Rope-driven humanoid five-finger manipulator with self-adaptive adsorption in palm center

Abstract

The utility model discloses a rope-driven humanoid five-finger manipulator with a self-adaptive adsorption function at the palm center, which comprises a hand mechanism comprising a manipulator palm and fingers, a plurality of fingers are assembled with the manipulator palm, and each finger also comprises a plurality of knuckles which are mutually hinged; the grasping mechanism comprises a pull rope penetrating through the palm and the knuckles of the manipulator; according to the unfolding mechanism, torsional springs are arranged at the hinged positions of the adjacent knuckles, and the torsional springs enable the two adjacent knuckles to have elastic potential energy for enlarging the included angle; the artificial muscle material is used for sensing the deformation of the knuckles and transmitting electric signals; wherein the distance from the pull rope to the inner front side of the finger is larger than that from the pull rope to the back side of the finger, and the artificial muscle material is located on the back side of the finger. The grabbing and loosening unfolding mechanism is simple and reliable in principle and low in cost. And due to the characteristics of the artificial muscle material, the knuckle deformation amplitude can be monitored in real time, and mechanical finger deformation caused by overlarge load when a special target object is grabbed is avoided.

Description

Technical Field

[0001] The utility model relates to the field of manipulators, in particular to a rope-driven humanoid five-fingered manipulator with adaptive adsorption on the palm. Background Art

[0002] Currently, most manipulators are rigid, typically designed with rigid joints and linkages that allow the end effector to achieve the target position and motion within the workspace. Power is transmitted at the joints of the manipulator using transmission components such as motors and gear reducers. However, this integrated drive unit and manipulator structure is not compact. Furthermore, the motor, acting as the joint drive unit, is installed at the joint, increasing the manipulator's weight. This results in low transmission efficiency, large moment of inertia, and difficulty in achieving precise position control. Furthermore, the limited number of degrees of freedom and poor flexibility make it difficult to meet the manipulator's operational requirements in complex spatial conditions.

[0003] In the related art, the manipulator of a humanoid robot includes five fingers, each of which includes multiple rotational joints, so that the manipulator has excellent dynamic response capability and adaptive grasping capability.

[0004] Many humanoid manipulators in the existing technology are unable to achieve unpowered adaptive resetting of fingers. In particular, relatively low-cost humanoid manipulators also lack the adsorption force to assist in grasping target objects and are unable to monitor finger deformation. Utility Model Content

[0005] The problem addressed by this utility model is to provide a five-fingered, rope-driven, humanoid manipulator with adaptive palm gripping. The grasping and releasing mechanism is simple, reliable, and cost-effective. The properties of the artificial muscle material also allow for real-time monitoring of knuckle deformation, preventing deformation of the manipulator's fingers due to excessive load when grasping specific objects.

[0006] To solve the above problems, the present invention provides a five-fingered, rope-driven, humanoid manipulator with adaptive adsorption on the palm. To achieve the above objectives, the present invention adopts the following technical solutions to solve the technical problems:

[0007] A rope-driven anthropomorphic five-fingered manipulator with adaptive adsorption on the palm comprises: a hand mechanism, including a manipulator palm and fingers, with several fingers assembled with the manipulator palm, and each finger also comprising several mutually hinged knuckles; a grasping mechanism, including a pull rope passing through the manipulator palm and knuckles; an unfolding mechanism, wherein the hinges of adjacent knuckles are provided with torsion springs, which impart elastic potential energy to two adjacent knuckles by increasing the angle between them; and artificial muscle material, which senses deformation of the knuckles and transmits electrical signals; wherein the distance from the pull rope to the inner front side of the finger is greater than the distance to the back side of the finger, and the artificial muscle material is located on the back side of the finger.

[0008] As a further improvement of the present invention, the back of the knuckle is provided with an assembly groove for accommodating the artificial muscle material, and the inner surface of the artificial muscle material is glued and fixed to the bottom surface of the assembly groove.

[0009] As a further improvement of the present invention, the outer surface of the artificial muscle material is covered with a layer of epoxy resin, and the outer surface of the epoxy resin is flush with the opening of the assembly groove.

[0010] As a further improvement of the present invention, the artificial muscle materials of different finger joints are connected by wires, and the wires are located on one side of the finger.

[0011] As a further improvement of the present invention, the hand mechanism includes a manipulator palm and five fingers, the five fingers including a thumb, index finger, middle finger, ring finger, and little finger; the thumb includes three knuckles hinged to each other, and the index finger, middle finger, ring finger, and little finger each include four knuckles hinged to each other; the knuckles of the index finger, middle finger, ring finger, and little finger connected to the manipulator palm are fixed as a whole with the manipulator palm, and the knuckles of the thumb connected to the manipulator palm are hinged to the manipulator palm.

[0012] As a further improvement of the present invention, a pull rope passes through the palm and fingers of the manipulator, one end of the pull rope is connected to a motor, the other end of the pull rope is fixed to the knuckle at the end of the finger, and a rope hole is provided inside the finger for the pull rope to pass through.

[0013] As a further improvement of the present invention, the surface of the palm of the manipulator is provided with a suction cup.

[0014] As a further improvement of the present invention, the surface of the palm of the manipulator has a concave inner surface, and a plurality of suction cups are located on the concave inner surface.

[0015] As a further improvement of the present invention, the interior of the palm of the manipulator is provided with a cavity, the cavity is connected to a negative pressure generator, and the interior of the suction cup is provided with a vent hole, which is connected to the cavity.

[0016] As a further improvement of the present invention, a spherical cavity with two through ends is provided between the surface of the palm of the robot arm and the cavity, the suction cup is connected to a spherical pair, the spherical pair is assembled with the spherical cavity and the spherical pair has the freedom of rotation in the spherical cavity, and the vent runs through the suction cup and the spherical pair.

[0017] The beneficial effects of adopting the solution of the present application are: the humanoid manipulator has a simple structure, compact structure and low cost. First, the fingers are operated by a pull rope to enable grasping. Secondly, the fingers are spread out by a torsion spring to achieve unpowered adaptive reset and flexible operation. Whether it is a pull rope or a torsion spring, both have short transmission chains, low energy consumption and low cost. Then, due to the drive of the pull rope, the manipulator can grasp objects like a human hand, especially for grasping objects with complex shapes. Finally, artificial muscle materials are attached to the fingers, and the characteristics of artificial muscle materials can be used to monitor the deformation amplitude of the knuckles in real time to avoid deformation of the manipulator fingers due to excessive load when grasping special target objects. The manipulator has a feedback function, which improves the intelligence of the manipulator. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] 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 these drawings without paying any creative work.

[0019] Figure 1 It is a perspective view of an embodiment of the present utility model;

[0020] Figure 2 This is an assembly diagram of the fourth finger joint and the third finger joint of one embodiment of the utility model;

[0021] Figure 3 It is a three-dimensional diagram of the first knuckle of the thumb according to one embodiment of the present invention;

[0022] Figure 4 It is a three-dimensional diagram of the second knuckle of the thumb according to one embodiment of the present invention;

[0023] Figure 5 This is a three-dimensional diagram of the third knuckle of the thumb according to one embodiment of the present invention;

[0024] Figure 6 This is a three-dimensional diagram of the palm of a manipulator according to one embodiment of the present invention;

[0025] Figure 7 This is an assembly diagram of a suction cup and a spherical pair according to one embodiment of the present invention;

[0026] Figure 8 This is a schematic diagram of the application of a drawstring according to one embodiment of the present invention;

[0027] Figure 9 This is a cross-sectional view of a manipulator palm according to one embodiment of the present invention;

[0028] Figure 10 This is a schematic diagram of the assembly of the first artificial muscle, the second artificial muscle, and the third artificial muscle in one embodiment of the present utility model;

[0029] Figure 11 It is a three-dimensional diagram of an assembly groove in one embodiment of the present utility model.

[0030] 1-first knuckle; 2-second knuckle; 3-third knuckle; 4-fourth knuckle; 5-first torsion spring; 6-second torsion spring; 7-third torsion spring; 8-hinge axis; 9-manipulator palm; 10-suction cup; 11-spherical pair; 12-pull rope; 13-cavity; 14-side wire hole of first knuckle; 15-side wire hole of second knuckle; 16-side wire hole of third knuckle; 17-first artificial muscle; 18-second artificial muscle; 19-third artificial muscle; 20-ventilation hole; 21-inner concave surface; 22-spherical cavity; 23-rope hole; 24-oblique end surface; 25-wire; 26-assembly slot; 27-thumb root joint. DETAILED DESCRIPTION

[0031] The following is a further detailed description of the present invention in conjunction with specific embodiments:

[0032] The five-fingered, rope-driven, humanoid manipulator with adaptive adsorption in the palm is similar to a human, and includes five fingers and a manipulator palm 9. The five fingers are mounted on the manipulator palm 9 in the same manner as a human hand. Each of the four fingers, except the thumb, includes a first knuckle 1, a second knuckle 2, a third knuckle 3, a fourth knuckle 4, and an inner rope. The thumb includes a first knuckle 1, a second knuckle 2, a third knuckle 3, a first type of inner rope, and a second type of inner rope. The base of the first knuckle 1 of each finger, except the thumb, is integrally connected to the manipulator palm 9. The first knuckle 1 of the thumb is hinged to the manipulator palm 9. The first knuckle 1 of the thumb is hinged to the manipulator palm 9. The first knuckle 1, second knuckle 2, third knuckle 3, and fourth knuckle 4 are hinged in sequence. The first knuckle 1, second knuckle 2, and third knuckle 3 of the thumb are hinged in sequence. The inner rope is set on the inner rope of the finger. The end of the first type of inner rope is connected to the fourth knuckle (fingers except thumb) or the third knuckle (thumb), and the second type of inner rope is connected to the first knuckle of the thumb. Figure 3 As shown, the first joint 1 of the thumb is also called the thumb root joint 27.

[0033] A first torsion spring 5 is provided on the hinge shaft 8 of the first joint 1 and the second joint 2 of the four fingers except the thumb, and the two ends of the first torsion spring 5 are respectively in contact with the ends of the first joint 1 and the second joint 2. A second torsion spring 6 is provided on the hinge shaft 8 of the second joint 2 and the third joint 3, and the two ends of the second torsion spring 6 are respectively in contact with the ends of the second joint 2 and the third joint 3. A third torsion spring 7 is provided on the hinge shaft 8 of the third joint 3 and the fourth joint 4, and the two ends of the third torsion spring 7 are respectively in contact with the ends of the third joint 3 and the fourth joint 4. A first torsion spring 5 is provided on the hinge shaft 8 of the first joint 1 of the thumb and the palm 9 of the manipulator, and the two ends of the first torsion spring 5 are respectively in contact with the palm 9 of the manipulator and the end of the first joint 1. A second torsion spring 6 is provided on the hinge shaft 8 of the first joint 1 and the second joint 2 of the thumb, and the two ends of the second torsion spring 6 are respectively in contact with the ends of the first joint 1 and the second joint 2. A third torsion spring 7 is provided on the hinge shaft 8 of the second joint 2 and the third joint 3 of the thumb, and the two ends of the third torsion spring 7 are respectively in contact with the ends of the second joint 2 and the third joint 3.

[0034] like Figure 2 、 Figure 4 、 Figure 5 As shown, in order to ensure the rotational freedom of adjacent finger joints, the end of the joint has an oblique end surface 24, and the oblique end surface 24 forms a non-right angle with the length direction of the finger joint itself.

[0035] In this five-fingered, rope-driven, humanoid manipulator with adaptive palm suction, each of the four fingers, excluding the thumb, has rope holes 23 on the inner sides of their knuckles. The rope hole 23 from the fourth knuckle 4 to the first knuckle 1 is sequentially followed by the first, second, third, and fourth rope holes. The fourth rope hole pierces both the first knuckle 1 and the manipulator palm 9. The thumb also has rope holes on its inner sides. From the distal knuckle, the rope holes 23 are sequentially followed by the first, second, third, and fourth rope holes. Finally, there is the fourth rope hole on the manipulator palm 9, located below the third rope hole. Furthermore, there is a sixth rope hole on the first knuckle and a seventh rope hole below it on the manipulator palm 9. The first type of inner rope passes through the first, second, third, and fourth rope holes in sequence; the second type of inner rope passes through the sixth and seventh rope holes in sequence.

[0036] There is a smooth concave surface 21 on the palm of the manipulator 9, and a cavity 13 is provided inside the lower part of the concave surface 21 (i.e., the palm of the manipulator 9). Suction cups 10 are evenly distributed on the concave surface 21, and the size of the suction cups 10 is a miniature suction cup. The connection between the suction cups 10 and the concave surface 21 is a ball-pair connection, that is, one end of each suction cup 10 is connected to a spherical pair 11. A vent 20 is provided in the spherical pair 11 to allow external air to pass through the suction cup 10. The part between the concave surface 21 and the cavity 13 has a spherical cavity 22 that is movably assembled with the spherical pair 11, so that the suction cup 10 has the freedom to swing around the spherical pair 11. The spherical pair 11 is in communication with the cavity 13. An M8 threaded hole is also provided below the palm of the manipulator 9 to communicate with the cavity 13, and forms a negative pressure system with the negative pressure generator as a whole.

[0037] The thumb has three degrees of freedom. The initial posture of the finger is when the four knuckles of each finger, excluding the thumb, are swung in the same direction in a straight line. The angle between the connected knuckles in the initial posture is 180°, and the angle between the adjacent knuckles in the active state ranges from 90° to 180°. In the initial posture, the second knuckle 2 and the third knuckle 3 of the thumb are in the same direction, and the direction is perpendicular to the plane of the manipulator palm 9. The connection relationship between the first knuckle 1 and the second knuckle 2 of the thumb is an angle of 120° in the initial posture. The swing angle range of the first knuckle 1 of the thumb is 47° to 117°. The angle between the second knuckle 2 of the thumb relative to the spatial plane where the swing direction of the first knuckle 1 is located, the angle between the third knuckle 3 of the thumb relative to the spatial plane where the swing direction of the second knuckle 2 is located, and the angle between the first knuckle 1 and the spatial plane where the swing direction of the manipulator palm 9 is located is 60°.

[0038] In other embodiments of the present invention, the first knuckle 1, the second knuckle 2, and the third knuckle 3 on the four fingers excluding the thumb are all mounted with IPMC material. IPMC, the full name in English, is Ionic Polymer Metal Composites. It is an ion exchange polymer metal material, that is, an artificial muscle material that can produce a large displacement deformation using a relatively low driving voltage. From the first knuckle 1 to the third finger 3, there are the first artificial muscle 17, the second artificial muscle 18, and the third artificial muscle 19 respectively. A shallow assembly groove 26 is provided on the back of the knuckle, and a wire hole is provided on one side of the assembly groove 26. As shown in the figure, the wire hole contains a wire 25 electrically connected to the artificial muscle. The wire 25 is used to transmit the electrical signal transmitted back by the artificial muscle material. The artificial muscle material is located in the assembly groove 26. The artificial muscle material is attached to the assembly groove 26 by a thin layer of glue. A layer of epoxy resin is then encapsulated on the artificial muscle material, and the surface of the epoxy resin is flush with the surface of the knuckle. There are knuckle side line holes on the side of the finger joints, from the first knuckle 1 to the third knuckle 3, which are the first knuckle side line hole 14, the second knuckle side line hole 15, and the third knuckle side line hole 16 in sequence.

[0039] In other embodiments of the present invention, in order to ensure that the first artificial muscle 17, the second artificial muscle 18, and the third artificial muscle 19 can be adjacent to each other, the assembly groove 26 has, in addition to the main opening located on the back of the finger, a secondary opening located at the end of the knuckle of the finger, and the artificial muscle material exposed at the secondary opening can contact the end of the knuckle of the adjacent finger.

[0040] The present application is driven by a pull rope 12, which has a simple structure, low energy consumption, and is more flexible overall. The bending of the fingers is controlled by the inner pull rope 23 to provide a gripping advantage, and the fingers are reset by the torsion spring to open the fingers, thereby achieving non-powered adaptive reset. The concave structure of the concave surface 21 of the manipulator palm 9 and the micro suction cups 10 arrayed on the concave surface 21 are used to perform adaptive auxiliary adsorption and grasping of the target object, providing additional adsorption force and improving grasping stability. Finally, by attaching artificial muscle materials and utilizing the characteristics of artificial muscle materials, the deformation amplitude of the knuckles can be monitored in real time to avoid deformation of the manipulator fingers due to excessive load when grasping special target objects.

[0041] In other embodiments of the present invention, Figure 3 As shown, the hinge axes at both ends of the first phalanx 1 of the thumb form an angle with each other.

[0042] In other embodiments of the present invention, the pull ropes 12 of the five fingers are connected to a motor, and the motor pulls each pull rope 12 independently.

[0043] In other embodiments of the present invention, a plurality of miniature suction cups 10 are evenly distributed on the manipulator palm 9. The suction cups 10 can be arranged in a circular or rectangular array. The inner concave surface 21 is a concave curved surface. The suction cups 10 are connected to the inner concave surface 21 by a spherical joint. The spherical joint 11 is provided with a vent 20, allowing external air to pass through the suction cups 10 and then through an external negative pressure generator connected to the bottom of the manipulator, thereby forming a negative pressure system.

[0044] During operation, when the manipulator approaches a target object, the motor rotates forward, tightening the pull cord 12 and causing the five fingers to bend in a certain order. At this point, the negative pressure system activates, and the suction cup 10 absorbs the target object. The fingers then clench, grasping the target object. The manipulator can quickly reset itself with the help of the first torsion spring 5, the second torsion spring 6, and the third torsion spring 7. When the motor rotates in reverse, the pull cord 12 is released, and the torsion springs reset the adjacent knuckles to a 180° angle.

[0045] In other embodiments of the present invention, during the process from the robot arm contacting the target object to grasping the target object, the artificial muscle material attached to the first joint 1, second joint 2, and third joint 3 of the four fingers (excluding the thumb) can sense the deformation of the corresponding joints and transmit electrical signals. When the mass of the target object is too large, when the electrical signal (voltage difference) transmitted back by the artificial muscle material exceeds the corresponding voltage difference of the joint safety deformation threshold, the fingers extend, and the negative pressure module stops working, giving up grasping the target object. This design enables the robot arm to have a certain degree of self-adjustment feedback capability.

[0046] The present application discloses a five-finger manipulator imitating a human hand, comprising a palm, five fingers, and a rope drive mechanism. Each finger has multiple knuckles, and each finger except the thumb is extended and flexed by a rope drive mechanism and a torsion spring at the connection between the knuckles.

[0047] The thumb is extended and flexed by a set of rope drive mechanisms and torsion springs at the joints of the knuckles, while another set of rope drive mechanisms and torsion springs at the joints of the knuckles enable the thumb to swing. Any two adjacent knuckles of each finger are connected by a hinge shaft 8. The knuckles closest to the palm of each finger, excluding the thumb, are integrated with the palm, while the knuckles of the thumb closest to the palm are connected to the palm via a shaft. The end of the pull rope 12 is located at the terminal knuckle of each finger. The pull rope 12 passes through each knuckle of the corresponding finger in sequence, and then passes through the palm, and then reaches the rope traction mechanism on the back of the palm. A torsion spring is installed at the connection between each adjacent knuckle to reset the finger.

[0048] The palm of the robot hand features a smooth groove (i.e., concave surface 21), which is fitted with a micro-negative pressure suction cup 10 for suctioning and securing objects. Artificial muscle material is attached to the backs of the first, second, and third knuckles of each of the four fingers (excluding the thumb) to monitor their deformation in real time. The artificial muscle material can be an ion-exchange polymer metal.

[0049] The manipulator of the present application has a simple, compact structure and low cost. The fingers are operated directly through the tough pull rope 12 and the torsion spring, which is flexible to operate, and has a short transmission chain and low energy consumption. Due to the drive of the pull rope 12, the manipulator of the present application can grasp objects like a human hand, especially for grasping objects with complex shapes. The manipulator of the present application has a miniature suction cup 10 on the palm, which can adaptively adsorb the target object, which is conducive to grasping the target object. The manipulator of the present application has artificial muscle material attached to the back of the knuckles to monitor the deformation of the knuckles in real time to ensure the structural safety of the manipulator.

[0050] The above embodiments are only for illustrating the technical concept and features of the present invention. Their purpose is to enable people familiar with this technology to understand the content of the present invention and implement it. They are not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the scope of protection of the present invention.

Claims

1. A five-fingered, rope-driven, humanoid manipulator with adaptive adsorption on the palm, characterized in that: include: The hand mechanism includes a manipulator palm and fingers. Several fingers are assembled with the manipulator palm, and each finger also includes several knuckles that are hinged to each other. a grasping mechanism, including a drawstring passing through the palm and knuckles of the manipulator; The expansion mechanism is provided with a torsion spring at the hinge of adjacent knuckles, which provides elastic potential energy for the two adjacent knuckles to expand the angle between them; Artificial muscle materials that sense knuckle deformation and transmit electrical signals; The distance from the pull rope to the inner front side of the finger is greater than the distance to the back side of the finger, and the artificial muscle material is located on the back side of the finger.

2. The five-fingered, rope-driven, humanoid manipulator with adaptive palm adsorption according to claim 1, characterized in that: The back of the finger joint is provided with an assembly groove for accommodating the artificial muscle material, and the inner surface of the artificial muscle material is glued and fixed to the bottom surface of the assembly groove.

3. The rope-driven humanoid five-fingered manipulator with adaptive palm adsorption according to claim 2, characterized in that: The outer surface of the artificial muscle material is covered with a layer of epoxy resin, and the outer surface of the epoxy resin is flush with the opening of the assembly groove.

4. The five-fingered, rope-driven, humanoid manipulator with adaptive palm adsorption according to claim 1, characterized in that: The artificial muscle materials of different finger joints are connected by wires, and the wires are located on one side of the finger.

5. The rope-driven humanoid five-fingered manipulator with adaptive palm adsorption according to claim 1, characterized in that: The hand mechanism includes a manipulator palm and five fingers, the five fingers including a thumb, an index finger, a middle finger, a ring finger, and a little finger; the thumb includes three mutually hinged knuckles, and the index finger, middle finger, ring finger, and little finger each include four mutually hinged knuckles; The knuckles of the index finger, middle finger, ring finger and little finger connected to the palm of the manipulator are fixed integrally with the palm of the manipulator, and the knuckles of the thumb connected to the palm of the manipulator are hinged with the palm of the manipulator.

6. The five-fingered, rope-driven, humanoid manipulator with adaptive palm adsorption according to claim 1, characterized in that: The pull rope passes through the palm and fingers of the manipulator, one end of the pull rope is connected to a motor, the other end of the pull rope is fixed to the knuckle at the end of the finger, and a rope hole is provided inside the finger for the pull rope to pass through.

7. The five-fingered, rope-driven humanoid manipulator with adaptive palm adsorption according to claim 1, characterized in that: The surface of the palm of the robot arm is provided with a suction cup.

8. The five-fingered, rope-driven, humanoid manipulator with adaptive palm adsorption according to claim 7, characterized in that: The surface of the palm of the manipulator is provided with a concave inner surface, and a plurality of suction cups are located on the concave inner surface.

9. The five-fingered, rope-driven, humanoid manipulator with adaptive palm adsorption according to claim 7, characterized in that: The palm of the manipulator has a cavity inside, the cavity is connected to a negative pressure generator, and the suction cup has an air vent inside, the air vent is connected to the cavity.

10. The five-fingered, rope-driven humanoid manipulator with adaptive palm adsorption according to claim 9, characterized in that: A spherical cavity with two through ends is provided between the surface of the manipulator palm and the cavity. The suction cup is connected to a spherical pair. The spherical pair is assembled with the spherical cavity and has the freedom of rotation in the spherical cavity. The vent runs through the suction cup and the spherical pair.

Images