Five-connecting-rod knee joint exoskeleton device

Abstract

The invention relates to the related technical field of the fields of man-machine cooperation, rehabilitation assistive devices and wearable robots, in particular to a five-connecting-rod knee joint exoskeleton device which comprises a thigh assembly (1), a transmission assembly (2) and a shank assembly (3), and the thigh assembly (1) comprises an output motor (101), a power output rod (102), a thigh binding piece (103), a thigh sliding block (104) and a thigh guide rod (105). The transmission assembly (2) comprises a first connecting rod (201), a second connecting rod (202), a third connecting rod (203), a fourth connecting rod (204), a fifth connecting rod (205) and an auxiliary connecting rod (206), and the shank assembly (3) comprises a shank binding piece (301), a shank sliding block (302), a shank guide rod (303) and a sensing unit (304). The five-connecting-rod knee joint exoskeleton device is based on the mechanical structure design of a five-connecting-rod mechanism, advanced control strategies such as multi-sensor fusion and impedance control are combined, and the nonlinear track of a sliding rotation center in the bending and stretching process of the knee joint of the human body is highly fitted in kinematics; meanwhile, the exoskeleton can adaptively provide assistance or damping according to the gait characteristics and the motion intention of the user by adjusting the output torque and flexibility in real time on the aspect of dynamic control, so that the naturalness, comfort and safety of man-machine interaction are effectively improved; therefore, diversified application requirements of rehabilitation training, walking assistance, man-machine cooperation and the like can be better met.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of human-computer collaboration, rehabilitation aids and wearable robots, in particular to a five-link knee exoskeleton device. BACKGROUND

[0002] With the aggravation of social aging and the improvement of people's living standards, the population with disabilities caused by stroke, spinal cord injury, brain trauma and traffic accidents has grown rapidly, resulting in some patients being unable to walk like ordinary people due to knee joint disease. In recent years, human society has developed towards high automation, informatization and mechanization, and robots have a deeper and deeper impact on human life. As part of the exoskeleton robot, the exoskeleton knee joint can provide the knee joint walking power required for gait walking for the elderly, patients with knee joints or other people in need.

[0003] Currently, the traditional single-joint-driven or simplified linkage mechanism knee exoskeleton often cannot accurately reproduce the complex non-circular center motion trajectory of the knee joint, which easily causes joint constraint discomfort, insufficient coordination and other problems, limiting the performance of the exoskeleton in human-computer coupling and motion assistance. Therefore, users have higher demands for knee exoskeleton, requiring it not only to realize natural human motion trajectory matching, but also to have the characteristics of lightweight, high comfort and high adaptability. SUMMARY

[0004] The purpose of the present application is to provide a five-link knee exoskeleton device to solve the problem that the traditional single-joint-driven or simplified linkage mechanism knee exoskeleton often cannot accurately reproduce the complex non-circular center motion trajectory of the knee joint, which easily causes joint constraint discomfort, insufficient coordination and other problems, limiting the performance of the exoskeleton in human-computer coupling and motion assistance.

[0005] To achieve the above purpose, the present application provides the following technical scheme: a five-link knee exoskeleton device, comprising a thigh assembly, a transmission assembly and a shank assembly, characterized in that: the external power part of the thigh assembly is rotationally connected with the transmission assembly, and the middle part guide rod is tightly connected with the transmission assembly; the transmission assembly is tightly connected with the guide rod of the shank assembly.

[0006] Further, the thigh assembly comprises an output motor, a power output rod, a thigh binding piece, a thigh sliding block, a thigh guide rod, the output motor is rotationally connected with the power output rod, and the power output rod is rotationally connected with the transmission assembly; the output motor is tightly connected with the thigh binding piece through threads, the thigh binding piece is tightly connected with the thigh sliding block, the thigh sliding block is slidingly connected with the thigh guide rod, and the thigh guide rod is tightly connected with the transmission assembly.

[0007] Further, the transmission assembly comprises a first connecting rod, a second connecting rod, a third connecting rod, a fourth connecting rod, a fifth connecting rod and an auxiliary connecting rod, one side of the first connecting rod is rotationally connected with the second connecting rod, the other side is rotationally connected with a third node of the fifth connecting rod, the other side of the second connecting rod is rotationally connected with the third connecting rod and the auxiliary connecting rod, the other side of the third connecting rod is rotationally connected with the fourth connecting rod, the other side of the fourth connecting rod is rotationally connected with a second node of the fifth connecting rod, the fourth node of the fifth connecting rod is rotationally connected with the other side of the auxiliary connecting rod, and a first node is rotationally connected with the thigh assembly, and the tail end of the first connecting rod is fixedly connected with the lower leg assembly.

[0008] Further, the lower leg assembly comprises a lower leg binding member, a lower leg sliding block, a lower leg guide rod and a sensing unit, one side of the lower leg guide rod is fixedly connected with the transmission assembly, and the other side is slidingly connected with the lower leg sliding block, and the lower leg sliding block is fixedly connected with the lower leg binding member.

[0009] Further, the sensing unit is fixedly connected with the first connecting rod.

[0010] Further, the output shaft of the output motor is provided with a torque sensor, and the sensing unit comprises a gyroscope, an accelerometer, a torque sensor and various sensors.

[0011] Compared with the prior art, the beneficial effects of the present application are: The technical scheme adopts a mechanical structure design based on a five-connecting-rod mechanism, combines advanced control strategies such as multi-sensor fusion and impedance control, not only highly fits the nonlinear trajectory of the sliding rotation center in the flexion and extension process of the human knee joint in kinematics, but also adjusts the output torque and flexibility in real time in dynamics control, so that the exoskeleton can adaptively provide assistance or damping according to the gait characteristics and motion intention of the user, effectively improving the naturalness, comfort and safety of human-computer interaction, and thus better meeting the diversified application requirements of rehabilitation training, walking assistance and human-computer collaboration. BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 It is a side appearance structure schematic view of the present application; Figure 2 It is a front structure schematic view of the present application; Figure 3 It is a back structure schematic view of the present application; Figure 4 It is a structure schematic view of the present application in each state; Figure 5 It is a topological relationship principle schematic view of the present application.

[0013] In the figure: 1, thigh assembly; 101, output motor; 102, power output rod; 103, thigh binding piece; 104, thigh sliding block; 105, thigh guide rod; 2, transmission assembly; 201, first connecting rod; 202, second connecting rod; 203, third connecting rod; 204, fourth connecting rod; 205, fifth connecting rod; 206, auxiliary connecting rod; 3, shank assembly; 301, shank binding piece; 302, shank sliding block; 303, shank guide rod; 304, sensing unit. DETAILED DESCRIPTION

[0014] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0015] Please refer to Figures 1-5 The present application provides a technical solution: a five-connecting-rod knee exoskeleton device, comprising a thigh assembly 1, a transmission assembly 2 and a shank assembly 3, characterized in that: the external power part of the thigh assembly 1 is rotationally connected with the transmission assembly 2, and the middle part guide rod is fastened with the transmission assembly 2; the transmission assembly 2 is fastened with the guide rod of the shank assembly 3.

[0016] Further, the thigh assembly 1 comprises an output motor 101, a power output rod 102, a thigh binding piece 103, a thigh sliding block 104 and a thigh guide rod 105, the output motor 101 is rotationally connected with the power output rod 102, and the power output rod 102 is rotationally connected with the transmission assembly 2; the output motor 101 is fastened with the thigh binding piece 103 through threads, the thigh binding piece 103 is fastened with the thigh sliding block 104, the thigh sliding block 104 is slidingly connected with the thigh guide rod 105, and the thigh guide rod 105 is fastened with the transmission assembly 2.

[0017] Further, the transmission assembly 2 comprises a first connecting rod 201, a second connecting rod 202, a third connecting rod 203, a fourth connecting rod 204, a fifth connecting rod 205, and an auxiliary connecting rod 206. One side of the first connecting rod 201 is rotationally connected with the second connecting rod 202, and the other side is rotationally connected with a third node of the fifth connecting rod 205. The other side of the second connecting rod 202 is rotationally connected with the third connecting rod 203 and the auxiliary connecting rod 206. The other side of the third connecting rod 203 is rotationally connected with the fourth connecting rod 204. The other side of the fourth connecting rod 204 is rotationally connected with a second node of the fifth connecting rod 205. The fourth node of the fifth connecting rod 205 is rotationally connected with the other side of the auxiliary connecting rod 206. A first node is rotationally connected with the thigh assembly 1. The tail end of the first connecting rod 201 is fixedly connected with the lower leg assembly 3.

[0018] Further, the lower leg assembly 3 comprises a lower leg binding member 301, a lower leg slider 302, a lower leg guide rod 303, and a sensing unit 304. One side of the lower leg guide rod 303 is fixedly connected with the transmission assembly 2, and the other side is slidingly connected with the lower leg slider 302. The lower leg slider 302 is fixedly connected with the lower leg binding member 301.

[0019] Further, the sensing unit 304 is fixedly connected with the first connecting rod 201.

[0020] Further, the output shaft of the output motor 101 is provided with a torque sensor. The sensing unit 304 comprises a gyroscope, an accelerometer, a torque sensor, and various sensors.

[0021] When the five-connecting-rod knee exoskeleton device of the present example is in operation, its working principle can be divided into two typical operating modes, namely, impedance control mode and assistance mode.

[0022] 1. Impedance control mode When the user actively bends, the lower leg drives the lower leg binding member 301 to rotate counterclockwise around the knee joint, further drives the lower leg slider 302 to rotate counterclockwise around the knee joint, and the lower leg slider 302 drives the lower leg guide rod 303 to rotate around the knee joint, thereby causing the first connecting rod 201 to rotate counterclockwise around the knee joint. Since the nodes of the first connecting rod 201, the second connecting rod 202, the third connecting rod 203, the fourth connecting rod 204, the fifth connecting rod 205, and the auxiliary connecting rod 206 are rotationally connected, the rotation of the first connecting rod 201 around the knee joint drives the rotation of each connecting rod, and finally causes the first node of the fifth connecting rod 205 to move counterclockwise around the knee joint. The power output rod 102 drives the output motor to rotate counterclockwise. See Figure 4The torque sensor in the perception unit 304 and the output motor 102 will transmit the detected motion speed, angle and joint external force to the controller, which can adjust the output torque of the output motor 102 and the system stiffness, damping and other parameters in time to produce flexible following or damping effect on the motion.

[0023] In this mode, the five-bar linkage knee exoskeleton device does not provide active driving force, but reduces joint friction, buffers impact or restricts accidental large amplitude motion by adjusting its mechanical impedance, thereby enhancing the comfort and safety of the user.

[0024] 2. Assisted mode: Taking knee bending as an example, the output motor 102 rotates counterclockwise according to the torque given by the controller, drives the power output rod 102 to move downward, and then drives the first node of the fifth link 205 to rotate counterclockwise around the knee joint. Since the nodes of the first link 201, the second link 202, the third link 203, the fourth link 204, the fifth link 205 and the auxiliary link 206 are connected, the counterclockwise rotation of the first node of the fifth link 205 around the knee joint will eventually cause the counterclockwise rotation of the first link 201 around the knee joint, and then cause the counterclockwise rotation of the calf binding member 301 around the knee joint, as shown in Figure 4 The user is passively bent.

[0025] In this mode, the five-bar linkage knee exoskeleton device is based on the typical torque curve required by the natural flexion and extension motion of the knee joint during human walking, and pre-sets a target assist torque model that changes with the gait phase. The system reads the knee joint angle and angular velocity information measured by the perception unit 304 in real time to determine the current gait stage, and combines the torque sensor feedback to calculate the expected assist torque required by the current output in real time, realizes flexible assist consistent with the natural flexion and extension motion of the human body, and makes the user obtain obvious labor-saving effect and comfortable experience in the scene of walking, uphill or downhill walking, etc.

[0026] Although embodiments of the present application have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and alterations can be made thereto without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A five-link knee joint exoskeleton device, comprising a thigh assembly (1), a transmission assembly (2), and a lower leg assembly (3), characterized in that: The external power part of the thigh assembly (1) is rotatably connected to the transmission assembly (2), and the guide rod in the middle part is fastened to the transmission assembly (2); the transmission assembly (2) is fastened to the guide rod of the lower leg assembly (3).

2. The five-link knee joint exoskeleton device according to claim 1, characterized in that: The thigh assembly (1) includes an output motor (101), a power output rod (102), a thigh binding (103), a thigh slider (104), and a thigh guide rod (105). The output motor (101) is rotatably connected to the power output rod (102), and the power output rod (102) is rotatably connected to the transmission assembly (2). The output motor (101) is fastened to the thigh binding (103) by threads, the thigh binding (103) is fastened to the thigh slider (104), the thigh slider (104) is slidably connected to the thigh guide rod (105), and the thigh guide rod (105) is fastened to the transmission assembly (2).

3. The five-link knee joint exoskeleton device according to claim 1, characterized in that: The transmission assembly (2) includes a first link (201), a second link (202), a third link (203), a fourth link (204), a fifth link (205), and an auxiliary link (206). The first link (201) is rotatably connected to the second link (202) on one side and to the third node of the fifth link (205) on the other side. The second link (202) is rotatably connected to the third link (203) and the auxiliary link (206) on the other side. The third link (203) is rotatably connected to the fourth link (204) on the other side. The fourth link (204) is rotatably connected to the second node of the fifth link (205) on the other side. The fourth node of the fifth link (205) is rotatably connected to the other side of the auxiliary link (206). The first node is rotatably connected to the thigh assembly (1). The tail end of the first link (201) is fastened to the calf assembly (3).

4. The five-link knee joint exoskeleton device according to claim 1, characterized in that: The lower leg assembly (3) includes a lower leg binding member (301), a lower leg slider (302), a lower leg guide rod (303), and a sensing unit (304). One side of the lower leg guide rod (303) is fastened to the transmission assembly (2), and the other side is slidably connected to the lower leg slider (302). The lower leg slider (302) is fastened to the lower leg binding member (301).

5. The five-link knee joint exoskeleton device according to claim 3 or 4, characterized in that: The sensing unit (304) is fastened to the first link (201).

6. The five-link knee exoskeleton device according to claim 2 or 4, characterized in that: The output motor (101) is equipped with a torque sensor on its output shaft, and the sensing unit (304) includes various sensors such as gyroscope, accelerometer, and torque sensor.

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