Lower-limb-powered exoskeleton device for rehabilitation assistance

Abstract

Disclosed in the present invention is a lower-limb-powered exoskeleton device for rehabilitation assistance, comprising ankle-joint sagittal-plane driving units, knee-joint sagittal-plane driving units, hip-joint sagittal-plane driving units, a hip-joint horizontal-plane driving unit, a joint driver connecting frame, a lower-limb fixing support, sensors, a controller and a power supply. Antagonistic-drive-type linear driving units are used in the sagittal plane of a hip joint so as to enable the bending and extension movements of the hip joint, and a linear driving unit having the function of self-locking when powered off is used in the horizontal plane of the hip joint so as to enable the turning movements of the exoskeleton; and a linear driving unit in cooperation with a magnetorheological brake is used in the sagittal plane of each knee joint, thereby significantly reducing the power consumption of a knee-joint driver while lowering the control difficulty. The powered exoskeleton device can help patients with an impaired lower-limb motor function to carry out walking rehabilitation training.

Description

Lower limb powered exoskeleton device for rehabilitation assistance TECHNICAL FIELD

[0001] The present application belongs to the technical field of lower limb exoskeleton devices, and relates to a lower limb powered exoskeleton device for rehabilitation assistance. BACKGROUND

[0002] Due to stroke, brain injury, spinal cord injury and physiological or pathological aging, patients with nervous system diseases or the elderly have different degrees of motor dysfunction, and the quality of life is significantly reduced. Therefore, there is a large demand for motor rehabilitation for people with motor dysfunction.

[0003] In order to meet the needs of the above-mentioned population, researchers and rehabilitation medical companies have developed many lower limb rehabilitation exoskeleton devices to help people with impaired motor function, such as stroke patients and the elderly, to perform rehabilitation training. However, the existing lower limb rehabilitation exoskeleton devices have many problems, and there is a big difference between the engineering practicability and the wearer's expectations, which leads to the fact that the lower limb exoskeleton cannot be widely popularized and applied.

[0004] The existing lower limb exoskeleton is out of balance between flexibility and weight. For example, in order to increase flexibility, more driving devices are added, which makes the overall mass of the lower limb rehabilitation exoskeleton too large, and requires professional help to wear, which makes the user unable to use the lower limb exoskeleton device independently, and affects the time and comfort of the wearer, and the motor rehabilitation effect is not ideal. Some lower limb exoskeleton rehabilitation robots cannot help users complete complex movements to reduce the flexibility of users using the lower limb exoskeleton. Most of the existing lower limb exoskeletons cannot actively realize the turning walking function, which will obviously reduce the user experience and practicability of the wearer in daily life,

[0005] SUMMARY

[0006] Therefore, the present application provides a lower limb powered exoskeleton device for rehabilitation assistance. According to the movement characteristics of each joint of the lower limb, an intelligent joint driver is proposed by using bionic design, which greatly reduces the power consumption of the joint driver, simplifies the mass and control difficulty of the controller, and improves the engineering practicability of the device. At the same time, the present application improves the active turning of the lower limb exoskeleton, and realizes the turning movement of the exoskeleton by introducing the degree of freedom and the corresponding driver in the horizontal plane.

[0007] In order to solve the above problems, the embodiment of the present application provides a lower limb powered exoskeleton device for rehabilitation assistance, which is characterized by comprising:

[0008] A sagittal plane driving unit of the ankle joint, which is one of an active driving unit, a semi-passive driving unit and a passive driving unit, and realizes joint driving of the ankle joint in the sagittal plane;

[0009] A sagittal plane driving unit of the knee joint, which is one of an active driving unit and a semi-passive driving unit, and realizes joint driving of the knee joint in the sagittal plane;

[0010] A sagittal plane driving unit of the hip joint, which is an active driving unit, and realizes joint driving of the hip joint in the sagittal plane;

[0011] A horizontal plane driving unit of the hip joint, which is an active driving unit and a passive driving unit, and realizes joint driving of the hip joint in the horizontal plane;

[0012] A joint driver connecting frame, which includes a waist connecting frame, a thigh connecting frame and a shank connecting frame, and connects and fixes the sagittal plane driving unit of the ankle joint, the sagittal plane driving unit of the knee joint, the sagittal plane driving unit of the hip joint and the horizontal plane driving unit of the hip joint;

[0013] A lower limb fixing support, which includes a waist fixing support, a thigh fixing support, a shank fixing support and a foot fixing support, and is used for fixing the waist, the lower limb thigh, the shank and the foot plate of a wearer of the exoskeleton device to the exoskeleton device;

[0014] A sensor, which is installed on the exoskeleton device and the wearer of the exoskeleton device, and is used for detecting the motion state of the exoskeleton and decoding the motion intention of the wearer of the exoskeleton;

[0015] A controller, which is used for controlling the motion angle, the angular velocity and the output torque of the sagittal plane driving unit of the ankle joint, the sagittal plane driving unit of the knee joint, the sagittal plane driving unit of the hip joint and the horizontal plane driving unit of the hip joint;

[0016] A power supply, which is used for supplying power to the driving units, the sensor and the controller of the exoskeleton device.

[0017] Further, the waist fixing support is fixed on the waist connecting frame, the thigh fixing support is fixed on the thigh connecting frame, the shank fixing support is fixed on the shank connecting frame, and the foot fixing support is connected to the shank connecting frame through the sagittal plane driving unit of the ankle joint.

[0018] Further, the waist connecting frame and the thigh connecting frame are connected through one of a planar hinge and a spherical hinge, and the thigh connecting frame and the shank connecting frame are connected through a planar hinge.

[0019] Further, the hip joint sagittal plane driving unit is driven by two antagonistically arranged linear drives, the linear drives contain DC motors, the DC motors cooperate with threaded rod transmission, while having displacement feedback and force feedback, the linear drives form a crank slider structure with the waist connecting frame and the thigh connecting frame, the rotation angle, angular velocity and joint torque of the hip joint in the sagittal plane can be actively controlled.

[0020] Further, the hip joint horizontal plane driving unit is an active driving unit, the driving unit is driven by two antagonistically arranged linear drives, the linear drives contain DC motors, the DC motors cooperate with threaded rod transmission, while having displacement feedback and force feedback, the linear drives form a crank slider structure with the waist connecting frame and the thigh connecting frame, the rotation angle, angular velocity and joint torque of the hip joint in the horizontal plane can be actively controlled, the turning motion is realized, the threaded rod transmission has the motor power-off self-locking function.

[0021] Further, the hip joint horizontal plane driving unit is a passive driving unit, the passive driving unit is driven by a return spring, the waist connecting frame and the thigh connecting frame can return to the initial relative position, the exoskeleton device can realize rotation in the horizontal plane under the active driving of the exoskeleton device wearer.

[0022] The return spring in the passive driving unit is one of a linear spring, a torsional spring and a pneumatic spring.

[0023] Further, the knee joint sagittal plane driving unit is an active driving unit, the driving unit is driven by two antagonistically arranged linear drives, the linear drives contain DC motors, the DC motors cooperate with threaded rod transmission, while having displacement feedback and force feedback, the linear drives form a crank slider structure with the thigh connecting frame and the shank connecting frame, the rotation angle, angular velocity and joint torque of the knee joint in the sagittal plane can be actively controlled.

[0024] Further, the knee joint sagittal plane driving unit is an active driving unit, the driving unit is driven by two antagonistically arranged linear drives, the linear drives contain DC motors, the DC motors cooperate with threaded rod transmission, while having displacement feedback and force feedback, the linear drives form a crank slider structure with the thigh connecting frame and the shank connecting frame, the rotation angle, angular velocity and joint torque of the knee joint in the sagittal plane can be actively controlled.

[0025] Further, the knee sagittal plane driving unit is a semi-passive driving unit, which is driven by a magnetic control damper cooperating with a return spring. The return spring can drive the knee to return to the initial position in the sagittal plane. The magnetic control damper and the thigh connecting frame and the lower leg connecting frame form a crank slider structure. By controlling the excitation current of the magnetic control damper, the rotation angle, angular velocity and joint torque of the knee in the sagittal plane bending and stretching can be passively controlled.

[0026] Further, the ankle sagittal plane driving unit is an active driving unit, which is composed of one of a DC motor, a gear reducer and a harmonic reducer. The active driving unit can actively control the rotation angle, angular velocity and output torque of the ankle in the sagittal plane.

[0027] Further, the ankle sagittal plane driving unit is a semi-passive unit, which is driven by a magnetic control damper cooperating with a return spring. The return spring can drive the knee to return to the initial position in the sagittal plane. The magnetic control damper and the thigh connecting frame and the lower leg connecting frame form a crank slider structure. By controlling the excitation current of the magnetic control damper, the rotation angle, angular velocity and joint torque of the knee in the sagittal plane bending and stretching can be passively controlled.

[0028] Further, the ankle sagittal plane driving unit is a passive driving unit, which is composed of a return spring. The return spring can help the relative angle of the lower leg connecting frame and the foot palm fixed support to return to the initial position. The lower leg connecting frame and the foot palm fixed support are connected through a planar hinge.

[0029] The return spring in the passive driving unit is one of a linear spring, a torsional spring and a pneumatic spring.

[0030] Further, the lower limb fixed support is used to fix the lower limb exoskeleton device and the wearer of the lower limb exoskeleton device. In order to improve the wearing comfort, the fixed support is firm, and the contact stress concentration is reduced. The lower limb fixed support is prepared by using a negative Poisson's ratio intelligent structure unit in a part of the force bearing area.

[0031] Further, the inner surface of the lower limb fixed support is integrated with a curved surface pressure measuring unit. The pressure measuring unit measures the contact stress between the lower limb exoskeleton device and the wearer of the lower limb exoskeleton device. The measured contact stress can be used to quantify the wearing comfort of the lower limb fixed support, and can also be used to decode the motion intention of the wearer of the lower limb exoskeleton.

[0032] Further, the sensor comprises a lower limb electromyography sensor (EMG), a joint angle sensor, a pressure sensor distributed on the lower limb fixing support, a pressure measuring unit distributed on the lower limb fixing support, and an inertial measurement unit (IMU) installed on the lower limb sole, calf, thigh and waist.

[0033] Further, the lower limb electromyography sensor (EMG) is used to detect the electromyography signal of the muscle of the lower limb exoskeleton wearer, thereby decoding the motion intention of the wearer, quantifying the rehabilitation effect of the wearer, and detecting the muscle movement fatigue of the lower limb and the like.

[0034] The pressure measuring unit distributed on the lower limb fixing support is used to detect the interaction force and torque between the above-mentioned exoskeleton and the wearer's limb, including the interaction force and torque between the fixing support and the user's thigh and calf, and the interaction force and torque between the user's metatarsal bottom and the lower limb exoskeleton foot bottom support plate; the inertial measurement unit is used to feedback the motion information of the lower limb exoskeleton device, including the motion direction, motion speed, motion acceleration, angle and angular velocity.

[0035] The controller identifies the motion intention of the user based on the signals obtained by the angle sensor, pressure sensor and electromyography signal detection sensor, and further controls the output torque of each direct current motor and damper of the lower limb exoskeleton device, so as to control the motion trajectory and motion posture of the hip joint, knee joint, ankle joint, thigh structure and calf structure of the lower limb exoskeleton device.

[0036] The pressure sensor is installed to the inner side of the fixing support and the foot bottom support plate, and is used to measure the interaction force between the user and the fixing support and the interaction force between the user and the ground.

[0037] The controller is used to control the hip joint, knee joint and ankle joint of the lower limb exoskeleton device to rotate according to the set direction, angle, angular velocity and angular acceleration, control the thigh structure and calf structure to swing according to the set posture, and control the interaction force and torque between the fixing support and the wearer of the lower limb exoskeleton device.

[0038] Compared with the prior art, the lower limb power exoskeleton device for rehabilitation assistance has at least the following beneficial effects:

[0039] 1) The lower limb power exoskeleton device is used to help the lower limb movement function impaired patients, such as lower limb stroke patients, to realize walking rehabilitation training, so that each joint of the lower limb realizes corresponding movement function, provides assistance to the patients, and makes the patients more easily complete standing, walking, turning around, sitting down and the like;

[0040] 2) The lower limb power exoskeleton device is designed according to the movement characteristics of each joint of the lower limb, and an intelligent joint driver is provided through bionic design, so that the power consumption of the joint driver is greatly reduced, the mass and control difficulty of the controller are simplified, and the engineering practicality of the device is improved. Meanwhile, the active turning of the lower limb exoskeleton is improved, and the turning movement of the exoskeleton is realized through the introduction of a degree of freedom and a corresponding driver in the horizontal plane.

[0041] 3) The sagittal plane of the hip joint of the lower limb power exoskeleton device adopts an antagonistic driving linear driving unit to realize the flexion and extension movement of the hip joint, the horizontal plane of the hip joint adopts a linear driving unit with a power-off self-locking function to realize the turning movement of the exoskeleton, and the sagittal plane of the knee joint adopts a linear driving unit cooperating with a magneto-rheological brake. This driving mode can obviously reduce the power consumption of the knee joint driver and simplify the control difficulty. In addition, in order to improve the man-machine interaction performance of the exoskeleton device and the wearer, the lower limb fixing support of the exoskeleton is improved, and an intelligent structure unit and a curved surface stress detection are introduced. The power exoskeleton device is mainly used for helping patients with impaired lower limb movement function, such as lower limb stroke patients, to realize walking rehabilitation training.

[0042] The above description is only a summary of the technical scheme of the present application. In order to more clearly understand the technical means of the present application and can be implemented according to the content of the specification, the following will be described in detail with the preferred embodiments of the present application and with the help of the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0043] In order to more clearly illustrate the technical scheme of the embodiments of the present application, the following will briefly introduce the drawings needed in the embodiment description. Obviously, the drawings in the following description are some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without creating any creative labor.

[0044] Fig. 1 is a schematic diagram of the front overall structure of the present application;

[0045] Fig. 2 is a schematic diagram of the back overall structure of the present application;

[0046] Fig. 3 is a schematic diagram of the side overall structure of the present application;

[0047] Fig. 4 is a schematic diagram of the hip joint horizontal plane active driving unit structure in the present application;

[0048] Fig. 5 is a schematic diagram of the hip joint horizontal plane passive driving unit structure in the present application;

[0049] Fig. 6 is a schematic diagram of the hip joint sagittal plane active driving unit structure and movement in the present application;

[0050] Fig. 7 is a schematic diagram of the knee joint sagittal plane active driving unit structure in the present application;

[0051] Figure 8 is a schematic diagram of the passive driving unit structure of the knee joint in the sagittal plane of the present application;

[0052] Figure 9 is a schematic diagram of the active driving unit structure of the ankle joint in the sagittal plane of the present application;

[0053] Figure 10 is a schematic diagram of the semi-passive driving unit structure of the ankle joint in the sagittal plane of the present application;

[0054] Figure 11 is a schematic diagram of the passive driving unit structure of the ankle joint in the sagittal plane of the present application;

[0055] Figure 12 is a schematic diagram of the lower leg fixation support of the present application;

[0056] Figure 13 is a schematic diagram of the linear actuator structure of the present application;

[0057] Figure 14 is a schematic diagram of the magneto-rheological damper structure of the present application;

[0058] Figure 15 is a schematic diagram of the return spring actuator structure of the present application;

[0059] Figure 16 is a schematic diagram of the motion of the lower limb powered exoskeleton device for rehabilitation assistance in a complete gait cycle;

[0060] Figure 17 is a schematic diagram of the changes in the sagittal plane angles of the hip joint, knee joint and ankle joint in a complete gait cycle of the human body (walking on a force plate);

[0061] Figure 18 is a schematic diagram of the changes in the joint torque of the hip joint, knee joint and ankle joint in a complete gait cycle of the human body (walking on a force plate);

[0062] Figure 19 is a schematic diagram of the changes in the joint power of the hip joint, knee joint and ankle joint in a complete gait cycle of the human body (walking on a force plate);

[0063] Figure 20 is a schematic diagram of the changes in the reaction force of the force plate in a gait cycle of the human body (normal person walking on a force plate);

[0064] Wherein: 1, control backpack; 2, waist fixation support; 3, thigh fixation support; 4, third DC motor 4; 5, seventh DC motor; 6, calf fixation support; 7, ninth DC motor; 8, fifth DC motor; 9, eighth DC motor; 10, tenth DC motor; 11, first DC motor; 12, fourth DC motor; 13, first magneto-rheological damper; 14, second DC motor; 15, sixth DC motor; 16, second magneto-rheological damper; 17, position limiter; 18, threaded screw; 19, force sensor; 20, magneto-rheological fluid valve; 21, magneto-rheological fluid guide pipe; 22, hydraulic cylinder; 23, return spring; 24, flexible pressure sensor; 25, negative Poisson's ratio intelligent structure unit. DETAILED DESCRIPTION

[0065] In order to make the purposes, technical solutions and advantages of the present application clearer, the present application is further described in detail below in combination with the drawings and examples. It should be understood that the specific examples described herein are only used to explain the present application and are not used to limit the present application. The present application is intended to be more generally applied to rehabilitation exoskeleton robots, and thus the present application can be used in any practical application having any requirements suitable for specific applications.

[0066] The present application provides a lower limb powered exoskeleton device for rehabilitation assistance, and the hardware part of the lower limb exoskeleton device comprises a hip joint horizontal plane driving unit, a hip joint sagittal plane driving unit, a knee joint sagittal plane driving unit, an ankle joint sagittal plane driving unit, a joint driver connecting frame, a lower limb fixing support, a sensor, a controller and a power supply.

[0067] The ankle joint sagittal plane driving unit is used to realize the joint driving of the ankle joint in the sagittal plane; the knee joint sagittal plane driving unit is used to realize the joint driving of the knee joint in the sagittal plane; the hip joint sagittal plane driving unit is used to realize the joint driving of the hip joint in the sagittal plane; and the hip joint horizontal plane driving unit is used to realize the joint driving of the hip joint in the horizontal plane.

[0068] The joint driver connecting frame comprises a waist connecting frame, a thigh connecting frame and a shank connecting frame, and the joint driver connecting frame connects and fixes the ankle joint sagittal plane driving unit, the knee joint sagittal plane driving unit, the hip joint sagittal plane driving unit and the hip joint horizontal plane driving unit.

[0069] The lower limb fixing support comprises a waist fixing support, a thigh fixing support, a shank fixing support and a foot sole fixing support, and the lower limb fixing support is used to fix the waist, the lower limb thigh, the lower limb shank and the foot sole of the wearer of the exoskeleton device and the exoskeleton device. The sensor is installed on the exoskeleton device and the wearer of the exoskeleton device, and is used to detect the motion state of the exoskeleton and decode the motion intention of the wearer of the exoskeleton; the controller is used to control the motion angle, the angular velocity and the output torque of the ankle joint sagittal plane driving unit, the knee joint sagittal plane driving unit, the hip joint sagittal plane driving unit and the hip joint horizontal plane driving unit; and the power supply is used to power the driving units, the sensor and the controller of the exoskeleton device.

[0070] Specifically, referring to FIG. 1, the control backpack 1 is installed to the fixed position of the back support plate through a connecting piece, and the control backpack is provided with a signal processing module, a controller, a driving module and a power supply. The back support plate is fixed on the waist fixing support 2.

[0071] As a preferred embodiment of the present application, the hip joint horizontal plane driving unit can be an active driving unit or a passive driving unit,

[0072] Specifically, referring to FIG. 2 and FIG. 4, when the hip joint horizontal plane driving unit is an active driving unit, the hip joint horizontal plane active driving unit is composed of two antagonistically arranged linear drives, referring to FIG. 13, the two linear drives are respectively composed of a first DC motor 11 cooperating with a threaded screw rod 18 transmission and a second DC motor 14 cooperating with a threaded screw rod 18 transmission, the linear drives are connected with the waist fixed support 2 and the waist connecting frame through joint bearings respectively, forming a crank slider structure, the rotational torque or holding torque dynamically output by the first DC motor 11 and the second DC motor 14 is transmitted through the threaded screw rod 18, for driving the hip joint horizontal plane of the lower extremity exoskeleton device to perform the internal rotation and abduction movement, or maintaining the standing locking state of the hip joint horizontal plane of the wearer, actively controlling the rotation angle, angular velocity and joint torque of the above-mentioned hip joint horizontal plane. For example, when the stroke patient wearing the above-mentioned lower extremity exoskeleton device turns to the right, the first DC motor 11 rotates forward to provide a rotational torque, which drives the hip joint on one side of the lower extremity exoskeleton device to rotate outward in the horizontal plane through forward linear displacement of the threaded screw rod 18, and the second DC motor 14 rotates reversely to provide a reverse rotational torque, which drives the hip joint on the other side of the lower extremity exoskeleton device to rotate inward in the horizontal plane through reverse linear displacement of the threaded screw rod 18, so as to control the exoskeleton hip joint to rotate to a predetermined position in the horizontal plane, and in the rotation process, the user is provided with motion assistance through the waist fixed support of the lower extremity exoskeleton device, helping the user to complete the turning action.

[0073] Specifically, referring to FIG. 5 and FIG. 15, when the hip joint horizontal plane driving unit is a passive driving unit, the passive driving unit is driven by a return spring, the return spring is connected with the waist fixed support 2 and the waist connecting frame through joint bearings respectively, so as to make the waist connecting frame and the thigh connecting frame return to the initial relative position, and the exoskeleton device can realize rotation in the horizontal plane under the active driving of the wearer of the exoskeleton device. The return spring in the passive driving unit can adopt any one of a linear spring, a torsional spring and a pneumatic spring.

[0074] As a preferred embodiment of the present application, the hip joint sagittal plane driving unit is an active driving unit.

[0075] Specifically, referring to FIG. 1-3 and FIG. 6, the hip sagittal plane active driving unit is located on both sides of the device, each hip sagittal plane active driving unit is composed of two antagonistically arranged linear actuators, one side hip sagittal plane driving unit is driven by the third DC motor 4 and the fourth DC motor 12 cooperating with the threaded rod 18, the other side hip sagittal plane driving unit is driven by the fifth DC motor 8 and the sixth DC motor 15 cooperating with the threaded rod 18, the linear actuators connecting the waist connecting frame and the thigh connecting frame form a crank slider structure, the third DC motor 4, the fourth DC motor 12, the fifth DC motor 8 and the sixth DC motor 15 output dynamic rotation torque or holding torque through the threaded rod 18, for driving the hip joint of the lower extremity exoskeleton device to rotate smoothly in the sagittal plane, or keeping the hip joint standing in the sagittal plane, actively controlling the rotation angle, angular velocity and joint torque of the above-mentioned hip sagittal plane. For example, referring to FIG. 6, when the stroke patient wears the above-mentioned lower extremity exoskeleton device to walk, the third DC motor 4 rotates in the forward direction to provide a rotation torque, the fourth DC motor 12 rotates in the reverse direction to provide a reverse rotation torque, driving the lower extremity exoskeleton device to swing forward to a predetermined position in the sagittal plane on one side of the hip joint, the fifth DC motor 8 rotates in the forward direction to provide a rotation torque, the sixth DC motor 15 rotates in the reverse direction to provide a reverse rotation torque, driving the lower extremity exoskeleton device to swing backward to a predetermined position in the sagittal plane on the other side of the hip joint, the two sides of the hip joint alternately enter the swing phase and the support phase in the sagittal plane.

[0076] Specifically, referring to FIG. 4 and FIG. 5, the waist fixing support and the waist connecting frame are connected through a planar hinge.

[0077] As a preferred embodiment of the present application, the knee sagittal plane driving unit is an active driving unit or a semi-passive driving unit.

[0078] Specifically, referring to FIG. 2, FIG. 3, FIG. 7, FIG. 13 and FIG. 14, the knee sagittal plane driving unit is composed of antagonistically arranged linear driving units and magnetic control dampers, one side knee sagittal plane driving unit is composed of the seventh DC motor cooperating with threaded rod 18 transmission and the first magnetic control damper 13 driving, the other side knee sagittal plane driving unit is composed of the eighth DC motor cooperating with threaded rod 18 transmission and the second magnetic control damper 16 driving, the linear driver connects the thigh connecting frame and the shank connecting frame through the joint bearing to form a crank slider structure, the DC motor transmits the dynamic output holding torque or output torque through the threaded rod 18, which is used to keep the lower extremity exoskeleton device knee joint in the sagittal plane standing lock or smooth swing, actively controls the rotation angle, angular velocity and joint torque of the above-mentioned knee sagittal plane. For example, when the stroke patient wears the above-mentioned lower extremity exoskeleton device to walk, the seventh DC motor rotates in the positive direction to provide a rotating torque, which drives one side knee joint of the lower extremity exoskeleton device to swing in the sagittal plane to a predetermined position, the eighth DC motor rotates in the reverse direction to provide a reverse rotating torque, which drives the other side knee joint of the lower extremity exoskeleton device to swing in the sagittal plane to a predetermined position, so that the two sides of the shank structure alternately swing in phase and support phase.

[0079] Referring to FIG. 2 and FIG. 7, the first magnetic control damper 13, the second magnetic control damper 16 cooperate with the slide rod transmission to form a magnetic control damper driving unit, the magnetic control damper driving unit connects the thigh connecting frame and the shank connecting frame of the lower extremity exoskeleton device through the joint bearing to form a crank slider structure, the first magnetic control damper 13 driving unit and the seventh linear driver are arranged in opposition on one side, the second magnetic control damper 16 driving unit and the eighth linear driver are arranged in opposition on the other side, the magnetic control damper outputs static damping force or dynamic damping force, which is used to keep the lower extremity exoskeleton knee joint in the sagittal plane standing lock or smooth swing, by controlling the excitation current of the magnetic control damper, the rotation angle, angular velocity and joint torque of the hip joint in the sagittal plane are passively controlled.

[0080] Specifically, referring to FIG. 8, when the knee sagittal plane driving unit is a semi-passive driving unit, it is driven by a magnetic control damper cooperating with a return spring, the return spring can drive the knee joint to return to the initial position in the sagittal plane, the magnetic control damper forms a crank slider structure with the thigh connecting frame and the shank connecting frame, by controlling the excitation current of the magnetic control damper, the rotation angle, angular velocity and joint torque of the knee joint when bending and stretching in the sagittal plane can be passively controlled.

[0081] As a preferred embodiment of the present application, the ankle sagittal plane driving unit can adopt an active driving unit composed of one of a DC motor cooperating with a gear reducer and a harmonic reducer, which can actively control the rotation angle, angular velocity and output torque of the ankle joint in the sagittal plane.

[0082] Specifically, referring to FIG. 9, the active driving unit is composed of the ninth DC motor 7 or the tenth DC motor 10 cooperating with a gear reducer, the above-mentioned sagittal plane active driving unit of the ankle joint is fixed to the end of the lower extremity exoskeleton device calf support plate, and a dynamic output keeps torque and rotary torque for keeping the standing lock of the lower extremity exoskeleton ankle joint or for driving the sagittal plane rotation of the lower extremity exoskeleton device ankle joint, and the sagittal plane rotation angle, angular velocity and joint torque of the ankle joint are actively controlled.

[0083] As a preferred embodiment of the present application, referring to FIG. 10, the sagittal plane driving unit of the ankle joint can also be a semi-passive unit driven by a magnetic control damper cooperating with a return spring 23. The magnetic control damper includes a magnetorheological fluid valve 20, a magnetorheological fluid flow guide pipe 21 and a hydraulic cylinder 22. The return spring 23 drives the knee joint to return to the initial position in the sagittal plane extension, and the magnetic control damper forms a crank slider structure with the calf connecting frame and the instep fixed support, wherein the calf connecting frame is connected with the instep fixed support through a planar hinge, and by controlling the excitation current of the magnetic control damper, the rotation angle, angular velocity and joint torque of the ankle joint during bending and extension in the sagittal plane can be passively controlled.

[0084] As a preferred embodiment of the present application, referring to FIG. 11, the sagittal plane driving unit of the ankle joint can also be a passive driving unit, which includes two symmetrical return springs that can help the relative angle of the calf connecting frame and the instep fixed support to return to the initial position, and the calf connecting frame is connected with the instep fixed support through a planar hinge. The return spring in the passive driving unit is any one of a linear spring, a torsional spring and a pneumatic spring.

[0085] As a preferred embodiment of the present application, the inner surface of the lower extremity fixed support is integrated with a curved surface pressure measuring unit, which measures the contact stress between the lower extremity exoskeleton device and the wearer of the lower extremity exoskeleton device. The measured contact stress can be used to quantify the wearing comfort of the lower extremity fixed support, and can also be used to decode the motion intention of the wearer of the lower extremity exoskeleton.

[0086] Specifically, the sensors include lower extremity electromyography (EMG), joint angle sensors, pressure sensors distributed on the lower extremity fixed support, pressure measuring units distributed on the lower extremity fixed support, and inertial measurement units (IMU) installed on the instep, calf, thigh and waist of the lower extremity, etc.

[0087] Further, the lower extremity electromyography (EMG) is used to detect the electromyography of the muscles of the wearer of the lower extremity exoskeleton, thereby decoding the motion intention of the wearer, quantifying the rehabilitation effect of the wearer, and detecting the muscle movement fatigue of the lower extremity, etc.

[0088] The pressure measuring units distributed on the lower limb fixing support are used to detect the interaction force and moment between the above-mentioned exoskeleton and the wearer's limb, including the interaction force and moment between the fixing support and the user's thigh and calf, and the interaction force and moment between the user's plantar bottom and the foot bottom support plate of the lower limb exoskeleton; the inertial measurement unit is used to feedback the motion information of the lower limb exoskeleton device, including the motion direction, motion speed, motion acceleration, angle, angular velocity.

[0089] The controller identifies the motion intention of the user based on the signals obtained by the angle sensor, the pressure sensor and the electromyographic signal detection sensor, further controls the output torque of each direct current motor and damper of the lower limb exoskeleton device, controls the hip joint, knee joint and ankle joint of the lower limb exoskeleton device to rotate according to the set direction, angle, angular velocity and angular acceleration, so as to control the motion trajectory and motion posture of the hip joint, knee joint, ankle joint, thigh and calf structure of the lower limb exoskeleton device.

[0090] The pressure sensor is installed to the inner side of the fixing support and the foot bottom support plate, and is used to measure the interaction force between the user and the fixing support and the interaction force between the user and the ground.

[0091] Specifically, the foot bottom pressure sensor is fixed to the upper surface of the foot palm fixing support, and is used to feedback the interaction force between the foot bottom of the wearer and the foot palm fixing support of the lower limb exoskeleton device.

[0092] Specifically, the potentiometer is installed at the hip joint sagittal plane connection, the knee joint sagittal plane connection and the ankle joint sagittal plane connection, and is used to feedback the rotation angle of the hip joint, knee joint and ankle joint sagittal plane of the lower limb exoskeleton.

[0093] Specifically, the electromyographic signal detection sensor is installed on the inner surface of the thigh fixing support 3 and the calf fixing support 6, and through signal processing and calculation, the electrical signal generated by the main muscles of the lower limb is fed back to the control backpack in real time, and the muscle strength and fatigue degree information of the wearer is obtained through decoding. Referring to FIG. 12, in order to detect the interaction force between the thigh and calf of the wearer and the thigh fixing support 3 and the calf fixing support 6 of the lower limb exoskeleton device in real time, flexible pressure sensors 24 are fixed to the inner surfaces of the waist fixing support, the thigh fixing support 3 and the calf fixing support 6. Referring to FIG. 3, a force sensor 19 is fixed at the connection between the threaded screw rod 18 and the joint bearing, and is used to measure the axial force of the threaded screw rod 18 in the linear drive.

[0094] Specifically, referring to FIG. 12, the force sensitive area of the waist fixing support, the thigh fixing support 3, the calf fixing support 6 and the foot fixing support applies the negative Poisson's ratio intelligent structure unit 25, for improving the comfort of the wearer, while realizing firm fixing and reducing the contact stress concentration phenomenon. An inertial measurement unit is installed in the control backpack, for measuring the motion direction, motion speed, motion acceleration, angle and angular velocity of the feedback lower limb exoskeleton.

[0095] In summary, the lower limb dynamic exoskeleton device for rehabilitation assistance provided by the present application improves the lower limb exoskeleton fixing support, introduces the intelligent structure unit and the curved surface stress detection, improves the human-computer interaction performance of the exoskeleton device and the wearer, and is used for helping the lower limb movement function impaired patients, such as lower limb stroke patients, to realize walking rehabilitation training. FIG. 16 is a complete gait cycle motion state of the lower limb dynamic exoskeleton device for rehabilitation assistance provided by the present application, and FIGS. 17-19 show the change diagrams of the hip joint, knee joint and ankle joint sagittal plane angle, joint torque and joint power of the device when walking on the ground force plate. FIG. 20 is a ground force plate reaction force change diagram (a normal person walking on the ground force plate).

[0096] The above is only a preferred embodiment of the present application, and does not limit the present application in any form. Any simple modification, equivalent change and modification of the above embodiment according to the technical essence of the present application still belongs to the scope of the technical solution of the present application.

Claims

1. A lower extremity powered exoskeleton device for rehabilitation assistance, characterized by, It comprises: Ankle sagittal plane driving unit, which is one of active driving unit, semi-passive driving unit and passive driving unit, to realize ankle joint driving in sagittal plane; Knee sagittal plane driving unit, which is one of active driving unit and semi-passive driving unit, to realize knee joint driving in sagittal plane; Hip sagittal plane driving unit, which is active driving unit, to realize hip joint driving in sagittal plane; Hip horizontal plane driving unit, which is active driving unit or passive driving unit, to realize hip joint driving in horizontal plane; Joint driver connecting frame, which comprises waist connecting frame, thigh connecting frame and shank connecting frame, to connect and fix the ankle sagittal plane driving unit, knee sagittal plane driving unit, hip sagittal plane driving unit and hip horizontal plane driving unit; Lower limb fixing support, which comprises waist fixing support, thigh fixing support, shank fixing support and foot fixing support, to fix the waist, lower limb thigh, shank and foot plate of the wearer of the exoskeleton device with the exoskeleton device; Sensor, which is installed on the exoskeleton device and the wearer of the exoskeleton device, to detect the motion state of the exoskeleton and decode the motion intention of the wearer of the exoskeleton; Controller, to control the motion angle, angular velocity and output torque of the ankle sagittal plane driving unit, knee sagittal plane driving unit, hip sagittal plane driving unit and hip horizontal plane driving unit; Power supply, to supply power for the driving unit, sensor and controller of the exoskeleton device.

2. The lower limb powered exoskeleton device for rehabilitation assistance according to claim 1, wherein: The waist fixing support is fixed on the waist connecting frame, the thigh fixing support is fixed on the thigh connecting frame, the shank fixing support is fixed on the shank connecting frame, and the foot fixing support is connected with the shank connecting frame through the ankle sagittal plane driving unit.

3. The lower limb powered exoskeleton device for rehabilitation assistance according to claim 1, wherein: The waist connecting frame and the thigh connecting frame are connected through one of planar hinge connection and spherical surface connection, and the thigh connecting frame and the shank connecting frame are connected through planar hinge connection.

4. The lower limb powered exoskeleton device for rehabilitation assistance according to claim 1, wherein: The hip sagittal plane driving unit is driven by two antagonistically arranged linear drives, which contain DC motors, and the DC motors are matched with threaded lead screws to drive, while having displacement feedback and force feedback, and the linear drives form a crank slider structure with the waist connecting frame and the thigh connecting frame, so as to actively control the rotation angle, angular velocity and joint torque of the hip in sagittal plane.

5. The lower limb powered exoskeleton device for rehabilitation assistance according to claim 1, wherein: The hip joint horizontal plane driving unit is an active driving unit, which is driven by two antagonistically arranged linear drives containing DC motors cooperating with threaded rod transmission, while having displacement feedback and force feedback, and forms a crank slider structure with the waist connecting frame and the thigh connecting frame, so as to actively control the rotation angle, angular velocity and joint torque of the hip joint in the horizontal plane, realize turning motion, and the threaded rod transmission has a motor power-off self-locking function.

6. The lower limb powered exoskeleton device for rehabilitation assistance according to claim 1, wherein: The hip joint horizontal plane driving unit is a passive driving unit, which is driven by a return spring, so as to return the waist connecting frame and the thigh connecting frame to the initial relative position, and the exoskeleton device can realize rotation in the horizontal plane under the active driving of the exoskeleton device wearer.

7. The lower limb powered exoskeleton device for rehabilitation assistance according to claim 1, wherein: The knee joint sagittal plane driving unit is an active driving unit, which is driven by two antagonistically arranged linear drives containing DC motors cooperating with threaded rod transmission, while having displacement feedback and force feedback, and forms a crank slider structure with the thigh connecting frame and the shank connecting frame, so as to actively control the rotation angle, angular velocity and joint torque of the knee joint in the sagittal plane.

8. The lower limb powered exoskeleton device for rehabilitation assistance according to claim 1, wherein: The knee joint sagittal plane driving unit is an active driving unit, which is driven by an antagonistically arranged linear drive unit and a magnetic control damper, the linear drive contains a DC motor cooperating with threaded rod transmission, while having displacement feedback and force feedback, and forms a crank slider structure with the thigh connecting frame and the shank connecting frame, so as to actively control the rotation angle, angular velocity and joint torque of the knee joint in the sagittal plane, and the magnetic control damper forms a crank slider structure with the thigh connecting frame and the shank connecting frame, and by controlling the excitation current of the magnetic control damper, the rotation angle, angular velocity and joint torque of the knee joint in the sagittal plane can be passively controlled.

9. The lower limb powered exoskeleton device for rehabilitation assistance according to claim 1, wherein: The knee joint sagittal plane driving unit is a semi-passive driving unit, which is driven by a magnetic control damper cooperating with a return spring, the return spring can drive the knee joint to return to the initial position in the sagittal plane, the magnetic control damper forms a crank slider structure with the thigh connecting frame and the shank connecting frame, and by controlling the excitation current of the magnetic control damper, the rotation angle, angular velocity and joint torque of the knee joint in the sagittal plane can be passively controlled.

10. The lower limb powered exoskeleton device for rehabilitation assistance according to claim 1, wherein: The sagittal plane driving unit of the ankle joint is an active driving unit, which is composed of one of a DC motor, a gear reducer and a harmonic reducer, and can actively control the rotation angle, angular velocity and output torque of the ankle joint in the sagittal plane.

11. The lower limb powered exoskeleton device for rehabilitation assistance according to claim 1, characterized in that: The sagittal plane driving unit of the ankle joint is a semi-passive unit, which is driven by a magnetic control damper cooperating with a return spring, the return spring can drive the knee joint to return to the initial position in the sagittal plane, and the magnetic control damper and the calf connecting frame and the instep fixed support form a crank slider structure, wherein the calf connecting frame and the instep fixed support are connected through a planar hinge, and by controlling the exciting current of the magnetic control damper, the rotation angle, angular velocity and joint torque of the ankle joint during flexion and extension in the sagittal plane can be passively controlled.

12. The lower limb powered exoskeleton device for rehabilitation assistance according to claim 1, characterized in that: The sagittal plane driving unit of the ankle joint is a passive driving unit, which is composed of a return spring, which can help the relative angle of the calf connecting frame and the instep fixed support to return to the initial position, and the calf connecting frame and the instep fixed support are connected through a planar hinge.

13. The lower limb powered exoskeleton device for rehabilitation assistance according to claim 1, characterized in that: The lower limb fixed support is used to fix the lower limb exoskeleton device and the wearer of the lower limb exoskeleton device, and the lower limb fixed support is provided with a negative Poisson's ratio intelligent structure unit in the partial force bearing area.

14. The lower limb powered exoskeleton device for rehabilitation assistance according to claim 1, characterized in that: The inner surface of the lower limb fixed support is integrated with a curved surface pressure measuring unit, which measures the contact stress between the lower limb exoskeleton device and the wearer of the lower limb exoskeleton device, and the measured contact stress can be used to quantify the wearing comfort of the lower limb fixed support, and can also be used to decode the motion intention of the wearer of the lower limb exoskeleton.

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