CN114209541A

CN114209541A - Walking assisting exoskeleton device

Info

Publication number: CN114209541A
Application number: CN202111265094.1A
Authority: CN
Inventors: 王琳; 姜鹏; 王烨; 邵天琪; 李光林
Original assignee: Shenzhen Institute of Advanced Technology of CAS
Current assignee: Shenzhen Institute of Advanced Technology of CAS
Priority date: 2021-10-28
Filing date: 2021-10-28
Publication date: 2022-03-22
Also published as: WO2023070863A1

Abstract

The application discloses a walking assistance exoskeleton device, comprising: the hip joint component comprises a shell, a cam and an elastic part, and the elastic part comprises a first supporting leg and a second supporting leg which are arranged at a set angle; the knee joint subassembly is used for wearing in user's knee joint portion, and the shell is used for wearing in user's hip joint portion to rotatory to first direction at the relative first stabilizer blade of connecting rod drive cam, and make the second stabilizer blade keep away from first stabilizer blade motion along the partial cambered surface of first side, and when the second stabilizer blade is close to first stabilizer blade motion and resets, drive the relative first stabilizer blade of cam and rotate to the second direction relative with first direction, the cam drives the connecting rod and rotates to the second direction. Through the mode, the exoskeleton device can effectively reduce the walking burden of a human body, is light in weight, simple to wear, strong in man-machine cooperativity and capable of coordinating with the gait of the human body.

Description

Walking assisting exoskeleton device

Technical Field

The invention relates to the technical field of mechanical exoskeleton, in particular to a walking assisting exoskeleton device.

Background

In recent years, with the rapid development of mechano-electronic and control technologies, research on exoskeleton rehabilitation robots is further driven. The exoskeleton is different from an orthosis, cannot replace legs of a user to support, provides assistance and assistance for the user when the user walks, and can replace the help of a therapist through long-time repeated relevant exercise training, so that the rehabilitation cost is effectively reduced.

However, the typical exoskeleton systems in the market, such as HAL (hybrid assisted limb) and ReWalk (lower extremity exoskeleton robot), mostly adopt a rigid connection driving design, which has a large weight and a large extra burden during use, and can increase the metabolic consumption of the wearer.

Other exoskeletons used for rehabilitation or to enhance performance of the human body have lacked practical applications. There are still many technical challenges to be solved in developing a portable lower extremity exoskeleton that can be used in practical applications. For example, exoskeletons driven by pneumatic artificial muscle actuators lack portability due to the power source and are not highly accurate in controlling position and force due to the compressibility of air. Therefore, it is not suitable for daily rehabilitation training. Furthermore, it is not energy efficient for the driver to generate the required braking torque during rehabilitation training of the wearer.

Disclosure of Invention

The application provides a walking assistance exoskeleton device, can solve the weight of the exoskeleton system among the prior art great, and extra burden is big during the use, can increase the metabolic consumption of wearer, and is not high to the control accuracy of position and power to be not applicable to daily rehabilitation training, the not energy-conserving problem of the required braking moment of torsion of corresponding driver production.

In order to solve the technical problem, the application adopts a technical scheme that: there is provided a walking assist exoskeleton device, wherein the walking assist exoskeleton device comprises: a knee joint component for wearing on a knee joint portion of a user; one end of the connecting rod is connected to the knee joint component; the hip joint subassembly, which comprises an outer shell, cam and elastic component, the shell is used for wearing in user's hip joint portion, the other end that the knee joint subassembly was kept away from to the cam is connected in shell and connecting rod, the elastic component is including being first stabilizer blade and the second stabilizer blade that sets for the angle setting, first stabilizer blade is connected in the shell, second stabilizer blade butt in the first side of cam, connecting rod drive cam is first stabilizer blade rotatory to the first direction relatively, so that the first stabilizer blade motion is kept away from along the part cambered surface of first side to the second stabilizer blade, and when the second stabilizer blade is close to first stabilizer blade motion and resets, it is rotatory to the second direction relative with the first direction to drive first stabilizer blade of cam, the cam drives the connecting rod and rotates to the second direction.

The elastic piece is a torsion spring mechanism and further comprises a roller, the second supporting leg comprises a first supporting rod and a second supporting rod, one end of the first supporting rod is connected to the first supporting rod, the other end of the first supporting rod is perpendicularly connected to the second supporting rod, and the roller is sleeved on the second supporting rod and abuts against the first side face.

The projection of the part of the cambered surface of the first side surface on the second side surface of the cam meets a set curve function relation; wherein the second side is perpendicular to the first side.

The hip joint component further comprises a transmission piece, one end of the transmission piece is connected to the connecting rod, a first through hole is formed in the second side face of the cam, the other end of the transmission piece penetrates through the first through hole, and the transmission piece is driven by the connecting rod or the cam to rotate so as to assist the connecting rod to drive the cam to rotate or assist the cam to drive the connecting rod to rotate.

Part of the structure of the transmission piece protrudes out of the first through hole to form a protruding part, and the protruding part abuts against the shell; wherein, the radial dimension of bellying is greater than the radial dimension of first through-hole.

The hip joint assembly further comprises a clamp spring, a clamp spring groove is formed in the side face, facing the hole wall of the first through hole, of the transmission piece, and the clamp spring is sleeved in the clamp spring groove to limit the transmission piece to move along the central axis direction of the first through hole.

Wherein, first through-hole includes to being close to the sunken portion that first side concave was established, and the side protrusion of the pore wall of driving medium towards first through-hole is formed with flat key portion, and flat key portion inlays and locates the sunken portion to the restriction driving medium is relative cam rotary motion.

The hip joint assembly further comprises a connecting rod fixing shell, the connecting rod fixing shell is buckled on one side face, far away from the shell, of the transmission part, and the other end of the connecting rod is connected between the transmission part and the connecting rod fixing shell so as to be matched and fixed with each other through the transmission part and the connecting rod fixing shell.

And a second through hole is formed on the second side surface of the cam, is in a crescent shape and is arranged at an interval with the first through hole.

Wherein the set angle is 85-95 degrees, and the change range of the included angle of the first supporting leg relative to the second supporting leg during operation is 85-135 degrees.

The beneficial effect of this application is: unlike the prior art, the present application provides a walking assist exoskeleton device comprising: the hip joint component further comprises a shell, a cam and an elastic part, the elastic part comprises a first supporting leg and a second supporting leg which are arranged at a set angle, one end of the connecting rod is connected to the knee joint component, the cam is connected to the shell and the other end of the connecting rod, which is far away from the knee joint component, the first supporting leg is connected to the shell, the second supporting leg is abutted to a first side face of the cam, and the connecting rod drives the cam to rotate towards a first direction relative to the first supporting leg; wherein, the knee joint subassembly is used for wearing at user's knee joint portion, the shell is used for wearing at user's hip joint portion, in order to be rotatory to the first direction at the relative first stabilizer blade of connecting rod drive cam, and make the second stabilizer blade when the part cambered surface of first side is kept away from first stabilizer blade motion, carry out the elasticity energy storage, in order to be close to when first stabilizer blade motion resets at the second stabilizer blade, it is rotatory to the second direction relative with the first direction to drive the relative first stabilizer blade of cam, and then it is rotatory to the second direction to drive the connecting rod through the cam, thereby can avoid using extra power device to provide the helping hand, and direct negative work stage at human walking in-process carries out the energy storage, and feed back to the human body, in order to reach the purpose of assisting human walking. Therefore, the walking assisting exoskeleton device can help patients with walking dysfunction to recover natural gait by wearing the walking assisting exoskeleton device, so that the walking capability is improved, the motor function rehabilitation is realized, and the independent life quality is enhanced; compared with the conventional gait auxiliary equipment, the walking auxiliary exoskeleton device can naturally acquire the walking energy of the human body, and further can feed back the walking energy to the human body through the exoskeleton device for assisting walking so as to reduce the walking burden of the human body; and because no extra power device is needed, the corresponding weight is light, the wearing is simple, the man-machine cooperativity is strong, and the human gait can be coordinated.

Drawings

FIG. 1 is a schematic diagram of an exploded view of an embodiment of a walking assist exoskeleton device of the present application;

FIG. 2 is an exploded view of the hip joint assembly of the walking assist exoskeleton device of FIG. 1;

FIG. 3 is a schematic diagram of a simplified 2D walking model;

FIG. 4 is a detailed schematic view of the resilient member of the hip joint assembly of FIG. 2;

FIG. 5 is a detailed schematic view of the cam in the hip joint assembly of FIG. 2;

FIG. 6 is a schematic view of a cord-wound cam system;

FIG. 7 is a schematic illustration of a cam profile fitting curve;

figure 8 is a detailed schematic view of the transmission in the hip joint assembly of figure 2.

Detailed Description

The inventor finds that walking is the basic requirement of daily life of human beings through long-term research, and walking dysfunction seriously affects the quality of life of individuals. In our daily lives, there are too many factors that can lead to walking dysfunction, and most people experience some form of walking dysfunction throughout their lives. With the progress of aging of the population in China, serious social problems and economic problems caused by the loss of mobility are not small. There is therefore an urgent need to develop a feasible solution for walking aid to assist and improve the mobility of the patient, thereby improving the quality of life. Wearable gait aids are an effective way to address this increasingly serious problem.

Over the past decades, with advances in technology, researchers have developed new gait assistance devices to replicate the patient's daily activities. Among them, the Knee Ankle Foot Orthosis Knee Ankle Foot Orthopis (KAFO) has been widely used for the treatment of lower limb fractures, arthritis, patients after joint surgery, and corrective treatment of abnormal gait. KAFO is used to provide stability to the knee and ankle joints while indirectly affecting the stability of the hip joint through ground reaction forces. By limiting knee and ankle motion, gait of the wearer produces unnatural motions, such as raising the hips to compensate, passively increasing metabolic costs of the wearer. When wearing KAFO, gait typically has the disadvantages of high metabolic cost, slow walking speed, low comfort for wearing for a long time, and the like, compared to normal gait. In addition, patients often require the intervention and assistance of a physical therapist during the course of rehabilitation therapy.

According to different exoskeleton action modes, the exoskeleton can be divided into two main categories: active exoskeletons and passive exoskeletons. In the active gait assistance exoskeleton, the driving modes include motor driving, hydraulic driving, pneumatic driving, artificial muscle driving and the like, wherein the active exoskeleton mainly adopts a motor as a driving mode. The motor is driven relatively flexibly, and can be matched with a speed reducer, a clutch, a connecting rod mechanism and the like to transmit joints.

Specifically, the HAL exoskeleton robot for lower limb rehabilitation is commercialized, and mainly comprises a wireless LAN (Local Area Network) system, an electric driving system, a sensing system, an executing mechanism and the like, wherein the robot comprises power supply modules on two sides of lower limbs and a waist, the mass of the power supply modules is 23 kg, the weight of the power supply modules is 15 kg, and the power supply modules have 26 degrees of freedom.

The Rewalk lower limb exoskeleton robot comprises lower limbs on two sides and a backpack, and a power module and a control system are integrated in the backpack. Rewalk can help patients with paralyzed lower limbs to stand, walk, turn and go upstairs and downstairs.

The exoskeleton robot for lower limb rehabilitation has gradually developed towards commercialization as an intelligent bionic auxiliary rehabilitation device. Experimental results have confirmed that the exoskeleton can help patients with walking dysfunction to perform rehabilitation treatment, and improve the athletic ability of the human body for healthy people during normal walking, weight-bearing walking and even running.

However, the exoskeleton systems currently on the market, such as the HAL and ReWalk, are designed to be rigidly connected. Although quick accurate position and angle control can be realized, weight is great, and extra burden is big during the use, can increase the metabolism consumption of wearer, and simultaneously, rigid mechanism can cause certain restriction to the degree of freedom of motion of joint, and length and walking efficiency are long in the restriction use.

Other exoskeletons used for rehabilitation or to enhance performance of the human body have lacked practical applications. The development of a portable lower extremity exoskeleton that can be used in practical applications still requires a number of technical challenges to be addressed. For example, an exoskeleton driven by a pneumatic artificial muscle driver lacks portability due to a power source, and the control accuracy of position and force is not high due to the compressibility of air. Therefore, it is not suitable for daily rehabilitation training. Furthermore, it is not energy efficient for the driver to generate the required braking torque during rehabilitation training of the wearer.

Therefore, through the biomechanical analysis of the lower limbs, based on the walking dysfunction patient with certain mobility, a passive gait rehabilitation device which is simple and portable and is coordinated with the human body is urgently needed to be designed, so that the passive gait rehabilitation device has the characteristics of joint movement restriction reduction, light weight, convenience and quickness in wearing and the like.

In order to effectively reduce the burden of walking of a human body, light in weight, simple to wear, strong in man-machine cooperativity and capable of being coordinated with the gait of the human body, the application provides a walking assisting exoskeleton device. The present application will be described in further detail with reference to the following drawings and examples. It is to be noted that the following examples are only illustrative of the present application, and do not limit the scope of the present application. Likewise, the following examples are only some examples and not all examples of the present application, and all other examples obtained by a person of ordinary skill in the art without any inventive work are within the scope of the present application.

Reference in the specification to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the specification. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein can be combined with other embodiments.

Referring to fig. 1-2, fig. 1 is a schematic diagram of an exploded configuration of an embodiment of a walking assist exoskeleton device of the present application, and fig. 2 is a schematic diagram of an exploded configuration of a hip joint assembly in the walking assist exoskeleton device of fig. 1. In the present embodiment, the walking assistance exoskeleton device 1 includes: knee joint component 10, connecting rod 20, and hip joint component 30.

The walking assisting exoskeleton device 1 provided in the present application can be specifically used for assisting a person in walking, for example, by wearing the walking assisting exoskeleton device 1, a walking dysfunction patient can recover natural gait, the walking ability of the walking dysfunction patient can be improved, and motor function rehabilitation can be realized, so that the independent life quality of the walking assistance exoskeleton device can be enhanced. And is particularly suitable for hemiplegic patients with certain mobility, elderly people with weak legs and feet and difficulty in walking, people with walking inconvenience caused by accidental injury, or sports enthusiasts such as long-time hiking and mountain climbing. Of course, in other embodiments, the walking assisting exoskeleton device 1 can also be used in joints of an intelligent robot or any other reasonable mechanical device, which is not limited by the embodiment.

Specifically, the knee joint component 10 is adapted to be worn on the knee joint of the user, and one end of the connecting rod 20 is connected to the knee joint component 10, the hip joint component 30 further comprises a housing 31, a cam 33 and an elastic member 32, and the housing 31 is adapted to be worn on the hip joint of the user, and the cam 33 is connected to the housing 31 and the other end of the connecting rod 20 away from the knee joint component 10.

It will be understood that the walking assistance exoskeleton device 1 can assist the walking of a human body by wearing the knee joint component 10 and the hip joint component 30 on the knee joint part and the hip joint of the human body respectively and realizing the connection and the force transmission between the knee joint component 10 and the hip joint component 30 through the connecting rod 20.

Further, the elastic element 32 of the hip joint assembly 30 specifically includes a first leg 321 and a second leg 322, the first leg 321 and the second leg 322 are disposed at a set angle in an initial state, and an included angle between the first leg 321 and the second leg 322 can be gradually increased under the action of a corresponding external force, and can be restored by springing back when the external force disappears.

Specifically, the first leg 321 is connected to the housing 31, and the second leg 322 abuts against the first side 331 of the cam 33, so that when the connecting rod 20 drives the cam 33 to rotate relative to the first leg 321 in a first direction, for example, when a person wearing the walking-assisted exoskeleton device 1 swings in a direction opposite to the walking direction of the person wearing the walking-assisted exoskeleton device 1, the knee joint assembly 10 can drive the cam 33 of the hip joint assembly 30 to rotate relative to the first leg 321 in the first direction through the connecting rod 20, and the second leg 322 moves away from the first leg 321 along a part of the arc surface of the first side 331 of the cam 33, that is, the included angle between the second leg 322 and the first leg 321 gradually increases under the external force, so as to store energy.

When the human body drives the walking assisting exoskeleton device 1 to swing towards the walking direction, that is, to walk forwards, the external force driving the cam 33 to rotate towards the first direction relative to the first leg 321 disappears, and at this time, the elastic member 32 of the hip joint assembly 30 will rebound to reset, that is, the included angle between the second leg 322 and the first leg 321 will return to the initial state, the second leg 322 will move to reset close to the first leg 321 to drive the cam 33 to rotate towards the second direction relative to the first leg 321, and the cam 33 will drive the connecting rod 20 to rotate towards the second direction, so as to provide an assisting force for the movement of the human body towards the current walking direction, for example, to provide an upward lifting force and a forward swinging force for the human body.

The first side 331 of the cam 33 is perpendicular to the second side 332 thereof, and the extending direction of the connecting rod 20 is parallel to the second side 332. And the first side surface 331 specifically refers to an outer peripheral surface of the cam 33, i.e., an annular curved surface.

The first direction may specifically correspond to a direction opposite to a current walking direction of the human body, and the second direction corresponds to the current walking direction of the human body.

Note that, as shown in fig. 3, fig. 3 is a schematic diagram of a simplified 2D walking model. The 2D walking model can specifically correspond to a knee-joint-free two-dimensional passive robot model, the robot has no driving and control system, the mechanism is simple, and only one degree of freedom of a hip joint is provided, so that the actual walking scene of a human body can be simulated. Therefore, when the initial conditions of the robot, such as the initial joint angle (the swing angle in fig. 3) and the initial joint angular velocity, are properly adjusted to match the passive dynamics and the environmental parameters (the slope angle) of the robot, the robot can be ensured to stably walk on a slope with a certain slope. In the pure passive walking process, each gait cycle is similar to the swinging process of an inverted pendulum, and the continuous walking is formed by connecting a plurality of inverted pendulum swinging cycles. The energy consumption during walking is mainly generated by the impact between the foot and the ground in the connection transition process between two adjacent gait cycles, namely the supporting leg and the ground in fig. 3, and the energy supplement is completely provided by the gravity, namely the gravity when the swinging leg positioned above the ground swings towards the walking direction. Through the experiment on the robot, the stability problem and the energy problem of passive walking can be correspondingly analyzed, so that the influence of the mechanism parameters of the robot on the walking performance can be obtained.

It can be understood that the walking assisting exoskeleton device 1 can be worn on the lower limbs of one side of the corresponding human body, or worn on the lower limbs of the two sides of the human body, respectively, so that during the walking process of the human body, the walking assisting exoskeleton device 1 can store energy when the human body swings to the opposite direction of the walking direction, and release energy when the human body walks forwards, so as to provide a pulling force and a forward swinging force for the lower limbs of the human body, thereby assisting the human body to walk.

In the above-mentioned scheme, the walking assisting exoskeleton device 1 can perform elastic energy storage by driving the cam 33 to rotate towards the first direction relative to the first leg 321 through the connecting rod 20, so that when the second leg 322 moves away from the first leg 321 along a part of the arc surface of the first side surface 331, so as to drive the cam 33 to rotate towards the second direction relative to the first leg 321 when the second leg 322 moves and resets close to the first leg 321, and further drive the connecting rod 20 to rotate towards the second direction through the cam 33, so that the walking assisting exoskeleton device 1 can avoid using an additional power device to provide assistance, and directly perform energy storage at a negative work stage in a human body walking process, and feed back to the human body, so as to achieve the purpose of assisting the human body to walk. Therefore, the walking assisting exoskeleton device 1 can help a walking dysfunction patient to recover natural gait by wearing, so that the walking capability is improved, the motor function rehabilitation is realized, and the independent life quality is enhanced; compared with the conventional gait assistance equipment, the walking assistance exoskeleton device 1 can naturally acquire the walking energy of the human body, and further can feed back the walking energy to the human body through the exoskeleton device for assisting walking, so that the walking burden of the human body is reduced; and because no extra power device is needed, the corresponding weight is light, the wearing is simple, the man-machine cooperativity is strong, and the human gait can be coordinated.

With continuing reference to fig. 4-5, fig. 4 is a detailed structural view of the resilient member of the hip joint assembly of fig. 2, and fig. 5 is a detailed structural view of the cam of the hip joint assembly of fig. 2.

In an embodiment, the elastic element 32 is specifically a torsion spring mechanism, and the elastic element 32 further includes a roller 323, the second supporting leg 322 includes a first supporting rod 3221 and a second supporting rod 3222, one end of the first supporting rod 3221 is connected to the first supporting rod 321, the other end of the first supporting rod 3221 is vertically connected to the second supporting rod 3222, and the roller 323 is sleeved on the second supporting rod 3222 and abuts against the first lateral surface 331.

The torsion spring mechanism is a device in which one end is fixed and the other end is applied with a torque. Under the action of torque, the torsion spring mechanism can be twisted and deformed, and the size of the deformation angle of the torsion spring mechanism has a certain relation with the torque. The simplest is, for example, a torsion spring, which is elastically deformed by bending under the action of a torque, so that the spring generates a torque in a plane. The torsion spring is often used for energy storage, torque transmission and compression.

Optionally, the roller 323 is in any reasonable shape and form that facilitates sliding, such as a cylinder, an elliptic cylinder, or a sphere, and a through hole arranged in a cylindrical shape is formed in the middle of the roller 323.

In an embodiment, the projection of the partial arc surface of the first side surface 331 of the cam 33 on the second side surface 332 thereof further satisfies a set curve function relationship; wherein the second side surface 332 is perpendicular to the first side surface 331.

Note that, as shown in fig. 6, fig. 6 is a schematic view of a rope winding cam system. Therein, taking as an example the use of a rope-wound spring system based on a cam 33, i.e. cam a in the figure, the system is embodied by a linear spring, a cam 33 and an inelastic wire wound around the cam 33 and connected to the spring to achieve the effect of a simulated torsion spring arrangement. When the cam 33 rotates, the inelastic wire wound around the cam 33 pulls the spring to generate torque, and different torque deformation angle correspondences, namely, F (u) can be obtained by designing different cam 33 profiles and the like_T) And α.

Conversely, we can also satisfy the moment-angle relationship (F (u) by discrete points_T) Corresponding to a) is performed, i.e. the cam a in fig. 6 is designed around a pattern of partial arcs provided with inelastic threads. In this case, it is necessary to perform curve fitting on the discrete moment points. The theoretical value of the discrete moment point is solved based on various parameters of the special-shaped ball torsion spring sample.

Setting torsion spring mechanism working torsion angle (working load lower limit torsion)

Free angle of torsion spring mechanism (clamp between two pins when no load is present)Angle) is 90 deg.. According to the structural space consideration given by the hip joint exoskeleton, the diameter d of a torsion spring is given to be 2mm, and the number n of turns of the torsion spring is given to be 6. The torsion spring material is carbon spring steel wire grade C. And (6) looking up a table to obtain:

ultimate tensile strength σ_b＝1710Mpa；

Allowable bending stress sigma_BP＝0.8σ_b＝0.8*1710＝1368Mpa；

Considering the compact structure, the temporary rotation ratio c is 6;

coefficient of curvature

The diameter D of the torsion spring mechanism is C, D, 6, 2 and 12 mm;

stiffness of torsion spring mechanism

Wherein E is the modulus of elasticity, i.e., an amount of resistance to elastic deformation of the material from which the torsion spring mechanism is made, an indicator of the stiffness of the material;

working limit torque

The following fits discrete moment points, as shown in table 1.

Working angle	Moment (Nmm)
		100°	233.45
110°	466.9
		120°	700.35

Specifically, as shown in fig. 7, fig. 7 is a schematic view of a curve fitted to the profile of the cam 33. By discussing that the continuity of the moment and the moment derivative is a necessary condition for the contour smoothing of the cam 33, the cubic curve is a fitting curve satisfying the condition with the lowest power, and the cubic spline curve is used for fitting the moment curve below.

For N +1(N ≧ 2) discrete torque points, expressed as:

G[α(i)]＝G_i,i＝0,1,...,N；

then curve G may be used_i(α) fitting, wherein G_i(α) satisfies:

G_i(α_i-1)＝G_i-1,G_i(α_i)＝G_i,i＝1,2,...,N；

the curve G_i(α) the corresponding cam 33 profile coordinates can be described as:

(x,y)＝[x_i(α_i),y(α_i)],i＝1,2,...,N；

the cubic spline curve satisfies the following condition:

G(α)＝G_iand (. alpha.) is a cubic polynomial.

G (α), derivative G (α)', second derivative G (α) ", which is always continuous in the interval, i.e. the function is smooth.

Specifying cubic differential distribution of spline curves, i.e.

G”₀(α₁)＝G”₁(α₁)；

G”_N-2(α_N-1)＝G”_N-1(α_N-1)。

Then N cubic polynomial segments are obtained as:

G_i(α)＝a_i+b_i(α-α_i)+c_i(α-α_i)²+d_i(α-α_i)³

wherein, a_i，b_i，c_i，d_iN represents 4N unknown coefficients.

It will be appreciated that in a specific embodiment, the projection of the part of the arc of the first side 331 of the cam 33 on the second side 332 thereof also specifically satisfies the curve function exemplified above and the part of the arc satisfying the curve function corresponds to the part of the arc of the second leg 322 sliding back and forth along the first side 331 of the cam 33 during walking.

With continuing reference to FIG. 8, FIG. 8 is a schematic diagram of a detailed construction of the transmission member of the hip joint assembly of FIG. 2.

In one embodiment, the hip joint assembly 30 further comprises a transmission member 34, one end of the transmission member 34 is connected to the connecting rod 20, and the second side surface 332 of the cam 33 is formed with a first through hole 3301, so that the other end of the transmission member 34 can pass through the first through hole 3301 to be fixedly connected with the cam 33.

Therefore, the connecting rod 20 drives the transmission member 34 to rotate, and then drives the cam 33 to rotate through the transmission member 34, so that the second leg 322 can move away from the first leg 321 along the partial arc surface of the first side surface 331, and elastic energy storage is performed. When the second supporting leg 322 moves and resets near the first supporting leg 321, the cam 33 can be driven to rotate in a second direction opposite to the first direction relative to the first supporting leg 321, and then the driving member 34 can be driven to rotate by the cam 33, so as to drive the connecting rod 20 to rotate by the driving member 34. Wherein the second side 332 is perpendicular to the first side 331.

In an embodiment, a part of the structure of the transmission member 34 protrudes from the first through hole 3301 to form a protruding portion 341, the protruding portion 341 abuts against the housing 31, and a radial dimension of the protruding portion 341 is greater than a radial dimension of the first through hole 3301, so that the cam 33 can be reliably sleeved on the transmission member 34 without directly contacting the housing 31, and the transmission member 34 can be driven to rotate more smoothly.

In an embodiment, the hip joint assembly 30 further includes a clamp spring 35, a clamp spring groove 3401 is formed on a side surface of the transmission member 34 facing the hole wall of the first through hole 3301, and the clamp spring 35 is sleeved in the clamp spring groove 3401 to be able to limit the movement of the transmission member 34 along the central axis direction of the first through hole 3301.

Further, the first through hole 3301 of the cam 33 further includes a concave portion 3303 recessed near the first side surface 331 thereof, and the side surface of the transmission member 34 facing the hole wall of the first through hole 3301 is protruded to form a flat key portion 342, and the flat key portion 342 is embedded in the concave portion 3303, so as to limit the rotation of the transmission member 34 relative to the cam 33, that is, to enable the transmission member 34 to be fixedly connected with the cam 33.

Optionally, the second side 332 of the cam 33 is further formed with a second through hole 3302, and the second through hole 3302 is meniscus-shaped and spaced apart from the first through hole 3301, so as to ensure the center of gravity of the cam 33 is near or coincident with the geometric center thereof as much as possible, and reduce the weight of the cam 33 as much as possible, so as to reduce the wearing burden of the corresponding human body. In other embodiments, the second through hole 3302 may have any other reasonable shape, such as a trapezoid or an ellipse, which is not limited in this application.

Optionally, the set angle between the first leg 321 and the second leg 322 in the initial state is 85-95 °, and the angle at which the first leg 321 runs relative to the second leg 322 varies in the range of 85-135 °.

In one embodiment, the hip joint assembly 30 further comprises a connecting rod fixing shell 36, the connecting rod fixing shell 36 is buckled on one side of the transmission member 34 away from the outer shell 31, and the other end of the connecting rod 20 is connected between the transmission member 34 and the connecting rod fixing shell 36 so as to be fixed by the transmission member 34 and the connecting rod fixing shell 36 in a mutually matched manner.

In a particular embodiment, the hip joint assembly 30 comprises: the device comprises a shell 31, a cam fixing shell piece 37, a cam 33, an elastic piece 32, a roller 323, a clamp spring 35, a transmission piece 34, a connecting rod fixing shell 36 and a bolt 38.

The bolts 38 specifically include four bolts 9-M3 × 8, one bolt 10-M2.5 × 8, and one bolt 11-M4 × 16. And bolts 38 of various sizes are used specifically for connection fixation between corresponding structural members in the hip joint assembly 30.

Further, the hip joint assembly 30 has two connecting rods 20 fixed between the connecting rod fixing shell 36 and the transmission member 34, when a human body gait, the connecting rods 20 swing along with the thigh, the connecting rods 20 drive the transmission member 34, the rotating cam 33 is axially fixed with the transmission member 34 through the shoulder, a clamp spring groove 3401 is left on the transmission member 34, and when one side of the cam 33 is axially contacted with the transmission member 34, the other side is axially fixed through the clamp spring 35. Meanwhile, a flat key portion 342 is formed on the transmission member 34, so that the transmission member 34 can be circumferentially and rotationally fixed with the cam 33.

The motion principle of the elastic member 32, for example, the torsion spring mechanism and the cam 33 in cooperation in gait is specifically: when the sole of the swing side contacts the ground, the roller 323 on the torsion spring mechanism contacts the cam 33, at this time, the leg on one side of the walking assisting exoskeleton device 1 is put into a supporting state, the thigh swings in the opposite direction of the movement direction, the connecting rod 20 drives the transmission part 34 to rotate, the diameter of the contact point of the cam 33 and the roller 323 is continuously increased, the roller 323 further drives the corresponding pin of the torsion spring mechanism to twist, the torsion spring mechanism generates torque, and the torsion spring mechanism generates maximum working torque at the end stage of the supporting state.

When the swing state is entered, the thigh swings towards the same direction of the motion direction, the connecting rod 20 drives the transmission piece 34 to rotate, the diameter of the contact point of the cam 33 and the roller 323 is continuously reduced, the torque stored by the torsion spring mechanism in the support state is released along with the gait entering the swing state, the released torque drives the cam 33 to rotate, the connecting rod 20 is driven to swing through the transmission piece 34 and the connecting rod fixing shell 36, the connecting rod 20 is connected with the knee joint component 10, and the swing of the knee joint component 10 drives the corresponding knee joint of the human body to swing out towards the walking direction.

It will be appreciated that the torsion spring mechanism cam 33 may be space saving and relatively lightweight to fit in a compact, complex assembly environment. The hip joint assembly 30 functions to absorb the energy of negative work done by the knee joint in gait and provide a forward pulling force on the knee joint during the swing phase.

According to the scheme, when the legs of the human body are loaded, the oxygen consumption of the human body is remarkably increased, the existing gait assistance equipment is developed towards the direction of light weight, and the walking assistance exoskeleton device 1 is suitable for hemiplegic patients with certain mobility, elderly people with weak legs and feet and difficulty in walking, walking inconveniences caused by accidental injuries, or sports enthusiasts such as long-time hiking and mountain climbing. For the crowd, the walking assisting exoskeleton device 1 can effectively coordinate with the human gait direction, is more comfortable to wear than an orthosis, and simultaneously has portability and light weight.

And the gait data and the plantar pressure data of the testee are obtained by performing a three-dimensional motion capture experiment after the product prototype is manufactured, and the data are subjected to kinematics and dynamics analysis. Experimental data prove that the walking assistance exoskeleton device 1 has an improvement effect in assisting gait. The subjective wearing sensation is that a forward lifting effect is provided at the knee joint during gait.

The above embodiments are merely examples and are not intended to limit the scope of the present disclosure, and all modifications, equivalents, and flow charts using the contents of the specification and drawings of the present disclosure or those directly or indirectly applied to other related technical fields are intended to be included in the scope of the present disclosure.

Claims

1. A walking assist exoskeleton device, comprising:

a knee joint component for wearing on a knee joint portion of a user;

a connecting rod, one end of which is connected to the knee joint component;

a hip joint assembly comprising a housing, a cam and a resilient member, the housing being adapted to be worn over a hip joint of a user, the cam is connected to the shell and the other end of the connecting rod away from the knee joint component, the elastic part comprises a first supporting leg and a second supporting leg which are arranged at a set angle, the first supporting leg is connected with the shell, the second supporting leg is abutted against the first side surface of the cam, the connecting rod drives the cam to rotate towards a first direction relative to the first supporting leg, such that the second leg moves away from the first leg along a portion of the arc of the first side, and when the second supporting leg moves and resets close to the first supporting leg, the cam is driven to rotate relative to the first supporting leg in a second direction opposite to the first direction, and the cam drives the connecting rod to rotate in the second direction.

2. The walking assist exoskeleton device of claim 1,

the elastic component is a torsion spring mechanism, the elastic component further comprises a roller, the second support leg comprises a first support rod and a second support rod, one end of the first support rod is connected with the first support leg, the other end of the first support rod is vertically connected with the second support rod, and the roller is sleeved on the second support rod and is abutted to the first side face.

3. The walking assist exoskeleton device of claim 1,

the projection of the partial cambered surface of the first side surface on the second side surface of the cam meets a set curve function relationship; wherein the second side is perpendicular to the first side.

4. The walking assist exoskeleton device of claim 1,

5. The walking assist exoskeleton device of claim 4,

part of the structure of the transmission piece protrudes out of the first through hole to form a protruding part, and the protruding part abuts against the shell; wherein a radial dimension of the boss is greater than a radial dimension of the first through hole.

6. The walking assist exoskeleton device of claim 5,

7. The walking assist exoskeleton device of claim 4,

the first through hole comprises a concave part which is concavely arranged close to the first side surface, the side surface of the transmission piece facing to the hole wall of the first through hole is convexly provided with a flat key part, and the flat key part is embedded in the concave part so as to limit the transmission piece to rotate relative to the cam.

8. The walking assist exoskeleton device of claim 4,

the hip joint component further comprises a connecting rod fixing shell, the connecting rod fixing shell is buckled on one side face, far away from the shell, of the transmission piece, and the other end of the connecting rod is connected between the transmission piece and the connecting rod fixing shell so as to be matched and fixed with the transmission piece and the connecting rod fixing shell.

9. The walking assist exoskeleton device of any one of claims 4 to 8,

the second side surface of the cam is also provided with a second through hole which is in a crescent shape and is arranged at an interval with the first through hole.

10. The walking assist exoskeleton device of any one of claims 1 to 8,

the set angle is 85-95 degrees, and the change range of the included angle of the first supporting leg relative to the second supporting leg during operation is 85-135 degrees.