A wearable knee exoskeleton mechanism

Abstract

The wearable knee exoskeleton mechanism comprises a leg wearing module, a continuum structure and a driving device. The leg wearing module comprises a thigh wearing module and a shank wearing module. The continuum structure comprises a plurality of link units connected in series. Adjacent two link units can rotate relative to each other within a set angle range. The first end of the continuum structure is connected with the thigh wearing module, and the second end is connected with the shank wearing module. The continuum structure can provide an auxiliary torque for the knee joint in the squatting and standing process under the action of the driving device, so as to assist the user to complete the squatting and standing action.

Description

Technical Field

[0001] This article relates to wearable knee exoskeleton technology, and more particularly to a wearable knee exoskeleton mechanism. Background Technology

[0002] Exoskeletons are mechanical devices designed to assist users in limb movements, providing aids to reduce the burden of exercise. They have broad application prospects in fields such as elderly and disabled care, rehabilitation medicine, and human enhancement. Currently, exoskeleton research is mainly applied to upper limb rehabilitation training and gait assistance for lower limbs during walking.

[0003] Traditional rigid exoskeletons typically use rigid structures such as rods to mimic the human skeleton for support and weight-bearing. At the joints, they employ structures such as series elastic actuators (SEA), parallel elastic actuators (PEA), and variable stiffness actuators (VSA) to drive the relative rotation of the torso at both ends of the joint and provide the user with the necessary auxiliary torque for movement. These structures possess compliant control characteristics, exhibiting a degree of compliance through elastic deformation during control, preventing user injury. Furthermore, these actuators generate joint torque that directly drives the joint, providing uniform torque output throughout the joint's range of motion. However, these actuators often struggle to ensure perfect alignment between their rotation axis and the human joint's rotation axis. Additionally, research indicates that the knee joint exhibits sliding during rotation, constituting non-fixed-axis rotation. Therefore, these exoskeleton devices often suffer from misalignment between the structural rotation axis and the human joint's rotation axis, resulting in parasitic forces at the joint, which can affect user comfort and even lead to injury.

[0004] Considering that ropes are flexible structures that can bend and deform, and have the advantages of being lightweight and inexpensive, rope-driven systems have been widely used in various exoskeleton devices in recent years. Existing devices can be broadly divided into two categories: one is where the drive motor is directly located at the knee joint pivot. This type of device requires the drive motor and gearbox to be placed at the knee joint, resulting in a heavier structure and less flexibility for the user when moving their lower limbs; the other type is a rope-driven device, but because it usually does not have an added structure for lever arm amplification, the auxiliary torque it provides is usually small and difficult to meet the torque requirements for squatting to standing movements. Summary of the Invention

[0005] This application provides a wearable knee exoskeleton mechanism that can provide auxiliary torque to the human knee joint, thereby assisting the human body in completing the squatting and standing motion.

[0006] This application provides a wearable knee exoskeleton mechanism, comprising:

[0007] Leg wearable modules, including thigh wearable modules and calf wearable modules;

[0008] The continuous structure includes multiple chain link units connected in series. Each adjacent chain link unit can rotate relative to the other within a set angle range. The first end of the continuous structure is connected to the thigh wearing module, and the second end is connected to the calf wearing module. This allows the continuous structure to provide an auxiliary torque to the knee joint during the squatting and standing process under the force of the driving device, so as to assist the user in completing the squatting and standing action.

[0009] In one exemplary embodiment, the rotation axis of the link unit is perpendicular to the unfolding plane of the wearable knee exoskeleton mechanism under stress.

[0010] In an exemplary embodiment, the first end of the continuum structure is configured to be connected to the driving device, and the continuum structure is configured to switch between a flexible state and a rigid state;

[0011] Since the leg-wearing module is in an upright state and the continuous structure is in a flexible state, any two connected link units can rotate within the set angle range;

[0012] Since the leg-wearing module is in a squatting state, the continuous structure reaches the limit of the angle range and is in a rigid state under the pulling force of the driving device, so that any two adjacent chain link units remain relatively stationary.

[0013] In an exemplary embodiment, each of the link units has a movable connecting portion at both ends along the elongation direction of the continuum structure, and the movable connecting portions of adjacent link units are rotatably connected.

[0014] Any two adjacent link units are further provided with mutually cooperating limiting parts to limit the rotation angle of the two adjacent link units within the set angle range.

[0015] In one exemplary embodiment, the limiting portions of adjacent link units are configured to be connected by flexible limiting members to limit the relative rotation angle range of adjacent link units.

[0016] In one exemplary embodiment, the limiting part includes a pull ring or pull rod disposed at one end of the link unit opposite to the leg wearing module, and the flexible limiting member is a rope.

[0017] In an exemplary embodiment, the movable connection portion of the link unit is provided with a mounting hole, a bushing is provided in the mounting hole and a gasket is provided on the outside of the opening of the mounting hole, adjacent link units are connected by a rotating shaft passing through the mounting hole, and the bushing and the gasket respectively prevent the rotating shaft from contacting the link unit.

[0018] In an exemplary embodiment, the first end of the continuum structure is provided with a tie unit, one end of which can be connected to the pull rope of the drive device, and the other end is rotatably connected to the adjacent link unit; the rotation axis of the tie unit is parallel to the rotation axis of the adjacent link unit.

[0019] In an exemplary embodiment, the thigh-wearing module includes one or more spaced-apart first fixing rings, a guide seat disposed on the first fixing ring, and a guide portion mounted on the guide seat and rotatable relative to the guide seat, wherein the guide portion is through which the pull cord of the drive device passes and is connected to the first end.

[0020] In one exemplary embodiment, the calf wearing module includes one or more spaced second fixing rings and a fixing seat disposed on the second fixing rings, wherein the second end of the continuous structure is fixedly connected to or rotatably connected to the fixing seat.

[0021] In one exemplary embodiment, both the first fixing ring and the second fixing ring include an arc-shaped frame and a strap that engages with the arc-shaped frame and has an adjustable length.

[0022] In one exemplary embodiment, the knee exoskeleton mechanism further includes a drive device connected to the continuum structure. The drive device includes a drive motor, a roller cooperating with the drive motor, and a pull rope wound around the roller. The pull rope is connected to a first end of the continuum structure. The drive motor is configured to drive the roller to rotate and retract the pull rope to apply tension to the continuum structure, thereby providing an auxiliary torque applied by the continuum structure to the knee joint.

[0023] In one exemplary embodiment, the knee exoskeleton mechanism further includes a tension sensor, one end of which is connected to a first end of the continuum structure and the other end of which is connected to the pull rope. The tension sensor detects the tension exerted by the pull rope on the continuum structure and feeds it back to the drive device. The drive device controls the magnitude of the tension exerted on the continuum structure based on the tension information fed back by the tension sensor.

[0024] In one exemplary embodiment, the auxiliary torque is based on the equivalent cable node coordinates of the continuum structure. and equivalent rotation coordinates and the coordinates of the rope exit point on the rope guide. Sure;

[0025] The equivalent cable node coordinates The following method is used to determine:

[0026] Step 1: Take ;

[0027] Step 2: Locate the rope point coordinates on the rope guide section using the pull rope. The coordinates of the end rotation axis of the preceding link unit The predicted rope direction is obtained. ;

[0028] Step 3: Based on the obtained estimated rope direction and before Relative rotation angle of link link unit Determine the first The estimated deflection angle of a link segment relative to the preceding link segment ;

[0029] Step 4: The obtained predicted deflection angle and the set rotation angle limit value Determine the first The actual deflection angle of a link unit relative to the previous link unit And determine the coordinates of the rotation axis at the end of the next link unit. ,like ,but And take the equivalent cable node of the continuum structure as And end the calculation;

[0030] Step 5, otherwise if Then take And determine the coordinates of the rotation axis at the end of the next link unit. ;

[0031] Step Six: Take ;like The equivalent cable node of the continuum structure is taken as If the calculation ends, proceed to step two through six.

[0032] in, Indicates the sequence number of the link unit; Indicates the number of all link units; Indicates the first The intersection of the starting axis of each link unit and the unfolded plane The coordinates; Indicates the first The intersection of the terminal pivot of each link unit and the unfolded plane coordinate; This indicates the distance between the starting and ending shafts; Point and points The distance between them; Indicates the first The link unit and the first The angle between each link unit.

[0033] Compared with related technologies, the wearable knee exoskeleton mechanism of this application embodiment can provide an auxiliary torque to the human knee joint when the human body squats and stands up, thereby assisting the human body to complete the squatting and standing up action. Under the condition that the driving device provides a certain force, it can maximize the auxiliary torque generated by the structure at the knee joint. It also has good flexibility, is easy for the human body to wear, and prevents inconvenience or injury to the body's movement.

[0034] Other features and advantages of this application will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the application. Other advantages of this application can be realized and obtained by means of the solutions described in the description and the accompanying drawings. Attached Figure Description

[0035] The accompanying drawings are used to provide an understanding of the technical solutions of this application and constitute a part of the specification. They are used together with the embodiments of this application to explain the technical solutions of this application and do not constitute a limitation on the technical solutions of this application.

[0036] Figure 1 This is an overall view of the wearable knee exoskeleton mechanism according to an embodiment of this application worn on a human leg;

[0037] Figure 2 This is a side view of the wearable knee exoskeleton mechanism of this application worn on the human leg when the person is standing.

[0038] Figure 3 This is a side view of the wearable knee exoskeleton mechanism of this application worn on the human leg when the human body is squatting.

[0039] Figure 4 for Figure 3 Side view;

[0040] Figure 5 This is a partial enlarged view of the continuum structure of the wearable knee exoskeleton mechanism according to an embodiment of this application;

[0041] Figure 6 This is a perspective view of the link unit of the continuum structure of the wearable knee exoskeleton mechanism according to an embodiment of this application;

[0042] Figure 7 This is an enlarged view of the upper part of the wearable knee exoskeleton mechanism according to an embodiment of this application.

[0043] Figure 8 This is an enlarged view of the lower half of the wearable knee exoskeleton mechanism according to an embodiment of this application;

[0044] Figure 9 This is a perspective view of the drive device of the wearable knee exoskeleton mechanism according to an embodiment of this application;

[0045] Figure 10 This is a schematic diagram of the geometric parameters of the wearable knee exoskeleton mechanism according to an embodiment of this application. Detailed Implementation

[0046] This application describes several embodiments, but these descriptions are exemplary and not limiting, and it will be apparent to those skilled in the art that many more embodiments and implementations are possible within the scope of the embodiments described herein. Although many possible combinations of features are shown in the drawings and discussed in the detailed description, many other combinations of the disclosed features are also possible. Unless specifically limited, any feature or element of any embodiment may be used in combination with or in lieu of any other feature or element in any other embodiment.

[0047] This application includes and contemplates combinations of features and elements known to those skilled in the art. The embodiments, features, and elements disclosed in this application may also be combined with any conventional features or elements to form a unique inventive scheme as defined by the claims. Any feature or element of any embodiment may also be combined with features or elements from other inventive schemes to form another unique inventive scheme as defined by the claims. Therefore, it should be understood that any feature shown and / or discussed in this application may be implemented individually or in any suitable combination. Therefore, the embodiments are not limited except by the limitations imposed by the appended claims and their equivalents. Furthermore, various modifications and changes may be made within the scope of the appended claims.

[0048] Furthermore, in describing representative embodiments, the specification may have presented methods and / or processes as a specific sequence of steps. However, the method or process should not be limited to the specific order of steps described herein, to the extent that it does not depend on such a specific order. As will be understood by those skilled in the art, other sequences of steps are also possible. Therefore, the specific order of steps set forth in the specification should not be construed as a limitation of the claims. Moreover, the claims concerning the method and / or process should not be limited to the steps performed in the written order, and those skilled in the art will readily understand that these orders can be varied and still remain within the spirit and scope of the embodiments of this application.

[0049] like Figures 1-10 As shown, this application embodiment provides a wearable knee exoskeleton mechanism 100, including a leg wearing module 1 and a continuous structure 2. The leg wearing module 1 includes a thigh wearing module 11 and a lower leg wearing module 12. The thigh wearing module 11 is worn on the thigh of the human body, and the lower leg wearing module 12 is worn on the lower leg of the human body. The continuous structure 2 includes a plurality of chain link units 20 connected in series. Any two adjacent chain link units 20 can rotate relative to each other within a set angle range. The first end of the continuous structure 2 is connected to the thigh wearing module 11, and the second end is connected to the lower leg wearing module 12, so that the continuous structure 2 can provide an auxiliary torque for the knee joint during the squatting and standing process under the action of the driving device 3, so as to assist the user in completing the squatting and standing action.

[0050] The wearable knee exoskeleton mechanism 100 of this application embodiment can provide an auxiliary torque to the human knee joint when the human body squats and stands up, thereby assisting the human body to complete the squatting and standing up action. Under the condition that the driving device provides a certain force, it can maximize the auxiliary torque generated by the structure at the knee joint. It also has good flexibility, is easy for the human body to wear, and prevents inconvenience or injury to the body's movement.

[0051] like Figure 2 , Figure 4 As shown, in this embodiment, the rotation axis of the link unit 20 is perpendicular to the unfolding plane of the wearable knee exoskeleton mechanism 100 in a stressed state (the shape when the human body is squatting). Therefore, the rotation direction of the link unit 20 corresponds to the bending direction of the human leg, and it can straighten or bend following changes in the direction of the pulling force of the rope. The unfolding plane is almost parallel to the sagittal plane of the human body, and the rotation axis of the human knee joint is perpendicular to the unfolding plane. Figures 1-4As shown, the first end of the continuum structure 2 is connected to the driving device 3. The continuum structure 2 is configured to switch between a flexible state (no force applied when the human body is not squatting) and a rigid state (force applied when the human body is squatting). Since the leg-wearing module 1 is in an upright state and the continuum structure 2 is in a flexible state, any two connected link units 20 can rotate within a set angle range (see figure). Figure 2 As shown); with the leg-wearing module 1 in a squatting state, the continuous structure 2, under the pulling force of the driving device 3, reaches the rotation range limit and is in a rigid state, so that any two adjacent chain link units 20 remain relatively stationary (see...). Figure 3 (As shown).

[0052] like Figure 5 , Figure 6 As shown, each end of the link unit 20 along the elongation direction of the continuous structure 2 is provided with a movable connecting part 201, and the movable connecting parts of adjacent link units 20 are rotatably connected. Any two adjacent link units 20 are also provided with mutually cooperating limiting parts 202 to limit the rotation angle of the two adjacent link units 20 within a set angle range.

[0053] In this embodiment, the limiting portion 202 of adjacent link units 20 is configured to be connected by a flexible limiting member to limit the relative rotation angle range of adjacent link units 20. For example, the limiting portion 202 includes a pull ring or pull rod provided at one end of the link unit 20 away from the leg wearing module 1, and the flexible limiting member is a rope.

[0054] The continuous structure 2 of this application embodiment can limit the rotation angle of two adjacent chain link units 20 by setting the limiting part 202, and by reasonably adjusting the knot length of the rope, the maximum relative rotation angle of two adjacent chain link units 20 can be limited to a specific value as desired.

[0055] like Figure 5 , Figure 6 As shown, the movable connecting portion 201 of adjacent link units 20 can be rotatably connected by a rotating shaft A, which can be a pin. A mounting hole is provided on the movable connecting portion 201 at the end of the link unit 20, and a bushing 20a is installed in the mounting hole. A gasket 20b is installed on the outside of the mounting hole. Adjacent link units 20 are connected by a rotating shaft A passing through the mounting hole. The bushing 20a and gasket 20b respectively prevent the rotating shaft A from contacting the link unit 20. Both the bushing 20a and the gasket 20b are made of polytetrafluoroethylene (PTFE).

[0056] The outer ring of the bushing 20a mates with the upper mounting hole of the link unit 20. Pin A passes through the central hole of the PTFE bushing 20a and coaxially engages with the inner rings of the PTFE bushing 20a and the PTFE washer 20b. Pin A also passes through two coaxial holes on the lower side of adjacent link units 20, making pin A the pivot of the two adjacent link units 20, allowing them to rotate relatively freely within a certain range. The PTFE bushing 20a and the PTFE washer 20b are used to isolate pin A from the link unit 20, reducing friction between them and making the rotation between adjacent link units 20 of the continuous structure 2 smoother. The side of pin A away from the pin head has threads, which are used to axially lock adjacent link units 20 together using fasteners such as round nuts B.

[0057] like Figure 7 As shown, the first end of the continuum structure 2 is provided with a tie unit 21. One end of the tie unit 21 can be connected to the pull rope 30 of the drive device 3, and the other end is rotatably connected to the adjacent link unit 20. The rotation axis of the tie unit 21 is parallel to the rotation axis of the adjacent link unit 20.

[0058] like Figure 7 As shown, the thigh-wearing module 11 includes one or more spaced-apart first fixing rings 110, a guide seat 111 disposed on the first fixing ring 110, and a guide portion 112 mounted on the guide seat 111 and rotatable relative to the guide seat 111. The guide portion 112 allows the pull cord 30 of the drive device 3 to pass through and connect to the first end of the continuous structure 2. The guide portion 112 can adapt to the direction of the pull cord 30 during the user's squatting and standing movements.

[0059] The first fixing ring 110 includes an arc-shaped frame 110a and a strap 110b that engages with the arc-shaped frame 110a and is adjustable in length. Dividing the first fixing ring 110 into a front part (arc-shaped frame 110a) and a rear part (strap 110b) increases the strength of the connection with the chain link unit 20 and facilitates locking to the user's leg. The guide portion 112 is fixed to the guide seat 111, which is connected to the first fixing ring 110, by a pin C.

[0060] The device includes a buckle 1101 on the strap 110b and an insertion port on the arc-shaped frame 110a (not shown in the attached diagram due to the connection state). The buckle 1101 can be inserted into the insertion port, allowing for easy removal and insertion for user comfort. The buckle 1101 also has a buckle 1102 fixed to it, through which the strap 110b passes and wraps around itself, securing the strap 110b and allowing users to adjust the length of the thigh-mounted strap according to their body shape. When using the device, the thigh module 11 secures it to the user's thigh.

[0061] like Figure 8 As shown, the lower leg wearing module 12 includes one or more spaced-apart second fixing rings 120 and a fixing seat 121 disposed on the second fixing ring 120. The second end of the continuous structure 2 is fixedly connected to or rotatably connected to the fixing seat 121. Similarly, the second fixing ring 120 includes an arc-shaped frame 120a and a strap 120b that engages with the arc-shaped frame 120a and is adjustable in length. The strap 120b is provided with a buckle 1201, and the arc-shaped frame 120a is provided with an insertion port that engages with the buckle. Similarly, dividing the second fixing ring 121 into a front part of the arc-shaped frame 120a and a rear part of the strap 120b can increase the strength of the connection and facilitate locking with the human leg. For details, please refer to the thigh wearing module 11, which will not be described in detail here.

[0062] like Figure 1 , Figure 9 As shown, the knee exoskeleton mechanism 100 of this embodiment further includes a drive device 3 connecting the continuous structure 2, comprising a mounting frame 301, two sets of drive units 302 mounted on the mounting frame 301, two sets of motor mounting plates 303, and rollers 31 respectively mounted on the output shafts of the two sets of drive units. Each drive unit 302 includes a DC motor 3020 and a reducer 3021, and is mounted on the motor mounting plate 303. The DC motor 3020 has one output shaft, and the reducer 3021 has one output shaft and one input shaft. The output shaft of the DC motor 3020 is connected to the input shaft of the reducer 3021. The reducer 3021 achieves the speed ratio between the input and output shafts through an internal gear system. The output shaft of the reducer 3021 is connected to the rollers 31. The two sets of drive units 302 drive the two rollers 31 to independently drive the two pull ropes 30, thereby simultaneously assisting the user's legs.

[0063] The first end of the pull rope 30 is connected to the continuous structure, and the second end is fixedly connected to the roller 31 and wound around the roller 31. The pull rope 30 is specifically fixed to the roller 31 by using screw holes on the end face of the roller 31 to tighten the end of the pull rope 30 with set screws. The pull rope 30 can be made of Bowden wire.

[0064] The drive unit 302 is configured to drive the roller 31 to rotate and retract the pull rope 30 to apply tension to the continuous structure 2, providing an auxiliary torque to the continuous structure 2. Specifically, the DC motor 3020 drives the roller 31 to retract the pull rope 30 via the reducer 3021, and then the pull rope 30 applies an auxiliary torque to the knee joint through the continuous structure 2, thereby providing assistance to the user's leg and knee joint.

[0065] like Figure 7As shown, the knee exoskeleton mechanism 100 of this embodiment further includes a tension sensor 4. One end of the tension sensor 4 is connected to the first end of the continuous structure 2, and the other end is connected to the pull rope 30. The sensor detects the tension applied to the continuous structure 2 by the pull rope 30 and feeds it back to the drive device 3. The drive device 3 accurately controls the actual tension applied to the continuous structure 2 based on the tension information fed back by the tension sensor 4. The tension sensor 4 can achieve accurate control of the rope tension through closed-loop feedback.

[0066] The drive device 3 can provide appropriate tension to the continuous structure 2 during the squatting and standing process of the human body, and increase the lever arm. The drive device 3 can also retract the pull rope during the standing process of the human body.

[0067] like Figure 10 As shown, the auxiliary torque provided by the wearable knee exoskeleton mechanism 100 in this embodiment can be determined in the following manner:

[0068] The knee joint auxiliary torque provided by the continuum structure 2 is related to the length of the link unit 20. and the maximum rotation angle between every two adjacent units And the coordinates of the rope exit point of the pull rope 30 on the rope guide. The magnitude of the auxiliary torque it can generate is approximately equal to the product of the tension of the rope 30 and the equivalent force arm of the continuum structure 2 relative to the knee joint.

[0069] To determine structural parameters and To facilitate design guidance and to influence the auxiliary torque, the following provides a method for estimating the equivalent force arm and auxiliary torque of the continuum structure 2 relative to the knee joint. The equivalent force arm of the continuum structure 2 relative to the user's knee joint rotation axis can be estimated using the user's posture and the parameters of the continuum structure 2. and the auxiliary torque provided to the knee joint The estimation method is as follows:

[0070] The origin is the intersection of the starting axis of the link unit 20 of the continuous structure 2 on the fixed base 121 connected to the continuous structure 2 and the unfolded plane. O The direction from the center of the starting shaft of the link unit 20, which is connected to the fixed base 121 by the continuous structure 2, to the direction of the ending shaft is... y Establish a coordinate system in the unfolded plane along the positive axis. Let the continuum structure be defined by... It consists of one link unit 20 and one ligature unit 21; denoted as the first... The intersection of the initial rotation axis of each continuous structural link unit 20 and the unfolded plane is: Its coordinates are The intersection of the terminal pivot and the unfolded plane is Let its coordinates be... The distance between its starting and ending shafts for ; Record the first The first continuous structural link unit and the first The included angle between the continuous structural link units is The included angle satisfies the range The point at which the pull rope 30 exits the rope on the rope guide 112 is recorded as follows: Let its coordinates be... .

[0071] Considering this problem within the unfolded plane, we simplify it into a geometric problem within the plane. Since the equivalent cable node of continuum structure 2 is the coordinate of the initial rotation axis of the first free link element in the structure, which is also the coordinate of the final rotation axis of the last link element reaching its limit, the coordinates of the equivalent cable node of the continuum structure can be calculated using the following iterative method. :

[0072] First, starting from the beginning of the link unit 20 near the lower leg, calculate the coordinates of the pivot point at the end of each link unit 20. That is, calculate the coordinates of the rope exit point on the guide section 112 of the rope 30. The coordinates of the end rotation axis of the preceding link unit 20 Calculate the coordinates of the rotation axis at the end of the next link unit. The calculation is performed iteratively according to the following algorithm.

[0073] (1) Take ;

[0074] (2) (The coordinates of the rope exit point on the rope guide 112 by the pull rope 30) The coordinates of the end rotation axis of the preceding link unit Calculate and estimate rope direction )calculate ;where Δ x ,Δ y ,Δ z Represents the direction vector corresponding to the rope. x Directional components, y Directional components and z Directional component.

[0075] (3) Based on the estimated rope direction calculated in the previous step and before Relative rotation angle of link links Calculate the first The estimated deflection angle of a link segment relative to the preceding link segment Calculation formula: ; Indicates the first j The first continuous structural link unit and the first j -1 is the angle between the chain segments of a continuum structure.

[0076] (4) According to the first The estimated deflection angle of a link segment relative to the preceding link segment and the set rotation angle limit value Calculate the first The actual deflection angle of a link unit relative to the previous link unit ;like Then take And calculate the coordinates of the rotation axis at the end of the next link unit. Calculation formula: And take the equivalent cable node of the continuum structure as And end the calculation;

[0077] (5) Otherwise if Then take At the same time ;in j The subscript for the summation operation is used during the calculation process. j It will be eliminated and will not be present in the final calculation result. j .

[0078] (6) Take ;like The equivalent cable node of the continuum structure is taken as If the calculation ends, then repeat steps (2) to (6).

[0079] Let the equivalent rotation axis coordinate of the knee joint be... Based on the above calculations, the equivalent cable point coordinates of the continuum structure are obtained. The corresponding equivalent force arm is calculated to be ,in , nz The unit normal vector corresponding to the unfolded plane is used to describe the direction, and its direction is approximately parallel to the line containing the knee joint rotation axis. Furthermore, this can be determined based on the equivalent force arm. and the tension of the rope on the pull rope 30 The auxiliary torque on the knee joint was calculated. ,for .

[0080] Based on the above derivation, it can be determined that the wearable knee exoskeleton mechanism 100 of this application embodiment has a large equivalent force arm when the user squats, thus providing a large knee joint assist torque. Furthermore, the above formula can guide dimensional design.

[0081] The wearable knee exoskeleton mechanism 100 of this application embodiment is characterized by gradually increasing the equivalent force arm of the pull rope relative to the knee joint during the squatting process, thereby increasing the auxiliary torque on the knee joint.

[0082] The wearable knee exoskeleton mechanism 100 of this application embodiment increases the equivalent arm of the pull rope relative to the knee joint pivot when the user squats, thus enabling the mechanism to provide a larger auxiliary torque to the knee joint. The wearable knee exoskeleton mechanism 100 has a simple and lightweight structure, and its equivalent arm relative to the knee joint is large when the user is in a deep squatting position.

[0083] In the description of this application, it should be noted that the terms "upper", "lower", "one side", "the other side", "one end", "the other end", "side", "opposite", "four corners", "periphery", "square structure", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the structure referred to has a specific orientation, or is constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0084] In the description of the embodiments of this application, unless otherwise expressly specified and limited, the terms "connection," "direct connection," "indirect connection," "fixed connection," "installation," and "assembly" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection. The terms "installation," "connection," and "fixed connection" can refer to a direct connection or an indirect connection through an intermediate medium, or they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0085] Although the embodiments disclosed in this application are as described above, the content described is merely for the purpose of understanding this application and is not intended to limit this application. Any person skilled in the art to which this application pertains may make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed in this application, but the scope of patent protection of this application shall still be defined by the appended claims.

Claims

1. A wearable knee exoskeleton mechanism, characterized in that, include: Leg wearable modules, including thigh wearable modules and calf wearable modules; The continuous structure includes multiple chain link units connected in series. Each adjacent chain link unit can rotate relative to the other within a set angle range. The first end of the continuous structure is connected to the thigh wearing module, and the second end is connected to the calf wearing module. This allows the continuous structure to provide an auxiliary torque to the knee joint during the squatting and standing process under the force of the driving device, so as to assist the user in completing the squatting and standing action. The first end is configured to be connected to the driving device, and the continuum structure is configured to switch between a flexible state and a rigid state. When the leg-wearing module is in an upright position, the continuous structure is in a flexible state, and any two connected link units can rotate within the set angle range; when the leg-wearing module is in a squatting state, the continuous structure reaches the limit of the angle range and is in a rigid state under the pulling force of the driving device, so that any two adjacent link units remain relatively stationary. Each link unit has a movable connecting portion at both ends along the elongation direction of the continuous structure, and the movable connecting portions of adjacent link units are rotatably connected; any two adjacent link units are also provided with mutually cooperating limiting portions to limit the rotation angle of the two adjacent link units within the set angle range; the limiting portions of adjacent link units are configured to be connected by flexible limiting members to limit the relative rotation angle range of adjacent link units.

2. The knee joint exoskeleton mechanism according to claim 1, characterized in that, The rotation axis of the link unit is perpendicular to the unfolding plane of the wearable knee exoskeleton mechanism under stress.

3. The knee joint exoskeleton mechanism according to claim 1, characterized in that, The limiting part includes a pull ring or pull rod located at one end of the chain link unit opposite to the leg wearing module, and the flexible limiting member is a rope.

4. The knee joint exoskeleton mechanism according to claim 1, characterized in that, The movable connection part of the chain link unit is provided with a mounting hole, a bushing is provided in the mounting hole and a gasket is provided on the outside of the opening of the mounting hole. Adjacent chain link units are connected by a rotating shaft passing through the mounting hole. The bushing and the gasket respectively prevent the rotating shaft from contacting the chain link unit.

5. The knee joint exoskeleton mechanism according to claim 1, characterized in that, The first end of the continuum structure is provided with a tie unit. One end of the tie unit can be connected to the pull rope of the drive device, and the other end is rotatably connected to the adjacent link unit. The rotation axis of the tie unit is parallel to the rotation axis of the adjacent link unit.

6. The knee joint exoskeleton mechanism according to claim 5, characterized in that, The thigh-wearing module includes one or more spaced-apart first fixing rings, a guide seat disposed on the first fixing ring, and a guide portion mounted on the guide seat and rotatable relative to the guide seat. The guide portion allows the pull cord of the drive device to pass through and connect to the first end of the continuous structure.

7. The knee joint exoskeleton mechanism according to claim 6, characterized in that, The calf wearing module includes one or more spaced second fixing rings and a fixing seat disposed on the second fixing rings. The second end of the continuous structure is fixedly connected to or rotatably connected to the fixing seat.

8. The knee joint exoskeleton mechanism according to claim 7, characterized in that, Both the first fixing ring and the second fixing ring include an arc-shaped frame and a strap that engages with the arc-shaped frame and has an adjustable length.

9. The knee joint exoskeleton mechanism according to any one of claims 6-8, characterized in that, It also includes a drive device for connecting the continuous structure. The drive device includes a drive motor, a roller that is installed in conjunction with the drive motor, and a pull rope wound around the roller. The pull rope is connected to a first end of the continuous structure. The drive motor is configured to drive the roller to rotate and retract the pull rope to apply tension to the continuous structure and provide an auxiliary torque applied by the continuous structure to the knee joint.

10. The knee joint exoskeleton mechanism according to claim 9, characterized in that, It also includes a tension sensor, one end of which is connected to the first end of the continuous structure and the other end is connected to the pull rope. The tension sensor detects the tension of the pull rope on the continuous structure and feeds it back to the driving device. The driving device controls the magnitude of the tension on the continuous structure based on the tension information fed back by the tension sensor.

11. The knee exoskeleton mechanism according to claim 9, characterized in that, The auxiliary torque is based on the equivalent cable node coordinates of the continuum structure. And equivalent rotation coordinates are and the coordinates of the rope exit point on the guide section. Sure; The equivalent cable node coordinates The following method is used to determine: Step 1: Take ; Step 2: Locate the rope point coordinates on the guide section using the pull rope. The coordinates of the end rotation axis of the preceding link unit This yields the predicted rope direction; Step 3: Based on the obtained estimated rope direction and forward... Relative rotation angle of link link unit Determine the first The estimated deflection angle of a link segment relative to the preceding link segment ; Step 4: The obtained predicted deflection angle and the set rotation angle limit value Determine the first The actual deflection angle of a link unit relative to the previous link unit And determine the coordinates of the rotation axis at the end of the next link unit. ,like ,but And take the equivalent cable node of the continuum structure as And end the calculation; Step 5, otherwise if Then take ,but ; Step Six: Take ;like The equivalent cable node of the continuum structure is taken as If the calculation ends, proceed to step two through six. in, Indicates the sequence number of the link unit; Indicates the number of all link units; Indicates the first The intersection of the starting axis of each link unit and the unfolded plane The coordinates; Indicates the first The intersection of the terminal pivot of each link unit and the unfolded plane coordinate; This indicates the distance between the starting and ending shafts; Point and points The distance between them; Indicates the first The link unit and the first The included angle between each link unit; Let the equivalent rotation axis coordinate of the knee joint be... Based on the above calculations, the equivalent cable point coordinates of the continuum structure are obtained. The corresponding equivalent force arm is calculated to be ,in , nz The unit normal vector corresponding to the unfolded plane is used to describe the direction, and its direction is approximately parallel to the line containing the knee joint rotation axis; according to the equivalent arm and the tension of the rope on the pull rope The auxiliary torque on the knee joint was calculated. ,for .

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