Degree-of-freedom switching method and ankle joint mechanism

Abstract

The invention discloses a degree-of-freedom switching method, which comprises the following steps of: judging the operating degree of freedom of a simulation foot based on an application scene; when the degree of freedom is single, the two ends of the connecting shaft are fixedly connected with the mounting base, the first module or the second module drives the input end of the mounting base to rotate around the hinging part of the connecting shaft, and the simulation foot generates pitching action; when the driving force is two degrees of freedom, the two ends of the connecting shaft are movably connected with the mounting base, the first module and the second module drive the input end of the mounting base to rotate around the hinged part of the connecting shaft, the simulation foot generates pitching and two-side overturning actions, and when the driving force of the first module and the driving force of the second module are inconsistent, the simulation foot generates two-side overturning actions. The simulation foot has the beneficial effects that based on different degrees of freedom required for applying different scenes to the simulation foot in actual use, the operation degrees of freedom of the simulation foot can be quickly switched by changing the connection mode of the two ends of the connecting shaft and the mounting seat.

Description

Technical Field

[0001] The present invention relates to the technical field of robot manufacturing, and particularly to a method for switching degrees of freedom and an ankle joint mechanism. Background Art

[0002] At present, the ankle joints of humanoid robots are divided into double degrees of freedom and single degree of freedom. The more degrees of freedom a humanoid robot has, the more flexible its movements are. However, more degrees of freedom will lead to an increase in control complexity, increase the difficulty of software development and hardware costs, and also affect the battery life. In a specific environment, too many degrees of freedom will instead waste resources.

[0003] Most of the current humanoid robot ankle joints have double degrees of freedom. However, in practical scenarios such as industrial handling on flat ground with fixed paths, only a single degree of freedom at the ankle joint is required to meet the requirements. The double-degree-of-freedom solution is already functionally redundant, increasing costs and power consumption and affecting the battery life. The double degrees of freedom have high flexibility and can adapt to complex terrains, but the control complexity, cost, and energy consumption are high. How to quickly switch between double degrees of freedom and single degree of freedom as much as possible without increasing the operating cost so that the robot can quickly adapt to different working conditions is a problem that needs to be solved by those skilled in the art.

[0004] The information disclosed in this background art section is only intended to enhance the overall understanding of the present invention and should not be regarded as an admission or any form of suggestion that this information constitutes prior art known to those of ordinary skill in the art. Summary of the Invention

[0005] The technical problem to be solved by the present invention is: how to quickly switch the degrees of freedom of the ankle joint of a humanoid robot based on different working conditions without increasing the operating cost.

[0006] The present invention solves the above technical problem by the following technical means:

[0007] The present invention claims to protect a method for switching degrees of freedom, including:

[0008] Based on the application scenario, determine the operating degrees of freedom of the simulation foot;

[0009] When it is a single degree of freedom, both ends of the connecting shaft are fixedly connected to the mounting seat, and the first module or the second module drives the input end of the mounting seat to rotate around the hinge part of the connecting shaft, and the simulation foot generates a pitching motion.

[0010] When it is a double degree of freedom, both ends of the connecting shaft are movably connected to the mounting seat, and the first module and the second module drive the input end of the mounting seat to rotate around the hinge part of the connecting shaft, and the simulation foot generates pitching and two-side flipping motions. Among them, when the driving forces of the first module and the second module are inconsistent, the simulation foot generates two-side flipping motions.

[0011] The present invention claims protection for an ankle joint mechanism with switchable degrees of freedom, which is applied to a degree of freedom switching method, comprising a first module and a second module, wherein the first module and the second module are arranged in a simulated calf, and the positions of the first module and the second module are staggered with each other;

[0012] It also includes a connecting shaft and a mounting seat. The connecting shaft body is adapted to cooperate with the bottom end of the simulated calf to form a connecting shaft hinge portion. Both ends of the connecting shaft are movably connected or fixedly connected to the mounting seat. A simulated foot is installed at the bottom of the mounting seat. The mounting seat behind the simulated foot is extended to form an input end of the mounting seat. The first module and the second module are respectively coupled on both sides of the input end of the mounting seat, wherein the first module and the second module are configured to drive the corresponding sides of the input end of the mounting seat to generate a moving action along the length direction of the simulated calf.

[0013] Preferably, the bottom end of the simulated calf is in an inverted U-shaped structure, and a connecting shaft is placed in the inner part. The connecting shaft is in a cross structure, and the two ends of the connecting shaft wide axis cooperate with the simulated calf adapter to form a connecting shaft hinge part, and the two ends of the connecting shaft long axis are movably connected or fixedly connected to the mounting seat.

[0014] Preferably, the mounting seat includes a base and a bottom frame, the bottom frame has a U-shaped cross-section configuration, and a connecting shaft is placed in the internal part, the long axis of the connecting shaft is movably connected or fixedly connected to the bottom frame, and the base is installed on the bottom frame behind the simulation foot, and the two sides of the base are respectively coupled with the first module output end and the second module output end to form the input end of the mounting seat.

[0015] Preferably, the long axis of the connecting shaft includes a long axis body and a limiting cam shaft. The long axis body is arranged in the base frame, and sockets are provided at both ends of the long axis body. Corresponding through holes are provided on both sides of the base frame. The limiting cam shaft passes through the through hole and is plugged into and matched with the socket until the shoulder of the limiting cam shaft and the long axis body are in conflict with each other.

[0016] Preferably, a first bearing is arranged between the base frame and the limiting cam shaft, a fastening screw passes through the limiting cam shaft in the axial direction and is connected to the long axis body, and the base frame and the limiting cam shaft are movably connected or fixedly connected.

[0017] Preferably, the limiting convex shaft is provided with a second screw hole in the radial direction, and a mounting hole is correspondingly provided on the upper surface of the base frame, and the bolt passes through the mounting hole and is engaged with the second screw hole.

[0018] Preferably, the base includes a bottom plate, a capstan and a pin. The bottom plate is installed on the bottom side of the frame behind the artificial foot. The capstan is set on the upper surface of the bottom plate. The capstan is connected to the pin. The axis of the pin is parallel to the axis of the wide axis of the connecting shaft. The two ends of the pin are respectively connected to the output end of the first module and the output end of the second module.

[0019] Preferably, the first module includes a first driving unit, a first swing rod, and a first connecting rod. The first driving unit is arranged on the simulated calf. The driving end of the first driving unit is connected to one end of the first swing rod. The other end of the first swing rod is connected to the first connecting rod. One end of the bottom end of the first connecting rod is a transfer pin shaft. A second bearing is arranged between the pin shaft and the first connecting rod. Wherein, the bottom end of the first connecting rod constitutes the output end of the first module.

[0020] Preferably, the second module includes a second driving unit, a second swing rod, and a second connecting rod. The second driving unit is arranged on the simulated calf. The driving end of the second driving unit is connected to one end of the second swing rod. The other end of the second swing rod is connected to the second connecting rod. One end of the bottom end of the second connecting rod is a transfer pin shaft. A third bearing is arranged between the pin shaft and the second connecting rod. Wherein, the bottom end of the second connecting rod constitutes the output end of the second module.

[0021] The advantages of the present invention are as follows:

[0022] First, the present invention claims to protect a method for switching degrees of freedom. Based on actual use, different scenarios require different degrees of freedom for the simulated foot. The degrees of freedom of the simulated foot can be quickly switched by changing the connection method between the two ends of the connecting shaft and the mounting base. For example, when the simulated foot is on complex terrain, it can be switched to a two-degree-of-freedom mode, that is, the simulated foot generates pitching and lateral flipping movements, making the overall flexibility high. When the simulated foot is on simple terrain, it can be switched to a single-degree-of-freedom mode, which is easy to control, has low power consumption, and relatively reduces costs. Therefore, the overall applicability is high.

[0023] Second, the present invention also claims to protect an ankle joint mechanism with switchable degrees of freedom. The ankle joint mechanism for switching two degrees of freedom shares structures such as the first module, the second module, and the connecting shaft. Except for the different connection methods between the two ends of the connecting shaft and the mounting base, it can be imagined that during the switching process, the disassembly and assembly are convenient. There is no need to re-design the ankle joint mechanism, nor to re-design the installation of the simulated calf and the simulated foot, and there is no need to set up multiple sets of driving modules. It can achieve quick switching, greatly reducing the workload of design and development, which is of great significance for the mass production, debugging of humanoid robot products, and actual use by users.

[0024] Third, the connecting shaft has a cross shape. Not only can the wide axis of the connecting shaft provide an installation space for the simulated calf, enabling the connecting shaft to rotate around the hinge part of the connecting shaft to achieve the pitching movement of the simulated foot, but also the long axis of the connecting shaft provides an installation space for the mounting base, laying a foundation for the lateral flipping movement of the simulated foot.

[0025] Fourth, the two sides of the base are respectively coupled with the output end of the first module and the output end of the second module to play two main roles. The first role is that when it is a double degree of freedom, the output power of the output end of the first module and the output end of the second module can be transmitted. When the driving force of the output end of the first module and the second module is inconsistent, the two sides of the driving base produce a movement trend of flipping on both sides. The second role is that when it is a single degree of freedom, at this time, the two ends of the connecting shaft are fixedly connected to the mounting seat. When the driving force of the output end of the first module and the second module is inconsistent, the connecting shaft limits the flipping of the mounting seat, and the coupling of the input end of the base can prevent the output end of the first module and the output end of the second module from moving in a small range by mistake, resulting in a constraint with the base.

[0026] 5. The purpose of setting the limit cam is mainly to facilitate the disassembly of the chassis and to prepare for the switching of degrees of freedom. In actual use, if the chassis is installed, the limit cam can be passed through the through hole and plugged into the socket until the limit cam shoulder contacts the long shaft body.

[0027] 6. Combined with the above description, it can be known that when switching the dual degrees of freedom, it is mainly through the active connection of the base frame and the limiting cam shaft. Preferably, a first bearing is set between the base frame and the limiting cam shaft to increase the degree of freedom between the base frame and the connecting shaft, and then the fastening screw is axially passed through the connecting limiting cam shaft to avoid the axial slip of the base frame along the limiting cam shaft, so that when the driving force of the first module and the second module is different, flipping of the two sides can be achieved.

[0028] 7. When switching to a single degree of freedom, it is preferred to pass the bolts through the base frame radially along the limiting cam to engage with the limiting cam to achieve fixation between the base frame and the connecting shaft, and then cooperate with the base input end coupling to avoid constraints between the first module output end and the second module output end and the base, so that the base can only produce pitch movements around the connecting shaft hinge. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic diagram of the structure of the ankle joint mechanism with two degrees of freedom in the first embodiment of the present invention;

[0030] Figure 2 It is an exploded schematic diagram of the connecting shaft, the mounting seat, the fastening screw and the first bearing in the first embodiment of the present invention;

[0031] Figure 3 It is a schematic structural diagram of the limiting convex shaft in the first embodiment of the present invention;

[0032] Figure 4 This is a schematic diagram of the connecting shaft structure in Embodiment 1 of the present invention;

[0033] Figure 5 It is a schematic diagram of the cutaway structure of the ankle joint mechanism with two degrees of freedom in the first embodiment of the present invention;

[0034] Figure 6This is a schematic diagram of the structure of the ankle joint mechanism with a single degree of freedom in the second embodiment of the present invention;

[0035] Figure 7 This is a schematic diagram of the connecting shaft, mounting seat, and bolt connection structure in the second embodiment of the present invention;

[0036] Figure 8 It is an exploded schematic diagram of the connecting shaft, the mounting seat, and the bolts in the second embodiment of the present invention;

[0037] Figure 9 It is a schematic diagram of the cross-section structure of the ankle joint mechanism with a single degree of freedom in the second embodiment of the present invention.

[0038] 1. First module; 10. First drive unit; 11. First swing arm; 12. First connecting rod; 2. Second module; 20. Second drive unit; 21. Second swing arm; 22. Second connecting rod; 3. Connecting shaft; 301. Long axis body; 302. Limiting cam; 4. Mounting seat; 40. Base frame; 41. Base; 410. Bottom plate; 411. Capstan seat; 412. Pin; 5. First bearing; 6. Bolt; 7. Fastening screw. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] Embodiment 1

[0041] See also Figure 1 The present embodiment provides an ankle joint mechanism with switchable degrees of freedom, comprising a first module 1, a second module 2, a connecting shaft 3 and a mounting seat 4. The simulated calf is provided with the first module 1 and the second module 2, and the positions of the first module 1 and the second module 2 are staggered with each other; the connecting shaft 3 is coupled to the bottom end of the simulated calf to form a hinged portion of the connecting shaft 3, the bottom end of the simulated calf is in an inverted U-shaped structure, and the connecting shaft 3 is placed in the inner part, the connecting shaft 3 is in a cross structure, the two ends of the wide axis of the connecting shaft 3 are coupled to the simulated calf to form a hinged portion of the connecting shaft 3, and the two ends of the long axis of the connecting shaft 3 are movably connected to the mounting seat 4. The connecting shaft 3 is in a cross structure, and not only can the wide axis of the connecting shaft 3 provide an installation space for the simulated calf, but also can rotate around the hinged portion of the connecting shaft 3 to realize the pitching action of the simulated foot. In addition, the long axis of the connecting shaft 3 also provides an installation space for the mounting seat 4, laying a foundation for the flipping action on both sides of the simulated foot. The simulated foot is installed at the bottom of the mounting seat 4, and the mounting seat 4 behind the simulated foot is extended to form the input end of the mounting seat 4.

[0042] See also Figures 1 to 5 , the first module 1 and the second module 2 are coupled to both sides of the input end of the mounting seat 4, the first module 1 includes a first driving unit 10, a first swing rod 11 and a first connecting rod 12, the simulation calf is provided with a first driving unit 10, the driving end of the first driving unit 10 is connected to one end of the first swing rod 11, the other end of the first swing rod 11 is connected to the first connecting rod 12, the bottom end of the first connecting rod 12 is connected to one end of the pin shaft 412, and a second bearing is arranged between the pin shaft 412 and the first connecting rod 12, wherein the bottom end of the first connecting rod 12 constitutes the output end of the first module 1, the second module 2 includes a second driving unit 20, a second swing rod 21 and a second connecting rod 22, the simulation calf is provided with a second driving unit 20, the driving end of the second driving unit 20 is connected to one end of the second swing rod 21, and the second The other end of the rocker arm 21 is connected to the second connecting rod 22, and the bottom end of the second connecting rod 22 is connected to one end of the pin shaft 412, and a third bearing is arranged between the pin shaft 412 and the second connecting rod 22, wherein the bottom end of the second connecting rod 22 constitutes the output end of the second module 2, wherein the first module 1 and the second module 2 are configured to drive the corresponding sides of the input end of the mounting seat 4 to produce a moving movement along the length direction of the simulated calf, and the two sides of the base 41 are respectively coupled with the output end of the first module 1 and the output end of the second module 2, which mainly play two roles. The first role is that when it is a double degree of freedom, the output power of the output end of the first module 1 and the output end of the second module 2 can be transmitted. When the driving force of the output end of the first module 1 and the second module 2 is inconsistent, the two sides of the driving base 41 produce a movement trend of flipping on both sides. Function 2: When it is a single degree of freedom, at this time, both ends of the connecting shaft 3 are fixedly connected to the mounting seat 4. When the driving force of the output end of the first module 1 and the driving force of the second module 2 are inconsistent, the connecting shaft 3 limits the flipping of the mounting seat 4, and the coupling of the input end of the base 41 can avoid the output end of the first module 1 and the output end of the second module 2 from being constrained by the base 41.

[0043] The mounting base 4 includes a chassis 40 and a base 41. The chassis 40 has a U-shaped cross-sectional configuration, and the connecting shaft 3 is placed inside. The long axis of the connecting shaft 3 includes a long axis body 30 and a limiting convex shaft 31. The long axis body 30 is arranged inside the chassis 40. Jacks are opened at both ends of the long axis body 30. Through holes penetrate through the two sides of the chassis 40 correspondingly. The limiting convex shaft 31 passes through the through holes and is inserted into the jacks until the shoulder of the limiting convex shaft 31 abuts against the side surface of the chassis 40 and the long axis body 30. The fastening screw 7 axially passes through and connects the limiting convex shaft 31 and is connected to the long axis body 30. The chassis 40 is movably connected to the limiting convex shaft 31. The setting of the limiting convex shaft 31 is mainly to facilitate the disassembly of the chassis 40 and prepare for the freedom degree switching. During actual use, when installing the chassis, the limiting convex shaft can pass through the through hole and be inserted into the jack until the shoulder of the limiting convex shaft 31 abuts against the side surface of the chassis 40 and the long axis body 30. Then, in cooperation with the fastening screw 7 axially passing through and connecting the limiting convex shaft 31, the chassis is prevented from sliding axially along the limiting convex shaft. A first bearing 5 is arranged between the chassis 40 and the limiting convex shaft 31. From the above description, it can be known that when switching the double freedom degree, mainly by movably connecting the chassis 40 and the limiting convex shaft 31, preferably by arranging a first bearing 5 between the chassis 40 and the limiting convex shaft 31, the fastening screw 7 axially passes through and connects the limiting convex shaft 31 and is connected to the long axis body 30. The chassis 40 is movably or fixedly connected to the limiting convex shaft 31 to increase the freedom degree between the chassis 40 and the connecting shaft 3. Thus, when the driving forces of the first module 1 and the second module 2 are different, the two sides can be flipped. The base 41 is installed on the chassis 40 facing the back of the simulation foot. The base 41 includes a bottom plate 410, a hinge seat 411 and a pin shaft 412. The bottom plate 410 is installed on the bottom side of the chassis 40 facing the back of the simulation foot. The hinge seat 411 is arranged on the upper plate surface of the bottom plate 410. The pin shaft 412 is connected in a rotating manner. The axis of the pin shaft 412 is parallel to the width axis of the connecting shaft 3. The two ends of the pin shaft 412 are respectively connected to the output ends of the first module 1 and the second module 2 in a rotating manner.

[0044] Embodiment 2

[0045] Refer to Figures 6 to 9 , in this embodiment, the difference from Embodiment 1 is that: both ends of the long axis of the connecting shaft 3 are fixedly connected to the mounting base 4. Specifically, a second screw hole is radially opened on the limiting convex shaft 31, and a mounting hole is correspondingly opened on the upper surface of the chassis 40. The bolt 6 passes through the mounting hole and is meshed and connected to the second screw hole. When switching to a single degree of freedom, preferably, the bolt 6 is radially passed through the chassis 40 along the limiting convex shaft 31 and meshed with the limiting convex shaft 31 to fix the chassis 40 and the connecting shaft 3. Then, in cooperation with the coupling of the input end of the base 41, the output ends of the first module 1 and the second module 2 and the base 41 are prevented from jamming, so that the base 41 can only produce a pitching motion around the hinge part of the connecting shaft.

[0046] This embodiment claims to protect an ankle joint mechanism with switchable degrees of freedom. The ankle joint mechanisms for switching between two degrees of freedom share structures such as the first module 1, the second module 2, and the connecting shaft 3. It can be imagined that during switching, the disassembly and assembly are convenient. There is no need to redesign the ankle joint mechanism, nor to redesign the installation of the simulated calf and the simulated foot. Moreover, there is no need to set up multiple sets of drive modules, and rapid switching can be achieved, greatly reducing the workload of design and development, which is of great significance for the mass production, debugging of humanoid robot products, and actual use by users.

[0047] Embodiment III

[0048] Based on Embodiment I and Embodiment II, this embodiment provides a method for switching degrees of freedom for the degree-of-freedom switching of the ankle joint mechanism. Among them, the first drive unit 10 is preferably the upper ankle joint module, and the second drive unit 20 is preferably the lower ankle joint module. The operating logic of the lower ankle joint module is specifically that the lower ankle joint module drives the first swing rod 11 to swing, and the first swing rod 11 drives the first connecting rod 12 to move up and down, similar to a crank-slider mechanism. This is the prior art for the single-degree-of-freedom control of the ankle joint mechanism and will not be elaborated here. The operating logic of the upper ankle joint module refers to that of the lower ankle joint module and will not be elaborated here. The connecting shaft 3 is preferably a cross shaft. Among them, the wide axis of the connecting shaft 3 is the axis of the cross shaft in the width direction, and the long axis of the connecting shaft 3 is the axis of the cross shaft in the length direction. In actual work, in order to more accurately control the operation of the simulated foot, it is preferably to be further equipped with a six-axis force sensor, which is arranged between the mounting seat 4 and the simulated foot and is connected to each other by screws. The six-axis force sensor mainly provides accurate force feedback, enabling the simulated foot to adjust its own actions according to real-time force information and achieve more compliant and accurate operations. This is the prior art and will not be elaborated here. Based on the above description, a method for switching degrees of freedom includes:

[0049] Determine the degree of freedom of the simulated foot operation based on the application scenario;

[0050] When it is a single degree of freedom, first, both ends of the connecting shaft 3 are fixedly connected to the mounting seat 4, and the first module 1 or the second module 2 drives the input end of the mounting seat 4 to rotate around the hinge part of the connecting shaft 3, and the simulated foot generates a pitching motion; specifically, when the ankle joint mechanism has a single degree of freedom, remove the fastening screw 7, disassemble the limit convex shaft 16, and remove the first bearing 5.

[0051] Secondly, insert the limiting convex shaft 16 into the through hole and the jack. The shoulder of the limiting convex shaft 16 and the long shaft body 30 limit the relative rotation of the long shaft body 30 and the limiting convex shaft 16. Tighten the bolt 6 to fix the mounting seat 4 and the limiting convex shaft 16. Then, the mounting seat 4 and the connecting shaft 3 cannot rotate relative to each other, reducing one degree of freedom of swing. At this time, only one of the first module 1 and the second module 2 can be retained for the pitch degree of freedom, or both the first module 1 and the second module 2 can be retained, with one following the other to improve fault tolerance. Taking the second driving unit 20 as an example, specifically, the lower ankle joint module drives the first swing rod 11 to swing. The first swing rod 11 drives the first connecting rod 12 to move up and down, causing the mounting seat 4 to perform a pitching motion. A six-axis force sensor is arranged between the mounting seat 4 and the simulation foot, and the simulation foot also performs a pitching motion.

[0052] When there are two degrees of freedom, first, both ends of the connecting shaft 3 are movably connected to the mounting seat 4. The first module 1 and the second module 2 drive the input end of the mounting seat 4 to rotate around the hinge part of the connecting shaft 3, and the simulation foot generates pitching and lateral flipping motions. Among them, when the driving forces of the first module 1 and the second module 2 are inconsistent, the simulation foot generates lateral flipping motions. Specifically, a first bearing 5 is inserted between the long shaft ends of the mounting seat 4 and the connecting shaft 3, and the locking screw is screwed into the long shaft body 30 to lock the first bearing 5. The long shaft body 30 can rotate relative to the mounting seat 4.

[0053] Secondly, the lower ankle joint module drives the first swing rod 11 to swing. The first swing rod 11 drives the first connecting rod 12 to move up and down, driving the mounting seat 4 to perform a pitching motion. A six-axis force sensor is arranged between the mounting seat 4 and the simulation foot, and the simulation foot also performs a pitching motion. Similarly, the upper ankle joint module drives the second swing rod 21 to swing. The second swing rod 21 drives the second connecting rod 22 to move up and down, causing the mounting seat 4 to perform a pitching motion. When the driving forces of the first module 1 and the second module 2 are inconsistent, that is, when the second connecting rod 22 and the first connecting rod 12 move inconsistently, the mounting seat 4 performs a left-right swinging motion through the long shaft body 30. Therefore, the simulation foot has two degrees of freedom, namely pitching and lateral flipping, at this time.

[0054] This embodiment claims to protect a method for switching degrees of freedom. Based on the actual use, different scenarios require different degrees of freedom for the simulation foot. The degrees of freedom of the simulation foot can be quickly switched by changing the connection method between both ends of the connecting shaft 3 and the mounting seat 4. For example, when the simulation foot is in a complex terrain, it can be switched to two degrees of freedom, that is, the simulation foot generates pitching and lateral flipping motions, making the overall flexibility high. When the simulation foot is in a simple terrain, it can be switched to one degree of freedom, which is easy to control, has low power consumption, and relatively reduces costs. Therefore, the overall applicability is high.

[0055] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A degree of freedom switching method, characterized in that include: Based on the application scenario, determine the freedom of movement of the simulation foot; When it is a single degree of freedom, the two ends of the connecting shaft (3) are fixedly connected to the mounting seat (4), and the first module (1) or the second module (2) drives the input end of the mounting seat (4) to rotate around the hinged part of the connecting shaft (3), so that the artificial foot produces pitching motion; When there are two degrees of freedom, the two ends of the connecting shaft (3) are movably connected to the mounting seat (4), the first module (1) and the second module (2) drive the input end of the mounting seat (4) to rotate around the hinge part of the connecting shaft (3), and the simulation foot produces pitching and flipping movements on both sides, wherein when the driving forces of the first module (1) and the second module (2) are inconsistent, the simulation foot produces flipping movements on both sides.

2. A switchable-degree-of-freedom ankle joint mechanism, applied to the degree-of-freedom switching method described in claim 1, characterized in that, The simulated calf comprises a first module (1) and a second module (2), wherein the first module (1) and the second module (2) are arranged on the simulated calf, and the positions of the first module (1) and the second module (2) are staggered with each other; The invention also comprises a connecting shaft (3) and a mounting seat (4), wherein the connecting shaft (3) is connected to the bottom end of the simulated calf to form a hinged portion of the connecting shaft (3), and the two ends of the connecting shaft (3) are movably connected or fixedly connected to the mounting seat (4), and a simulated foot is arranged at the bottom of the mounting seat (4), and the mounting seat (4) is extended toward the back of the simulated foot to form an input end of the mounting seat (4), and the two sides of the input end of the mounting seat (4) are respectively coupled to the first module (1) and the second module (2), wherein the first module (1) and the second module (2) are configured to drive the corresponding sides of the input end of the mounting seat (4) to generate a movement along the length direction of the simulated calf.

3. The ankle joint mechanism with switchable degrees of freedom according to claim 2, characterized in that The bottom end of the simulated calf is in an inverted U-shaped structure, and a connecting shaft (3) is placed in the inner part. The connecting shaft (3) is in a cross structure. The two ends of the wide axis of the connecting shaft (3) cooperate with the simulated calf adapter to form a hinge part of the connecting shaft (3), and the two ends of the long axis of the connecting shaft (3) are movably connected or fixedly connected to the mounting seat (4).

4. The ankle joint mechanism with switchable degrees of freedom according to claim 2, characterized in that, The mounting seat (4) comprises a base frame (40) and a base (41); the base frame (40) is of U-shaped cross-section configuration, and a connecting shaft (3) is placed in the inner part; the long axis of the connecting shaft (3) is movably connected or fixedly connected to the base frame (40); the base (41) is arranged on the base frame (40) facing the rear of the artificial foot; two sides of the base (41) are respectively coupled with the output end of the first module (1) and the output end of the second module (2) to form the input end of the mounting seat (4).

5. The ankle joint mechanism with switchable degrees of freedom according to claim 1, characterized in that, The long axis of the connecting shaft (3) comprises a long axis body (301) and a limiting convex shaft (302). The long axis body (301) is arranged in the base frame (40). Insertion holes are provided at both ends of the long axis body (301). The two sides of the base frame (40) have corresponding through holes. The limiting convex shaft (302) passes through the through holes and is plugged into the insertion hole until the shaft shoulder of the limiting convex shaft (302) contacts and cooperates with the long axis body (301).

6. The ankle joint mechanism with switchable degrees of freedom according to claim 5, characterized in that, A first bearing (5) is arranged between the base frame (40) and the limiting convex shaft (302); a fastening screw (7) passes through the limiting convex shaft (302) in the axial direction and is connected to the long shaft body (301); and the base frame (40) and the limiting convex shaft (302) are movably connected or fixedly connected.

7. The ankle joint mechanism with switchable degrees of freedom according to claim 5, characterized in that, The limiting convex shaft (302) is provided with a second screw hole in the radial direction, and a mounting hole is correspondingly provided on the upper surface of the base frame (40), and the bolt (6) passes through the mounting hole and is meshed and connected with the second screw hole.

8. The ankle joint mechanism with switchable degrees of freedom according to claim 1, characterized in that, The base (41) includes a bottom plate (410), a hinge seat (411) and a pin shaft (412). The bottom plate (410) is installed on the bottom side of the chassis (40) facing the rear of the simulated foot. The hinge seat (411) is arranged on the upper surface of the bottom plate (410). The hinge seat (411) transfers the pin shaft (412). The axis of the pin shaft (412) is parallel to the wide-axis of the connecting shaft (3). The two ends of the pin shaft (412) transfer the output ends of the first module (1) and the second module (2) respectively.

9. The ankle joint mechanism with switchable degrees of freedom according to claim 2, characterized in that, The first module (1) includes a first driving unit (10), a first swing rod (11) and a first connecting rod (12). The first driving unit (10) is arranged on the simulated calf. The driving end of the first driving unit (10) is connected to one end of the first swing rod (11). The other end of the first swing rod (11) is connected to the first connecting rod (12). The bottom end of the first connecting rod (12) transfers one end of the pin shaft (412). A second bearing is arranged between the pin shaft (412) and the first connecting rod (12). Among them, the bottom end of the first connecting rod (12) constitutes the output end of the first module (1).

10. The ankle joint mechanism with switchable degrees of freedom according to claim 2, characterized in that, The second module (2) includes a second driving unit (20), a second swing rod (21) and a second connecting rod (22). The second driving unit (20) is arranged on the simulated calf. The driving end of the second driving unit (20) is connected to one end of the second swing rod (21). The other end of the second swing rod (21) is connected to the second connecting rod (22). The bottom end of the second connecting rod (22) transfers one end of the pin shaft (412). A third bearing is arranged between the pin shaft (412) and the second connecting rod (22). Among them, the bottom end of the second connecting rod (22) constitutes the output end of the second module (2).

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