Adjustable three-degree-of-freedom ankle joint rehabilitation training robot

Abstract

The adjustable three-degree-of-freedom ankle joint rehabilitation training robot comprises a base, a movable platform, a U-shaped connecting rod, an L-shaped connecting rod, a rotating bracket and a transmission system, the upper end of the rotating bracket is connected with the U-shaped connecting rod through a rotating pair R1 and a rotating pair R2, and the lower end of the rotating bracket is connected with the base through a rotating pair. The movable platform is connected with the U-shaped connecting rod through the L-shaped connecting rod; the transmission system comprises a driver A, a driver B and a driver C. The driver A and the driver B are connected with the movable platform through a first driving branch chain and a second driving branch chain which are symmetrically arranged respectively. The driver C is connected with the revolute pair R2 through a transmission belt; the rotating bracket is fixedly connected with the three drivers; the axes of the rotating pair R1, the rotating pair R2, the rotating pair R3 and the rotating pair R4 intersect at the rotating center. Rotation training in three directions is achieved, and meanwhile flexible rehabilitation posture adjustment can be carried out according to the requirements of a user. The structure is more compact, the size is smaller, and the comfort and safety of rehabilitation training are improved.

Description

Technical Field

[0001] The present invention relates to the field of rehabilitation medical devices, and particularly to a three-degree-of-freedom rotating ankle joint rehabilitation training robot that can be flexibly adjusted, has a compact structure, and is convenient to use. Background Art

[0002] The statements in this part only provide background technical information related to the present disclosure, and these statements may constitute prior art. In the process of implementing the present invention, the inventors found that there are at least the following problems in the prior art.

[0003] Ankle joint rehabilitation robots are mainly used to replace rehabilitation caregivers and help patients complete ankle joint movements. Their main purpose is to restore the muscle strength of the patient's ankle joint through training, enabling the patient to move normally. Medical demonstration and clinical trial research show that muscle vitality can be restored and the central nervous system can be treated through rehabilitation training.

[0004] Currently, ankle joint rehabilitation robots can be mainly divided into two categories: the first category is single-degree-of-freedom ankle joint rehabilitation robots, which have problems such as a single rehabilitation mode; the second category is multi-degree-of-freedom ankle joint rehabilitation robots, and common types include two-degree-of-freedom and three-degree-of-freedom types, which have problems such as non-coincidence of virtual rotation centers, or due to more rods, resulting in a relatively complex and bulky structure.

[0005] For example, in the patent with the application number 201710325074.6 and the patent name "A Parallel Ankle Joint Rehabilitation Device" designed by the applicant, four active branch chains are fixedly arranged on the support platform in a horizontal and staggered arrangement to achieve three-directional rehabilitation movement training. However, the structure of such a scheme is relatively complex and bulky. And due to the relatively complex structure, multi-degree-of-freedom types are usually difficult to flexibly adjust the rehabilitation posture, that is, they cannot flexibly switch between postures such as sitting or lying according to the needs of users, which limits their convenience of use. In addition, the redundant drive method adopted by this patent also increases the complexity of the control system.

[0006] To solve the problem of complex structure, such as the patent with the application number 202310393198.3 and the patent name "A Reconfigurable Ankle Joint Rehabilitation Parallel Mechanism", three active branch chains are used below the moving platform to achieve three-directional rehabilitation movement training. Although the structure is relatively simple, due to the non-coincidence of the virtual rotation center and the inability to match the physiological rotation center of the human ankle joint, it has a certain impact on the comfort and safety during rehabilitation training. And, like the first technology, the above patent is also difficult to flexibly adjust the rehabilitation posture through simple improvement, which also limits the convenience of use.

[0007] How to ensure three - degree - of - freedom ankle joint rehabilitation training to achieve rotational training in three directions, namely ankle dorsiflexion / plantar flexion, inversion / eversion, and internal rotation / external rotation, while also being able to flexibly adjust the rehabilitation posture according to the needs of the user, and meet the comfort and safety during rehabilitation training, as well as the requirement of simple structure, is a problem that the field has been trying to solve. Summary of the Invention

[0008] In view of the above problems, the purpose of the present invention is to solve a part of the problems in the prior art, or at least alleviate these problems.

[0009] An adjustable three - degree - of - freedom ankle joint rehabilitation training robot, comprising:

[0010] A base;

[0011] A moving platform;

[0012] A rotating bracket, the lower end of which is connected to the base through a rotating pair; two support rods are symmetrically fixed at the upper end of the rotating bracket;

[0013] A U - shaped connecting rod, the two ends of which are respectively connected to the two support rods of the rotating bracket through two coaxially arranged rotating pairs R1 and R2;

[0014] An L - shaped connecting rod, one end of which is connected to the middle of the U - shaped connecting rod through a rotating pair R3, and the other end is connected to the moving platform through a rotating pair R4;

[0015] A transmission system, including first and second transmission devices arranged between the moving platform and the base, and a third transmission device arranged outside the U - shaped connecting rod;

[0016] Each of the first and second transmission devices includes a driver and an active branch chain; the active branch chain includes link A and link B; one end of link A is connected to one end of link B through a ball joint, and the other end is connected to the driver through a rotating pair; the other end of link B is connected to the side of the moving platform through a ball joint;

[0017] The third transmission device includes a driver C and a transmission belt; the rotating pair R2 is connected to the driver C through the transmission belt.

[0018] Furthermore, the drivers of the first and second transmission devices are fixedly connected to the lower end of the rotating bracket; the driver C is fixedly connected to the upper end of the rotating bracket.

[0019] Preferably, the first and second transmission devices are symmetrically arranged with respect to the moving platform; the driver A of the first transmission device and the driver B of the second transmission device are coaxially arranged.

[0020] Preferably, the first active chain of the first transmission device has exactly the same structure as the second active chain of the second transmission device.

[0021] Preferably, the other end of the connecting rod A1 of the first active chain is connected to the outside of the actuator A through a revolute pair; the other end of the connecting rod A2 of the second active chain is connected to the outside of the actuator B through a revolute pair.

[0022] Preferably, the other end of the connecting rod B1 of the first active chain is connected to the side surface of the moving platform through a ball joint; the other end of the connecting rod B2 of the second active chain is connected to the side surface of the moving platform through a ball joint.

[0023] The axes of the revolute pairs R1, R2, R3 and R4 intersect at a point, which is the virtual rotation center of the mechanism.

[0024] Furthermore, the axis of the revolute pair R3 is perpendicular to the axes of the revolute pairs R1 and R2; the axis of the revolute pair R4 is perpendicular to the axis of the revolute pair R3.

[0025] Preferably, the other end of the L-shaped connecting rod is connected to the bottom surface of the moving platform through a revolute pair R4.

[0026] The present invention has the following beneficial effects:

[0027] 1. The present invention has three rotational degrees of freedom, which can provide rehabilitation exercise training in three directions, such as dorsiflexion / plantar flexion, inversion / eversion, and internal rotation / external rotation, and can also achieve compound exercise training in multiple directions;

[0028] 2. It has a virtual rotation center, which can match the physiological rotation center of the human ankle joint, improving the comfort and safety of rehabilitation training;

[0029] 3. It is flexible to adjust. Patients can set the most suitable rehabilitation postures according to their own needs, including sitting postures, lying postures, or other postures can be flexibly switched;

[0030] 4. The whole mechanism has fewer rods and a compact structure, so its volume and weight are both small, which is convenient to carry and improves the convenience of use. Description of the Drawings

[0031] Figure 1 is a schematic structural diagram of an embodiment of the present invention;

[0032] Figure 2 is a schematic structural diagram of the base and the rotating bracket of the present invention;

[0033] Figure 3 is a schematic installation diagram of the actuator on the base of the present invention;

[0034] Figure 4 This is a schematic structural diagram of the U-shaped connecting rod and the L-shaped connecting rod of the present invention;

[0035] Figure 5 This is a schematic diagram of the connection between the active branch chain and the moving platform of the present invention;

[0036] Figure 6 This is a schematic diagram of the present invention for sitting posture rehabilitation training;

[0037] Figure 7 This is a schematic diagram of the present invention for lying posture rehabilitation training.

[0038] Wherein: 1 - rotating bracket; 2 - U-shaped connecting rod; 3 - drive A; 4 - drive B; 5 - drive C; 6 - transmission belt; 7 - virtual rotation center; 8 - moving platform; 9 - base; 10 - L-shaped connecting rod; 11 - link A1; 12 - link B1; 13 - link A2; 14 - link B2; 15 - ball hinge; 16 - rotating pair R1; 17 - rotating pair R2; 18 - rotating pair R3; 19 - rotating pair R4. Detailed implementation manners

[0039] The following further describes the present invention with reference to the accompanying drawings. The embodiments of the present invention are only used to illustrate the present invention and not to limit the present invention. Without departing from the technical idea of the present invention, various substitutions and changes made according to the common general knowledge and conventional means in the art shall all be included within the scope of the present invention.

[0040] To solve the above problems, the applicant has conducted in-depth research on the existing technology and found that the reason why the above requirements cannot be met simultaneously is mainly because most of the existing technologies place the active branch chain below the moving platform 8. To achieve rotational training in three directions, at least three active branch chains arranged below the moving platform 8 are required to be movably connected to the moving platform 8 at three different angles. Based on this working principle, almost only fixed rehabilitation postures can be used for training, and it is impossible to flexibly adjust according to different rehabilitation postures, such as sitting postures and lying postures. And it is also difficult to match the virtual rotation center 7 with the physiological rotation center of the human ankle joint based on the above working principle.

[0041] In view of this, through in-depth research and long-term experiments, the applicant proposes a new type of adjustable three-degree-of-freedom ankle rehabilitation training robot, aiming to achieve rotational training in three directions such as ankle dorsiflexion / plantar flexion, inversion / eversion, and internal rotation / external rotation, and at the same time, be able to flexibly adjust the rehabilitation posture according to the needs of the user. The specific solution is as follows.

[0042] As Figure 1 shown, the adjustable three-degree-of-freedom ankle rehabilitation training robot includes:

[0043] Base 9;

[0044] Moving platform 8;

[0045] Rotating bracket 1, the lower end of which is connected to the base 9 through a rotating pair, as Figure 2 shown; Two struts are symmetrically fixed at the upper end of the rotating bracket 1;

[0046] U-shaped connecting rod 2, the two ends of which are respectively connected to the two struts of the rotating bracket 1 through two coaxially arranged rotating pairs R116 and R217, as Figure 3 shown;

[0047] L-shaped connecting rod 10, one end of which is connected to the middle of the U-shaped connecting rod 2 through a rotating pair R318, and the other end is connected to the moving platform 8 through a rotating pair R419, as Figure 4 shown;

[0048] Transmission system, including first and second transmission devices arranged between the moving platform 8 and the base 9, and a third transmission device arranged outside the U-shaped connecting rod 2;

[0049] As Figure 5 shown, both the first and second transmission devices include a driver and a main active chain; The main active chain includes link A and link B; One end of link A is connected to one end of link B through a ball joint 15, and the other end is connected to the driver through a rotating pair; The other end of link B is connected to the side surface of the moving platform 8 through a ball joint 15;

[0050] As Figure 3 shown, the third transmission device includes a driver C5 and a transmission belt 6; The rotating pair R217 is connected to the driver C5 through the transmission belt 6.

[0051] In order to meet the requirements of three-direction rotation training and, at the same time, according to the needs of users, flexible rehabilitation posture adjustment can be carried out. In this application, a rotating bracket 1 that can be adjusted in angle relative to the base 9 is added, and the connection method of the original third main active chain is changed. It is moved from below the moving platform 8 to between the U-shaped connecting rod 2 and the rotating bracket 1, so that this application can not only meet three rotational degrees of freedom, but also enable patients to set the most suitable rehabilitation postures, including sitting postures, lying postures, or other postures can be flexibly switched, as Figure 6 shown in Figure 6 or 7, so as to meet the needs of patients themselves. Moreover, the number of rods of the entire mechanism is small, the structure is compact, so the volume and weight are both small, which is convenient to carry and improves the convenience of use.

[0052] As Figure 3As shown in Fig. 5, the first transmission device and the second transmission device are symmetrically arranged with respect to the moving platform 8; the driver A3 of the first transmission device and the driver B4 of the second transmission device are coaxially arranged. Among them, the first active branch chain of the first transmission device has exactly the same structure as the second active branch chain of the second transmission device, that is, the structural parameters of the connecting rod A111 and the connecting rod A213 are the same, and the structural parameters of the connecting rod B112 and the connecting rod B214 are the same. Two sets of symmetrically arranged and parameter-identical branch chains can obtain a symmetric rotational working space, which is more conducive to the stability of the mechanism during movement, thus ensuring that the virtual rotation center can better match the physiological rotation center of the human ankle joint.

[0053] As Figure 2 shown, the lower end of the rotating bracket 1 is connected to the base 9 through a rotating pair, so that the angle of the rotating bracket 1 relative to the base 9 can be adjusted, as Figure 6 shown in Fig. 6 or Fig. 7. The lower end of the rotating bracket 1 can extend towards the base 9 to form an extension block for fixing the drivers A and B, so that the drivers of the first and second transmission devices can be fixedly connected to the rotating bracket 1. And as Figure 1 shown in Fig. 4 or Fig. 5, preferably, the other end of the connecting rod A111 of the first active branch chain is connected to the outside of the driver A3 through a rotating pair; the other end of the connecting rod A213 of the second active branch chain is connected to the outside of the driver B4 through a rotating pair. By adopting the above method, the volume occupied by the whole mechanism can be made smaller and the structure can be more compact, thus facilitating carrying and improving the convenience of use. It can also make the first and second transmission devices better adapted to the third transmission device more stably to ensure that the virtual rotation center 7 coincides at one point.

[0054] As Figure 5 shown, the other end of the connecting rod B112 of the first active branch chain is connected to the side surface of the moving platform 8 through a ball joint 15; the other end of the connecting rod B214 of the second active branch chain is connected to the side surface of the moving platform 8 through a ball joint 15.

[0055] The driver C5 is fixedly connected to the upper end of the rotating bracket 1, as Figure 3 shown in Fig. 8, and is connected to the rotating pair R2 through a transmission belt 6, so that the rotation of the U-shaped connecting rod 2 relative to the rotating bracket 1 is controlled by the driver C5.

[0056] In order to make the virtual rotation center 7 not only coincide, but also better match the physiological rotation center of the human ankle joint to improve the comfort and safety of rehabilitation training, as Figure 4 shown in Fig. 9, the axes of the rotating pair R116, the rotating pair R217, the rotating pair R318 and the rotating pair R419 intersect at one point, which is the virtual rotation center 7 of the mechanism.

[0057] Furthermore, asFigure 4 As shown, the axis of the revolute pair R318 is perpendicular to the axes of the revolute pairs R116 and R217; the axis of the revolute pair R419 is perpendicular to the axis of the revolute pair R318. Through the arrangement with axes perpendicular to each other pairwise, the singular configurations of the branch chain in the rotational working space can be minimized, that is, the situation where the above axes are coplanar is avoided, and it can well prevent the mechanism from malfunctioning during movement.

[0058] As Figure 1 shown in or 4, the other end of the L-shaped connecting rod 10 is connected to the bottom surface of the moving platform 8 through the revolute pair R419, avoiding affecting the comfort of the patient.

[0059] Working principle:

[0060] As Figure 4 shown, when the moving platform 8 rotates around the axes of the revolute pairs R116 and R217, the dorsiflexion / plantarflexion movement of the ankle joint can be achieved. The movement in this direction is mainly realized by the third transmission device driving the U-shaped connecting rod 2. At this time, the L-shaped connecting rod 10, the first active branch chain and the second active branch chain will move together, and the first active branch chain and the second active branch chain are mainly in the passive mode.

[0061] When the moving platform 8 rotates around the axis of the revolute pair R318, the inversion / eversion movement of the ankle joint can be achieved. At this time, the U-shaped connecting rod 2 remains stationary, while the first active branch chain and the second active branch chain are in the active mode and drive the L-shaped connecting rod 10 to move together.

[0062] When the moving platform 8 rotates around the axis of the revolute pair R419, the internal rotation / external rotation movement of the ankle joint can be achieved, and it is still actively controlled by the first active branch chain and the second active branch chain. Both the U-shaped connecting rod 2 and the L-shaped connecting rod 10 remain stationary.

[0063] From the above analysis, it can be seen that there is a certain decoupling relationship among the three groups of active branch chains. The third transmission device is only related to the dorsiflexion / plantarflexion movement; when performing the inversion / eversion and internal rotation / external rotation movements, it is only related to the first active branch chain and the second active branch chain.

[0064] The present invention has three rotational degrees of freedom, can provide rehabilitation movement training in three directions such as dorsiflexion / plantarflexion, inversion / eversion, and internal rotation / external rotation, and can also achieve compound movement training in multiple directions. And its virtual rotation center matches the physiological rotation center of the human ankle joint, improving the comfort and safety of the rehabilitation training. At the same time, the patient can also set the most suitable rehabilitation posture according to his own needs, including sitting position, lying position, or other postures can be flexibly switched. Moreover, the whole mechanism has fewer rods, a compact structure, so its volume and weight are both small, which is convenient to carry and improves the convenience of use.

[0065] The aforesaid fixed connection without specific designation may be connection means such as riveting, welding, bolt connection, etc., and the movable connection may be connection means such as hinge connection, etc.

Claims

1. An adjustable three-degree-of-freedom ankle rehabilitation training robot, characterized in that, Comprising: Base (9); Moving platform (8); Rotating bracket (1), the lower end of which is connected to the base (9) through a revolute pair; Two struts are symmetrically fixed to the upper end of the rotating bracket (1); U-shaped connecting rod (2), the two ends of which are respectively connected to the two struts of the rotating bracket (1) through two coaxially arranged revolute pairs R1 (16) and R2 (17); L-shaped connecting rod (10), one end of which is connected to the middle part of the U-shaped connecting rod (2) through a revolute pair R3 (18), and the other end of which is connected to the moving platform (8) through a revolute pair R4 (19); Transmission system, including first and second transmission devices arranged between the moving platform (8) and the base (9), and a third transmission device arranged outside the U-shaped connecting rod (2); Both the first and second transmission devices include a driver and a main active chain; The main active chain includes link A and link B; One end of link A is connected to one end of link B through a spherical hinge (15), and the other end is connected to the driver through a revolute pair; The other end of link B is connected to the side surface of the moving platform (8) through a spherical hinge (15); The third transmission device includes a driver C (5) and a transmission belt (6); The revolute pair R2 (17) is connected to the driver C (5) through the transmission belt (6).

2. The adjustable three-degree-of-freedom ankle rehabilitation training robot according to claim 1, wherein The drivers of the first and second transmission devices are fixedly connected to the lower end of the rotating bracket (1); The driver C (5) is fixedly connected to the upper end of the rotating bracket (1).

3. The adjustable three-degree-of-freedom ankle rehabilitation training robot according to claim 1, wherein, 4. The adjustable three-degree-of-freedom ankle rehabilitation training robot according to claim 3, characterized in that, The first transmission device and the second transmission device are symmetrically arranged with respect to the moving platform (8); The driver A (3) of the first transmission device and the driver B (4) of the second transmission device are coaxially arranged.

5. The adjustable three-degree-of-freedom ankle rehabilitation training robot according to claim 4, wherein, The first main active chain of the first transmission device has the same structure as the second main active chain of the second transmission device.

6. The adjustable three-degree-of-freedom ankle rehabilitation training robot according to claim 4, wherein The other end of link A1 (11) of the first main active chain is connected to the outside of the driver A (3) through a revolute pair; The other end of link A2 (13) of the second main active chain is connected to the outside of the driver B (4) through a revolute pair.

7. The adjustable three-degree-of-freedom ankle rehabilitation training robot according to claim 1, characterized in that, The other end of link B1 (12) of the first main active chain is connected to the side surface of the moving platform (8) through a spherical hinge (15); The other end of link B2 (14) of the second main active chain is connected to the side surface of the moving platform (8) through a spherical hinge (15).

8. The adjustable three-degree-of-freedom ankle rehabilitation training robot according to claim 1 or 7, characterized in that, The axes of the revolute pair R1 (16), the revolute pair R2 (17), the revolute pair R3 (18) and the revolute pair R4 (19) intersect at a point, which is the virtual rotation center (7) of the mechanism.

9. The adjustable three-degree-of-freedom ankle rehabilitation training robot according to claim 1, characterized in that, The axis of the revolute pair R3 (18) is perpendicular to the axes of the revolute pair R1 (16) and the revolute pair R2 (17); The axis of the revolute pair R4 (19) is perpendicular to the axis of the revolute pair R3 (18). The other end of the L-shaped connecting rod (10) is connected to the bottom surface of the moving platform (8) through a revolute pair R4 (19).

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