance.

The apparatus for setting an assisting force according to an exemplary embodiment further includes a gait motion recognizing unit configured to recognize a gait motion of the user based on the gait data, and the basic assisting force setting unit determines the gait motion of the user in the gait motion recognizing unit. When it is recognized that the basic assisting force is not performed, the basic assisting force may be set to zero.

The basic assisting force setting unit estimates the periodicity of the user's gait motion by applying the gait data to an adaptive oscillator (AO), and converts the assisting force corresponding to the periodicity of the gait motion into the basic assisting force. can be set

The basic assistance force setting unit models the gait motion of the user in a plurality of states, applies the gait data to a finite state machine (FSM), and then the gait of the user among the plurality of modeled gait states. A walking state corresponding to the motion may be recognized, and an assisting force according to the recognized walking state may be set as the basic assisting force.

The final assisting force setting unit may set the final assisting force by adding the stability assisting force and the basic assisting force.

The final assisting force setting unit may set a larger absolute value of the stabilizing assisting force and the basic assisting force as the final assisting force.

An assistive force setting apparatus according to an exemplary embodiment includes an index estimator configured to calculate an evaluation value of at least one index representing a user's gait stability based on gait data of the user; a weight calculator configured to calculate a weight for the at least one index based on a difference between the evaluation value and a threshold value corresponding to the at least one index; and an assisting force setting unit configured to set the stabilizing assisting force by applying the weight to the initial stabilizing assisting force corresponding to the at least one index.

The stability assist force setting unit may set the initial stability assist force based on the gait data.

The assisting force setting device according to an exemplary embodiment further includes a basic assisting force setting unit configured to set a basic assisting force according to the user's gait motion based on the gait data, wherein the assisting force setting unit includes the basic assisting force and the basic assisting force. The final assist force can be set based on the stability assist force.

A walking assistance device according to an embodiment includes a gait data receiver configured to receive gait data of a user; a stability assist force setting unit that calculates an evaluation value of at least one index based on the gait data and sets a stability assist force based on the evaluation value; a basic assisting force setting unit configured to set a basic assisting force according to the user's gait motion based on the gait data; a final assisting force setting unit configured to set a final assisting force based on the stabilizing assisting force and the basic assisting force; and a driving controller controlling driving of the walking assistance device based on the final assisting force.

According to an exemplary embodiment, a method of setting an assistance force includes receiving gait data of a user; calculating an evaluation value of at least one index based on the gait data, and setting a stability assist force based on the evaluation value; setting a basic assisting force according to the user's gait motion based on the gait data; and setting a final assisting force based on the stabilizing assisting force and the basic assisting force.

An assistive power setting method according to an exemplary embodiment includes calculating an evaluation value of at least one index indicating a user's gait stability based on gait data of the user; calculating a weight for the at least one index based on a difference between the evaluation value and a threshold value corresponding to the at least one index; and setting a stabilization assist force by applying the weight to an initial stabilization assist force corresponding to the at least one index.

A walking assistance method according to an embodiment includes receiving walking data of a user; calculating an evaluation value of at least one index based on the gait data, and setting a stability assist force based on the evaluation value; setting a basic assisting force according to the user's gait motion based on the gait data; setting a final assisting force based on the stabilizing assisting force and the basic assisting force; and controlling driving of a walking assistance device based on the final assisting force.

.

1 is a diagram for explaining a walking assistance device according to an exemplary embodiment.
2 is a block diagram illustrating an assisting force setting device according to an exemplary embodiment.
3 is a block diagram illustrating an assisting force setting device according to another exemplary embodiment.
4 is a block diagram illustrating an assisting force setting device according to another exemplary embodiment.
5 is an operation flowchart illustrating setting of a final assisting force according to an exemplary embodiment.
6 is a diagram for explaining setting of a basic assisting force according to an exemplary embodiment.
7 is a diagram for explaining calculation of an evaluation value for gait symmetry according to an exemplary embodiment.
8 is a diagram for explaining setting of an initial stability assist force for gait symmetry according to an exemplary embodiment.
9 is a diagram for explaining setting of an initial stabilization assist force with respect to a stride length according to an exemplary embodiment.
10 is a diagram for explaining setting of an initial stabilizing assist force for foot clearance according to an embodiment.
11 is a diagram for explaining setting of an assisting force according to an exemplary embodiment.
12 is a diagram for explaining an interface for providing an assisting force according to an exemplary embodiment.
13 is a block diagram illustrating a walking assistance device according to an exemplary embodiment.
14 is a flowchart illustrating a method of setting an assisting force according to an exemplary embodiment.
15 is a flowchart illustrating a method of setting an assisting force according to another exemplary embodiment.
16 is a method flowchart illustrating a walking assistance method according to an exemplary embodiment.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Like reference numerals in each figure indicate like elements.

Various changes may be made to the embodiments described below. The embodiments described below are not intended to be limiting on the embodiments, and should be understood to include all modifications, equivalents or substitutes thereto.

Terms used in the examples are used only to describe specific examples, and are not intended to limit the examples. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, terms such as "include" or "have" are intended to designate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, but one or more other features It should be understood that the presence or addition of numbers, steps, operations, components, parts, or combinations thereof is not precluded.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which the embodiment belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and unless explicitly defined in the present application, they should not be interpreted in an ideal or excessively formal meaning. don't

In addition, in the description with reference to the accompanying drawings, the same reference numerals are given to the same components regardless of reference numerals, and overlapping descriptions thereof will be omitted. In describing the embodiment, if it is determined that a detailed description of a related known technology may unnecessarily obscure the gist of the embodiment, the detailed description will be omitted.

1 is a diagram for explaining a walking assistance device according to an exemplary embodiment.

Referring to FIG. 1 , a walking assistance device 100 may be mounted on a user to help the user walk. The walking assistance device 100 includes a driver 110 , a sensor unit 120 , an inertial measurement unit (IMU) sensor 130 and a controller 140 . Although a hip-type walking assistance device is shown in FIG. 1 , it is not limited thereto, and may be applied to both a type supporting the entire lower extremity and a type supporting a part of the lower extremity. In addition, it can be applied to a form of supporting a part of the lower extremity, a form of supporting up to the knee, a form of supporting up to the ankle, and a form of supporting the whole body.

The driver 110 drives both hip joints of the user and may be located on the right and left hips of the user.

The sensor unit 120 measures both hip joint angle information of the user during walking. Both hip joint angle information sensed by the sensor unit 120 may include at least one of the angle of both hip joints, the difference between the angles of both hip joints, and the movement directions of both hip joints. In one embodiment, the sensor unit 120 may be located within the driver 110 .

In another embodiment, the sensor unit 120 may include a potentiometer. The potentiometer may sense at least one of R-axis and L-axis joint angles or R-axis and L-axis joint angular velocities according to the user's walking motion.

The IMU sensor 130 measures acceleration information and posture information when a user walks. For example, the IMU sensor 130 may sense at least one of X-axis, Y-axis, and Z-axis acceleration or X-axis, Y-axis, and Z-axis angular velocity according to the user's walking motion. The walking assistance device 100 may detect a landing point of the user's foot based on the acceleration information measured by the IMU sensor 130 . However, when the sensor unit 120 includes a sensor capable of detecting a landing point of the foot (for example, a pressure sensor or a force sensor), the walking assistance device 100 may The landing time of the user's foot may be detected using a sensor capable of detecting the landing time.

In addition, the walking assistance device 100 includes, in addition to the sensor unit 120 and the IMU sensor 130 described above, other sensors capable of sensing a change in the amount of exercise or biosignal of the user according to the walking motion (eg, electromyography). A sensor (ElectroMyoGram sensor: EMG sensor) may be included.

The controller 140 controls the actuator 110 so that the actuator 110 outputs auxiliary force (or auxiliary torque) for assisting the user's walking. For example, in the hip-type walking assistance device 110, there may be two actuators 110, and the controller 140 controls the actuator 110 to output an assisting force corresponding to the actuator 110 ( 110) may output a control signal. Based on the control signal output from the controller 140, the actuator 110 may output an auxiliary force. At this time, the auxiliary force may be set by the outside, or the controller 140 may set the auxiliary force.

2 is a block diagram illustrating an assisting force setting device according to an exemplary embodiment.

Referring to FIG. 2 , the assisting force setting device 200 may be a separate device physically independent of the walking assistance device or may be implemented as a logical model within the walking assistance device. Hereinafter, a basic unit of walking may be a step or a stride. A step can be divided into one heel strike. Here, the heel strike represents a state in which the sole of the user's foot touches the ground. Also, a stride may consist of two steps.

The assisting force setting device 200 includes a gait data receiving unit 210 , a stability assisting force setting unit 220 , a basic assisting force setting unit and a final assisting force setting unit 240 .

The gait data receiving unit 210 receives gait data obtained by sensing a change in the amount of exercise of the user according to a gait motion from a sensor. The gait data receiving unit 210 may receive gait data from a sensor that measures a user's gait motion or may receive gait data from an external device. For example, the gait data receiving unit 210 may receive information on both hip joints of the user (eg, R-axis, L-axis joint angle or R-axis, L-axis joint angular velocity) from the potentiometer, and the IMU sensor Information (X-axis, Y-axis, Z-axis acceleration or X-axis, Y-axis, and Z-axis angular velocity) about the motion directions of both hip joints may be received from the . Also, the gait data receiving unit 210 may receive gait data from a plurality of IMU sensors or a plurality of potentiometers. In one embodiment, the gait data receiving unit 210 is not limited to an IMU sensor, a potentiometer, or an EMG sensor, and may receive gait data from any sensor capable of sensing a change in a user's exercise amount according to a gait motion. For example, the gait data receiving unit 210 may receive EMG data indicating a change in EMG of the user according to walking from an EMG sensor. Also, the gait data receiver 210 may receive pressure data or force data according to the user's gait from a pressure sensor or a force sensor.

Also, the gait data receiving unit 210 may receive gait data of the user from an external device including a sensor for measuring the gait motion of the user through a communication interface. Hereinafter, communication interfaces include Wireless LAN (WLAN), Wireless Fidelity (WiFi) Direct, Digital Living Network Alliance (DLNA), Wireless broadband (Wibro), World Interoperability for Microwave Access (Wimax), High Speed Downlink Packet Access (HSDPA) Bluetooth, Radio Frequency Identification (RFID), Infrared Data Association (IrDA), UWB (Ultra Wideband), ZigBee, NFC (Near Field Communication), etc. can In addition, the communication interface may indicate any interface (eg, a wired interface) capable of performing communication with an external device.

The stability assist force setting unit 220 may set the stability assist force using an evaluation value of at least one index based on gait data. The stability assist force setting unit 220 includes an index evaluation unit, a weight calculation unit, and a stability assist force calculation unit.

The index evaluation unit calculates an evaluation value of at least one index representing the user's gait stability based on the user's gait data. Here, the at least one index is at least one of gait symmetry, stride length, stride width, foot clearance, landing speed, or walk ratio. may contain one.

In one embodiment, the index evaluator may classify the gait data based on the stride and calculate an evaluation value of at least one index based on the classified gait data. For example, the index evaluator may classify the gait data based on the stride using the Z-axis acceleration obtained from the IMU sensor. As another example, the index evaluator receives a sensing value when the user's foot contacts the ground from a pressure sensor or a force sensor attached to the user's foot, and classifies the gait data based on the stride using the received sensing value. can However, the index evaluation unit is not limited thereto, and may use gait data classified based on steps or gait data classified based on other units.

Gait symmetry represents the degree to which both legs of the user are symmetrical. When the user walks, the user's legs swing or stand, but if the load on the user's muscles becomes unbalanced, one of the user's legs becomes weak and the left leg and right leg become unbalanced. may not be maintained. In order to maintain balance between the left leg and the right leg, the index evaluation unit may include gait symmetry in the index.

The stride length (or stride length) represents the vertical length of one stride in the user's walking motion. For example, the stride length may represent a length from when the left/right leg swings based on the fixed left/right leg until the left/right leg is fixed again. When the user's muscle strength is reduced, the stride length is reduced, and accordingly, the user is unable to sufficiently utilize the dynamic energy of the body for walking, which causes a burden on the muscles, which may increase the decrease in muscle strength. To prevent this vicious cycle, the index evaluator may include the stride length in the index.

The stride width may represent the left and right widths of one stride in the user's gait motion. When the user's muscle strength decreases, the user may try to take a wider width of both legs in order to maintain balance on their own. In this case, a large load is applied to the aduction/abduction muscles of the hip joint for the left and right balance of the body, but if the aduction/abduction muscles of the hip joint do not bear the load, the user may fall. . To prevent this risk, the index evaluation unit may include the stride width in the index.

The foot clearance indicates the distance between the user's foot and the ground (eg, the maximum height between the foot and the ground in one stride, and the maximum height between the tip of the user's foot and the ground). A normal user can sufficiently bend the ankle of the swinging leg while walking. On the other hand, when the muscle strength of the ankle muscles is weakened, the user's feet do not sufficiently bend the swinging leg during walking, and thus the user's feet collide with obstacles on the ground, resulting in a fall. To prevent this risk, the index evaluation unit may include foot clearance in the index.

The landing speed represents the speed at which the user's foot touches the ground. When walking, a normal user may decelerate the swinging leg at the point of landing on the ground, thereby increasing the leg's contact force with the ground and absorbing the impact of the leg. On the other hand, a user with reduced muscle strength cannot sufficiently decelerate the speed at the point when the leg lands on the ground, and as a result, the user may slip and fall. To prevent this risk, the index evaluator may include the landing speed in the index.

Also, the gait ratio may be defined as a ratio of a stride length and a cadence. Here, the cadence may indicate the number of strides relative to a predetermined reference time. The gait ratio may be used as an index indicating how efficiently a user walks.

In addition, the index evaluator may preset a threshold value for determining whether the user's gait is stable based on each index. The index evaluator may compare an evaluation value and a threshold value for each index to determine whether the user's gait is stable based on each index.

In an embodiment, the index evaluator may estimate a similarity between a trajectory of a left hip joint angle and a trajectory of a right hip joint angle of the user among gait data, and determine the estimated similarity as an evaluation value of gait symmetry. At this time, the trajectory of the left hip joint angle and the trajectory of the right hip joint angle may be one step apart.

The index evaluation unit may determine an evaluation value of gait symmetry using Equation 1 below.

[Equation 1]

은 n번째 스트라이드에서의 보행 대칭성의 평가값을 나타내고, DTW는 다이나믹 타임 와핑(Dynamic Time Warping: DTW) 기법을 나타내고,

은 n번째 스트라이드에서의 왼쪽 힙 관절 각도의 궤적을 나타내고,

은 n번째 스트라이드에서의 오른쪽 힙 관절 각도의 궤적을 나타내고,

은 보행 대칭성에 대응하는 임계값을 나타낼 수 있다.here,

denotes an evaluation value of gait symmetry in the n-th stride, DTW denotes a dynamic time warping (DTW) technique,

Represents the trajectory of the left hip joint angle at the nth stride,

Represents the trajectory of the right hip joint angle at the nth stride,

may represent a threshold value corresponding to gait symmetry.

및

가 각각 측정되는 시간들 간에는 한 번의 스텝에 걸리는 시간만큼 차이가 날 수 있다.Because the left leg and right leg swing alternately,

and

There may be a difference by the time taken for one step between the times at which is measured.

가 임계값

이하인 경우, 인덱스 평가부는 n번째 스트라이드에서, 보행 대칭성을 기준으로 사용자의 보행이 안정하다고 판단할 수 있고, 평가값

가 임계값

보다 큰 경우, 인덱스 평가부는 n번째 스트라이드에서, 보행 대칭성을 기준으로 사용자의 보행이 불안정하다고 판단할 수 있다.The index evaluator may estimate a similarity between the trajectory of the left hip joint angle in the left n-th stride and the trajectory of the right n-th right hip joint angle by using dynamic time warping. The index evaluator may determine the estimated similarity as an evaluation value of gait symmetry in the n-th stride. In addition, the index evaluation unit evaluates the value

is the threshold

In the case of the following, the index evaluation unit may determine that the user's gait is stable based on the gait symmetry in the nth stride, and the evaluation value

is the threshold

If it is greater than the index evaluator, the index evaluator may determine that the user's gait is unstable based on gait symmetry in the n-th stride.

In one embodiment, the index evaluator may estimate the average stride length using the left hip joint angular range and the right hip joint angular range, and determine the average stride length as an evaluation value for the stride length. At this time, in order to increase accuracy, the index evaluator may calculate an average of the left hip joint angular range and an average of the right hip joint angular range during a plurality of strides, and estimate the calculated average as the average stride length. In another embodiment, the index evaluator may receive a sensing value when the user's foot contacts the ground from a pressure sensor or a force sensor mounted under the user's foot, and the index evaluator may use the received sensing value to determine an average stride value. length can be estimated.

The index evaluator may determine the evaluation value of the stride length using Equation 2 below.

[Equation 2]

는 왼쪽(오른쪽) 다리의 스트라이드 길이의 m번째 평가값을 나타내고,

은 n개의 스트라이드에서의 왼쪽(오른쪽) 힙 관절 각도 범위를 나타내고,

은 왼쪽(오른쪽) 다리의 스트라이드 길이에 대응하는 임계값을 나타낼 수 있다.here,

Represents the mth evaluation value of the stride length of the left (right) leg,

Represents the left (right) hip joint angular range in n strides,

may represent a threshold value corresponding to the stride length of the left (right) leg.

For example, when n is 100, the index evaluator may calculate an average of the left hip joint angular range and the right hip joint angular range in 100 strides. At this time, the index evaluation unit may estimate the range between the maximum and minimum values of the left hip joint angle as the left hip joint angle range, and the range between the maximum and minimum values of the right hip joint angle as the right hip joint angle range. can do.

이 임계값

이상인 경우, 인덱스 평가부는 스트라이드 길이를 기준으로 사용자의 보행이 안정하다고 판단할 수 있고, 평가값

이 임계값

보다 작은 경우, 인덱스 평가부는 스트라이드 길이를 기준으로 사용자의 보행이 불안정하다고 판단할 수 있다.Also, the evaluation value

this threshold

In the above case, the index evaluation unit may determine that the user's gait is stable based on the stride length, and the evaluation value

this threshold

If it is smaller than the index evaluator, the index evaluator may determine that the user's gait is unstable based on the stride length.

In one embodiment, the index evaluation unit extracts the maximum flexion angle of the left hip joint and the maximum flexion angle of the right hip joint from the gait data, and the maximum flexion angle of the left hip joint and the maximum flexion angle of the right hip joint It can be determined as an evaluation value for foot clearance. A normal user raises the toe end of the swinging leg using the ankle muscles while walking, whereas a pedestrian with weakened ankle muscle strength lifts the entire swinging leg using the hip joint muscles, so that the foot of the swinging leg is higher than normal users. The tip can be raised low. Accordingly, since the maximum flexion angle of the left hip joint and the maximum flexion angle of the right hip joint may indicate whether the muscle strength of the ankle muscles is normal, the index evaluation unit determines the maximum flexion angle of the left hip joint and the maximum flexion angle of the right hip joint can be determined as the evaluation value of the foot clearance.

The index evaluation unit may determine the evaluation value of the foot clearance using Equation 3 below.

[Equation 3]

는 왼쪽(오른쪽) 다리의 풋 클리어런스의 m번째 평가값을 나타내고,

은 n개의 스트라이드에서의 왼쪽(오른쪽) 다리의 굽힘 각도들을 나타내고,

는 왼쪽(오른쪽)다리의 굽힘 각도들 중 최대 굽힘 각도를 나타내고,

는 왼쪽(오른쪽) 다리의 풋 클리어런스에 대응하는 임계값을 나타낼 수 있다.here,

Represents the mth evaluation value of the foot clearance of the left (right) leg,

denotes the bending angles of the left (right) leg in n strides,

represents the maximum bending angle among the bending angles of the left (right) leg,

may represent a threshold value corresponding to the foot clearance of the left (right) leg.

For example, when n is 100, the index evaluator may extract the maximum bending angle of the left hip joint and the maximum bending angle of the right hip joint in 100 strides.

가 임계값

이상인 경우 인덱스 평가부는 풋 클리어런스를 기준으로 사용자의 보행이 안정하다고 판단할 수 있고, 평가값

가 임계값

보다 작은 경우 인덱스 평가부는 풋 클리어런스를 기준으로 사용자의 보행이 불안정하다고 판단할 수 있다.Also, the evaluation value

is the threshold

In the case of the above, the index evaluation unit may determine that the user's gait is stable based on the foot clearance, and the evaluation value

is the threshold

If it is smaller than the index evaluation unit, it may be determined that the user's gait is unstable based on the foot clearance.

The weight calculation unit may calculate a weight for at least one index based on a difference between an evaluation value of at least one index and a threshold value corresponding to the at least one index. The weight calculator may calculate a weight for at least one index by normalizing a difference between an evaluation value of at least one index and a threshold value corresponding to the at least one index, as shown in Equation 4 below.

[Equation 4]

는 왼쪽(오른쪽) 다리의 인덱스 i의 k번째 가중치를 나타내고,

는 왼쪽(오른쪽) 다리의 인덱스 i의 k번째 평가값을 나타내고,

는 왼쪽(오른쪽) 다리의 왼쪽(오른쪽) 다리의 k번째 임계값을 나타내고,

는 왼쪽(오른쪽) 다리의 인덱스 i의 정규화 값(normalizing value)을 나타낼 수 있다. 수학식 4에 따라, 인덱스의 평가값과 임계값의 차이가 클수록 가중치는 증가될 수 있다. 일 실시예에서, 가중치 연산부는 인덱스 평가부에서 사용자의 보행이 안정한 것으로 판단된 인덱스에 대한 가중치를 0으로 설정할 수 있다.here,

represents the k-th weight of index i of the left (right) leg,

represents the k-th evaluation value of the index i of the left (right) leg,

represents the k-th threshold of the left (right) leg of the left (right) leg,

may represent a normalizing value of the index i of the left (right) leg. According to Equation 4, the weight may be increased as the difference between the index evaluation value and the threshold value increases. In one embodiment, the weight calculation unit may set a weight to 0 for an index in which the user's gait is determined to be stable by the index evaluation unit.

The stability assist force calculation unit may calculate the stability assist force by applying a weight to the initial stability assist force corresponding to at least one index. Here, the stability assist force may represent a force provided by the walking assistance device so that the user can walk stably, and the initial stability assist force represents an initial value of the stability assist force, and may correspond to each of at least one index. there is. The initial stability assist force may be preset, or may be set by the stability assist force calculation unit based on gait data.

In an embodiment, the stability assist force calculation unit may set an initial stability assist force for gait symmetry based on a difference between a trajectory of a left hip joint angle and a trajectory of a right hip joint angle among gait data. The stability assist force calculation unit may set an initial stability assist force for gait symmetry according to Equations 5 to 7 below.

The timing at which the stride of the left leg and the stride of the right leg start may differ by the time required for one step. A difference between the left hip joint angle and the right hip joint angle may be calculated in consideration of the above time difference.

According to one aspect, a variable p may be used to account for the time difference. The variable p may be a variable that normalizes the stride trajectory. For example, the variable p may indicate a position of an entire stride trajectory in which the start of the stride is 0 and the end of the stride is 1.

Normalized stride time (NST) may be defined as a time when the stride is performed using the variable p.

In the same NST, the difference between the left hip joint angle and the right hip joint angle can be calculated using Equation 5 below.

[Equation 5]

θ _r (p) and θ _l (p) denote the right hip joint angle and the left hip joint angle at p NST, respectively.

The auxiliary force for improving the asymmetry may be calculated using Equations 6 and 7 below.

[Equation 6]

는 오른쪽 다리(왼쪽 다리)의 스트라이드 시작 시각이고,

는 1 번의 스트라이드의 시간을 나타낼 수 있다.

는

이후의 시각 t에 대해 오른쪽 다리(왼쪽 다리)의 스트라이드 궤적에서의 NST를 나타낼 수 있다.

is the stride start time of the right leg (left leg),

may represent the time of one stride.

Is

The NST at the stride trajectory of the right leg (left leg) may be represented at a later time t.

[Equation 7]

는 시각 t에 따라 왼쪽 다리에 제공하는 보행 대칭성에 대한 초기 안정 보조력을 나타내고,

는 시각 t에 따라 오른쪽 다리에 제공하는 보행 대칭성에 대한 초기 안정 보조력을 나타내고,

는 왼쪽 다리에 제공하는 보행 대칭성에 대한 초기 안정 보조력의 게인을 나타내고,

는 오른쪽 다리에 제공하는 보행 대칭성에 대한 초기 안정 보조력의 게인을 나타낸다.here,

Represents the initial stabilization assistance force for gait symmetry provided to the left leg according to time t,

Represents the initial stabilizing force for gait symmetry provided to the right leg according to time t,

Represents the gain of the initial stabilization assistance force for gait symmetry provided to the left leg,

represents the gain of the initial stabilization assistance force for gait symmetry provided to the right leg.

이후의 보조력이 결정될 수 있다.using Equation 7

The subsequent assisting force may be determined.

가 업데이트 될 수 있고, 보행 대칭성에 대한 안정 보조력이 반복적으로 계산될 수 있다.According to one aspect, the time when the next stride starts after the first stride ends, and

may be updated, and the stability assistance force for gait symmetry may be repeatedly calculated.

및

는 미리 설정될 수 있다. 수학식 7에 따라, 왼쪽 힙 관절 각도의 궤적 및 오른쪽 힙 관절 각도의 궤적의 차이가 발생하는 경우, 안정 보조력 연산부는 왼쪽 힙 관절의 각도 궤적과 오른쪽 힙 관절의 각도 궤적의 차이를 상쇄하도록 초기 안정 보조력을 설정할 수 있다.Also, gain

and

can be set in advance. According to Equation 7, when the difference between the trajectory of the left hip joint angle and the trajectory of the right hip joint angle occurs, the stabilization assist force calculation unit initially cancels the difference between the angular trajectory of the left hip joint and the angular trajectory of the right hip joint Stability assistance can be set.

In one embodiment, the stability assist force calculation unit extracts a crossing time point at which the user's left leg and right leg cross each other, and uses a peak torque for a predetermined time from the crossing time point as an initial stability assist force for the stride length. can be set Here, a predetermined time and peak torque may be set in advance. The stability assist force calculation unit may set the initial stability assist force for the stride length according to Equation 8 below.

[Equation 8]

는 시각 t에 따라 왼쪽 다리에 제공하는 스트라이드 길이에 대한 초기 안정 보조력을 나타내고,

는 시각 t에 따라 오른쪽 다리에 제공하는 스트라이드 길이에 대한 초기 안정 보조력을 나타내고,

은 시각 t에 따른 왼쪽 힙 관절의 각도의 궤적을 나타내고,

는 시각 t에 따른 오른쪽 힙 관절의 각도의 궤적을 나타내고,

은 왼쪽 다리의 스트라이드 길이의 평가값을 나타내고,

는 오른쪽 다리의 스트라이드 길이의 평가값을 나타낼 수 있다. 또한,

는 왼쪽 다리에 제공되는 스트라이드 길이에 대한 피크 토크를 나타내고,

는 오른쪽 다리에 제공되는 스트라이드 길이에 대한 피크 토크를 나타내고,

는 왼쪽 다리에 제공되는 스트라이드 길이에 대한 초기 안정 보조력을 제공하는 소정의 시간을 나타내고,

는 오른쪽 다리에 제공되는 스트라이드 길이에 대한 초기 안정 보조력을 제공하는 소정의 시간을 나타낼 수 있다. 수학식 8에 따라, 안정 보조력 연산부는 시각 t에 따른 왼쪽 힙 관절의 각도의 궤적

와 시각 t에 따른 오른쪽 힙 관절의 각도의 궤적

을 이용하여 교차 시점을 추출하고, 교차 시점부터 소정의 시간

및

동안 왼쪽 다리와 오른쪽 다리가 서로 벌어지도록 피크 토크

및

를 제공할 수 있다.here,

Represents the initial stabilization assistance force for the stride length provided to the left leg at time t,

Represents the initial stabilization assistance force for the stride length provided to the right leg at time t,

Represents the trajectory of the angle of the left hip joint according to time t,

Represents the trajectory of the angle of the right hip joint according to time t,

represents the evaluation value of the stride length of the left leg,

may represent an evaluation value of the stride length of the right leg. also,

represents the peak torque for the stride length provided to the left leg,

represents the peak torque for the stride length provided to the right leg,

Represents a predetermined time to provide an initial stabilization assistance force for the stride length provided to the left leg,

may represent a predetermined time for providing an initial stabilization assistance force for a stride length provided to the right leg. According to Equation 8, the stabilization assistance force calculator calculates the trajectory of the angle of the left hip joint according to time t

and the trajectory of the angle of the right hip joint according to time t

Extract the intersection point using, and a predetermined time from the intersection point

and

peak torque so that the left and right legs are apart while

and

can provide.

In one embodiment, the stability assist force calculation unit extracts a point in time when the user's swinging leg approaches the ground, and uses a peak torque for a predetermined time from the point when the swinging leg approaches the ground to provide initial stability assistance for foot clearance. power can be set. Here, a predetermined time and peak torque may be set in advance. The stability assist force calculation unit may set an initial stability assist force for the foot clearance according to Equation 9 below.

[Equation 9]

는 시각 t에 따라 왼쪽 다리에 제공하는 풋 클리어런스에 대한 초기 안정 보조력을 나타내고,

는 시각 t에 따라 오른쪽 다리에 제공하는 풋 클리어런스에 대한 초기 안정 보조력을 나타내고,

은 시각 t에 따른 왼쪽 힙 관절의 각도의 궤적을 나타내고,

는 시각 t에 따른 오른쪽 힙 관절의 각도의 궤적을 나타내고,

은 왼쪽 다리의 풋 클리어런스의 평가값을 나타내고,

은 오른쪽 다리의 풋 클리어런스의 평가값을 나타낼 수 있다. 또한,

은 왼쪽 다리에 제공되는 풋 클리어런스에 대한 피크 토크를 나타내고,

은 오른쪽 다리에 제공되는 풋 클리어런스에 대한 피크 토크를 나타내고,

는 왼쪽 다리에 제공되는 풋 클리어런스에 대한 초기 안정 보조력을 제공하는 소정의 시간을 나타내고,

는 오른쪽 다리에 제공되는 풋 클리어런스에 대한 초기 안정 보조력을 제공하는 소정의 시간을 나타낼 수 있다. 수학식 9에 따라, 안정 보조력 연산부는 왼쪽 힙 관절의 각도의 궤적

와 시각 t에 따른 오른쪽 힙 관절의 각도의 궤적

을 이용하여 사용자의 스윙하는 다리가 지면에 다가가는 시점을 추정하고, 사용자의 스윙하는 다리가 지면에 다가가는 시점부터 소정의 시간

및

동안 왼쪽 다리 및 오른쪽 다리를 더 높여주도록 피크 토크

및

를 제공할 수 있다.here,

Represents the initial stabilization assistance force for the foot clearance provided to the left leg at time t,

Represents the initial stabilization assistance force for the foot clearance provided to the right leg at time t,

Represents the trajectory of the angle of the left hip joint according to time t,

Represents the trajectory of the angle of the right hip joint according to time t,

represents the evaluation value of the foot clearance of the left leg,

may represent an evaluation value of the foot clearance of the right leg. also,

represents the peak torque for the foot clearance provided to the left leg,

represents the peak torque for the foot clearance provided to the right leg,

Represents a predetermined time to provide an initial stabilization assistance force for foot clearance provided to the left leg,

may represent a predetermined time to provide an initial stabilization assistance force for foot clearance provided to the right leg. According to Equation 9, the stabilization assistance force calculator calculates the trajectory of the angle of the left hip joint

and the trajectory of the angle of the right hip joint according to time t

The time point at which the user's swinging leg approaches the ground is estimated using

and

peak torque to elevate the left and right legs while

and

can provide.

In addition, the stability assist force calculator may set the stability assist force by applying a weight to the initial stability assist force for each at least one index. In one embodiment, the stability assist force calculation unit may determine the stability assist force using Equation 10 below.

[Equation 10]

은 n번째 스트라이드에 왼쪽(오른쪽) 다리에 제공되는 안정 보조력을 나타내고,

는 왼쪽(오른쪽) 다리의 인덱스 i의 k번째 가중치를 나타내고,

는 왼쪽(오른쪽) 다리에 제공되는 인덱스 i에 대한 초기 안정 보조력을 나타낼 수 있다.here,

Represents the stabilization assistance force provided to the left (right) leg at the nth stride,

represents the k-th weight of index i of the left (right) leg,

may represent the initial stabilizing force for index i provided to the left (right) leg.

In one embodiment, the stability assist force calculation unit may set the stability assist force in a cycle of one stride. In this case, a cycle in which the evaluation value and the weight are calculated may be different for each index. For example, the stability assist force calculation unit may calculate an evaluation value and weight for gait symmetry for each stride, and may calculate an evaluation value and weight for stride length and foot clearance for every 100 strides. In this case, when the stability assist force calculation unit sets the stability assist force in a cycle of one stride, the evaluation value and weight for gait symmetry are calculated for each stride, using the calculated value, and evaluation of the stride length and foot clearance Values and weights may use previously calculated values.

The basic assisting force setting unit 230 may set the basic assisting force according to the user's gait motion based on the gait data. Here, the basic assisting force may refer to an assisting force that is basically set by the assisting force setting device 200 to assist the user's walking without considering the evaluation value of at least one index. The basic assisting force setting unit 230 may set the basic assisting force using an Adaptive Oscillator (AO) based basic assisting force setting technique or a Finite State Machine (FSM) based basic assisting force setting technique. there is. At this time, which of the AO-based basic assisting force setting technique or the FSM-based basic assisting force setting technique to be selected by the basic assisting force setting unit 230 may be selected from the outside through a communication interface, The basic assisting force setting unit 230 may analyze and select the user's muscle strength level or gait pattern.

In the case of the AO-based basic assistance force setting technique, the basic assistance force setting unit 230 applies gait data to AO to estimate the periodicity (eg, frequency pattern, phase pattern) of the user's gait motion, and gait The auxiliary force corresponding to the periodicity of the operation may be set as the basic auxiliary force. At this time, the assisting force corresponding to each periodicity may be set in advance. For example, the basic assisting force set according to the AO-based basic assisting force setting technique may be suitable for a user who regularly walks or a user who walks at a walking speed of a normal pedestrian.

In the case of the FSM-based assist force setting technique, the basic assist force setting unit 230 may model a plurality of gait states in advance, and the user's gait motion and A corresponding walking state may be recognized. Also, the basic assisting force setting unit 230 may set the assisting force according to the recognized walking state as the basic assisting force. At this time, the assisting force corresponding to each gait state may be set in advance. For example, the basic assisting force set according to the FSM-based basic assisting force setting technique may be suitable for a user who walks irregularly or a user who cannot walk at a walking speed of a normal pedestrian.

Also, the assisting force setting device 200 may further include a gait motion recognition unit that recognizes a user's gait motion based on gait data.

The gait motion recognition unit may determine whether the user performs a gait motion based on the gait data. When the gait motion recognizing unit determines that the user performs a gait motion, the basic assisting force setting unit 230 may set the basic assisting force based on the gait data. Also, when the gait motion recognition unit determines that the user does not perform the gait motion, the basic assisting force setting unit 230 may set the basic assisting force to zero.

The final assisting force setting unit 240 may set the final assisting force based on the basic assisting force and the stability assisting force. In one embodiment, the final assisting force setting unit 240 may set the final assisting force by adding the basic assisting force and the stability assisting force. In addition, the final assisting force setting unit 240 may set a value having a larger absolute value among the basic assisting force and the stability assisting force as the final assisting force. Also, in another embodiment, the final assisting force setting unit 240 may set only the stabilizing assisting force as the final assisting force. In addition, the present invention is not limited thereto, and the final assisting force setting unit 240 may set the final assisting force by combining the basic assisting force and the stability assisting force in another method.

In one embodiment, the final assisting force setting unit 240 transmits information on the stability assisting force, information on the basic assisting force, or information on the final assisting force to an external device (eg, an external device) using a communication interface. walking assistance device, server).

Also, the final assisting force setting unit 240 may control the walking assisting device so that the walking assisting device outputs a stable assisting force or a final assisting force. Accordingly, the walking assistance device controlled by the final assisting force setting unit 240 assists the user to walk stably according to the stabilizing assisting force or the final assisting force, thereby preventing the user from falling.

3 is a block diagram illustrating an assisting force setting device according to another exemplary embodiment.

Referring to FIG. 3 , the assisting force setting device 300 includes an index evaluation unit 310 , a weight calculating unit 320 and an assisting force setting unit 330 .

The index evaluator 310 may calculate an evaluation value of at least one index representing the user's gait stability based on the user's gait data. Here, the at least one index may include at least one of gait symmetry, stride length, stride width, foot clearance, landing speed, or gait ratio.

The index evaluator 310 may classify the gait data based on the stride and calculate an evaluation value of at least one index based on the classified gait data. At this time, the index evaluator 310 calculates the evaluation value of the gait symmetry using Equation 1 described above, calculates the evaluation value of the stride length using Equation 2 described above, and calculates the evaluation value of the gait symmetry using Equation 3 described above. The evaluation value of the foot clearance can be calculated using In addition, the index evaluator 310 may determine whether the user's gait is stable based on each index by comparing the evaluation value and the threshold value for each index.

The weight calculation unit 320 may calculate a weight for at least one index based on a difference between an evaluation value of at least one index and a threshold value corresponding to the at least one index. At this time, the weight calculator 320 may calculate a weight for at least one index by normalizing a difference between an evaluation value of at least one index and a threshold value corresponding to at least one index, as in Equation 4 described above. there is.

The assisting force setting unit 330 may set the stabilizing assisting force by applying a weight to the initial stabilizing assisting force corresponding to at least one index.

The assisting force setting unit 330 may set an initial stabilizing assisting force based on the gait data and apply a weight to the initial stabilizing assisting force to set the stabilizing assisting force. For example, the assisting force setting unit 330 sets the initial stabilizing assisting force for the gait symmetry using Equation 7 described above, and sets the initial stabilizing assisting force for the stride length using Equation 8 described above, , it is possible to set the initial stabilization assistance force for the foot clearance using the above-described Equation 9.

Also, the assisting force setting unit 330 may set the stabilizing assisting force by applying a weight to the initial stabilizing assisting force for each at least one index. For example, the assisting force setting unit 330 may determine the stabilizing assisting force using Equation 10 described above.

Also, the assisting force setting device 300 may include a basic assisting force setting unit that sets the basic assisting force according to the user's gait motion based on the gait data.

The basic assisting force setting unit sets the basic assisting force according to the user's gait motion based on the gait data. The basic assisting force setting unit may set the basic assisting force using an AO-based basic assisting force setting technique or an FSM-based basic assisting force setting technique. At this time, whether the basic assisting force setting unit selects which of the AO-based basic assisting force setting technique or the FSM-based basic assisting force setting technique is selected from the outside through a communication interface, and the basic assisting force setting An additional user's muscle strength level or gait pattern may be analyzed and selected.

In the case of the AO-based basic assistive force setting technique, the basic assistive force setter may apply gait data to AO to estimate the periodicity of the user's gait motion, and set the assistive force corresponding to the periodicity of the gait motion as the basic assistive force. there is.

In the case of the FSM-based assist force setting technique, the basic assist force setting unit can model a plurality of gait states in advance, and the gait state corresponding to the user's gait motion among the plurality of gait states modeled by applying the gait data to the FSM can recognize Also, the basic assisting force setter may set the assisting force according to the recognized walking state as the basic assisting force.

Also, the assisting force setting unit 330 may set the final assisting force based on the basic assisting force and the stability assisting force. In one embodiment, the assisting force setting unit 330 may set the final assisting force by adding the basic assisting force and the stability assisting force. In addition, the assisting force setting unit 330 may set a value having a larger absolute value among the basic assisting force and the stability assisting force as the final assisting force. Also, in another embodiment, the assisting force setting unit 330 may set only the stabilizing assisting force as the final assisting force. In addition, the present invention is not limited thereto, and the assisting force setting unit 330 may set the final assisting force by combining the basic assisting force and the stability assisting force in another method.

4 is a block diagram illustrating an assisting force setting device according to another exemplary embodiment.

Referring to FIG. 4 , the assisting force setting device 400 includes a gait data extracting unit 410, a motion estimation unit 420, a selection unit 430, a basic assisting force setting unit 440, a stability assisting force setting unit ( 450) and a final assisting force setting unit 460.

The gait data extraction unit 410 includes a hip joint estimation unit 411 and a direction estimation unit 412 . The hip joint estimator 411 may estimate information about angles of both hip joints, velocities of both hip joints, and angular velocities of both hip joints. For example, the hip joint estimator 411 may receive 2-axis joint angle data and 2-axis joint angular velocity data from a potentiometer. As another example, the hip joint estimator 411 may receive information about angles, velocities, or angular velocities of both hip joints from a motor encoder. The hip joint estimator 411 may estimate information about the hip joint using information received from the potentiometer or motor encoder.

The direction estimator 412 may estimate information about movement directions of both hip joints. For example, the direction estimator 420 receives X-axis, Y-axis, and Z-axis acceleration data and X-axis, Y-axis, and Z-axis angular velocity data according to the user's walking motion from the IMU sensor, and receives data from the IMU sensor. The motion direction of both hip joints can be estimated using the data.

The motion estimation unit 420 includes a motion reconstruction unit 421 , a motion recognition unit 422 and an environment recognition unit 423 . The motion reconstruction unit 421 may estimate the user's posture using the gait data acquired by the gait data extractor 410 . For example, the motion reconstruction unit 421 may estimate the posture of the knee or ankle using the information on the hip joint acquired by the hip joint estimator 411 .

The motion recognition unit 422 may estimate a user's motion (eg, a standing motion, a sitting motion, or a walking motion) using the gait data acquired by the gait data extractor 410 .

The environment recognizer 423 may estimate the user's walking environment using the gait data acquired by the gait data extractor 410 . For example, the environment recognizing unit 423 may recognize a flat environment, an upslope environment, a downslope environment, an upstairs environment, and a downstairs environment using the gait data acquired by the gait data extractor 410 . In addition, it is not limited thereto, and the environment recognition unit 423 may recognize other walking environments in addition to the aforementioned five walking environments.

The selector 430 selects a technique for setting the basic assisting force. For example, the selector 430 may select an AO-based basic assisting force setting technique or an FSM-based basic assisting force setting technique. At this time, the selection unit 430 may receive selection of a basic assisting force setting technique from the outside through a communication interface, or may analyze and select a user's muscle strength level or gait pattern.

The basic assisting force setting unit 440 includes a gait cycle estimating unit 441, a first basic assisting force setting unit 442, a gait state recognition unit 443, and a second basic assisting force setting unit 444.

When the AO-based basic assistance force setting technique is selected by the selector 430, the gait period estimation unit 441 may estimate the periodicity of the user's gait motion by applying gait data to the AO. For example, the gait cycle estimator 441 may apply gait data to AO to extract a periodic frequency pattern or phase pattern according to the user's gait. The first basic assisting force setter 442 may set the assisting force corresponding to the periodicity of the walking motion as the basic assisting force. For example, the first basic assisting force setting unit 442 may preset a plurality of frequency (phase) patterns and an assisting force corresponding to each of the plurality of frequency (phase) patterns. The first basic assist force setting unit 442 extracts a frequency (phase) pattern corresponding to the frequency (phase) pattern estimated by the gait period estimation unit 441 from among a plurality of frequency (phase) patterns, and extracts a plurality of frequency (phase) patterns. The auxiliary force corresponding to the extracted frequency (phase) pattern may be extracted from the auxiliary force corresponding to each phase) pattern.

When the FSM-based basic assistance force setting technique is selected by the selector 430, the gait cycle estimation unit 441 recognizes a gait state corresponding to the user's gait motion among a plurality of gait states modeled by applying gait data to the FSM. can do. For example, the gait state recognizer 443 may model a plurality of gait states in advance. For example, the gait state recognition unit 443 may classify the gait state into a state in which the right leg swings, a state in which both legs cross each other, and a state in which the left leg swings, and may model the classified gait state. The gait state recognition unit 443 may recognize the user's gait state by applying the gait data to the FSM. In addition, the gait state recognition unit 443 may recognize the user's gait state using the user's posture estimated by the motion reconstruction unit 421 . The gait state recognition unit 443 may extract a gait state corresponding to the recognized gait state from among a plurality of modeled gait states.

The second basic assisting force setter 444 may set the assisting force corresponding to the extracted walking state among the plurality of modeled walking states as the basic assisting force. At this time, the assisting force corresponding to each gait state may be set in advance.

The stability assist force setting unit 450 includes an index evaluation unit 451 , a weight calculation unit 452 and a stability assist force determination unit 453 .

The index evaluator 451 may classify the gait data based on the stride and calculate an evaluation value of at least one index based on the classified gait data. At this time, the index evaluation unit 451 calculates the evaluation value of the gait symmetry using Equation 1 described above, calculates the evaluation value of the stride length using Equation 2 described above, and calculates the evaluation value of the gait symmetry using Equation 3 described above. The evaluation value of the foot clearance can be calculated using In addition, the index evaluator 451 may determine whether the user's gait is stable based on each index by comparing the evaluation value and the threshold value for each index.

In one embodiment, when the motion recognition unit 422 recognizes that the user is not walking, it is not necessary to set the stability assist force, so the index evaluation unit 451 does not calculate an evaluation value for at least one index. may not be

The weight calculator 452 may calculate a weight for at least one index based on a difference between an evaluation value of at least one index and a threshold value corresponding to the at least one index. At this time, the weight calculation unit 452 may calculate the weight for the at least one index by normalizing the difference between the evaluation value of the at least one index and the threshold value corresponding to the at least one index, as in Equation 4 described above. there is. The stability assist force determiner 453 may set an initial stability assist force based on the gait data and apply a weight to the initial stability assist force to set the stability assist force. For example, the stability assist force determiner 453 sets the initial stability assist force for the gait symmetry using Equation 7 described above, and sets the initial stability assist force for the stride length using Equation 8 described above. And, it is possible to set the initial stabilization assistance force for the foot clearance using the above-described Equation 9.

The stability assist force determiner 453 may determine the stability assist force by applying a weight to the initial stability assist force for each at least one index. For example, the stability assist force determiner 453 may determine the stability assist force using Equation 10 described above.

The final assisting force setting unit 460 may set the final assisting force based on the basic assisting force set by the basic assisting force setting unit 440 and the stability assisting force set by the stability assisting force setting unit 450 . The final assisting force setter 460 may set the final assisting force by adding the basic assisting force and the stability assisting force, or may set the final assisting force to a value having a larger absolute value among the basic assisting force and the stability assisting force. Also, the final assisting force setting unit 460 may set only the stabilizing assisting force as the final assisting force.

5 is an operation flowchart illustrating setting of a final assisting force according to an exemplary embodiment.

Referring to FIG. 5 , the assisting force setting device recognizes the user's gait motion (510). The assisting force setting device may obtain gait data from a sensor that senses the user's motion and estimate the user's motion using the acquired gait data.

The assisting force setting device determines whether the user is walking (520). When it is determined that the user does not walk, the assisting force setting device sets the stabilizing assisting force to 0 (560).

When it is determined that the user is walking, the assisting force setting device calculates an evaluation value of at least one index (530). For example, the assisting force setting device calculates an evaluation value of gait symmetry using Equation 1 described above, calculates an evaluation value of a stride length using Equation 2 described above, and calculates an evaluation value of a stride length using Equation 3 described above. An evaluation value of the foot clearance can be calculated.

Also, the assisting force setting device calculates a weight for at least one index (540). The assisting force setting device may calculate a weight for at least one index based on a difference between an evaluation value of at least one index and a threshold value corresponding to the at least one index. At this time, the assisting force setting device may calculate the weight for the at least one index by normalizing the difference between the evaluation value of the at least one index and the threshold value corresponding to the at least one index, as in Equation 4 described above. .

In addition, the assisting force setting device sets a stable assisting force (550). The assisting force setting device may set an initial stabilizing assist force based on the gait data and set the stabilizing assist force by applying a weight to the initial stabilizing assist force. For example, the assisting force setting apparatus sets the initial stabilizing assisting force for the gait symmetry using Equation 7 described above, sets the initial stabilizing assisting force for the stride length using Equation 8 described above, and An initial stabilization assist force for the foot clearance may be set using Equation 9. In addition, the assisting force setting apparatus may set the stabilizing assisting force by applying a weight to the initial stabilizing assisting force for each at least one index. For example, the assisting force setting device may determine the stabilizing assisting force using Equation 10 described above.

Also, the assisting force setting apparatus sets a basic assisting force according to the user's gait motion based on the gait data (570). The assisting force setting device may set the basic assisting force using an AO-based basic assisting force setting technique or an FSM-based basic assisting force setting technique. In the case of the AO-based basic assistive force setting technique, the assistive force setting device may apply gait data to the AO to estimate the periodicity of the user's gait motion and set the assistive force corresponding to the periodicity of the gait motion as the basic assistive force. there is. In the case of the FSM-based assistive force setting technique, the assistive force setting device may model a plurality of gait states in advance, and apply gait data to the FSM to obtain a gait corresponding to the user's gait motion among the plurality of modeled gait states. status can be recognized. Also, the basic assisting force setter may set the assisting force according to the recognized walking state as the basic assisting force.

In addition, the assisting force setting device sets the final assisting force by combining the stabilizing assisting force and the basic assisting force (580). The assisting force setting device may set the final assisting force by adding the basic assisting force and the stability assisting force, or may set the final assisting force to a value having a larger absolute value among the basic assisting force and the stability assisting force. Also, the assisting force setting device may set only the stabilizing assisting force as the final assisting force.

6 is a diagram for explaining setting of a basic assisting force according to an exemplary embodiment.

Referring to FIG. 6 , a graph represents a change in gait data according to a user's gait. The horizontal axis of the graph represents time, and the vertical axis represents the hip joint angle or hip joint velocity.

At time point 611, the right leg may stop swinging, at time point 612, the left leg may swing and cross the right leg, at time point 613, the left leg may stop swinging, and at time point 614, the right leg may swing and cross the left leg. can intersect, and at point 615, the right leg can stop swinging as in point 611. In other words, the gait motions from time points 611 to 615 represent strides, the gait motions from time points 611 to 613 represent steps for the right leg, and the gait motions from time points 613 to 615 represent steps for the left leg. can represent A dotted line 621 may indicate a left hip joint angle, a solid line 622 may indicate a right hip joint angle, a dotted line 631 may indicate a left hip joint speed, and a solid line 632 may indicate a right hip joint speed.

In one embodiment, the assisting force setting device may model each of the four gait states at points in time 611 , 612 , 613 , and 614 in advance. The assistive force setting device applies both hip joint angle information (621, 622) and both hip joint velocity information (631, 632) to the FSM according to the FSM-based assistive force setting technique, and the user's A walking state corresponding to the walking motion may be recognized. In addition, the assistive force setting device may preset assistive force corresponding to the four modeled gait states, and the assistive force setting device may set the assistive force according to the gait state recognized as the user's gait motion among the four modeled gait states. It can be set as the default auxiliary power.

In another embodiment, the assistive force setting device applies both hip joint angle information 621 and 622 and both hip joint speed information 631 and 632 to the AO according to the AO-based basic assistive force setting technique to determine the user's The periodicity (eg, phase pattern) of the gait motion may be estimated. The assisting force setting device may preset an assisting force corresponding to each periodicity, and may set an assisting force corresponding to the estimated periodicity of a walking motion as a basic assisting force.

7 is a diagram for explaining calculation of an evaluation value for gait symmetry according to an exemplary embodiment.

Referring to FIG. 7 , graph (a) shows a change in a hip joint angle according to a user's walking. In graph (a), the horizontal axis represents time, and the vertical axis represents the hip joint angle.

At time point 711 the left leg may stop swinging, at time point 712 the right leg may swing and cross the left leg, at time point 713 the right leg may stop swinging, at time point 714 the left leg may swing and the right leg may swing can intersect, and at point 715 the left leg can stop swinging. Also, at a time point 716, the right leg may swing and cross the left leg, and at a time point 717, the right leg may stop swinging as in a time point 713. The walking motions at time points 711 to 715 represent one stride for the right leg, and the walking motions at time points 713 to 717 represent one stride for the left leg. Also, the walking motions from time points 711 to 713 and the walking motions from time points 715 to 717 represent steps of the left leg, and walking movements from time points 713 to 715 represent steps of the right leg. A solid line 721 represents a right hip joint angle, and a dotted line 722 represents a left hip joint angle.

The assisting force setting apparatus may estimate a similarity between the right hip joint angle trajectory 721 and the left hip joint angle trajectory 722 and determine the estimated similarity as an evaluation value of gait symmetry. The assisting force setting device may calculate a difference between the trajectory of the angle of the right hip joint from time points 711 to 715 and the trajectory of the angle of the left hip joint from time points 713 to 717 . At this time, the locus of the right hip joint angle from time points 711 to 715 and the trajectory of the left hip joint angle from time points 713 to 717 may be one step interval.

Graph (b) shows a difference 733 between the trajectory of the angle of the right hip joint from time points 711 to 715 (solid line 731) and the trajectory of the angle of the left hip joint from time points 713 to 717 (dotted line 732). In graph (b), the horizontal axis represents NST, and the vertical axis represents the hip joint angle.

The assisting force setting device may calculate an evaluation value of gait symmetry using Equation 1 described above. The assist force setting device applies dynamic time warping to the difference (733) between the trajectory of the right hip joint angle (731) and the trajectory of the left hip joint angle (732) to determine the trajectory of the right hip joint angle (731) and the left hip joint angle. The similarity of the trajectory 732 may be estimated, and the estimated similarity may be calculated as an evaluation value of gait symmetry at time points 711 to 717 . Also, the assisting force setting device may determine whether the user's gait is stable based on the gait symmetry by comparing the evaluation value with a threshold value for the gait symmetry.

8 is a diagram for explaining setting of an initial stability assist force for gait symmetry according to an exemplary embodiment.

Referring to FIG. 8 , graph (a) shows a change in the hip joint angle according to the user's walking, and graph (b) shows the initial stability assist force according to the user's walking. In graph (a), the horizontal axis represents NST, and the vertical axis represents the hip joint angle. In the graph (b), the horizontal axis represents NST, and the vertical axis represents initial stability assistance force.

At time point 811, the right leg may stop swinging, at time point 812, the left leg may swing and cross the right leg, at time point 813, the left leg may stop swinging, and at time point 814, the right leg may swing and cross the left leg. can intersect, and at time point 815, the right leg can stop swinging as at time point 811. The gait motions from time points 811 to 815 represent strides, the gait motions from time points 811 to 813 represent steps for the right leg, and the gait motions from time points 813 to 815 represent steps for the left leg. there is.

In graph (a), solid line 821 represents the right hip joint angle, dotted line 822 represents the left hip joint angle, in graph (b), solid line 861 represents the initial stabilizing force provided to the right leg, and dotted line 862 represents It can represent the initial stabilization assistance provided to the left leg.

The assisting force setting device multiplies the difference between the trajectory 821 of the right hip joint angle and the trajectory 822 of the left hip joint angle shown on the NST axis by a predetermined gain according to Equations 5 to 7 described above, thereby obtaining an initial stabilizing assist force. can be set. In order to set the initial stabilization assistance force 861 provided to the right leg, the assistance force setting device subtracts the trajectory 821 of the right hip joint angle from the trajectory 822 of the left hip joint angle, which is provided to the right leg. It can be multiplied by the gain of the initial stability assist force. In addition, in order to set the initial stabilization assistance force 862 provided to the left leg, the assistance force setting device subtracts the trajectory 822 of the left hip joint angle from the trajectory 821 of the right hip joint angle, and It can be multiplied by the gain of the initial stability assist force provided.

An initial stabilization assist force for the right leg may be applied from a time point 811, and an initial stabilization assist force for the left leg may be applied from a time point 813.

Accordingly, the assisting force setting device provides the initial stabilizing force 861 provided to the right leg and the left leg so that the difference between the trajectory 822 of the left hip joint angle and the trajectory 821 of the right hip joint angle is offset. An initial stability assist force 862 may be set.

9 is a diagram for explaining setting of an initial stabilization assist force with respect to a stride length according to an exemplary embodiment.

Referring to FIG. 9 , a graph shows an initial stability assistance force according to a user's walking. The horizontal axis of the graph represents NST, and the vertical axis represents initial stabilization assistance force.

At time point 911, the right leg may stop swinging, at time point 912, the left leg may swing and cross the right leg, at time point 913, the left leg may stop swinging, and at time point 914, the right leg may swing and cross the left leg. can intersect, and at point 915, the right leg can stop swinging as in point 911. The gait motions from time points 911 to 915 may represent strides, the gait motions from time points 911 to 913 may represent steps for the right leg, and the gait motions from time points 913 to 915 may represent steps for the left leg. there is. In the graph, a solid line 921 may indicate an initial stability assist force provided to the right leg, and a dotted line 922 may indicate an initial stability assist force provided to the left leg.

According to the above-described Equation 8, the assisting force setting device extracts the point of intersection of the right leg and the left leg using the trajectory of the angle of the left hip joint and the trajectory of the angle of the right hip joint, and for a predetermined time from the point of intersection The peak torque of can be set as the initial stabilizing assist force for the stride length. Here, a predetermined time and peak torque may be set in advance. In the example of FIG. 9 , the assisting force setting device may extract the viewpoints 912 and 914 as the intersection viewpoints of the right leg and the left leg. The assisting force setting device provides an initial stabilization assist force 921 provided to the right leg and an initial stabilization assist force 922 provided to the left leg to provide peak torque to the left leg and right leg for a predetermined time from time points 912 and 914. ) can be set. Accordingly, the assisting force setting device provides an initial stabilization assist force 921 provided to the right leg and an initial stabilization assist force provided to the left leg ( 922) can be set.

10 is a diagram for explaining setting of an initial stabilizing assist force for foot clearance according to an embodiment.

Referring to FIG. 10 , a graph shows an initial stability assistance force according to a user's walking. The horizontal axis of the graph represents NST, and the vertical axis represents initial stabilization assistance force.

At time point 1011 the right leg can stop swinging, at time point 1012 the left leg can swing and cross the right leg, at time point 1013 the left leg can stop swinging, at time point 1014 the right leg can swing and cross the left leg , and at point 1015, the right leg can stop swinging as in point 1011. The gait motions from time points 1011 to 1015 may represent strides, the gait motions from time points 1011 to 1013 may represent steps for the right leg, and the gait motions from time points 1013 to 1015 may represent steps for the left leg. there is. In the graph, a solid line 1021 may indicate an initial stability assist force provided to the right leg, and a dotted line 1022 may indicate an initial stability assist force provided to the left leg.

According to Equation 9 above, the assisting force setting device extracts the point in time when the swinging leg of the user approaches the ground using the trajectory of the angle of the left hip joint and the trajectory of the angle of the right hip joint, and determines whether the swinging leg is The peak torque for a predetermined time from the point of approaching the ground may be set as the initial stabilizing force for the foot clearance. Here, a predetermined time and peak torque may be set in advance. In the example of FIG. 10 , the assisting force setting device extracts a time point between points 1012 and 1013 as the point in time when the left leg approaches the ground, and sets a point in time between points 1014 and 1015 as the point in time when the right leg approaches the ground. can be extracted.

The assisting force setting device sets the initial stabilizing assisting force 1022 provided to the left leg to provide a peak torque to the left leg for a predetermined time from a time point between time points 1012 and 1013, and a time point between time points 1014 and 1015. An initial stabilizing force 1021 provided to the right leg may be set so as to provide peak torque to the right leg for a predetermined period of time. Accordingly, the assisting force setting device sets the initial stabilization assisting force 1022 to further raise the left leg for a predetermined time from the time point between time points 1012 and 1013, and for a predetermined time from the time point between time points 1014 and 1015. The initial stabilization assistance force 1021 may be set so as to further raise the right leg during the operation.

11 is a diagram for explaining setting of an assisting force according to an exemplary embodiment.

Referring to FIG. 11 , the assisting force setting device may be included in a walking assistance device 1110 or an external device (eg, server) 1120 .

In one embodiment, when the assistive force setting device is included in the walking assistance device 1110, the assistive force setting device senses a change in the amount of motion of the user according to the walking motion from a sensor included in the walking assistive device 1110. data can be received. The assisting power setting device may calculate an evaluation value of at least one index based on the gait data, and calculate a weight for at least one index based on a difference between the evaluation value and a threshold value corresponding to the at least one index. . At this time, the assisting force setting device may receive information on a threshold value corresponding to at least one index from the external device 1120 through a communication interface. Also, the assisting force setting apparatus may set an initial stabilizing assisting force corresponding to at least one index based on the gait data, and set the stabilizing assisting force by applying a weight to the initial stabilizing assisting force. The assisting force setting device may set a basic assisting force based on the gait data, and may set a final assisting force by combining the basic assisting force and the stability assisting force. The assisting force setting device may control the walking assistance device 1110 to output a final assisting force. Also, the assisting force setting device may transmit the user's gait data, an evaluation value of at least one index, a weight, an initial stable assisting force, a basic assisting force, and a final assisting force to the external device 1120 through a communication interface.

In another embodiment, when the assistive force setting device is included in the external device 1120, the assistive force setting device uses a communication interface to detect a change in the user's momentum by a sensor included in the walking assistive device 1110. One gait data may be received from the walking assistance device 1110 . The assisting force setting device calculates an evaluation value of at least one index based on the received gait data, and calculates a weight for at least one index based on a difference between the evaluation value and a threshold value corresponding to the at least one index. can Here, a threshold value corresponding to at least one index may be predetermined. Also, the assisting force setting apparatus may set an initial stabilizing assisting force corresponding to at least one index based on the gait data, and set the stabilizing assisting force by applying a weight to the initial stabilizing assisting force. The assisting force setting device may set a basic assisting force based on the gait data, and may set a final assisting force by combining the basic assisting force and the stability assisting force. The assisting force setting device may transmit a control signal to the walking assisting device 1110 through a communication interface so that the walking assisting device 1110 is driven according to the final assisting force. The walking assistance device 1110 may output a final assisting force according to a control signal.

12 is a diagram for explaining an interface for providing an assisting force according to an exemplary embodiment.

Referring to FIG. 12 , the walking assistance device 1210 may receive an operation mode selected from the wearable device 1220 or the mobile device 1230 using a communication interface.

According to one aspect, the operating mode may include a first operating mode and a second operating mode. The first operation mode may be a mode in which the walking assistance device 1210 provides the user with assistance for walking. The second operation mode may be a mode in which the walking assistance device 1210 provides an assisting force to prevent a user from falling.

For example, when the first operation mode is selected, an assisting force for preventing a fall may not be considered. As another example, when the second operation mode is selected, the walking assistance device 1210 may calculate the final assisting force considering both the assisting force for walking and the assisting force for preventing a fall.

According to another aspect, the walking assistance device 1210 may receive gait data obtained by sensing a change in an amount of exercise of the user according to a gait motion from a sensor (not shown). The sensor may be connected to the walking assistance device 1210 through wired communication or wireless communication.

The walking assistance device 1210 may calculate an evaluation value of an index based on gait data. The walking assistance device 1210 may calculate a weight for an index based on a difference between an evaluation value and a threshold value corresponding to the index. The walking assistance device 1210 may set an initial stability assist force corresponding to the index based on the gait data, and apply a weight to the initial stability assist force to set the stability assist force. The walking assistance device 1210 may set a basic assisting force based on the gait data and may set a final assisting force by combining the basic assisting force and the stability assisting force. When the first mode is selected, the walking assistance device 1210 may output the set final assisting force.

According to another aspect, the walking assistance device 1210 transmits an evaluation value of an index, an initial stability assistance force, a stability assistance force, a basic assistance force, or a final assistance to the wearable device 1220 or the mobile device 1230 through a communication interface. information can be transmitted. The wearable device 1220 or the mobile device 1230 may display information received from the walking assistance device 1110 . For example, as in the example of FIG. 12 , the wearable device 1220 or the mobile device 1230 may display information indicating that the index for the stride length is reflected in order to set the final assisting force.

13 is a block diagram illustrating a walking assistance device according to an exemplary embodiment.

Referring to FIG. 13 , the walking assistance device 1300 includes a gait data receiving unit 1310, a stability assisting force setting unit 1320, a basic assisting force setting unit 1330, a final assisting force setting unit 1340, and a driving control unit ( 1350).

The gait data receiver 1310 receives gait data of the user.

The stability assist force setting unit 1320 sets the stability assist force using an evaluation value of at least one index based on gait data.

The basic assisting force setting unit 1330 sets the basic assisting force according to the user's gait motion based on the gait data.

The final assisting force setting unit 1340 sets the final assisting force based on the stability assisting force and the basic assisting force.

The gait data receiver 1310, the stability assist force setter 1320, the basic assist force setter 1330, and the final assist force setter 1340 include the gait data receiver 210 of FIG. 2 and the stability assist force setter ( 220), the basic assisting force setting unit 230, and the final assisting force setting unit 240 may be applied as they are, so a detailed description thereof will be omitted.

The driving controller 1350 may control driving of the walking assistance device based on the final assisting force. In one embodiment, the walking assistance device may include an actuator for driving both hip joints of the user, and may control the actuator to output a final assisting force. For example, the driving control unit 1350 may transmit a control signal to the actuator so that the actuator outputs a gain corresponding to the final assisting force. In this case, the driver may output a gain corresponding to the final assisting force according to the control signal. Accordingly, the walking assistance device assists the user to walk stably according to the final assisting force, thereby preventing the user from falling.

14 is a flowchart illustrating a method of setting an assisting force according to an exemplary embodiment.

Referring to FIG. 14 , the assisting force setting device may receive gait data of the user (1410).

Also, the assisting force setting device may set the stabilizing assisting force using an evaluation value of at least one index based on the gait data (1420).

Also, the assisting force setting device may set a basic assisting force according to the user's gait motion based on the gait data (1430).

Also, the assisting force setting device may set the final assisting force based on the stabilizing assisting force and the basic assisting force (1440).

Since the contents described with reference to FIGS. 1 to 13 may be applied to the assisting force setting method according to the embodiment shown in FIG. 14 as it is, a detailed description thereof will be omitted.

15 is a flowchart illustrating a method of setting an assisting force according to another exemplary embodiment.

Referring to FIG. 15 , the assistive power setting device may calculate an evaluation value of at least one index representing the user's gait stability based on the user's gait data (1510).

Also, the assisting power setting device may calculate a weight for at least one index based on a difference between the evaluation value and a threshold value corresponding to the at least one index (1520).

In addition, the assisting force setting apparatus may set the stabilizing assisting force by applying a weight to the initial stabilizing assisting force corresponding to at least one index (1530).

Since the contents described through FIGS. 1 to 13 may be applied to the assisting force setting method according to another embodiment shown in FIG. 15 as it is, a detailed description thereof will be omitted.

16 is a method flowchart illustrating a walking assistance method according to an exemplary embodiment.

Referring to FIG. 16 , the walking assistance device may receive walking data of the user (1610).

In addition, the walking assistance device may set the stabilizing assistance force by using an evaluation value of at least one index based on the walking data (1620).

Also, the walking assistance device may set a basic assisting force according to the user's walking motion based on the walking data (1630).

Also, the walking assistance device may set a final assisting force based on the stabilizing assisting force and the basic assisting force (1640).

Also, the walking assistance device may control driving of the walking assistance device based on the final assisting force (1650).

Since the contents described through FIGS. 1 to 13 may be applied to the walking assistance method according to another embodiment shown in FIG. 16 as it is, a detailed description thereof will be omitted.

As described above, although the embodiments have been described with limited examples and drawings, those skilled in the art can make various modifications and variations from the above description. For example, the described techniques may be performed in an order different from the method described, and/or components of the described system, structure, device, circuit, etc. may be combined or combined in a different form than the method described, or other components may be used. Or even if it is replaced or substituted by equivalents, appropriate results can be achieved.

Claims (28)

The auxiliary force setting device,
processor
including,
the processor,
Receive the user's gait data;
Classifying the gait data based on stride or step;
determining an evaluation value for at least one index representing the gait stability of the user based on the gait data classified based on the stride or the step;
determining whether the user's gait is stable based on the index based on the evaluation value and a threshold value corresponding to the index;
When it is determined that the user's gait is not stable based on the index, a stability assistance force is determined using the evaluation value for the index;
determining a basic assisting force according to the user's gait motion based on the gait data;
Setting a final assisting force based on the stabilizing assisting force and the basic assisting force,
Auxiliary force setting device.
According to claim 1,
the processor,
determining a weight for the index based on a difference between the evaluation value and the threshold;
Determining the stability assist force by applying the weight to the initial stability assist force corresponding to the index,
Auxiliary force setting device.
According to claim 2,
The index is
Gait symmetry indicating the degree of symmetry of both legs of the user, stride length and stride width of the user, and foot clearance indicating the distance between the user's feet and the ground clearance), including at least one of a landing speed or a walk ratio representing the speed at which the user's foot touches the ground,
Auxiliary force setting device.
delete delete According to claim 3,
the processor,
determining a similarity between a trajectory of a left hip joint angle and a trajectory of a right hip joint angle of the user based on the gait data;
Determining the degree of similarity as an evaluation value of the gait symmetry,
Auxiliary force setting device.
According to claim 6,
the processor,
Determining the similarity between the trajectory of the left hip joint angle and the trajectory of the right hip joint angle using Dynamic Time Warping (DTW),
Auxiliary force setting device.
According to claim 3,
the processor,
For a plurality of strides, determine an average stride length by calculating an average of a left hip joint angular range and an average of a right hip joint angular range based on the gait data;
Determining the average stride length as an evaluation value for the stride length,
Auxiliary force setting device.
According to claim 3,
the processor,
For a plurality of strides, determine a maximum flexion angle of a left hip joint and a maximum flexion angle of a right hip joint based on the gait data;
Determining the maximum bending angle of the left hip joint and the maximum bending angle of the right hip joint as evaluation values for the foot clearance,
Auxiliary force setting device.
According to claim 2,
the processor,
Normalize the difference between the evaluation value and the threshold value;
Calculating the weight based on the normalized difference,
Auxiliary force setting device.
According to claim 1,
the processor,
When the at least one index is plural, setting a partial stability assist force for the target index, for which it is determined that the user's gait is stable, to 0 based on the target index among the plurality of indices;
determining the stability assist force based on a plurality of partial stability assist forces for each of the plurality of indices;
Auxiliary force setting device.
According to claim 3,
the processor,
Setting the initial stability assist force based on the gait data,
Auxiliary force setting device.
According to claim 12,
the processor,
Setting the initial stabilizing force for the gait symmetry based on the difference between the trajectory of the left hip joint angle and the trajectory of the right hip joint angle among the gait data,
Auxiliary force setting device.
According to claim 12,
the processor,
determining a crossing time point at which the user's left leg and right leg intersect based on a trajectory of a left hip joint angle and a trajectory of a right hip joint angle among the gait data;
Setting a peak torque for a predetermined time from the crossing point as the initial stabilization assistance force for the stride length,
Auxiliary force setting device.
According to claim 12,
the processor,
determining a point in time when the swinging leg of the user approaches the ground based on a trajectory of a left hip joint angle and a trajectory of a right hip joint angle among the gait data;
Setting a peak torque for a predetermined time from the point at which the swinging leg approaches the ground as the initial stabilizing assistance force for the foot clearance,
Auxiliary force setting device.
According to claim 1,
the processor.
determining a gait motion of the user based on the gait data;
Setting the basic assistance force to 0 when it is determined that the user does not perform a walking motion.
Auxiliary force setting device.
According to claim 1,
the processor,
determining the periodicity of the user's gait motion by applying the gait data to an adaptive oscillator (AO);
Setting an assisting force corresponding to the periodicity of the walking motion as the basic assisting force,
Auxiliary force setting device.
According to claim 1,
the processor,
Modeling the user's gait motion into a plurality of states;
determining a gait state corresponding to the gait motion of the user among the plurality of modeled gait states by applying the gait data to a finite state machine (FSM);
Setting the assisting force according to the determined walking state as the basic assisting force,
Auxiliary force setting device.
According to claim 1,
the processor,
Setting the sum of the stability assist force and the basic assist force as the final assist force,
Auxiliary force setting device.
According to claim 1,
the processor,
Setting the larger absolute value of the stability assist force and the basic assist force as the final assist force,
Auxiliary force setting device.
The auxiliary force setting device,
processor
including,
the processor,
Classify the user's gait data based on stride or step;
determining an evaluation value for at least one index representing the gait stability of the user based on the gait data of the user classified based on the stride or the step;
determining whether the user's gait is stable based on the index based on the evaluation value and a threshold value corresponding to the index;
When it is determined that the user's gait is not stable based on the index, determining a weight for the index based on a difference between the evaluation value and the threshold value corresponding to the index;
Assisting force setting unit for setting the stabilizing assisting force by applying the weight to the initial stabilizing assisting force corresponding to the index
including,
Auxiliary force setting device.
According to claim 21,
the processor,
Setting the initial stability assist force based on the gait data,
Auxiliary force setting device.
According to claim 21,
the processor,
Based on the gait data, a basic assisting force according to the gait motion of the user is set;
Setting a final assisting force based on the basic assisting force and the stabilizing assisting force,
Auxiliary force setting device.
walking aids,
processor; and
A driving control unit controlling driving of the walking assistance device
including,
the processor,
Receive the user's gait data;
Classifying the gait data based on stride or step;
determining an evaluation value for at least one index representing the gait stability of the user based on the gait data classified based on the stride or the step;
determining whether the user's gait is stable based on the index based on the evaluation value and a threshold value corresponding to the index;
When it is determined that the user's gait is not stable based on the index, a stability assistance force is determined using the evaluation value for the index;
determining a basic assisting force according to the user's gait motion based on the gait data;
Determine a final assisting force based on the stabilizing assisting force and the basic assisting force;
Controlling the driving control unit based on the final assisting force,
walking aids.
Receiving user's gait data;
classifying the gait data based on strides or steps;
determining an evaluation value for at least one index representing the gait stability of the user based on the gait data classified based on the stride or the step;
determining whether the user's gait is stable based on the index based on the evaluation value and a threshold value corresponding to the index;
determining a stability assistance force using the evaluation value for the index when it is determined that the user's gait is not stable based on the index;
determining a basic assisting force according to the user's gait motion based on the gait data; and
Setting a final assisting force based on the stabilizing assisting force and the basic assisting force
including,
How to set the assist force.
classifying gait data of the user based on strides or steps;
determining an evaluation value for at least one index representing the gait stability of the user based on the gait data of the user classified based on the stride or the step;
determining whether the user's gait is stable based on the index based on the evaluation value and a threshold value corresponding to the index;
determining a weight for the index based on a difference between the evaluation value and the threshold corresponding to the index, when it is determined that the user's gait is not stable based on the index; and
Setting a stabilizing assist force by applying the weight to the initial stabilizing assist force corresponding to the index.
including,
How to set the assist force.
The walking assistance method performed by the walking assistance device includes:
Receiving user's gait data;
classifying the gait data based on strides or steps;
determining an evaluation value for at least one index representing the gait stability of the user based on the gait data classified based on the stride or the step;
determining whether the user's gait is stable based on the index based on the evaluation value and a threshold value corresponding to the index;
determining a stability assistance force using the evaluation value for the index when it is determined that the user's gait is not stable based on the index;
determining a basic assisting force according to the user's gait motion based on the gait data;
determining a final assisting force based on the stabilizing assisting force and the basic assisting force; and
Controlling driving of the walking assistance device based on the final assisting force
including,
Ambulation assist method.
A computer-readable recording medium on which a program for performing the method of any one of claims 25 to 27 is recorded.

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