Humanoid robot structure with balance folding and unfolding parasitic mechanism

Abstract

The invention discloses a humanoid robot structure with a balance folding and unfolding parasitic mechanism. The humanoid robot structure comprises a head, arm parts, a trunk, buttocks, legs and feet. The robot is characterized in that the buttocks and the legs are combined through double X-shaped parasitic branch chains, the two X-shaped branch chains are arranged in parallel, electric drive modules are arranged in the centers of the X-shaped branch chains respectively, and the axis is staggered to avoid the singular point problem. The electric drive module drives the branch chains to open and close synchronously, folding and unfolding actions are achieved, and the movement range can reach 360 degrees. A 10-degree inclined included angle is formed between the legs and the horizontal plane, front-back and left-right self-balance is achieved in cooperation with the crotch telescopic capacity, and the motor driving torque and dependence on an algorithm are remarkably reduced. The feet are connected with the soles through the electric drive modules to adapt to complex terrains. The problem that a traditional folding and unfolding mechanism is stuck or out of control at a singular point is solved, the dynamic stability and running capacity of the robot are improved, and the stepping distance can reach four times that of a common design.

Description

Technical Field

[0001] This invention relates to the field of robot manufacturing technology, and more specifically, to a humanoid robot structure with a balanced folding parasitic mechanism. Background Technology

[0002] A serial mechanism humanoid robot refers to a robot whose limbs (such as arms and legs) use a "sequentially connected" linkage and joint structure (similar to the connection of bones and joints in human limbs). That is, the output of one joint is directly connected to the input of the next, forming a chain structure. This structure is widely used in humanoid robots and features high mobility and a large workspace. However, it also has drawbacks: a typical serial mechanism bipedal robot requires controlling a total of eight motors (four motors per leg, two for forward / backward balance and two for left / right balance) to achieve balance in both directions. This balance is achieved through algorithms, which are highly sophisticated. Compared to parallel mechanisms, it also suffers from lower rigidity, larger error accumulation, higher energy consumption, and poorer dynamic stability.

[0003] Self-balancing of robots can be achieved through the vertically symmetrical arrangement of deployment mechanisms, or horizontally symmetrical arrangement. However, deployment mechanisms, especially parasitic deployment mechanisms, also have significant limitations. For example, due to the large number of links in a deployment mechanism, multiple links may become collinear in one or more poses within a relatively small working range. This can lead to mechanism singularities, causing sudden increases or decreases in the degrees of freedom, making the mechanism's motion unpredictable, and resulting in jamming or underactuated loss of control. To avoid these singular poses, the range of motion in a particular degree of freedom of a multi-degree-of-freedom deployment mechanism is significantly reduced. Summary of the Invention

[0004] To address the shortcomings in the prior art, this invention provides a balanced folding parasitic mechanism humanoid robot structure to solve the problem of humanoid robots getting stuck or losing control due to underactuation when using the folding mechanism to pass through singularities, thereby expanding the range of motion of the folding mechanism.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] The present invention discloses a humanoid robot structure with a balanced folding and unfolding parasitic mechanism, comprising a head, arms, torso, hips, legs, and feet. The head is connected to the upper part of the torso, the upper part of the torso has a shoulder, the shoulder is connected to the arms, the lower part of the torso is connected to the hips, the two sides of the hips are connected to the legs, and the lower part of the legs is connected to the feet. The hips and legs are provided with a folding and unfolding mechanism.

[0007] The folding mechanism employs a double-X parasitic branch combination. The specific positions and connections of the double-X parasitic branches are as follows: The first X parasitic branch consists of the first, second, third, fourth, fifth, and sixth connecting rods; the second X parasitic branch consists of the seventh, eighth, ninth, tenth, eleventh, and twelfth connecting rods; the first and second X parasitic branches have identical external dimensions, and the planes on which the first and second X parasitic branches are located are parallel to each other; electric drive modules are respectively installed at the center of the first and second X parasitic branches, and the axes of these two electric drive modules are not on the same straight line;

[0008] The outer shell of the electric drive module of one X-shaped parasitic branch of the hip folding mechanism is fixed to the torso. The two ends of the hip folding mechanism are connected to the upper end of the leg support plate through the electric drive module. The lower end of the leg support plate is connected to the center of one of the X-shaped parasitic branches of the leg folding mechanism through the electric drive module. The lower end of the hip folding mechanism is connected to the foot.

[0009] The electric drive module is externally a square frame with fixing holes on four sides and a shaft hole at the center of each side. An electric motor is fixed inside the square frame, and the motor's rotating shaft passes through the shaft hole and extends out of the square frame.

[0010] The legs are not perpendicular to the horizontal plane; the upper part of the legs leans outward, and the lower part leans inward.

[0011] The lower part of the foot is connected to the sole of the foot via an electric drive module.

[0012] The shoulder and head are connected by an electric drive module. The housing of the electric drive module is fixed below the shoulder, and the rotating shaft of the electric drive module is fixedly connected to the head.

[0013] The present invention has the following beneficial effects:

[0014] 1. Rotary telescopic balancing parasitic mechanism

[0015] Application in the hips: It enables the left and right legs to rotate around the hips and extend and retract in all directions, achieves horizontal gravity self-balancing, and significantly reduces the motor driving torque for hip rotation and extension movements.

[0016] Leg applications: Achieve gravity self-balancing in the vertical direction, significantly reducing the motor drive torque for robot leg lifting movements.

[0017] Advantages: Unlike the previous design that used an X-shaped parasitic branch and a series of multi-degree-of-freedom combinations, this design does not have a sudden change in degrees of freedom when the mechanism is singular, and the rotational range can be greatly increased to 360°. This solves the problems of sudden increase in degrees of freedom, under-drive loss of control, shaking and jamming when the original design is singular, while the rotational range of the original design is only within 90°.

[0018] 2. Structurally possessing or more easily achieving self-balancing capabilities.

[0019] Front-back balance: The robot adopts a balanced folding parasitic mechanism linkage, which has the ability to keep the output and input components structurally parallel, so that the robot's hips and feet are parallel. By appropriately lengthening the feet, the entire torso can achieve front-back horizontal balance on a level ground, reducing the requirements for the algorithm.

[0020] Left-right balance: The hips and legs have a 10-degree tilt angle to form an inverted V-shape. By tilting the legs and extending and retracting the hips to the left and right, the position of the feet on the ground can be easily controlled to be on the vertical projection point of the robot's total center of gravity, thus achieving left-right horizontal balance. Whether standing on two legs or supporting on one leg, the balance can be easily and dynamically adjusted by the two motors in the hips.

[0021] 3. The robot's running ability is significantly improved: It has the ability to extend and extend its legs over a long distance with its hips, and the actual running stride distance can be up to 4 times that of a normal stride. When running, the feet do not necessarily need to be significantly longer, and the torque generated by the body's center of gravity can cancel each other out, which is conducive to achieving dynamic balance when running. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the humanoid robot structure of the balanced unfolding parasitic mechanism described in this invention.

[0023] Figure 2 This is a schematic diagram of the structure of the double X-shaped parasitic branch described in this invention. In the diagram, red represents one X-shaped parasitic branch and blue represents the other X-shaped parasitic branch.

[0024] Figure 3 This is an enlarged structural view of the double X-shaped parasitic branches on the legs of the humanoid robot structure of the balanced folding parasitic mechanism described in this invention.

[0025] Figure 4 This is an independent view of the double X-shaped parasitic branch of the leg of the humanoid robot structure of the balanced folding parasitic mechanism described in this invention.

[0026] Figure 5 This is a structural diagram of the electric drive module.

[0027] Figure 6 This is a schematic diagram of the contraction of the double X-shaped parasitic branch in the buttocks.

[0028] Figure 7 This is a schematic diagram of the structure of the double X-shaped parasitic branches of the buttocks after unfolding.

[0029] Figure 8 Another view of the humanoid robot structure of the balanced unfolding parasitic mechanism described in this invention.

[0030] The components in the diagram are labeled as follows: Head 1, Arm 2, Hips 3, Leg 4, Foot 5, Torso 6, First Link 7, Second Link 8, Third Link 9, Fourth Link 10, Fifth Link 11, Sixth Link 12, Seventh Link 13, Eighth Link 14, Ninth Link 15, Tenth Link 16, Eleventh Link 17, Twelfth Link 18, Connecting Link 19, Drive Link 20, Bearing 21, Electric Motor 22, Shoulder 23, Leg Support Plate 24, Cross Roller Bearing 25, Square Frame 26, Electric Motor 27. Detailed Implementation

[0031] The technical solution of the present invention will be described in further detail below with reference to the accompanying drawings.

[0032] The humanoid robot structure of the balanced folding parasitic mechanism described in this invention is mainly composed of a head 1, an arm 2, a torso 6, a hip 3, a leg 4, and a foot 5. The head 1 is connected to the shoulder 23 via an electric drive module. The outer shell of the electric drive module is fixed below the shoulder 23. The rotation shaft of the electric drive module is fixedly connected to the head 1. By controlling the electric drive module, the head can be rotated.

[0033] The electric drive module is externally a square frame 26. The square frame 26 has fixing holes on its four sides and a shaft-through hole at the center of each of the four sides. An electric motor 27 is fixed inside the square frame 26, and the rotating shaft of the electric motor 27 extends out of the square frame through the shaft-through hole. The fixing holes are arranged in an array, allowing the electric drive module to be fixed to other components by passing bolts through the fixing holes and engaging nuts or threaded holes.

[0034] The most crucial aspect of this invention lies in the folding and unfolding mechanism used in the buttocks and legs, both of which employ a combination of double X-shaped parasitic branches.

[0035] The specific structure of the double-X type parasitic branch combination is as follows: Figure 2As shown, the red line represents the first X-type parasitic branch; the blue line represents the second X-type parasitic branch. The first X-type parasitic branch consists of the first link 7, the second link 8, the third link 9, the fourth link 10, the fifth link 11, and the sixth link 12. The second X-type parasitic branch consists of the seventh link 13, the eighth link 14, the ninth link 15, the tenth link 16, the eleventh link 17, and the twelfth link 18. The first link 7 and the seventh link 13 are of equal length and parallel to each other; the second link 8 and the eighth link 14 are of equal length and parallel to each other; the third link 9 and the ninth link 15 are of equal length and parallel to each other; the fourth link 10 and the tenth link 16 are of equal length and parallel to each other; the fifth link 11 and the eleventh link 17 are of equal length and parallel to each other; and the sixth link 12 and the twelfth link 18 are of equal length and parallel to each other. The plane containing the first X-type parasitic branch is parallel to the plane containing the second X-type parasitic branch.

[0036] The first X-type parasitic branch has an electric drive module at its center, and the second X-type parasitic branch has a motor at its center. The motors of the electric drive module in the first X-type parasitic branch and the motor in the second X-type parasitic branch are not on the same straight line. The rotating shaft of the motor in the first X-type parasitic branch is fixedly connected to one end of the drive rod 20. The rotating shaft of the motor in the second X-type parasitic branch is also fixedly connected to one end of the drive rod 20. A hole is provided between the third link 9 and the fourth link 10, allowing the motor rotating shaft to pass through, thus enabling a movable connection between the motor rotating shaft and the third link 9 and the fourth link 10. Similarly, holes are provided between the ninth link 15 and the tenth link 16, allowing the motor rotating shaft to pass through, thus enabling a movable connection between the motor rotating shaft and the ninth link 15 and the tenth link 16.

[0037] like Figure 3 As shown, multiple connecting rods 19 are provided at the connection position between the two identical connecting rods of the first X-type parasitic branch and the second X-type parasitic branch. The connecting rods 19 are movably connected to the first X-type parasitic branch and the second X-type parasitic branch through cross roller bearings.

[0038] The electric drive module housing of the upper X-shaped parasitic branch of the hip folding mechanism is fixed to the torso. Both ends of the hip folding mechanism are connected to the upper part of the leg support plate via electric drive modules. The lower end of the leg support plate is connected to the center of the X-shaped parasitic branch inside the leg folding mechanism via an electric drive module. The lower end of the leg folding mechanism is connected to the foot. The lower part of the foot is connected to the sole via an electric drive module.

[0039] The electric drive module synchronizes the opening and closing of the X-shaped parasitic branches by driving the central node, thereby driving the connected components to complete the folding and unfolding actions. All links maintain a constant parallel relationship during movement, ensuring the stability and predictability of the trajectory during the folding and unfolding process. The electric drive module in the foot section can adjust its posture according to the terrain, improving the machine's adaptability to complex environments. All electric drive modules employ closed-loop control to guarantee motion accuracy and response speed.

[0040] The working principle of the double X-type parasitic branches is as follows: The first and second groups of parasitic branches each have two identical degrees of freedom. The double X-type unfolding mechanism connected in the above way also has only two degrees of freedom. When the mechanism becomes singular (multiple links collinear), the degrees of freedom of the mechanism will not suddenly increase or decrease, but will remain unchanged at two degrees of freedom, thereby ensuring that the robot can controllably pass through the singular position. In this way, the rotational range of the robot can be greatly increased to 360°.

[0041] The hip utilizes a rotational-extensional balancing parasitic mechanism, enabling the left and right legs to rotate around the hip, as well as to extend and retract around the hip in all directions. The hip can self-balance due to gravity in the horizontal direction, which significantly reduces the motor driving torque for the rotational and extensional movements of the hip.

[0042] The leg uses a rotary telescopic balance parasitic mechanism, which enables the leg to achieve gravity self-balancing in the vertical direction. That is, in the vertical direction, around the motor joint in the middle of the leg, the upper and lower gravity of the leg are balanced with each other, thereby greatly reducing the motor drive torque for the robot to lift its leg.

[0043] Thanks to the use of a balanced folding parasitic mechanism linkage, it has the ability to maintain structural parallelism between the output and input components (here referring to parallelism, which is not possible with serial mechanisms; serial mechanism robots require a motor at the ankle to control the foot angle, and the parallel relationship of the feet is achieved through motor algorithms, which places high demands on algorithms and real-time control). That is, the robot's hips and the feet of both legs are parallel, which means that on a level ground, as long as the feet are appropriately lengthened, the robot's total center of mass will not exceed the front and rear support range of the feet in the front and rear direction, thus structurally achieving the front and rear horizontal balance of the entire robot's torso.

[0044] Regarding left-right balance: the robot's hips and legs each have a 10-degree tilt angle, forming an inverted V-shape, such as... Figure 1 and Figure 3As shown. The significant advantage of this design is that, by tilting the legs at a 10-degree angle (but note that the feet remain horizontal), combined with the ability of the hips to extend and retract laterally, the landing support position of the feet can be easily controlled (without this tilt angle, the robot's feet would need to be very wide to ensure the robot's lateral balance). This position is precisely at the projection point of the robot's center of mass in the vertical direction of gravity, meaning the robot's center of mass falls within the support range of the feet, thus achieving the robot's lateral horizontal balance. Whether standing on two legs or supporting itself on one leg while walking, the two motors in the hips can easily and dynamically adjust the balance.

[0045] The robot possesses the ability to extend and retract its legs over a long distance using its hips. In addition to its basic walking and running abilities, it can further enhance its stride length by extending and retracting its legs over a longer distance. This extended hip extension and retraction can be up to three times the normal stride distance, thus allowing the robot to achieve a stride distance four times greater than a normal stride distance when running.

[0046] Note that when running, the feet do not necessarily need to be significantly longer. The foreleg acts as a fulcrum, and the body's center of gravity generates a clockwise torque on the foreleg fulcrum. At the same time, the robot's body center of gravity generates a horizontal forward inertial force due to the forward acceleration. This inertial force generates a counterclockwise torque on the foreleg fulcrum. The two torques can partially or completely cancel each other out, which allows the dynamic balance of running to be achieved without even needing to lengthen the feet.

[0047] A shoulder section is located between the head and torso. The head is connected to the rotating shaft of an electric drive module, which is fixed below the shoulder section, and the shoulder is fixedly connected to the torso. Both ends of the shoulder section are connected to the arm section, specifically as follows: both ends of the shoulder section are fixedly connected to the rotating shaft of the electric drive module, and the square frame of the electric drive module is connected to one end of a short rod; the other end of the short rod is connected to the rotating shaft of another electric drive module, the outer shell of which is fixedly connected to the arm section. By placing electric drive modules between the shoulder and the short rod, and simultaneously placing electric drive modules between the short rod and the arm section, the arm section's movement becomes more flexible.

Claims

1. A humanoid robot structure with a balancing folding parasitic mechanism, comprising a head, arms, torso, hips, legs, and feet, wherein the head is connected to the upper part of the torso, the upper part of the torso has shoulders connected to the arms, the lower part of the torso is connected to the hips, the sides of the hips are connected to the legs, and the lower parts of the legs are connected to the feet; characterized in that, The hips and legs are equipped with a folding mechanism; The folding mechanism employs a double-X parasitic branch combination. The specific positions and connections of the double-X parasitic branches are as follows: The first X parasitic branch consists of the first, second, third, fourth, fifth, and sixth connecting rods; the second X parasitic branch consists of the seventh, eighth, ninth, tenth, eleventh, and twelfth connecting rods; the first and second X parasitic branches have identical external dimensions, and the planes on which the first and second X parasitic branches are located are parallel to each other; electric drive modules are respectively installed at the center of the first and second X parasitic branches, and the axes of these two electric drive modules are not on the same straight line; The electric drive module housing of the upper X-shaped parasitic branch of the hip folding mechanism is fixed to the torso. The two ends of the hip folding mechanism are connected to the upper part of the leg support plate through the electric drive module. The lower end of the leg support plate is connected to the center of the X-shaped parasitic branch inside the leg folding mechanism through the electric drive module. The lower end of the leg folding mechanism is connected to the foot.

2. The humanoid robot structure with a balanced folding parasitic mechanism according to claim 1, characterized in that, The electric drive module is externally a square frame with fixing holes on four sides and a shaft hole at the center of each side. An electric motor is fixed inside the square frame, and the motor's rotating shaft passes through the shaft hole and extends out of the square frame.

3. The humanoid robot structure with a balanced folding parasitic mechanism according to claim 1, characterized in that, The legs are not perpendicular to the horizontal plane; the upper part of the legs leans outward, and the lower part leans inward.

4. The humanoid robot structure with a balanced folding parasitic mechanism according to claim 1, characterized in that, The lower part of the foot is connected to the ball of the foot via an electric drive module.

5. The humanoid robot structure with a balanced folding parasitic mechanism according to claim 1, characterized in that, The shoulder and head are connected by an electric drive module. The housing of the electric drive module is fixed below the shoulder, and the rotating shaft of the electric drive module is fixedly connected to the head.

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