Shank structure of lower limb exoskeleton and exoskeleton robot

Abstract

The invention belongs to the technical field of exoskeleton robots, and relates to a shank structure of a lower limb exoskeleton and an exoskeleton robot. A shank structure of the lower limb exoskeleton comprises a flexion / extension joint motor which is installed on the upper portion of a shank structural part, the lower portion of the shank structural part is rotationally connected with an ankle connecting part, the output end of the flexion / extension joint motor is connected with a motor output part, the motor output part is hinged to the upper end of a connecting rod, and the lower end of the connecting rod is hinged to the front end of the ankle connecting part. An adduction / extroversion joint motor is mounted at the rear end of the ankle connecting piece; the flexion / extension joint motor transmits power to the ankle connecting piece through the output piece and the connecting rod, and foot flexion / extension movement is achieved. The shank structure of the lower limb exoskeleton, provided by the invention, can realize ankle flexion / extension and adduction / extroversion movement under the driving of the motor, so that natural movement of a human shank is fitted to the greatest extent, and the flexibility and adaptability of the exoskeleton shank are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of exoskeleton robots and relates to a calf structure of a lower limb exoskeleton and an exoskeleton robot. Background Art

[0002] Lower limb exoskeleton robots are widely used in the fields of rehabilitation medicine, walking assistance, and military. Their core function is to provide power support for the lower limb movement of users. The traditional exoskeleton calf structures generally have problems such as insufficient decoupling of ankle joint degrees of freedom, poor support rigidity, and low movement smoothness. For example, in the prior art, the mechanical adjustment scheme relies on hinges and locking devices, which is laborious to adjust and lacks flexibility; although the electric drive scheme has high precision, it has a complex structure, a bulky volume, and multi-degree-of-freedom control is easily affected by motion interference. In addition, the traditional design arranges the motor near the ankle joint, resulting in a lower center of gravity and affecting the movement smoothness.

[0003] In the existing patents, some technologies improve the adaptability of the ankle joint through spring energy storage or spherical joints, but have defects such as low assistance efficiency and poor load-bearing capacity (such as the patent with the publication number CN118453355A, titled "An Ankle Joint Variable Stiffness Torque Simulation Device and Its Ankle Joint Assistance Exoskeleton"); some other technologies adopt single-degree-of-freedom designs and cannot meet the multi-directional movement requirements of the foot (such as the patent with the publication number CN221331813U, titled "A Lower Limb Exoskeleton Ankle Joint Booster"). Therefore, there is an urgent need for an exoskeleton calf structure that can achieve two-degree-of-freedom decoupling control of the ankle joint and has high impact resistance and movement smoothness. Summary of the Invention

[0004] To solve the above technical problems, the present invention proposes a calf structure of a lower limb exoskeleton, which can achieve ankle flexion / extension and adduction / abduction movements under the drive of a motor, and can fit the natural movement of the human calf to the greatest extent, improving the flexibility and adaptability of the exoskeleton calf.

[0005] The technical solution of the present invention to solve the above problems is: A calf structure of a lower limb exoskeleton, which is characterized in that:

[0006] It includes a flexion / extension joint motor, which is installed on the upper part of the calf structure member, and the lower part of the calf structure member is rotatably connected to the ankle connecting member.

[0007] The output end of the flexion / extension joint motor is connected to the motor output member, the motor output member is hinged to the upper end of the connecting rod, the lower end of the connecting rod is hinged to the front end of the ankle connecting member, and an adduction / abduction joint motor is installed at the rear end of the ankle connecting member.

[0008] The flexion / extension joint motor transmits power to the ankle connecting member through the output member and the connecting rod to achieve foot flexion / extension movement.

[0009] Further, the above-mentioned ankle connecting member is installed between the calf structural member and the calf auxiliary connecting member through the crossed roller bearing I and the crossed roller bearing II, forming a frame structure, which improves the impact resistance of the calf.

[0010] Further, the calf structure of the above-mentioned lower limb exoskeleton further includes a sole component and an ankle auxiliary connecting member. The sole component is installed on the ankle connecting member through the crossed roller bearing III. The adduction / abduction joint motor directly drives the sole component to rotate to realize the adduction / abduction movement of the foot; one end of the ankle auxiliary connecting member is installed on the crossed roller bearing III, and the other end is installed on the ankle connecting member, forming a frame structure, which improves the impact resistance of the ankle.

[0011] Further, the above-mentioned sole component includes an upper foot board, a lower foot board and a force sensor. The force sensor is installed between the upper foot board and the lower foot board for real-time monitoring of the sole pressure.

[0012] Further, the above-mentioned ankle connecting member is of an L-shaped structure. The connecting rod and the calf structural member are located on one side of the L-shaped structure, and the sole component is located on the other side of the L-shaped structure.

[0013] Further, the rear end of the above-mentioned upper foot board is provided with a connecting end. The upper foot board is installed on the ankle connecting member through the hole positions on the connecting end in cooperation with the crossed roller bearing III.

[0014] Further, the above-mentioned lower foot board and the force sensor are installed at the bottom of the upper foot board by screws.

[0015] Further, the above-mentioned calf structural member and the calf auxiliary connecting member adopt a hollow design to reduce the weight.

[0016] Further, the upper and lower ends of the above-mentioned connecting rod are respectively connected to the motor output member and the ankle connecting member through the pin shaft assembly I and the pin shaft assembly II to form a rotating pair.

[0017] Further, the above-mentioned calf auxiliary connecting member and the ankle auxiliary connecting member are respectively fixed to the calf structural member and the ankle connecting member by screws.

[0018] In addition, the present invention also proposes an exoskeleton robot, which is characterized in that it includes the calf structure of the above-mentioned lower limb exoskeleton.

[0019] Advantages of the present invention:

[0020] 1) By driving the two degrees of freedom of the ankle joint through the flexion / extension joint motor and the adduction / abduction joint motor respectively, the two-degree-of-freedom decoupled movement is realized, and the movement of the human ankle joint is fitted to the greatest extent;

[0021] 2) Adopting a frame structure improves the overall structural stiffness;

[0022] 3) The use of crossed roller bearings enhances the ankle joint's ability to resist external impacts and extends its service life.

[0023] 4) The adoption of a series - parallel hybrid structure for the joint enables both degrees of freedom of the ankle joint to have a sufficiently large range of motion without generating motion interference.

[0024] 5) The use of a motor - driven form provides a better assisting effect for the calf of the user. The abduction / adduction joint motor directly drives the upper foot plate, simplifying the transmission chain and improving the response speed.

[0025] 6) The use of an upper - mounted motor with remote transmission moves the overall center of mass of the calf upward, improving the smoothness of calf movement.

[0026] 7) A space is reserved at the ankle joint to avoid interference with the human foot. Description of the Drawings

[0027] Figure 1 is a schematic diagram of the exoskeleton calf worn by a human body;

[0028] Figure 2 is a schematic diagram of the overall structure of the right - hand exoskeleton calf;

[0029] Figure 3 is a schematic diagram of the disassembled structure of the right - hand exoskeleton calf;

[0030] Figure 4 is a schematic diagram of the exoskeleton calf ankle joint in the flexion state;

[0031] Figure 5 is a schematic diagram of the exoskeleton calf ankle joint in the adduction state.

[0032] Among them: flexion / extension joint motor - 1, calf structural member - 2, abduction / adduction joint motor - 3, motor output member - 4, pin shaft combination I - 5, connecting rod - 6, pin shaft combination II - 7, ankle connecting member - 8, crossed roller bearing I - 9, crossed roller bearing II - 10, calf auxiliary connecting member - 11, crossed roller bearing III - 12, ankle auxiliary connecting member - 13, upper foot plate - 14, force sensor - 15, lower foot plate - 16. Detailed Implementation Manner

[0033] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the protection scope of the present invention. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed present invention, but merely represents selected embodiments of the present invention.

[0034] The present invention proposes a calf structure of a lower limb exoskeleton, applying motor drive to the design of the lower limb exoskeleton calf structure, simulating the two-degree-of-freedom movement of the human ankle joint, and helping lower limb paralyzed patients achieve flexible calf movement when wearing the lower limb exoskeleton, such as Figure 1 As shown, the exoskeleton calf is arranged on the outside of the human calf and interacts by binding to the human body. The adduction / abduction and flexion / extension degrees of freedom of the exoskeleton calf correspond to the degrees of freedom of the human calf ankle joint to achieve anthropomorphic movement of the exoskeleton calf.

[0035] A schematic diagram of the overall structure of the right exoskeleton calf is as shown in Figure 2 As shown. Since the calf structure is designed to be symmetric on the left and right sides, only the right calf structure will be described here.

[0036] Refer to the attached Figure 2 and Figure 3 The calf structure of the lower limb exoskeleton proposed by the present invention includes a flexion / extension joint motor 1, which is installed on the upper part of the calf structure member 2 by bolts, and the lower part of the calf structure member 2 is rotatably connected to the ankle connecting member 8. The output end of the flexion / extension joint motor 1 is connected to the motor output member 4. The motor output member 4 is hinged to the upper end of the connecting rod 6, and the lower end of the connecting rod 6 is hinged to the front end of the ankle connecting member 8. An adduction / abduction joint motor 3 is installed at the rear end of the ankle connecting member 8. The flexion / extension joint motor 1 transmits power to the ankle connecting member 8 through the output member 4 and the connecting rod 6 to achieve foot flexion / extension movement. The calf structure member 2, the motor output member 4, the connecting rod 6, and the ankle connecting member 8 are connected in sequence to form a four-bar linkage structure. At the same time, placing the joint motor above the calf raises the overall center of mass of the calf and improves the smoothness of calf movement.

[0037] The power output end of the flexion / extension joint motor 1 transmits power to the foot through a series of transmission linkages to achieve the flexion / extension movement of the foot. It concentrates the center of mass of the calf on the upper part of the calf, making the calf movement smoother. The adduction / abduction joint motor -3 is installed at the rear end of the calf ankle joint, and its power output end is directly connected to the foot to directly drive the adduction / abduction movement of the foot. The two motors are connected by a series of rods, preventing the interference problem between two different directions of movement and increasing the flexibility of the foot movement. The motor can be a servo motor or a stepper motor.

[0038] Specifically, refer to Figure 3 , the ankle connecting piece 8 is installed between the calf structural member -2 and the calf auxiliary connecting piece 11 through the crossed roller bearing I9 and the crossed roller bearing II10, forming a frame structure, which improves the impact resistance of the calf.

[0039] Specifically, refer to Figure 3 , the calf structure of the lower limb exoskeleton further includes a sole component and an ankle auxiliary connecting piece 13. The sole component is installed on the ankle connecting piece 8 through the crossed roller bearing III12. The adduction / abduction joint motor 3 directly drives the sole component to rotate to achieve the adduction / abduction movement of the foot; one end of the ankle auxiliary connecting piece 13 is installed on the crossed roller bearing III12, and the other end is installed on the ankle connecting piece 8, forming a frame structure, which improves the impact resistance of the ankle.

[0040] An auxiliary support structure is adopted at the ankle joint of the exoskeleton calf, forming a double support frame structure, which improves the anti-external impact ability of the calf root and the ankle joint and improves the movement safety.

[0041] Specifically, refer to Figure 3 , the above-mentioned sole component includes an upper foot board 14, a lower foot board 16 and a force sensor 15. The force sensor 15 is installed between the upper foot board 14 and the lower foot board 16 to monitor the sole pressure in real time.

[0042] Through the above connection method, the power output by the flexion / extension joint motor -1 is transmitted to the connecting rod -6, and then transmitted to the front end of the ankle connecting piece -8 through the rotating pair. Since the middle part of the ankle connecting piece -8 is connected to the calf structural member -2 through the crossed roller bearing, the connecting rod -6 will drive the connecting piece -8 to make an arc movement around the rotating pair in the middle, so as to achieve the flexion / extension movement of the ankle joint. The adduction / abduction joint motor -3 directly drives the upper foot board -14 to rotate to achieve the adduction / abduction movement of the ankle joint.

[0043] Specifically, refer to Figure 3 and Figure 4, the above-mentioned ankle connecting member 8 is of an L-shaped structure. The connecting rod 6 and the calf structural member -2 are located on one side of the L-shaped structure, and the sole assembly is located on the other side of the L-shaped structure. The L-shaped structure leaves enough space at the ankle joint of the exoskeleton calf, improving the wearing comfort of the user and also enhancing the flexibility of the ankle joint movement.

[0044] Specifically, referring to Figure 4 , a connection end is provided at the rear end of the above-mentioned upper foot plate 14. The upper foot plate 14 is cooperatively installed on the ankle connecting member 8 through the holes at the connection end and the crossed roller bearing III12. The above-mentioned lower foot plate 16 and the force sensor 15 are installed at the bottom of the upper foot plate 14 by screws.

[0045] Specifically, referring to Figure 4 , the above-mentioned calf structural member 2 and the calf auxiliary connecting member 11 adopt a hollow design to reduce weight. The upper and lower ends of the above-mentioned connecting rod 6 are respectively connected to the motor output member 4 and the ankle connecting member 8 through the pin assembly I5 and the pin assembly II7 to form a rotating pair. The above-mentioned calf auxiliary connecting member 11 and the ankle auxiliary connecting member 13 are respectively fixed to the calf structural member 2 and the ankle connecting member 8 by screws.

[0046] The schematic diagram of the exoskeleton calf ankle joint in the flexion state is as shown in Figure 4 . Driven by the flexion / extension joint motor 1, the exoskeleton calf drives the human calf to achieve the foot flexion movement. The schematic diagram of the exoskeleton calf ankle joint in the adduction state is as shown in Figure 5 . Driven by the adduction / abduction joint motor 3, the exoskeleton calf drives the human calf to achieve the foot adduction movement.

[0047] The present invention also proposes an exoskeleton robot, which includes the calf structure of the above-mentioned lower limb exoskeleton. Thus, this exoskeleton robot also has all the functions and effects of the calf structure of the above-mentioned lower limb exoskeleton, which will not be elaborated here.

[0048] In summary, the present invention arranges two motors on the calf of the exoskeleton. Driven by the motors, the exoskeleton ankle joint realizes the adduction / abduction and flexion / extension movements of the foot, maximizing the simulation of the movement of the human ankle joint. The flexion / extension joint motor is installed on the upper part of the calf structural member. The power is transmitted from the output end of the motor to the calf ankle joint through a connecting member and a connecting rod to realize the flexion / extension movement of the sole of the foot. Through this long-distance transmission method with the motor placed above, the overall center of mass of the calf can be made higher, enabling more effective stable control of the calf during movement. The adduction / abduction joint motor is arranged at the rear end of the ankle joint, and the adduction / abduction movement of the sole of the foot is realized through direct drive. The adduction / abduction joint motor and the flexion / extension joint motor are connected in series through a series of transmission rods, decoupling the adduction / abduction movement and the flexion / extension movement of the ankle joint from each other and not affecting each other, allowing both degrees of freedom of the ankle joint to have a large range of motion and making the foot movement more flexible. The connection of the calf ankle joint is designed as a frame structure. Specifically, crossed roller bearings are installed at the power output of the ankle joint, and then each auxiliary support is installed on the bearings, enabling the auxiliary support to move together with the output end of the motor, thus forming a frame structure. Since the crossed roller bearings have the ability to withstand large axial impact loads, the anti-external impact ability of this ankle joint structure is significantly improved.

[0049] The above are only the embodiments of the present invention, and do not limit the protection scope of the present invention accordingly. Any equivalent structural or equivalent process transformation made by using the content of the specification and drawings of the present invention, or directly or indirectly applied to other related system fields, shall be equally included in the protection scope of the present invention.

Claims

1. A lower leg structure of a lower limb exoskeleton, characterized in that: It comprises a flexion / extension joint motor (1), which is mounted on the upper part of a calf structure (2), and the lower part of the calf structure (2) is rotatably connected to an ankle connection (8); The output end of the flexion / extension joint motor (1) is connected to the motor output member (4), the motor output member (4) is hinged to the upper end of the connecting rod (6), the lower end of the connecting rod (6) is hinged to the front end of the ankle connecting member (8), and the adduction / valgus joint motor (3) is installed at the rear end of the ankle connecting member (8); The flexion / extension joint motor (1) transmits power to the ankle connecting member (8) via the output member (4) and the connecting rod (6), thereby realizing the flexion / extension movement of the foot.

2. The lower leg structure of a lower limb exoskeleton according to claim 1, characterized in that: The ankle connecting member (8) is installed between the calf structural member-2 and the calf auxiliary connecting member (11) through a cross roller bearing I (9) and a cross roller bearing II (10) to form a frame structure.

3. The calf structure of a lower limb exoskeleton according to claim 2, characterized in that: It also includes a sole assembly and an ankle auxiliary connector (13); the sole assembly is mounted on the ankle connector (8) via a cross roller bearing III (12); the adduction / valgus joint motor (3) directly drives the sole assembly to rotate, thereby realizing adduction / valgus movement of the foot; one end of the ankle auxiliary connector (13) is mounted on the cross roller bearing III (12), and the other end is mounted on the ankle connector (8), forming a frame structure.

4. The lower leg structure of a lower limb exoskeleton according to claim 3, characterized in that: The sole assembly comprises an upper sole plate (14), a lower sole plate (16) and a force sensor (15); the force sensor (15) is installed between the upper sole plate (14) and the lower sole plate (16) and is used to monitor sole pressure in real time.

5. The calf structure of a lower limb exoskeleton according to any one of claims 1 to 4, characterized in that: The ankle connecting member (8) is an L-shaped structure, the connecting rod (6) and the calf structural member-2 are located on one side of the L-shaped structure, and the sole assembly is located on the other side of the L-shaped structure.

6. The lower leg structure of a lower limb exoskeleton according to claim 4, characterized in that: The rear end of the upper foot sole (14) is provided with a connecting end, and the upper foot sole (14) is mounted on the ankle connecting piece (8) by cooperating with the cross roller bearing III (12) through the hole on the connecting end.

7. The lower leg structure of a lower limb exoskeleton according to claim 6, characterized in that: The lower foot sole plate (16) and the force sensor (15) are mounted on the bottom of the upper foot sole plate (14) by means of screws.

8. The calf structure of a lower limb exoskeleton according to any one of claims 1 to 4, characterized in that: The calf structural member (2) and the calf auxiliary connecting member (11) are hollowed out to reduce weight; the calf auxiliary connecting member (11) and the ankle auxiliary connecting member (13) are respectively fixed to the calf structural member (2) and the ankle connecting member (8) by screws.

9. The lower leg structure of a lower limb exoskeleton according to claim 3, characterized in that: The upper and lower ends of the connecting rod (6) are respectively connected to the motor output member (4) and the ankle connecting member (8) through a pin assembly I (5) and a pin assembly II (7) to form a rotating pair.

10. An exoskeleton robot, characterized in that: A calf structure comprising a lower limb exoskeleton as described in any one of claims 1 to 9.

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