Leg structure and mechanism

Abstract

The present invention discloses a leg structure and a mechanical device, wherein the leg structure includes a driving assembly, a driving arm, a driven arm and a buffer assembly, wherein the buffer assembly is switchably arranged on the driving arm or the driven arm between an initial state and a deformed state; the buffer assembly is used to be in the initial state when the reaction force transmitted to the driving assembly by the ground contact end is less than a preset reaction force; and is in a deformed state when the reaction force transmitted to the driving assembly by the ground contact end is greater than the preset reaction force, so as to alleviate the reaction force transmitted to the driving assembly by the ground contact end. When the foot rod of the leg structure proposed by the present invention is impacted by an external force, the instantaneous impact of the external force on the foot rod is sequentially transmitted to the buffer assembly to offset the reaction force acting on the driving shaft of the driving assembly, thereby avoiding damage to the first motor and the second motor, and prolonging the service life of the driving assembly. While not easily damaged, the operation of the entire leg structure is smoother and more stable.

Description

Technical Field

[0001] The present invention relates to the field of robotics technology, and in particular to a leg structure and a mechanical device. Background Art

[0002] In the prior art, after the foot rod of the robot's leg structure hits the ground from a high place, the instantaneous reaction force of the ground on the foot rod is transmitted to the drive motor, which will cause a strong reaction force on the motor and easily cause damage to the motor. While placing high requirements on the motor performance, it is not suitable for daily use. Summary of the Invention

[0003] The main purpose of the present invention is to propose a leg structure, which aims to solve the problem in the prior art that the driving motor is damaged when the ground-contacting end of the robot leg hits the ground from a high place or the leg is hit by an external force.

[0004] To achieve the above object, the present invention provides a leg structure, comprising a first connecting rod, a second connecting rod, a third connecting rod, a fourth connecting rod and a fifth connecting rod;

[0005] The first connecting rod and the second connecting rod are rotatably connected to form a first rotation fulcrum;

[0006] The third connecting rod is rotatably connected to the second connecting rod to form a second rotation fulcrum;

[0007] The third connecting rod and the fourth connecting rod are rotatably connected to form a third rotation fulcrum;

[0008] The second connecting rod and the fourth connecting rod are rotatably connected through a connecting member, and form a fourth rotation fulcrum and a fifth rotation fulcrum respectively;

[0009] The connecting line of the second rotation fulcrum, the third rotation fulcrum, the fourth rotation fulcrum and the fifth rotation fulcrum forms a quadrilateral;

[0010] One end of the fifth connecting rod is rotatably connected to the first connecting rod to form a sixth rotation fulcrum, the other end of the fifth connecting rod is a first driving end for driving connection with the first motor, and the third connecting rod has a second driving end for driving connection with the second motor, and the rotation axes of the first driving end and the second driving end are parallel;

[0011] A line connecting the first rotation fulcrum, the second rotation fulcrum, the sixth rotation fulcrum, the first driving end and the second driving end is a pentagon.

[0012] Optionally, the first connecting rod has a first input end and a first output end relative to each other, the second connecting rod has a second input end and a second output end relatively set, the first output end and the second input end are rotatably connected to form the first rotation fulcrum, the second rotation fulcrum is located between the second input end and the second output end, and the third rotation fulcrum is located between the second driving end and the second rotation fulcrum.

[0013] Optionally, the line connecting the second rotation fulcrum, the third rotation fulcrum, the fourth rotation fulcrum, and the fifth rotation fulcrum is a parallelogram.

[0014] Optionally, the third fulcrum is located between the second fulcrum and the second driving end.

[0015] Optionally, the connecting member extends from the fourth rotation fulcrum toward the fifth rotation fulcrum to form a support rod.

[0016] Optionally, the fifth connecting rod includes a first section and a second section, the first section and the second section are connected in a bent manner, the first driving end is arranged on the first section, and the second section is rotatably connected to the first connecting rod to form the sixth rotation fulcrum.

[0017] The present invention also provides another leg structure, comprising a first connecting rod, a second connecting rod, a third connecting rod, a fourth connecting rod and a fifth connecting rod;

[0018] The first connecting rod and the second connecting rod are rotatably connected to form a first rotation fulcrum;

[0019] The third connecting rod is rotatably connected to the second connecting rod to form a second rotation fulcrum;

[0020] The third connecting rod and the fourth connecting rod are rotatably connected to form a third rotation fulcrum;

[0021] The second connecting rod and the fourth connecting rod are rotatably connected by a connecting member, and form a fourth rotation fulcrum and a fifth rotation fulcrum respectively; the second fulcrum is located between the first fulcrum and the fifth fulcrum;

[0022] The connecting line of the second rotation fulcrum, the third rotation fulcrum, the fourth rotation fulcrum and the fifth rotation fulcrum forms a quadrilateral;

[0023] One end of the fifth connecting rod is rotatably connected to the third connecting rod to form a seventh rotation fulcrum, the other end of the fifth connecting rod is a second driving end for driving connection with the second motor, the first connecting rod has a first driving end for driving connection with the first motor, and the rotation axes of the first driving end and the second driving end are parallel;

[0024] A line connecting the first rotation fulcrum, the second rotation fulcrum, the seventh rotation fulcrum, the first driving end and the second driving end forms a pentagon.

[0025] Optionally, a line connecting the second rotation fulcrum, the third rotation fulcrum, the fourth rotation fulcrum, and the fifth rotation fulcrum is a parallelogram.

[0026] Optionally, the end of the first connecting rod away from the second driving end is the output end, and the output end is rotatably connected to one end of the second connecting rod to form the first rotation fulcrum, and the first rotation fulcrum and the fourth rotation fulcrum are respectively located at two ends of the second connecting rod.

[0027] Optionally, the fifth connecting rod includes a first section and a second section, the first section and the second section are connected in a bent manner, the first driving end is arranged on the first section, and the second section is rotationally connected to one end of the first connecting rod away from the second rotation to form the seventh rotation fulcrum.

[0028] The present invention also proposes a mechanical device, comprising any of the leg structures described above, wherein the mechanical device is a robot, a robot dog, a robot bird, a robot fish, a driving part, and a connecting part.

[0029] The leg structure proposed in the present invention includes a driving assembly, a driving arm, a driven arm and a buffer assembly, the driving assembly includes a first motor and a second motor; the driving arm has a first driving end and a second driving end, the first driving end is connected to the first motor, and the second driving end is connected to the second motor; the driven arm is connected to the driving arm in a transmission manner and follows the movement of the driving arm, and the driven arm has a ground-contacting end; the buffer assembly is switchable between an initial state and a deformation state on the driving arm or the driven arm; the buffer assembly is used to be in the initial state when the reaction force transmitted to the driving assembly by the ground-contacting end is less than a preset reaction force. When the reaction force transmitted from the ground contact end to the drive assembly is greater than the preset reaction force, the arm is deformed to mitigate the reaction force transmitted from the ground contact end to the drive assembly. This allows the leg structure's connector to be impacted and the ground contact end of the slave arm to come into contact with the ground. At this moment, the ground's reaction force on the ground contact end is much greater than the preset reaction force of the buffer assembly. Furthermore, the first and second motors do not provide rotational force to the drive arm at this moment. The buffer assembly then deforms to offset the ground's reaction force, mitigating the impact force transmitted from the ground contact end to the drive assembly, protecting the drive assembly and preventing damage to the first and second motors. This not only increases the service life of the drive assembly and makes it less susceptible to damage, but also prevents deformation of the entire leg structure, resulting in more stable operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

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

[0032] Figure 2 This is a schematic structural diagram of another embodiment of the leg structure of the present invention;

[0033] Figure 3 for Figure 1 Schematic diagram of the leg rod length structure;

[0034] Figure 4 Schematic diagram of the buffer structure of an embodiment of the leg structure of the present invention.

[0035] Description of Figure Numbers:

[0036] Label name Label name 10 Drive components 101 First Motor 102 Second motor 20 Drive arm 30 follower arm 21 Third link 22 Fifth link 31 First connecting rod 32 Second connecting rod 33 Fourth link 201 First drive end 202 Second drive end 40 Buffer components 34 Connectors 311 The first pivot point 321 Second rotation fulcrum 211 The third rotation fulcrum 322 Fourth rotation fulcrum 331 Fifth rotation fulcrum 221 Sixth rotation fulcrum 212 Seventh rotation fulcrum 312 First connecting part 313 Second connecting part 41 elastic parts 42 Guide rod 43 Guide sleeve 341 Ground contact end 431 guide groove 432 First blocking portion 433 Second blocking portion 434 Linear bearings 421 Limiting protrusion 342 connecting rod 103 case 2011 First active end 2012 First connection end

[0037] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments. DETAILED DESCRIPTION

[0038] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0039] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly.

[0040] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features specified as "first" and "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between the various embodiments can be combined with each other, but this must be based on the fact that ordinary technicians in this field can implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0041] In the prior art, when the ground-contacting end of the robot's leg hits the ground from a high position, the instantaneous reaction force of the ground on the foot rod is transmitted to the drive motor, which can easily cause damage to the motor.

[0042] The present invention provides a leg structure.

[0043] In one embodiment of the present invention, as shown in the figure, the leg structure includes a driving assembly 10, a driving arm 20, a driven arm 30 and a buffer assembly 40, wherein the driving assembly 10 includes a first motor 101 and a second motor 102. The driving arm 20 has a first driving end 201 and a second driving end 202, wherein the first driving end 201 is connected to the first motor 101 and the second driving end 202 is connected to the second motor 102; the driven arm 30 is in transmission connection with the driving arm 20 and follows the movement of the driving arm 20, and the driven arm 30 has a ground contact end 341 for contacting the ground. The buffer assembly 40 is switchable between an initial state and a deformed state and is arranged on the driving arm 20 or the driven arm 30; the buffer assembly 40 is used to be in the initial state when the reaction force transmitted to the driving assembly 10 by the ground contact end 341 is less than a preset reaction force. When the reaction force transmitted from the ground contact end 341 to the drive assembly 10 is greater than the preset reaction force, the leg structure is in a deformed state to alleviate the reaction force transmitted from the ground contact end 341 to the drive assembly 10. When the leg structure jumps from a height, the ground contact end 341 of the slave arm 30 contacts the ground. At this moment, the reaction force of the ground on the ground contact end 341 is much greater than the preset reaction force of the buffer assembly 40. At this time, the buffer assembly 40 deforms to offset the reaction force of the ground, alleviating the reaction force transmitted from the ground contact end 341 to the drive assembly 10, thereby protecting the drive assembly 10 and preventing damage to the rotating shafts of the first motor 101 and the second motor 102. While increasing the service life of the drive assembly 10 and making it less susceptible to damage, the entire leg structure will not deform, and its operation will be more stable.

[0044] In one embodiment, the buffer assembly 40 is provided on the driven arm 30. The driving arm 20 includes a third link 21 and a fifth link 22. The first driving end 201 of the third link 21 is rotatably connected to the first motor 101, and the second driving end 202 of the second link 32 is rotatably connected to the second motor 102. The driven arm 30 includes a first link 31, a second link 32, and a fourth link 33. The first link 31 and the second link 32 are rotatably connected to form a first rotation fulcrum 311. The third link 21 and the second link 32 are rotatably connected to form a second rotation fulcrum 321. The third link 21 and the fourth link 33 are rotationally connected to form a third rotation fulcrum 211; the second link 32 and the fourth link 33 are rotationally connected through the connecting member 34 to form a fourth rotation fulcrum 322 and a fifth rotation fulcrum 331 respectively, wherein the ground contact portion is located at one end of the connecting member 34; the line connecting the second rotation fulcrum 321, the third rotation fulcrum 211, the fourth rotation fulcrum 322, and the fifth rotation fulcrum 331 is a quadrilateral.

[0045] Among them, one end of the fifth connecting rod 22 is rotatably connected to the first connecting rod 31 to form a sixth rotating fulcrum 221, and the other end of the fifth connecting rod 22 is a first driving end 201 for driving and connecting to the first motor 101, and the third connecting rod 21 has a second driving end 202 for driving and connecting to the second motor 102, and the rotation axes of the first driving end 201 and the second driving end 202 are parallel; the line connecting the first rotating fulcrum 311, the second rotating fulcrum 321, the sixth rotating fulcrum 221, the first driving end 201 and the second driving end 202 is a pentagon.

[0046] When the first drive end 201 of the fifth connecting rod 22 is driven by the first motor 101, the fifth connecting rod 22 rotates about the rotation centerline of the first drive end 201, thereby driving the first connecting rod 31 to rotate about the sixth rotation fulcrum 221, the second connecting rod 32 to rotate about the first rotation fulcrum 311, and the fourth connecting rod 33 to rotate about the third rotation fulcrum 211. The connecting member 34 follows the fourth connecting rod 33 about the fifth rotation fulcrum 331 and follows the second connecting rod 32 about the fourth rotation fulcrum 322, respectively. The third connecting rod 21 rotates along with the second connecting rod 32. When one of the drive ends is driven, the entire connecting rod structure can be driven, eliminating the need for additional drive parts or electronic components on the rod body. This makes the entire leg structure purely mechanical, highly reliable, and easy to maintain. Depending on the needs of use, when the first drive end 201 of the fifth link 22 is driven, the second drive end 202 of the third link 21 can be driven simultaneously. The leg link structure is controlled by two independent drive motors. By combining the two sets of independent motions, the leg structure can output any desired motion and trajectory within its limits, and the motion is more flexible. Furthermore, the first drive end 201 and the second drive end 202 are located at adjacent ends of a pentagon formed by the lines connecting the first pivot point 311, the second pivot point 321, the sixth pivot point 221, the first drive end 201, and the second drive end 202. Therefore, the drive mechanism of the entire leg structure can be arranged together, making the various links of the entire leg structure more lightweight and the motion more flexible and reliable.

[0047] It should be noted that the rotational connection between the connecting rods is hinged.

[0048] Among them, the second connecting rod 32, the third connecting rod 21, the fourth connecting rod 33 and the fifth connecting rod 22 are all rigid rods. During the rotation process, each connecting rod will not undergo deformation such as elongation or compression due to changes in the force, making the movement trajectory of the entire leg structure more precise and the movement more stable during the movement.

[0049] Furthermore, the first connecting rod 31 has an opposing first input end and a first output end, and the second connecting rod 32 has an opposing second input end and a second output end. The first output end and the second input end are rotatably connected to form a first rotation fulcrum 311, and the second output end is hingedly connected to the connecting member 34 to form a fourth rotation fulcrum 322. The second rotation fulcrum 321 is located between the second input end and the second output end, and the third rotation fulcrum 211 is located between the second driving end 202 and the second rotation fulcrum 321. The rotation fulcrums of each connecting rod are arranged at the ends of each connecting rod, which prevents interference between the driving arm 20 and the driven arm 30 of the leg structure during rotation, thereby expanding the range of motion and making the structure more streamlined and reliable.

[0050] In one embodiment, the first connecting rod 31 includes a first connecting portion 312 and a second connecting portion 313 that are separated from each other. The first connecting portion 312 is rotatably connected to the fifth connecting rod 22 to form the sixth rotation fulcrum 221. The second connecting portion 313 is rotatably connected to the second connecting rod 32 to form the first rotation fulcrum 311. The buffer assembly 40 includes an elastic member 41, one end of which is connected to the first connecting portion 312 and the other end of which is connected to the second connecting portion 313. When the leg structure falls from a height and is subjected to an external reaction force, the motor does not rotate, and the elastic member 41 stretches, thereby increasing the distance between the first connecting portion 312 and the second connecting portion 313 to buffer the reaction force of the ground contact end 341. This prevents the ground torque on the connecting rod 342 from acting on the output shaft of the first motor 101 or the second motor 102, thereby protecting the motors and reducing the drive failure rate of the machine leg.

[0051] Furthermore, the buffer assembly 40 also includes a guide rod 42 and a guide sleeve 43. One of the guide rod 42 and the guide sleeve 43 is located at the first connecting portion 312, and the other is located at the second connecting portion 313. The guide rod 42 is inserted into the guide sleeve 43 and slidably engages with the guide sleeve 43. Specifically, the guide rod 42 may be fixed to the first connecting portion 312, and the guide sleeve 43 may be fixed to the second connecting portion 313. Alternatively, the guide rod 42 may be fixed to the second connecting portion 313, and the guide sleeve 43 may be fixed to the first connecting portion 312. The guide sleeve 43 contains a guide groove 431 for the guide rod 42 to move in a piston-like manner. When the leg structure is subjected to a reverse force from the driven arm 30, the guide rod 42 is stretched along the guide groove 431, providing a force-deformation direction for the buffer component. This prevents bending of the buffer component, which could cause axial deformation of the first connecting rod 31 and affect the planar motion stability of the entire leg structure. In this embodiment, the guide rod 42 is fixed on the second connection part 313, and the guide sleeve 43 is fixed on the first connection part 312, so that when the ground-contacting end 341 of the robot leg is subjected to a reaction force, the guide rod 42 moves in the guide groove 431. Compared with the movement effect of the guide sleeve 43 along the guide rod 42, the guiding effect is more obvious and simple.

[0052] In one embodiment, the guide sleeve 43 is provided with a first blocking portion 432. The elastic member 41 has an initial state and a stretched state. When the elastic member 41 is in the initial state, the guide rod 42 abuts against the first blocking portion 432. When the elastic member 41 is in the stretched state, the guide rod 42 separates from the first blocking portion 432. Specifically, the first blocking portion 432 is integrally formed with the guide sleeve 43 and is a protrusion protruding from the guide groove 431, which is used to limit the movement of the guide rod 42. When the leg structure is in normal motion and the ground contact end 341 is not subjected to the instantaneous reaction force of the ground, the end of the guide rod 42 away from the second connecting portion 313 abuts against the first blocking portion 432, ensuring that the length of the leg structure does not shrink during normal motion, maintaining the length ratio of the driving arm 20 and the driven arm 30 unchanged, and making the leg structure more stable and reliable during motion. Or when the leg structure is in the air, the moment the external reaction force disappears, the elastic part 41 returns to its original shape under the action of its own elastic force, driving the guide rod 42 to abut against the first blocking part 432, so that the length of the first connecting rod 342 returns to its normal length at the moment the external reaction force disappears, and the leg structure is more stable and controllable during movement.

[0053] Furthermore, the guide sleeve 43 is provided with a second blocking portion 433, which is spaced apart from the first blocking portion 432 on the guide sleeve 43. Specifically, the distance between the first blocking portion 432 and the second blocking portion 433 corresponds to the distance the guide rod 42 can move along the guide slot 431. Accordingly, a limiting protrusion 421 is provided on the guide rod 42 to limit the contact of the limiting protrusion 421 with the second blocking portion 433 when the elastic member 41 is in the stretched state, thereby preventing the guide rod 42 from being dislodged from the guide sleeve 43. In a preferred embodiment, the limiting protrusion 421 is formed as a protrusion around the edge of the guide rod 42 that contacts the first blocking portion 432. Compared to providing the limiting protrusion 421 elsewhere on the guide rod 42, when the guide slot 431 is the same length, the guide rod 42 can move further within the guide sleeve 43, thereby increasing the tension on the elastic member 41 and providing a better buffering effect, further protecting the motor.

[0054] Furthermore, the second blocking portion 433 is the end of the guide sleeve 43 facing the first blocking portion 432, that is, the second blocking portion 433 is located at one end of the guide sleeve 43 close to the guide rod 42. Accordingly, when the length of the first connecting rod 31 remains unchanged, the first blocking portion 432 is located at the end of the guide sleeve 43, so that the guide rod 42 slides farther in the guide sleeve 43, thereby exerting greater tension on the elastic member 41, which can further enhance its buffering effect.

[0055] As a preferred embodiment, the guide sleeve 43 also includes a linear bearing 434, and the guide rod 42 passes through the linear bearing 434. The linear bearing 434 has a through hole for the guide rod 42 to pass through and slide. The guide rod 42 passes through the linear bearing 434 and extends into the guide groove 431. The linear bearing 434 is located at the end of the guide sleeve 43 and is made of metal or other rigid material, so that the guide rod 42 will not wear out during long-term use and has a longer service life.

[0056] There is one elastic member 41, elastically sleeved on the guide rod 42 or the guide sleeve 43; or, there is one elastic member 41, elastically sleeved on one side of the guide sleeve 43; or, there are not less than two elastic members 41, with at least two elastic members 41 disposed oppositely on either side of the guide sleeve 43. Specifically, when there is one elastic member 41, the elastic member 41 is a compression spring sleeved on the portion of the guide rod 42 that is positioned in the guide groove 431 of the guide sleeve 43. When the leg structure receives a reaction force, the guide rod 42 moves within the guide groove away from the first blocking portion 432, compressing the compression spring to offset the reaction force of the leg structure. This prevents the torque of the ground contact end 341 from acting on the output shaft of the first motor 101 or the second motor 102, thereby protecting the motors and reducing the drive failure rate of the machine legs. When the leg structure's connector 34 is not subjected to a large external reaction force, the compression spring recovers its deformation, driving the guide rod 42 back to its original position. This maintains the length of the first connecting rod 31 during movement, making the movement of the entire leg structure more stable. It should be noted that different tension spring strengths and materials can be selected to achieve the desired buffering effect depending on the magnitude of the reaction force, and this is not specifically limited here.

[0057] When there is only one elastic member 41 and it is arranged on one side of the guide sleeve 43, the elastic member 41 is a tension spring, one end of which is fixedly connected to the first connecting portion 312, and the other end is fixedly connected to the second connecting portion 313. The tension spring is preferably placed directly above or completely below the guide sleeve 43, so that when the leg mechanism receives a reaction force, the tension spring is more evenly stressed. Taking into account the weight of the first connecting rod 31, as well as the buffering effect and production cost, in this embodiment, as shown in the figure, the elastic member 41 is selected as a tension spring, the number of which is symmetrically arranged on both sides of the guide sleeve 43. Compared with a single tension spring or one or more tension springs, it can achieve a good buffering effect while not making the first connecting rod 31 too bulky, thereby reducing the weight of the leg structure.

[0058] In one embodiment, a first connecting hole is provided at the rotational connection between the first connecting rod 31 and the second connecting rod 32, and a first matching hole is provided at the matching position of the second connecting rod 32. The first connecting hole and the second connecting hole are aligned, and the first rotating rod passes through the first connecting hole and the second connecting hole in sequence to rotationally connect the first connecting rod 31 and the second connecting rod 32. The first rotating rod is fixed with a screw to facilitate assembly and disassembly between the connecting rods. The rotating rod serves as the first rotating fulcrum 311. The rotational connection method formed between each connecting rod is consistent. It should be noted that the first connecting rod 31 can be rotationally connected to one side of the second connecting rod 32, or it can be inserted into the interior of the second connecting rod 32. The specific rotation method can be set according to the use requirements and is not limited here.

[0059] It should be further explained that the first driving end 201 and the second driving end 202 can be arranged on the same horizontal plane, the same vertical plane, or on two different planes with different height intervals as needed. As long as their rotation axes are arranged in parallel, it is feasible. According to the different application scenarios and locations of the five-bar structure, corresponding adjustments can be made.

[0060] In one embodiment, as shown in the figure, the length between the center point of the first driving end 201 and the sixth pivot point 221 is L1, the length between the sixth pivot point 221 and the first pivot point 311 is L2, the length between the first pivot point 311 and the second pivot point 321 is L3, the length between the second pivot point 321 and the center point of the second driving end 202 is L4, the length between the center point of the second driving end 202 and the center point of the first driving end 201 is L5, and the length between the third pivot point 211 and the fifth pivot point 331 is L6. The inventors have repeatedly verified through experiments that when the lengths of the pivot points of the connecting rods differ, the working space of the leg structure and the angular space of each connecting rod also differ. Preferably, when L5 = L6, the entire leg structure can move more coordinated during movement. The lengths of the connecting rods can be set accordingly based on different working scenarios and usage requirements. The inventors have repeatedly verified through experiments that when the lengths of L1, L2, L3, L4 and L5 change, the corresponding working space and corner space of each connecting rod also change accordingly. The length of each connecting rod can be adjusted according to actual use.

[0061] It should be noted that, according to the size of the application scenario, the values ​​of L1, L2, L3, L4 and L5 can be set accordingly, and they can be scaled proportionally, or their lengths can be set to other values.

[0062] It can be understood that when the five-bar mechanism is adapted to different working scenarios by replacing connecting rods with different rod lengths, the installation efficiency of the leg structure is high, the leg structure has better adaptability and can be flexibly used in various working scenarios. There is no restriction on the rod length here.

[0063] In one embodiment, the line connecting the second pivot point 321, the third pivot point 211, the fourth pivot point 322, and the fifth pivot point 331 forms a parallelogram. That is, when the leg structure moves, the motion trajectories of the connector 34 and the third link 21 are always parallel, and one end of the third link 21 is connected to the driving member. In actual use, the motion trajectory of the connector 34 can be calculated based on the linear relationship between the servo motor rotation angle and the linkage mechanism. When the line connecting the second pivot point 321, the third pivot point 211, the fourth pivot point 322, and the fifth pivot point 331 forms a parallelogram, when the first motor 101 and the second motor 102 drive the leg structure to rotate, each link performs a regular motion within a plane. The servo motor rotation angle and the motion path of each link of the leg structure are linearly related, which makes it easier for the control system to calculate the real-time angle and position of the link during movement, making the control algorithm simpler, reducing the computer requirements when controlling the high-speed movement of the leg structure, and thus reducing control costs.

[0064] It should be noted that the second pivot point 321 is located between the first pivot point 311 and the fifth pivot point 331, and the third pivot point 211 is located between the second drive end 202 and the second pivot point 321. Compared to the second pivot point 321 being located between the third pivot point 211 and the second drive end 202, in this embodiment, placing the third pivot point 211 between the second drive end 202 and the second pivot point 321 makes the leg structure more compact and the range of motion wider.

[0065] Furthermore, the connecting member 34 extends from the fifth rotation fulcrum 331 toward the fourth rotation fulcrum 322 to form a connecting rod 342. The end of the connecting rod 342 away from the fourth rotation fulcrum 322 is a ground contact end 341, which is used to abut against the ground. According to usage needs, a soft pad or a rubber sleeve can be added to the ground contact end 341 to increase the contact area between the ground contact end 341 and the ground, so as to reduce the reaction force of the ground on it.

[0066] Since the line connecting the second rotating fulcrum 321, the third rotating fulcrum 211, the fourth rotating fulcrum 322 and the fifth rotating fulcrum 331 is a parallelogram, it can be understood that when the leg structure moves, the movement trajectory of the third connecting rod 21 is consistent with the movement trajectory of the connecting member 34. By extending the length of the connecting member 34, when the leg structure is used in the robot leg, it is equivalent to extending the length of the calf of the machine leg structure, so that the leg structure has a larger range of movement in one rotation cycle, thereby improving its speed.

[0067] It should be further explained that when the leg structure is used in other mechanical devices, the connecting member 34 includes a first rod portion and a second rod portion connected to each other. The first rod portion is rotatably connected to the second connecting rod 32 and the fourth connecting rod 33 to form a fourth rotation fulcrum 322 and a fifth rotation fulcrum 331. In this case, the second rod portion of the connecting member 34 can be a connecting rod, a straight rod, a bent rod, or a multi-jointed member, which is not limited here.

[0068] As a preferred embodiment, the fifth link 22 includes an integrally formed first section and a second section, and the first section and the second section are connected in a bent manner, that is, the fifth link 22 is not a straight rod, but a bent special-shaped rod, the first driving end 201 is arranged on the first section, and the second section is rotatably connected to the first link 31 to form a sixth rotation fulcrum 221, and the corresponding third link 21 also includes an integrally formed third section and a fourth section, and the third section and the fourth section are bent in connection, wherein the bending direction between the third section and the fourth section is consistent with the bending direction between the first section and the second section of the fifth link 22, so that when the first motor 101 and the second motor 102 respectively drive the fifth link 22 and the first link 31 to rotate in the same direction, the entire leg structure can be contracted more tightly and occupy less space. Furthermore, compared to a straight rod, the fifth link 22 is configured as a bent rod with a first section and a second section. This ensures that when the leg structure moves to any angle, the other links will not directly exert a reaction force on the connection between the fifth link 22 and the first motor 101. This reduces the reaction force exerted by the first motor 101 when driving the fifth link 22, making the rotation of the entire leg structure more flexible and reliable. Compared to a straight rod, the use of a bent rod for the third link 21 results in a smaller rotation of the driving member when the connecting member 34 rotates at the same angle, further reducing the performance requirements of the first motor 101 and saving costs.

[0069] It should be noted that the fifth connecting rod 22 can also be a curved rod, a bent rod, or any other shape, as long as its two end points are rotatably connected to the first motor 101 and the first connecting rod 31, respectively. The shape of the fifth connecting rod 22 is not specifically limited here. Correspondingly, other connecting rods can be straight rods, curved rods, bent rods, or any other shapes, and are not specifically limited here.

[0070] The drive assembly 10 also includes a housing 103, and the housing 103 has a mounting groove for the first motor 101 and the second motor 102 to be fixedly mounted. The housing, the first motor, the second motor and the third motor are integrally formed, which makes the manufacture of the entire drive assembly simpler. Moreover, the drive assembly is integrally formed, and when one of the motors in the drive assembly fails, the entire assembly can be removed and quickly replaced, which can effectively improve its maintenance efficiency. Preferably, the entire housing is a sealed housing, and the housing has a first reserved opening for the rotating shaft of the first motor to extend out, and a second reserved opening for the rotating shaft of the second motor to extend out. By adding a sleeve and a waterproof gasket that are compatible with the rotating shaft at each reserved opening, when the motor is a waterproof motor, the entire drive assembly can be completely waterproof, and the entire mechanical leg is a purely mechanical structure, which can be applied to extreme environments and underwater environments.

[0071] It should be noted that the first motor and the second motor can be single-axis motors or dual-axis motors, and can be selected according to the size of the robotic arm and specific motion requirements. In this embodiment, considering the cost of the motor and the size and cost of the entire robotic motion arm, the first motor and the second motor are single-axis motors.

[0072] In another embodiment, if Figure 2 As shown, when the first motor 101 and the second motor 102 are both single-axis motors and the leg structure is relatively large, in order to prevent the motor's rotating shaft from being damaged, the housing 103 has a first pair of side shafts with the same rotating axis as the rotating shaft of the first motor 101 on the side away from the rotating shaft of the first motor 101, and the first driving end 201 includes a first active end 2011 connected to the rotating shaft of the first motor 101 and a first connecting end 2012 connected to the first pair of side shafts, that is, the first driving end 201 of the driving arm is forked into the first active end 2011 and the first connecting end 2012 arranged at intervals, and are rotatably connected to the rotating shaft of the first motor 101 and the first pair of side shafts, respectively, thereby improving the bearing capacity of the rotating shaft of the first motor 101. When the entire leg structure is larger, the rotating shaft of the first motor is more evenly subjected to gravity, and the rotating shaft of the motor is not easily damaged when subjected to external reaction force. At the same time, the stability of the entire robotic arm structure can be improved, and the rigid reaction force of the driven arm of the robotic arm on the motor rotating shaft when it touches the ground at high speed can be reduced. The connection method of the corresponding second motor is consistent with that of the first motor, and will not be described in detail here.

[0073] In other embodiments, according to actual use requirements, the first motor, the second motor and the third motor can be dual-axis motors, which are not limited here.

[0074] Furthermore, when both the first motor and the second motor are single-axis motors, the side of the housing away from the rotating shaft of the first motor has a first pair of side shafts with the same rotation axis as the rotating shaft of the first motor, and the first driving end includes a first active end connected to the rotating shaft of the first motor and a first connecting end connected to the first pair of side shafts, that is, the first driving end of the driving arm is forked into a first active end and a first connecting end that are spaced apart and are rotatably connected to the rotating shaft of the first motor and the first pair of side shafts, respectively, thereby improving the bearing capacity of the rotating shaft of the first motor, so that when the entire robotic arm is larger, the rotating shaft of the first motor is more evenly subjected to gravity, and the rotating shaft of the motor is not easily damaged when subjected to external reaction force, while also improving the stability of the entire robotic arm structure and reducing the reaction force of the driven arm of the robotic arm on the motor shaft and rigid reaction force when it touches the ground at high speed. The corresponding connection method of the second motor is consistent with that of the first motor, and will not be elaborated here.

[0075] In another embodiment, as shown in the figure, when the buffer assembly 40 of the leg structure is arranged on the driving arm 20, the driving arm 20 includes a first connecting rod 31 and a fifth connecting rod 22, and the first driving end 201 of the first connecting rod 31 is rotatably connected to the first motor 101, and the second driving end 202 of the fifth connecting rod 22 is rotatably connected to the second motor 102. The driven arm 30 includes a second link 32, a third link 21 and a fourth link 33; the first link 31 and the second link 32 are rotatably connected to form a first rotation fulcrum 311; the third link 21 and the second link 32 are rotatably connected to form a second rotation fulcrum 321; the third link 21 and the fourth link 33 are rotatably connected to form a third rotation fulcrum 211; the second link 32 and the fourth link 33 are rotatably connected through a connecting member 34 to form a fourth rotation fulcrum 322 and a fifth rotation fulcrum 331 respectively; the second rotation fulcrum 321 is located between the first rotation fulcrum 311 and the fifth rotation fulcrum 331; the second rotation fulcrum 321, the third rotation fulcrum 211, the fourth rotation fulcrum 322, and the fifth rotation fulcrum The line connecting 331 is a quadrilateral; one end of the fifth link 22 is rotatably connected to the third link 21 to form a seventh rotating fulcrum 212, and the third rotating fulcrum 211 is located between the second rotating fulcrum 321 and the seventh rotating fulcrum 212. The other end of the fifth link 22 is a first driving end 201 for driving and connecting to the first motor 101, and the first link 31 has a second driving end 202 for driving and connecting to the second motor 102. The rotation axes of the first driving end 201 and the second driving end 202 are parallel; the line connecting the first rotating fulcrum 311, the second rotating fulcrum 321, the seventh rotating fulcrum 212, the first driving end 201 and the second driving end 202 is a pentagon, and the buffer assembly 40 is also installed on the first link 31.

[0076] Correspondingly, the fifth link 22 includes an integrally formed first section and a second section, and the first section and the second section are connected in a bending manner, that is, the fifth link 22 is not a straight rod, but a bent special-shaped rod. The first driving end 201 is arranged on the first section, and the second section is rotatably connected to the first link 31 to form a sixth rotation fulcrum 221. The corresponding first link 31 also includes an integrally formed third section and a fourth section, and the third section and the fourth section are bent in connection, wherein the bending direction between the third section and the fourth section is consistent with the bending direction between the first section and the second section of the fifth link 22, so that when the first motor 101 and the second motor 102 respectively drive the fifth link 22 and the first link 31 to rotate in the same direction, the entire leg structure can be contracted more tightly and occupy less space. Moreover, compared to a straight rod, the fifth connecting rod 22 is configured as a bent rod with a first section and a second section, so that when the leg structure moves to any angle, the other connecting rods will not directly exert a reaction force on the connection between the fifth connecting rod 22 and the first motor 101, thereby reducing the reaction force of the first motor 101 in the process of driving the fifth connecting rod 22, making the rotation of the entire leg structure more flexible and reliable. When the first connecting rod 31 is a bent rod compared to a straight rod, when the connecting member 34 rotates within the same range, the driving member rotates with a smaller amplitude, which can further reduce the performance requirements of the first motor 101 and save costs. It is easy to understand that compared with the previous embodiment, the position of the fifth connecting rod 22 in this embodiment has changed, while the other connecting rod structures and features remain unchanged.

[0077] The present invention also proposes a mechanical device, which includes a leg structure. The specific structure of the leg structure refers to the above-mentioned embodiment. Since the mechanical device adopts all the technical solutions of all the above-mentioned embodiments, it at least has all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be repeated here one by one.

[0078] The mechanical device is a unipedal or multi-pedal robot, such as a bipedal robot, a robot dog, a robot horse, etc. It can also be an underwater robot or an aerial robot, which are not limited here.

[0079] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural transformations made by using the contents of the present invention description and drawings under the inventive concept of the present invention, or direct / indirect application in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A leg structure, characterized in that: include: A drive assembly, the drive assembly comprising a first motor and a second motor; A driving arm, the driving arm having a first driving end and a second driving end, the first driving end being connected to the first motor, and the second driving end being connected to the second motor; A driven arm, the driven arm is in transmission connection with the driving arm and follows the movement of the driving arm, and the driven arm has a ground contacting end; A buffer component, the buffer component is switchable between an initial state and a deformed state and is disposed on the driving arm or the driven arm; the buffer component is used to be in the initial state when the reaction force transmitted to the driving component by the ground contact end is less than a preset reaction force; When the reaction force transmitted from the ground contact end to the driving component is greater than the preset reaction force, the device is in a deformed state to alleviate the reaction force transmitted from the ground contact end to the driving component; The buffer assembly is arranged on the driven arm, the driving arm comprises a fifth connecting rod, and the driven arm comprises a first connecting rod and a second connecting rod; The first connecting rod comprises a first connecting portion and a second connecting portion separated from each other, the first connecting portion is connected to the fifth connecting rod, and the second connecting portion is connected to the second connecting rod; The buffer assembly includes an elastic member, one end of the elastic member is connected to the first connecting portion, and the other end of the elastic member is connected to the second connecting portion; The buffer assembly further comprises a guide rod and a guide sleeve, one of the guide rod and the guide sleeve is arranged at the first connecting portion, and the other of the guide rod and the guide sleeve is arranged at the second connecting portion; the guide rod is inserted into the guide sleeve and slidably cooperates with the guide sleeve; The number of the elastic member is one, and the elastic sleeve is arranged on the guide rod or the guide sleeve; or, The number of the elastic member is one, and the elastic member is arranged on one side of the guide sleeve; or, The number of the elastic members is not less than two, and at least two of the elastic members are arranged oppositely on two sides of the guide sleeve; The drive assembly also includes a shell, which has an installation groove for installing and fixing the first motor and the second motor. A first pair of side shafts with the same rotation axis as the output shaft of the first motor are provided on the side of the shell away from the output shaft of the first motor, and the first driving end includes a first active end respectively connected to the output shaft of the first motor and a first connecting end connected to the first pair of side shafts.

2. The leg structure according to claim 1, characterized in that: The driving arm further includes a third connecting rod, a first driving end of the third connecting rod is rotatably connected to the first motor, a second driving end of the fifth connecting rod is rotatably connected to the second motor, and the driven arm further includes a fourth connecting rod; The first connecting rod and the second connecting rod are rotatably connected to form a first rotation fulcrum; The third connecting rod is rotatably connected to the second connecting rod to form a second rotation fulcrum; The third connecting rod and the fourth connecting rod are rotatably connected to form a third rotation fulcrum; The second connecting rod and the fourth connecting rod are rotatably connected through a connecting member, and form a fourth rotation fulcrum and a fifth rotation fulcrum respectively; The connecting line of the second rotation fulcrum, the third rotation fulcrum, the fourth rotation fulcrum and the fifth rotation fulcrum forms a quadrilateral; The connecting line of the first rotation fulcrum, the second rotation fulcrum, the seventh rotation fulcrum, the first driving end and the second driving end is a pentagon; The first connecting rod is rotatably connected to the fifth connecting rod to form a sixth rotation fulcrum; the rotation axes of the first motor and the second motor are arranged in parallel; The buffer assembly is mounted on the first connecting rod.

3. The leg structure according to claim 2, characterized in that: The connecting line of the second rotation fulcrum, the third rotation fulcrum, the fourth rotation fulcrum and the fifth rotation fulcrum forms a parallelogram.

4. The leg structure according to claim 2, characterized in that: The guide sleeve is provided with a first blocking portion, and the elastic member has an initial state and a stretched state. When the elastic member is in the initial state, the guide rod abuts against the first blocking portion, and when the elastic member is in the stretched state, the guide rod is separated from the first blocking portion.

5. The leg structure according to claim 4, characterized in that: The guide sleeve is provided with a second blocking portion, and the second blocking portion is spaced apart from the first blocking portion on the guide sleeve; a limiting protrusion is provided on the guide rod, and when the elastic member is in the stretched state, the limiting protrusion is limitedly abutted against the second blocking portion to limit the guide rod from coming out of the guide sleeve.

6. The leg structure according to claim 5, characterized in that: The second blocking portion is an end portion of the guide sleeve facing the first blocking portion.

7. The leg structure according to claim 6, characterized in that: The guide sleeve includes a linear bearing arranged inside, and the guide rod is passed through the linear bearing.

8. The leg structure according to claim 2, characterized in that: The connecting member is a connecting rod, or the connecting member includes a first rod portion and a second rod portion connected to each other, and the first rod portion is rotatably connected to the second connecting rod and the fourth connecting rod to form the fourth rotation fulcrum and the fifth rotation fulcrum.

9. The leg structure according to claim 1, characterized in that: A second pair of side shafts having the same rotation axis as the output shaft of the second motor is arranged on one side of the shell away from the output shaft of the second motor, and the second driving end includes a second active end respectively connected to the output shaft of the second motor and a second connecting end connected to the second pair of side shafts.

10. A mechanical device, characterized in that: Comprising the leg structure according to any one of claims 1 to 9.

11. The mechanical device according to claim 10, characterized in that The mechanical device is a monopedal or multi-pedal robot.

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