CN114845680A

CN114845680A - Walking assisting exoskeleton device

Info

Publication number: CN114845680A
Application number: CN202180006242.XA
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: 2022-08-02
Also published as: WO2023070466A1

Abstract

The application discloses a walking assistance exoskeleton device, comprising: the hip joint assembly comprises a first shell, a toothed ring, a straight tooth and a tension spring; wherein, hip joint subassembly, first casing and shank subassembly are used for wearing respectively in user's hip joint portion, knee joint portion and shank portion, and when first casing drove the ring gear and rotates to first direction, the ring gear drives straight tooth and rotates to first direction, and the straight-tooth drives the extension spring and follows its extending direction tensile motion, and when the extension spring kick-backs and resets, the extension spring drives straight tooth and rotates to the second direction relative with first direction, and the straight-tooth drives the ring gear and rotates to the second direction, and the ring gear drives first casing and rotates to the second direction. In this way, the exoskeleton device can assist a human body to walk, is light in weight, simple to wear and strong in man-machine synergy, and can effectively improve the motion capability 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 drive 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 hip joint assembly for wearing on a hip joint portion of a user; one end of the first connecting rod is connected with the hip joint component; the knee joint component comprises a first shell, a gear ring, a straight tooth and a tension spring, wherein the first shell is connected to the other end of the first connecting rod and used for being worn at the knee joint part of a user; when the tension spring rebounds and resets, the tension spring drives the straight tooth to rotate towards a second direction opposite to the first direction, the straight tooth drives the gear ring to rotate towards the second direction, and the gear ring drives the first shell to rotate towards the second direction; one end of the second connecting rod is connected to the first shell; and the lower leg assembly is connected with the other end of the second connecting rod and is worn on the lower leg of the user.

The inner diameter of the toothed ring is twice of the outer diameter of the straight tooth, when the tension spring is in an initial state, a connecting point of the tension spring and the straight tooth is the circle center position of the toothed ring, and the extending direction of the tension spring is perpendicular to a connecting line of the connecting point and the circle center of the straight tooth.

The knee joint component further comprises a first connecting piece and a second connecting piece, the first connecting piece is connected to one side face of the toothed ring, the second connecting piece is connected to one side face of the straight tooth and close to the top point of the outer ring of the straight tooth corresponding to the second connecting piece, and two opposite ends of the tension spring are connected to the first connecting piece and the second connecting piece respectively.

The first shell comprises a connecting rod fixing piece and a first connecting rod clamping plate, the connecting rod fixing piece is connected to the first shell, and the first connecting rod clamping plate is connected to the connecting rod fixing piece and mutually matched with the connecting rod fixing piece to fixedly connect the first connecting rod.

The first shell further comprises a rotary fixing shell, a rotary shell and a sliding piece, the rotary fixing shell is connected to the connecting rod fixing piece, a sliding rail is formed on one side face, facing the rotary shell, of the rotary fixing shell, the rotary shell is connected to the gear ring, one end of the sliding piece is connected to the rotary shell, and the other end of the sliding piece is connected to the sliding rail in a sliding mode.

Wherein, first casing still includes second connecting rod splint, and second connecting rod splint are connected in rotatory shell to mutually support with rotatory shell, with the fixed connection second connecting rod.

The hip joint component comprises a second shell, a cam and an elastic part, wherein the second shell is connected to one end of the first connecting rod and used for being worn at a hip joint part of a user, the cam is connected to the shell and the other end, far away from the knee joint component, of the connecting rod, 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 to the shell, and the second supporting leg abuts against a first side face of the cam; when the first connecting rod drives the cam to rotate towards the first direction, the cam drives the second supporting leg to move away from the first supporting leg along the partial cambered surface of the first side surface, and when the second supporting leg rebounds and resets close to the first supporting leg, the second supporting leg drives the cam to rotate towards the second direction relative to the first supporting leg, and the cam drives the first connecting rod to rotate towards 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 assembly further comprises a transmission piece, one end of the transmission piece is connected to the first 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 to rotate by the first connecting rod or the cam 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 second shell, of the transmission piece, and the other end of the first connecting rod is connected between the transmission piece and the connecting rod fixing shell so as to be mutually matched and fixed by the transmission piece 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 assembly, the first connecting rod, the knee joint assembly, the second connecting rod and the hip joint assembly, wherein the knee joint assembly further comprises a first shell, a toothed ring, a straight tooth and a tension spring, and the hip joint assembly, the first shell and the shank assembly are respectively worn at a hip joint part, a knee joint part and a shank part of a user; wherein, the ring gear is connected in first casing, the straight-tooth meshing is in the inner ring of ring gear, the relative both ends of extension spring are connected respectively in ring gear and straight-tooth, and the extending direction of extension spring passes through the centre of a circle of ring gear, when driving the ring gear to rotate to first direction at first casing, the ring gear can drive the straight-tooth and rotate to first direction, drive extension spring along its extending direction tensile motion through the straight-tooth, and elasticity energy storage, thereby can be when extension spring resilience resets, drive the second direction rotation that the straight-tooth is relative with first direction by the extension spring, the straight-tooth drives the ring gear and rotates to the second direction, the ring gear drives first casing and rotates to the second direction, thereby can avoid using extra power device to provide the helping hand, and direct work load accumulation in the in-process stage of human walking, and feed back to the human body, in order to reach the purpose of supplementary human walking. Therefore, the walking assisting exoskeleton device can help patients with walking dysfunction, such as patients with knee damage, recover natural gait, improve walking ability, realize motor function rehabilitation and enhance independent life quality by wearing the walking assisting exoskeleton device; 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 first shell of the knee joint assembly of FIG. 1;

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

FIG. 4 is a schematic representation of a model of the lower extremity-exoskeleton system of a human;

FIG. 5 is a detailed structural schematic view of the rotating stationary housing in the first housing of FIG. 2;

FIG. 6 is a detailed structural view of the ring gear, spur, first coupling member, and second coupling member of the knee joint assembly of FIG. 1;

FIG. 7 is a schematic structural view of a universal gear mechanism;

FIG. 8 is a schematic structural view of the inverted universal gear mechanism;

FIG. 9 is an exploded view of the hip joint assembly of the walking assist exoskeleton device of FIG. 1;

FIG. 10 is a detailed schematic view of the resilient member of the hip joint assembly of FIG. 9;

FIG. 11 is a detailed schematic view of the cam in the hip joint assembly of FIG. 9;

FIG. 12 is a schematic view of a cord-wound cam system;

FIG. 13 is a schematic illustration of a cam profile fitting curve;

FIG. 14 is a detail of the drive member of the hip joint assembly of FIG. 9;

FIG. 15 is a schematic view of the knee angle as a function of gait cycle;

FIG. 16 is a schematic representation of knee joint angular velocity as a function of gait cycle;

figure 17 shows the angle of the knee joint of the left leg as a function of gait cycle.

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 discovered 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 drivers mainly include a motor (electric transducer), a Series Elastic driver (SEA), a pneumatic artificial muscle pam (pneumatic artificial muscles), and a magnetorheological driver (Regenerative magnetic Actuator). The driving modes comprise motor driving, hydraulic driving, pneumatic driving, artificial muscle driving and the like, wherein the active exoskeleton mainly adopts the motor as the driving mode. The motor is driven relatively flexibly, and can be matched with a speed reducer, a clutch, a link mechanism and the like to transmit joints.

For example, there is a knee exoskeleton driven by a rotary tandem elastic actuator (SEA) for gait assistance. The rotary SEA consists of a dc motor, a worm gear set, a spur gear set and a torsion spring. It is capable of producing continuous peak torque of about 10.86Nm, regardless of gear efficiency. A knee exoskeleton is used for gait assistance, and is specifically composed of a thigh link and a shank link which are driven by a Pneumatic Artificial Muscle (PAM), wherein the PAM comprises flexors and extensors. A knee exoskeleton is used for gait rehabilitation of patients with knee joint dysfunction, and is driven by a reproducible magneto-rheological actuator (Regenerative magneto-rheological actuator), so that the knee exoskeleton has good controllability and high energy efficiency.

HAL lower limb rehabilitation exoskeleton robot is commercialized, and mainly comprises a wireless LAN (Local Area Network) system, an electric driving system, a sensing system, an actuating mechanism and the like, wherein the robot comprises lower limb bilateral and waist power supply modules, the mass of the robot is 23 kg, the lower limb is 15 kg, and the total degree of freedom is 26.

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.

While knee exoskeletons used for rehabilitation or to enhance performance of the human body still lack practical applications, there are still many technical challenges to be solved in developing a portable knee exoskeleton that can be used for practical applications. For example, a knee exoskeleton driven by a pneumatic artificial muscle driver lacks portability due to a power source, and position and force control accuracy is not high due to compressibility of air. Therefore, it is not suitable for daily rehabilitation training. In addition, active exoskeletons are typically heavy, which can cause discomfort to the wearer and increase the metabolic cost of the wearer.

The knee joint is an important ring of the lower limb joint, is a relatively large load bearing joint and has the effect of bearing up and down. For the rehabilitation treatment of patients with knee joint injury, the rehabilitation treatment can not be limited to the assistance of a single knee joint, and the gait of the patients is considered from the angle of the whole lower limb movement by the exoskeleton, so that the rehabilitation effect is achieved.

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 an exploded view of an embodiment of the walking assist exoskeleton device of the present application, and fig. 2 is an exploded view of a first shell of the knee joint assembly of fig. 1. In the present embodiment, the walking assistance exoskeleton device 1 includes: a hip joint component 10, a first connecting rod 20, a knee joint component 30, a second connecting rod 40, and a lower leg component 50.

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 30 further includes a first shell 31, the hip joint component 10 is configured to be worn on the hip joint of the user, opposite ends of the first connecting rod 20 are connected to the hip joint component 10 and the first shell 31, respectively, and the first shell 31 is configured to be worn on the knee joint of the user, and opposite ends of the second connecting rod 40 are connected to the first shell 31 and the lower leg component 50, respectively, and the lower leg component 50 is configured to be worn on the lower leg of the user.

As described above, the hip joint unit 10, the first shell 31, and the lower leg unit 50 are respectively worn on the hip joint portion, the knee joint portion, and the lower leg portion of the user, and the connection between the adjacent units and the transmission of force are performed by the first link 20 and the second link 40, whereby the walking of the user can be effectively assisted.

Further, the knee joint component 30 further comprises a gear ring 32, a straight tooth 33 and a tension spring 34, wherein the gear ring 32 is specifically connected to the first housing 31, and the straight tooth 33 is engaged with the gear ring 32 from a gear tooth facing the center of the circle on the inner ring of the gear ring 32. Opposite ends of the tension spring 34 are respectively connected to specific positions of the toothed ring 32 and the straight teeth 33, and specifically, the extension direction of the tension spring 34 can pass through the center of the toothed ring 32.

When the first shell 31 drives the gear ring 32 to rotate in the first direction, for example, when the user wears the walking assisting exoskeleton device 1 to walk, the energy of ankle joint expansion, i.e. straightening the foot, and calf swing when the tiptoe is far away from the body is absorbed, the calf assembly 50 drives the second connecting rod 40 to transmit in the first direction, and then drives the first shell 31 to rotate in the first direction through the second connecting rod 40, so that the first shell 31 drives the gear ring 32 to rotate in the first direction, and further the straight teeth 33 rotate in the first direction under the action between the gear ring 32 and the teeth of the straight teeth 33. At this time, however, the straight teeth 33 will drive the tension spring 34 to perform stretching motion along the extending direction thereof, that is, to perform linear motion along a certain inner diameter of the toothed ring 32 for energy storage, so that after the tension spring 34 loses force, that is, when a user is ready to lift a foot, the tension spring 34 will rebound to reset and release energy, and further drive the straight teeth 33 to rotate in a second direction opposite to the first direction, the straight teeth 33 drive the toothed ring 32 to rotate in the second direction, and the toothed ring 32 drives the first housing 31 to rotate in the second direction, and further feed back to the second connecting rod 40, so as to compensate for the force required by the dorsal extension of the calf assembly 50, that is, the hooking of a foot, and the swinging of the toe when the toe is close to the body.

It can be understood that the first direction may specifically correspond to the rotation direction of the second connecting rod 40 when the corresponding shank portion of the human body swings to the direction opposite to the current walking direction, and the second direction corresponds to the rotation direction of the second connecting rod 40 when the shank portion of the human body swings to the current walking direction, that is, the knee joint assembly 30 can store energy when the shank of the user supports the ground and the body tilts forward, and release energy when the shank swings to the walking direction, that is, when the shank swings dynamically, and push forward to perform the power-assisted compensation when the shank swings forward, so as to avoid the occurrence of falling caused by insufficient swing of the shank.

Therefore, 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 in 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.

It should be noted that the tension spring 34 is specifically an extension spring, which is also called a tension spring specifically a coil spring that receives axial tension, and the extension spring is generally made of a material with a circular cross section, and when the tension spring is not receiving load, the coils of the extension spring are generally parallel and have no gap. In other embodiments, the tension spring 34 may also be one of other elastic materials with axial tension, which is not limited in this application.

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.

Further, referring to fig. 4, fig. 4 is a schematic diagram of a human lower limb-exoskeleton system model. The exoskeleton consists of a single-degree-of-freedom hip joint exoskeleton, a single-degree-of-freedom knee joint exoskeleton and a shank fixing piece, and gravity compensation is respectively carried out on thighs and shanks during gait.

In this model, the lower limb is simplified to a two-bar linkage representing the thigh and the calf,foot is approximately a mass point m of the end of the lower leg ₃ The handle passes through the hip joint O ₁ The surface S of the human body is defined as a zero potential energy surface, and the gravitational potential energy of the lower limbs and the exoskeleton of the human body under the system can be obtained as follows:

E _G ＝E _Gt +E _Gs +E _Gf ；

wherein E is _Gt 、E _Gs 、E _Gf Representing the gravitational potential energy of the thigh, the calf and the foot, respectively.

E _Gf ＝-m ₃ g[l ₂ cos(θ ₂ -θ ₁ )+l ₁ cosθ ₁ ]；

Wherein m is _i And i is 1,2, 3 respectively representing a human body i _th Mass of (c), m _aj J 1 and 2 respectively represent the external skeleton j in the lower limb-exoskeleton system of the human body _th Mass of (a) < l > _j Represents j _th Length of the connecting rod l _j ^* And s _j Represents the distance from the center of mass of the lower limbs and the exoskeleton of the human body to the joint, theta ₁ ，θ ₂ The rotation angles of the hip joint and the knee joint are shown, respectively.

Based on the above principle, when the first shell 31 drives the toothed ring 32 to rotate in the first direction, the toothed ring 32 can drive the straight teeth 33 to rotate in the first direction, so as to drive the tension spring 34 to do stretching movement along the extending direction through the straight teeth 33, and the elastic energy storage is performed, so that when the tension spring 34 rebounds and resets, the tension spring 34 drives the straight teeth 33 to rotate in the second direction opposite to the first direction, the straight teeth 33 drive the toothed ring 32 to rotate in the second direction, and the toothed ring 32 drives the first shell 31 to rotate in the second direction, so as to avoid using an additional power device to provide assistance, and directly perform energy storage in the negative working stage in the process of human body walking, 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 patients with walking dysfunction, such as patients with knee damage, to recover natural gait, improve walking ability, realize motor function rehabilitation and enhance independent life quality; 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.

In an embodiment, the first housing 31 further includes a connecting rod fixing part 311 and a first connecting rod clamping plate 312, the connecting rod fixing part 311 is connected to the first housing 31, and the first connecting rod clamping plate 312 is connected to the connecting rod fixing part 311 to be capable of cooperating with the connecting rod fixing part 311, so that the first housing 31 is fixedly connected to the first connecting rod 20, and thus can be driven by the first connecting rod 20 to rotate in the same direction, or drive the first connecting rod 20 to rotate in the same direction.

Referring to fig. 5, fig. 5 is a detailed structural diagram of the rotating stationary shell in the first housing of fig. 2.

In one embodiment, the first housing 31 further includes a rotation fixing housing 313, a rotation outer housing 314 and a sliding member 315, wherein the rotation fixing housing 313 is connected to the link fixing member 311, a sliding rail 3131 is formed on a side of the rotation fixing housing 313 facing the rotation outer housing 314, the rotation outer housing 314 is connected to the toothed ring 32, one end of the sliding member 315 is connected to the rotation outer housing 314, and the other end thereof is slidably connected to the sliding rail 3131.

It can be understood that the rotating housing 314 can drive the sliding element 315 to rotate relative to the rotating stationary housing 313 along the extending direction of the sliding rail 3131, and when the length of the sliding rail 3131 is limited, the rotating housing 314 can further limit the rotating angle relative to the rotating stationary housing 313.

Further, since the rotation fixing housing 313 is connected to the link fixing member 311 and the rotation fixing housing 313 is connected to the link fixing member 311, that is, the length of the slide rail 3131 is set to further limit the rotation angle of the knee joint assembly 30, so that the lower leg can be swung sufficiently without compressing the tension spring 34 in the knee joint assembly 30 and preventing the lower leg from being swung sufficiently.

Alternatively, the sliding rail 3131 may be a recess formed on a side surface of the rotating fixing housing 313 facing the rotating housing 314, and the sliding element 315 is a screw rod, and one end of the screw rod is embedded in the recess and can move back and forth along an extending direction of the recess. In other embodiments, the sliding rail 3131 may also be a curved rail with a set length protruding from a side of the rotating fixing housing 313 facing the rotating housing 314, and the sliding element 315 is a link rod with one end corresponding to the curved rail and capable of moving back and forth along the extending direction of the curved rail, and the other end is fixedly connected to the rotating housing 314, which is not limited in this application.

In an embodiment, the first housing 31 further includes a second connecting rod clamp 316, and the second connecting rod clamp 316 is connected to the rotating housing 314 and cooperates with the rotating housing 314 to fixedly connect the first housing 31 to the second connecting rod 40, so as to be driven by the second connecting rod 40 to rotate in the same direction or drive the second connecting rod 40 to rotate in the same direction.

Referring to fig. 6, fig. 6 is a detailed structural diagram of the gear ring, the spur, the first connecting member and the second connecting member of the knee joint assembly of fig. 1.

In an embodiment, the inner diameter of toothed ring 32 is two times larger than the outer diameter of straight teeth 33, and accordingly, the radii of the two are also equal to the multiple, as shown in fig. 6, R1 is two times larger than R2, and when tension spring 34 is in the initial state, the connection point with straight teeth 33 is at the position of the center of circle of toothed ring 32, and the extension direction of tension spring 34 is perpendicular to the connection line between the connection point and the center of circle of straight teeth 33.

Note that, as shown in fig. 7 and 8, fig. 7 is a schematic structural view of the universal gear mechanism, and fig. 8 is a schematic structural view of the inverted universal gear mechanism. The design concept of the toothed ring 32 and the straight teeth 33 makes reference to a novel gravity balance structure for carrying a single degree of freedom rotational load.

It is known that a universal gear mechanism can convert rotary motion into linear motion by means of gear pairs. The universal gear mechanism is composed of a sun gear, an arm and a ring gear. When the sun gear has a diameter half that of ring gear, point A on the sun gear moves linearly along the dotted line PQ shown in FIG. 7.

It follows that this linear motion characteristic has prompted us to apply a universal gear mechanism to design an inverted universal gear mechanism as shown in figure 8. In order to respond to the rotation movement of the load in the gravity balancer, a gear arm is selected as a frame, and a ring gear is selected as an input arm of the load, so that the inverted universal gear mechanism is formed. The initial position of point a coincides with the origin O point of the reference coordinate system. Therefore, when the load input arm is rotated by the angle θ, the ring gear ringgear will also be rotated by the angle θ, and the point a moving along the PQ line will have the following displacement relationship:

S(θ)＝2rsin(θ)；

where S is the displacement of point A relative to the origin O and r is the radius of sun gear.

Therefore, if an extension spring is disposed between the point Q and the point a or between the point P and the point a such that the extension amount of the spring is equal to the length of the linear motion of the point a (i.e., S), the elastic potential energy E of the spring is _k Comprises the following steps:

in one embodiment, the knee joint assembly 30 further comprises a first connecting member 35 and a second connecting member 36, wherein the first connecting member 35 is connected to one side of the toothed ring 32, the second connecting member 36 is connected to one side of the straight teeth 33 near the vertex of the outer ring thereof corresponding to the second connecting member 36, and opposite ends of the tension spring 34 are respectively connected to the first connecting member 35 and the second connecting member 36 to be connected to the toothed ring 32 and the straight teeth 33 through the first connecting member 35 and the second connecting member 36.

Referring to fig. 9, fig. 9 is an exploded view of the hip joint assembly of the walking assist exoskeleton device of fig. 1. In this embodiment, the hip joint assembly 10 further comprises a second housing 11, a cam 13 and a spring 12.

Specifically, the second housing 11 is adapted to be worn about the hip joint of a user, and the cam 13 is coupled to the second housing 11 and the other end of the first connecting rod 20 distal from the knee joint assembly 30.

The elastic member 12 specifically includes a first supporting leg 121 and a second supporting leg 122, the first supporting leg 121 and the second supporting leg 122 are disposed at a set angle in an initial state, and an included angle between the first supporting leg 121 and the second supporting leg 122 can be gradually increased under the action of a corresponding external force, and when the external force disappears, the elastic member is restored by springing back.

Specifically, the first leg 121 is connected to the second housing 11, and the second leg 122 abuts against the first side 131 of the cam 13, so that when the first connecting rod 20 drives the cam 13 to rotate relative to the first leg 121 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, the cam 13 of the hip joint assembly 10 can be driven by the first connecting rod 20 to rotate relative to the first leg 121 in the first direction, so that the second leg 122 moves away from the first leg 121 along a part of the arc surface of the first side 131 of the cam 13, that is, the included angle between the second leg 122 and the first leg 121 gradually increases under the action of external force, thereby storing 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 13 to rotate towards the first direction relative to the first leg 121 disappears, and at this time, the elastic member 12 of the hip joint assembly 10 will rebound to reset, that is, the included angle between the second leg 122 and the first leg 121 will return to the initial state, the second leg 122 will move to reset close to the first leg 121 to drive the cam 13 to rotate towards the second direction relative to the first leg 121, and the cam 13 will drive the first 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, provide an upward lifting force and a forward swinging force for the human body.

The first side 131 of the cam 13 is perpendicular to the second side 132 thereof, and the extending direction of the first connecting rod 20 is parallel to the second side 132. And the first side 131 specifically refers to an outer peripheral surface of the cam 33, i.e., an annular curved surface.

Continuing to refer to fig. 10-11, fig. 10 is a detailed structural view of the elastic member of the hip joint assembly of fig. 9, and fig. 11 is a detailed structural view of the cam of the hip joint assembly of fig. 9.

In one embodiment, the elastic element 12 is embodied as a torsion spring mechanism, and the elastic element 12 further includes a roller 123, the second leg 122 includes a first rod 1221 and a second rod 1222, one end of the first rod 1221 is connected to the first leg 121, the other end of the first rod 1221 is vertically connected to the second rod 1222, and the roller 123 is sleeved on the second rod 1222 and abuts against the first side 131.

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 123 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 123.

In one embodiment, the projection of the partial arc surface of the first side 131 of the cam 13 on the second side 132 thereof further satisfies a set curve function relationship; wherein the second side 132 is perpendicular to the first side 131.

Note that, as shown in fig. 12, fig. 12 is a schematic view of a rope winding cam system. Therein, use is made of a rope-wound spring system based on a cam 13, i.e. cam a in the figure, in particular by means of a linear spring, cam 13 and a spring wound around and connected to cam 13The inelastic wire achieves the effect of simulating a torsion spring arrangement. When the cam 13 rotates, the inelastic wire wound around the cam 13 pulls the spring to generate a torque, and different torque deformation angle correspondences, namely, F (u) can be obtained by designing different profiles of the cam 13 and the like _T ) Corresponding to 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)

The free angle of the torsion spring mechanism (the angle between the two legs when no load is present) is 90. According to the structural space consideration given by the hip joint exoskeleton, the diameter d of the torsion spring mechanism is given to be 2mm, and the number n of turns of the torsion spring mechanism is given to be 6. The torsion spring mechanism 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. the resistance of the material from which the torsion spring mechanism is madeAn amount of elastic deformation, an indication of material stiffness;

working limit torque

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

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

Specifically, as shown in fig. 13, fig. 13 is a schematic diagram of a cam profile fitting curve. By discussing that the continuity of the moment and the moment derivative is a necessary condition for the contour smoothing of the cam 13, 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 13 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 _i and (. 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 (α ₁ )＝G” ₁ (α ₁ )；

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 _i N represents 4N unknown coefficients.

It can be understood that, in a specific embodiment, the projection of the part of the arc surface of the first side 131 of the cam 13 on the second side 132 thereof further satisfies the curve function exemplified above as shown in fig. 13, and the part of the arc surface satisfying the curve function corresponds to the part of the arc surface of the second leg 122 sliding back and forth along the first side 131 of the cam 13 during the walking process of the human body.

It will be appreciated that the design of the hip joint assembly 10 is based on the cooperation of the shaped ball torsion spring and the cam 13 to compensate for the weight of the thigh, and that the torque of the internal torsion spring is converted into a balancing torque of the hip and knee joints in the later stages of the stance phase of gait to overcome the effect of gravity. The design of the knee joint exoskeleton module refers to the structural principle of a spring gravity balance device and is used for bearing the single-degree-of-freedom rotating load. In gait, the energy of the swing of the crus when the ankle joint is bent is absorbed and released in a swing state. After wearing, the knee joint module can help the shank to be pushed out forwards in the dynamic swing state, so that the falling caused by insufficient swing of the shank is avoided.

With continuing reference to fig. 14, fig. 14 is a schematic diagram of a detailed construction of the transmission member of the hip joint assembly of fig. 9.

In one embodiment, the hip joint assembly 10 further includes a transmission member 14, one end of the transmission member 14 is connected to the first connecting rod 20, and the second side surface 132 of the cam 13 is formed with a first through hole 1301, so that the other end of the transmission member 14 can pass through the first through hole 1301 to be fixedly connected with the cam 13.

Therefore, the first connecting rod 20 drives the transmission member 14 to rotate, and then drives the cam 13 to rotate through the transmission member 14, so that the second leg 122 can move away from the first leg 121 along the partial arc surface of the first side surface 131, and elastic energy storage is performed. When the second leg 122 is moved and reset close to the first leg 121, the cam 13 can be driven to rotate in a second direction opposite to the first direction relative to the first leg 121, and then the driving member 14 can be driven to rotate by the cam 13, so as to drive the first connecting rod 20 to rotate by the driving member 14. Wherein the second side 132 is perpendicular to the first side 131.

In an embodiment, a part of the structure of the transmission member 14 protrudes from the first through hole 1301 to form a protruding portion 141, the protruding portion 141 abuts against the second housing 11, and a radial dimension of the protruding portion 141 is greater than a radial dimension of the first through hole 1301, so that the cam 13 can be reliably sleeved on the transmission member 14 without directly contacting the second housing 11, and the transmission member 14 can be driven to rotate more smoothly.

In an embodiment, the hip joint assembly 10 further includes a clamp spring 15, a clamp spring groove 3401 is formed on a side surface of the transmission member 14 facing the hole wall of the first through hole 1301, and the clamp spring 15 is sleeved in the clamp spring groove 3401 to limit the transmission member 14 from moving along the central axis direction of the first through hole 1301.

Further, the first through hole 1301 of the cam 13 further includes a concave portion 1303 concave toward the first side surface 131, and a flat key portion 142 is formed on a side surface of the transmission member 14 facing the hole wall of the first through hole 1301 in a protruding manner, and the flat key portion 142 is embedded in the concave portion 1303, so as to limit the rotational movement of the transmission member 14 relative to the cam 13, that is, to enable the transmission member 14 to be fixedly connected with the cam 13.

Optionally, the second side 132 of the cam 13 is further formed with a second through hole 1302, and the second through hole 1302 is meniscus-shaped and spaced apart from the first through hole 1301, so as to ensure that the center of gravity of the cam 13 is near or coincident with the geometric center thereof as much as possible, and reduce the weight of the cam 13 as much as possible, so as to reduce the wearing burden of the corresponding human body. In other embodiments, the second through hole 1302 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 121 and the second leg 122 in the initial state is 85-95, and the angle at which the first leg 121 travels relative to the second leg 122 varies in the range of 85-135.

In one embodiment, the hip joint assembly 10 further comprises a connecting rod fixing shell 16, wherein the connecting rod fixing shell 16 is fastened to a side surface of the transmission member 14 away from the second housing 11, and the other end of the first connecting rod 20 is connected between the transmission member 14 and the connecting rod fixing shell 16 so as to be mutually fitted and fixed by the transmission member 14 and the connecting rod fixing shell 16.

In a particular embodiment, the hip joint assembly 10 specifically comprises: the connecting rod fixing device comprises a second shell 11, a cam fixing shell member 17, a cam 13, an elastic member 12, a roller 123, a snap spring 15, a transmission member 14, a connecting rod fixing shell 16, four M3X 8 bolts, one M2.5X 8 bolt and one M4X 16 bolt. The knee joint component 30 specifically includes: the connecting rod clamping plate comprises a rotary fixed shell 313, a rotary outer shell 314, a connecting rod fixing piece 311, a toothed ring 32, a straight tooth 33, a first connecting piece 35, a second connecting piece 36, a first connecting rod clamping plate 312, a second connecting rod clamping plate 316, three M3X 8 bolts, two M2X 8 bolts, one M3X 8 bolt, four M2X 6 bolts and one M3X 10 bolt.

The bolts of each specification are specifically used for connecting and fixing the structural members in the hip joint assembly 10 and the knee joint assembly 30, and are not described herein again.

Further, the hip joint assembly 10 is provided with two first connecting rods 20 fixed between the connecting rod fixing shell 16 and the transmission member 14, when a human body gait occurs, the first connecting rods 20 swing along with thighs, the first connecting rods 20 drive the transmission member 14 to rotate, the cam 13 is axially fixed with the transmission member 14 through a shaft shoulder, a clamp spring groove 1401 is reserved on the transmission member 14, and when one side of the cam 13 is axially contacted with the transmission member 14, the other side of the cam is axially fixed through the clamp spring 15. Meanwhile, a flat key portion 142 is formed on the transmission member 14, so that the transmission member 14 can be circumferentially and rotationally fixed with the cam 13.

The motion principle of the elastic element 12, for example, the torsion spring mechanism and the cam 13 in cooperation in gait is specifically as follows: when the sole of the swing side contacts the ground, the roller 123 on the torsion spring mechanism contacts the cam 13, at this time, the leg on one side of the walking assisting exoskeleton device 1 enters a supporting state, the thigh swings in the opposite direction of the movement direction, the first connecting rod 20 drives the transmission part 14 to rotate, the diameter of the contact point of the cam 13 and the roller 123 is continuously increased, the roller 123 further drives the corresponding pin of the torsion spring mechanism to twist, the torsion spring mechanism generates torque, and the torsion spring mechanism generates the maximum working torque at the end stage of the supporting state.

When the swing state is entered, the thighs swing in the same direction of the movement direction, the first connecting rod 20 drives the transmission piece 14 to rotate, the diameter of the contact point of the cam 13 and the roller 123 is continuously reduced, the torque stored by the torsion spring mechanism in the supporting state is released along with the gait entering the swing state, the released torque drives the cam 13 to rotate, the transmission piece 14 and the connecting rod fixing shell 16 drive the first connecting rod 20 to swing, the first connecting rod 20 is connected with the knee joint component 30, and the swing of the knee joint component 30 drives the corresponding knee joint of the human body to swing out in the walking direction.

It will be appreciated that the torsion spring mechanism cam 13 can be space saving and relatively lightweight in a compact, complex assembly environment. The hip joint assembly 10 achieves absorption of the energy of negative work done by the knee joint in gait, providing a forward pulling force on the knee joint during the swing phase.

The rotary housing 314 and the ring gear 32 are fixed by M2 × 8 bolts, and the second connecting rod 40 is fixed between the rotary housing 314 and the second connecting rod clamp 316, and the second connecting rod 40 is connected to the lower leg assembly 50. The toothed ring 32 is matched with the straight teeth 33, and a shaft fixing frame with the straight teeth 33 is designed on the connecting rod fixing piece 311.

Wherein, a first connecting piece 35 and a second connecting piece 36 are respectively fixed on the gear ring 32 and the straight tooth 33 through M2 × 6 bolts, and the second connecting piece 36 and the first connecting piece 35 are respectively fixed at two ends of the tension spring 34. When the shank swings in the opposite direction of the moving direction, the shank component 50 drives the second connecting rod 40 to rotate, the second connecting rod 40 drives the rotary shell 314 to rotate, the rotary shell 314 drives the toothed ring 32 to rotate, the toothed ring 32 drives the straight teeth 33 to rotate, and the rotation of the gear pair causes the tension spring 34 fixed on the second connecting piece 36 and the first connecting piece 35 to be stretched. The above description implements the motion principle of the universal gear mechanism in the description of the exoskeleton principle of the knee joint, and converts the rotation motion of the gear pair into the linear motion of the tension spring 34. When the gait enters the next stage, namely after the dorsal extension occurs, when the lower leg on the side where the exoskeleton is worn moves in the same direction of the movement direction, the tension spring 34 is released from the stretching state, the energy is released to assist the toothed ring 32 and the straight teeth 33 to move, namely the knee joint exoskeleton rotates, the second connecting rod 40 is driven to swing, and the second connecting rod 40 is connected with the lower leg through the lower leg assembly 50, namely the lower leg is driven to swing. In other aspects, the first link splint 312 and the link fixing member 311 are fixed with carbon fiber rods through 25-M3 × 10 bolts, and are connected with the hip joint exoskeleton to transmit the work of the hip joint exoskeleton on the knee joint.

Meanwhile, the knee joint rotation component set, namely the straight teeth 33, the toothed ring 32 and the tension spring 34, is fixed by the rotation fixing shell 313 and the connecting rod fixing piece 311, the rotation fixing shell 313 and the connecting rod fixing piece 311 are fixed through M3 × 8 bolts, a sliding rail 3131 is designed on the side of the rotation fixing shell 313, which is contacted with the rotation outer shell 314, and the upper end of the M2 × 8 bolt is embedded in the sliding rail 3131 when the rotation fixing shell 313 is contacted with the rotation outer shell 314, so that the rotation component set can fully slide in the fixing of the rotation fixing shell 313 and the connecting rod fixing piece 311, and the rotation of the knee joint exoskeleton is limited through the sliding rail 3131. The reason for the limitation is that the tension spring 34 in the rotary member is not compressed while the lower leg is sufficiently swung, and the lower leg is prevented from being sufficiently swung out.

In gait, the knee joint exoskeleton absorbs energy generated by the swing of the lower leg when the ankle joint is bent, and releases the energy when the swing is dynamic, so that the most intuitive feeling is that the falling caused by insufficient swing of the lower leg can be compensated.

The various components of the exoskeleton are connected using first and second connecting

rods

20 and 40, which allow for the replacement of carbon fiber rods of different lengths to match the length parameters of the lower limbs of different wearers.

When the walking assisting exoskeleton device 1 is worn, the shank component 50 is arranged above the ankle joint to work in cooperation with the knee joint exoskeleton and transmit energy generated by shank swing during gait to the exoskeleton.

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.

After the walking assisting exoskeleton device 1 prototype is manufactured, the exoskeleton is worn on the left leg of a healthy subject to carry out a three-dimensional motion capture experiment. Human gait data and plantar pressure data are obtained, kinematics and dynamics analysis are carried out on the data, and the experimental process is as follows:

the subject is required to perform three replicates to ensure at least one set of selectable data. Experiments are combined with the exoskeleton action principle, the right leg is advanced into the force measuring plate to collect gait data during each gait, and the change of the kinematics parameters of the knee joint after the left leg enters the swing state is observed.

The purpose of this experiment is to compare the kinematics parameter changes of the left and right knee joints when the exoskeleton is worn and the kinematics parameter changes of the left knee joint when the exoskeleton is worn and when the exoskeleton is not worn under the same gait data.

As shown in fig. 15, fig. 15 is a schematic diagram of the change of the knee joint angle with the gait cycle, which is the change of the left and right knee joint angles with the gait cycle when the exoskeleton is worn. It can be seen that wearing the exoskeleton does not have much effect on the peak angle of knee joint swing, but in the swing phase of the gait cycle (GaitCycle-L, gait cycle 0% -50%), the knee joint angle on one side of wearing the exoskeleton is close to zero degrees, indicating that the swing is more sufficient, and from the amplitude of the knee joint angle, one side of wearing the exoskeleton is increased by approximately ten degrees compared to the other side, it can be analyzed that there is an increase in both knee joint acceleration and angular acceleration for the subject when wearing the exoskeleton.

As shown in fig. 16, fig. 16 is a schematic diagram of the change of knee joint angular velocity with gait cycle, which is the change of knee joint angular velocity with gait cycle when the exoskeleton is worn. It can be seen that there is approximately a twenty-five percent increase in the angular velocity of the knee joint on the side wearing the exoskeleton during the gait support phase.

As shown in fig. 17, fig. 17 shows the change of the left knee joint angle with the gait cycle, which is a parameter change of the left knee joint angle. The blue line is the change of knee joint angle when the examinee wears the exoskeleton, and the yellow line is the change of knee joint angle when the examinee is in normal gait. It can be seen that the knee angle is about ten degrees lower with the exoskeleton worn at pendulum dynamics (GaitCycle-L0% -50%) than without the exoskeleton, indicating that the lower limbs swing more fully after the exoskeleton is worn. Meanwhile, the swing speed and the swing acceleration are also obviously improved.

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 beneficial effect of this application is: different from the prior art, the hip joint assembly, the first connecting rod, the knee joint assembly, the second connecting rod and the hip joint assembly provided by the application comprise a first shell, a toothed ring, a straight tooth and a tension spring, wherein the hip joint assembly, the first shell and the shank assembly are respectively worn on a hip joint part, a knee joint part and a shank of a user; wherein, the ring gear is connected in first casing, the straight-tooth meshing is in the inner ring of ring gear, the relative both ends of extension spring are connected respectively in ring gear and straight-tooth, and the extending direction of extension spring passes through the centre of a circle of ring gear, when driving the ring gear to rotate to first direction at first casing, the ring gear can drive the straight-tooth and rotate to first direction, drive extension spring along its extending direction tensile motion through the straight-tooth, and elasticity energy storage, thereby can be when extension spring resilience resets, drive the second direction rotation that the straight-tooth is relative with first direction by the extension spring, the straight-tooth drives the ring gear and rotates to the second direction, the ring gear drives first casing and rotates to the second direction, thereby can avoid using extra power device to provide the helping hand, and direct work load accumulation in the in-process stage of human walking, and feed back to the human body, in order to reach the purpose of supplementary human walking. Therefore, the walking assisting exoskeleton device can help patients with walking dysfunction, such as patients with knee damage, recover natural gait, improve walking ability, realize motor function rehabilitation and enhance independent life quality by wearing the walking assisting exoskeleton device; 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 walking stick can be coordinated with the human 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 hip joint assembly for wearing on a hip joint portion of a user;

a first connecting rod, one end of which is connected to the hip joint assembly;

the knee joint component comprises a first shell, a toothed ring, a straight tooth and a tension spring, wherein the first shell is connected to the other end of the first connecting rod and used for being worn at the knee joint part of a user; when the first shell drives the gear ring to rotate towards a first direction, the gear ring drives the straight teeth to rotate towards the first direction, the straight teeth drive the tension spring to stretch along the extension direction of the tension spring, and when the tension spring rebounds and resets, the tension spring drives the straight teeth to rotate towards a second direction opposite to the first direction, the straight teeth drive the gear ring to rotate towards the second direction, and the gear ring drives the first shell to rotate towards the second direction;

one end of the second connecting rod is connected to the first shell;

and the lower leg assembly is connected with the other end of the second connecting rod and is used for being worn on the lower leg of the user.

2. The walking assist exoskeleton device of claim 1,

the inner diameter of the toothed ring is twice of the outer diameter of the straight tooth, the connecting point of the tension spring and the straight tooth is the circle center position of the toothed ring in the initial state, and the extending direction of the tension spring is perpendicular to the connecting line of the connecting point and the circle center of the straight tooth.

3. The walking assist exoskeleton device of claim 1 or 2,

the knee joint subassembly still includes first connecting piece and second connecting piece, first connecting piece connect in on the side of ring gear, the second connecting piece corresponds the second connecting piece connect in be close to the position department on its outer loop summit on the side of straight-teeth, the relative both ends of extension spring connect respectively in first connecting piece with the second connecting piece.

4. The walking assist exoskeleton device of claim 1,

the first shell comprises a connecting rod fixing piece and a first connecting rod clamping plate, the connecting rod fixing piece is connected to the first shell, and the first connecting rod clamping plate is connected to the connecting rod fixing piece and matched with the connecting rod fixing piece to be fixedly connected with the first connecting rod.

5. The walking assist exoskeleton device of claim 4,

first casing still includes rotatory set casing, rotatory shell and slider, rotatory set casing connect in the connecting rod mounting, rotatory set casing towards be formed with the slide rail on a side of rotatory shell, rotatory shell connect in the ring gear, the one end of slider connect in rotatory shell, the other end sliding connection of slider in the slide rail.

6. The walking assist exoskeleton device of claim 5,

the first shell further comprises a second connecting rod 40 clamping plate, and the second connecting rod 40 clamping plate is connected to the rotating shell and matched with the rotating shell to be fixedly connected with the second connecting rod.

7. The walking assist exoskeleton device of claim 1,

the hip joint component comprises a second shell, a cam and an elastic piece, wherein one end of the second shell, which is connected with the first connecting rod, is used for being worn at a hip joint part of a user, the cam is connected with the shell and the other end, which is far away from the knee joint component, of the connecting rod, the elastic piece 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, and the second supporting leg is abutted against a first side face of the cam; when the first connecting rod drives the cam to rotate towards the first direction, the cam drives the second support leg to move away from the first support leg along a part of arc surface of the first side surface, and when the second support leg rebounds and resets close to the first support leg, the second support leg drives the cam to rotate towards the second direction relative to the first support leg, and the cam drives the first connecting rod to rotate towards the second direction.

8. The walking assist exoskeleton device of claim 7,

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.

9. The walking assist exoskeleton device of claim 7,

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.

10. The walking assist exoskeleton device of claim 7,

the hip joint component further comprises a transmission piece, one end of the transmission piece is connected to the first 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 first 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.

11. The walking assist exoskeleton device of claim 10,

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.

12. The walking assist exoskeleton device of claim 11,

13. The walking assist exoskeleton device of claim 10,

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.

14. The walking assist exoskeleton device of claim 10,

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 second shell, of the transmission piece, and the other end of the first 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.

15. The walking assist exoskeleton device of any one of claims 10 to 14,

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.

16. The walking assist exoskeleton device of any one of claims 7 to 14,

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.