CN107174488B

CN107174488B - A wheeled drive self-balancing power ectoskeleton of sole for spinal cord injury patient

Info

Publication number: CN107174488B
Application number: CN201710236659.0A
Authority: CN
Inventors: 季林红; 马青川
Original assignee: Tsinghua University
Current assignee: Tsinghua University
Priority date: 2017-04-12
Filing date: 2017-04-12
Publication date: 2020-03-20
Anticipated expiration: 2037-04-12
Also published as: CN107174488A

Abstract

The invention discloses a sole wheel type driving self-balancing power exoskeleton for a spinal cord injury patient, which comprises a hip joint, a knee joint, an ankle joint, a sole driving module, a pelvis, a femur and a tibia. The ankle joint adopts an unpowered passive joint, the sagittal plane and the coronal plane respectively have a rotational degree of freedom, the knee joint adopts an active joint driver, the hip joint is an active joint driver or a controllable driver, the knee joint and the hip joint have a rotational degree of freedom on the sagittal plane, and the kinematics and the dynamics balance on the coronal plane are matched with the advantage that the two feet are always landed under the action of the foot bottom wheel type driving; the pelvis is provided with the supporting device, the advantages that the feet are always landed under the driving of the foot bottom wheels are utilized, the weight of the human body is transmitted to the ground through the supporting device and the exoskeleton, and the weight of the human body to be restrained by the exoskeleton is effectively reduced; energy storage elements such as torsion springs are designed at joints, so that energy consumption of a driver caused by vertical load fluctuation in the walking motion process can be reduced.

Description

A wheeled drive self-balancing power ectoskeleton of sole for spinal cord injury patient

Technical Field

The invention belongs to the technical field of medical instruments, and particularly relates to a powered lower limb medical exoskeleton technology.

Background

Spinal cord injury is a severe disease of loss of the lower extremity motor system and can be classified into paraplegia and quadriplegia according to the degree of injury. Patients with spinal cord injury need to rely on aids to achieve basic life due to loss of motor function in the lower limbs. The powered lower limb exoskeleton can assist a patient to realize upright walking, so the powered lower limb exoskeleton becomes intelligent medical rehabilitation equipment with development potential at present, and the patient with spinal cord injury cannot ensure walking balance by the patient, so the movement balance becomes a key point and a difficult point in exoskeleton design.

There are three main types of motion balance methods that have been put into practical use: the first is a method using auxiliary devices, and most of the current exoskeletons rely on elbow bends or walking frames to ensure balance, including israel's ReWalk, Ekso and Inego which are commercially successful exoskeletons, but when using the exoskeletons, patients need to have good upper limb functions, so the exoskeletons can only be applied to low-level spinal cord injuries and cannot be applied to high-level or quadriplegia patients; the second is a method adopting a self-motion balance algorithm, which is mainly a Zero Moment Point (ZMP) balance algorithm widely applied at present, but the ZMP balance algorithm can only ensure the balance of a sagittal plane but cannot realize the balance of a coronal plane, so that the ZMP balance algorithm is mostly applied to dynamic exoskeletons for helping healthy people to enhance the capability, and when the ZMP algorithm is applied to patients with lower limb functional impairment, certain exoskeletons adopting the ZMP algorithm such as Japanese HAL and the like still need to rely on elbows to ensure walking safety; the third method is mainly a balance method adopting a self-mechanical structure, REX of New Zealand is an exoskeleton adopting the method in the first money in the world, the exoskeleton adopts the self-mechanical structure to realize non-crutch walking balance, the use experience of Handsfree is achieved, the exoskeleton can be applied to not only paraplegia at low positions but also quadriplegia which can not use elbow crutches, but the REX can only be used for walking at low speed to avoid dynamic load to ensure balance at present and can not realize rapid movement balance.

In the process of using the exoskeleton, the human-computer movement coordination is a key evaluation index. The exoskeleton drives the human body to move by adopting a mechanical mode, so that the human body is constrained to move along a set track, the mass of the exoskeleton is generally smaller than that of the human body, and the exoskeleton is constrained to have large mass by small mass, so that the situation that the human body cannot move along with the exoskeleton, namely the human-computer movement is uncoordinated, often occurs. The key to improving the coordination of the man-machine movement is to reduce the mass of the human body to be restrained by the exoskeleton. The current approach is to use a Body Weight Support system (BWS). However, current BWS systems are complex in design and have little to no mobility, and are therefore often used in treadmill-based exoskeleton systems. In addition, because the walking process of the human body belongs to periodic movement, a large amount of energy is used for offsetting load fluctuation in the vertical direction in the joint driving type exoskeleton, and the energy really used for advancing is small. The energy storage element can effectively reduce the energy consumption of load. However, this current approach is difficult to implement in a joint-driven exoskeleton because the joint-driven exoskeleton will experience periods of single support and dual support during walking, and the legs will not land all the time.

Since more than half of spinal cord injured patients are cervical level injuries, C5 is most second thoracic level (T1-T12) (NSCISC2015), but most exoskeletons can only cover thoracic level injured patients at present, the development of a powered exoskeleton using a non-abductive balance mode like REX is of practical significance for covering the whole spinal cord injured population. But at the same time such exoskeletons should have fundamental structural improvements over REX to achieve motion balance capability. Most of the current exoskeletons, including REX, are structurally related to joint-driven exoskeletons. The exoskeleton walking mode is closer to the human body, and the user needs to lift feet and then take a step forwards when walking. The extra foot-lifting time limits the forward balancing speed of this type of exoskeleton. In contrast, a wheel drive mechanism, which can achieve motion balance by rapid rolling of wheels while advancing, has been well used in balance vehicles such as Segway and wheeled robots by means of an inverted pendulum balance method. In addition, by matching with a proper weight support design and utilizing the advantage that the two feet are driven to land all the time by wheels, the weight of the human body can be transmitted to the ground through the self structure of the exoskeleton, the man-machine movement coordination is effectively improved, and the performance requirement and the energy consumption of the driver are reduced.

On the basis of analyzing the existing power lower limb exoskeleton and wheel type driving systems, the invention provides a self-balancing power lower limb exoskeleton driven by adopting a sole wheel type, the exoskeleton can realize the motion balance of a sagittal plane and a coronal plane at the same time through special mechanical mechanism design without depending on auxiliary instruments such as elbow bends and the like; the invention simultaneously adopts the weight support design, and realizes the function similar to a BWS system on the mobile wearable exoskeleton.

The exoskeleton of the invention can be applied to paraplegic patients and also can be applied to quadriplegia patients who have limited upper limb functions and can not use elbow crutches.

Disclosure of Invention

In order to solve the problems that the existing lower limb exoskeleton applied to spinal cord injury patients can only cover paraplegic patients, has limited motion balance capability and is inconsistent in man-machine motion, the invention discloses a lower limb exoskeleton adopting foot wheeled drive and power joints, which can realize motion balance in a sagittal plane and a coronal plane without elbow crutch assistance, help the whole spinal cord injury crowd to realize upright double-leg walking and rehabilitation training and improve the man-machine motion coordination.

In order to realize the purpose, the technical scheme adopted by the invention is as follows:

a sole wheel type driving self-balancing power exoskeleton for a spinal cord injury patient comprises a hip joint 1, a knee joint 2, an ankle joint 3, a sole driving module 4, a pelvis 5, a femur 7 and a tibia 8, wherein the hip joint 1, the femur 7, the knee joint 2, the tibia 8, the ankle joint 3 and the sole driving module 4 are arranged from top to bottom and are arranged in a bilateral symmetry mode, the hip joint 1 is connected with the knee joint 2 through the femur 7, the knee joint 2 is connected with the ankle joint 3 through the tibia 8, and the ankle joint 3 is connected with the sole driving module 4.

Preferably the degrees of freedom of the exoskeleton are arranged such that the hip joint 1 has one degree of freedom of rotation in the sagittal plane, the knee joint 2 has one degree of freedom of rotation in the sagittal plane, and the ankle joint 3 has one degree of freedom of rotation in each of the sagittal and coronal planes.

Preferably, the hip joint 1 is an active joint actuator or a controllable actuator; the knee joint 2 is an active joint driver and comprises an energy storage element; the ankle joint 3 is an unpowered passive joint and comprises energy storage elements in the sagittal plane and the coronal plane respectively.

Preferably, the pelvis 5 comprises support means to lift the user from the crotch, transferring the weight of the person from the support means through the exoskeleton to the ground, reducing the weight of the person to which the exoskeleton is required to restrain.

Preferably, the hip joint 1 comprises a hip joint support strip 16, a thrust bearing 17, a special-shaped nut 18, an electromagnetic brake fixing screw 19, an inner hip joint 20, an electromagnetic brake 21, an outer hip joint 22, a hip joint belt key shaft 23 and a hip joint fixing screw 24, the hip joint support strip 16 is provided with a plurality of adjustable screw holes, the hip joint support strip 16 and the pelvis transverse support 10 are screwed into different adjusting holes through bolts to realize position adjustment, the inner hip joint 20 and the outer hip joint 22 are connected through the hip joint fixing screw 24, a hip joint rotating pair is formed by the thrust bearing 17, the special-shaped nut 18 and the hip joint belt key shaft 23 together, the electromagnetic brake 21 is connected with the inner hip joint 20 through the electromagnetic brake fixing screw 19, the hip joint belt key shaft 23 is provided with a flat key, the flat key is matched with a movable part key groove of the electromagnetic brake 21, when the electromagnetic brake 21 is in a non-enabling state, the movable part of the hip joint 1 freely rotates, when the electromagnetic brake 21 is in an enabled state, the hip joint 1 cannot rotate freely due to braking.

Preferably, the knee joint 2 comprises a driving motor 25, a knee joint upper part 26, a lower inner side knee joint 27, a knee joint lower part fixing screw 28, a knee joint torsion spring 29 and a lower outer side knee joint 30, the driving motor 25 is vertically arranged to reduce the overall transverse size, a speed reducer is integrated in the knee joint upper part 26, the lower inner side knee joint 27 and the lower outer side knee joint 30 are arranged in a bilateral symmetry mode, the knee joint torsion spring 29 is respectively installed in the hollow parts, connected with the lower inner side knee joint 27 and the lower outer side knee joint 30, of the knee joint upper part 26 through the knee joint lower part fixing screw 28, and the energy storage element is used as an energy storage element of the knee joint 2 to reduce the maximum power required by the driving motor 25 and reduce.

Preferably, the ankle joint 3 comprises an ankle joint coronal plane shaft 31, a vertical rear side ankle joint 32, an ankle joint transverse part 33, a vertical front side ankle joint 34, an ankle joint torsion spring 35 and an ankle joint sagittal plane shaft 36, the vertical rear side ankle joint 32 and the vertical front side ankle joint 34 are arranged in a bilateral symmetry manner and are connected through the ankle joint sagittal plane shaft 36, the ankle joint transverse part 33 is connected with the sole wheel type driving module 4 through the ankle joint coronal plane shaft 31, the ankle joint transverse part 33 is arranged into an ankle joint movement form of a cross connecting shaft through the ankle joint coronal plane shaft 31 and the sagittal plane shaft 36, and the ankle joint torsion springs 35 are arranged between the ankle joint transverse part 33 and the vertical front side ankle joint 34 and between the ankle joint transverse part 33 and the foot wheel type driving module 4 as energy storage elements of the ankle joint 3.

Preferably, the support device for the pelvis 5 comprises a support base 6, a pelvis support plate 9, a transverse pelvis support 10, a lateral pelvis support 11, a support tube connector 12, a vertical tube 13, a tube connector 14 and a transverse tube 15, wherein the support base 6 is connected with the pelvis support plate 9 through the support tube connector 12, the vertical tube 13, the tube connector 14 and the transverse tube 15, the pelvis support plate 9 is arranged into a front block and a rear block, the front block and the rear block are connected through the lateral pelvis support 11, the hollow part of the pelvis support plate is used for installing a power supply and an electric control system, the transverse pelvis support 10 is symmetrically arranged at the left and the right and is connected with the lateral pelvis support 11 through screws, the transverse pelvis support 10 is provided with adjustable screw holes through which the pelvis 5 can be connected with the hip joint 1, the support base 6 is respectively adjusted in the front and rear directions and in the up and down directions through a plurality of, The up-down and lateral directions are adjusted.

Preferably, the sole driving module 4 comprises a wheel driver and wheels, wherein the front wheel of the wheels is an unpowered auxiliary wheel, and the rear wheel is a wheel hub motor.

Preferably, the hip joint 1, the knee joint 2, the ankle joint 3 and the sole driving module 4 are all made of aluminum alloy, the outer pelvis 5 is made of aluminum alloy except for the supporting seat 6, the supporting seat 6 is made of high-strength plastic and made of sponge cloth at the position in contact with a human body, and the femur 7, the tibia 8 and the pelvis supporting plate 9 are made of carbon fiber plates.

The invention can realize the following beneficial effects:

1) the mode of installing the wheel type driver on the sole can help a patient with spinal cord injury to use the exoskeleton to complete rehabilitation training without a crutch or a walking aid, and the device can be applied to paraplegia and also can cover a quadriplegia patient with the same loss of upper limb functions. Because the foot wheel type drive does not have the joint driving type exoskeleton foot lifting process, the rapid motion balance can be realized with less energy consumption. In the foot bottom wheel type drive, the drive actuator is positioned at the tail end of the kinematic chain, so that the whole thigh is used as a force arm to effectively reduce the torque required by the hip joint, further reduce the weight and the size of the drive, and effectively solve the problem that the design of the hip joint drive is difficult due to the fact that the hip joint movement force arm is small in the joint drive type exoskeleton. By the existing mature wheel-type driving motion balance control algorithm and the advantage of low requirements on power consumption and torque of wheel-type driving, the exoskeleton can realize the kinematics and dynamic balance in the sagittal plane under the requirement of a smaller power system.

2) A2-1-1 type mechanical degree of freedom arrangement mode is adopted, namely, one degree of freedom of rotation of the ankle joint in a sagittal plane and a coronal plane respectively, one degree of freedom of rotation of the knee joint in the sagittal plane and one degree of freedom of rotation of the hip joint in the sagittal plane. By matching the advantage that the pelma wheel drives the two feet to land all the time, the exoskeleton can balance the kinematics and dynamics in the coronal plane through the differential rotation between the joints between the two legs.

3) The support device is designed at the pelvis part by adopting a weight support design, and then the weight of the human body is transferred to the ground through the exoskeleton by utilizing the advantage that the pelma wheel type drive feet land all the time, so that the weight of the human body to be restrained by the exoskeleton is effectively reduced. Compared with a joint driving type exoskeleton which restrains a human body through physical interfaces such as a binding band, the exoskeleton can effectively improve the human-computer movement coordination.

4) Energy storage elements such as torsion springs are designed at joints, so that energy consumption of a driver caused by vertical gravity fluctuation in the walking motion process can be reduced. An effect similar to the BWS system in treadmill exoskeletons is achieved on mobile wearable exoskeletons.

Drawings

Fig. 1 is a schematic diagram of the overall structure of the plantar wheel type driving self-balancing power exoskeleton for spinal cord injury patients (all flexible straps and wires are not shown) of the invention;

FIG. 2 is a pelvic structure diagram of the exoskeleton of the present invention;

FIG. 3 is an exploded view of the hip joint of the exoskeleton of the present invention;

FIG. 4 is an exploded view of the knee joint of the exoskeleton of the present invention;

FIG. 5 is an exploded view of the ankle joint of the exoskeleton of the present invention;

the reference numerals in the figures are illustrated as follows:

1-hip joint, 2-knee joint, 3-ankle joint, 4-plantar drive module, 5-pelvis, 6-support, 7-femur, 8-tibia, 9-pelvis support plate, 10-pelvis transverse support, 11-pelvis lateral support, 12-support tube connection, 13-standpipe, 14-pipe connection, 15-cross pipe, 16-hip joint brace, 17-thrust bearing, 18-profile nut, 19-electromagnetic brake set screw, 20-medial hip joint, 21-electromagnetic brake, 22-lateral hip joint, 23-hip joint belt key shaft, 24-hip joint set screw, 25-drive motor, 26-knee joint upper part, 27-lower medial knee joint, 28-knee joint lower set screw, 29-knee joint torsion spring, 30-lower lateral knee joint, 31-ankle joint coronal shaft, 32-vertical posterior ankle joint, 33-ankle joint transverse part, 34-vertical anterior ankle joint, 35-ankle torsional spring, 36-ankle sagittal axis.

Detailed Description

The invention adopts the sole wheel type driver and the joint driver to realize the kinematics and dynamic balance of the sagittal plane under the non-crutch supporting condition. The design of 2-1-1 type mechanical freedom is adopted, namely, the ankle joint has one rotational freedom in the sagittal plane and the coronal plane respectively, the knee joint has one rotational freedom in the sagittal plane, and the hip joint has one rotational freedom in the sagittal plane. The mapping length of the two legs in the coronal plane can be changed through different joint angles between joints of the two legs, and the kinematics and dynamic balance of the exoskeleton in the coronal plane under the condition of uneven road surface or other interference is realized. This ectoskeleton adopts the weight to support the design, installs adjustable cushion in pelvis department to the design has the energy storage original paper on the joint, can transmit human body gravity to ground, and effectively reduce the energy consumption that the fluctuation of vertical direction bearing of the weight caused through the energy storage original paper, reduces joint driver performance requirement. The exoskeleton ankle joint adopts a passive joint, the knee joint adopts an active joint driver, and the hip joint can be designed into an active joint driver or a controllable driver according to the use requirement. When the hip joint adopts the active joint driver, a decoupling algorithm needs to be designed to realize motion decoupling between the plantar wheel type driver and the opposite hip joint. Mechanical decoupling can be achieved without the need to design specific motion algorithms when controllable brakes are employed. The exoskeleton femur, tibia, cushion and pelvis are all designed with adjustable mechanisms to adapt to users with different physical characteristics. The exoskeleton energy source and the electronic control system are both mounted at the pelvis, and transmit energy to the joint driver and the wheel driver through wires, and transmit motion feedback signals back to the electronic control system at the pelvis. Sensors for exoskeleton pose detection are also installed at the pelvis to detect exoskeleton motion poses in real time to control the drive elements.

In order to make the implementation objects, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be described in more detail below with reference to the accompanying drawings in the embodiments of the present invention. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The described embodiments are only some, but not all embodiments of the invention. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Like reference numerals refer to like elements throughout the description of the figures. It will also be understood that the term "and/or" as used herein includes any and all combinations of one or more of the associated listed items.

It will be further understood that when an element or unit is referred to as being "connected" or "coupled" to another element or unit, it can be directly connected or coupled to the other element or unit or intervening elements or units may also be present. Further, other words used to describe the relationship between components or units should be understood in the same manner.

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

As shown in fig. 1, the sole wheel driven self-balancing powered exoskeleton for spinal cord injury patients comprises a hip joint 1, a knee joint 2, an ankle joint 3, a sole driving module 4, a pelvis 5, a femur 7 and a tibia 8, similar to the division of the segments and joints of the lower limbs of the human body. The hip joint 1, the femur 7, the knee joint 2, the tibia 8, the ankle joint 3 and the sole driving module 4 are arranged from top to bottom and are arranged in bilateral symmetry, and are connected through the pelvis 5; the hip joint 1 is connected with the knee joint 2 through a femur 7, the knee joint 2 is connected with the ankle joint 3 through a tibia 8, and the ankle joint 3 is connected with the sole driving module 4.

As shown in fig. 2, the pelvis 5 of the exoskeleton is designed with a model of support means, including a support base 6, a pelvic support plate 9, a pelvic lateral support 10, a pelvic lateral support 11, a support tube connection 12, a vertical tube 13, a tube connector 14 and a transverse tube 15. Wherein, the supporting seat 6 is connected with the pelvis supporting plate 9 through a supporting tube connecting piece 12, a vertical tube 13, a pipe joint 14 and a horizontal tube 15; the pelvis supporting plate 9 is arranged into a front part and a rear part which are connected through a pelvis lateral bracket 11, and the hollow part is used for installing a power supply and an electric control system; the transverse pelvic support 10 is symmetrically arranged left and right and is connected with the lateral pelvic support 11 through screws, and the transverse pelvic support 10 is provided with a plurality of adjustable screw holes through which the pelvis 5 can be connected with the hip joint 1. The design can lift a user from the crotch, and the weight of the human body is transferred to the ground through the supporting device and the exoskeleton, so that the weight of the human body to be restrained by the exoskeleton is effectively reduced.

As shown by the arrows in fig. 2, in order to adapt to users with different physical characteristics, the support seat 6 can be adjusted in the front-back and up-down directions through a plurality of adjustable screw holes respectively arranged on the vertical tube 13 and the horizontal tube 15; the pelvis 5 can be adjusted in the front-back, up-down, and side-to-side directions by the transverse pelvis frame 10 and the lateral pelvis frame 11.

As shown in FIG. 3, the hip joint 1 of the exoskeleton comprises a hip joint branch 16, a thrust bearing 17, a special-shaped nut 18, an electromagnetic brake fixing screw 19, an inner hip joint 20, an electromagnetic brake 21, an outer hip joint 22, a hip joint key shaft 23 and a hip joint fixing screw 24. The hip joint supporting strip 16 and the pelvis transverse support 10 are screwed into different adjusting holes through bolts to realize position adjustment; the inner hip joint 20 and the outer hip joint 22 are connected through a hip joint fixing screw 24, and form a hip joint rotating pair through a thrust bearing 17, a special-shaped nut 18 and a hip joint key shaft 23; the electromagnetic brake 21 is connected with the inner hip joint 20 through an electromagnetic brake fixing screw 19; the hip-joint keyed shaft 23 is provided with a flat key which cooperates with a movable-part key groove (not shown) of the electromagnetic brake 21, the movable part of the hip joint 1 can rotate freely when the electromagnetic brake 21 is in a non-enabled state, and the hip joint 1 cannot rotate freely due to braking when the electromagnetic brake 21 is in an enabled state.

As shown in fig. 4, the exoskeleton's knee joint 2 includes a drive motor 25, a knee upper part 26, a lower medial knee 27, a knee lower fixation screw 28, a knee torsion spring 29 and a lower lateral knee 30. Wherein the drive motor 25 is vertically arranged to reduce the overall lateral dimension; the reducer is integrated in the upper part 26 of the knee joint; the lower medial knee joint 27 and the lower lateral knee joint 30 are arranged in bilateral symmetry and are connected through a lower knee joint fixing screw 28; the knee joint torsion springs 29 are respectively arranged in the hollow parts of the upper knee joint part 26, the lower inner side knee joint part 27 and the lower outer side knee joint part 30, and can be used as energy storage elements to effectively reduce the maximum power required by the driving motor 25 and reduce the energy consumption caused by the vertical gravity fluctuation of the exoskeleton when the exoskeleton drives a human body to move.

As shown in fig. 5, the exoskeleton's ankle joint 3 comprises an ankle coronal axis 31, a vertical posterior ankle joint 32, an ankle transverse portion 33, a vertical anterior ankle joint 34, an ankle torsion spring 35, and an ankle sagittal axis 36. The vertical rear ankle joint 32 and the vertical front ankle joint 34 are arranged in bilateral symmetry and are connected through an ankle joint sagittal plane shaft 36, and the special-shaped nut and the thrust bearing used in the position belong to the same type as those used in the hip joint, and are not described again; the ankle joint transverse part 33 is connected with the sole wheel type driving module 4 through an ankle joint coronal plane shaft 31; the lateral ankle joint portion 33 is configured to resemble the motion of a cross-joint by means of the coronal axis 31 and the sagittal axis 36; ankle torsion springs 35 are arranged between the ankle transverse portion 33 and the vertical front ankle joint 34 and between the ankle transverse portion 33 and the foot wheel type driving module 4 to serve as motion energy storage elements.

The rotational degrees of freedom of the exoskeleton of the invention are 2-1-1, namely, the ankle joint 3 has one rotational degree of freedom in the sagittal plane and the coronal plane respectively, and the knee joint 2 and the hip joint 1 have one rotational degree of freedom in the sagittal plane. The mechanical degree of freedom of the exoskeleton is 6 according to a mechanical degree of freedom calculation formula, namely, the motion state of the exoskeleton can be completely determined by only six drivers.

The knee joint 2 of the invention is an active joint driver, the ankle joint 3 is an unpowered passive joint, and the hip joint 1 can be provided with an active joint driver similar to the knee joint 2 or can change the state of the degree of freedom thereof by using a controllable driver according to the use requirement. When the active joint driver is installed on the hip joint 1, the motion of the hip joint 1 is mutually coupled with the foot wheel type driver and the opposite hip joint driver in the two-foot landing period, the motion decoupling is realized by adopting a mathematical modeling method, and the motion decoupling is realized by adopting a mechanical method in order to simplify a control system and also by adopting a controllable brake to control the rotation state of the hip joint 1. The latter design method of the controllable brake is used in the embodiments disclosed herein, where the controllable brake is preferably an electromagnetic brake in practical implementation.

To enable rapid motion balance in the sagittal plane, the foot of each foot is fitted with a wheeled drive. Each foot has two wheels, wherein the front wheel is an unpowered auxiliary wheel, and the rear wheel is a small-sized hub motor. In order to better adapt to users with different heights, the exoskeleton is provided with adjustable screw holes at the joints of all joints, so that the length of the femur 7 and the tibia 8 can be adjusted. In a practical exoskeleton, flexible straps are designed on the pelvis 5, femur 7, tibia 8 and feet, respectively, to bind the exoskeleton to the upper limbs, thighs and feet of the human body. The devices belonging to the man-machine flexible physical interface are completely removed in the attached drawings of the invention so as to more clearly display the mechanical structure of the exoskeleton.

In order to better compromise weight and strength, the exoskeleton of the present invention uses different preferred materials in different parts to minimize weight. The femur 7 and the tibia 8 are respectively formed by combining two carbon fiber plates through support studs and fixing screws. The pelvis supporting plate 9 is made of a carbon fiber plate, and the other parts of the pelvis 5 except the supporting seat 6 are made of aluminum alloy. The supporting seat 6 is made of high-strength plastic and sponge cloth is arranged at the position contacted with a human body. The whole shells of the hip joint 1, the knee joint 2 and the ankle joint 3 are made of aluminum alloy. The sole driving module 4 is also formed by assembling and combining a plurality of aluminum alloy plates.

It should be noted that the subject to which the exoskeleton is directed is a spinal cord injured patient, because the majority of spinal cord injured patients are among the population with impaired lower limb function. However, other walking aid rehabilitation methods such as hemiplegic patients and cerebral apoplexy patients can also be applied to the exoskeleton. Such object-oriented changes caused by different use populations should not have any impact on the scope of the present invention.

Finally, it should be pointed out that: the above examples are only for illustrating the technical solutions of the present invention, and are not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims

1. A sole wheel type driving self-balancing power exoskeleton for a spinal cord injury patient comprises a hip joint (1), a knee joint (2), an ankle joint (3), a sole driving module (4), a pelvis (5), a femur (7) and a tibia (8), wherein the hip joint (1), the femur (7), the knee joint (2), the tibia (8), the ankle joint (3) and the sole driving module (4) are arranged from top to bottom and are arranged in a bilateral symmetry mode, and the hip joint (1) comprises a hip joint supporting strip (16), a thrust bearing (17), a special-shaped nut (18), an electromagnetic brake fixing screw (19), an inner hip joint (20), an electromagnetic brake (21), an outer hip joint (22), a hip joint belt key shaft (23) and a hip joint fixing screw (24); the left hip joint and the right hip joint (1) are connected through a pelvis (5), the hip joint (1) is connected with a knee joint (2) through a femur (7), the knee joint (2) is connected with an ankle joint (3) through a tibia (8), and the ankle joint (3) is connected with a vola driving module (4), the hip joint rotation pair is formed by screwing the hip joint support strip (16) and a pelvis transverse support (10) into different screw holes through bolts to realize position adjustment, an inner hip joint (20) is connected with an outer hip joint (22) through a hip joint fixing screw (24), an electromagnetic brake (21) is connected with the inner hip joint (20) through an electromagnetic brake fixing screw (19), and the hip joint fixing screw (23) is provided with a flat key, the flat key is matched with a movable part key groove of the electromagnetic brake (21), when the electromagnetic brake (21) is in a non-enabling state, the movable part of the hip joint (1) freely rotates, and when the electromagnetic brake (21) is in an enabling state, the hip joint (1) cannot freely rotate due to braking; the degree of freedom arrangement mode of the exoskeleton is that the hip joint (1) has one degree of freedom of rotation on a sagittal plane, the knee joint (2) has one degree of freedom of rotation on the sagittal plane, and the ankle joint (3) has one degree of freedom of rotation on the sagittal plane and the coronal plane respectively; the knee joint (2) comprises a driving motor (25), a knee joint upper part (26), a lower inner side knee joint (27), a knee joint lower part fixing screw (28), a knee joint torsional spring (29) and a lower outer side knee joint (30), the driving motor (25) is vertically arranged to reduce the whole transverse size, a speed reducer is integrated in the knee joint upper part (26), the lower inner side knee joint (27) and the lower outer side knee joint (30) are arranged in a bilateral symmetry way, the knee joint upper part (26) is connected with the lower inner side knee joint (27) and the lower outer side knee joint (30) through the knee joint lower part fixing screws (28), and the hollow parts connected with the knee joint upper part (26) and the lower inner side knee joint (27) and the lower outer side knee joint (30) are respectively provided with a knee joint torsion spring (29) which is used as an energy storage element of the knee joint (2) to reduce the maximum power required by a driving motor (25) and reduce the energy consumption of vertical gravity fluctuation when; the ankle joint (3) comprises an ankle joint coronal plane shaft (31), a vertical rear side ankle joint (32), an ankle joint transverse part (33), a vertical front side ankle joint (34), an ankle joint torsion spring (35) and an ankle joint sagittal plane shaft (36), the vertical rear side ankle joint (32) and the vertical front side ankle joint (34) are arranged in a left-right symmetrical manner, the ankle joint is connected through an ankle joint sagittal plane shaft (36), an ankle joint transverse part (33) is connected with a sole driving module (4) through an ankle joint coronal plane shaft (31), the ankle joint transverse part (33) is set into an ankle joint movement form of a cross connecting shaft through the ankle joint coronal plane shaft (31) and the ankle joint sagittal plane shaft (36), and ankle joint torsion springs (35) are arranged between the ankle joint transverse part (33) and a vertical front ankle joint (34) and between the ankle joint transverse part (33) and the foot driving module (4) and serve as energy storage elements of the ankle joint (3); the sole drive module (4) comprises a wheel type driver and wheels.

2. An exoskeleton as claimed in claim 1 characterised in that the hip joint (1) is an active joint actuator; the knee joint (2) is an active joint driver and comprises an energy storage element; the ankle joint (3) is an unpowered passive joint and comprises energy storage elements in the sagittal plane and the coronal plane respectively.

3. An exoskeleton as claimed in claim 1 wherein the pelvis (5) includes support means to lift the user from the crotch and transfer the weight of the person from the support means through the exoskeleton to the ground, reducing the weight of the person to which the exoskeleton is required to restrain.

4. An exoskeleton as claimed in claim 1 characterised in that the support means for the pelvis (5) comprise a support base (6), a pelvis support plate (9), a transverse pelvis support (10), a lateral pelvis support (11), a support tube connection (12), a vertical tube (13), a tube connection (14) and a transverse tube (15), the support base (6) being connected to the pelvis support plate (9) via the support tube connection (12), the vertical tube (13), the tube connection (14) and the transverse tube (15), the pelvis support plate (9) being arranged in two front and rear pieces, connected via the lateral pelvis support (11), the hollow parts of which are used for mounting a power supply and an electrical control system, the transverse pelvis support (10) being arranged in a left-right symmetry and connected to the lateral pelvis support (11) via screws, the transverse pelvis support (10) being provided with a plurality of screw holes through which the pelvis (5) can be connected to the hip joint (1), the supporting seat (6) is adjusted in the front-back direction and the up-down direction through a plurality of screw holes arranged on the vertical tube (13) and the horizontal tube (15), and the pelvis (5) can be adjusted in the front-back direction, the up-down direction and the lateral direction through the transverse pelvis support (10) and the lateral pelvis support (11).

5. An exoskeleton as claimed in claim 1 wherein the front wheels of the wheels are unpowered auxiliary wheels and the rear wheels are in-wheel motors.

6. An exoskeleton as claimed in claim 4 characterised in that the hip joint (1), knee joint (2), ankle joint (3) and foot drive module (4) are all made of aluminium alloy, the pelvis (5) is made of aluminium alloy except for the support base (6), the support base (6) is made of high strength plastic and sponge cloth is used in the contact part with the human body, and the femur (7), tibia (8) and pelvis support plate (9) are all made of carbon fibre plate.