Four-foot obstacle crossing robot based on coupling crank rocker and parallelogram mechanism

Abstract

The invention provides a four-footed obstacle crossing robot based on a coupling crank rocker and a parallelogram mechanism, and relates to the technical field of robots, the four-footed obstacle crossing robot comprises a rack and a driving mechanism; the mechanical legs are symmetrically arranged on the two sides of the rack, and the number proportion of the driving mechanisms to the mechanical legs is 1: 2; each mechanical leg comprises a crank rocker mechanism and a supporting mechanism which are connected in sequence; the driving mechanism is connected with the crank rocker mechanism and used for driving the crank rocker mechanism to move so as to drive the supporting mechanism to do reciprocating lifting swing. The crank rocker mechanism comprises a crank; the cranks located on the same side of the machine frame rotate in the same plane, and the sum of the included angles formed by the extension lines of the cranks of any two adjacent mechanical legs on the same side of the machine frame and the advancing direction of the four-foot obstacle crossing robot is constantly 180 degrees. The invention has the beneficial effects of high flexibility, good bearing capacity and strong environmental adaptability.

Description

Technical Field

[0001] The present invention relates to the field of robot technology, in particular to a quadruped obstacle-crossing robot based on a coupled crank rocker and a parallelogram mechanism. Background Art

[0002] The development of traditional wheeled robots has seen the emergence of bipedal, quadrupedal, and hexapodal wheeled robots. Bipedal wheeled robots are more capable of avoiding obstacles than hexapodal wheeled robots, but their obstacle-crossing capabilities are significantly inferior to those of crawling robots. Their bipedal propulsion also means they suffer from poor balance and load-carrying capacity. Furthermore, bipedal obstacle-crossing robots, due to their high center of gravity and small support surface, are prone to losing balance and falling when navigating rough terrain or encountering external forces. This can lead to mission interruption at best and mission failure at worst. Hexapod wheeled robots offer greater load-carrying capacity and stability than bipedal robots, but their six mechanical legs make control more challenging. When navigating complex terrain, even the slightest misalignment between the mechanical legs can cause a fall. In narrow passages or cluttered spaces, the multiple mechanical legs can easily interfere with each other and trip over each other. Furthermore, the robot's large footprint severely limits its application in confined environments.

[0003] Chinese patent document CN110371212A discloses an obstacle-crossing robot and its obstacle-crossing method, including a structural module, which includes a fuselage and three sets of walking mechanisms arranged in sequence along the length direction of the fuselage, each of the three walking mechanisms includes two obstacle-crossing devices symmetrically arranged on both sides of the fuselage, the obstacle-crossing devices include a first drive device arranged on the fuselage, a leg bracket connected to the first drive device, a drive wheel arranged at the other end of the leg bracket, and a second drive device connected to the axle of the drive wheel and providing power for it; a sensing module, which is arranged on the fuselage; a control system, which is electrically connected to the sensing module and the first drive device and the second drive device of the three walking mechanisms, and is used to receive information collected by the sensing module and control the working conditions of the three walking mechanisms based on the collected information.

[0004] However, the obstacle-crossing robot disclosed in the above patent still has the following defects: First, the mechanical legs adopt a complex multi-joint structure, which makes the design of the control algorithm extremely difficult, greatly increasing the difficulty of control. At the same time, the complex mechanical structure and high-precision component requirements have pushed up the manufacturing cost. Moreover, when faced with real-life scenarios such as long-distance load transportation and complex terrain obstacle crossing, traditional obstacle-crossing robots are difficult to fully exert their effectiveness due to the limitations of power performance and obstacle crossing strategies. Second, multi-degree-of-freedom obstacle-crossing robots have many joints, complex control algorithms, and high requirements for processor calculations and data transmission. Slight deviations in the algorithm will lead to movement disorders. During manufacturing, a large number of precision components such as motors and sensors are required, and the processing and assembly processes are rigorous, resulting in high R&D costs. Multiple joints consume energy at the same time during movement, requiring frequent charging, and the increased battery weight forms a vicious cycle. In addition, complex software and hardware make maintenance more difficult. Summary of the Invention

[0005] The present invention overcomes the shortcomings of the prior art and provides a quadruped obstacle-crossing robot based on a coupled crank rocker and a parallelogram mechanism, which has the advantages of high flexibility, good carrying capacity and strong environmental adaptability.

[0006] In order to solve the above technical problems, the present invention is achieved through the following technical solutions:

[0007] A quadruped obstacle-crossing robot based on a coupled crank rocker and parallelogram mechanism comprises a frame;

[0008] a driving mechanism rotatably connected to the frame;

[0009] The mechanical legs are symmetrically arranged on both sides of the frame, wherein the ratio of the number of the driving mechanisms to the number of the mechanical legs is 1:2; the mechanical legs include a crank-rocker mechanism and a support mechanism connected in sequence; the driving mechanism is connected to the crank-rocker mechanism to drive the crank-rocker mechanism to move, thereby driving the support mechanism to perform reciprocating lifting and swinging;

[0010] The crank rocker mechanism includes a crank, which is connected to the drive mechanism; multiple cranks located on the same side of the frame rotate in the same plane, and the sum of the angles formed by the extension lines of the cranks of any two adjacent mechanical legs on the same side of the frame and the forward direction of the quadruped obstacle-crossing robot is constant at 180°.

[0011] Furthermore, a first connecting rod and a second connecting rod are used to connect adjacent drive mechanisms; the front ends of the first connecting rod and the second connecting rod are both hinged to the drive mechanism located in the front, and the rear ends thereof are both hinged to the drive mechanism located in the rear; and the first connecting rod and the second connecting rod are respectively located on the left and right sides of the connected drive mechanism;

[0012] The driving mechanism includes an upper connecting rod and a lower connecting rod that are parallel to each other and of equal length, and a left connecting rod and a right connecting rod that are parallel to each other and of equal length; the upper connecting rod, the left connecting rod, the lower connecting rod and the right connecting rod are hinged end to end in sequence to form a planar four-bar mechanism;

[0013] When viewed from the side, the first connecting rod, the driving mechanism located in the front, the second connecting rod and the driving mechanism located in the rear together form a parallelogram mechanism.

[0014] Furthermore, a right linkage rod is hinged on one side of the upper link, and an end of the right linkage rod is connected to a crank of one side of the mechanical leg through a first connecting key;

[0015] A left linkage rod is hinged on one side of the lower link, and an end of the left linkage rod is connected to the crank of the mechanical leg on the other side through a second connecting key.

[0016] Furthermore, the middle regions of the first connecting key and the second connecting key have cylindrical cross-sections;

[0017] The frame is provided with circular holes which are matched with the cylindrical cross-sections of the middle sections of the first connecting key and the second connecting key, and the first connecting key and the second connecting key are rotatably inserted into the corresponding circular holes.

[0018] Furthermore, the crank-rocker mechanism further includes a first component and a second component;

[0019] One end of the first member is hinged to the frame, and the other end thereof is hinged to one end of the second member;

[0020] The other end of the second member is hinged to the crank.

[0021] Furthermore, the support mechanism includes a third component and a fourth component; the upper end of the third component is hinged to the hinge point between the first component and the second component; the upper end of the fourth component is hinged to the hinge point between the second component and the crank; the lower ends of the third component and the fourth component are jointly hinged to a foot block.

[0022] Furthermore, the lower end surface of the foot block is a planar structure.

[0023] Furthermore, the motion phase of any mechanical leg located on one side of the frame is the same as the motion phase of the mechanical leg located on the opposite side of the frame and adjacent to it along the forward direction of the robot.

[0024] Furthermore, the frame is a rectangular frame structure, with an open area formed in the middle thereof for accommodating the rotation space of the driving mechanism.

[0025] Furthermore, the left linkage rod and the right linkage rod are both located within the horizontal projection outline of the frame.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] 1. It has many advantages such as flexible movement ability, good carrying capacity, high environmental adaptability and simple control, and can be widely used in many fields.

[0028] 2. The crank rocker mechanism is used in the design of the mechanical legs. This design can realize multiple movement modes of the mechanical legs, such as swinging and lifting, so that the robot can flexibly adjust obstacle crossing and step size.

[0029] 3. Four sets of identical mechanical legs are set up on the frame, so that when the obstacle-crossing robot carries a large weight, the total weight of the object can be distributed to each mechanical leg and it can walk stably.

[0030] 4. The length parameters of the cranks and rockers on the mechanical legs can be adjusted, so the robot can achieve leg movements at different heights and angles, allowing it to easily cross obstacles, climb slopes or walk on rugged terrain.

[0031] 5. A parallelogram mechanism is used in the design of the driving mechanism. The four legs are connected to the four corners of the parallelogram in sequence, which can couple the degrees of freedom of the four legs. Finally, the quadruped obstacle-crossing robot has only a single degree of freedom. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The accompanying drawings are used to provide a further understanding of the present invention and are used to explain the present invention together with the embodiments of the present invention, but do not constitute a limitation of the present invention. In the accompanying drawings:

[0033] Figure 1 This is a side view of the quadruped obstacle-crossing robot;

[0034] Figure 2 It is a three-dimensional diagram of a quadruped obstacle-crossing robot;

[0035] Figure 3 This is a top view of the quadruped obstacle-crossing robot;

[0036] Figure 4 is a schematic diagram of adjacent drive mechanisms and a first connecting rod, a second connecting rod, a right linkage rod, and a left linkage rod;

[0037] Figure 5 It is a schematic diagram of the state in which the driving mechanism is connected to the frame;

[0038] Figure 6 is a schematic diagram of the connection state between adjacent driving mechanisms and the first connecting rod and the second connecting rod;

[0039] Figure 7 It is a structural diagram of the rack;

[0040] Figure 8 This is a schematic diagram of the structure of the mechanical leg;

[0041] Figure 9 is a schematic structural diagram of the first connecting bond;

[0042] Figure 10 This is a diagram of a four-legged obstacle-crossing robot walking. Figure 1 , at this time, the left 1 and right 2 mechanical legs are in the standing state, and the left 2 and right 1 mechanical legs are in the forward swinging state;

[0043] Figure 11 This is a diagram of a four-legged obstacle-crossing robot walking. Figure 2 At this time, the mechanical legs of left 2 and right 1 are in a standing state, and the mechanical legs of left 1 and right 2 are in a forward swinging state.

[0044] In the picture:

[0045] 1. Frame; 101. Round hole; 2. Driving mechanism; 201. Upper connecting rod; 202. Lower connecting rod; 203. Left connecting rod; 204. Right connecting rod; 3. Mechanical leg; 301. Crank rocker mechanism; 3011. Crank; 3012. First component; 3013. Second component; 302. Support mechanism; 3021. Third component; 3022. Fourth component; 4. First connecting rod; 5. Second connecting rod; 6. Right linkage rod; 7. First connecting key; 8. Left linkage rod; 9. Second connecting key; 10. Foot block. DETAILED DESCRIPTION

[0046] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0047] like Figures 1 to 9 As shown, the present invention seeks protection for a quadruped obstacle-crossing robot based on a coupled crank rocker and a parallelogram mechanism. The quadruped obstacle-crossing robot is mainly composed of a frame 1, a drive mechanism 2, and mechanical legs 3, and the obstacle-crossing function is achieved through the coordinated work of various parts.

[0048] Specifically, if Figure 3 、 Figure 5 as well as Figure 7 As shown, the frame 1 is a rectangular frame structure with an open area formed in the middle. The function of the open area is to provide a rotation space for the driving mechanism 2 to ensure that the driving mechanism 2 will not be interfered by the frame 1 during the movement.

[0049] The drive mechanism 2 is rotatably connected to the frame 1. The ratio of the number of drive mechanisms 2 to the number of mechanical legs 3 is 1:2. Since this embodiment is a quadruped obstacle-climbing robot, there are four mechanical legs 3 and two drive mechanisms 2, which meets the proportional constraint requirement. One drive mechanism 2 synchronously drives the mechanical legs 3 on both sides to move.

[0050] The drive mechanism 2 includes an upper link 201 and a lower link 202, which are parallel and of equal length, as well as a left link 203 and a right link 204, which are parallel and of equal length. The upper link 201, the left link 203, the lower link 202, and the right link 204 are hinged end-to-end to form a planar four-bar linkage. It also includes a first link 4 and a second link 5 for connecting adjacent drive mechanisms 2. The front ends of the first and second links 4 and 5 are hinged to the drive mechanism 2 located in front, and their rear ends are hinged to the drive mechanism 2 located in the rear. The first and second links 4 and 5 are respectively located on the left and right sides of the connected drive mechanism 2. When viewed from the side, the first link 4, the drive mechanism 2 located in the front, the second link 5, and the drive mechanism 2 located in the rear together form a parallelogram. By connecting the four mechanical legs 3 to the four corners of this parallelogram, the degrees of freedom of the four mechanical legs 3 can be coupled, resulting in a quadruped obstacle-climbing robot with only a single degree of freedom.

[0051] One side of the upper connecting rod 201 is hinged with a right linkage rod 6, the end of which is connected to the crank 3011 of one side of the mechanical leg 3 via a first connecting key 7; one side of the lower connecting rod 202 is hinged with a left linkage rod 8, the end of which is connected to the crank 3011 of the other side of the mechanical leg 3 via a second connecting key 9. The middle section of the first connecting key 7 and the second connecting key 9 has a cylindrical cross-section. The frame 1 is provided with a circular hole 101 that is compatible with the middle section cylindrical cross-section of the first connecting key 7 and the second connecting key 9. The first connecting key 7 and the second connecting key 9 are rotatably inserted into the corresponding circular hole 101. This design enables the drive mechanism 2 to stably drive the mechanical leg 3 to move and is not prone to slipping. At the same time, the left linkage rod 8 and the right linkage rod 6 are both located within the horizontal projection outline of the frame 1 to avoid collision with external objects during movement. The drive mechanism 2 is coaxially connected to a micro motor at the first connecting key 7 or the second connecting key 9 for driving rotation.

[0052] The mechanical legs 3 are symmetrically arranged on both sides of the frame 1 , and the mechanical legs 3 include a crank rocker mechanism 301 and a support mechanism 302 connected in sequence.

[0053] The crank-rocker mechanism 301 includes a crank 3011, which is connected to the drive mechanism 2. The multiple cranks on the same side of the frame 1 rotate in the same plane. That is, the rotation planes of the cranks on both sides of the frame 1 are parallel. This allows the robot legs 3 to move in a fixed direction. Therefore, the robot can only move in a straight line and cannot turn, making it less prone to lateral deviation.

[0054] like Figure 1 As shown, the sum of the angles between the extension lines of the cranks of any two adjacent mechanical legs 3 on the same side of the frame 1 and the forward direction of the quadruped obstacle robot is constant at 180°. That is, if the angle between the extension line of one mechanical leg 3 and the forward direction of the quadruped obstacle robot is set to α, and the angle between the extension line of the other mechanical leg 3 and the forward direction of the quadruped obstacle robot is set to β, then α+β=180°. Figure 10 as well as Figure 11 Analysis, in Figure 10 In the figure, the crank of the left first mechanical leg 3 is vertically downward, and the angle α formed with the forward direction of the quadruped obstacle climbing robot is 90°. The crank of the left second mechanical leg 3 is vertically upward, and the angle β formed with the forward direction of the quadruped obstacle climbing robot is 90°, satisfying α+β=180°. During the walking process, the crank of the left first mechanical leg 3 and the crank of the left second mechanical leg 3 always remain parallel or collinear. The purpose of the above setting is to

[0055] like Figure 10 As shown, when the right 1 mechanical leg 3 and the left 2 mechanical leg 3 swing forward, the left 1 mechanical leg 3 and the right 2 mechanical leg 3 play a supporting role, and the center of gravity of the robot is located on the line connecting the left 1 mechanical leg 3 and the right 2 mechanical leg 3. When the right 1 mechanical leg 3 and the left 2 mechanical leg 3 step forward, the left 1 mechanical leg 3 and the right 2 mechanical leg 3 will drive the corresponding joints to move the body forward, causing the center of gravity of the model to lean forward, just making the center of gravity within the diagonal stable area of the left 1 mechanical leg 3 and the right 2 mechanical leg 3; when the body moves into place, the right 1 mechanical leg 3 and the left 2 mechanical leg 3 are immediately lowered, and the four legs touch the ground to maintain a balanced standing state. Then, enter the Figure 11 As shown, the left and right mechanical legs 3 are lifted and step forward, with the right and left mechanical legs 3 acting as support. The right and left mechanical legs 3 drive the joints to move the body forward, and the model's center of gravity begins to tilt forward, precisely within the diagonal stability zone of the right and left mechanical legs 3. The left and right mechanical legs 3 are immediately lowered, with all four legs resting on the ground to maintain balance, thus completing the entire walking cycle.

[0056] In this embodiment, the crank-rocker mechanism 301 further includes a first member 3012 and a second member 3013. One end of the first member 3012 is hinged to the frame 1, and the other end is hinged to one end of the second member 3013. The other end of the second member 3013 is hinged to the crank. The support mechanism 302 includes a third member 3021 and a fourth member 3022. The upper end of the third member 3021 is hinged to the hinge point between the first member 3012 and the second member 3013. The upper end of the fourth member 3022 is hinged to the hinge point between the second member 3013 and the crank 3011. The lower ends of the third and fourth members 3021 and 3022 are hinged to a foot block 10. The lower end surface of the foot block 10 is a flat structure. This structural design helps the robot maintain stability during walking and obstacle traversal.

[0057] Combine Figure 1 、 Figure 2 、 Figure 10 as well as Figure 11 It can be seen that the motion phase of any mechanical leg 3 located on one side of the frame 1 is the same as the motion phase of the mechanical leg 3 located on the opposite side of the frame 1 and adjacent to it along the forward direction of the robot, that is, the motion phase of the left 1 mechanical leg 3 is the same as the motion phase of the right 2 mechanical leg 3, that is, the motion phase of the left 2 mechanical leg 3 is the same as the motion phase of the right 1 mechanical leg 3. Such a phase setting helps the robot achieve stable walking and obstacle crossing.

[0058] The operating principle of this quadruped obstacle-climbing robot is as follows: when the drive mechanism 2 begins to operate, the planar four-bar linkage within the drive mechanism 2 begins to move, causing the right and left linkage rods 6 and 8 to move. This movement is then transmitted to the crank 3011 of the crank-rocker mechanism 301 via the first and second connecting keys 7 and 9, causing the crank 3011 to rotate within the same plane. The rotation of the crank 3011 drives the crank-rocker mechanism 301, which in turn drives the support mechanism 302 to lift and swing back and forth, thereby causing the footrest 10 to lift and swing back and forth, thus enabling the robot to walk and overcome obstacles. During the robot's motion, the parallelogram mechanism formed by the first and second connecting rods 4 and 5 connecting adjacent drive mechanisms 2 ensures the coordinated motion between adjacent drive mechanisms 2, making the entire robot's motion more stable and efficient.

[0059] The frame 1 of the present invention incorporates four sets of structurally identical mechanical legs 3. When the robot is carrying a heavy object, these four sets of legs 3 evenly distribute the object's weight, preventing excessive pressure on any single leg. Furthermore, this unique structural design ensures the robot maintains excellent stability during movement, allowing it to navigate complex terrain and heavy loads with unwavering confidence. This effectively improves its obstacle-crossing capabilities and payload efficiency in practical applications.

[0060] In practical applications, by flexibly adjusting parameters such as the length and angle of the crank 3011 and rocker, the robot can achieve leg movements at varying heights and angles. This feature enables the robot to excel in complex terrain: whether traversing obstacles of varying heights or navigating rugged slopes, it maintains a stable and efficient walking posture. This highly adaptive design enables the robot to demonstrate strong adaptability in diverse environments and meet the demands of complex operations.

[0061] Finally, it should be noted that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent replacements for some of the technical features therein. However, any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A quadruped obstacle-climbing robot based on a coupled crank rocker and parallelogram mechanism, characterized by: Including rack; a driving mechanism rotatably connected to the frame; The mechanical legs are symmetrically arranged on both sides of the frame, wherein the ratio of the number of the driving mechanisms to the number of the mechanical legs is 1:2; the mechanical legs include a crank-rocker mechanism and a support mechanism connected in sequence; the driving mechanism is connected to the crank-rocker mechanism to drive the crank-rocker mechanism to move, thereby driving the support mechanism to perform reciprocating lifting and swinging; The crank rocker mechanism includes a crank, which is connected to the drive mechanism; multiple cranks located on the same side of the frame rotate in the same plane, and the sum of the angles formed by the extension lines of the cranks of any two adjacent mechanical legs on the same side of the frame and the forward direction of the quadruped obstacle-crossing robot is constant at 180°.

2. The quadruped obstacle-crossing robot based on a coupled crank rocker and parallelogram mechanism according to claim 1, characterized in that: a first connecting rod and a second connecting rod for connecting adjacent drive mechanisms; the front ends of the first connecting rod and the second connecting rod are both hinged to the drive mechanism located in the front, and the rear ends of the first connecting rod and the second connecting rod are both hinged to the drive mechanism located in the rear; and the first connecting rod and the second connecting rod are respectively located on the left and right sides of the connected drive mechanism; The driving mechanism includes an upper connecting rod and a lower connecting rod that are parallel to each other and of equal length, and a left connecting rod and a right connecting rod that are parallel to each other and of equal length; the upper connecting rod, the left connecting rod, the lower connecting rod and the right connecting rod are hinged end to end in sequence to form a planar four-bar mechanism; When viewed from the side, the first connecting rod, the driving mechanism located in the front, the second connecting rod and the driving mechanism located in the rear together form a parallelogram mechanism.

3. The quadruped obstacle-crossing robot based on a coupled crank rocker and parallelogram mechanism according to claim 2, characterized in that: A right linkage rod is hinged to one side of the upper link, and an end of the right linkage rod is connected to a crank of one side of the mechanical leg through a first connecting key; A left linkage rod is hinged on one side of the lower link, and an end of the left linkage rod is connected to the crank of the mechanical leg on the other side through a second connecting key.

4. The quadruped obstacle-crossing robot based on a coupled crank rocker and parallelogram mechanism according to claim 3, characterized in that: The middle regions of the first connecting key and the second connecting key have cylindrical cross-sections; The frame is provided with circular holes which are matched with the cylindrical cross-sections of the middle sections of the first connecting key and the second connecting key, and the first connecting key and the second connecting key are rotatably inserted into the corresponding circular holes.

5. The quadruped obstacle-crossing robot based on a coupled crank rocker and parallelogram mechanism according to any one of claims 1 to 4, characterized in that: The crank-rocker mechanism further includes a first component and a second component; One end of the first member is hinged to the frame, and the other end thereof is hinged to one end of the second member; The other end of the second member is hinged to the crank.

6. The quadruped obstacle-crossing robot based on a coupled crank rocker and parallelogram mechanism according to claim 5, characterized in that: The support mechanism includes a third component and a fourth component; the upper end of the third component is hinged to the hinge point between the first component and the second component; the upper end of the fourth component is hinged to the hinge point between the second component and the crank; the lower ends of the third component and the fourth component are jointly hinged to a footrest.

7. The quadruped obstacle-crossing robot based on a coupled crank rocker and parallelogram mechanism according to claim 6, characterized in that: The lower end surface of the footrest is a plane structure.

8. The quadruped obstacle-crossing robot based on a coupled crank rocker and parallelogram mechanism according to claim 6, characterized in that: The motion phase of any mechanical leg located on one side of the frame is the same as the motion phase of the mechanical leg located on the opposite side of the frame and adjacent to it along the forward direction of the robot.

9. The quadruped obstacle-crossing robot based on a coupled crank rocker and parallelogram mechanism according to claim 1, characterized in that: The frame is a rectangular frame structure, wherein an open area is formed in the middle thereof for accommodating the rotation space of the driving mechanism.

10. The quadruped obstacle-crossing robot based on a coupled crank rocker and parallelogram mechanism according to claim 3, characterized in that: The left linkage rod and the right linkage rod are both located within the horizontal projection outline of the frame.

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