A rigid-flexible coupled knee joint assisted movement robot

Abstract

The present invention provides a rigid-flexible coupled knee joint assisted movement robot, comprising a rigid-flexible integrated bidirectional bending driver, a thigh wearing mechanism and a calf wearing mechanism, wherein: the rigid-flexible integrated bidirectional bending driver includes a first airbag and a second airbag for realizing the bending degrees of freedom on both sides of the knee joint. By filling air pressure into the first airbag and / or the second airbag, bending deformation and bending moment are generated, and the bending moment is transmitted to the lower limb of the user through the thigh wearing mechanism and the calf wearing mechanism; the ends of the first airbag and the second airbag are both provided with conical fasteners for sealing the ends of the first airbag and the second airbag, and the rigid-flexible integrated bidirectional bending driver is respectively connected to the thigh wearing mechanism and the calf wearing mechanism through the conical fasteners. The present invention can realize the adaptive matching of the rotation center of the robot with the knee joint axis of the user, and realize the efficient torque conduction of the robot, and has the advantages of comfortable wearing, safety, convenience, etc.

Description

Technical Field

[0001] The present invention relates to the technical field of rigid-flexible coupling robots, and specifically, to a rigid-flexible coupling knee joint assisted movement robot. Background Art

[0002] For a long time, wearable assistive robots have been a hot research object in academic and commercial research. As one of the largest and most complex joints in the human body, the knee joint is very vulnerable to diseases such as arthritis. Therefore, knee joint assisted movement robots have received great attention. Most traditional knee joint assisted movement robots are designed with a rigid structure, and the joint torque is provided by hydraulic pressure or motors. Such rigid knee joint assisted movement robots have the advantages of mature manufacturing and control technologies, high operation accuracy, and large output torque, but they also face problems such as being bulky, uncomfortable to wear, and the rotation center not matching the human joint rotation axis.

[0003] In recent years, the development of the field of soft robots has brought new ideas to assistive movement robots. The soft characteristics of soft robots can solve problems such as uncomfortable wearing of traditional rigid robots and the rotation center not matching the rotation axis of human joints, greatly improving the safety and wearing comfort of wearable assistive robots.

[0004] In recent years, soft assistive movement robots represented by tendon-driven soft robots and muscle-driven soft robots have begun to appear. Tendon-driven soft robots refer to robots that use soft materials as artificial tendons and complete the movement assistance function by stretching the limbs at both ends of the user's joint. Common artificial tendon materials include cables, ropes, and shape memory alloys. For example, a tendon-driven hand exoskeleton developed by Luca Randazzo et al. at the Federal Polytechnic School of Lausanne drives the fingers to complete the bending movement through artificial tendons fixed at both ends of the finger joints. Tendon-driven soft robots have the advantages of being light and having a long service life. However, at the same time, since the force application point acts on the limbs at both ends of the joint rather than the joint itself, it is easy to generate shear force on the moving limbs, further compressing the joint, and facing challenges in safety and wearing comfort. Muscle-driven soft robots refer to robots that use soft actuators as artificial muscles, attach them to human joints, and provide torque for joint movement through pneumatic or motor drive, without generating a large shear force on the limbs. For example, the Wyss Institute for Biologically Inspired Engineering at Harvard University designed an artificial muscle-driven knee joint assist device, which embeds multiple small pneumatic artificial muscles in an elastomer and controls the movement form of the elastomer by inflating different pneumatic artificial muscles. The soft characteristics of muscle-driven soft robots themselves also solve problems such as uncomfortable wearing of traditional rigid robots and the rotation center not matching the joint rotation axis, but at the same time, there are also problems such as short service life and small driving torque.

[0005] The Chinese invention patent with the application publication number CN110638605A discloses a rigid-flexible integrated lower limb exoskeleton. Through the combination of a joint pneumatic soft actuator and a rigid connecting rod, the lower limb exoskeleton can not only assist the wearer in joint movement at the human joints but also adapt to the changes in the human joint axes. At non-joint positions, the deformation profile of the lower limb exoskeleton is made consistent with the movement profile of the human lower limb. However, the driving torque and the maximum working air pressure of the actuator in this patent need to be further improved, and the actuator in this patent cannot be used independently of the exoskeleton, which limits its application scenarios. Summary of the Invention

[0006] Aiming at the defects in the prior art, the purpose of the present invention is to provide a rigid-flexible coupled knee joint assisted movement robot.

[0007] According to one aspect of the present invention, there is provided a rigid-flexible coupled knee joint assisted movement robot, including a rigid-flexible integrated bidirectional bending actuator, a thigh wearing mechanism, and a calf wearing mechanism, wherein:

[0008] The thigh wearing mechanism and the calf wearing mechanism are used to wear the robot on the lower limbs of the user; the rigid-flexible integrated bidirectional bending actuator is connected between the thigh wearing mechanism and the calf wearing mechanism;

[0009] The rigid-flexible integrated bidirectional bending actuator includes symmetrically arranged first airbag and second airbag. The first airbag and the second airbag are respectively used to achieve the bending degrees of freedom on both sides of the knee. By filling air pressure into the first airbag and / or the second airbag, bending deformation and bending torque are generated, and the bending torque is transmitted to the lower limbs of the user through the thigh wearing mechanism and the calf wearing mechanism;

[0010] Conical fasteners are provided at the ends of the first airbag and the second airbag. The conical fasteners are used to seal the ends of the first airbag and the second airbag, and the rigid-flexible integrated bidirectional bending actuator is connected to the thigh wearing mechanism and the calf wearing mechanism respectively through the conical fasteners.

[0011] Optionally, the first airbag and the second airbag have the same structure, and both are semi-elliptical cylindrical flexible airbags.

[0012] Optionally, the first airbag and the second airbag are configured to be able to respectively achieve a bending deformation of more than 90° independently, and the length of the plane of the semi-elliptical cylindrical flexible airbag does not change during inflation deformation.

[0013] Optionally, the semi-elliptical cylindrical flexible airbag includes a central restraint layer and an external restraint layer. The central restraint layer is disposed at the lateral plane of the semi-elliptical cylindrical flexible airbag to restrict deformation at the plane of the semi-elliptical cylindrical flexible airbag. The external restraint layer is disposed at the lateral curved surface of the semi-elliptical cylindrical flexible airbag to restrict tangential deformation at the curved surface of the semi-elliptical cylindrical flexible airbag. The central restraint layer and the external restraint layer are sewn and connected at the junction of the plane and the curved surface on the side of the semi-elliptical cylindrical flexible airbag.

[0014] Optionally, the robot has one or more of the following options:

[0015] - The semi-elliptical cylindrical flexible airbag is made of silicone;

[0016] - The central restraint layer is made of a polyester fiber woven fabric coated with polyvinyl chloride;

[0017] - The external restraint layer is made of a knitted fabric of rubber mixed with polyester fiber.

[0018] Optionally, the conical fastener includes an inner conical fastener and an outer conical fastener. The inner conical fastener is placed inside the semi-elliptical cylindrical flexible airbag. The main body of the inner conical fastener is a conical structure, and a cylindrical part with threads is provided at the end. The main body of the outer conical fastener is two symmetrically distributed conical structures, which are sleeved outside the semi-elliptical cylindrical flexible airbag. The round hole at the end of the outer conical fastener is sleeved on the cylindrical part with threads at the end of the inner conical fastener and fixed by a nut;

[0019] Both ends of the outer conical fastener are provided with screw holes. The thigh wearing mechanism and the calf wearing mechanism are respectively connected to the screw holes on the outer conical fastener through fasteners to ensure efficient torque transmission of the robot.

[0020] Optionally, the outer conical fastener is sleeved outside the central restraint layer and the external restraint layer. The cylindrical part with threads at the end of the inner conical fastener extends out through the round hole at the end of the outer conical fastener. A nut is installed on the cylindrical part with threads of the inner conical fastener, and the inner conical fastener, the semi-elliptical cylindrical flexible airbag, the central restraint layer and the external restraint layer, and the outer conical fastener are compacted and sealed through the conical surface of the conical fastener from inside to outside to seal the two ends of the semi-elliptical cylindrical flexible airbag and ensure the airtightness of the rigid-flexible integrated bidirectional bending actuator.

[0021] Optionally, the thigh wearing mechanism includes a thigh clamping device and a thigh guide rod. The thigh guide rod includes a first thigh guide rod and a second thigh guide rod. The first thigh guide rod and the second thigh guide rod are arranged in parallel. The thigh clamping device is fixed to the thigh guide rod by a nut, and the position of the thigh clamping device on the thigh guide rod is adjustable;

[0022] The calf wearing mechanism includes a calf clamping device and a calf guide rod. The calf guide rod includes a first calf guide rod and a second calf guide rod. The first calf guide rod and the second calf guide rod are arranged in parallel. The calf clamping device is fixed to the calf guide rod by a nut, and the position of the calf clamping device on the calf guide rod is adjustable.

[0023] Optionally, both the first airbag and the second airbag are provided with an air path interface for inflating air pressure at one end and a pressure sensor interface at the other end. The pressure sensor interface is used to connect a pressure sensor.

[0024] Optionally, a thigh nine-axis WIFI gyroscope is provided on the thigh wearing mechanism, and a calf nine-axis WIFI gyroscope is provided on the calf wearing mechanism. The real-time motion posture of the robot is fed back through the thigh nine-axis WIFI gyroscope and the calf nine-axis WIFI gyroscope.

[0025] Compared with the prior art, the present invention has at least one of the following beneficial effects:

[0026] The knee joint assisted movement robot provided by the present invention adopts a rigid-flexible coupling structural design. The flexible driving airbag of the rigid-flexible integrated bidirectional bending driver ensures that its bending axis (the rotation center of the robot) can be adaptively matched with the knee joint axis of the user, enabling the assisted movement robot to adapt to users of different body sizes and improving the universality of the robot; through the mutual cooperation of the rigid conical fastener of the rigid-flexible integrated bidirectional bending driver, the thigh wearing mechanism and the calf wearing mechanism, efficient torque transmission of the robot can be ensured, and at the same time, it has the advantages of light weight, comfortable, safe and convenient wearing. Description of the Drawings

[0027] By reading the detailed description of the non-limiting embodiments with reference to the following drawings, other features, objects and advantages of the present invention will become more obvious:

[0028] Figure 1 It is a schematic diagram of the overall structure of the rigid-flexible coupling knee joint assisted movement robot in an embodiment of the present invention:

[0029] Figure 2 It is a schematic exploded view of the structure of the rigid-flexible coupling knee joint assisted movement robot in an embodiment of the present invention;

[0030] In the figure: 1 is the thigh clamping device, 2 is the nine-axis WIFI gyroscope for the thigh, 3A is the first thigh guide rod, 3B is the second thigh guide rod, 4 is the rigid-flexible integrated bidirectional bending driver, 5A is the first calf guide rod, 5B is the second calf guide rod, 6 is the calf clamping device, 7 is the nine-axis WIFI gyroscope for the calf, 8 is the flexible thigh strap, 9 is the flexible calf strap, 4-1 is the air path interface, 4-2 is the inner conical fastener, 4-3 is the outer conical fastener, 4-4 is the first airbag, 4-4’ is the second airbag, 4-5 is the air pressure sensor interface, 4-6 is the central limiting layer, and 4-7 is the external restraint layer. Specific Embodiment

[0031] The present invention will be described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that those of ordinary skill in the art can make several deformations and improvements without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0032] Referring to Figure 1-2 , a rigid-flexible coupled knee joint assisted movement robot provided by an embodiment of the present invention is worn at the knee of a user. The robot includes a rigid-flexible integrated bidirectional bending driver 4, a thigh wearing mechanism, and a calf wearing mechanism, wherein: the thigh wearing mechanism and the calf wearing mechanism are used to wear the robot on the lower limbs of the user; the rigid-flexible integrated bidirectional bending driver 4 is connected between the thigh wearing mechanism and the calf wearing mechanism; the rigid-flexible integrated bidirectional bending driver 4 includes symmetrically arranged first airbag 4-4 and second airbag 4-4’. The first airbag 4-4 and the second airbag 4-4’ are respectively used to realize the bending degrees of freedom on both sides of the knee. By filling air pressure into the first airbag 4-4 and / or the second airbag 4-4’, bending deformation and bending moment are generated. The bending moment is transmitted to the lower limbs of the user through the thigh wearing mechanism and the calf wearing mechanism; both ends of the first airbag 4-4 and the second airbag 4-4’ are provided with conical fasteners, and the conical fasteners are used to seal the ends of the first airbag 4-4 and the second airbag 4-4’. The rigid-flexible integrated bidirectional bending driver 4 is connected to the thigh wearing mechanism and the calf wearing mechanism respectively through the conical fasteners.

[0033] In the embodiment of the present invention, the flexible inflatable bending part (i.e., the flexible part, the airbag part) of the rigid-flexible integrated bidirectional bending actuator 4 generates bending deformation and bending moment through inflation. The bending moment is transmitted to the user's thigh and calf through the rigid moment conduction part (i.e., the rigid part, the conical fastener) of the actuator, the thigh wearing mechanism and the calf wearing mechanism, so as to assist the human body to realize knee joint movement. The embodiment of the present invention adopts the design idea of rigid-flexible coupling, which not only retains the characteristics of good fit of the robot, the rotation axis (rotation center) can adaptively match the human knee joint axis (rotation shaft), and comfortable and safe wearing, but also has the characteristics of large driving torque of the rigid robot, high moment conduction efficiency, and long service life.

[0034] In some embodiments, both the first airbag 4-4 and the second airbag 4-4' are provided with an air path interface 4-1 for filling air pressure at one end and a pressure sensor interface 4-5 at the other end. The pressure sensor interface 4-5 is used to connect a pressure sensor. Specifically, the inflation interface and the pressure sensor interface 4-5 are respectively arranged on the conical fasteners at both ends.

[0035] In some embodiments, the thigh-wearing mechanism includes a thigh clamping device 1, a thigh flexible strap 8, and a thigh guide rod. The thigh guide rod includes a first thigh guide rod 3A and a second thigh guide rod 3B. The first thigh guide rod 3A and the second thigh guide rod 3B are arranged in parallel. The thigh clamping device 1 is fixed to the thigh guide rod by a nut. The position of the thigh clamping device 1 on the two guide rods is adjustable according to the user's body size, so that it can be freely adjusted on the thigh guide rod. The thigh flexible strap 8 is fixed to one side of the thigh clamping device 1. The calf-wearing mechanism includes a calf clamping device 6, a calf flexible strap 9, and a calf guide rod. The calf guide rod includes a first calf guide rod 5A and a second calf guide rod 5B. The first calf guide rod 5A and the second calf guide rod 5B are arranged in parallel. The calf clamping device 6 is fixed to the calf guide rod by a nut. The position of the calf clamping device 6 on the two guide rods is adjustable according to the user's body size, so that it can be freely adjusted on the calf guide rod. The calf flexible strap 9 is fixed to one side of the calf clamping device 6, on the same side of the robot as the thigh flexible strap 8. Each tapered fastener includes an inner tapered fastener 4-2 and an outer tapered fastener 4-3. The main body of the inner tapered fastener 4-2 is a tapered structure, placed inside the first airbag 4-4 or the second airbag 4-4'. Both ends are provided with cylindrical parts with threads for connection to the gas path interface 4-1. The cylindrical part is hollow-designed to ensure that gas can be filled. The main body of the outer tapered fastener 4-3 is two symmetrically distributed tapered structures, sleeved outside the first airbag 4-4 and the second airbag 4-4'. The round holes at both ends of the outer tapered fastener 4-3 are respectively sleeved on the cylindrical parts with threads at the ends of the inner tapered fastener 4-2, and the two are tightly assembled together through the threads on the cylindrical part with a nut. Screw holes are provided at both ends of the outer tapered fastener 4-3. The thigh-wearing mechanism and the calf-wearing mechanism are respectively connected to the screw holes on the outer tapered fastener 4-3 through fasteners; specifically, the guide rods of the thigh-wearing mechanism and the calf-wearing mechanism are respectively fixed and installed to the rigid-flexible integrated bidirectional bending actuator through the screw holes on the outer tapered fastener 4-3 with bolts and nuts.

[0036] In the above embodiments, the thigh clamping device 1 and the calf clamping device 6 have the same structure but different sizes. The two guide rods of the thigh wearing mechanism and the two guide rods of the calf wearing mechanism are both made of carbon fiber. The cross-sectional diameters of the two guide rods of the thigh wearing mechanism and the two guide rods of the calf wearing mechanism are the same but the lengths are different. The thigh flexible strap 8 and the calf flexible strap 9 have the same structure but different lengths. The thigh wearing mechanism and the calf wearing mechanism are made by 3D printing with PLA material and are respectively fixed to the user's thigh and calf through the corresponding clamping devices and flexible straps. The thigh wearing mechanism and the calf wearing mechanism are both configured to be adjustable in the installation position. Specifically, the user can adjust the installation position of the clamping device along the guide rod according to the user's body size to adjust the relative positions of the thigh wearing mechanism, the calf wearing mechanism and the rigid-flexible integrated bidirectional bending actuator 4, align the center of the rigid-flexible integrated bidirectional bending actuator 4 with the knee joint axis, and complete the wearing work of the rigid-flexible coupled knee joint assistive movement robot, so as to adapt to users of different body sizes and improve the universality of the robot.

[0037] After the rigid-flexible coupled knee joint assistive movement robot in the above embodiments is worn, the air pressure can be filled into one side or both sides of the airbag of the rigid-flexible integrated bidirectional bending actuator 4 to cause the actuator to generate bending deformation and bending moment, and the bending moment is transmitted to the user's lower limb through the thigh wearing mechanism and the calf wearing mechanism to realize the knee joint assistive movement.

[0038] In some embodiments, the first airbag 4-4 and the second airbag 4-4' are symmetrically distributed and have the same structure, and are both semi-elliptical cylindrical flexible airbags. The semi-elliptical cylindrical design enables the natural bending angle of the airbag to be well matched with the natural bending angle of the human knee joint. Preferably, the semi-elliptical cylindrical flexible airbag is made of silicone, such as addition-cured silicone. In some other embodiments, the first airbag 4-4 and the second airbag 4-4' can also be made of other types of flexible materials.

[0039] In some embodiments, the rigid-flexible integrated bidirectional bending actuator 4 is configured to be able to generate a bending deformation of more than 90° when inflated to assist the knee joint in daily rehabilitation training, and the length of the plane of the semi-elliptical cylindrical flexible airbag does not change during inflation deformation. The two flexible airbags cooperate with each other to achieve the bidirectional bending effect of the rigid-flexible integrated bidirectional bending actuator 4 in the initial state.

[0040] In some embodiments, the semi-elliptical cylindrical flexible airbag includes a central restraint layer 4-6 and an outer restraint layer 4-7. The central restraint layer 4-6 and the outer restraint layer 4-7 wrap the semi-elliptical cylindrical flexible airbag to restrict its bending motion posture and limit the deformation of the airbag. Among them, the central restraint layer 4-6 is disposed at the lateral plane of the semi-elliptical cylindrical flexible airbag to restrict the deformation at the plane of the semi-elliptical cylindrical flexible airbag; the outer restraint layer 4-7 is disposed at the lateral curved surface of the semi-elliptical cylindrical flexible airbag to restrict the tangential deformation at the curved surface of the semi-elliptical cylindrical flexible airbag. The central restraint layer 4-6 and the outer restraint layer 4-7 are sewn and connected by sewing thread at the junction of the plane and the curved surface on the side of the semi-elliptical cylindrical flexible airbag.

[0041] In some embodiments, the central restraint layer 4-6 is made of a non-stretchable material such as a polyester fiber woven fabric coated with polyvinyl chloride; the outer restraint layer 4-7 is made of a unidirectionally stretchable material such as a knitted fabric of rubber mixed with polyester fiber. Thereby, when the airbag is inflated and expanded, it can perform axial bending deformation to the greatest extent, and avoid the deformation of the rigid-flexible integrated bidirectional bending actuator 4 in other directions, so that the rigid-flexible coupled knee joint assisted movement robot has the advantages of a large bending deformation range and no torsional deformation. Of course, in some other embodiments, the central restraint layer 4-6 and the outer restraint layer 4-7 can also be made of other types of materials, as long as the same functions can be achieved.

[0042] In some embodiments, for the double-airbag parallel pneumatic actuator symmetrically distributed on the left and right, the semi-elliptical cylindrical flexible airbag, the central restraint layer 4-6 and the outer restraint layer 4-7 are tightly fixed and fitted through a tapered fastener and a nut. The inner tapered fastener 4-2 is placed inside the semi-elliptical cylindrical flexible airbag, the central restraint layer 4-6 and the outer restraint layer 4-7 are wrapped outside the semi-elliptical cylindrical flexible airbag, and the outer tapered fastener 4-3 is installed outside the central restraint layer 4-6 and the outer restraint layer 4-7. The cylindrical part with threads of the inner tapered fastener 4-2 extends out through the round hole at the end of the outer tapered fastener 4-3, and the nut is installed on the cylindrical part with threads of the inner tapered fastener 4-2. From the inside to the outside, the inner tapered fastener 4-2, the semi-elliptical cylindrical flexible airbag, the central restraint layer 4-6 / outer restraint layer 4-7 and the outer tapered fastener 4-3 are compacted and sealed through the conical surface of the tapered fastener to seal the two ends of the semi-elliptical cylindrical flexible airbag, avoid the surface junction line at the edge of the airbag, and ensure the bending motion posture and airtightness of the rigid-flexible integrated bidirectional bending actuator 4.

[0043] In the rigid-flexible integrated bidirectional bending actuator 4 in the above embodiments, through the design concept of pneumatic drive - airbag inflation - fabric restraint, a large-angle bidirectional bending design of the actuator is achieved. The airbag, the central restraint layer 4-6, and the outer restraint layer 4-7 are tightly connected by tapered fasteners, ensuring the airtightness of the airbag. At the same time, the tapered fasteners replace the bottom surface of the airbag to seal the airbag, removing the boundary intersection line of the side surface that is extremely prone to damage in the traditional airbag, greatly improving the maximum bearing air pressure and service life of the rigid-flexible integrated bidirectional bending actuator 4. The thigh wearing mechanism and the calf wearing mechanism are fixed to the tapered fasteners by nuts, which can ensure the efficient torque transmission of the robot.

[0044] In the above embodiments, when the airbag on the front side of the user is inflated and the airbag on the back side is not inflated, the rigid-flexible integrated bidirectional bending actuator 4 generates a torque in the direction of knee joint flexion and extension movement to help the user achieve knee joint flexion and extension movement. When both the airbag on the front side and the airbag on the back side of the rigid-flexible integrated bidirectional bending actuator 4 are inflated, the rigid-flexible integrated bidirectional bending actuator 4 bends at any required angle within the maximum bending range to assist in fixing the knee joint at the any required angle. When the airbag on the front side of the rigid-flexible integrated bidirectional bending actuator 4 is not inflated and the airbag on the back side is inflated, the rigid-flexible integrated bidirectional bending actuator 4 generates a torque in the direction of knee joint extension movement to help the user achieve knee joint extension movement.

[0045] In some embodiments, a thigh nine-axis WIFI gyroscope 2 is provided on the thigh wearing mechanism. The thigh nine-axis WIFI gyroscope 2 is fixed to the thigh clamping device 1 by nuts. A calf nine-axis WIFI gyroscope 7 is provided on the calf wearing mechanism. The calf nine-axis WIFI gyroscope 7 is fixed to the calf clamping device 6 by nuts. The thigh nine-axis WIFI gyroscope 2 and the calf nine-axis WIFI gyroscope 7 can adopt the same structural model. By connecting a pressure sensor to monitor the real-time working air pressure of the first airbag 4-4 and the second airbag 4-4', the air pressure filled into the airbag is controlled. Through the mutual cooperation of the thigh nine-axis WIFI gyroscope 2 and the calf nine-axis WIFI gyroscope 7, the real-time motion posture of the robot is fed back. Thus, the user can view the air pressure in the airbag of the rigid-flexible integrated bidirectional bending actuator through an external pressure sensor at any time, and at the same time, the air pressure filled into the airbag can be adjusted in a timely manner according to the real-time motion posture data fed back by the two gyroscopes.

[0046] The above embodiments of the present invention adopt the design concept of rigid-flexible integration. The rigid-flexible integrated bidirectional bending actuator includes a flexible part (double airbags symmetrically distributed on the left and right) and a rigid torque conduction part (conical fastener). The combination of the two not only ensures the advantages of the soft robot, such as safe and comfortable wearing, light weight, high flexibility, and the ability of the actuator rotation center to adaptively match the knee joint rotation axis, but also has the advantages of the rigid robot, such as large output torque, high torque conduction efficiency, long service life, and convenient wearing. Overall, it improves the driving efficiency, service life, and wearing safety of the knee joint assistive movement robot.

[0047] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various deformations or modifications within the scope of the claims, which do not affect the essence of the present invention. The above preferred features can be used in any combination without conflict.

Claims

1. A rigid-flexible coupled knee joint assisted movement robot, characterized in that, It includes a rigid-flex integrated bidirectional bending actuator, a thigh wearing mechanism, and a calf wearing mechanism, where: The thigh wearing mechanism and the calf wearing mechanism are used to wear the robot on the user's lower limbs; the rigid-flex integrated bidirectional bending actuator is connected between the thigh wearing mechanism and the calf wearing mechanism; The rigid-flex integrated bidirectional bending actuator includes symmetrically arranged first airbag and second airbag. The first airbag and the second airbag are respectively used to achieve the bending degrees of freedom on both sides of the knee. By filling air pressure into the first airbag and / or the second airbag, bending deformation and bending moment are generated, and the bending moment is transmitted to the user's lower limbs through the thigh wearing mechanism and the calf wearing mechanism; Conical fasteners are provided at the ends of the first airbag and the second airbag. The conical fasteners are used to seal the ends of the first airbag and the second airbag. The rigid-flex integrated bidirectional bending actuator is respectively connected to the thigh wearing mechanism and the calf wearing mechanism through the conical fasteners.

2. The rigid-flexible coupled knee joint assisted movement robot according to claim 1, characterized in that, The first airbag and the second airbag have the same structure, both being semi-elliptical cylindrical flexible airbags.

3. The rigid-flexible coupled knee joint assisted movement robot according to claim 2, characterized in that, The first airbag and the second airbag are configured to be able to respectively achieve bending deformation exceeding 90° independently, and the length of the plane of the semi-elliptical cylindrical flexible airbag does not change during inflation deformation.

4. The rigid-flexible coupled knee joint assisted movement robot according to claim 2, characterized in that, The semi-elliptical cylindrical flexible airbag includes a central limiting layer and an external binding layer. The central limiting layer is arranged at the side plane of the semi-elliptical cylindrical flexible airbag to limit the deformation of the plane of the semi-elliptical cylindrical flexible airbag; the external binding layer is arranged at the side curved surface of the semi-elliptical cylindrical flexible airbag to limit the tangential deformation of the curved surface of the semi-elliptical cylindrical flexible airbag. The central limiting layer and the external binding layer are sewn and connected at the junction of the plane and the curved surface on the side of the semi-elliptical cylindrical flexible airbag.

5. The rigid-flexible coupled knee joint assisted movement robot according to claim 4, characterized in that, There are one or more of the following options: - The semi-elliptical cylindrical flexible airbag is made of silicone; - The central limiting layer is made of a polyester fiber woven fabric coated with polyvinyl chloride; - The external binding layer is made of a knitted fabric of rubber mixed with polyester fiber.

6. The rigid-flexible coupled knee joint assisted movement robot according to claim 4, characterized in that, The conical fastener includes an inner conical fastener and an outer conical fastener. The inner conical fastener is placed inside the semi-elliptical cylindrical flexible airbag. The main body of the inner conical fastener is a conical structure, and a cylindrical part with threads is provided at the end; The main body of the outer conical fastener is two symmetrically distributed conical structures, which are sleeved outside the semi-elliptical cylindrical flexible airbag. The round hole at the end of the outer conical fastener is sleeved on the cylindrical part with threads at the end of the inner conical fastener and is fixed by a nut; Screw holes are provided at both ends of the outer conical fastener. The thigh wearing mechanism and the calf wearing mechanism are respectively connected to the screw holes on the outer conical fastener through fasteners to ensure efficient torque conduction of the robot.

7. The rigid-flexible coupled knee joint assisted movement robot according to claim 6, characterized in that, The outer conical fastener is sleeved outside the central limiting layer and the outer binding layer, and the cylindrical part with threads at the end of the inner conical fastener extends out through the round hole at the end of the outer conical fastener; the nut is installed on the cylindrical part with threads of the inner conical fastener, and from the inside to the outside, the inner conical fastener, the semi-elliptical flexible airbag, the central limiting layer and the outer binding layer, and the outer conical fastener are compacted and sealed through the conical surface of the conical fastener to seal the two ends of the semi-elliptical flexible airbag, ensuring the airtightness of the rigid-flexible integrated bidirectional bending actuator.

8. The rigid-flexible coupled knee joint assisted movement robot according to claim 1, characterized in that, The thigh wearing mechanism includes a thigh clamping device and a thigh guide rod. The thigh guide rod includes a first thigh guide rod and a second thigh guide rod. The first thigh guide rod and the second thigh guide rod are arranged in parallel. The thigh clamping device is fixed to the thigh guide rod by a nut, and the position of the thigh clamping device on the thigh guide rod is adjustable; The calf wearing mechanism includes a calf clamping device and a calf guide rod. The calf guide rod includes a first calf guide rod and a second calf guide rod. The first calf guide rod and the second calf guide rod are arranged in parallel. The calf clamping device is fixed to the calf guide rod by a nut, and the position of the calf clamping device on the calf guide rod is adjustable.

9. The rigid-flexible coupled knee joint assisted movement robot according to claim 1, characterized in that, Both the first airbag and the second airbag are provided with an air passage interface for inflating air pressure at one end and a pressure sensor interface at the other end. The pressure sensor interface is used to connect a pressure sensor.

10. The rigid-flexible coupled knee joint assisted movement robot according to claim 9, characterized in that, The thigh wearing mechanism is provided with a thigh nine-axis WIFI gyroscope, and the calf wearing mechanism is provided with a calf nine-axis WIFI gyroscope. The real-time motion posture of the robot is fed back through the thigh nine-axis WIFI gyroscope and the calf nine-axis WIFI gyroscope.

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