Rope-driven joint and robot

Abstract

The invention discloses a rope-driven joint and a robot, and belongs to the technical field of robots. In the rope-driven joint, one end of a torque sensor is overlapped with a driven wheel, the other end of the torque sensor is fixedly connected with a rotating shaft, and the torque sensor is arranged in a non-contact mode with a bearing of the driven wheel, so that the structure of the rope-driven joint is more compact; the torque measurement precision is more accurate; in addition, the rotating shaft is divided into the large shaft and the small shaft, and the large shaft and the small shaft are installed in a matched mode through the non-circular shaft, so that the overall installation is simpler, the structural machining difficulty is lower, and large-scale production and assembly can be achieved easily.

Description

Technical Field

[0001] This application belongs to the technical field of robots, and particularly relates to a cable-driven joint and a robot. Background Art

[0002] In recent years, with the development of robot technology, exoskeleton robots and rehabilitation robots have been increasingly widely used in enhancing human motor ability, assisting in rehabilitation training, etc. Such robots usually adopt a cable-driven method to effectively support and control human joints through light and flexible ropes. To ensure the safety and comfort of human-robot interaction and achieve compliant control, it is particularly important to accurately detect the driving torque of the cable-driven joint.

[0003] In the prior art, in the field of collaborative robots, joint torque sensors are often designed to be coaxially installed with motors. However, for a cable-driven structure, the driven pulley is not coaxially aligned with the motor, and the structure of the driven pulley is compact, making it difficult to integrate a torque sensor therein.

[0004] Therefore, how to integrate a torque sensor in the driven pulley to accurately detect the driving torque of the cable-driven joint has become a key problem to be solved urgently. Summary of the Invention

[0005] In view of the above problems, the present invention aims to provide a cable-driven joint, which includes an innovative torque detection scheme that particularly takes into account the compact structure of the driven pulley and can effectively improve the accuracy and reliability of torque detection without significantly increasing the system complexity and cost, thereby promoting the further development and application of exoskeleton robots and rehabilitation robots.

[0006] In the first aspect of this application, a cable-driven joint is disclosed, which includes a driving component, a driven component, and a driving cable; The driving component drives the driven component to move through the driving cable; The driven component includes a driven pulley and a torque sensor, and one end of the torque sensor is nested inside the driven pulley and fixedly connected to the driven pulley.

[0007] Further, the torque sensor is set as a beam connection structure with rings. Two rings are arranged on both sides of the torque sensor, and multiple connecting beams are arranged in the middle.

[0008] Further, the driven component further includes a rotating shaft, and the rotating shaft includes a large shaft and a small shaft. The large shaft and the small shaft are in interference fit through a non-circular structure to realize the overall fixed connection of the driving shaft.

[0009] Further, a fixing hole is arranged on the large shaft, and the other end of the torque sensor is fixedly connected to the large shaft through the fixing hole.

[0010] Furthermore, the large shaft is provided with a first circular shaft and a non-circular hole embedded in the circular shaft, the small shaft is provided with a second circular shaft and a non-circular shaft extending out of the circular shaft, and the non-circular hole is in interference fit with the non-circular shaft.

[0011] Furthermore, a threaded hole is provided on the first circular shaft for fixing the non-circular shaft to the non-circular hole.

[0012] Furthermore, the rotating shaft further includes a bearing, the inner ring of the bearing is in interference fit with the second circular shaft of the small shaft, and the inner ring of the driven wheel is in interference fit with the outer ring of the bearing.

[0013] Furthermore, the cable-driven joint further includes a support device, the support device is rotatably connected to the drive shaft of the driven wheel for supporting the driven wheel.

[0014] Furthermore, the small shaft is provided with a flange for connecting the load.

[0015] In the second aspect of the present application, the present application discloses a robot, which includes the cable-driven joint according to any one of the first aspect.

[0016] The present application discloses a cable-driven joint and a robot. The cable-driven joint uses a drive cable to connect the driven wheel and the drive wheel, overlaps and fixes one end of the driven wheel with a torque sensor, and the other end is fixedly connected to a bearing and then arranged on a rotating shaft. One end of the rotating shaft is fixedly connected to the torque sensor, and the other end is fixedly connected to the load, realizing accurate measurement of the torque of the drive wheel during the driving process. Description of the Drawings

[0017] Figure 1 Schematic diagram of the overall structure of the cable-driven joint; Figure 2 Schematic diagram of the overall structure of the driven component; Figure 3 Schematic diagram of the torque sensor; Figure 4 Schematic diagram of the structure of the large shaft of the rotating shaft; Figure 5 Schematic diagram of the structure of the small shaft of the rotating shaft; Figure 6 Schematic diagram of the structure of the driven component on the large shaft side; Figure 7 Schematic diagram of the structure of the driven component without the driven wheel and the torque sensor; Figure 8 Schematic diagram of the structure of the driven component on the small shaft side. Detailed Description of the Embodiments

[0018] Next, in combination with the accompanying drawings in the embodiments of the present application, the technical solutions in the embodiments of the present application will be further clearly and completely described. It should be noted that the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work belong to the scope of protection of the present application.

[0019] In order to make the invention purpose, technical solutions and advantages of the present application clearer, the technical solutions of the present invention will be clearly and completely described below in combination with the accompanying drawings and specific implementation solutions. It should be pointed out that for those of ordinary skill in the art, several changes and improvements can be made without departing from the concept of the present invention, and these all belong to the scope of protection of the present application.

[0020] In recent years, with the development of robot technology, exoskeleton robots and rehabilitation robots have been increasingly widely used in improving human motor ability, assisting rehabilitation training, etc. Such robots usually adopt a cable-driven method to effectively support and control human joints through light and flexible ropes. In order to ensure the safety and comfort of human-machine interaction and achieve compliant control, it is particularly important to accurately detect the driving torque of the cable-driven joint.

[0021] In the prior art, in the field of collaborative robots, joint torque sensors are often designed to be coaxially installed with the motor. However, for a cable-driven structure, the driven pulley is not coaxially arranged with the motor, and the structure of the driven pulley is compact, making it difficult to integrate a torque sensor therein.

[0022] Therefore, how to integrate a torque sensor in the driven pulley to achieve accurate detection of the driving torque of the cable-driven joint has become a key problem to be solved urgently.

[0023] In view of the above problems, the present invention aims to provide a cable-driven joint, which includes an innovative torque detection solution. This solution particularly considers the compact structure of the driven pulley and can effectively improve the accuracy and reliability of torque detection without significantly increasing the system complexity and cost, thereby promoting the further development and application of exoskeleton robots and rehabilitation robots.

[0024] As Figure 1 shown, a cable-driven joint includes a driving component 1, a driven component 2, and a driving rope (not shown in the figure). The driving component 1 drives the driven component 2 to move through the driving rope. The driving component 1 includes a driving wheel 11 and a driving motor 12. The driving wheel 11 moves under the action of the driving motor 12 and drives the driven component 2 to move through the driving rope. The cable-driven joint further includes a load, and the load is connected to the driven component 2 and drives the load to move under the action of the driven component 2.

[0025] In this embodiment, the driving rope can be a tungsten wire rope, a steel wire rope or other similar ropes. The purpose of the driving rope is to drive the movement of the driven component through the movement of the driving wheel 12. At the same time, the driving rope has certain stiffness requirements and will not be broken by the driven component or load within a certain force range.

[0026] In Figure 2 it, the driven component 2 includes a driven wheel 21, a torque sensor 22 and a rotating shaft 23. A part of the torque sensor 22 is overlapped with the driven wheel 21, that is, a part of the torque sensor 22 and a part of the driven wheel 21 overlap axially. One end of the torque sensor 22 is fixedly connected to one end of the driven wheel 21, and the other end is fixed to the rotating shaft 23. By overlapping the torque sensor 22 with the driven wheel 21, compared with the traditional coaxial installation of the torque sensor and the driven wheel, the axial dimension of the driven component can be shortened. At the same time, the overlapping setting of the torque sensor 22 and the driven wheel 21 makes the torque sensor 22 closer to the measurement object, and the measurement accuracy and reliability are greatly improved. When the driving wheel 12 drives the driven wheel 21 to move, the driven wheel 21 will also drive the torque sensor 22 to move together.

[0027] As Figure 3 shown, in an embodiment of the present application, the torque sensor 22 is set as a beam connection structure with rings. Two rings are arranged on both sides of the torque sensor, that is, the first ring 221 and the second ring 222, and a plurality of connecting beams 223 are arranged in the middle. The number of connecting beams can be set as needed. To ensure the measurement accuracy and the convenience of data processing, the plurality of connecting beams are equidistantly arranged on the rings, and the strain gauges of the torque sensor are arranged on the connecting beams. A threaded hole is arranged on the first ring 221 of the torque sensor, and the first ring of the torque sensor is fixedly connected to one end of the driven wheel.

[0028] As Figure 4 shown, in an embodiment of the present application, the rotating shaft 23 includes a large shaft 231 and a small shaft 232. The large shaft 231 and the small shaft 232 are detachably connected through a non-circular shaft. The large shaft 231 is provided with a first circular shaft 2311, and a non-circular hole 2312 is recessed inward at one end of the first circular shaft 2311. The small shaft 232 is provided with a second circular shaft 2321, and a non-circular shaft 2322 protrudes outward from the second circular shaft 2321. The large shaft 231 and the small shaft 232 are connected and fixed through the cooperation of the non-circular hole 2312 and the non-circular shaft 2322. To ensure the integrity and stability of the rotating shaft 23, a fixing hole 2313 is also arranged on the first circular shaft 2311, and a fixing member is arranged in the fixing hole 2313 to fix the non-circular shaft 2322 to the inner wall of the non-circular hole 2312 to avoid the displacement of the large shaft 231 and the small shaft 232. By detachably fixing the large shaft 231 and the small shaft 232 to form the rotating shaft 23, the assembly efficiency and the manufacturing cost can be greatly improved.

[0029] As Figure 5 shown, in one embodiment of the present application, the other end of the torque sensor 22 is fixedly connected to the large shaft 231. Specifically, the second ring 232 of the torque sensor 23 is fixedly connected to the large shaft 231. Thus, when the driven wheel 21 drives the torque sensor 23 to move, the large shaft 231 can be driven to move together.

[0030] Furthermore, as Figure 6 shown, the small shaft 232 is further provided with a bearing 2323, and the bearing 2323 is fixedly connected to the second round shaft 2321. Specifically, the two are connected by interference fit. The inner ring of the end of the driven wheel 21 fixedly connected to the torque sensor 22 is in interference fit with the bearing 2323, thereby realizing the fixed connection among the end of the driven wheel 21 fixedly connected to the torque sensor 22, the bearing 2323, and the small shaft 232. To avoid affecting the torque measurement, the bearing 2323 does not contact the torque sensor 22. In practical applications, the driven wheel 21 is a hollow structure, and one end of the driven wheel 21 is provided with a screw hole for fixedly connecting with the torque sensor 22. The end face of this end of the driven wheel 21 extends inward to form a ring surface 211, and the inner diameter of the ring surface 211 is smaller than the inner diameter of other parts of the driven wheel. The bearing 2323 is in interference fit with the ring surface 211, realizing the fixed connection among the driven wheel 21, the torque sensor 22, the bearing 2323, and the small shaft 232.

[0031] As Figure 7 shown, the small shaft 232 is further provided with a flange 2324. The flange 2324 is arranged outside the driven wheel 21, and the load is fixedly connected to the flange 2324, realizing the movement of the driven wheel 21 driving the load.

[0032] As Figure 1 shown, in one embodiment of the present application, the cable-driven joint further includes a support structure 4. The support structure 4 is rotatably connected to both ends of the rotating shaft 23 for supporting the driven component 2. An angle sensor 41 is further arranged at the rotating connection of the support structure 4 and the large shaft 231 for measuring the rotation angle of the driven wheel. Rotating bearings are arranged at both ends of the rotating shaft 23, and the support structure is rotatably connected to both ends of the rotating shaft through the rotating bearings.

[0033] In another embodiment of the present application, the present application discloses a robot including the cable-driven joint in the first embodiment, and the cable-driven joint can be one or more. It should be noted that the robot in this embodiment can be an exoskeleton robot or other collaborative robots, and all robots using the cable-driven joint are within this scope.

[0034] The present application discloses a cable-driven joint and a robot, belonging to the technical field of robots. In the cable-driven joint of the present application, one end of the torque sensor is overlapped with the driven wheel, and the other end is fixedly connected to the rotating shaft. The torque sensor is arranged in non-contact with the bearing of the driven wheel, making the structure of the cable-driven joint more compact and the accuracy of torque measurement more accurate. In addition, the rotating shaft is divided into a large shaft and a small shaft, and is installed by non-circular shaft fitting, making the overall installation simpler and the structural processing difficulty lower, which helps to achieve large-scale production and assembly.

Claims

1. A cable-driven joint, characterized in that, It includes a driving component, a driven component and a driving rope; The driving component drives the driven component to move through the driving rope; The driven component includes a driven wheel and a torque sensor. One end of the torque sensor is nested inside the driven wheel and fixedly connected to the driven wheel.

2. The cable-driven joint according to claim 1, characterized in that, The torque sensor is arranged in a beam connection structure with a ring. There are two rings arranged on both sides of the torque sensor, and multiple connecting beams are arranged in the middle.

3. The cable-driven joint according to claim 2, characterized in that, The driven component further includes a rotating shaft. The rotating shaft includes a large shaft and a small shaft. The large shaft and the small shaft are in interference fit through a non-circular structure to achieve the overall fixed connection of the driving shaft.

4. The cable-driven joint according to claim 3, characterized in that, There is a fixing hole arranged on the large shaft, and the other end of the torque sensor is fixedly connected to the large shaft through the fixing hole.

5. The cable-driven joint according to claim 3, characterized in that, The large shaft is provided with a first circular shaft and a non-circular hole embedded in the circular shaft. The small shaft is provided with a second circular shaft and a non-circular shaft extending outside the circular shaft. The non-circular hole and the non-circular shaft are in interference fit.

6. The cable-driven joint according to claim 5, characterized in that, There is a threaded hole arranged on the first circular shaft for fixing the non-circular shaft in the non-circular hole.

7. The cable-driven joint according to claim 6, characterized in that, The rotating shaft further includes a bearing. The inner ring of the bearing is in interference fit with the second circular shaft of the small shaft, and the inner ring of the driven wheel is in interference fit with the outer ring of the bearing.

8. The cable-driven joint according to claim 7, characterized in that, The rope-driven joint further includes a supporting device. The supporting device is rotatably connected to the driving shaft of the driven wheel for supporting the driven wheel.

9. The cable-driven joint according to claim 7, characterized in that, The small shaft is provided with a flange, and the flange is used to connect a load.

10. A robot, characterized in that, It includes at least one rope-driven joint according to any one of claims 1-9.

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