Rope-driven joint module, mechanical arm and robot

Abstract

The invention discloses a rope-driven joint module, a mechanical arm and a robot, and belongs to the technical field of robots. The rope-driven joint module comprises a first joint part and a second joint part, two first driving ropes are symmetrically distributed relative to the center rod, and two second driving ropes are symmetrically distributed relative to the center rod; the connecting line of the two first driving ropes and the two connecting points of the first joint part forms a first rotating axial direction, the connecting line of the two second driving ropes and the two connecting points of the first joint part forms a second rotating axial direction, and the first rotating axial direction and the second rotating axial direction are vertically intersected at the center of the end part of the first joint part; wherein the second joint part is used for rotating in the axial direction of the first rotating shaft to achieve first-degree-of-freedom rotation, and the second joint part is used for rotating in the axial direction of the second rotating shaft to achieve second-degree-of-freedom rotation. Two-degree-of-freedom rotation of the rope-driven joint module is decoupled, and the flexibility of joint driving of the rope-driven joint module is high.

Description

Technical Field

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

[0002] In recent years, cable-driven joint mechanisms have been widely used in the field of robotics due to their advantages such as light weight, high flexibility, and long power transmission time.

[0003] Since a rope can only provide tensile force and not supporting force, the number of driving ropes should be at least greater than the dimension of the joint degrees of freedom. For example, at least n + 1 driving ropes are required for a fully driven cable-driven joint with n degrees of freedom.

[0004] Currently, a cable-driven joint with two degrees of freedom usually has three driving ropes. The three driving ropes are distributed pairwise in different planes to achieve driving with two degrees of freedom. However, in this case, the driving with two degrees of freedom is highly coupled, the flexibility of joint driving is limited, and an additional coordination control mechanism needs to be set up to ensure the geometric constraints of the joint. Summary of the Invention

[0005] This application aims to solve at least one of the technical problems existing in the prior art. For this purpose, this application provides a cable-driven joint module, a robotic arm, and a robot, in which the rotations with two degrees of freedom are decoupled and the flexibility of joint driving is high.

[0006] In a first aspect, this application provides a cable-driven joint module, including:

[0007] A first joint part and a second joint part;

[0008] A driving module, the driving module includes a central rod, two first driving ropes, and two second driving ropes. The two ends of the central rod are respectively arranged at the central positions of the ends of the first joint part and the second joint part;

[0009] Both ends of each first driving rope are respectively arranged at the ends of the first joint part and the second joint part, and the two first driving ropes are symmetrically distributed with respect to the central rod; both ends of each second driving rope are respectively arranged at the ends of the first joint part and the second joint part, and the two second driving ropes are symmetrically distributed with respect to the central rod;

[0010] The connection line of the two connection points of the two first driving ropes and the first joint part forms a first rotation axis, and the connection line of the two connection points of the two second driving ropes and the first joint part forms a second rotation axis. The first rotation axis and the second rotation axis are perpendicular to each other and intersect at the central position of the end of the first joint part;

[0011] Among them, the second joint part is used to rotate along the first rotation axis to achieve the first-degree-of-freedom rotation, and the second joint part is used to rotate along the second rotation axis to achieve the second-degree-of-freedom rotation.

[0012] According to the cable-driven joint module of the present application, by setting two pairs of drive cable pairs, two first drive cables are arranged on both sides of the central rod to form the first rotation axis, and two second drive cables are arranged on both sides of the central rod to form the second rotation axis. The two rotation axes are perpendicular to each other and intersect at the central rod to achieve two-degree-of-freedom rotation. For each degree of freedom, the two-way rotation of the degree of freedom is controlled by two cables, and the two-degree-of-freedom rotation is decoupled, and the flexibility of the joint drive of the cable-driven joint module is high.

[0013] According to an embodiment of the present application, the drive module further includes:

[0014] A first drive device, the first ends of the two first drive cables are wound around the output end of the first drive device, the second ends of the two first drive cables are connected to the second joint part, and the first drive device is arranged on the first joint part.

[0015] According to an embodiment of the present application, the first drive device is used to drive the second joint part to rotate along the second rotation axis through the two first drive cables, and the length of the second drive cable between the first joint part and the second joint part is equal to the length of the central rod.

[0016] According to an embodiment of the present application, the drive module further includes:

[0017] A second drive device, the first ends of the two second drive cables are wound around the output end of the second drive device, the second ends of the two second drive cables are connected to the second joint part, and the second drive device is arranged on the first joint part.

[0018] According to an embodiment of the present application, the second drive device is used to drive the second joint part to rotate along the first rotation axis through the two second drive cables, and the length of the first drive cable between the first joint part and the second joint part is equal to the length of the central rod.

[0019] According to an embodiment of the present application, the end of the first joint part facing the second joint part is a plane, and the end of the second joint part facing the first joint part is a plane.

[0020] According to an embodiment of the present application, one end of the central rod is hinged to the first joint part, and the other end of the central rod is fixedly connected to the second joint part.

[0021] According to an embodiment of the present application, one end of the central rod is provided with a spherical hinge structure, and one end of the central rod is hinged to the first joint portion through the spherical hinge structure.

[0022] In a second aspect, the present application provides a robotic arm, including:

[0023] At least one rope-driven joint module as described in the above first aspect.

[0024] In a third aspect, the present application provides a robot, including:

[0025] At least one robotic arm as described in the above second aspect.

[0026] The additional aspects and advantages of the present application will be partially given in the following description, partially become apparent from the following description, or be understood through the practice of the present application. Description of the Drawings

[0027] The above and / or additional aspects and advantages of the present application will become apparent and be easily understood from the description of the embodiments in conjunction with the following drawings, where:

[0028] Figure 1 is one of the schematic structural diagrams of the rope-driven joint module provided by the embodiment of the present application;

[0029] Figure 2 is another schematic structural diagram of the rope-driven joint module provided by the embodiment of the present application;

[0030] Figure 3 is a schematic diagram of the plane where the first driving rope of the rope-driven joint module provided by the embodiment of the present application is located;

[0031] Figure 4 is a schematic diagram of the plane where the second driving rope of the rope-driven joint module provided by the embodiment of the present application is located;

[0032] Figure 5 is a third schematic structural diagram of the rope-driven joint module provided by the embodiment of the present application;

[0033] Figure 6 is a fourth schematic structural diagram of the rope-driven joint module provided by the embodiment of the present application;

[0034] Figure 7 is a fifth schematic structural diagram of the rope-driven joint module provided by the embodiment of the present application;

[0035] Figure 8 is a sixth schematic structural diagram of the rope-driven joint module provided by the embodiment of the present application;

[0036] Figure 9It is a schematic flowchart of the cam profile design method for the cable-driven joint module provided by the embodiment of the present application;

[0037] Figure 10 It is a schematic diagram of the cam profile of the optimization target coefficient provided by the embodiment of the present application;

[0038] Figure 11 It is a schematic structural diagram of the cam profile design device for the cable-driven joint module provided by the embodiment of the present application;

[0039] Figure 12 It is a schematic structural diagram of the electronic device provided by the embodiment of the present application.

[0040] Reference numerals:

[0041] The first joint part 100, the first joint end part 110, the second joint part 200, the second joint end part 210, the drive cable 300, the first drive cable 310, the second drive cable 320, the central rod 410, the spherical hinge structure 411,

[0042] The drive motor 510, the rotating wheel 521, the cam 522, the follower 523, the contact point 524, the tension pre-tightening device 530. Detailed implementation manners

[0043] Next, the technical solutions in the embodiments of the present application will be clearly described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are 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 of ordinary skill in the art belong to the scope of protection of the present application.

[0044] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, rather than to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present application can be implemented in an order other than those illustrated or described herein, and the objects distinguished by "first", "second", etc. generally belong to the same category, and the number of objects is not limited. For example, the first object can be one or multiple. In addition, "and / or" in the specification and claims means at least one of the connected objects, and the character " / " generally represents an "or" relationship between the associated objects before and after.

[0045] Next, in conjunction with the accompanying drawings, the cable-driven joint module, the robotic arm, the robot, the cam profile design method for the cable-driven joint module, the electronic device, and the readable storage medium provided by the embodiments of the present application will be described in detail through specific embodiments and their application scenarios.

[0046] The embodiment of the present application provides a cable-driven joint module, in which the rotations of the two degrees of freedom of the joint are decoupled, and the flexibility of joint driving is high.

[0047] As Figure 1 shown, the cable-driven joint module includes: a first joint part 100, a second joint part 200, and a driving module. Among them, the driving module includes a central rod 410, two first driving cables 310, and two second driving cables 320.

[0048] In this embodiment, both ends of the central rod 410 are respectively arranged at the center of the ends of the first joint part 100 and the second joint part 200, and the central rod 410 is supported between the first joint part 100 and the second joint part 200.

[0049] In some embodiments, the end of the first joint part 100 facing the second joint part 200 is a plane, and the end of the second joint part 200 facing the first joint part 100 is a plane.

[0050] It should be noted that the central rod 410 is supported between the first joint part 100 and the second joint part 200, leaving a space for the second joint part 200 to rotate relative to the first joint part 100. The opposite end faces of the two joint parts do not need to be set as arc surfaces convenient for pivoting, and the smooth rotation of the two joint parts can also be ensured. The universality of the cable-driven joint module is high.

[0051] As Figure 2 shown, the end of the first joint part 100 facing the second joint part 200 is the first joint end 110, and the end of the second joint part 200 facing the first joint part 100 is the second joint end 210. The first joint end 110 and the second joint end 210 can be set as planes. Among them, both ends of the central rod 410 are respectively arranged at the center of the ends of the first joint end 110 and the second joint end 210.

[0052] The two first driving cables 310 of the driving module form a first driving cable pair. Both ends of each first driving cable 310 are respectively arranged at the ends of the first joint part 100 and the second joint part 200, and the two first driving cables 310 are symmetrically distributed with respect to the central rod 410. The two first driving cables 310 and the central rod 410 are in the same plane.

[0053] The two second driving cables 320 of the driving module form a second driving cable pair. Both ends of each second driving cable 320 are respectively arranged at the ends of the first joint part 100 and the second joint part 200, and the two second driving cables 320 are symmetrically distributed with respect to the central rod 410. The two second driving cables 320 and the central rod 410 are in the same plane.

[0054] The line connecting the two connection points of the two first driving ropes 310 and the first joint portion 100 forms a first rotation axis, and the line connecting the two connection points of the two second driving ropes 320 and the first joint portion 100 forms a second rotation axis. The first rotation axis and the second rotation axis are vertically intersecting at the end center of the first joint portion 100. The plane where the two first driving ropes 310 are located and the plane where the two second driving ropes 320 are located are perpendicular and intersect at the central rod 410.

[0055] In this embodiment, the second joint portion 200 is rotatably connected to the first joint portion 100 through a driving module. Among them, the second joint portion 200 is used to rotate along the first rotation axis to achieve the first-degree-of-freedom rotation, and the second joint portion 200 is used to rotate along the second rotation axis to achieve the second-degree-of-freedom rotation.

[0056] In actual execution, the two first driving ropes 310 are symmetrically distributed with respect to the central rod 410. By taking in and releasing the two first driving ropes 310, the second joint portion 200 can be driven to rotate along the second rotation axis to achieve the second-degree-of-freedom rotation; the two second driving ropes 320 are symmetrically distributed with respect to the central rod 410. By taking in and releasing the two second driving ropes 320, the second joint portion 200 can be driven to rotate along the first rotation axis to achieve the first-degree-of-freedom rotation.

[0057] For example, as Figure 2 shown, the two first driving ropes 310 are ae and cg respectively. By taking in the ae rope downward and releasing the cg rope upward, the second joint portion 200 is driven to rotate counterclockwise along the second rotation axis where the hf line is located.

[0058] By releasing the ae rope upward and taking in the cg rope downward, the second joint portion 200 is driven to rotate clockwise along the second rotation axis where the hf line is located, realizing the bidirectional rotation of the cable-driven joint module in the second degree of freedom.

[0059] In this embodiment, the rotation of the second joint portion 200 along the second rotation axis is only driven by the two first driving ropes 310 and has nothing to do with the two second driving ropes 320. Similarly, the rotation of the second joint portion 200 along the first rotation axis is only driven by the two second driving ropes 320 and has nothing to do with the two first driving ropes 310. That is, the rotation of the cable-driven joint module in the two degrees of freedom is decoupled.

[0060] According to the rope-driven joint module provided by the embodiments of the present application, by setting two pairs of driving ropes, two first driving ropes 310 are arranged on both sides of the central rod 410 to form a first rotation axis, and two second driving ropes 320 are arranged on both sides of the central rod 410 to form a second rotation axis. The two rotation axes are perpendicular to each other and intersect at the central rod 410, realizing two-degree-of-freedom rotation. For each degree of freedom, the bidirectional rotation of the degree of freedom is controlled by two ropes, and the two-degree-of-freedom rotation is decoupled, so the flexibility of the joint drive of the rope-driven joint module is high.

[0061] In some embodiments, the drive module further includes a first drive device.

[0062] In this embodiment, the first ends of the two first driving ropes 310 are wound around the output end of the first drive device, and the second ends of the two first driving ropes 310 are connected to the second joint portion 200. The first drive device is arranged on the first joint portion 100.

[0063] The first end of the first driving rope 310 is connected to the output end of the first drive device. When the first drive device works, the first driving rope 310 can be wound around the output end of the first drive device, and the first drive device takes in the first driving rope 310. The first driving rope 310 can also be unwound from the output end of the first drive device, and the first drive device releases the first driving rope 310.

[0064] Taking the first drive device as a motor as an example.

[0065] The first end of the first driving rope 310 is connected to the output shaft of the motor, and the second end of the first driving rope 310 is connected to the second joint portion 200. When the output shaft of the motor rotates in one direction, it takes in the first driving rope 310. When the output shaft of the motor rotates in the other direction, it releases the first driving rope 310.

[0066] For example, as Figure 2 shown, the two first driving ropes 310 are ae and cg respectively. The first drive device takes in the ae rope and releases the cg rope, driving the second joint portion 200 to rotate counterclockwise along the second rotation axis where the hf connection line is located. The first drive device releases the ae rope and takes in the cg rope, driving the second joint portion 200 to rotate clockwise along the second rotation axis where the hf connection line is located.

[0067] It should be noted that the first drive device may include two output ends in different directions. One of the first driving ropes 310 is taken in, and the other first driving rope 310 is released to drive the two first driving ropes 310 to drive the second joint portion 200 to rotate. Among them, the two output ends in different directions may be the output ends of two motors of the first drive device, or may be two output ends output by one motor of the first drive device through a transmission mechanism.

[0068] In some embodiments, the first driving device is configured to drive the second joint portion 200 to rotate along the second rotation axis through two first driving ropes 310, and the length of the second driving rope 320 between the first joint portion 100 and the second joint portion 200 is equal to the length of the central rod 410.

[0069] In this embodiment, the rotation of the second joint portion 200 along the second rotation axis is only achieved by the first driving device driving two first driving ropes 310. When realizing the second-degree-of-freedom rotation, the lengths of the two second driving ropes 320 between the first joint portion 100 and the second joint portion 200 are equal to the length of the central rod 410 and remain unchanged.

[0070] For example, as Figure 2 shown, the two first driving ropes 310 are ae and cg respectively, and the two second driving ropes 320 are bf and dh respectively.

[0071] As Figure 3 shown, the first driving device retracts the ae rope by a length of Δl1 and pays out the cg rope by a length of Δl3 upward, driving the second joint portion 200 to rotate counterclockwise by an angle of θ along the second rotation axis where the hf connection line is located.

[0072] As Figure 4 shown, between the first joint portion 100 and the second joint portion 200, the length of the bf rope is Δl2, the length of the dh rope is Δl4, the lengths of the two second driving ropes 320 are equal to the length of the central rod 410, and remain unchanged during the rotation of the second joint portion 200 along the second rotation axis.

[0073] In some embodiments, the driving module further includes: a second driving device.

[0074] In this embodiment, the first ends of the two second driving ropes 320 are wound around the output end of the second driving device, the second ends of the two second driving ropes 320 are connected to the second joint portion 200, and the second driving device is disposed on the first joint portion 100.

[0075] The first ends of the second driving ropes 320 are connected to the output end of the second driving device. When the second driving device operates, the second driving ropes 320 can be wound around the output end of the second driving device. The second driving device retracts the second driving ropes 320, and the second driving ropes 320 can also be unwound from the output end of the second driving device, and the second driving device pays out the second driving ropes 320.

[0076] Taking the second driving device as a motor as an example.

[0077] The first end of the second drive rope 320 is connected to the output shaft of the motor, and the second end of the second drive rope 320 is connected to the second joint part 200. When the output shaft of the motor rotates in one direction, the second drive rope 320 is retracted. When the output shaft of the motor rotates in the other direction, the second drive rope 320 is released.

[0078] It should be noted that the second drive device may include two output ends in different directions. One of the second drive ropes 320 is retracted, and the other second drive rope 320 is released to drive the two second drive ropes 320 to drive the second joint part 200 to rotate. Among them, the two output ends in different directions may be the output ends of the two motors of the second drive device, or may be the two output ends output by one motor of the second drive device through a transmission mechanism.

[0079] In some embodiments, the second drive device is used to drive the second joint part 200 to rotate along the first rotation axis through two second drive ropes 320, and the length of the first drive rope 310 between the first joint part 100 and the second joint part 200 is equal to the length of the central rod 410.

[0080] In this embodiment, the rotation of the second joint part 200 along the first rotation axis is only achieved by the second drive device driving the two second drive ropes 320. When realizing the first-degree-of-freedom rotation, the lengths of the two first drive ropes 310 between the first joint part 100 and the second joint part 200 are equal to the length of the central rod 410 and remain unchanged.

[0081] In some embodiments, one end of the central rod 410 is hinged to the first joint part 100, and the other end of the central rod 410 is fixedly connected to the second joint part 200.

[0082] In this embodiment, one end of the central rod 410 is rotatably connected to the first joint part 100, the other end of the central rod 410 is fixedly connected to the second joint part 200, the central rod 410 is supported between the first joint part 100 and the second joint part 200, and the second joint part 200 rotates relative to the first joint part 100 through the hinge structure of the central rod 410.

[0083] It can be understood that the rotation angle range of the second joint part 200 relative to the first joint part 100 is determined based on the rotation range of the hinge of one end of the central rod 410 with the first joint part 100.

[0084] In some embodiments, a spherical hinge structure 411 is provided at one end of the central rod 410, and one end of the central rod 410 is hinged to the first joint part 100 through the spherical hinge structure 411.

[0085] Such as Figure 2As shown, one end of the central rod 410 is provided with a spherical hinge structure 411, and the spherical hinge structure 411 is hinged to the center of the end of the first joint end 110. The other end of the central rod 410 is fixedly connected to the center of the end of the second joint end 210.

[0086] It can be understood that the spherical hinge structure 411 can ensure that the second joint part 200 rotates more smoothly relative to the first joint part 100 and has a larger rotation range.

[0087] The embodiment of the present application also provides a robotic arm, including at least one cable-driven joint module as described above.

[0088] Among them, the cable-driven joint module can achieve two-degree-of-freedom rotation, and the two-degree-of-freedom rotations are decoupled. The robotic arm composed of cable-driven joint modules can effectively resist external disturbances, and the ropes used for driving have the characteristics of light weight, high flexibility, and convenient long-distance power transmission.

[0089] According to the robotic arm provided by the embodiment of the present application, the cable-driven joint module realizes two-degree-of-freedom rotation by arranging two pairs of driving rope pairs. Two first driving ropes 310 are arranged on both sides of the central rod 410 to form a first rotation axis, and two second driving ropes 320 are arranged on both sides of the central rod 410 to form a second rotation axis. The two rotation axes are perpendicular to each other and intersect at the central rod 410. For each degree of freedom, the two-way rotation of the degree of freedom is controlled by two ropes, and the two-degree-of-freedom rotations are decoupled, and the flexibility of the joint drive of the cable-driven joint module is high.

[0090] The embodiment of the present application also provides a robot, including at least one robotic arm as described above.

[0091] Among them, the cable-driven joint module of the robotic arm can achieve two-degree-of-freedom rotation, and the two-degree-of-freedom rotations are decoupled. The above-mentioned robotic arm can be used in parts such as the neck, wrist, tail, and operating structure of the robot.

[0092] According to the robot provided by the embodiment of the present application, the cable-driven joint module realizes two-degree-of-freedom rotation by arranging two pairs of driving rope pairs. Two first driving ropes 310 are arranged on both sides of the central rod 410 to form a first rotation axis, and two second driving ropes 320 are arranged on both sides of the central rod 410 to form a second rotation axis. The two rotation axes are perpendicular to each other and intersect at the central rod 410. For each degree of freedom, the two-way rotation of the degree of freedom is controlled by two ropes, and the two-degree-of-freedom rotations are decoupled, and the flexibility of the joint drive of the cable-driven joint module is high.

[0093] Currently, for the two-way rotation of one degree of freedom of the cable-driven joint, two motors are mostly used to drive two driving ropes respectively.

[0094] In related technologies, there are mainly two solutions for using one motor to drive two drive ropes: the first is to design the actuators at the contact parts of two joints as circular shapes, so that the rope lengths of the two drive ropes change equally, and then drive them with one motor. However, such circular actuators do not have universality; the second is to install a passive recovery device such as a torsion spring. One direction of the drive rope is driven by the motor, and the other direction of the drive rope is recovered by the passive recovery device. The drive control accuracy is low and bidirectional drive cannot be achieved.

[0095] The embodiment of the present application also provides a cable-driven joint module, which can realize the bidirectional drive of the cable-driven rotary joint through a single motor, has high control accuracy, does not require additional setting of other structures, and has high universality.

[0096] As Figure 5 shown, the cable-driven joint module includes a first joint part 100, a second joint part 200 and a drive module. The second joint part 200 is rotatably connected to the first joint part 100 through the drive module.

[0097] Among them, the drive module includes a drive motor 510, a transmission mechanism and a pair of drive ropes. The pair of drive ropes includes two drive ropes 300. The transmission mechanism includes a rotating wheel 521 and two driven parts 523. The rotating wheel 521 is connected to the output end of the drive motor 510. One cam 522 is arranged on each side of the rotating wheel 521. The cam 522 contacts the driven part 523, and the rotation of the cam 522 causes the driven part 523 to perform a reciprocating motion.

[0098] It should be noted that the cam 522 is a component with a curved profile and performs a rotary motion; the driven part 523 contacts the profile of the cam 522. The driven part 523 is a component that transmits power to realize the winding and unwinding of the drive rope 300. The cam 522 rotates together with the rotating wheel 521, and the driven part 523 performs a reciprocating motion within a certain range.

[0099] The rotating wheel 521 is connected to the output end of the drive motor 510. One cam 522 is arranged on each side of the rotating wheel 521. Driven by the output end of the drive motor 510, the two cams 522 on the rotating wheel 521 perform a rotary motion, and then the winding and unwinding of the drive rope 300 are realized through the power transmission of the two driven parts 523.

[0100] In this embodiment, one end of the drive rope 300 is connected to the second joint part 200, and the other end of the drive rope 300 passes through the through hole on the end face of the first joint part 100 and is connected to the cam 522. The drive rope 300 passes through the part where the cam 522 and the driven part 523 contact, and the drive rope 300 is wound around the cam 522.

[0101] It can be understood that when the cam 522 rotates, the driving rope 300 is pressed by the follower 523 to wind around or unwind from the cam 522. The up and down movement of the follower 523 is restricted by the contour of the cam 522. The follower 523 can ensure that the driving rope 300 can completely wind around the cam 522 and leave or enter the cam 522 from the specified position (the contact part between the cam 522 and the follower 523).

[0102] Among them, the driving motor 510 is used to drive the rotating wheel 521 to rotate, drive one cam 522 to suck in one driving rope 300 in the driving rope pair, and drive the other cam 522 to release the other driving rope 300 in the driving rope pair, so as to realize the rotational freedom of the second joint part 200 along the direction of the line connecting the two connection points of the two driving ropes 300 and the first joint part 100.

[0103] For example, for the end of the first joint part 100, the two connection points of the two driving ropes 300 and the first joint part 100 of the second joint part 200 are distributed on the left and right sides of the end.

[0104] The driving motor 510 drives the rotating wheel 521 to rotate, drives the left cam 522 to rotate, sucks in the left driving rope 300, and at the same time drives the right cam 522 to rotate and release the right driving rope 300. The second joint part 200 rotates from right to left.

[0105] It can be understood that the contour of the cam 522 is different from the circular contour. By setting two independent cams 522 in the transmission mechanism, the length changes of the two driving ropes 300 during the joint rotation can be made unequal. Using one driving motor 510 can drive the two driving ropes 300 to realize the two-way rotation of a certain degree of freedom.

[0106] It should be noted that the curvature of the cam 522 of the transmission mechanism is positive, which can ensure that the stress magnitude of the driving rope 300 remains unchanged during the rotation process and ensure the effectiveness of the joint movement.

[0107] In some embodiments, as Figure 6 shown, the cable-driven joint module includes a first driving rope pair composed of two first driving ropes 310, a second driving rope pair composed of two second driving ropes 320, and a central rod 410.

[0108] The connection line of the two connection points of the two first driving ropes 310 and the first joint part 100 forms a first rotation axis, and the connection line of the two connection points of the two second driving ropes 320 and the first joint part 100 forms a second rotation axis. The first rotation axis and the second rotation axis are perpendicularly intersected at the end center of the first joint part 100. The second joint part 200 can rotate along the first rotation axis to achieve the first-degree-of-freedom rotation, and rotate along the second rotation axis to achieve the second-degree-of-freedom rotation.

[0109] In this embodiment, a set of driving motors 510 and transmission mechanisms can be configured for the first driving rope pair to achieve the second-degree-of-freedom rotation, and a set of driving motors 510 and transmission mechanisms can be configured for the second driving rope pair to achieve the first-degree-of-freedom rotation.

[0110] According to the rope-driven joint module provided by the embodiment of the present application, by setting a transmission mechanism with two independent cams 522, the driving ropes 300 on both sides are respectively sucked in and released. A single driving motor 510 can achieve the bidirectional driving of the rope-driven rotary joint, with high control precision, without the need to additionally set other structures, and has high universality.

[0111] In some embodiments, the end of the first joint part 100 facing the second joint part 200 is a plane, and the end of the second joint part 200 facing the first joint part 100 is a plane.

[0112] It can be understood that the two independent cams 522 on the transmission mechanism can make the lengths of the two driving ropes 300 change unequally during the rotation of the joint. The opposite end faces of the two joint parts do not need to be set as arc surfaces convenient for pivoting, that is, the opposite end faces of the two joint parts do not need to be designed as circular actuators.

[0113] In this embodiment, setting the end of the first joint part 100 facing the second joint part 200 as a plane and the end of the second joint part 200 facing the first joint part 100 as a plane can improve the universality of the rope-driven joint module.

[0114] In some embodiments, the transmission mechanism further includes two tension pre-tightening devices 530 corresponding to the two driving ropes 300 one by one. The tension pre-tightening devices 530 are located between the driven member 523 and the end face of the first joint part 100, and the tension pre-tightening devices 530 are in contact with the driving ropes 300.

[0115] In this embodiment, the tension pre-tightening devices 530 and the transmission mechanism can be arranged in the internal space of the first joint part 100. One end of the driving rope 300 is connected to the second joint part 200, and the other end of the driving rope 300 passes through the through hole on the end face of the first joint part 100, enters the internal space of the first joint part 100, first contacts with the tension pre-tightening device 530, then winds around the driven member 523, and finally is connected to the cam 522.

[0116] It should be noted that one end of the driving rope 300 is fixedly connected to the second joint part 200, and the other end of the driving rope 300 is fixedly connected to the cam 522. During the rotation of the cam 522, the driving rope 300 can be wound or unwound on the cam 522.

[0117] In this embodiment, a tension preloading device 530 is provided between the follower 523 and the end face of the first joint part 100. By applying a force to the driving rope 300 through the tension preloading device 530, the driving rope 300 is kept under a certain stress to ensure the effectiveness of the joint movement.

[0118] In some embodiments, the cable-driven joint module may further include two tension sensors corresponding to the two driving ropes 300 one by one. The tension sensors are located between the tension preloading device 530 and the end face of the first joint part 100, and the tension sensors are in contact with the driving ropes 300. The tension sensors are used to detect the tension force of the driving ropes 300.

[0119] In this embodiment, each driving rope 300 is provided with a corresponding tension sensor. The tension sensors are arranged in the space between the tension preloading device 530 and the end face of the first joint part 100. According to the tension force of the driving rope 300 detected by the tension sensors, the magnitude of the force applied by the tension preloading device 530 to the driving rope 300 can be adjusted.

[0120] In some embodiments, the displacement range of the reciprocating movement of the follower 523 is determined based on the contour parameters of the cam 522.

[0121] In this embodiment, the driving rope 300 is connected to the second joint part 200. The other end of the driving rope 300 first passes through the through hole on the end face of the first joint part 100, and then passes through the contact part between the cam 522 and the follower 523 and is connected to the cam 522. When the cam 522 rotates, the driving rope 300 is pressed by the follower 523 and wound or released from the cam 522. The up and down movements of the follower 523 are restricted by the contour of the cam 522.

[0122] In actual implementation, the rotation trajectory of the cam 522 can be calculated according to the contour parameters of the cam 522. According to the rotation trajectory of the cam 522, the up and down movement distances of the follower 523 can be calculated to obtain the displacement range of the reciprocating movement of the follower 523.

[0123] In some embodiments, the driving module may further include a limiting mechanism.

[0124] In this embodiment, the limiting mechanism is arranged at the connection between the rotating wheel 521 and the output end of the driving motor 510. The limiting mechanism is used to limit the position of the rotating wheel 521 so that the zero position of the cam 522 is aligned with the zero position of the second joint part 200.

[0125] It should be noted that the contour of the cam 522 is different from the circular contour. The cam 522 starts from different positions, and the contour changes when rotating the same angle are different, that is, the lengths of the driving rope 300 absorbed or released by the cam 522 and the follower 523 are different.

[0126] In this embodiment, the position of the rotating wheel 521 is limited by the limiting mechanism so that the zero position of the cam 522 is aligned with the zero position of the second joint part 200, and the corresponding relationship between the rotation angle of the rotating wheel 521 and the length change of the driving rope 300 on the cam 522 is determined, realizing precise control of the rotation angle of the second joint part 200.

[0127] In actual implementation, the limiting mechanism may include a limiting pin and a limiting hole provided on the rotating wheel 521. When adjusting the zero positions of the cam 522 and the second joint part 200, the limiting pin is inserted into the limiting hole.

[0128] Wherein, the zero position of the second joint part 200 may be the position where the rotation angle of the second joint part 200 is 0, and the zero position of the cam 522 may be the position of the connection point between the cam 522 and the driving rope 300.

[0129] In some embodiments, the distance between the center point of rotation of the second joint part 200 and the connection point between the driving rope 300 and the first joint part 100 is the first distance;

[0130] When the second joint part 200 is in the zero position, the length of the driving rope 300 exposed from the end 210 of the second joint part is the second distance;

[0131] Wherein, the ratio of the first distance to the second distance is 1 / 3 - 2 / 3.

[0132] It should be noted that the second joint part 200 rotates in the direction of freedom along the connection line of the two connection points between the two driving ropes 300 and the first joint part 100. The center point of rotation of the second joint part 200 is the midpoint of the two connection points between the two driving ropes 300 and the first joint part 100, that is, the first distance is half of the distance of the connection line of the two connection points.

[0133] The zero position of the second joint part 200 can be the position where the rotation angle of the second joint part 200 is 0. When the second joint part 200 is in the zero position, the length of the driving rope 300 exposed from the end 210 of the second joint part can be equal to the distance from the connection point of the driving rope 300 and the first joint part 100 to the connection point of the driving rope 300 and the second joint part 200.

[0134] In some embodiments, such as Figure 6 As shown, the cable-driven joint module includes a central rod 410. When the second joint part 200 is in the zero position, the length of the driving rope 300 exposed from the end 210 of the second joint part can be equal to the length of the central rod 410.

[0135] It should be noted that by setting the ratio of the first distance to the second distance to 1 / 3 - 2 / 3 and adjusting the sizes of the first joint part 100, the second joint part 200, and the driving rope 300, the control accuracy of the rotation of the second joint part 200 relative to the first joint part 100 can be ensured.

[0136] For example, as Figure 7 shown, the first distance w = 18 mm, the second distance is h = 40 mm, and the ratio of the first distance to the second distance is approximately 1 / 2, ensuring the control accuracy of the rotation of the second joint part 200 relative to the first joint part 100.

[0137] In some embodiments, the cable-driven joint module further includes a first encoder and a second encoder.

[0138] Among them, the first encoder is disposed on one of the second joint part 200 or the first joint part 100, and the first encoder is used to detect the joint rotation angle of the second joint part 200 relative to the first joint part 100; the second encoder is disposed on the driving motor 510, and the second encoder is used to detect the motor rotation angle of the rotating wheel 521. An embodiment of the present application further provides a robot including at least one cable-driven joint module as described above.

[0139] Among them, the cable-driven joint module can achieve bidirectional rotation of the joint driven by a single driving motor 510 by setting a transmission mechanism with two independent cams 522.

[0140] In actual implementation, the cable-driven joint module can be used to construct the mechanical arms of the neck, wrist, tail, operating structure, etc. of the robot, so that the mechanical arm can effectively resist external disturbances. The driving ropes used have the characteristics of light weight, high flexibility, and convenient long-power transmission.

[0141] According to the robot provided by the embodiment of the present application, the rope-driven joint module respectively sucks in and releases the driving ropes 300 on both sides by setting a transmission mechanism with two independent cams 522. A single driving motor 510 can achieve the bidirectional driving of the rope-driven rotary joint, with high control precision, without the need to additionally set other structures, and has high universality.

[0142] According to the robot provided by the embodiment of the present application, the rope-driven joint module respectively sucks in and releases the driving ropes 300 on both sides by setting a transmission mechanism with two independent cams 522. A single driving motor 510 can achieve the bidirectional driving of the rope-driven rotary joint, with high control precision, without the need to additionally set other structures, and has high universality.

[0143] The embodiment of the present application also provides a method for designing the cam profile of the rope-driven joint module. The designed cam 522 can achieve the bidirectional driving of the rope-driven rotary joint through a single motor.

[0144] As Figure 5 shown, the rope-driven joint module includes a first joint part 100, a second joint part 200 and a driving module. The second joint part 200 is rotatably connected to the first joint part 100 through the driving module.

[0145] The driving module includes a driving motor 510, a rotating wheel 521 and a pair of driving ropes. The pair of driving ropes includes two driving ropes 300. The rotating wheel 521 is connected to the output end of the driving motor 510, and one cam 522 is provided on each side of the rotating wheel 521.

[0146] One end of the driving rope 300 is connected to the second joint part 200, and the other end of the driving rope 300 passes through the through hole on the end face of the first joint part 100 and is connected to the cam 522.

[0147] The driving motor 510 is used to drive the rotating wheel 521 to rotate, drive one cam 522 to suck in one driving rope 300 in the pair of driving ropes, and drive the other cam 522 to release the other driving rope 300 in the pair of driving ropes, so as to realize the rotational freedom of the second joint part 200 along the direction of the line connecting the two connection points of the two driving ropes 300 and the first joint part 100. Among them, the method for designing the cam profile of the rope-driven joint module can be applied to the terminal, and can be specifically executed by the hardware or software in the terminal.

[0148] The cam profile design method of the cable-driven joint module provided by the embodiment of the present application. The execution subject of the cam profile design method of the cable-driven joint module can be an electronic device or a functional module or functional entity in the electronic device that can implement the cam profile design method of the cable-driven joint module. The electronic devices mentioned in the embodiments of the present application include, but are not limited to, mobile phones, tablet computers, computers, etc. Hereinafter, taking the electronic device as the execution subject as an example, the cam profile design method of the cable-driven joint module provided by the embodiment of the present application will be described.

[0149] As Figure 9 shown, the cam profile design method of the cable-driven joint module includes: steps 910 to 970.

[0150] Step 910, obtain the length-angle correspondence relationship between the length of the drive cable 300 between the end faces of the first joint part 100 and the second joint part 200 and the joint rotation angle of the second joint part 200 rotating relative to the first joint part 100.

[0151] It can be understood that the length of the drive cable 300 between the end faces of the first joint part 100 and the second joint part 200 changes as the second joint part 200 is in different rotation positions (corresponding to different joint rotation angles). According to the angle range of the second joint part 200 rotating relative to the first joint part 100, the length-angle correspondence relationship can be obtained through geometric conversion.

[0152] For example, as Figure 7 shown, between the end faces of the first joint part 100 and the second joint part 200, the length of the left drive cable 300 is l L , and the length of the right drive cable 300 is l R .

[0153] When the second joint part 200 rotates leftward by θ from the vertical position, through geometric conversion, the relational expression between l L and θ is as follows:

[0154]

[0155] Among them, h is the distance between the first joint part 100 and the second joint part 200, and this distance can be equal to the length of the central rod 410; w is the radius of the first joint part 100, and this radius can be equal to the distance between the center point of rotation of the second joint part 200 and the connection point of the drive cable 300 and the first joint part 100; a is the radius of the second joint part 200, and the value of a can be equal to w; θ is the joint rotation angle of the second joint part 200 rotating, and α is the deflection angle from the end center of the first joint part 100 to the connection point of the drive cable 300 on the second joint part 200.

[0156] Step 920: Based on the length-angle correspondence relationship, according to the characteristic that the length of the rope released and absorbed by the cam 522 corresponding to a certain rotation angle of a motor when the rotating wheel 521 rotates is equal to the length of the rope released and absorbed by the end face of the first joint part 100 corresponding to a certain joint rotation angle when the second joint part 200 rotates, establish a first relationship model regarding the length of the driving rope 300, the contour length and the contour radius of the cam 522.

[0157] It should be noted that to ensure that the joint does not fail during the rotation process, the length of the rope released by one cam 522 of the transmission mechanism and the length of the rope absorbed by the other cam 522 should be equal to the length of the rope released and absorbed by the end face of the first joint part 100 when the second joint part 200 rotates, respectively.

[0158] For example, as Figure 7 shown, when the rotating wheel 521 rotates counterclockwise by a small angle dq, the cam 522 corresponding to the driving rope on the left side absorbs the driving rope 300 with a length of dl L The driving rope 300 with a length of dl is absorbed downward by the driving rope 300 on the left side of the end face of the first joint part 100; the cam 522 corresponding to the driving rope on the right side absorbs the driving rope 300 with a length of dl L The driving rope 300 with a length of dl is absorbed downward by the driving rope 300 on the right side of the end face of the first joint part 100. It can be understood that the contour of the cam 522 on one side can be solved separately according to the length-angle correspondence relationship corresponding to this side. R The driving rope 300 with a length of dl is absorbed downward by the driving rope 300 on the right side of the end face of the first joint part 100. It can be understood that the contour of the cam 522 on one side can be solved separately according to the length-angle correspondence relationship corresponding to this side. R The driving rope 300 with a length of dl is absorbed downward by the driving rope 300 on the right side of the end face of the first joint part 100. It can be understood that the contour of the cam 522 on one side can be solved separately according to the length-angle correspondence relationship corresponding to this side.

[0159] In this embodiment, according to the length-angle correspondence relationship, establish a first relationship model for the length of the driving rope 300 on one side, the contour length and the contour radius of the cam 522. Among them, the length of the driving rope 300 inhaled or released by the rotation of the cam 522 can be calculated according to the change of the contour length and the contour radius of the rotation of the cam 522.

[0160] In actual execution, as Figure 5 shown, the driving module further includes two follower parts 523. One cam 522 is provided on each side of the rotating wheel 521. The cam 522 contacts the follower part 523. The follower part 523 is a component that transmits power to realize the winding and unwinding of the driving rope 300. The rotation of the cam 522 causes the follower part 523 to perform a reciprocating motion.

[0161] When the cam 522 rotates, the driving rope 300 is pressed by the follower 523 to wind around or unwind from the cam 522. The up-and-down movement of the follower 523 is restricted by the contour of the cam 522. The follower 523 can ensure that the driving rope 300 can completely wind around the cam 522 and leave or enter the cam 522 from a specified position (the contact part between the cam 522 and the follower 523).

[0162] In some embodiments, as Figure 8 shown, the change in the contour radius of the cam 522 can be characterized by the small displacement change of the contact point 524 where the follower 523 contacts the cam 522 during the rotation of the cam 522. That is, by using a differential equation to describe the first relationship model of the length of the driving rope 300, the contour length of the cam 522, and the contour radius, the following first differential equation corresponding to the first relationship model can be obtained:

[0163] dl L (θ)+ds(q)+(-dr(q))=0

[0164] Wherein, dl L is the differential of the length of the driving rope 300, θ is the joint rotation angle of the second joint part 200 during rotation, ds is the differential of the contour length of the cam 522, dr is the differential of the contour radius of the cam 522, and q is the motor rotation angle of the rotating wheel 521 (i.e., the rotation angle of the cam 522).

[0165] In some embodiments, the contour length of the cam 522 is calculated based on the contour radius of the cam 522 and the motor rotation angle of the rotating wheel 521 by the Pythagorean theorem.

[0166] In this embodiment, according to the constant stress of the driving rope 300, the change in the contour length of the cam 522 is equal to the change in the length of the driving rope 300 on the cam 522. According to the Pythagorean theorem, the following calculation formula for the differential of the contour length of the cam 522 can be obtained:

[0167]

[0168] Wherein, ds is the differential of the contour length of the cam 522, dr is the differential of the contour radius of the cam 522, and q is the motor rotation angle.

[0169] Step 930: Establish a second relationship model according to the linear correlation characteristics of the motor rotation angle of the rotating wheel 521 and the joint rotation angle of the second joint part 200.

[0170] In this embodiment, according to the linear correlation between the motor rotation angle of the rotating wheel 521 and the joint rotation angle of the second joint portion 200, a second relationship model between the motor rotation angle and the joint rotation angle is established.

[0171] In some embodiments, a differential equation can be used to describe the second relationship model between the motor rotation angle and the joint rotation angle. For example, the second differential equation corresponding to the second relationship model is dq = Kr dθ, where dq is the differential value of the motor rotation angle, dθ is the differential value of the joint rotation angle, and Kr is the kinematic coefficient linearly related to the motor rotation angle and the joint rotation angle.

[0172] It can be understood that when the motor rotation angle and the joint rotation angle are linearly related, the control accuracy of joint rotation can be improved.

[0173] Step 940: Based on the first relationship model and the second relationship model, establish a target relationship model regarding the length of the drive cable 300, the motor rotation angle of the rotating wheel 521, and the profile radius of the cam 522.

[0174] In this step, according to the first relationship model representing the relationship between the length of the drive cable 300, the profile length of the cam 522, and the change in the profile radius, and the second relationship model representing the linear relationship between the motor rotation angle and the joint rotation angle, by substituting and eliminating variables such as the joint rotation angle and the profile length, a target relationship model regarding the length of the drive cable 300, the motor rotation angle of the rotating wheel 521, and the profile radius of the cam 522 is obtained.

[0175] For example, for the left drive cable 300, the first differential equation corresponding to the first relationship model is dl L (θ) + ds(q) + (-dr(q)) = 0, where The second differential equation corresponding to the second relationship model is dq = Kr dθ.

[0176] The target differential equation corresponding to the target relationship model calculated according to the first relationship model and the second relationship model is as follows:

[0177]

[0178] where r is the profile radius of the cam 522, q is the motor rotation angle, Kr is the kinematic coefficient linearly related to the motor rotation angle and the joint rotation angle, and dl L is the differential of the length of the drive cable 300.

[0179] Step 950: According to the characteristic that the curvature of the cam 522 is positive, determine the first constraint condition regarding the motor rotation angle of the rotating wheel 521 and the profile radius of the cam 522.

[0180] In this embodiment, according to the positive curvature of the cam 522, the first constraint condition of the motor rotation angle and the contour radius of the cam 522 is established. The positive curvature of the cam 522 of the transmission mechanism can ensure that the above kinematic equation is satisfied during the rotation process. That is, the positive curvature of the cam 522 is the premise to ensure the effectiveness of the joint movement.

[0181] In the process of solving the contour radius in the target relationship model, by being constrained by the first constraint condition, it can effectively prevent the concave section from appearing in the design of the cam 522 and avoid changing the stress magnitude of the driving rope 300.

[0182] According to the positive curvature of the cam 522, the determined first constraint condition can be as follows:

[0183]

[0184] Wherein, r is the contour radius of the cam 522, and q is the motor rotation angle.

[0185] Step 960: According to that the change of the contour radius of the cam 522 relative to the motor rotation angle of the rotating wheel 521 is less than or equal to the square of the target coefficient and much less than 1, perform an approximation process on the target relationship model.

[0186] It should be noted that when the motor rotation angle is small, the change of the contour radius of the cam 522 is also small, and the change of the contour radius of the cam 522 is even smaller relative to the change of the motor rotation angle.

[0187] The change of the contour radius of the cam 522 relative to the change of the motor rotation angle can be expressed as The magnitude of can be characterized by the target coefficient, The square of is less than or equal to the square of the target coefficient, and the square of the target coefficient is much less than 1, as shown in the following formula:

[0188]

[0189] Wherein, ε is the target coefficient.

[0190] According to the inequality of the target coefficient, the approximation process can be performed on the target relationship model to obtain the target differential equation corresponding to the following target relationship model:

[0191] Step 970: According to the boundary conditions and the first constraint condition of the contour radius of the cam 522 and the motor rotation angle of the rotating wheel 521, solve the approximately processed target relationship model to obtain the solution set of the contour radius of the cam 522.

[0192] In this embodiment, for the target relationship model after approximation processing, there is an analytical solution for the contour radius regarding the boundary conditions. Within the angular range of the motor rotation angle, the analytical solutions at multiple sampling points can be solved to obtain the solution set of the contour radius of the cam 522, which represents the contour of the cam 522.

[0193] In actual implementation, for the contour of the cam 522, the analytical solution is continuous and smooth, and the continuous solution can be discretized to facilitate the solution calculation of the contour radius.

[0194] For example, the boundary condition for the contour radius of the cam 522 and the motor rotation angle of the rotating wheel 521 is r(q0) = r0.

[0195] Let the function The target differential equation corresponding to the target relationship model after approximation processing is The corresponding analytical solution for the boundary condition r(q0) = r0 is: where g(τ) = -f(τ)e -τ .

[0196] where τ represents the integration variable,

[0197] In this embodiment, the angular range of the motor rotation angle is defined as q ∈ [0, q M , and N + 1 sampling points are collected within the domain to represent the contour of the cam 522.

[0198] It should be noted that the boundary conditions can be adjusted according to the cam 522 to be designed. After setting the boundary conditions, on the premise that the change in the contour radius of the cam 522 with respect to the motor rotation angle of the rotating wheel 521 is less than or equal to the square of the target coefficient and much less than 1 and the first constraint condition, different objective functions (for example, the minimum contour size of the cam 522) are set, and the target relationship model is solved to obtain the solution set of the contour radius of the cam 522.

[0199] According to the cam contour design method of the cable-driven joint module provided by the embodiments of the present application, by using system parameters such as the contour radius and contour length of the cam 522 and the kinematic relationship between the cam 522 driving the driving cable 300 to inhale and exhale, a target relationship model regarding the contour radius is established. Under the constraint of positive curvature, the track contour is jointly solved, and the designed cam 522 can achieve the bidirectional rotation of a single rotating wheel 521 to drive the rotating joint, ensuring the control accuracy and motion stability of the cable-driven joint module.

[0200] In some embodiments, according to the boundary conditions and the first constraint condition of the contour radius of the cam 522 and the motor rotation angle of the rotating wheel 521, solving the target relationship model after approximation processing may include:

[0201] Approximate the first constraint condition based on the fact that the change in the contour radius of the cam 522 with respect to the motor rotation angle of the rotating wheel 521 is less than or equal to the square of the target coefficient and much less than 1.

[0202] Under the condition that the first constraint condition after approximation is satisfied and the change in the contour radius of the cam 522 with respect to the motor rotation angle of the rotating wheel 521 is less than or equal to the square of the target coefficient and much less than 1, determine the boundary conditions and solve the approximated target relationship model.

[0203] In this embodiment, approximate the first constraint condition regarding the contour radius of the cam 522 and the motor rotation angle based on the condition that the change in the contour radius of the cam 522 with respect to the change in the motor rotation angle is small.

[0204] For example, based on the positive curvature of the cam 522, the first constraint condition is Based on Approximate the first constraint condition to obtain The inequality of.

[0205] Set the boundary conditions according to the cam 522 to be designed. Under the condition that the first constraint condition after approximation is satisfied and the change in the contour radius of the cam 522 with respect to the motor rotation angle of the rotating wheel 521 is less than or equal to the square of the target coefficient and much less than 1, solve the approximated target relationship model to obtain the solution set of the contour radius of the cam 522.

[0206] In some embodiments, determining the boundary conditions may include:

[0207] Optimize the target coefficient to determine the optimal target coefficient, and the approximation error between the target relationship model and the first constraint condition corresponding to the optimal target coefficient is the smallest;

[0208] Based on the optimal target coefficient, determine the boundary conditions.

[0209] It can be understood that the approximation processing of the target relationship model and the first constraint condition is carried out under the condition that the change in the contour radius of the cam 522 with respect to the change in the motor rotation angle is small, and the error generated by the approximation processing can be limited by the target coefficient.

[0210] For the first constraint condition after approximation At the sampling point k, there is N. Based on the fact that the change in the contour radius of the cam 522 with respect to the change in the motor rotation angle is small, it can be obtained that That is, the boundary condition r0 is linearly related to the target coefficient ε.

[0211] In this embodiment, the error generated by the approximation process can be characterized as de(q) and can be restricted by the target coefficient.

[0212] In actual execution, the target coefficient can be optimized to limit the error caused by the approximation process, find the optimal target coefficient and the corresponding boundary conditions through optimization, and then solve the target relationship model after approximation to obtain the contour radius solution of the cam 522.

[0213] In some embodiments, optimizing the target coefficient to determine the optimal target coefficient may include:

[0214] Searching for the optimal target coefficient by the bisection method.

[0215] In this embodiment, the bisection method is used to search for the feasible and minimum optimal target coefficient that satisfies the condition that the change in the contour radius of the cam 522 is relatively small with respect to the change in the motor rotation angle.

[0216] A specific embodiment is introduced below.

[0217] As Figure 7 shown, for the cable-driven joint module, h = 40 mm, a = w = 18 mm.

[0218] As Figure 10 shown, four target coefficients ε, namely 0.6, 0.3, 0.15, and 0.21, are selected by the bisection method. Each curve represents the contour of the cam 522 with different target coefficients ε and different boundary conditions r0. When the curve representing the contour of the cam 522 is within the infeasible shaded range, it means that the boundary condition r0 and the target coefficient ε are infeasible.

[0219] For example, when the target coefficient ε = 0.3 and the boundary condition r0 = 5.7 mm, and the curve representing the contour of the cam 522 is within the shaded range, this boundary condition r0 and the target coefficient ε are infeasible.

[0220] In this embodiment, the bisection method searches to obtain the optimal target coefficient ε = 0.21, corresponding to r0 = 5.8 mm. The bold curve in (d) represents the contour of the cam 522. Substituting the optimal target coefficient ε = 0.21 and the boundary condition r0 = 5.8 mm into the analytical solution of the target relationship model, the contour radius solution of the cam 522 is obtained.

[0221] The embodiment of the present application also provides a cable-driven joint module.

[0222] As Figure 5 shown, the cable-driven joint module includes: a first joint portion 100, a second joint portion 200, and a drive module.

[0223] The driving module includes a driving motor 510, a rotating wheel 521 and a pair of driving ropes. The pair of driving ropes includes two driving ropes 300. The rotating wheel 521 is connected to the output end of the driving motor 510. A cam 522 is provided on each side of the rotating wheel 521. One end of the driving rope 300 is connected to the second joint part 200, and the other end of the driving rope 300 passes through the through hole on the end face of the first joint part 100 and is connected to the cam 522. The driving motor 510 is used to drive the rotating wheel 521 to rotate, drive one cam 522 to suck in one driving rope 300 in the pair of driving ropes, and drive the other cam 522 to release the other driving rope 300 in the pair of driving ropes, so that the second joint part 200 rotates in the degree of freedom direction along the connection line of the two connection points of the two driving ropes 300 and the first joint part 100.

[0224] In this embodiment, the contour of the cam 522 is determined based on the cam contour design method of the above-mentioned cable-driven joint module.

[0225] In actual implementation, as Figure 5 shown, the driving module may further include two follower members 523. A cam 522 is provided on each side of the rotating wheel 521. The cam 522 contacts the follower member 523. The follower member 523 is a component that transmits power to realize the winding and unwinding of the driving rope 300. The rotation of the cam 522 causes the follower member 523 to perform a reciprocating motion.

[0226] When the cam 522 rotates, the driving rope 300 is pressed by the follower member 523 to wind around the cam 522 or be released from the cam 522. The upward and downward movements of the follower member 523 are restricted by the contour of the cam 522. The follower member 523 can ensure that the driving rope 300 can completely wind around the cam 522 and leave or enter the cam 522 from a specified position (the contact part of the cam 522 and the follower member 523).

[0227] According to the cable-driven joint module provided by the embodiment of the present application, by the system parameters such as the contour radius and contour length of the cam 522 and the kinematic relationship between the cam 522 driving the driving rope 300 to suck in and release, a target relationship model about the contour radius is established, and the track contour is jointly solved under the constraint of positive curvature, and the designed cam 522 is obtained. The cable-driven joint module composed of the cam 522 can realize the bidirectional rotation of a single rotating wheel 521 driving a rotary joint, ensuring the control accuracy and motion stability of the cable-driven joint module.

[0228] The embodiment of the present application further provides a robot, including: at least one cable-driven joint module as described above, and the contour of the cam 522 of the cable-driven joint module is determined based on the cam contour design method of the above-mentioned cable-driven joint module.

[0229] The cam profile design method of the cable-driven joint module provided by the embodiment of the present application may have the cam profile design device of the cable-driven joint module as the execution subject.

[0230] The embodiment of the present application also provides a cam profile design device of a cable-driven joint module.

[0231] As Figure 11 shown, the cam profile design device of the cable-driven joint module includes:

[0232] An acquisition module 1110, configured to acquire the length-angle correspondence relationship between the length of the drive cable 300 between the end faces of the first joint part 100 and the second joint part 200 and the joint rotation angle of the second joint part 200 rotating relative to the first joint part 100;

[0233] A first processing module 1120, configured to establish a first relationship model regarding the length of the drive cable 300, the profile length and profile radius of the cam 522 based on the length-angle correspondence relationship according to the characteristic that the length of the cable released and absorbed by the cam 522 corresponding to the rotation angle of the rotation wheel 521 rotating motor is equal to the length of the cable released and absorbed by the end face of the first joint part 100 corresponding to the joint rotation angle of the second joint part 200;

[0234] A second processing module 1130, configured to establish a second relationship model according to the linear correlation characteristic between the motor rotation angle of the rotation wheel 521 and the joint rotation angle of the second joint part 200;

[0235] A third processing module 1140, configured to establish a target relationship model regarding the length of the drive cable 300, the motor rotation angle of the rotation wheel 521 and the profile radius of the cam 522 based on the first relationship model and the second relationship model;

[0236] A fourth processing module 1150, configured to determine a first constraint condition regarding the motor rotation angle of the rotation wheel 521 and the profile radius of the cam 522 according to the characteristic that the curvature of the cam 522 is positive;

[0237] A fifth processing module 1160, configured to perform an approximation process on the target relationship model according to the change of the profile radius of the cam 522 relative to the motor rotation angle of the rotation wheel 521 being less than or equal to the square of the target coefficient and much less than 1;

[0238] A sixth processing module 1170, configured to solve the approximated target relationship model according to the boundary conditions and the first constraint condition of the profile radius of the cam 522 and the motor rotation angle of the rotation wheel 521 to obtain the solution set of the profile radius of the cam 522.

[0239] According to the cam profile design device of the cable-driven joint module provided by the embodiments of the present application, by means of system parameters such as the profile radius and profile length of the cam 522 and the kinematic relationship between the cam 522 driving the driving cable 300 to inhale and exhale, a target relationship model regarding the profile radius is established, and the track profile is jointly solved under the constraint that the curvature is positive. The designed cam 522 can achieve bidirectional rotation of the rotating joint driven by a single rotating wheel 521, ensuring the control accuracy and motion stability of the cable-driven joint module.

[0240] In some embodiments, the sixth processing module 1170 is configured to approximately process the first constraint condition according to the change of the profile radius of the cam 522 relative to the motor rotation angle of the rotating wheel 521 being less than or equal to the square of the target coefficient and much less than 1.

[0241] When the first constraint condition after the approximation processing is satisfied and the change of the profile radius of the cam 522 relative to the motor rotation angle of the rotating wheel 521 is less than or equal to the square of the target coefficient and much less than 1, the boundary conditions are determined, and the target relationship model after the approximation processing is solved.

[0242] In some embodiments, the sixth processing module 1170 is configured to optimize the target coefficient to determine the optimal target coefficient, and the approximation error between the target relationship model corresponding to the optimal target coefficient and the first constraint condition is the smallest.

[0243] Based on the optimal target coefficient, the boundary conditions are determined.

[0244] In some embodiments, the sixth processing module 1170 is configured to search for the optimal target coefficient by the bisection method.

[0245] In some embodiments, the profile length of the cam 522 is calculated by the Pythagorean theorem based on the profile radius of the cam 522 and the motor rotation angle of the rotating wheel 521.

[0246] The cam profile design device of the cable-driven joint module provided by the embodiments of the present application can achieve Figure 9 each process implemented by the method embodiments. To avoid repetition, it will not be elaborated here.

[0247] In some embodiments, as Figure 12 shown, the embodiments of the present application further provide an electronic device 1200, including a processor 1201, a memory 1202, and a computer program stored in the memory 1202 and executable on the processor 1201. When the program is executed by the processor 1201, it implements each process of the above-mentioned method embodiments of the cam profile design of the cable-driven joint module and can achieve the same technical effects. To avoid repetition, it will not be elaborated here.

[0248] It should be noted that the electronic devices in the embodiments of the present application include the above-mentioned mobile electronic devices and non-mobile electronic devices.

[0249] The embodiments of the present application also provide a non-transitory computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it implements each process of the above-mentioned embodiment of the cam profile design method of the cable-driven joint module, and can achieve the same technical effects. To avoid repetition, it will not be elaborated here.

[0250] Among them, the processor is the processor in the electronic device described in the above embodiments. The readable storage medium includes computer-readable storage media, such as computer read-only memory ROM, random access memory RAM, magnetic disks or optical discs, etc.

[0251] The embodiments of the present application also provide a computer program product, including a computer program. When the computer program is executed by a processor, it implements the above-mentioned cam profile design method of the cable-driven joint module.

[0252] Among them, the processor is the processor in the electronic device described in the above embodiments. The readable storage medium includes computer-readable storage media, such as computer read-only memory ROM, random access memory RAM, magnetic disks or optical discs, etc.

[0253] The embodiments of the present application further provide a chip, which includes a processor and a communication interface. The communication interface is coupled to the processor. The processor is used to run programs or instructions to implement each process of the above-mentioned embodiment of the cam profile design method of the cable-driven joint module, and can achieve the same technical effects. To avoid repetition, it will not be elaborated here.

[0254] It should be understood that the chip mentioned in the embodiments of the present application may also be referred to as a system-on-chip, system chip, chip system, or system-on-chip, etc.

[0255] It should be noted that in this text, the term "comprise", "include" or any other variant thereof is intended to cover non-exclusive inclusion, such that a process, method, article or apparatus comprising a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article or apparatus. Without further limitation, an element defined by the phrase "comprising an..." does not exclude the presence of additional identical elements in the process, method, article or apparatus comprising that element. In addition, it should be pointed out that the scope of the methods and apparatuses in the embodiments of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in a reverse order according to the functions involved. For example, the described methods may be performed in an order different from that described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

[0256] Through the description of the above embodiments, those skilled in the art can clearly understand that the above-described example methods can be implemented by means of software plus a necessary general hardware platform. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation. Based on such an understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art, can be embodied in the form of a computer software product. The computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions for causing a terminal (which can be a mobile phone, computer, server, or network device, etc.) to execute the methods described in various embodiments of the present application.

[0257] In the description of the present application, it should be understood that the orientation or positional relationship indicated by terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", "clockwise", "counterclockwise", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present application.

[0258] In the description of the present application, "the first feature", "the second feature" may include one or more of such features.

[0259] In the description of the present application, the meaning of "a plurality of" is two or more.

[0260] In the description of the present application, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact through additional features therebetween.

[0261] In the description of the present application, the first feature being "above", "over", and "on" the second feature includes the first feature being directly above and obliquely above the second feature, or simply indicating that the horizontal height of the first feature is higher than that of the second feature.

[0262] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0263] Although the embodiments of the present application have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the claims and their equivalents.

Claims

1. A rope-driven joint module, characterized in that Comprising: A first joint part and a second joint part; A driving module, the driving module includes a central rod, two first driving ropes and two second driving ropes, and two ends of the central rod are respectively arranged at the central positions of the ends of the first joint part and the second joint part; Two ends of each of the first driving ropes are respectively arranged at the ends of the first joint part and the second joint part, and the two first driving ropes are symmetrically distributed with respect to the central rod; two ends of each of the second driving ropes are respectively arranged at the ends of the first joint part and the second joint part, and the two second driving ropes are symmetrically distributed with respect to the central rod; A connecting line of two connection points of the two first driving ropes and the first joint part forms a first rotation axis, a connecting line of two connection points of the two second driving ropes and the first joint part forms a second rotation axis, and the first rotation axis and the second rotation axis are vertically intersected at the central position of the end of the first joint part; Wherein, the second joint part is used for rotating along the first rotation axis to realize the first-degree-of-freedom rotation, and the second joint part is used for rotating along the second rotation axis to realize the second-degree-of-freedom rotation.

2. The cable-driven joint module according to claim 1, wherein The driving module further includes: A first driving device, the first ends of the two first driving ropes are wound around the output end of the first driving device, the second ends of the two first driving ropes are connected to the second joint part, and the first driving device is arranged on the first joint part.

3. The cable-driven joint module according to claim 2, wherein, The first driving device is used for driving the second joint part to rotate along the second rotation axis through the two first driving ropes, and the length of the second driving rope between the first joint part and the second joint part is equal to the length of the central rod.

4. The cable-driven joint module according to claim 1, characterized in that, The driving module further includes: A second driving device, the first ends of the two second driving ropes are wound around the output end of the second driving device, the second ends of the two second driving ropes are connected to the second joint part, and the second driving device is arranged on the first joint part.

5. The cable-driven joint module according to claim 4, wherein, The second driving device is used for driving the second joint part to rotate along the first rotation axis through the two second driving ropes, and the length of the first driving rope between the first joint part and the second joint part is equal to the length of the central rod.

6. The cable-driven joint module according to any one of claims 1-5, characterized in that, The end of the first joint part facing the second joint part is a plane, and the end of the second joint part facing the first joint part is a plane.

7. The cable-driven joint module according to any one of claims 1-5, characterized in that One end of the central rod is hinged to the first joint part, and the other end of the central rod is fixedly connected to the second joint part.

8. The cable-driven joint module according to claim 7, characterized in that, One end of the central rod is provided with a spherical hinge structure, and one end of the central rod is hinged to the first joint part through the spherical hinge structure.

9. A robotic arm, characterized in that, Comprising: At least one rope-driven joint module according to any one of claims 1-8.

10. A robot, characterized in that, Comprising: At least one robotic arm according to claim 9.

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