CN114948579A

CN114948579A - Ankle exoskeleton and power-assisted control method and device thereof, and readable storage medium

Info

Publication number: CN114948579A
Application number: CN202111537471.2A
Authority: CN
Inventors: 付成龙; 冷雨泉; 马亮; 钱跃鹏; 张贶恩; 陈欣星
Original assignee: Southern University of Science and Technology
Current assignee: Southern University of Science and Technology
Priority date: 2021-12-15
Filing date: 2021-12-15
Publication date: 2022-08-30
Anticipated expiration: 2041-12-15
Also published as: CN114948579B

Abstract

The invention is applicable to the technical field of exoskeletons, and particularly relates to an ankle joint exoskeleton, a power-assisted control method and device thereof, and a readable storage medium. The power-assisted control method of the ankle exoskeleton comprises the following steps: acquiring left leg angle data and right leg angle data of a user, and determining a left leg angle difference and a right leg angle difference of the user; determining gait moments corresponding to the left and right leg angle differences based on the corresponding relation between the left and right leg angle differences and time of the previous step state period of the user; acquiring gait assistance delay time of a current gait cycle of a user; determining a power-assisted left-right leg angle difference corresponding to the left-right leg angle difference based on the gait time and the gait power-assisted delay time corresponding to the left-right leg angle difference in the corresponding relation between the left-right leg angle difference and the time; the power assisting value corresponding to the ankle joint exoskeleton is obtained through calculation based on the angle difference of the left leg and the right leg of the power assisting, the ankle joint exoskeleton is controlled to provide the power assisting based on the power assisting value, the exoskeleton power assisting value is directly calculated according to the angle difference data of the left leg and the right leg of a user, and the power assisting reliability is improved.

Description

Ankle exoskeleton and power-assisted control method and device thereof, and readable storage medium

Technical Field

The invention belongs to the technical field of exoskeleton, and particularly relates to an ankle exoskeleton, a power assisting control method and device thereof and a readable storage medium.

Background

The power-assisted ankle joint exoskeleton is an important exoskeleton and can assist the ankle joints of a human body to exert force, so that the walking ability of the human body is improved.

In general, the power assist control for an ankle exoskeleton is divided into three steps: current gait environment recognition, gait division and power-assisted control. The method comprises the steps of firstly determining the current gait environment of a user through a foot inertia measurement unit or a visual identification mode, then dividing the current gait, and finally giving different power-assisted curves for different gait environments.

However, this is a relatively clear tandem control method, and in the process of sensing, predicting and assisting, errors in any one of the environment recognition and gait division links may cause erroneous assisting in the assisting control link, and currently, the accuracy of the adopted technology is low, and the reliability of assisting is low.

Disclosure of Invention

The embodiment of the invention provides an ankle exoskeleton, an ankle exoskeleton power-assisted control method, an ankle exoskeleton power-assisted control device and a readable storage medium, which can solve the problems that in a traditional power-assisted control method, a gait environment needs to be identified in advance, and the power-assisted reliability is low.

In a first aspect, an embodiment of the present invention provides a power-assisted control method for an ankle exoskeleton, including:

acquiring left leg angle data and right leg angle data of a user, and determining a left leg angle difference and a right leg angle difference of the user;

determining gait moments corresponding to the left and right leg angle differences based on the corresponding relation between the left and right leg angle differences and time of the previous step state period of the user;

acquiring gait assistance delay time of the current gait cycle of the user;

determining a power-assisted left-right leg angle difference corresponding to the left-right leg angle difference based on the gait time corresponding to the left-right leg angle difference and the gait power-assisted delay time in the corresponding relation between the left-right leg angle difference and time;

and calculating a power assisting value corresponding to the ankle joint exoskeleton based on the power assisting left-right leg angle difference, and controlling the ankle joint exoskeleton to provide power assisting based on the power assisting value.

In a second aspect, an embodiment of the present invention provides a power assist control device for an ankle exoskeleton, including:

a first acquisition unit for acquiring left leg angle data and right leg angle data of a user and determining a left-right leg angle difference of the user;

the first determining unit is used for determining the gait moments corresponding to the left and right leg angle differences based on the corresponding relation between the left and right leg angle differences and the time of the previous step state period of the user;

the second acquisition unit is used for acquiring the gait assistance delay time of the current gait cycle of the user;

a second determining unit, configured to determine, in the correspondence between the left-right leg angle difference and time, a power-assisted left-right leg angle difference corresponding to the left-right leg angle difference based on a gait time corresponding to the left-right leg angle difference and the gait power-assisted delay time;

and the control unit is used for calculating a power assisting value corresponding to the ankle exoskeleton based on the power assisting left-right leg angle difference and controlling the ankle exoskeleton to provide power assisting based on the power assisting value.

In a third aspect, an embodiment of the present invention provides an ankle exoskeleton, including a driving box, an angle measuring device, a bowden cable, and a foot wearing component, where the angle measuring device is configured to collect left leg angle data and right leg angle data of a user, and the driving box is configured to perform the power-assisted control method of the first aspect, so as to control the bowden cable in the ankle exoskeleton to drive the foot wearing component to move so as to provide power assistance.

In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium, which stores a computer program, and when the computer program is executed by a processor, the computer program implements the steps of the method of the first aspect.

In the embodiment of the invention, the left leg angle data and the right leg angle data of a user are acquired, the left leg angle difference and the right leg angle difference of the user are determined, the gait time corresponding to the left leg angle difference and the right leg angle difference is determined based on the corresponding relation between the left leg angle difference and the right leg angle difference of the previous step state period of the user and the gait time corresponding to the left leg angle difference and the right leg angle difference of the current gait period of the user are acquired, the power-assisted left leg angle difference corresponding to the left leg angle difference and the right leg angle difference is determined based on the gait time corresponding to the left leg angle difference and the gait power-assisted delay time in the corresponding relation between the left leg angle difference and the right leg angle difference and the time corresponding to the left leg angle difference and the right leg angle difference are calculated to obtain the power-assisted value corresponding to the ankle joint exoskeleton, the ankle joint exoskeleton is controlled to provide power-assisted based on the power-assisted value, so that the use environment of the user is reflected through the angle difference data of the user (the use environment is different and the angle difference data of the user is correspondingly different) without carrying out gait environment recognition, and the current gait condition of the user is determined based on the corresponding relation between the angle difference of the left leg and the right leg of the previous step state period of the user and the time, and then the exoskeleton assistance value is calculated according to the angle difference data of the user, so that the determination of the assistance value does not depend on mode recognition such as visual recognition, and the reliability of ankle joint assistance is improved.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed for the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without inventive work.

Fig. 1 is a flowchart illustrating a power assist control method for an ankle exoskeleton according to an embodiment of the present invention;

FIG. 2 is a schematic illustration of a left leg angle and a right leg angle provided by an embodiment of the present invention;

FIG. 3 is a schematic diagram of an ankle exoskeleton according to an embodiment of the present invention;

FIG. 4 is a schematic illustration of determining an assist right and left leg angle difference based on a right and left leg angle difference, in accordance with an embodiment of the present invention;

fig. 5 is a schematic flowchart of a second implementation of a power-assisted control method for an ankle exoskeleton according to an embodiment of the present invention;

FIG. 6A is a schematic diagram of a left leg assist curve and a left leg angular difference versus time relationship in a gait cycle according to an embodiment of the invention;

FIG. 6B is a schematic diagram of a right leg assist curve and a right leg angular difference versus time relationship in a gait cycle according to an embodiment of the invention;

figure 6C is a schematic illustration of the power-assist curve for the ankle exoskeleton in one gait cycle, in accordance with an embodiment of the present invention.

Fig. 7 is a schematic structural diagram of an ankle exoskeleton assistance control device provided by an embodiment of the invention;

fig. 8 is a schematic structural diagram of a driving box in the ankle exoskeleton according to the embodiment of the invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. Meanwhile, in the description of the present invention, the terms "first", "second", and the like are used only for distinguishing the description, and are not to be construed as indicating or implying relative importance.

It will be understood that the terms "comprises" and/or "comprising," when used in this specification and the appended claims, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

It is also to be understood that the terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used in this specification and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

It should be further understood that the term "and/or" as used in this specification and the appended claims refers to any and all possible combinations of one or more of the associated listed items and includes such combinations.

As used in this specification and the appended claims, the term "if" may be interpreted contextually as "when", "upon" or "in response to a determination" or "in response to a detection". Similarly, the phrase "if it is determined" or "if a [ described condition or event ] is detected" may be interpreted in accordance with the context to mean "upon determining" or "in response to determining" or "upon detecting [ described condition or event ]" or "in response to detecting [ described condition or event ]".

During walking, the ankle joint plays an important role, with the peak values of the joint moment and power being highest compared to the hip and knee joints. Therefore, the old and the patient with muscular atrophy are easy to have insufficient pedaling force when walking. Ankle exoskeletons can help people to enhance walking ability, for example: the exoskeleton can assist the old, the patient with myasthenia, the soldier to walk and the like, can assist the ankle joint of the human body to exert force, and further improves the walking capability of the human body by assisting the ankle joint of the human body to exert force.

In general, the power-assisted control of the ankle exoskeleton is mainly divided into three steps: current gait environment recognition, gait division and power-assisted control. The method comprises the steps of firstly determining the current gait environment of a user through a foot inertia measurement unit or a visual identification mode, then dividing the current gait, and finally giving different power-assisted curves for different gait environments.

However, this is a relatively clear tandem control method, and in the sensing-prediction-assistive process, errors in any one of the environment recognition and gait segmentation links may cause erroneous assistive force in the assistive control link, and the accuracy of the currently adopted technology is relatively low, for example, in the environment recognition process, visual recognition is usually adopted, and the recognition rate is affected by various factors such as illumination, so that the assistive reliability is relatively low.

Based on the ankle exoskeleton and the power assisting control method, device and readable storage medium thereof, the power assisting value can be determined without depending on mode recognition such as visual recognition, and the reliability of ankle power assisting is improved.

In order to explain the technical scheme of the invention, the following description is made by specific embodiments with reference to the accompanying drawings.

Fig. 1 is a schematic diagram illustrating an implementation flow of a power-assisted control method for an ankle exoskeleton according to an embodiment of the present invention. The power-assisted control method for the ankle exoskeleton can be applied to the ankle exoskeleton and can be executed by a control device (a driving box) in the ankle exoskeleton, and specifically comprises the following steps 101 to 105.

Step 101: acquiring left leg angle data and right leg angle data of a user, and determining a left leg angle difference and a right leg angle difference of the user;

the user left leg angle data is an angle between a left leg and a hip joint (gravity direction) of the user, the right leg angle data is an angle between a right leg and the hip joint (gravity direction) of the user, and the user left and right leg angle difference is a difference value between the angle between the left leg and the hip joint (gravity direction) of the user and the angle between the right leg and the hip joint (gravity direction).

It should be noted that the left leg angle data and the right leg angle data are vector data. For example, with the gravity direction as the position of the angle scale 0, the counterclockwise angle scale sign is positive, and the clockwise angle scale sign is negative, then the user's left leg is forward and right leg is rearward as shown on the left in FIG. 2In the case of (2), the left leg angle data is (+ θ) _l -0), right leg angle data is (- θ) _r -0), i.e. left leg angle data of + θ _l Angle data of right leg is-theta _r Therefore, the left-right leg angle difference obtained by subtracting the right leg angle data from the left leg angle data is + θ _l -(-θ _r ) To obtain theta _l +θ _r 。

For clarity of illustration, a schematic diagram of left leg angle data and right leg angle data is shown in fig. 2, where the left is the situation where the user's left leg is in front of the right leg and the right is the situation where the user's left leg is in front of the back right leg.

The angle scale of the direction of the gravity is determined to be 0, and the numerical values of the angles between the left leg and the gravity direction and the numerical values of the angles between the right leg and the gravity direction are respectively theta in the case that the left leg of the user is in front of the right leg of the user and the angle between the right leg of the user and the gravity direction are in back _l And theta _r And the left leg angle data is q _l ＝+θ _l The right leg angle data is q _r ＝-θ _r The left leg angle data minus the right leg angle data has a left-right leg angle difference of theta _l +θ _r (ii) a In the case that the user's right leg is in front of the left leg and behind the left leg, the angle values of the user's left and right legs with respect to the gravity direction are respectively theta _l And theta _r And the left leg angle data is q _l ＝-θ _l The right leg angle data is q _r ＝+θ _r The left and right leg angle difference obtained by subtracting the right leg angle data from the left leg angle data is- (theta) _l +θ _r )。

The biomechanical observation of walking shows that in the case of flat ground, ascending slope, descending slope and ascending stair, the time deviation value between the maximum value moment of the angle difference between the left leg and the right leg (the difference between the angle value between the left leg and the hip joint and the angle value between the right leg and the hip joint) and the moment of the maximum moment value of the force exerted by the ankle joint is close to a fixed value in one gait cycle, so that the assistance value required by the user can be determined based on the time deviation relationship between the angle difference between the left leg and the right leg of the user and the moment in the walking process of the user.

It should be noted that, for the ankle exoskeleton left leg power assisting part, the left and right leg angle difference is obtained by subtracting the right leg angle data from the left leg angle data, and for the ankle exoskeleton right leg power assisting part, the left and right leg angle difference is obtained by subtracting the left leg angle data from the right leg angle data.

In practical applications, for a user who only has one leg and needs assistance, the ankle exoskeleton may be only used for assisting the left leg of the user, or only used for assisting the right leg of the user, and for a user who needs assistance for both legs, the ankle exoskeleton may assist both the left leg and the right leg of the user.

Correspondingly, when the ankle exoskeleton is only used for assisting the left leg of the user, the left-right leg angle difference is obtained by subtracting the right leg angle data from the left leg angle data, and when the ankle exoskeleton is only used for assisting the right leg of the user, the left-right leg angle difference is obtained by subtracting the left leg angle data from the right leg angle data.

When the ankle exoskeleton not only assists the left leg of a user but also assists the right leg of the user, the left-right leg angle difference obtained by subtracting the right leg angle data from the left leg angle data and the left-right leg angle difference obtained by subtracting the left leg angle data from the right leg angle data need to be calculated at the same time.

For example, optionally, the ankle exoskeleton may comprise: angle measuring device, drive box, bowden cable and foot dress subassembly.

As shown in fig. 3, for the structural schematic diagram of the ankle exoskeleton provided in the embodiment of the present invention, the angle measuring device may be an inertia measuring unit 601 located on the left leg and the right leg of the user, and configured to collect left leg angle data and right leg angle data of the user, the driving box 602 is configured to determine a power assistance value based on the left leg angle data and the right leg angle data, and drive and control a bowden cable 603 on the left leg and the right leg to move based on the power assistance value, and the bowden cable drives the foot step wearing assembly to move to provide power assistance.

Alternatively, as shown in fig. 3, the foot worn assembly may include a fixed rigid frame 6041 and a rotating rigid frame 6042.

Wherein the fixed rigid frame can be fixed on the shoe through the fixing component 605, and the rotating rigid frame can be fixed on the lower leg of the user through the fixing component 605.

Alternatively, the fixing component may be a shoe bandage, or may be an adhesive fixing material, which is not limited in the present invention.

In practical application, the driving box 601 can drive the bowden cable 603 to pull the fixed rigid frame 6041 fixed on the shoe by using the motor, the fixed rigid frame 6041 and the rotating rigid frame 6042 fixed on the shank rotate relatively to drive the foot ankle joint of the user to perform plantarflexion movement, so as to provide assistance for the plantarflexion movement of the foot ankle joint of the user when the user walks, so as to assist the foot plantarflexion of the user to step on the ground, thereby reducing energy consumption of the user when the user walks and reducing moment output of the foot ankle joint of the user.

Optionally, the ankle exoskeleton may further comprise a tension sensor for measuring a tension value on the bowden cable to feed back to the driving box, and the driving box provides assistance according to the tension value and the assistance value.

Optionally, the angle measuring device may be an angle measuring sensor mounted on a hip joint of a human body, or a stretchable sensor attached to a garment.

Step 102: and determining the gait moment corresponding to the left and right leg angle difference based on the corresponding relation between the left and right leg angle difference and the time of the previous step state period of the user.

Specifically, a time deviation exists between the moment of the maximum value of the angle difference and the moment of the maximum moment value of the force exerted by the ankle joint, and the time deviation is close to a certain value in proportion to the length of the gait cycle in which the angle difference exists, so that the gait moment of the user in one gait cycle needs to be determined according to the current angle difference of the user, and the time deviation is carried out subsequently.

Typically, a gait cycle can be the process of landing a certain foot (e.g., the left foot) until the foot (left foot) again lands. Thus, optionally, the moment when a certain foot (e.g., the left foot) lands on the ground can be used as the beginning of a gait cycle, and the moment when the foot (e.g., the left foot) lands on the ground again can be used as the end of the gait cycle and as the beginning of the next gait cycle.

It should be noted that the previous gait cycle is a previous gait cycle immediately adjacent to the current gait of the user, so the gait condition of the previous gait cycle is the same as or similar to the gait condition of the current user.

The corresponding relation between the angle difference of the left leg and the right leg of the previous gait cycle of the user and the time is the angle difference condition of the previous gait cycle of the user, and the corresponding relation corresponds to the angle difference data of the left leg and the right leg of the user at each moment in the previous gait cycle.

It should be noted that the corresponding relationship between the left-right leg angle difference of the previous user step period and the time may refer to the corresponding relationship between the left-right leg angle difference obtained by subtracting the right leg angle data from the left leg angle data of the previous user step period and the time, or refer to the corresponding relationship between the left-right leg angle difference obtained by subtracting the left leg angle data from the right leg angle data of the previous user step period and the time, specifically, when it is determined in step 101 that the left-right leg angle difference of the user is the first difference value obtained by subtracting the right leg angle data from the left leg angle data, the corresponding relationship between the left-right leg angle difference of the previous user step period and the time at least includes the corresponding relationship between the left-leg angle difference obtained by subtracting the right leg angle data from the left leg angle data of the previous user step period and the time, when it is determined in step 101 that the left-right leg angle difference of the user is the second difference value obtained by subtracting the left leg angle data from the right leg angle data, the corresponding relationship between the left-right leg angle difference and the time of the previous step state period of the user at least comprises the corresponding relationship between the left leg angle difference and the time obtained by subtracting the left leg angle data from the right leg angle data of the previous step state period of the user.

In the specific application, because the gait condition difference between two adjacent gait cycles of the user is small, even if the user moves at a variable speed, the change between the two adjacent gait cycles is small, therefore, the gait time corresponding to the left-right leg angle difference is determined based on the corresponding relation between the left-right leg angle difference and the time of the previous gait cycle of the user, so that the reference of the gait cycle is more accurate, even if the gait environment (such as flat ground) of the user at the early stage is different from the gait environment (such as sloping ground) of the user at the later stage, the obtained gait cycle can be closest to the current gait condition of the user, the reliability of the judgment of the assistance value is improved, the assistance control method can be suitable for variable speed and multiple terrains, and the exoskeleton can be used for outdoor complex conditions.

Step 103: acquiring gait assistance delay time of a current gait cycle of a user;

the gait assistance delay time corresponds to a gait cycle and is used for carrying out time migration on the gait moment of the user in the gait cycle in which the current angle difference value is located.

Optionally, in some embodiments of the present invention, the gait-assisted delay time of the current gait cycle of the user may be obtained by obtaining a preset gait cycle-assisted delay ratio and a current gait cycle duration estimated value of the user, and multiplying the preset gait cycle-assisted delay ratio and the current gait cycle duration estimated value of the user.

The preset gait cycle power-assisted delay proportion can be adjusted according to the size of a user.

The user current gait cycle estimated value is an estimated value of the length of a gait cycle corresponding to the user current gait. Specifically, the cycle duration of the immediately previous step state cycle may be obtained as the estimated value of the current gait cycle of the user.

In a specific application, because the gait condition difference between two adjacent gait cycles of the user is small, even if the user moves at a variable speed, the change between the two adjacent gait cycles is small, and therefore, the cycle duration of the immediately previous gait cycle can be obtained to be used as the current gait cycle estimated value of the user.

Step 104: determining a power-assisted left-right leg angle difference corresponding to the left-right leg angle difference based on the gait time and the gait power-assisted delay time corresponding to the left-right leg angle difference in the corresponding relation between the left-right leg angle difference and the time;

and the angle difference of the left and right leg of the assistance corresponding to the angle difference of the left and right leg is the angle difference which is obtained after time offset and is used for directly determining the assistance value and corresponds to the current moment.

Specifically, in some embodiments of the present invention, the assisting force left-right leg angle difference corresponding to the left-right leg angle difference may be determined through the following steps 201 to 202.

Step 201: determining a power-assisted angle difference moment based on a gait moment and a gait power-assisted delay time corresponding to the angle difference of the left leg and the right leg;

step 202: in the correspondence relationship between the left-right leg angle difference and time, the left-right leg angle difference corresponding to the assist angle difference time is determined as the assist left-right leg angle difference corresponding to the left-right leg angle difference.

For example, illustratively, as shown at 41-44 in FIG. 4, the left and right leg angle difference is obtained by subtracting the right leg angle data from the left leg angle data, and the current left and right leg angle difference y is used _l () Determining a power-assisted left and right leg angle difference y _l Schematic procedure of (T + α T). Wherein, the angle difference in the figure is the angle difference of the left leg and the right leg.

41: acquiring the corresponding relation between the previous step state cycle angle difference and the time of the user (corresponding to the corresponding relation between the angle difference obtained by subtracting the right leg angle data from the left leg angle data and the time), and the current left-right leg angle difference y of the user _l (t)；

42: determining the position of the current angle difference data in the corresponding relation between the previous step state cycle angle difference and the time of the user;

43: determining the gait moment t corresponding to the angle difference according to the position of the current angle difference data in the corresponding relation between the angle difference and the time in the last gait cycle ₁ Then, acquiring gait assistance delay time alpha T of the current gait cycle of the user (wherein alpha is a preset gait cycle assistance delay proportion, T is a user current gait cycle time length estimated value, and the cycle time of the previous step state cycle can be used as the current gait cycle time length estimated value), and further acquiring gait assistance delay time alpha T corresponding to the gait assistance delay time alpha T and the angle difference according to the gait time T ₁ For gait time t ₁ Shifting to determine gait time as t ₁ +αT；

44: determining t in the corresponding relation between the previous step state period angle difference and the time ₁ + α T momentThe corresponding angle difference value is the angle difference y of the left leg and the right leg of the assisting force corresponding to the current angle difference _l (t ₁ + α T), i.e. y _l (t+αT)。

It should be noted that, in the above example, the left and right leg angle difference is the process of determining the left and right leg angle difference of the assistance force when the left leg angle data is subtracted from the right leg angle data, and accordingly, the subsequently determined assistance force value is the assistance force value corresponding to the left leg portion of the ankle joint exoskeleton. Moreover, for the left and right leg angle difference data obtained by subtracting the left leg angle data from the right leg angle data, the corresponding relationship between the previous gait cycle angle difference and the time of the user corresponding to the left leg angle difference data (corresponding to the corresponding relationship between the angle difference obtained by subtracting the left leg angle data from the right leg angle data and the time) and the corresponding relationship between the previous gait cycle angle difference and the time under the condition of subtracting the left leg angle difference data from the left leg angle data are symmetrical about the x coordinate axis, and the corresponding process for determining the power-assisted left and right leg angle difference corresponding to the left and right leg angle difference is the same as the process, so the process is not repeated.

Step 105: and calculating a power assisting value corresponding to the ankle exoskeleton based on the power assisting left and right leg angle difference, and controlling the ankle exoskeleton to provide power assisting based on the power assisting value.

Specifically, in some embodiments of the present invention, the assist value corresponding to the ankle exoskeleton can be obtained by obtaining a preset assist gain coefficient and multiplying the preset assist gain coefficient by the assist left-right leg angle difference.

For example, the current assist right and left leg angle difference is

(in FIG. 4, y is _l (T + alpha T)), the gain coefficient is k, and the corresponding assistance value of the ankle exoskeleton is

(corresponding to FIG. 4, the force values for the left leg segment in the ankle exoskeleton are denoted by k x y _l (t+αT)。)

The assistance value corresponding to the ankle exoskeleton may be an assistance value of a left leg portion in the ankle exoskeleton or an assistance value of a right leg portion in the ankle exoskeleton, depending on the left-right leg angle difference of the user determined in step 101. For example, if the left-right leg angle difference of the user determined in step 101 is a difference (a first difference) obtained by subtracting the right leg angle data from the left leg angle data, the assistance value corresponding to the ankle exoskeleton is the assistance value of the left leg portion in the ankle exoskeleton; if the left-right leg angle difference of the user determined in step 101 is a difference (second difference) obtained by subtracting the left leg angle data from the right leg angle data, the assistance value corresponding to the ankle exoskeleton is the assistance value of the right leg portion of the ankle exoskeleton.

The preset boosting gain coefficient can be adjusted by a user to meet boosting requirements of different users.

It should be noted that, because the ankle exoskeleton is used for providing assistance, if the assistance value corresponding to the ankle exoskeleton is calculated based on the angle difference between the left leg and the right leg of assistance and is a negative value, the ankle exoskeleton is controlled to provide assistance based on the assistance value, which means that the ankle exoskeleton provides assistance of 0, that is, no assistance is provided.

In the embodiment of the invention, the use environment of a user (different use environments and different angle difference data of the user) is indirectly reflected through the angle difference data of the user without gait environment identification by acquiring the left leg angle data and the right leg angle data of the user, determining the gait time corresponding to the left leg angle difference and the right leg angle difference based on the corresponding relation of the left leg angle difference and the right leg angle difference of the previous step state period of the user and acquiring the gait assistance delay time of the current gait period of the user, further determining the assistance left leg angle difference and the right leg angle difference corresponding to the left leg angle difference based on the gait time and the corresponding relation of the left leg angle difference and the right leg angle difference and the time, calculating the assistance value corresponding to the ankle joint exoskeleton based on the assistance left leg angle difference and the right leg angle difference and further controlling the ankle joint exoskeleton to provide assistance based on the assistance value, the current gait condition of the user is determined based on the corresponding relation between the angle difference of the left leg and the right leg of the previous step state period of the user and the time, and then the exoskeleton assistance value is calculated based on the angle difference data of the user, so that the determination of the assistance value only depends on the angle difference data and does not depend on mode identification such as visual identification, and the reliability of the ankle joint assistance is improved.

Through biomechanical observation of walking, the maximum value of the angle difference value is much larger than that of the angle difference value when going downstairs when going on flat ground, uphill, downhill and upstairs.

As shown in fig. 5, in the embodiment of the present invention, before the step 105 calculates a power assisting value corresponding to the ankle exoskeleton based on the angle difference between the left leg and the right leg for assisting, and controls the ankle exoskeleton to provide assisting power based on the power assisting value, the following steps are further included.

Step 301: judging whether the angle difference of the left leg and the right leg is greater than a preset angle difference threshold value or not;

according to biological analysis, the value of the preset angle difference threshold is 20-30, and the value can be adjusted according to different users.

Step 302: if the angle difference of the left leg and the right leg is smaller than or equal to a preset angle difference threshold value, determining that the corresponding force-assisting value of the ankle joint exoskeleton is 0;

correspondingly, in the embodiment of the present invention, the step 105 of calculating the assistance value corresponding to the ankle exoskeleton based on the assistance left and right leg angle difference, and controlling the ankle exoskeleton to provide assistance based on the assistance value specifically includes:

step 303: if the angle difference of the left leg and the right leg is larger than the preset angle difference threshold value, acquiring a preset assistance gain coefficient, subtracting the angle difference of the left leg and the right leg with assistance from the preset angle difference threshold value to obtain a third difference value, multiplying the preset assistance gain coefficient by the third difference value to obtain an assistance value corresponding to the ankle exoskeleton, and controlling the ankle exoskeleton to provide assistance based on the assistance value.

In the embodiment of the invention, if the angle difference of the left leg and the right leg of the user is smaller than or equal to the preset angle difference threshold, the current angle difference of the left leg and the right leg of the user is smaller, and the force required by the ankle joint of the corresponding user is smaller, so that the force value corresponding to the ankle joint exoskeleton is determined to be 0; if the angle difference of the left leg and the right leg of the user is larger than the preset angle difference threshold, it is indicated that the ankle joint of the user needs larger force, therefore, the preset angle difference threshold is subtracted from the angle difference of the left leg and the right leg of the assistance, the obtained difference value is multiplied by the preset assistance gain coefficient, the product is determined as the assistance value corresponding to the ankle joint exoskeleton, and the ankle joint exoskeleton is controlled to provide assistance for the user based on the assistance value.

For example, the difference y between the right and left leg angles is determined _l (t) if it is greater than a predetermined angular difference threshold ε, if y _l (t)<E, determining the assistance value corresponding to the ankle exoskeleton to be 0 (in the example corresponding to fig. 3, determining the assistance value corresponding to the left leg part of the ankle exoskeleton to be 0); if y _l (t)>E, the corresponding angle difference y of the left leg and the right leg of the assisting force _l Subtracting the preset angle difference threshold value from the (T + alpha T) to obtain y _l (T + α T) - ε, and then multiplying the sum by a predetermined boost gain k to obtain the corresponding force value of the ankle exoskeleton (in the example corresponding to FIG. 3, the force value of the left leg of the ankle exoskeleton) as kX (y) _l (t+αT)-ε)。

It should be noted that, when the angle difference between the left leg and the right leg is greater than the preset angle difference threshold, in the process of determining the assistance value, a difference obtained by subtracting the preset angle difference threshold from the angle difference between the left leg and the right leg is possibly less than 0, and therefore, after multiplying the difference by the preset gain coefficient k, the obtained assistance value is still a negative value.

In the embodiment of the invention, through the preset angle difference threshold value, when the angle difference threshold value of the left leg and the right leg of the user is not more than the preset angle difference threshold value, the gait environment of the current user does not need to be assisted (for example, go down stairs), therefore, the assistance value corresponding to the ankle joint exoskeleton is 0, when the angle difference threshold value of the left leg and the right leg of the user is more than the preset angle difference threshold value, the current gait environment of the user needs to be assisted (for example, flat ground, go up and down slopes, go up stairs and the like), the assistance left leg and the right leg angle difference corresponding to the angle difference of the left leg and the right leg are further subtracted from the preset angle difference threshold value, so that the assistance value corresponding to the ankle joint exoskeleton is obtained, and different assistance is carried out on different ecological environments in a mode of setting up the threshold value, so that the assistance control of the exoskeleton can adapt to different indoor and outdoor environments.

It should be noted that the above-mentioned power assisting control method described in steps 101 to 105 describes a process of determining the power assisting value according to the angle difference data of the user at the current time. In practice, the power-assisted control method can be obtained according to the following formula:

taking the assistance of the left leg part of the exoskeleton of the ankle joint as an example:

wherein, F _l The power curve of the left leg of the ankle exoskeleton (i.e. the corresponding relationship between the power value of the left leg of the ankle exoskeleton and time), y _l And (T) the corresponding relation (for example, a left-right leg angle difference curve) between the left-right leg angle difference obtained by subtracting the right leg angle data from the user left leg angle data and the time, wherein epsilon is a preset angle difference threshold value, k is a preset power-assisted gain coefficient, alpha is a preset gait cycle power-assisted delay proportion, and T is a current gait cycle time length estimated value.

Similarly, the power assistance of the right leg part of the ankle exoskeleton is as follows:

wherein, F _r For the power curve of the left leg part of the ankle joint exoskeleton (namely the corresponding relation between the power value of the right leg part of the ankle joint exoskeleton and time), y _r (t) is the corresponding relation between the left and right leg angle difference obtained by subtracting the left leg angle data from the right leg angle data of the user and the time (for example, the left and right leg angle difference curve), and the rest parameters have the same meaning with the left leg part, and are not longer the same hereThe description is given in detail.

As can be seen from the above formula, when the corresponding relationship between the angle difference between the left and right legs of the user and the time (for example, the angle difference curve between the left and right legs of the user) is known, and when the angle difference between the left and right legs of the user is greater than the preset angle difference threshold, the angle difference curve between the left and right legs may be translated and expanded, so as to obtain the power curve of the user (i.e., the corresponding relationship between the power value and the time).

For example, as shown in fig. 6A, the correspondence relationship between the left-right leg angle difference obtained by subtracting the right leg angle data from the left leg angle data in two adjacent gait cycles and time (left leg angle difference curve in the figure) is an imaginary line portion in the figure, in which the lower half of the curve is a portion in which the angle difference is smaller than 0. According to the above formula, a corresponding power curve when the angle difference between the left leg and the right leg of the user is greater than the preset angle difference threshold value, that is, a left leg power curve shown by a solid line part in the figure, can be obtained.

Accordingly, as shown in fig. 6B, the correspondence relationship between the left-right leg angle difference obtained by subtracting the left leg angle data from the right leg angle data in two adjacent gait cycles and time (the right leg angle difference curve in the figure) is a portion shown by a broken line in the figure, wherein the lower half of the curve is a portion where the angle difference is smaller than 0. According to the above formula, a power assisting curve corresponding to the case that the angle difference between the left leg and the right leg of the user is larger than the preset angle difference threshold value, namely, a right leg power assisting curve shown by the solid line part in the figure can be obtained.

The left leg assistance curve and the right leg assistance curve in the two adjacent gait cycles are superimposed to obtain the assistance curve of the ankle exoskeleton when the angle difference between the left leg and the right leg of the user in the two adjacent gait cycles is larger than the preset angle difference threshold value as shown in fig. 6C, wherein for the purpose of distinguishing, the dotted curve part is the left leg assistance curve, and the solid curve part is the right leg assistance curve. It can be seen that during one gait cycle the ankle exoskeleton applies alternating assistances to the left and right legs and that there is a period of 0 assistances due to the angular difference threshold set.

In some embodiments of the present invention, the user left leg angle data and the user right leg angle data in the above step 101 may be obtained by measurement of inertial measurement units IMU worn on the user's left and right legs, as described in particular in steps 401 to 403 below.

Step 401: obtaining angle measurement data of an IMU on a left leg and angle measurement data of an IMU on a right leg of a user;

the angle measurement data of the IMU on the left leg of the user is angle data of the left leg of the user, and the angle measurement data of the IMU on the right leg of the user is angle data of the right leg of the user.

Step 402: acquiring IMU wearing deviation values of a left leg and a right leg of a user;

the wearing deviation values of the IMUs of the left leg and the right leg represent the wearing symmetry condition of the IMUs of the left leg and the right leg of the user, namely under an ideal condition, the IMUs of the left leg and the right leg of the user are symmetrically worn, and the wearing deviation values of the IMUs of the left leg and the right leg are close to 0 or equal.

It should be noted that the IMU wearing deviation value of the left leg and the right leg of the user is generated according to the IMU wearing condition of the user, that is, each time the user wears the ankle exoskeleton and wears the IMU device, the IMU wearing deviation value may exist, and for the secondary user wearing the ankle exoskeleton and using the same, the IMU wearing deviation value is fixed in the using process after wearing the IMU device, so that the IMU wearing deviation value can be determined when the user just wears the ankle exoskeleton.

Specifically, after the exoskeleton is powered on, a user can step symmetrically left and right (generally 2 to 3 steps are needed, and the steps can be set according to a program), so that a revision value is determined based on the stepping condition. Wherein a symmetrical step is advantageous for obtaining the revised value accurately.

Specifically, because the IMU is located on the user's thigh strap, the user is binding up when dressing the IMU, can inevitably lead to two legs about can dressing the back, and the gesture of two IMUs is distinguished for the thigh gesture. That is, in general, the postures of the two thighs of the user are symmetrical, for example, it appears that the maximum value obtained by subtracting the angle difference of the right leg from the angle difference of the left leg is consistent with the minimum value (negative value) in amplitude, but if the IMU device is not worn properly, when the IMU measurement data is used as the corresponding angle data of the left leg and the right leg, the maximum value obtained by subtracting the angle difference of the right leg from the angle difference of the left leg may be inconsistent with the minimum value (negative value) in amplitude, and if the IMU measurement data is not revised, the IMU measurement data is directly calculated as the thigh angle, which may cause the power assistance of the left leg and the right leg to be greatly different, and thus the comfort of the user may be reduced. Therefore, a wear revision of the IMU data is required.

In some embodiments of the present invention, IMU wear bias values for the user's left and right legs may be determined through steps 501-504 described below.

Step 501: obtaining left leg angle measurement data θ of an IMU on a user's left leg for one or more gait cycles _l (t) and right leg Angle measurement data θ of the IMU on the Right leg _r (t)；

Step 502: determining the difference g between the left leg angle measurement data and the right leg angle measurement data _l (t)＝θ _l (t)- θ _r (t) and the difference g between the right leg angle measurement data and the left leg angle measurement data _r (t)＝θ _r (t)-θ _l (t)；

Step 503: difference g between left leg angle measurement data and right leg angle measurement data _l () Extracting N preset measurement data points as left leg and right leg angle difference measurement data points, and calculating the average value M of the N left leg and right leg angle difference measurement data points _l And the difference g between the right leg angle measurement data and the left leg angle measurement data _r (t) extracting N preset value measurement data points as right leg and left leg angle difference measurement data points, and calculating the average value M of the N right leg and left leg angle difference measurement data points _r ；

In particular, the method comprises the following steps of,

if the left leg IMU and the right leg IMU are both worn properlyThen g is _l The positive and negative peaks of (t) coincide, and thus, for g _l (t) discretizing, wherein when N measurement data points are extracted, the average value of the N data points is close to 0; in the same way, because g _l (t) and g _r (t) is symmetric about the x-axis coordinate (Cartesian coordinate system), for g if both left and right leg IMUs are worn correctly _r (t) discretizing, wherein when N measurement data points are extracted, the average value of the N data points is close to 0. Therefore, it is possible to determine M _l (M _r ) And the relationship between the first threshold and the second threshold, the revised value of wear is determined, as described in step 504 below.

Step 504:

if the average value M of the N left leg and right leg angle difference measurement data points _l If the value is larger than the first threshold value, determining the IMU wearing deviation value delta of the left leg _l ＝-M _l IMU wearing deviation value delta of right leg _r ＝0；

If the average value M of the N left leg and right leg angle difference measurement data points _l If the value is less than the second threshold value, determining the IMU wearing deviation value delta of the left leg _l 0, deviation value delta of IMU wearing of right leg _r ＝-M _r ；

If the average value M of the N left leg and right leg angle difference measurement data points _l Greater than or equal to the second threshold value and less than or equal to the first threshold value, an IMU wear deviation value δ for the left leg is determined _l 0, deviation value delta of IMU wearing of right leg _r 0; wherein the first threshold is greater than the second threshold.

The first threshold and the second threshold may be determined according to practical experience.

Alternatively, both the first threshold and the second threshold may be determined to be 0.

Optionally, the first threshold and the second threshold may be close to 0, that is, the first threshold is greater than 0 and close to 0 (e.g., 0.01), and the second threshold is less than 0 and close to 0 (e.g., -0.01).

Specifically, when the first threshold is 0.01 and the second threshold is-0.01, if M is _l Greater than a first threshold (e.g., M) _l 0.1), it is inferred that the measurement data of the left leg is large, and therefore, the deviation value δ is worn by the IMU of the left leg _l ＝-M _l IMU wearing deviation value delta of right leg _r Is 0; if M is _l Less than a second threshold (e.g., M) _l -0.1), it can be inferred that the measurement data of the right leg is large, and therefore, the IMU wear deviation value δ of the left leg is made _l 0, IMU wearing deviation value delta of right leg _r ＝-M _r (ii) a If M is _l Greater than or equal to the second threshold value, and less than or equal to the second threshold value (e.g., M) _l 0), g can be deduced _l And (t) the positive amplitude value and the negative amplitude value are close to each other, the IMU is worn properly at the moment, and the wearing deviation value is set to be 0.

Step 403: and determining the left leg angle data and the right leg angle data of the user according to the angle measurement data of the IMU on the left leg and the angle measurement data of the IMU on the right leg of the user and the IMU wearing deviation value.

Specifically, the left leg angle data of the user may be determined as q _l (t)＝θ _l (t)+δ _l The right leg angle data of the user may be determined as q _r (t)＝θ _r (t)+δ _r 。

In the embodiment of the invention, the inertial measurement unit IMU is adopted to obtain the angle data of the left leg and the right leg, so that the assistance value is calculated, and the inertial measurement unit IMU does not contain a mode identification part and has high reliability; because the IMU has the wearing deviation problem, the IMU measurement data is corrected and then determined as the angle data of the left leg and the right leg, and the problem that the left leg and the right leg have large power-assisted deviation due to wearing is avoided.

It should also be noted that, for simplicity of description, the above-mentioned method embodiments are described as a series of action combinations, but those skilled in the art will recognize that the present invention is not limited by the described action sequences, and some steps may be performed in other sequences in some embodiments of the present invention.

Fig. 7 shows a schematic structural diagram of an assistance control device 700 for an ankle exoskeleton, which includes a first obtaining unit 701, a first determining unit 702, a second obtaining unit 703, a second determining unit 704, and a control unit 705.

A first obtaining unit 701, configured to obtain left leg angle data and right leg angle data of a user, and determine a left-right leg angle difference of the user;

a first determining unit 702, configured to determine a gait time corresponding to the left-right leg angle difference based on a correspondence between the left-right leg angle difference and the time in the previous step period of the user;

a second obtaining unit 703, configured to obtain a gait assistance delay time of a current gait cycle of the user;

a second determining unit 704, configured to determine, based on the gait time and the gait assistance delay time corresponding to the left-right leg angle difference, an assistance left-right leg angle difference corresponding to the left-right leg angle difference in the correspondence between the left-right leg angle difference and the time;

the control unit 705 is configured to calculate a power assisting value corresponding to the ankle exoskeleton based on the power assisting left and right leg angle difference, and control the ankle exoskeleton to provide power assistance based on the power assisting value.

It should be noted that, for convenience and brevity of description, the specific working process of the ankle exoskeleton power control device 700 described above may refer to the corresponding process of the method described in fig. 1 to 5, and will not be described again here.

The ankle exoskeleton comprises a driving box, an angle measuring device, a Bowden cable and a foot wearing component, wherein the angle measuring device is used for collecting left leg angle data and right leg angle data of a user, and the driving box is used for realizing steps in an embodiment of the power control method of the ankle exoskeleton so as to control the Bowden cable in the ankle exoskeleton to drive the foot wearing component to move to provide power assistance.

As shown in fig. 8, the above-described drive cassette includes: a processor 80, a memory 81, and a computer program 82, such as an ankle exoskeleton's power assist control program, stored in the memory 81 and executable on the processor 80. The processor 80, when executing the computer program 82, implements the steps in the above-described method embodiment of ankle exoskeleton assistance control, such as the steps 101 to 105 shown in fig. 1. Alternatively, the processor 80, when executing the computer program 82, implements the functions of the modules/units in the device embodiments, for example, the functions of the first acquiring unit 701, the first determining unit 702, the second acquiring unit 703, the second determining unit 704, and the control unit 705 shown in fig. 7.

The computer program 82 may be divided into one or more modules/units, which are stored in the memory 81 and executed by the processor 80 to complete the invention. The one or more modules/units may be a series of computer program instruction segments capable of performing specific functions for describing the execution of the computer program 82 in the ankle exoskeleton 8. For example, the computer program 82 may be divided into a first acquisition unit, a first determination unit, a second acquisition unit, a second determination unit, and a control unit (unit in the virtual device), and the specific functions are as follows:

the first acquisition unit is used for acquiring left leg angle data and right leg angle data of a user and determining the left leg angle difference and the right leg angle difference of the user;

the first determining unit is used for determining gait moments corresponding to the left and right leg angle differences based on the corresponding relation between the left and right leg angle differences and time of the previous step state period of the user;

a second determining unit, configured to determine, based on the gait time and the gait assistance delay time corresponding to the left-right leg angle difference, an assistance left-right leg angle difference corresponding to the left-right leg angle difference in the correspondence between the left-right leg angle difference and the time;

and the control unit is used for calculating a power assisting value corresponding to the ankle exoskeleton based on the power assisting left and right leg angle difference and controlling the ankle exoskeleton to provide power assisting based on the power assisting value.

The power assisting control device for the ankle exoskeleton may include, but is not limited to, a processor 80 and a memory 81. Those skilled in the art will appreciate that fig. 8 is merely an example of an ankle exoskeleton 8, and does not constitute a limitation on ankle exoskeleton 8, and may include more or fewer components than those shown, or some components in combination, or different components, for example, the power assist control apparatus of the ankle exoskeleton may further include an input-output device, a network access device, a bus, etc.

It should be understood that, in the embodiment of the present invention, the Processor 81 may be a Central Processing Unit (CPU), and the Processor may also be other general processors, Digital Signal Processors (DSPs), Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs) or other Programmable logic devices, discrete Gate or transistor logic devices, discrete hardware components, and the like. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

The memory 81 may be an internal storage unit of the ankle exoskeleton 8, such as a hard disk or a memory of the power assist control device of the ankle exoskeleton. The memory 81 may also be an external storage device of the ankle exoskeleton 8, such as a plug-in hard disk, a Smart Media Card (SMC), a Secure Digital (SD) Card, a Flash memory Card (Flash Card), or the like, provided on the ankle exoskeleton 8. Further, the memory 81 may also include both an internal memory unit and an external memory device of the ankle exoskeleton 8. The memory 81 is used to store the computer program and other programs and data required by the ankle exoskeleton 8. The memory 81 may also be used to temporarily store data that has been output or is to be output.

It will be apparent to those skilled in the art that, for convenience and brevity of description, only the above-mentioned functional units and modules are illustrated as being divided, and in practical applications, the above-mentioned functions may be distributed as different functional units and modules according to needs, that is, the internal structure of the apparatus may be divided into different functional units or modules to implement all or part of the above-mentioned functions.

Each functional unit and module in the embodiments may be integrated in one processing unit, or each unit may exist alone physically, or two or more units are integrated in one unit, and the integrated unit may be implemented in a form of hardware, or in a form of software functional unit. In addition, specific names of the functional units and modules are only used for distinguishing one from another, and are not used for limiting the protection scope of the present invention. For the specific working processes of the units and modules in the system, reference may be made to the corresponding processes in the foregoing method embodiments, which are not described herein again.

In the above embodiments, the descriptions of the respective embodiments have respective emphasis, and for parts that are not described or recited in detail in a certain embodiment, reference may be made to the descriptions of other embodiments.

Those of ordinary skill in the art would appreciate that the elements and algorithm steps of the various embodiments described in connection with the embodiments disclosed herein may be implemented as electronic hardware, or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

In the embodiments provided herein, it should be understood that the disclosed apparatus/drive cartridge and method may be implemented in other ways. For example, the above-described device/driver cartridge embodiments are merely illustrative, and for example, the division of the above modules or units is only one logical functional division, and in actual implementation, there may be another division, for example, multiple units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

The integrated modules/units described above, if implemented in the form of software functional units and sold or used as separate products, may be stored in a computer readable storage medium. Based on such understanding, all or part of the flow of the method according to the embodiments of the present invention may be implemented by instructing related hardware through a computer program, where the computer program may be stored in a computer-readable storage medium, and when the computer program is executed by a processor, the computer program may implement the steps of the embodiments of the method. The computer program includes computer program code, and the computer program code may be in a source code form, an object code form, an executable file or some intermediate form. The computer readable medium may include: any entity or device capable of carrying the above-described computer program code, recording medium, U.S. disk, removable hard disk, magnetic diskette, optical disk, computer Memory, Read-Only Memory (ROM), Random Access Memory (RAM), electrical carrier signal, telecommunications signal, and software distribution medium, etc. It should be noted that the computer readable medium described above may include content that is subject to appropriate increase or decrease as required by legislation and patent practice in jurisdictions, for example, in some jurisdictions, computer readable media that does not include electrical carrier signals and telecommunications signals in accordance with legislation and patent practice.

The above-mentioned embodiments are only used for illustrating the technical solutions of the present invention, and not for limiting the same; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the present invention, and are intended to be included within the scope thereof. The spirit and scope of the embodiments should be construed as being encompassed by the present invention.

Claims

1. An assistance control method for an ankle exoskeleton, the assistance control method comprising:

acquiring gait assistance delay time of the current gait cycle of the user;

and calculating a power assisting value corresponding to the ankle joint exoskeleton based on the power assisting left and right leg angle difference, and controlling the ankle joint exoskeleton to provide power assisting based on the power assisting value.

2. The power-assisted control method of claim 1, wherein the obtaining the gait power-assisted delay time of the current gait cycle of the user comprises:

acquiring a preset gait cycle assistance delay proportion and a user current gait cycle duration estimated value;

and multiplying the preset gait cycle assistance delay proportion by the user current gait cycle duration estimated value to obtain the gait assistance delay time of the user current gait cycle.

3. The assist control method according to claim 1, wherein the determining, in the correspondence relationship between the left-right leg angle difference and time, the assist left-right leg angle difference corresponding to the left-right leg angle difference based on the gait time corresponding to the left-right leg angle difference and the gait assist delay time includes:

determining a power-assisted angle difference moment based on the gait moment corresponding to the angle difference between the left leg and the right leg and the gait power-assisted delay time;

and in the corresponding relation between the left leg angle difference and the right leg angle difference and the time, determining the left leg angle difference and the right leg angle difference corresponding to the assistance angle difference as the assistance left leg angle difference and the assistance right leg angle difference corresponding to the left leg angle difference and the right leg angle difference.

4. The power-assisted control method of claim 1, wherein the calculating a corresponding power-assisted value for the ankle exoskeleton based on the power-assisted left-right leg angular difference comprises:

acquiring a preset boosting gain coefficient;

and multiplying the preset power-assisted gain coefficient by the angle difference of the left and right power-assisted legs to obtain a power-assisted value corresponding to the ankle exoskeleton.

5. The assist control method of claim 1 further comprising, prior to the calculating a corresponding assist value for the ankle exoskeleton based on the assisted left and right leg angle difference:

judging whether the angle difference of the left leg and the right leg is greater than a preset angle difference threshold value or not;

if the angle difference between the left leg and the right leg is smaller than or equal to the preset angle difference threshold value, determining that the corresponding force assisting value of the ankle exoskeleton is 0;

the step of calculating a power assisting value corresponding to the ankle joint exoskeleton on the basis of the power assisting left and right leg angle difference, and controlling the ankle joint exoskeleton to provide power assisting on the basis of the power assisting value specifically comprises the following steps:

if the angle difference of the left leg and the right leg is larger than the preset angle difference threshold value, acquiring a preset assistance gain coefficient, subtracting the angle difference of the left leg and the right leg with assistance from the preset angle difference threshold value to obtain a third difference value, multiplying the preset assistance gain coefficient by the third difference value to obtain an assistance value corresponding to the ankle exoskeleton, and controlling the ankle exoskeleton to provide assistance based on the assistance value.

6. An assistive control method according to any one of claims 1-5, wherein inertial measurement units IMUs are worn on the left and right legs of the user, and the obtaining left and right leg angle data of the user comprises:

obtaining angle measurement data of an IMU on a left leg and angle measurement data of an IMU on a right leg of a user;

obtaining IMU wearing deviation values of a left leg and a right leg of a user;

and determining the left leg angle data and the right leg angle data of the user according to the angle measurement data of the IMU on the left leg and the angle measurement data of the IMU on the right leg of the user and the IMU wearing deviation value.

7. An assist control method as set forth in claim 6 wherein the IMU wear offset values for the user's left and right legs are determined according to:

obtaining left leg angle measurement data θ of an IMU on a user's left leg for one or more gait cycles _l (t) and right leg Angle measurement data θ of the IMU on the Right leg _r (t)；

Determining a difference g between the left leg angle measurement data and the right leg angle measurement data _l (t)＝θ _l (t)-θ _r (t) and the difference g between the right leg angle measurement data and the left leg angle measurement data _r (t)＝θ _r (t)-θ _l (t)；

A difference g between the left leg angle measurement data and the right leg angle measurement data _l (t) extracting N preset measurement data points as left leg and right leg angle difference measurement data points, and calculating the mean value M of the N left leg and right leg angle difference measurement data points _l And the difference g between the right leg angle measurement data and the left leg angle measurement data _r (t) extracting N preset measurement data points as right leg and left leg angle difference measurement data points, and calculating the mean value M of the N right leg and left leg angle difference measurement data points _r ；

If the average value M of the N left leg and right leg angle difference measurement data points _l Greater than or equal to the second threshold and less than or equal to the first threshold, determining an IMU wear deviation value δ for the left leg _l 0, deviation value delta of IMU wearing of right leg _r 0; wherein the first threshold is greater than or equal to the second threshold.

8. An ankle exoskeleton power control device, comprising:

the device comprises a first acquisition unit, a second acquisition unit and a third acquisition unit, wherein the first acquisition unit is used for acquiring left leg angle data and right leg angle data of a user and determining a left leg angle difference and a right leg angle difference of the user;

a second determining unit, configured to determine, based on the gait time corresponding to the left-right leg angle difference and the gait assistance delay time, an assistance left-right leg angle difference corresponding to the left-right leg angle difference in the correspondence relationship between the left-right leg angle difference and time;

9. An ankle exoskeleton comprising a drive box, an angle measuring device, a Bowden cable, and a foot-worn assembly, the angle measuring device for collecting left and right leg angle data of a user, the drive box for performing the assistance control method of any one of claims 1 to 7 to control the Bowden cable in the ankle exoskeleton to move the foot-worn assembly to provide assistance.

10. A computer-readable storage medium, in which a computer program is stored, which, when being executed by a processor, implements a power assist control method according to any one of claims 1 to 7.