Magnetorheological bearing transmission structure and ankle joint exoskeleton robot

Abstract

The magneto-rheological bearing transmission structure comprises a connecting shaft fixedly connected with the output end of a motor, the top of the connecting shaft is connected with a winding wheel disc through a magneto-rheological bearing, and the periphery of a roller of the magneto-rheological bearing is filled with magneto-rheological fluid and sealed through a sealing ring. A coil is arranged in a top cavity of the winding wheel disc, a winding shell is fixedly connected to the output end face of the motor, and a winding cavity used for taking up and paying off is formed between the winding shell and the winding wheel disc. The magneto-rheological bearing can integrate the clutch function, the design structure is compact, power transmission is only first-stage power transmission from the connecting shaft to the winding wheel disc, efficiency loss can be reduced, and therefore the power transmission control efficiency of the ankle joint exoskeleton robot can be improved; due to the clutch function of the wire winding wheel disc, the wire winding wheel disc and the connecting shaft rotate in a separated mode, so that a wearer does not have extra loads in the non-assistance stage, interference of the exoskeleton to the human body is reduced to the minimum, and comfort is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to exoskeleton robot technical field, concretely relates to a kind of magneto-rheological bearing transmission structure and ankle exoskeleton robot, for rehabilitation training or motion power assistance. BACKGROUND

[0002] Ankle exoskeleton robot is a wearable assistive device, mainly used for rehabilitation training such as gait recovery of stroke patients or used for motion power assistance such as enhancing walking / running efficiency;The power transmission mode in ankle exoskeleton robot plays a crucial role, the traditional power transmission mode is to provide power output torque by motor rotation, thereby tightening the inner line of Bowden cable, driving ankle synchronous movement to achieve power assistance effect,

[0003] And motor rotation carries out power transmission process, such as the patent "magneto-rheological power control motor and control method" with publication number CN103280943B in prior art, drive shaft connects clutch shell, clutch shell is composed of clutch shell cover and clutch shell body, output shaft passes through clutch and is fixed with clutch piece, clutch piece front and back are respectively provided with front clutch coil and rear clutch coil, sealing cavity is filled with magneto-rheological fluid, gap is controlled within 2mm, the solidification degree of magneto-rheological fluid is controlled by coil current, realizes torque transmission or interruption;But there are the following defects in use process: one is that the structure of the power transmission mode is complex, needs to rely on clutch piece, clutch shell cover and clutch shell and double-sided coil to realize clutch, and precise assembly is needed between components, and operation is very inconvenient;Two is that the power transmission mode has power transmission redundancy, such as power needs to be transmitted through drive shaft→drive front bearing→second clutch bearing→clutch shell body→clutch piece→clutch shell cover→first clutch bearing→output shaft multistage transmission, efficiency loss is significant, which affects the power transmission control efficiency of ankle exoskeleton robot. UTILITY MODEL CONTENTS

[0004] The utility model aims at providing a kind of magneto-rheological bearing transmission structure to solve the problem of poor application effect of traditional power transmission mode.

[0005] The purpose of the utility model can be realized by the following technical solutions:

[0006] A kind of magneto-rheological bearing transmission structure, including the connecting shaft being fixed with the motor output end, the top of the connecting shaft is connected with the winding wheel disc by magnetic fluid bearing, the roller around the magnetic fluid bearing is filled with magneto-rheological fluid, and is sealed by sealing ring, sealing ring is arranged on the upper and lower end faces of magnetic fluid bearing, and the top opening cavity of winding wheel disc is provided with coil, the motor output end surface is fixedly connected with winding shell, and the winding cavity for taking up and paying off wire is arranged between winding shell and winding wheel disc;

[0007] When the coil is electrified, the magnetic flux of the magnetorheological fluid is formed into a magnetic chain of a magnetorheological bearing by a magnetic field around the coil, and the connecting shaft is fixedly connected with the winding wheel disc through the magnetorheological bearing.

[0008] When the coil is de-energized, the connecting shaft is rotatably connected with the winding wheel disc through the magnetorheological bearing.

[0009] As a further scheme of the utility model, the motor output disc is fixedly connected to the output end face of the motor, and the motor output disc is adaptively inserted and connected to the bottom opening cavity of the winding wheel disc.

[0010] As a further scheme of the utility model, the motor output disc is fixedly connected to the output end face of the motor, and the motor output disc is adaptively inserted and connected to the bottom opening cavity of the winding wheel disc.

[0011] As a further scheme of the utility model, the motor output disc is fixedly connected to the output end face of the motor, and the motor output disc is adaptively inserted and connected to the bottom opening cavity of the winding wheel disc.

[0012] As a further scheme of the utility model, the motor output disc is fixedly connected to the output end face of the motor, and the motor output disc is adaptively inserted and connected to the bottom opening cavity of the winding wheel disc.

[0013] As a further scheme of the utility model, the motor output disc is fixedly connected to the output end face of the motor, and the motor output disc is adaptively inserted and connected to the bottom opening cavity of the winding wheel disc.

[0014] The ankle joint exoskeleton robot comprises the magnetorheological bearing transmission structure and a drive control box, the magnetorheological bearing transmission structure is arranged in the drive control box, and the drive control box is connected with an ankle joint unit through Bowden wires.

[0015] The magnetorheological bearing transmission structure transmits power to the ankle joint unit through the Bowden wires, so that the ankle joint of the wearer is driven to move.

[0016] As a further scheme of the utility model, the drive control box is fixedly connected to a harness.

[0017] As a further scheme of the utility model, the steel wire inside the Bowden wire is connected with the ankle joint unit through a tension sensor.

[0018] As a further scheme of the utility model, the ankle joint unit is provided with an inertia sensor for collecting gait information of the wearer.

[0019] The utility model has the advantages of the following:

[0020] (1) In the power transmission design process of the application, the power of the connecting shaft is transmitted to the winding wheel disc through the magnetorheological bearing, the magnetorheological bearing can integrate the clutch function, the design structure is compact, the power transmission is only one-stage power transmission from the connecting shaft to the winding wheel disc, the efficiency loss can be reduced, and thus the power transmission control efficiency of the ankle exoskeleton robot is improved;

[0021] (2) In the power transmission design process of the application, the clutch function of the winding wheel disc is separated from the connecting shaft, for example, when the wearer is in the non-assisted period of the gait swing phase, the motor is free to rotate, and the resistance problem caused by the reverse traction of the steel wire rope in the traditional rope traction system can be completely solved, so that the wearer has no additional load in the non-assisted stage, the interference of the exoskeleton to the human body is reduced to the minimum, and the comfort is improved.

[0022] (3) When the magnetorheological bearing integrates the clutch function, the motor output disc is connected with the connecting shaft through the coil spring, and the pre-tightening force of the coil spring can provide progressive torque transmission to eliminate the jerk problem caused by the phase change delay of the magnetorheological liquid, so that the coil spring is used for the effect of buffering the power transmission impact and compensating the micro-torque fluctuation. BRIEF DESCRIPTION OF DRAWINGS

[0023] The utility model will be further described in connection with the drawings.

[0024] Figure 1 It is a structure schematic view of a magnetorheological bearing transmission structure of the utility model;

[0025] Figure 2 It is a split schematic view of a magnetorheological bearing transmission structure of the utility model;

[0026] Figure 3 It is a cross-sectional schematic view of a magnetorheological bearing transmission structure of the utility model;

[0027] Figure 4 It is a structure schematic view of an ankle exoskeleton robot of the utility model;

[0028] Figure 5 It is a schematic view of the magnetorheological bearing transmission structure arranged in the drive control box of an ankle exoskeleton robot of the utility model;

[0029] Figure 6 It is an ankle unit structure schematic view of an ankle exoskeleton robot of the utility model.

[0030] In the figure: 1, motor; 2, winding shell; 3, winding wheel; 4, winding cavity; 5, entry wire rack; 50, pulley; 51, limit wire sleeve; 6, connecting shaft; 7, magnetorheological bearing; 8, coil; 9, coil end cover; 10, motor output disc; 11, coil spring; 12, flange bearing; 13, drive control box; 14, back strap; 15, Bowden wire; 150, steel wire; 151, tension sensor; 16, ankle joint unit; 160, inertia sensor. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0032] In the description of the present application, it should be understood that the terms indicating the position or location relationship are based on the position or location relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as a limitation on the present application; in the description of the present application, the meaning of "a plurality of" and "several" is at least two, such as two, three, etc., unless otherwise explicitly specified.

[0033] Please refer to Figures 1 to 3 The utility model discloses a magnetorheological bearing transmission structure, including with motor 1 output fixed connection connecting shaft 6, motor 1 output passes through connecting shaft 6 and carries out power transmission design process, the top of connecting shaft 6 is connected with winding wheel 3 through magnetorheological bearing 7, the roller around magnetorheological bearing 7 fills magnetorheological fluid, and is sealed through sealing ring, and sealing ring is arranged on the upper and lower end surfaces of magnetorheological bearing 7, and the top cavity of winding wheel 3 is equipped with coil 8, and motor 1 output surface is fixedly connected with winding shell 2, and winding shell 2 is equipped with winding cavity 4 for taking up and paying off wire between winding shell 2 and winding wheel 3.

[0034] In the power transmission design process of the application, the power of the connecting shaft 6 is transmitted to the winding wheel disc 3 through the magnetorheological bearing 7. The magnetorheological bearing 7 can integrate the clutch function, and the design structure is compact. The inner diameter ring of the structure of the magnetorheological bearing 7 is connected with the top of the connecting shaft 6 in interference fit, the outer diameter ring is connected with the top cavity of the winding wheel disc 3 in interference fit, and the rollers between the inner diameter ring and the outer diameter ring are designed to rotate. When the coil 8 is electrified, the magnetic field around the coil 8 makes the magnetorheological fluid solidify to form a magnetic chain, so that the inner and outer rings of the magnetorheological bearing 7 are relatively locked, so as to realize the fixed connection of the connecting shaft 6 and the winding wheel disc 3 through the magnetorheological bearing 7. When the connecting shaft 6 rotates, the winding wheel disc 3 rotates integrally. The winding wheel disc 3 can be used to pull the steel wire 150 inside the Bowden cable 15 in the ankle exoskeleton robot, so as to drive the wearer's ankle plantar flexion movement. The power transmission of the application is only one-stage power transmission from the connecting shaft 6 to the winding wheel disc 3, which can reduce the efficiency loss, thereby helping to improve the power transmission control efficiency of the ankle exoskeleton robot.

[0035] In the power transmission design process of the application, when the coil 8 is de-energized, the magnetorheological fluid loses the effect of the magnetic chain, and the magnetorheological bearing 7 plays the role of a conventional rotating support connection. The connecting shaft 6 is connected with the winding wheel disc 3 through the magnetorheological bearing 7, and the winding wheel disc 3 is separated from the connecting shaft 6. When the wearer is in the non-assisted period of gait swing phase, the motor 1 is free to rotate, which can completely solve the problem of resistance caused by reverse traction of the steel wire rope in the traditional rope traction system, so that the wearer has no additional load in the non-assisted stage, the interference of the exoskeleton to the human body is minimized, and the comfort is improved.

[0036] In the specific embodiment, when the connecting shaft 6 and the winding wheel disc 3 are installed, the motor output disc 10 is fixedly connected to the output end surface of the motor 1. The motor output disc 10 can be fixedly installed with the motor 1 through the countersunk screws in the circumferential direction. The motor output disc 10 is inserted and connected with the bottom cavity of the winding wheel disc 3. The motor output disc 10 plays a role in stably supporting the rotation of the winding wheel disc 3, ensuring stable and reliable rotation. The shaft center position of the motor output disc 10 is rotatably connected with the connecting shaft 6 through the flange bearing 12, so that the bottom of the connecting shaft 6 is rotatably connected and designed stably and reliably.

[0037] When the magnetorheological bearing 7 of the application integrates the clutch function design, the coil spring 11 is arranged in the groove cavity of the motor output disc 10. The coil spring 11 is sleeved with the connecting shaft 6. The coil spring 11 can be an elastic member with a spiral laminated structure, so that the outermost end of the coil spring 11 is fixed with the side wall of the groove cavity of the motor output disc 10, and the innermost end is in pre-tightening contact with the connecting shaft 6. The pre-tightening force of the coil spring 11 can provide progressive torque transmission to eliminate the problem of delay caused by the phase change of the magnetorheological fluid, so as to realize the effect of the coil spring 11 in buffering the impact of power transmission and compensating the micro-torque fluctuation.

[0038] In the process of installing the coil 8 in the application, the coil 8 is sleeved on the protruding column end of the coil end cover 9, the protruding column end of the coil end cover 9 abuts against the top end face of the connecting shaft 6, and is fixedly connected with the winding wheel disc 3. The top end of the winding wheel disc 3 can be designed with a notch to facilitate the current lead connection of the coil 8. The circumferential sidewall of the top end of the winding wheel disc 3 can be designed with a threaded connection screw to facilitate the screw and the protruding column end of the coil end cover 9 to be tightly locked, thereby playing a safety protection role.

[0039] When the winding cavity 4 formed between the winding shell 2 and the winding wheel disc 3 in the application is designed, the winding cavity 4 is provided with an inlet wire rack 5 on one side. The inlet wire rack 5 is fixedly connected to the output end face of the motor 1, and a pulley 50 and a limiting wire sleeve 51 are rotatably connected to the inlet wire rack 5. The steel wire 150 inside the Bowden wire 15 can be guided into the winding cavity 4 through the pulley 50 to realize the traction and collection of the winding wheel disc 3. The limiting wire sleeve 51 can prevent the steel wire 150 from being separated from the pulley 50, thereby ensuring the traction quality of the steel wire 150 in the winding cavity 4.

[0040] Referring to Figure 4 and Figure 5 It is shown that the utility model also proposes an ankle joint exoskeleton robot, including above-mentioned magnetorheological bearing transmission structure, and drive control box 13, magnetorheological bearing transmission structure sets up in drive control box 13, drive control box 13 is connected with ankle joint unit 16 through Bowden wire 15, wherein magnetorheological bearing transmission structure passes through Bowden wire 15 and transmits power to ankle joint unit 16, and drives the ankle joint movement of wearer.

[0041] In the use process of the ankle joint exoskeleton robot of the application, the drive control box 13 can be arranged on the harness 14, and the drive control box 13 can be fixed by sewing a cloth cover. The harness 14 is used to be carried on the back of the wearer, so that the drive control box 13 is as close to the center of gravity of the human body as possible, which can reduce the negative impact of the device on the walking process. The outer wire sleeve of the Bowden wire 15 can be connected to the drive control box 13 and the ankle joint unit 16 through the connecting head. One end of the steel wire 150 inside the Bowden wire 15 can be pulled by the winding wheel disc 3 in the magnetorheological bearing 7 transmission structure. The other end of the steel wire 150 is connected to the ankle joint unit 16 through the tension sensor 151, so as to realize the flexible traction of the ankle joint unit 16 by the Bowden wire 15.

[0042] As Figure 6As shown, the ankle joint unit 16 is provided with an inertia sensor 160 for collecting the gait information of the wearer, and the control motion technical scheme of the ankle exoskeleton robot of the application is as follows: the gait characteristics of the human body can be collected through the inertia sensor 160 and the tension sensor 151, so as to judge the physiological state and motion intention of the wearer, and the gait analysis is carried out through the upper computer controller in the driving control box 13, and the online algorithm optimization is carried out at the same time, the assistance strategy is formulated, the command is sent to the motor 1 for execution, so as to realize the metatarsophalangeal flexion assistance mode of the ankle joint, and the control motion technical scheme belongs to the prior art, and the specific reference can be made to the patent with the publication number CN109662869B, "a wearable flexible lower limb assistance robot", the paragraph 0050 of the patent specification discloses the control motion technical scheme.

[0043] The above describes one embodiment of the present application in detail, but the content described is only the preferred embodiment of the present application, and cannot be considered as limiting the scope of the present application. Any equivalent changes and improvements made within the scope of the present application should still belong to the patent coverage of the present application.

Claims

1. A magnetorheological bearing transmission structure, comprising a connecting shaft (6) fixedly connected to an output end of a motor (1), characterized in that: The top of the connecting shaft (6) is connected to the winding wheel (3) via a magnetorheological bearing (7); magnetorheological fluid is filled around the roller of the magnetorheological bearing (7) and sealed by a sealing ring; the sealing ring is arranged on the upper and lower end surfaces of the magnetorheological bearing (7); a coil (8) is provided in the top cavity of the winding wheel (3); a winding housing (2) is fixedly connected to the output end surface of the motor (1); and a winding cavity (4) for reeling in and out the wire is provided between the winding housing (2) and the winding wheel (3); When the coil (8) is energized, the magnetorheological fluid is transformed into a magnetic flux of the magnetorheological bearing (7) through the magnetic field around the coil (8), and the connecting shaft (6) is fixedly connected to the winding wheel (3) through the magnetorheological bearing (7); When the coil (8) is powered off, the connecting shaft (6) is rotationally connected to the winding wheel (3) via the magnetorheological bearing (7).

2. The magnetorheological bearing transmission structure according to claim 1, characterized in that: A motor output disc (10) is fixedly connected to the output end face of the motor (1), and the motor output disc (10) is adapted to be plugged and connected to the bottom cavity of the winding wheel (3).

3. The magnetorheological bearing transmission structure according to claim 2, characterized in that: The motor output disc (10) is rotatably connected to the connecting shaft (6) via a flange bearing (12) at the axis center position.

4. The magnetorheological bearing transmission structure according to claim 3, characterized in that: A coil spring (11) is provided in the groove cavity of the motor output disk (10), and the coil spring (11) is sleeve-connected to the connecting shaft (6).

5. The magnetorheological bearing transmission structure according to claim 1, characterized in that: The coil (8) is sleeved and connected to the raised column end of the coil end cover (9), the raised column end of the coil end cover (9) is in contact with the top end surface of the connecting shaft (6), and is fixedly connected to the winding wheel (3).

6. The magnetorheological bearing transmission structure according to claim 1, characterized in that: An inlet bobbin (5) is provided on one side of the winding chamber (4). The inlet bobbin (5) is fixedly connected to the output end face of the motor (1), and a connecting pulley (50) and a limiting wire sleeve (51) are rotatably connected on the inlet bobbin (5).

7. An ankle exoskeleton robot, characterized in that: The invention comprises a magnetorheological bearing transmission structure according to any one of claims 1 to 6, and a drive control box (13), wherein the magnetorheological bearing transmission structure is arranged in the drive control box (13), and the drive control box (13) is connected to the ankle joint unit (16) through a Bowden cable (15); The magnetorheological bearing transmission structure transmits power to the ankle joint unit (16) through the Bowden cable (15), thereby driving the wearer's ankle joint to move.

8. The ankle exoskeleton robot according to claim 7, characterized in that: The drive control box (13) is fixedly connected to the shoulder strap (14).

9. The ankle exoskeleton robot according to claim 7, characterized in that: The steel wire (150) inside the Bowden cable (15) is connected to the ankle joint unit (16) via a tension sensor (151).

10. The ankle exoskeleton robot according to claim 7, characterized in that: The ankle joint unit (16) is provided with an inertia sensor (160) for collecting gait information of the wearer.

Images