A bionic exoskeleton device based on the structure of the human knee joint

Abstract

The present invention discloses a bionic exoskeleton device based on the human knee joint structure, comprising a thigh connector, a lead screw, a slider, a connecting rod group, a motor and a lower limb mechanism; the lead screw is driven to rotate by the motor; the slider is connected to the lead screw by threaded cooperation to realize spiral transmission; the connecting rod group comprises a connecting rod I hinged between the slider and the thigh connector and a connecting rod II hinged between the thigh connector and the lower limb mechanism; the thigh connector is fixedly provided with a non-circular gear mechanism pinion, and the lower limb mechanism is fixedly provided with a non-circular gear mechanism large gear meshing with the non-circular gear mechanism pinion; the exoskeleton device of the present invention solves the problems of insufficient bionics and complex structure existing in existing exoskeleton devices, and has the advantages of high efficiency, high bionics, light weight and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of bionic exoskeletons, and in particular relates to a high-efficiency, high-bionics and lightweight exoskeleton device. Background Art

[0002] At present, the knee exoskeleton related products produced in my country are mainly simple passive knee exoskeletons based on single-axis or four-bar mechanisms. They have the disadvantages of single function, insufficient bionics, high energy consumption, and poor wearing experience, and cannot meet the daily life needs of the disabled. Although the single-axis knee exoskeleton has the advantage of simple structure, the movement of the human knee joint is a mixed movement of rotation and sliding, so the single-axis knee exoskeleton has the disadvantage of insufficient bionics; although the four-bar knee exoskeleton has certain bionics and stability, its structure is relatively complex, resulting in the knee exoskeleton being relatively bulky and consuming more power. Therefore, it is particularly important to design a knee exoskeleton device with low mass, high bionics, low energy consumption, and good wearing effect.

[0003] The present invention proposes a bionic exoskeleton solution based on the human knee joint structure, which realizes high bionics and high efficiency performance of the device based on the human knee joint motion curve, and adopts a partial hollow structure and a simple connecting rod motion structure to realize the low mass and low energy consumption performance of the device. The overall effect of the invented device achieves good performance of wearability, which has played a certain role in promoting the development of my country's knee joint exoskeleton field. Summary of the invention

[0004] The purpose of the present invention is to solve the problems of insufficient bionics of existing single-axis knee exoskeleton, complex and bulky structure of four-link knee exoskeleton, and high power consumption, and to propose a new solution to realize a high-performance exoskeleton device with low mass, high efficiency, high bionics and low energy consumption.

[0005] The bionic exoskeleton device based on the human knee joint structure of the present invention comprises a thigh connecting piece, a lead screw, a slider, a connecting rod group, a motor and a lower limb mechanism; the lead screw is driven to rotate by the motor; the slider is connected to the lead screw by threaded fit to realize spiral transmission; the connecting rod group comprises a connecting rod I hinged between the slider and the thigh connecting piece and a connecting rod II hinged between the thigh connecting piece and the lower limb mechanism; the thigh connecting piece is fixedly provided with a non-circular gear mechanism pinion, and the lower limb mechanism is fixedly provided with a non-circular gear mechanism large gear meshing with the non-circular gear mechanism pinion;

[0006] Further, the motor drives the lead screw to rotate through a synchronous belt transmission mechanism;

[0007] Furthermore, the lower limb mechanism includes a calf rod, a gear connecting frame fixed on the calf rod, and a motor mounting frame fixed on the gear connecting frame for fixing and mounting the motor; the large gear of the non-circular gear mechanism is arranged at the upper end of the gear connecting frame;

[0008] Furthermore, the pitch curve of the large gear of the non-circular gear mechanism is consistent with the shape of the ideal curve of rotation of the human knee joint;

[0009] Furthermore, the small gear of the non-circular gear mechanism is integrally formed at the lower end of the thigh connector, and the large gear of the non-circular gear mechanism is integrally formed at the upper end of the gear connecting frame;

[0010] Further, one end of the connecting rod II is hinged to the pinion of the non-circular gear mechanism, and the other end is hinged to the motor mounting frame;

[0011] Furthermore, a screw mounting frame is fixedly provided on one side of the motor mounting frame; the screw is supported on the screw mounting frame through a deep groove ball bearing;

[0012] Further, the motor is a brushless motor, which is fixed to the motor mounting frame with the output shaft facing downward and is coaxial with the calf rod, the output shaft of the brushless motor is connected to the small pulley shaft of the synchronous belt transmission mechanism through a coupling, and the small pulley shaft is supported on the upper end of the calf rod through a deep groove ball bearing;

[0013] Furthermore, the connecting portion between the pinion of the non-circular gear mechanism and the thigh connecting piece is a hollow structure.

[0014] Beneficial effects of the present invention:

[0015] (1) The bionic exoskeleton device of the present invention cleverly imitates the motion structure of the human knee joint, making the motion effect close to that of the human body, greatly improving the motion transmission efficiency, improving the shortcomings of the existing exoskeleton device motion bionics, improving the comfort of the wearer, and relieving the wearer's own fatigue;

[0016] (2) The bionic exoskeleton device of the present invention adopts a non-circular gear mechanism in structure. The upper end of the pinion mechanism is hollow and supported by a connecting rod. The transmission method adopts a combination of a lead screw and a synchronous pulley. The driving method adopts a non-circular gear meshing transmission, which greatly reduces the complexity of the device and reduces the weight of the device itself.

[0017] (3) The bionic exoskeleton device of the present invention has a simple structure, is easy to operate, and is easy to disassemble and install and to maintain;

[0018] (4) The pitch curve of the large gear of the non-circular gear mechanism of the present invention is consistent with the ideal curve shape of the human knee joint rotation. Therefore, the meshing movement of the small gear mechanism of the non-circular gear mechanism and the large gear of the non-circular gear mechanism is consistent with the movement of the human knee joint, with high bionics and good comfort in use. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0020] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0021] Figure 2 It is a schematic diagram of the hollow structure of the connection part between the pinion of the non-circular gear mechanism and the thigh connecting member in the present invention;

[0022] Figure 3 It is the ideal curve of the human knee joint.

[0023] Figure markings: 1-thigh connector, 2-small gear of non-circular gear mechanism, 3-connecting rod I, 4-slider, 5-screw, 6-screw mounting frame, 7-large synchronous pulley, 8-calf rod, 9-large gear of non-circular gear mechanism, 10-connecting rod II, 11-brushless motor, 12-motor mounting frame, 13-small synchronous pulley, 14-gear connecting frame. DETAILED DESCRIPTION

[0024] like Figure 1 As shown, a bionic exoskeleton device based on the human knee joint structure of this embodiment includes a thigh connector 1, a lead screw 5, a slider 4, a connecting rod group, a brushless motor 11 and a lower limb mechanism;

[0025] The upper end of the thigh connector 1 is used to connect to the end of the user's thigh, and the lower end is provided with a "J"-shaped rod, and a non-circular gear mechanism pinion 2 is integrally formed on the hook of the "J"-shaped rod;

[0026] The lower limb mechanism includes a calf rod 8, a foot mounted on the lower end of the calf rod 8, a gear connecting frame 14 fixed to the upper end of the calf rod 8, and a motor mounting frame 12 fixed to the middle of the gear connecting frame 14 for fixing and mounting the motor; the upper end of the gear connecting frame 14 is integrally formed with a non-circular gear mechanism pinion 2 meshing with the non-circular gear mechanism large gear 9;

[0027] The brushless motor 11 is fixed in the motor mounting frame 12 with the output shaft facing downward and is coaxial with the calf rod 8. The output shaft of the brushless motor 11 is connected to the axle of the small synchronous pulley 13 through a coupling, and the axle of the small synchronous pulley 13 is supported on the upper end of the calf rod 8 through a deep groove ball bearing; a screw mounting frame 6 is fixedly installed on the outer side of the motor mounting frame 12; the screw 5 is supported on the screw mounting frame 6 through a deep groove ball bearing, and a large synchronous pulley 7 is fixedly installed on the lower end; the slider 4 is connected to the screw 5 through threaded cooperation to realize spiral transmission; the connecting rod group includes connecting rod I3 and connecting rod II10; one end of the connecting rod I3 is hinged to the thigh connecting member 1, and the other end is hinged to the slider 4; One end of the connecting rod II 10 is hinged to the pinion 2 of the non-circular gear mechanism, and the other end is hinged to the motor mounting frame 12; the connecting rod I 3 is two and is arranged on both sides of the slider 4 and the pinion 2 of the non-circular gear mechanism, and both are hinged through a pin shaft; the slider 4 drives the pinion 2 of the non-circular gear mechanism to rotate through the connecting rod I 3; the connecting rod II 10 is also two and is arranged on both sides of the pinion 2 of the non-circular gear mechanism and the motor mounting frame 12, and both are hinged through a pin shaft; the connecting rod II 10 is hinged on the motor mounting frame 12 at one end to limit the pinion 2 of the non-circular gear mechanism, and the meshing rotation range of the pinion 2 of the non-circular gear mechanism and the large gear 9 of the non-circular gear mechanism is ensured by mechanical limit. The large gear 9 of the non-circular gear mechanism is fixed to the calf rod 8 of the lower limb mechanism, providing stable meshing support for the non-circular gear mechanism.

[0028] The power output by the brushless motor 11 is transmitted to the lead screw 5 through the small synchronous pulley 13 and the large synchronous pulley 7 in turn, so as to drive the lead screw 5 to rotate around its own axis, and then push the slider 4 to make a linear motion along the axis of the lead screw 5, so as to realize that the connecting rod Ⅰ3 drives the non-circular gear mechanism pinion 2 and the non-circular gear mechanism large gear 9 to mesh and rotate, and push the thigh connector 1 and the lower limb mechanism to perform a mixed motion of relative rotation and relative sliding, and finally complete the walking motion. The motion trajectory of the pinion 2 of the non-circular gear mechanism can be directly obtained through the rotation angle of the output shaft of the brushless motor 11; the axial displacement output of the brushless motor 11 is combined with the transmission mode of belt drive, gear drive, and rod drive, which simplifies the transmission mechanism of the previous exoskeleton device and reduces the weight of the mechanism; on the other hand, since the pitch curve of the non-circular gear mechanism large gear 9 is consistent with the shape of the ideal curve of the human knee joint rotation (such as Figure 3 As shown, the "ideal curve of human knee joint rotation" described in this application can be found in the "ideal knee joint instantaneous center trajectory" recorded in the following literature: Shuai Yumei, Xu Zhan, Li Shizhen, et al. Selection and optimization of multi-center knee joint mechanism [J]. Journal of Jianghan Petroleum Institute, 2001, 23(4): 86-88.), therefore, the meshing motion of the small gear mechanism 2 of the non-circular gear mechanism and the large gear 9 of the non-circular gear mechanism is consistent with the motion of the human knee joint, realizing the ideal human knee joint motion and increasing the bionics of the device.

[0029] The bottom of the motor mounting frame 12 and the screw mounting frame 6 both include deep groove ball bearings, which respectively play an axial limiting role for the brushless motor 11 and the screw 5; the motor mounting frame 12 and the screw mounting frame 6 are both made of high-strength aluminum alloy.

[0030] The transmission route of the present invention is: brushless motor 11 ── small synchronous pulley 13 ── large synchronous pulley 7 ── lead screw 5 ── slider 4 ── connecting rod I3 ── small gear 2 of non-circular gear mechanism.

[0031] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A bionic exoskeleton device based on the human knee joint structure, characterized in that: It includes a thigh connecting piece, a lead screw, a slider, a connecting rod group, a motor and a lower limb mechanism; the lead screw is driven to rotate by the motor; the slider is connected to the lead screw by threaded cooperation to realize spiral transmission; the connecting rod group includes a connecting rod I hinged between the slider and the thigh connecting piece and a connecting rod II hinged between the thigh connecting piece and the lower limb mechanism; the thigh connecting piece is fixedly provided with a non-circular gear mechanism pinion, and the lower limb mechanism is fixedly provided with a non-circular gear mechanism large gear meshing with the non-circular gear mechanism pinion; the connecting rod I is two and is separately arranged on both sides of the slider and the non-circular gear mechanism pinion, and both are hinged by a pin shaft; the slider drives the non-circular gear mechanism pinion mechanism to rotate through the connecting rod I; the connecting rod II is also two and is separately arranged on both sides of the non-circular gear mechanism pinion and the motor mounting frame, and both are hinged by a pin shaft; The motor drives the lead screw to rotate through the synchronous belt transmission mechanism, thereby pushing the slider to perform linear motion along the lead screw axis, so that the connecting rod I drives the small gear of the non-circular gear mechanism to mesh with the large gear of the non-circular gear mechanism, and pushes the thigh connecting piece and the lower limb mechanism to perform a mixed motion of relative rotation and relative sliding, and finally completes the walking motion; The lower limb mechanism comprises a calf rod, a gear connecting frame fixed on the calf rod, and a motor mounting frame fixed on the gear connecting frame for fixing and mounting the motor; the large gear of the non-circular gear mechanism is arranged on the upper end of the gear connecting frame; The small gear of the non-circular gear mechanism is integrally formed at the lower end of the thigh connecting member, and the large gear of the non-circular gear mechanism is integrally formed at the upper end of the gear connecting frame; One end of the connecting rod II is hinged to the pinion of the non-circular gear mechanism, and the other end is hinged to the motor mounting frame.

2. The bionic exoskeleton device based on the human knee joint structure according to claim 1, characterized in that: The pitch curve of the large gear of the non-circular gear mechanism is consistent with the shape of an ideal curve of rotation of the human knee joint.

3. The bionic exoskeleton device based on the human knee joint structure according to claim 1, characterized in that: A lead screw mounting frame is fixedly arranged on one side of the motor mounting frame; the lead screw is supported on the lead screw mounting frame through a deep groove ball bearing.

4. The bionic exoskeleton device based on the human knee joint structure according to claim 1, characterized in that: The motor is a brushless motor, which is fixed to the motor mounting frame with the output shaft facing downward and remains coaxial with the calf rod. The output shaft of the brushless motor is connected to the small pulley shaft of the synchronous belt transmission mechanism through a coupling, and the small pulley shaft is supported on the upper end of the calf rod through a deep groove ball bearing.

5. The bionic exoskeleton device based on the human knee joint structure according to claim 1, characterized in that: The connecting portion between the pinion of the non-circular gear mechanism and the thigh connecting piece is a hollow structure.

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