CN117064702A - Wearable flexible lower limb gravity balance exoskeleton - Google Patents

Wearable flexible lower limb gravity balance exoskeleton Download PDF

Info

Publication number
CN117064702A
CN117064702A CN202311211538.2A CN202311211538A CN117064702A CN 117064702 A CN117064702 A CN 117064702A CN 202311211538 A CN202311211538 A CN 202311211538A CN 117064702 A CN117064702 A CN 117064702A
Authority
CN
China
Prior art keywords
lower limb
gravity
gravity balance
knee
exoskeleton
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202311211538.2A
Other languages
Chinese (zh)
Inventor
孟巧玲
孙振坤
孔博磊
曾庆鑫
余雷
喻洪流
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
University of Shanghai for Science and Technology
Original Assignee
University of Shanghai for Science and Technology
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by University of Shanghai for Science and Technology filed Critical University of Shanghai for Science and Technology
Priority to CN202311211538.2A priority Critical patent/CN117064702A/en
Publication of CN117064702A publication Critical patent/CN117064702A/en
Pending legal-status Critical Current

Links

Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61H—PHYSICAL THERAPY APPARATUS, e.g. DEVICES FOR LOCATING OR STIMULATING REFLEX POINTS IN THE BODY; ARTIFICIAL RESPIRATION; MASSAGE; BATHING DEVICES FOR SPECIAL THERAPEUTIC OR HYGIENIC PURPOSES OR SPECIFIC PARTS OF THE BODY
    • A61H1/00—Apparatus for passive exercising; Vibrating apparatus ; Chiropractic devices, e.g. body impacting devices, external devices for briefly extending or aligning unbroken bones
    • A61H1/02—Stretching or bending or torsioning apparatus for exercising
    • A61H1/0237—Stretching or bending or torsioning apparatus for exercising for the lower limbs
    • A61H1/0255—Both knee and hip of a patient, e.g. in supine or sitting position, the feet being moved in a plane substantially parallel to the body-symmetrical-plane
    • A61H1/0262—Walking movement; Appliances for aiding disabled persons to walk
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61H—PHYSICAL THERAPY APPARATUS, e.g. DEVICES FOR LOCATING OR STIMULATING REFLEX POINTS IN THE BODY; ARTIFICIAL RESPIRATION; MASSAGE; BATHING DEVICES FOR SPECIAL THERAPEUTIC OR HYGIENIC PURPOSES OR SPECIFIC PARTS OF THE BODY
    • A61H2201/00—Characteristics of apparatus not provided for in the preceding codes
    • A61H2201/14—Special force transmission means, i.e. between the driving means and the interface with the user
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61H—PHYSICAL THERAPY APPARATUS, e.g. DEVICES FOR LOCATING OR STIMULATING REFLEX POINTS IN THE BODY; ARTIFICIAL RESPIRATION; MASSAGE; BATHING DEVICES FOR SPECIAL THERAPEUTIC OR HYGIENIC PURPOSES OR SPECIFIC PARTS OF THE BODY
    • A61H2201/00—Characteristics of apparatus not provided for in the preceding codes
    • A61H2201/16—Physical interface with patient
    • A61H2201/1602—Physical interface with patient kind of interface, e.g. head rest, knee support or lumbar support
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61H—PHYSICAL THERAPY APPARATUS, e.g. DEVICES FOR LOCATING OR STIMULATING REFLEX POINTS IN THE BODY; ARTIFICIAL RESPIRATION; MASSAGE; BATHING DEVICES FOR SPECIAL THERAPEUTIC OR HYGIENIC PURPOSES OR SPECIFIC PARTS OF THE BODY
    • A61H2201/00—Characteristics of apparatus not provided for in the preceding codes
    • A61H2201/16—Physical interface with patient
    • A61H2201/1602—Physical interface with patient kind of interface, e.g. head rest, knee support or lumbar support
    • A61H2201/1614—Shoulder, e.g. for neck stretching
    • A61H2201/1616—Holding means therefor
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61H—PHYSICAL THERAPY APPARATUS, e.g. DEVICES FOR LOCATING OR STIMULATING REFLEX POINTS IN THE BODY; ARTIFICIAL RESPIRATION; MASSAGE; BATHING DEVICES FOR SPECIAL THERAPEUTIC OR HYGIENIC PURPOSES OR SPECIFIC PARTS OF THE BODY
    • A61H2201/00—Characteristics of apparatus not provided for in the preceding codes
    • A61H2201/16—Physical interface with patient
    • A61H2201/1602—Physical interface with patient kind of interface, e.g. head rest, knee support or lumbar support
    • A61H2201/1619—Thorax
    • A61H2201/1621—Holding means therefor
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61H—PHYSICAL THERAPY APPARATUS, e.g. DEVICES FOR LOCATING OR STIMULATING REFLEX POINTS IN THE BODY; ARTIFICIAL RESPIRATION; MASSAGE; BATHING DEVICES FOR SPECIAL THERAPEUTIC OR HYGIENIC PURPOSES OR SPECIFIC PARTS OF THE BODY
    • A61H2201/00—Characteristics of apparatus not provided for in the preceding codes
    • A61H2201/16—Physical interface with patient
    • A61H2201/1602—Physical interface with patient kind of interface, e.g. head rest, knee support or lumbar support
    • A61H2201/164—Feet or leg, e.g. pedal
    • A61H2201/1642—Holding means therefor
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61H—PHYSICAL THERAPY APPARATUS, e.g. DEVICES FOR LOCATING OR STIMULATING REFLEX POINTS IN THE BODY; ARTIFICIAL RESPIRATION; MASSAGE; BATHING DEVICES FOR SPECIAL THERAPEUTIC OR HYGIENIC PURPOSES OR SPECIFIC PARTS OF THE BODY
    • A61H2201/00—Characteristics of apparatus not provided for in the preceding codes
    • A61H2201/16—Physical interface with patient
    • A61H2201/1602—Physical interface with patient kind of interface, e.g. head rest, knee support or lumbar support
    • A61H2201/165—Wearable interfaces
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61H—PHYSICAL THERAPY APPARATUS, e.g. DEVICES FOR LOCATING OR STIMULATING REFLEX POINTS IN THE BODY; ARTIFICIAL RESPIRATION; MASSAGE; BATHING DEVICES FOR SPECIAL THERAPEUTIC OR HYGIENIC PURPOSES OR SPECIFIC PARTS OF THE BODY
    • A61H2205/00—Devices for specific parts of the body
    • A61H2205/10—Leg

Abstract

The invention discloses a wearable flexible lower limb gravity balance exoskeleton, which relates to the field of exoskeleton robots and comprises flexible clothing, a knee joint binding mechanism, a bowden wire transmission mechanism and a gravity balance device, wherein the flexible clothing is worn on the upper half of a human body, a stress anchor point is provided for the gravity balance device, and the wearing stability is ensured; the knee joint binding mechanism is arranged at the knee joint of the lower limb of the human body and connects the gravity balancing device with the knee joint; the bowden wire transmission mechanism is distributed on the front side of the thigh and provides assistance for hip joint buckling, and is connected with the knee joint binding mechanism; the gravity balance device is arranged on the front side of the flexible garment, the hip joint is assisted in buckling, the gravity balance mechanism is combined with the Bowden wire transmission mechanism, and the bionic driving mode is adopted to simulate the trend of the force lines of the hip flexors of the lower limbs. The invention adopts a variable stiffness design, and the elastic element and the flexible mechanism are matched with the motion change of the human body, so that the adaptation degree of the exoskeleton and the human body is higher, and the assistance and the safety are improved.

Description

Wearable flexible lower limb gravity balance exoskeleton
Technical Field
The invention relates to the field of exoskeleton robots, in particular to a wearable flexible lower limb gravity balance exoskeleton.
Background
With the deepening of the degree of Chinese aging, the problems of insufficient muscle strength of lower limbs and the like caused by the physiological function decline seriously affect the activities of daily living of the old. To assist the elderly in walking, some wearable devices have been proposed in which the lower limb exoskeleton has an important role in promoting the patient's return to normal functioning.
Currently, most of the lower limb exoskeletons are of rigid structures, and the weight is generally large, so that the energy consumption of a wearer can be increased as an additional burden. Meanwhile, the rigid structure can limit the freedom degree of joint movement to change the natural gait mode of a wearer, and the flexible lower limb exoskeleton has the advantages of light weight, strong adaptability to human body movement and the like, and is attracting more attention.
Therefore, those skilled in the art have been working on providing a wearable flexible lower limb gravity balance exoskeleton for rehabilitation of lower limb dyskinesia, which meets the requirements of light weight, large flexibility and more natural assistance, and can perform gravity compensation on the hip joint during walking of a person, so as to generate the effect of lower limb gravity balance and reduce the energy consumption of the wearer during walking.
Disclosure of Invention
In view of the above-mentioned drawbacks of the prior art, the present invention aims to solve the technical problem that the rigid structure of the conventional exoskeleton is difficult to adapt to the motion changes of the human body at different stages, and is difficult to adapt to the complex external environment.
In order to achieve the above purpose, the invention provides a wearable flexible lower limb gravity balance exoskeleton, which is characterized in that the wearable flexible lower limb gravity balance exoskeleton is bilaterally symmetrical relative to a human body and comprises a flexible garment, a knee joint binding mechanism, a bowden wire transmission mechanism and a gravity balance device, wherein,
the flexible garment is worn on the upper half of a human body, a stress anchor point is provided for the gravity balancing device, and the wearing stability is ensured;
the knee joint binding mechanism is arranged at the knee joint of the lower limb of the human body and connects the gravity balancing device with the knee joint;
the bowden cable transmission mechanism is distributed on the front side of the thigh and provides assistance for hip joint buckling, and the bowden cable transmission mechanism is connected with the knee joint binding mechanism;
the gravity balance device is arranged on the front side of the flexible garment and used for assisting in buckling of the hip joint, the gravity balance mechanism is combined with the Bowden wire transmission mechanism, and a bionic driving mode is adopted to simulate the trend of the force line of the hip flexor of the lower limb.
Further, the flexible clothing includes two baldric, chest fixed band, waist fixed band and waistband, the both shoulders area with chest fixed band fixed connection, the waist fixed band with waistband fixed connection guarantees when providing stable anchor point flexible clothing is closely with the laminating of human upper body.
Further, the knee joint binding mechanism comprises a knee upper part, a knee middle part and a knee lower part, wherein the knee upper part and the knee lower part are composed of a low-temperature thermoplastic plate and a sponge lining, the knee middle part comprises a supporting spring, two ends of the knee middle part are respectively connected with the knee upper part and the low-temperature thermoplastic plate of the knee lower part, the wearing comfort is improved while the firmness is ensured, and the knee upper part is connected with the lower end of a bowden wire in the bowden wire transmission mechanism.
Further, the gravity balancing device comprises a fixed group module and a sliding group module, wherein the fixed group module comprises a waist fixing shell, a guide rod fixing plate and a sliding fixing piece, the sliding group module comprises a sliding plate, a guide rod, a spring, a guide pulley, a screw rod, a rack and a hole pressing plate, the sliding plate of the sliding group module is used for fixing parts of the gravity balancing device, the sliding plate is embedded with holes on two sides of the waist fixing shell, and the number of the sliding fixing piece is identical with that of the guide pulley, and is three.
Further, the guide pulley is fixed on the outer side of the sliding plate by the sliding fixing piece through a bolt and is used for defining a transmission path for the Bowden wire; the gear transmission plate is embedded into the upper part of the sliding plate and used for fixing the inner side mechanism; the gear wire axle inside the sliding plate connects two gears and one wire wheel with the gear transmission piece for tightening or stretching the bowden cable when driving.
Further, the upper end of the guide rod is connected with the guide rod fixing plate through a bolt, the hole pressing plate is provided with three holes, the holes penetrate through two guide rods and one screw rod respectively, two springs are sleeved on the two guide rods respectively, and a compression path is defined for the springs.
Further, two racks fixed on the inner side of the waist fixing shell are used for being meshed with the gear, and the sliding plate is driven to slide up and down through rotation of the gear when the spring is compressed or relaxed.
Further, the wearable flexible lower limb gravity balance exoskeleton adopts the spring as an elastic element, and the lead screw is used for adjusting the precompression amount of the elastic element, so that the system rigidity change of the whole mechanism is realized; when the lower limb of the human body swings, the knee joint binding mechanism transmits force to the gravity balancing device of the waist through the Bowden wire transmission mechanism, the sliding plate starts sliding through the rotation of the gear on the rack and starts compressing the elastic element under the condition of stress, and the screw rod mechanism changes the system rigidity of the whole mechanism through changing the precompression amount, so that the gravity balance of the lower limb is achieved.
Further, the gravity balancing device adopts a spring auxiliary method to offset the influence of gravity, the spring auxiliary method does not add undue weight, the rigidity of a system is changed by rotating the screw rod to change the precompression amount of the spring, the gravity moment generated by the lower limb during walking is compensated, the spring auxiliary method utilizes the energy stored by the compression of the spring to additionally increase elastic potential energy, the human body and the gravity balancing device are mutually matched, and the elastic potential energy is stored to ensure that the hip joint moment and the leg gravity moment are equal to achieve gravity balance.
Further, the hip joint moment M h The method comprises the following steps:
M h ＝K h ×(l-l 0 )×L h
wherein K is h Is the spring rate, l is the spring length, l 0 For the initial length of the spring L h A moment arm which is a spring opposite to the rotation center of the hip joint;
the leg weight moment M born by the hip joint in the process of buckling and lifting of the lower limb of the human body G The method comprises the following steps:
M G ＝m 1 gl 1 * sinθ h +m 2 g(l 1 sinθ h +l 2 * sin(θ h -θ k ))+m 3 g(l 1 sinθ h +l 2 sin(θ h -θ k ))
wherein, the rotation center of the hip joint is taken as the origin of coordinates, l 1 Length of thigh, m 1 The thigh mass is the distance from the center of mass of the thigh to the rotation center of the hip joint is l 1 * ，l 2 For the length of the lower leg, m 2 The distance from the center of mass of the shank to the rotation center of the knee joint is l as the shank mass 2 * ，m 3 For the purpose of simplifying the foot to a mass point at the end of the shank, theta h Is the rotation angle of the hip joint, theta k Is the rotation angle of the knee joint;
according to the static gravity balance model of the lower limb of the human body, when M g ＝M h When a weight moment balance is achieved, the stiffness K of the weight balancing device h The method comprises the following steps:
wherein θ 1 、θ 2 、d 3 、h 3 The method can be calculated by the following formula:
wherein d 1 Is from point U h To P hip D is the vertical distance of 2 Is from point U h To P hip Horizontal distance between h 1 From point H to point P hip Distance, h 2 Representation point D h And H; point P hip Upper anchor point U as the rotation center of hip joint h Is arranged on the upper forehead spine and the lower anchor point D h Is arranged on the body surface of the front side of thigh, half the length of femur, U h D h P hip The plane is parallel to sagittal plane of human body and the point P is point U h Projection on human torso, point H is point D h Projection on the mid-thigh axis.
In the preferred embodiment of the invention, compared with the prior art, the invention has the following specific beneficial effects:
1. the invention adopts a variable stiffness design, the elastic element is matched with the flexible mechanism, and provides proper stiffness and shape to match the motion change of the human body at different stages, thereby better adapting to the rehabilitation requirement of the patient, adjusting the stiffness according to the actual situation and having higher assistance and safety.
2. The invention adopts modularized design, has smaller parts, simple structure and convenient assembly, combines the gravity balance mechanism and the Bowden wire transmission mechanism, adopts a bionic driving mode to simulate the trend of the force lines of the hip flexors of the lower limbs, improves the transmission efficiency and reduces the metabolism cost of a wearer in the movement process.
3. According to the invention, the rigid connecting rod is replaced by the flexible binding bands, each binding band is mutually sewed and is provided with the fixing buckle, so that the waist binding band is convenient to put on and take off, is used as a stress point of the gravity balance mechanism, is more fit for a human body, provides a stable stress anchor point on the basis of ensuring firmness, is more convenient to wear, has better comfortableness, and can be suitable for different body types.
The conception, specific structure, and technical effects of the present invention will be further described with reference to the accompanying drawings to fully understand the objects, features, and effects of the present invention.
Drawings
FIG. 1 is a schematic illustration of the wearing effect provided by a preferred embodiment of the present invention;
FIG. 2 is a schematic view of a flexible garment constructed in accordance with a preferred embodiment of the present invention;
FIG. 3 is a schematic view of a knee joint binding mechanism provided by a preferred embodiment of the present invention;
FIG. 4 is a schematic view of the overall structure of a gravity balancing device according to a preferred embodiment of the present invention;
FIG. 5 is a schematic view showing the internal structure of a gravity balancing device according to a preferred embodiment of the present invention;
FIG. 6 is a schematic view of the outside of a slide plate of a gravity balance device according to a preferred embodiment of the present invention;
FIG. 7 is a schematic view of the inside of a sliding plate of a gravity balance device according to a preferred embodiment of the present invention;
FIG. 8 is a schematic view of a sliding set of a gravity balance device according to a preferred embodiment of the present invention;
FIG. 9 is a schematic view of the inside of a waist fixing case of a gravity balance device according to a preferred embodiment of the present invention;
FIG. 10 is a mathematical model of a human lower limb hip joint provided by a preferred embodiment of the present invention;
FIG. 11 is a diagram of a static gravity balance model of a human lower limb provided by a preferred embodiment of the present invention;
fig. 12 is a dynamic gravity balance model of a human lower limb according to a preferred embodiment of the present invention.
In the drawing the view of the figure,
1-flexible clothing, 101-double shoulder straps, 102-chest fixation straps, 103-waist fixation straps, 104-waist straps,
2-knee joint binding mechanism, 201-upper knee, 202-middle knee, 203-lower knee,
a 3-Bowden wire transmission mechanism, 301-Bowden wire,
4-gravity balancing device, 401-fixed group module, 4011-waist fixed shell, 4012-guide rod fixed plate, 4013-sliding fixed piece, 402-sliding group module, 4021-sliding plate, 40211-wire wheel, 40212-gear, 40213-gear wire wheel shaft, 40214-gear transmission plate, 4022-guide rod, 4023-spring, 4024-guide pulley, 4025-screw rod, 4026-rack and 4027-hole pressing plate.
Detailed Description
The following description of the preferred embodiments of the present invention refers to the accompanying drawings, which make the technical contents thereof more clear and easy to understand. The present invention may be embodied in many different forms of embodiments and the scope of the present invention is not limited to only the embodiments described herein.
In the drawings, like structural elements are referred to by like reference numerals and components having similar structure or function are referred to by like reference numerals. The dimensions and thickness of each component shown in the drawings are arbitrarily shown, and the present invention is not limited to the dimensions and thickness of each component. The thickness of the components is exaggerated in some places in the drawings for clarity of illustration.
As shown in fig. 1, the wearable flexible lower limb gravity balance exoskeleton provided by the embodiment of the invention can be used for rehabilitation of lower limb movement dysfunction, meets the requirements of light weight, large flexibility and more natural assistance, can perform gravity compensation on hip joints in the walking process of a person, generates the effect of lower limb gravity balance, reduces the energy consumption of the wearer in the walking process, is bilaterally symmetrical relative to a human body, comprises a flexible garment 1, a knee joint binding mechanism 2, a bowden line transmission mechanism 3 and a gravity balance device 4, wherein,
the flexible garment 1 is worn on the upper half of a human body, a stress anchor point is provided for a gravity balance device, and the wearing stability is ensured;
the knee joint binding mechanism 2 is arranged at the knee joint of the lower limb of the human body and connects the gravity balancing device 4 with the knee joint;
the Bowden wire transmission mechanism 3 is distributed on the front side of the thigh, and provides assistance for hip joint buckling, and the Bowden wire transmission mechanism 3 is connected with the knee joint binding mechanism 2;
the gravity balance device 4 is arranged on the front side of the flexible garment 1, the hip joint is assisted in buckling, the gravity balance mechanism 4 is combined with the Bowden wire transmission mechanism 3, and the bionic driving mode is adopted to simulate the force line trend of the hip flexor of the lower limb.
As shown in fig. 2, the flexible garment 1 includes a double shoulder strap 101, a chest fixing strap 102, a waist fixing strap 103 and a waistband 104, the double shoulder strap 101 is fixedly connected with the chest fixing strap 103, the waist fixing strap 104 is fixedly connected with the waistband 104, and the flexible garment 1 is tightly attached to the upper half body of a human body while providing a stable anchor point.
Preferably, the both shoulder straps 101 are sewn to the chest strap 103, and the waist strap 104 is sewn to the waist strap 104.
As shown in fig. 3, the knee joint tying mechanism 2 comprises a knee upper part 201, a knee middle part 202 and a knee lower part 203, wherein the knee upper part 201 and the knee lower part 203 are composed of a low-temperature thermoplastic plate and a sponge lining, the knee middle part 202 comprises a supporting spring, two ends of the knee middle part 202 are respectively connected with the low-temperature thermoplastic plate of the knee upper part 201 and the knee lower part 203, the firmness is ensured, and meanwhile, the wearing comfort is improved, and the knee upper part 201 is connected with the lower end of a 3 bowden wire 301 in the bowden wire transmission mechanism.
As shown in fig. 4 to 9, the gravity balancing device 4 includes a fixed group module 401 and a sliding group module 402, the fixed group module 401 includes a waist fixing shell 4011, a guide rod fixing plate 4012 and a sliding fixing piece 4013, the sliding group module 402 includes a sliding plate 4021, a guide rod 4022, a spring 4023, a guide pulley 4024, a screw rod 4025, a rack 4026 and a hole pressing plate 4027, the sliding plate 4021 of the sliding group module 402 is used for fixing parts of the gravity balancing device 4, the sliding plate 4021 is embedded with holes on two sides of the waist fixing shell 4011, the number of the sliding fixing piece 4013 and the guide pulley 4024 is the same, and the number is set into three groups. The guide pulley 2024 is fixed to the outside of the sliding plate 4021 by a slide fixing member 4013 by bolts for defining a transmission path for the bowden cable 301; the gear transmission plate 40214 is embedded in the upper part of the sliding plate 4021 and is used for fixing the inner mechanism; a gear wheel axle 40213 inside the sliding plate 4021 connects the two gears 40212 and one wire wheel 40211 with a gear transmission piece 40214 for tightening or stretching the bowden cable 301 when driving. The upper end of the guide rod 4022 is connected with the guide rod fixing plate 4012 through bolts, the hole pressing plate 4027 is provided with three holes, the holes penetrate through the two guide rods 4022 and the screw rod 4025 respectively, the two guide rods 4022 are sleeved with two springs 4023 respectively, and a compression path is defined by the springs 4023. Two racks 4026 fixed inside the waist fixing case 4011 are used for being meshed with a gear 40212, and the sliding plate 4021 is driven to slide up and down by rotation of the gear 40212 when the spring 4023 compresses or expands.
The wearable flexible lower limb gravity balance exoskeleton adopts a spring 4023 as an elastic element, and a screw rod 4025 is used for adjusting the precompression amount of the elastic element, so that the system rigidity change of the whole mechanism is realized; when the lower limb of the human body swings, the knee joint binding mechanism 2 transmits force to the gravity balance device 4 of the waist through the transmission mechanism of the Bowden wire 301, the gravity balance device 4 starts sliding through the rotation of the gear 40212 on the rack 4026 under the condition of stress, the elastic element starts to be compressed, and the screw rod mechanism changes the system rigidity of the whole mechanism through changing the precompression amount, so that the effect of balancing the lower limb gravity is achieved.
The gravity balancing device 4 adopts a spring auxiliary method to offset the influence of gravity, the spring auxiliary method does not add undue weight, the precompression amount of the spring 4023 is changed by rotating the screw rod 4025 to change the rigidity of the system, the gravity moment generated by the lower limb during walking is compensated, the spring auxiliary method utilizes the spring 4023 to compress the stored energy, the elastic potential energy is additionally added, the human body and the gravity balancing device 4 are mutually matched, the stored elastic potential energy ensures that the hip joint moment is equal to the leg gravity moment to achieve the gravity balancing effect, wherein,
moment M of hip joint h The method comprises the following steps:
M h ＝K h ×(l-l 0 )×L h
wherein K is h Is the spring rate, l is the spring length, l 0 For the initial length of the spring L h A moment arm which is a spring opposite to the rotation center of the hip joint;
the leg weight moment M born by the hip joint in the process of buckling and lifting of the lower limb of the human body G The method comprises the following steps:
M G ＝m 1 gl 1 * sinθ h +m 2 g(l 1 sinθ h +l 2 *sin(θ h -θ k ))+m 3 g(l 1 sinθ h +l 2 sin(θ h -θ k ))
wherein, the rotation center of the hip joint is taken as the origin of coordinates, l 1 Length of thigh, m 1 The thigh mass is the distance from the center of mass of the thigh to the rotation center of the hip joint is l 1 * ，l 2 For the length of the lower leg, m 2 The distance from the center of mass of the shank to the rotation center of the knee joint is l as the shank mass 2 * ，m 3 For the purpose of simplifying the foot to a mass point at the end of the shank, theta h Is the rotation angle of the hip joint, theta k Is the rotation angle of the knee joint;
according to the static gravity balance model of the lower limb of the human body, when M g ＝M h When a weight moment balance is achieved, the stiffness K of the weight balancing device h The method comprises the following steps:
wherein θ 1 、θ 2 、d 3 、h 3 The method can be calculated by the following formula:
wherein d 1 Is from point U h To P hip D is the vertical distance of 2 Is from point U h To P hip Horizontal distance between h 1 From point H to point P hip Distance, h 2 Representation point D h And H; point P hip Upper anchor point U as the rotation center of hip joint h Is arranged on the upper forehead spine and the lower anchor point D h Is arranged on the body surface of the front side of thigh, half the length of femur, U h D h P hip The plane is parallel to sagittal plane of human body and the point P is point U h Projection on human torso, point H is point D h The projection onto the thigh axis is shown in fig. 10.
Aiming at the problems that the rigid structure of the traditional exoskeleton is difficult to adapt to the motion change of a human body in different stages and difficult to adapt to the complex external environment, the invention adopts a variable stiffness design, and the elastic element is matched with the flexible mechanism to provide proper stiffness and shape to match the motion change of the human body in different stages, so that the invention better adapts to the rehabilitation requirement of a patient. The rigidity is adjusted according to actual conditions, and the safety is higher. The wearable flexible lower limb gravity balance exoskeleton provided by the invention is provided with a line driving mechanism to realize assistance in the lower limb buckling process, realizes the principle design of the lower limb gravity balance mechanism applied to the hip joint by a spring, a gear and a rope driving mode, establishes a kinematics and dynamics model of the lower limb of a human body, analyzes and solves the moment conditions of each joint under the assistance of gravity balance in the gait process, deduces a gravity balance model conforming to the walking of the lower limb of the human body, and can realize the gravity balance of the lower limb in the walking process. According to the invention, the human dynamics and kinematic factors are accurately simulated through strict theoretical calculation, so that the exoskeleton structure is helped to be optimized, the adaptation degree of the exoskeleton and the human body is higher, and the assistance and safety of the exoskeleton are improved.
In addition, aiming at the problems that the existing exoskeleton structure is large in size and mass, and the energy consumption of a wearer can be increased as an extra burden, the invention adopts a modularized design, and has the advantages of small parts, simple structure and convenience in assembly. The gravity balance mechanism is combined with the Bowden wire transmission mechanism, a bionic driving mode is adopted, the force line trend of the lower limb hip flexor is simulated, the transmission efficiency is improved, and the metabolism cost of a wearer in the movement process is reduced. The gravity balancing device mainly comprises a sliding group module and a fixed group module, wherein the device is fixed on a waist binding belt through the fixed group module, a gear and a rack are matched with a sliding plate to slide in the device, the upper end of a Bowden wire transmission mechanism is connected with an internal gear of the device, and the lower end of the Bowden wire transmission mechanism is connected with the upper part of a knee joint binding mechanism. When the lower limb of the human body swings, the knee joint binding mechanism transmits force to the gravity balancing device of the waist through the Bowden wire transmission mechanism, the sliding plate starts to slide through the rotation of the gear on the rack under the condition of stress, the elastic element starts to be compressed, and at the moment, the screw rod mechanism can change the system rigidity of the whole mechanism through changing the precompression amount, so that the effect of balancing the lower limb gravity is achieved. Meanwhile, the gravity balancing device provided by the embodiment of the invention has the advantages of small mass, small volume, simple structure of each module and low cost.
Aiming at the problems that the existing exoskeleton is of a rigid structure, cannot be well attached to a human body, and the wearing comfort is poor, and the normal gait of a wearer can be influenced, the invention adopts the flexible binding bands to replace the rigid connecting rods, each binding band is mutually sewed and is provided with the fixing buckle to be convenient to wear and take off, the waist binding band is used as a stress point of a gravity balance mechanism, the force of the flexible garment is uniformly dispersed to the upper half body of the human body through the stress point of the waistband, the knee joint binding mechanism is divided into an upper part, a middle part and a lower part, namely, the stress point of the lower limb is better fixed, the knee joint is protected, the mechanism cannot deviate under the action of force, the flexible binding band is more attached to the human body, a stable stress anchor point is provided on the basis of ensuring the firmness, the wearing is more convenient, the comfort is better, and the knee joint binding mechanism can adapt to different types.
The present invention will be described in detail with reference to preferred embodiments thereof.
The wearable flexible lower limb gravity balance exoskeleton provided by the preferred embodiment of the invention comprises a flexible garment 1, a knee joint binding mechanism 2, a bowden wire transmission mechanism 3 and a gravity balance device 4, wherein the wearing effect is shown in figure 1.
The flexible garment 1 is worn on the upper half of a human body, a stress anchor point is provided for the gravity balancing device 4, and the wearing stability is ensured; the knee joint binding mechanism 2 is arranged at the knee joint of the lower limb of the human body and is used for connecting the gravity balancing device 4 with the knee joint; the Bowden wire transmission mechanism 3 is distributed on the front side of the thigh to provide assistance for hip joint flexion; a gravity balance device 4 is arranged on the front side of the flexible garment 1 to assist in hip joint flexion. The invention provides auxiliary torque for the buckling of the hip joint under the unsynchronized phase of a wearer, achieves the effect of gravity balance of the lower limb by changing the spring stiffness to perform gravity compensation on the hip joint, improves the walking stability of the person with lower limb dysfunction, and improves the abnormal gait of the lower limb.
The wearable flexible lower limb gravity balance exoskeleton of this embodiment is bilaterally symmetrical with respect to the human body, and only a unilateral structure will be described below unless otherwise specified.
As shown in fig. 2, the flexible garment 1 includes a double shoulder strap 101, a chest strap 102, a waist strap 103, and a waist belt 104, the double shoulder strap 101 being sewn to the chest strap 102, the waist strap 103 being sewn to the waist belt 104. The flexible garment 1 is tightly attached to the upper body of the human body while providing a stable anchor point.
As shown in fig. 3, the knee joint tying mechanism 2 comprises a knee upper part 201, a knee middle part 202 and a knee lower part 203, wherein the knee upper part 201 and the knee lower part 203 are respectively composed of a low-temperature thermoplastic plate and a sponge lining, the knee middle part 202 comprises a supporting spring, and two ends of the supporting spring are respectively connected with the low-temperature thermoplastic plates of the knee upper part 202 and the knee lower part 203, so that the firmness is ensured and the wearing comfort is improved. The lower end of the bowden cable 301 is connected to the laptop 201.
As shown in fig. 4 and 5, the fixed group module 401 and the sliding group module 402 are connected by respective parts, wherein the main parts are fixed on the sliding plate 4021, and the sliding plate 4021 is engaged with holes on both sides of the waist fixing case 4011 to constitute the whole gravity balance device 4.
As shown in fig. 6 and 7, three guide pulleys 4024 are bolted to the outside of the sliding plate 4021 by three sets of sliding fixtures 4013 for defining the transmission path for the bowden cable 301. And a gear transmission plate 40214 is embedded in an upper portion of the sliding plate 4021 for fixing the inside mechanism. The inside gear wire axle 40213 of the sliding plate 4021 connects the two gears 40212 and one wire wheel 40211 with the gear transmission piece 40214 for tightening or stretching the bowden wire when driving.
As shown in fig. 8, the upper end of guide bar 4022 is connected to guide bar fixing plate 4012 by a bolt. The platen 4026 has three holes that pass through two guide rods 4022 and a screw 4025, respectively. Two springs 4023 are respectively sleeved on the two guide rods 4022, and a compression path is defined for the springs 4023.
As shown in fig. 9, two racks 4026 fixed inside the waist fixing case 4011 are used to engage with a gear 40212, and the sliding plate 4021 is driven to slide up and down by rotation of the gear 40212 when the spring is compressed or relaxed.
The gravity balance device adopts a spring-assisted method to offset the influence of gravity by utilizing the energy stored by the compression of the spring, and the spring-assisted method does not add undue weight to the system, and the system changes the rigidity of the system by changing the precompression amount of the spring by rotating the screw rod so as to compensate the gravity moment generated by the lower limb when walking.
The kinetic energy and potential energy of the lower limbs are mutually converted to save the metabolic consumption of the human body in the walking process, and the gravity balancing device additionally increases the elastic potential energy. In the process of stretching backwards from standing to legs, the movement of the lower limbs of the human body stores energy for the springs, and when the lower limbs stretch to a maximum angle, the elastic potential energy reaches the maximum value; with the forward swing of the legs, the gravitational potential energy gradually becomes zero, and the elastic potential energy stored in the human body is partially converted into kinetic energy; in the process of the swing leg buckling lifting, the spring stiffness in the gravity balance device is increased, and when the swing leg buckling lifting reaches the highest position, the elastic potential energy and the kinetic energy stored by the device are all converted into gravitational potential energy. In the whole walking process, the human body and the device are mutually matched, and the elastic potential energy is stored to ensure that the moment of the hip joint is equal to the moment of the leg to achieve the effect of gravity balance.
For the hip exoskeleton mathematical model, K is shown in FIG. 10 h Regarded as the stiffness coefficient of the spring, l is the length of the spring, l 0 For the initial length of the spring, L h Moment M generated by the hip joint is the moment arm of the spring relative to the rotation center of the hip joint h Is that
M h ＝K h ×(l-l 0 )×L h
For the human lower limb static gravity balance model, the leg is regarded as a two-degree-of-freedom mechanism as shown in fig. 11, the rotation center of the hip joint is taken as the origin of coordinates, and the thigh length is l 1 Mass is m 1 The distance from the center of mass to the rotation center of the hip joint is l 1 * . Length of lower leg is l 2 Mass is m 2 The distance from the center of mass to the knee joint rotation center is l 2 * . Simplifying the foot into the tail end of the shank with a mass m 3 Is omitted, only the rotation angles of the hip joint and the knee joint are considered. Leg gravity moment M born by hip joint in buckling and lifting process of lower limb of human body G The method comprises the following steps:
M G ＝m 1 gl 1 * sinθ h +m 2 g(l 1 sinθ h +l 2 * sin(θ h -θ k ))+m 3 g(l 1 sinθ h +l 2 sin(θ h -θ k ))
let M g ＝M h When the gravity balance system is used, the gravity moment balance can be realized, and the rigidity of the gravity balance system is K h ：
Wherein θ 1 、θ 2 、d 3 、h 3 The method can be calculated by the following formula:
wherein d 1 Is from point U h To P hip D is the vertical distance of 2 Is from point U h To P hip Horizontal distance between h 1 From point H to point P hip Distance, h 2 Representation point D h And H; point P hip Upper anchor point U as the rotation center of hip joint h Is arranged on the upper forehead spine and the lower anchor point D h Is arranged on the body surface of the front side of thigh, half the length of femur, U h D h P hip The plane is parallel to sagittal plane of human body and the point P is point U h Projection on human torso, point H is point D h The projection onto the thigh axis is shown in fig. 10.
For the dynamic gravity balance model of the lower limb of the human body, as shown in fig. 12, the potential energy and the kinetic energy of the lower limb of the human body are mutually converted, so that the energy consumption of the human body is further saved. When the spring is added into the lower limb system, elastic potential energy is additionally added to the potential energy.
The rotation center of the hip joint is taken as a zero potential energy position, in the process of swinging leg movement, the human body joint is assumed to do no work any more, the swinging starts to be a position a, the elastic potential energy is set to be the maximum value, the gravitational potential energy is set to be the initial value of the hip joint buckling in the swinging period, and the kinetic energy is set to be zero. When the leg reaches the b position, the gravitational potential energy is set to be 0, the kinetic energy reaches the maximum value, and the elastic potential energy is partially converted into the kinetic energy. When the leg reaches the position c, the gravitational potential energy reaches the maximum value, the elastic potential energy is zero, and the kinetic energy is also zero, so that the elastic potential energy and the kinetic energy are all converted into gravitational potential energy at the moment, the swing leg is buckled and lifted to the highest position, and the maximum elastic potential energy of the auxiliary spring is equal to the gravitational potential energy change amount from the position c to the position a.
The working principle of the wearable flexible lower limb gravity balance exoskeleton of the invention is as follows:
the whole mechanism adopts a spring 4023 as an elastic element, and a screw rod 4025 is used for adjusting the precompression amount of the elastic element, so that the system rigidity change of the whole mechanism is realized. When the lower limb of the human body swings, the knee joint binding mechanism 2 transmits force to the gravity balance device 1 of the waist through the Bowden wire transmission mechanism 3, the device starts to slide under the rotation of the sliding plate 4021 on the rack 4026 through the gear 40212 under the condition of stress, and starts to compress the elastic element, and at the moment, the screw rod mechanism can change the system rigidity of the whole mechanism through changing the precompression amount, so that the effect of balancing the lower limb gravity is achieved.
The foregoing describes in detail preferred embodiments of the present invention. It should be understood that numerous modifications and variations can be made in accordance with the concepts of the invention without requiring creative effort by one of ordinary skill in the art. Therefore, all technical solutions which can be obtained by logic analysis, reasoning or limited experiments based on the prior art by the person skilled in the art according to the inventive concept shall be within the scope of protection defined by the claims.

Claims (10)

1. A wearable flexible lower limb gravity balance exoskeleton is characterized in that the wearable flexible lower limb gravity balance exoskeleton is bilaterally symmetrical relative to a human body and comprises a flexible garment, a knee joint binding mechanism, a Bowden wire transmission mechanism and a gravity balance device, wherein,
the flexible garment is worn on the upper half of a human body, a stress anchor point is provided for the gravity balancing device, and the wearing stability is ensured;
the knee joint binding mechanism is arranged at the knee joint of the lower limb of the human body and connects the gravity balancing device with the knee joint;
the bowden cable transmission mechanism is distributed on the front side of the thigh and provides assistance for hip joint buckling, and the bowden cable transmission mechanism is connected with the knee joint binding mechanism;
the gravity balance device is arranged on the front side of the flexible garment and used for assisting in buckling of the hip joint, the gravity balance mechanism is combined with the Bowden wire transmission mechanism, and a bionic driving mode is adopted to simulate the trend of the force line of the hip flexor of the lower limb.
2. The wearable flexible lower limb gravity balanced exoskeleton of claim 1, wherein the flexible garment comprises a double shoulder strap, a chest strap, a waist strap, and a waistband, wherein the double shoulder strap is fixedly connected with the chest strap, wherein the waist strap is fixedly connected with the waistband, and wherein the flexible garment is secured to the upper body of the human body while providing a stable anchor point.
3. The wearable flexible lower limb gravity balance exoskeleton of claim 1 wherein said knee joint binding mechanism comprises a knee upper portion, a knee middle portion and a knee lower portion, said knee upper portion and said knee lower portion are comprised of a low temperature thermoplastic plate and a sponge liner, said knee middle portion comprises a support spring, two ends of said knee middle portion are respectively connected to said low temperature thermoplastic plate of said knee upper portion and said knee lower portion, ensuring firmness while improving wearing comfort, said knee upper portion is connected to the lower end of a bowden cable in said bowden cable transmission mechanism.
4. The wearable flexible lower limb gravity balance exoskeleton of claim 1, wherein the gravity balance device comprises a fixed group module and a sliding group module, the fixed group module comprises a waist fixing shell, a guide rod fixing plate and a sliding fixing piece, the sliding group module comprises a sliding plate, a guide rod, a spring, a guide pulley, a screw rod, a rack and a hole pressing plate, the sliding plate of the sliding group module is used for fixing parts of the gravity balance device, the sliding plate is embedded with holes on two sides of the waist fixing shell, the sliding fixing piece and the guide pulley are identical in number, and the sliding fixing piece and the guide pulley are all three groups.
5. The wearable flexible lower limb gravity balanced exoskeleton of claim 4 wherein said guide pulley is bolted to the outside of said sliding plate by said sliding fixture for defining a transmission path for said bowden cable; the gear transmission plate is embedded into the upper part of the sliding plate and used for fixing the inner side mechanism; the gear wire axle inside the sliding plate connects two gears and one wire wheel with the gear transmission piece for tightening or stretching the bowden cable when driving.
6. The wearable flexible lower limb gravity balance exoskeleton of claim 5, wherein the upper end of the guide rod is connected with the guide rod fixing plate through a bolt, the hole pressing plate is provided with three holes, the holes respectively penetrate through two guide rods and one screw rod, and the two guide rods are respectively sleeved with two springs, so that a compression path is defined for the springs.
7. The wearable flexible lower limb gravity balance exoskeleton of claim 6, wherein two racks fixed inside the waist fixing case are used for being meshed with the gear, and the sliding plate is driven to slide up and down by rotation of the gear when the spring is compressed or relaxed.
8. The wearable flexible lower limb gravity balance exoskeleton of claim 7 wherein the wearable flexible lower limb gravity balance exoskeleton employs the spring as an elastic element and uses the lead screw to adjust the amount of precompression of the elastic element to achieve a change in system stiffness of the overall mechanism; when the lower limb of the human body swings, the knee joint binding mechanism transmits force to the gravity balancing device of the waist through the Bowden wire transmission mechanism, the sliding plate starts sliding through the rotation of the gear on the rack and starts compressing the elastic element under the condition of stress, and the screw rod mechanism changes the system rigidity of the whole mechanism through changing the precompression amount, so that the gravity balance of the lower limb is achieved.
9. The wearable flexible lower limb gravity balance exoskeleton of claim 8, wherein the gravity balance device adopts a spring-assisted method to counteract the influence of gravity, the spring-assisted method does not add undue weight, the stiffness of the system is changed by rotating the screw rod to change the precompression amount of the spring so as to compensate the gravity moment generated by the lower limb when walking, the spring-assisted method utilizes the spring to compress the stored energy, elastic potential energy is additionally added, the human body and the gravity balance device are mutually matched, and the stored elastic potential energy ensures that the hip joint moment and the leg gravity moment are equal to achieve gravity balance.
10. The wearable flexible lower limb gravity balanced exoskeleton of claim 9 wherein said hip joint moment M h The method comprises the following steps:
M h ＝K h ×(l-l 0 )×L h
wherein K is h Is the spring rate, l is the spring length, l 0 For the initial length of the spring L h A moment arm which is a spring opposite to the rotation center of the hip joint;
the leg weight moment M born by the hip joint in the process of buckling and lifting of the lower limb of the human body G The method comprises the following steps:
M G ＝m 1 gl 1 * sinθ h +m 2 g(l 1 sinθ h +l 2 * sin(θ h -θ k ))+m 3 g(l 1 sinθ h +l 2 sin(θ h -θ k ))
wherein, the rotation center of the hip joint is taken as the origin of coordinates, l 1 Length of thigh, m 1 The thigh mass is the distance from the center of mass of the thigh to the rotation center of the hip joint is l 1 * ，l 2 For the length of the lower leg，m 2 The distance from the center of mass of the shank to the rotation center of the knee joint is l as the shank mass 2 * ，m 3 For the purpose of simplifying the foot to a mass point at the end of the shank, theta h Is the rotation angle of the hip joint, theta k Is the rotation angle of the knee joint;
according to the static gravity balance model of the lower limb of the human body, when M g ＝M h When a weight moment balance is achieved, the stiffness K of the weight balancing device h The method comprises the following steps:
wherein θ 1 、θ 2 、d 3 、h 3 The method can be calculated by the following formula:
wherein d 1 Is from point U h To P hip D is the vertical distance of 2 Is from point U h To P hip Horizontal distance between h 1 From point H to point P hip Distance, h 2 Representation point D h And H; point P hip Upper anchor point U as the rotation center of hip joint h Is arranged on the upper forehead spine and the lower anchor point D h Is arranged on the body surface of the front side of thigh, half the length of femur, U h D h P hip The plane is parallel to sagittal plane of human body and the point P is point U h Projection on human torso, point H is point D h Projection on the mid-thigh axis.
CN202311211538.2A 2023-09-19 2023-09-19 Wearable flexible lower limb gravity balance exoskeleton Pending CN117064702A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202311211538.2A CN117064702A (en) 2023-09-19 2023-09-19 Wearable flexible lower limb gravity balance exoskeleton

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202311211538.2A CN117064702A (en) 2023-09-19 2023-09-19 Wearable flexible lower limb gravity balance exoskeleton

Publications (1)

Publication Number Publication Date
CN117064702A true CN117064702A (en) 2023-11-17

Family

ID=88702484

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202311211538.2A Pending CN117064702A (en) 2023-09-19 2023-09-19 Wearable flexible lower limb gravity balance exoskeleton

Country Status (1)

Country Link
CN (1) CN117064702A (en)

Similar Documents

Publication Publication Date Title
CN109454632B (en) Lower limb exoskeleton system with descending buffer function
CN107811805B (en) Wearable lower limb exoskeleton rehabilitation robot
CN109223456B (en) Lower limb exoskeleton robot system based on man-machine terminal interaction
CN107411939B (en) A kind of dedicated power-assisted healing robot of single lower limb individuals with disabilities
CN209966958U (en) Lower limb exoskeleton assistance rehabilitation device
CN108095976B (en) Bionic knee joint rehabilitation training device with passive rebound function
CN107773384A (en) A kind of variation rigidity lower limb exoskeleton robot
CN112318490B (en) Light and flexible knee joint power assisting exoskeleton robot
CN109044742B (en) Rehabilitation type lower limb exoskeleton
RU156507U1 (en) EXCOSCELETON OF THE LOWER EXTREMITIES
CN112008701A (en) Hip joint assistance exoskeleton system capable of assisting in supporting load
CN111281744A (en) Modular joint and wearable modular joint exoskeleton
CN108969310A (en) A kind of lower limb booster type exoskeleton robot
CN112022618B (en) Rigid-flexible coupling wearable walking assisting exoskeleton system
CN110897834A (en) Adjustable lower limb exoskeleton device suitable for gait training of cerebral palsy children
CN207341906U (en) A kind of wearable bionical hydraulic pressure lower limb rehabilitation walk help mechanical device
CN108214457B (en) Passive trunk labor-saving device for lower limb exoskeleton
CN112168442A (en) Variable-rigidity ankle joint
CN209734461U (en) Exoskeleton robot for leg rehabilitation training and body building
CN117064702A (en) Wearable flexible lower limb gravity balance exoskeleton
WO2023070466A1 (en) Walking assistance exoskeleton apparatus
CN110623817A (en) Unpowered hip joint energy storage walking aid exoskeleton
CN213218751U (en) Recovered ectoskeleton robot
CN211272090U (en) Lower limb exoskeleton rehabilitation robot
Zhou et al. Analysis, design and preliminary evaluation of an anthropometric self-stabilization passive exoskeleton for enhancing the ability of walking with loads

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination