WO2022222503A1

WO2022222503A1 - Motion decoupling parallel-driven exoskeleton robot ankle joint

Info

Publication number: WO2022222503A1
Application number: PCT/CN2021/138023
Authority: WO
Inventors: 刘静帅; 吴新宇; 何勇; 李金科; 李锋; 马跃; 曹武警; 王大帅; 孙健铨; 连鹏晨
Original assignee: 中国科学院深圳先进技术研究院
Priority date: 2021-04-23
Filing date: 2021-12-14
Publication date: 2022-10-27
Also published as: CN113183176B; CN113183176A

Abstract

A motion decoupling parallel-driven exoskeleton robot ankle joint, comprising an ankle joint driving assembly (1) and a foot support assembly (2). The ankle joint driving assembly (1) comprises a shank rod (11), a flexion driving assembly, and an inversion/eversion motion assembly. The shank rod (11) is hingedly connected to the foot support assembly (2). The flexion driving assembly and the inversion/eversion motion assembly are disposed on the shank rod (11), and respectively drive the foot support assembly (2) to perform a flexion motion and an inversion/eversion motion. With such configuration, the motion decoupling parallel-driven structure has characteristics of two degrees of freedom of rotation, good structural rigidity, high overall center of gravity, and low inertia of the foot, active motion assistance of the ankle joint in two degrees-of-freedom of dorsiflexion/plantar flexion and inversion/eversion is achieved, and the wearing comfort, motion flexibility and stability of the human body are improved.

Description

A motion decoupling parallel drive exoskeleton robot ankle joint

technical field

The invention belongs to the technical field of robots, and relates to a motion decoupling parallel driving type exoskeleton robot ankle joint.

Background technique

The lower extremity exoskeleton is a wearable bionic robot similar in structure to the lower extremities of the human body. It can assist the wearer to achieve lower extremity rehabilitation, assist walking, and enhance weight-bearing functions. It has broad application prospects in the fields of rehabilitation, civil and military. According to the research on the motion mechanism of human joints, the ankle joint is composed of the fork-shaped joint socket formed by the lower articular surface of the tibia, the medial ankle joint surface and the lateral ankle joint surface, and the ankle joint head of the talus. It can do dorsiflexion/plantar flexion around three rotation axes. Flexion, varus/valgus, and minor internal/external rotation movements, with good flexibility and strong support.

Existing lower limb exoskeleton robots have a single degree of freedom of the ankle joint, usually only including a single degree of freedom of dorsiflexion/plantar flexion, and even use an integrated rigid structure with the calf, and most of them do not have active driving, which greatly affects the exoskeleton. flexibility, wearing comfort, and ankle movement assisting ability. Therefore, how to design a wearable exoskeleton robot ankle joint with high overall structural rigidity to realize active motion assistance with two degrees of freedom of dorsiflexion/plantar flexion and varus/valgus is a key in the development process of lower limb exoskeleton robots problem.

technical problem

In order to overcome the deficiencies of the prior art, the present invention proposes a motion decoupling parallel drive exoskeleton robot ankle joint. The small end inertia feature realizes active ankle motion assistance with two degrees of freedom of dorsiflexion/plantar flexion and varus/valgus, improving the comfort, flexibility and stability of human wearing.

The technical solution of the present invention to solve the above problems is: a motion decoupling parallel drive exoskeleton robot ankle joint, the special feature of which is:

Including ankle joint drive components, foot support components;

The ankle joint drive assembly includes: a calf rod, a flexion and extension drive assembly, and a varus motion assembly;

The calf rod is hinged with the foot rest assembly, the flexion-extension drive assembly and the inversion motion assembly are arranged on the calf rod, and the flexion and extension drive assembly and the inversion motion assembly respectively drive the foot rest assembly to perform flexion-extension motion and inversion motion.

Further, the above-mentioned flexion and extension drive assembly includes a flexion and extension drive fixing seat, a flexion and extension drive unit, a flexion and extension motion output end cover, a flexion and extension motion transmission rod, and an ankle joint fixed support;

The flexion and extension drive unit is fixed on the upper end of the calf rod through the flexion and extension drive fixing seat. One end is hinged with the ankle joint fixed support; the ankle joint fixed support is fixedly connected with the foot support component.

Further, the other end of the above-mentioned flexion and extension motion transmission rod is connected with the ankle joint fixed support through a flexion and extension motion Hook hinge.

Further, the power output end of the flexion and extension drive unit is hinged with one end of the flexion and extension motion transmission rod through a flexion and extension motion uniaxial hinge.

Further, the calf rod and the ankle joint fixing support are connected by the calf rod supporting Hook hinge.

Further, the above-mentioned inversion motion assembly includes an inversion drive unit, the inversion drive unit is fixed on the upper part of the calf rod and is located below the flexion and extension drive unit, and the power output end of the inversion drive unit is connected with the inversion movement output end cover, and the inversion and outversion are connected. The movement output end cover is connected with one end of the inversion movement transmission rod through the inversion movement radial hinge, the inversion movement horizontal hinge, and the inversion movement vertical hinge, and the other end of the inversion movement transmission rod is hinged with the ankle joint fixed support.

Further, the other end of the above-mentioned inversion movement transmission rod is connected with the ankle joint fixed support through the inversion movement Hook hinge.

Further, the above-mentioned foot support assembly includes a strap ring buckle, an L-shaped ring buckle fixing seat, and a foot support bottom plate; the L-shaped ring buckle fixing seat is fixed on the foot support bottom plate, and the strap ring buckle is fixed on the L-shaped ring buckle fixing seat. .

Further, it also includes calf binding and foot binding; the calf binding and foot binding are respectively arranged on the calf rod and the strap ring buckle.

beneficial effect

Advantages of the present invention:

1) Compared with the prior art, the exoskeleton robot ankle joint proposed by the present invention adopts a novel two-degree-of-freedom parallel mechanism configuration to provide ankle joint dorsiflexion/plantar flexion and ankle joint varus/valgus active motion assistance, And the motion decoupling between the two simplifies motion control;

2) Hook hinge is used to connect the calf rod and the fixed seat, with two mutually perpendicular rotation axes, providing two degrees of freedom of movement of ankle joint dorsiflexion/plantar flexion and varus/valgus;

3) The calf rod, the flexion and extension drive output motion end cover, the flexion and extension transmission rod and the ankle joint fixed seat form a parallelogram mechanism, which serves as the ankle joint dorsiflexion/plantar flexion movement branch chain, and the flexion and extension drive unit is installed at the knee joint position to improve the center of gravity position and reduce the inertia of the foot end; the calf rod, the inversion drive output movement end cover, the inversion transmission rod and the ankle joint fixation form a parallelogram mechanism, which is used as the ankle joint inversion/valgus movement branch chain, and the inversion drive unit is installed in the The lower part of the flexion and extension drive unit can improve the position of the center of gravity and reduce the inertia of the foot; the physical position of the two drives is higher, which improves the overall center of gravity and reduces the additional inertia of the foot, thereby improving the flexibility of dynamic movement;

4) The flexion-extension movement branch A ₀ ABB ₀ and the varus movement branch B ₀ C ₀ CD are perpendicular to each other, the former has two uniaxial rotation hinges and a Hooke hinge, and the latter has a uniaxial rotation hinge , 1 Hooker hinge and 1 equivalent spherical hinge, and the Hooker hinge and the axis of the Hooker hinge supported by the calf rod are collinear or parallel; compared with the distributed multi-branch parallel structure, the vertically arranged two The chain parallel structure is more compact, and there is no movement interference between the branches.

Description of drawings

Figure 1 is a schematic diagram of the ankle joint mechanism of the exoskeleton robot;

Fig. 2 is the schematic diagram of exoskeleton robot ankle joint human body wearing;

Fig. 3 is a schematic diagram of the structure of the ankle joint of the exoskeleton robot;

Figure 4 is a cross-sectional view of the branched structure of the exoskeleton robot ankle joint flexion and extension movement;

Figure 5 is a cross-sectional view of a branched chain structure of an exoskeleton robot ankle joint varus motion;

Fig. 6 is a schematic diagram of the exoskeleton robot ankle joint in dorsiflexion motion state;

Figure 7 is a schematic diagram of the exoskeleton robot ankle joint in plantar flexion;

Figure 8 is a schematic diagram of an exoskeleton robot ankle joint in varus motion;

Figure 9 is a schematic diagram of the exoskeleton robot ankle joint in the eversion motion state;

Fig. 10 is a schematic diagram of an exoskeleton robot ankle joint in a compound motion state.

Among them: 1. Ankle joint drive assembly;

11. Calf rod; 12. Output end cover for flexion and extension; 13. Uniaxial hinge for flexion and extension; 14. Transmission rod for flexion and extension; 15. Hook hinge for flexion and extension; ; 18, flexion and extension drive unit; 19, inversion drive unit; 110, inversion movement output end cover; 111, inversion movement radial hinge; 112, inversion movement horizontal hinge; 113, inversion movement vertical hinge; 114, Inversion movement transmission rod; 115. Inversion movement Hook hinge; 116. Calf rod support Hook hinge;

2. Foot rest components;

21. Strap ring buckle; 22. L-shaped ring buckle fixing seat; 23. Foot support bottom plate;

3. Calf binding; 4. Foot binding.

Embodiments of the present invention

In order to make the purposes, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments These are some embodiments of the present invention, but not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention. Accordingly, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but is merely representative of selected embodiments of the invention.

In order to provide dorsiflexion/plantar flexion and varus/valgus active motion assistance for the human ankle joint, the present invention proposes a parallel-driven exoskeleton robot ankle joint with two rotational degrees of freedom completely decoupled. First, in order to improve the bearing capacity and structural rigidity of the ankle joint, a two-branch parallel mechanism configuration based on the Hooke hinge is adopted, and the schematic diagram of the mechanism is shown in Figure 1. The mechanism consists of two mutually perpendicular motion branches A ₀ ABB ₀ and B ₀ C ₀ CD , among which, A ₀ , A , D are uniaxial rotation hinges, C is spherical hinges, and B ₀ , B , C ₀ are tigers The gram hinge corresponds to the ankle joint flexion and extension branch and the ankle joint inversion branch; secondly, in order to realize the decoupling of the two-degree-of-freedom rotational motion of the ankle joint and facilitate the motion control, the size parameters of the two motion branches are designed as The opposite sides are equal to form a parallelogram-like mechanism; finally, in order to improve the center of gravity of the exoskeleton ankle joint and reduce the additional motion inertia of the foot end, the drive unit A ₀ for flexion and extension motion is installed at the axis of the knee joint, while the inversion motion The drive unit ( D ) is mounted vertically adjacent to the drive unit ( A ₀ ), both of which transmit motion remotely to the ankle joint via a link. Compared with the existing exoskeleton robot ankle joint, the mechanism has more degrees of freedom, more flexible movement, large load capacity and high rigidity in parallel configuration, and the size of the mechanism meets the condition of equal opposite sides. It is driven by dual motors and has a range of motion. It has the characteristics of large size, motion decoupling, and easy operation and control. It can not only be used for the motion assistance of the ankle joint alone, but also can be combined with the knee joint exoskeleton and the hip joint exoskeleton to form a fully articulated lower limb exoskeleton robot.

The exoskeleton robot ankle joint provided by the present invention mainly includes an ankle joint driving component 1, a foot support component 2, a calf binding 3, and a foot binding 4, and the human body wearing effect is shown in FIG. 2 . Since the structures on both sides of the left and right legs are symmetrical, the left side is taken as an example for detailed description. The overall structure is shown in Figure 3, which includes an ankle joint drive assembly 1 and a foot support assembly 2; the ankle joint drive assembly 1 includes: a calf Rod 11, flexion and extension drive assembly and inversion motion assembly; calf rod 11 is hinged with foot rest assembly 2, flexion and extension drive assembly and inversion motion assembly are arranged on calf rod 11, flexion extension drive assembly and inversion motion assembly respectively drive the foot rest assembly 2. Perform flexion-extension movement and inversion movement. The calf binding 3 and the foot binding 4 are respectively located on the calf rod 11 and the foot support assembly 2.

As a preferred embodiment of the present invention, the above-mentioned flexion and extension drive assembly includes a flexion and extension drive fixed seat 17 , a flexion and extension drive unit 18 , a flexion and extension motion output end cover 12 , a flexion and extension motion transmission rod 14 , and an ankle joint fixed support 16 . The flexion and extension drive unit 18 is fixed on the upper end of the calf rod 11 through the flexion and extension drive fixing seat 17 . , the other end of the flexion and extension motion transmission rod 14 is hinged with the ankle joint fixed support 16 ; the ankle joint fixed support 16 is fixedly connected with the foot support assembly 2 .

As a preferred embodiment of the present invention, the other end of the flexion and extension motion transmission rod 14 is connected with the ankle joint fixing support 16 through the flexion and extension motion Hook hinge 15 .

As a preferred embodiment of the present invention, the power output end of the flexion and extension drive unit 18 is hinged with one end of the flexion and extension motion transmission rod 14 through the flexion and extension motion uniaxial hinge 13 .

As a preferred embodiment of the present invention, the calf rod 11 and the ankle joint fixing support 16 are connected through the calf rod supporting Hook hinge 116 .

As a preferred embodiment of the present invention, the above-mentioned inversion movement assembly includes an inversion drive unit 19 . The inversion drive unit 19 is fixed on the upper part of the calf bar 11 and located below the flexion and extension drive unit 18 . The power output end of the inversion drive unit 19 It is connected with the output end cap 110 of the inversion movement. Since the existing spherical hinge cannot meet the requirements of the ankle joint varus/valgus motion angle, the spherical hinge C shown in Figure 1 is decomposed into three mutually perpendicular single-degree-of-freedom rotary hinges (radial hinge 111, horizontal hinge 112 and hinge 113). The output end cover 110 of the inversion movement is connected to one end of the inversion movement transmission rod 114 through the inversion movement radial hinge 111, the inversion movement horizontal hinge 112, and the inversion movement vertical hinge 113, and the other end of the inversion movement transmission rod 114 is connected with the inversion movement transmission rod 114. The ankle joint fixation support 16 is hinged.

As a preferred embodiment of the present invention, the other end of the above-mentioned varus motion transmission rod 114 is connected to the ankle joint fixing support 16 through the varus motion Hook hinge 115 .

As a preferred embodiment of the present invention, the above-mentioned foot rest assembly 2 includes a strap ring buckle 21, an L-shaped ring buckle fixing seat 22, and a foot support bottom plate 23; the number of the L-shaped ring buckle fixing seat 22 is four, and the L-shaped ring The buckle fixing base 22 is fixed on the foot support bottom plate 23 , the strap loop buckle 21 is fixed on the L-shaped loop buckle fixing base 22 , and the foot binding 4 is arranged on the strap loop buckle 21 .

The working principle of the exoskeleton robot ankle joint of the present invention:

When determining the configuration of the exoskeleton robot ankle joint mechanism, as shown in Figure 1. First of all, in order to realize the dorsiflexion/plantar flexion of the ankle joint of the exoskeleton robot, that is, the flexion and extension movement, and at the same time, in order to improve the overall center of gravity position and reduce the inertia of the foot end, the active part ( A ₀ ) of the flexion and extension movement is set at the axis of the knee joint , a single-degree-of-freedom planar four-bar mechanism ( A ₀ ABB ₀ ) is used for motion transmission to form a branch chain of flexion and extension; secondly, in order to achieve ankle varus/valgus motion, that is, the inside-outside and inside-outside perpendicular to the axis of dorsiflexion/plantar flexion motion Inverting motion, the two uniaxial rotating hinges B ₀ and B of the flexing and stretching motion branch A ₀ ABB ₀ are evolved into Hooke hinges, so as to obtain the in-and-out rotation axis perpendicular to the flexing and stretching motion axis, and B ₀ and B form a motion plane π ; Again, in order to drive the varus/valgus motion of the ankle joint, a six-degree-of-freedom spatial motion branch (Hooker hinge C ₀ spherical hinge C rotational hinge D ) is added, and C ₀ is located on the motion plane π, and D is located on A ₀ B ₀ , so as to form a branch chain B ₀ C ₀ CD of varus and varus motion, and at the same time, the active part ( D ) of varus and varus movement is arranged below the active part ( A ₀ ) of flexion and extension movement, so as to improve the overall center of gravity and reduce the foot end Inertia; finally, in order to achieve motion decoupling, the planes where the two motion branches are located are perpendicular to each other, and the three Hooke hinges B , B ₀ and C ₀ are located in the same motion plane π. At the same time, in order to facilitate motion control, the size of the mechanism satisfies The requirements for equal sides ( A ₀ B ₀ = AB , A ₀ A = BB ₀ , C ₀ C = B ₀ D , B ₀ C ₀ = CD ), form two parallelogram-like mechanisms with a transmission ratio equal to 1 , so that both kinematic chains are equivalent to direct drives.

Figure 4 is a cross-sectional view of the structure of the ankle joint flexion and extension chain structure of the exoskeleton robot, which is mainly composed of four components: a calf rod 11, a flexion and extension output end cover 12, a flexion and extension transmission rod 14, and an ankle joint fixed support 16. The drive unit 18 ( A ₀ ), the flexion-extension movement uniaxial hinge 13 ( A ), the flexion-extension movement Hooker hinge 15 ( B ) and the calf rod support Hooker hinge 116 ( B ₀ ) are connected, and the flexion-extension movement coincides with the axis of the knee joint of the human body. The drive unit 18 is installed on the flexion and extension drive fixing seat 17, when the flexion and extension motion output end cap 12 rotates clockwise under the action of the flexion and extension drive unit 18, the flexion and extension motion transmission rod 14 transmits the flexion and extension motion to the ankle joint fixing seat 16, resulting in an ankle The joint dorsiflexion motion is shown in FIG. 6 ; on the contrary, when the flexion and extension motion output end cap 12 rotates counterclockwise, the ankle joint plantar flexion motion is generated, as shown in FIG. 7 .

Figure 5 is a cross-sectional view of the structure of the exoskeleton robot ankle joint varus motion branch chain, which is mainly composed of four components: the calf rod 11, the varus motion output end cover 110, the varus motion transmission rod 114, and the ankle joint fixed support 16. Through the inversion drive unit 19 ( D ), the inversion movement radial hinge 111, the inversion movement horizontal hinge 112, the inversion movement vertical hinge 113 (inversion movement radial hinge 111, inversion movement horizontal hinge 112, inversion movement The motion vertical hinge 113 is combined into a ball hinge C ), a varus motion Hooke hinge 115 ( C ₀ ) and a calf rod support Hooke hinge 116 ( B ₀ ) to connect, and the flexion and extension drive unit 18 is perpendicular to the varus drive unit 19 is installed on the calf rod 11, when the output end cap 110 of the inversion movement is rotated clockwise under the action of the inversion drive unit 19, the inversion movement is transmitted to the ankle joint fixing seat 16 through the inversion movement transmission rod 114, resulting in an ankle joint. The varus motion of the joint is shown in FIG. 8 ; on the contrary, when the output end cap 110 of the varus motion is rotated counterclockwise, the valgus motion of the ankle joint is generated, as shown in FIG. 9 .

If the flexion-extension movement branch and the varus movement branch of the ankle joint of the exoskeleton robot move at the same time, the compound motion of ankle joint dorsiflexion/plantar flexion and varus/valgus can be generated, as shown in Figure 10.

The above descriptions are only the embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the description and drawings of the present invention, or directly or indirectly applied to other related The system field is similarly included in the protection scope of the present invention.

Claims

A motion decoupling parallel-driven exoskeleton robot ankle joint, characterized in that:

Including an ankle joint drive assembly (1) and a foot support assembly (2);

The ankle joint drive assembly (1) includes: a calf rod (11), a flexion and extension drive assembly, and a varus motion assembly;

The calf rod (11) is hinged with the foot rest assembly (2), the flexion-extension drive assembly and the inversion motion assembly are arranged on the calf rod (11), and the flexion and extension drive assembly and the inversion motion assembly respectively drive the foot rest assembly (2) to carry out the movement. Flexion and inversion exercises.
A motion decoupling parallel-driven exoskeleton robot ankle joint according to claim 1, characterized in that:

The flexion and extension drive assembly comprises a flexion and extension drive fixing seat (17), a flexion and extension drive unit (18), a flexion and extension motion output end cover (12), a flexion and extension motion transmission rod (14), and an ankle joint fixing support (16);

The flexion and extension drive unit (18) is fixed on the upper end of the calf rod (11) through the flexion and extension drive fixing seat (17). (12) is hinged with one end of the flexion and extension motion transmission rod (14), and the other end of the flexion and extension motion transmission rod (14) is hinged with the ankle joint fixed support (16); the ankle joint fixed support (16) is connected with the foot support assembly (2) ) is fixed.
A motion decoupling parallel-driven exoskeleton robot ankle joint according to claim 2, characterized in that:

The other end of the flexion and extension motion transmission rod (14) is connected with the ankle joint fixing support (16) through the flexion and extension motion Hook hinge (15).
A motion decoupling parallel-driven exoskeleton robot ankle joint according to claim 3, characterized in that:

The power output end of the flexion and extension drive unit (18) is hinged with one end of the flexion and extension motion transmission rod (14) through a flexion and extension motion uniaxial hinge (13).
A motion decoupling parallel-driven exoskeleton robot ankle joint according to claim 4, characterized in that:

The calf rod (11) is connected with the ankle joint fixing support (16) through the calf rod supporting Hook hinge (116).
A motion decoupling parallel-driven exoskeleton robot ankle joint according to claim 5, characterized in that:

The inversion movement assembly includes an inversion drive unit (19), the inversion drive unit (19) is fixed on the upper part of the calf bar (11) and is located below the flexion and extension drive unit (18), and the power of the inversion drive unit (19) The output end is connected with the output end cover (110) of the inversion movement, and the output end cover (110) of the inversion movement is connected by the inversion movement radial hinge (111), the inversion movement horizontal hinge (112), the inversion movement vertical hinge (113) ) is connected with one end of the inversion movement transmission rod (114), and the other end of the inversion movement transmission rod (114) is hinged with the ankle joint fixing support (16).
A motion decoupling parallel-driven exoskeleton robot ankle joint according to claim 6, characterized in that:

The other end of the inversion movement transmission rod (114) is connected with the ankle joint fixing support (16) through the inversion movement Hook hinge (115).
A motion decoupling parallel-driven exoskeleton robot ankle joint according to claim 7, characterized in that:

The foot support assembly (2) includes a strap ring buckle (21), an L-shaped ring buckle fixing seat (22), and a foot support bottom plate (23); the L-shaped ring buckle fixing seat (22) is fixed on the foot support bottom plate (23) ), the strap loop buckle (21) is fixed on the L-shaped loop buckle fixing seat (22).
A motion decoupling parallel-driven exoskeleton robot ankle joint according to claim 8, characterized in that:

It also includes a calf binding (3) and a foot binding (4); the calf binding (3) and the foot binding (4) are respectively arranged on the calf rod (11) and the strap ring buckle (21).