Dual-drive multi-joint bionic gripper

Abstract

The present invention relates to the field of robots. The purpose is to provide a dual-drive multi-fingered bionic gripper, which should be able to combine the advantages of a rigid link mechanism and a flexible bionic mechanism, and has the characteristics of simple structure and high reliability. The technical solution is: a dual-drive multi-fingered bionic gripper, characterized in that: the gripper includes a frame, a first motor for driving the frame to rotate around an axis, a second motor arranged in the frame, a support platform telescopically positioned at the front end of the frame, a plurality of gripper branches arranged around the support platform, and a transmission mechanism for transmitting the power of the second motor to drive the support platform and the gripper branches to move; the transmission mechanism includes a guide rail arranged in the frame and parallel to the length direction of the frame, a push plate that can slide along the guide rail, a screw driven by the second motor, and a nut that meshes with the screw rod and is fixed on the push plate; the support platform can be slidably positioned on the guide rail, and a plurality of connecting blocks are arranged on the support platform, and the connecting blocks and the push plate are connected by an elastic body.

Description

Technical Field

[0001] The invention relates to the field of robots, in particular to a double-drive multi-fingered bionic gripper used for a robot end execution part. Background Art

[0002] Existing grippers are mainly divided into rigid linkage mechanisms and flexible bionic mechanisms, among which: the ends of rigid linkage mechanisms are mostly metal fixtures, which cannot meet the needs of grasping fragile objects or objects that require special surface protection; the flexible bionic mechanism is simpler in structure than the rigid linkage mechanism and causes less damage to the surface of the target object. However, the flexible bionic mechanism requires specially made corresponding clamps for the task of grasping new parts. Some grippers made of special materials are relatively expensive, which increases time and production costs; at the same time, the mechanical structure of existing grippers has too many drives and is not reliable. Summary of the invention

[0003] The purpose of the present invention is to overcome the deficiencies in the above-mentioned background technology and to provide a dual-drive multi-fingered bionic gripper, which should be able to combine the advantages of a rigid linkage mechanism and a flexible bionic mechanism and have the characteristics of simple structure and high reliability.

[0004] The technical solution of the present invention is:

[0005] A dual-drive multi-fingered bionic gripper, characterized in that: the gripper comprises a frame, a first motor for driving the frame to rotate around an axis, a second motor arranged in the frame, a support platform telescopically positioned at the front end of the frame, a plurality of gripper branches arranged around the support platform, and a transmission mechanism for transmitting power from the second motor to drive the support platform and the gripper branches to move;

[0006] The transmission mechanism includes a guide rail arranged in the frame and parallel to the length direction of the frame, a push plate that can slide along the guide rail, a screw driven by a second motor, and a nut engaged with the screw and fixed on the push plate; the support platform can be slidably positioned on the guide rail, and a plurality of connecting blocks are arranged on the support platform, and the connecting blocks are connected to the push plate through an elastic body;

[0007] The gripper branch is a quadrilateral mechanism formed by hingedly connecting the first connecting rod, the second connecting rod, the third connecting rod and the fourth connecting rod in sequence. The first connecting rod is hingedly connected to the connecting block rotatably, the third connecting rod is hingedly connected to the frame rotatably, and the fourth connecting rod is provided with a fifth connecting rod.

[0008] The first motor is arranged at the rear end of the frame, and the rotating shaft of the first motor is fixed to the frame through a coupling.

[0009] In the grab branch, one end of the first connecting rod is rotatably hinged on the connecting block, the two ends of the third connecting rod are respectively rotatably hinged on the middle part of the first connecting rod and one end of the fourth connecting rod, the middle part of the third connecting rod is rotatably hinged on the frame, and the two ends of the second connecting rod are respectively rotatably hinged on the other end of the first connecting rod and the other end of the fourth connecting rod.

[0010] The fifth connecting rod is fixed to one end of the fourth connecting rod close to the third connecting rod. The fifth connecting rod is curved in an arc shape, and the portion of the third connecting rod between the frame and the fourth connecting rod is also curved in an arc shape.

[0011] The rack comprises a first rack plate, a rack platform, a second rack plate, a plurality of first rack rods fixed between the first rack plate and the rack platform, and a plurality of second rack rods fixed between the rack platform and the second rack plate.

[0012] The second motor is fixed in the frame platform; the guide rail is arranged between the frame platform and the second frame plate and is fixed to the frame platform; the guide rail is a hollow cylinder, and a plurality of slide grooves arranged along the busbar direction are provided on the guide rail.

[0013] The push plate includes a first plate body and second plate bodies radially arranged around the first plate body, the first plate body is located in the inner cavity of the guide rail, the second plate body is slidably matched with the slide groove and the second plate body passes through the slide groove and extends out of the guide rail.

[0014] The support platform is a hollow cylinder which is slidably mounted on the guide rail, and a through hole for the movement of the support platform is arranged at the center of the second frame plate.

[0015] The beneficial effects of the present invention are:

[0016] The present invention proposes a dual-drive multi-joint bionic gripper that combines a rigid connecting rod mechanism with a flexible bionic mechanism, wherein the gripper branches adopt a bionic structure and are made of a composite material or a metal material, and a spherical outline is generated during the grasping operation, thereby increasing the friction and contact area with the object, which can not only ensure the clamping effect, but also ensure good compliance with irregular objects; the present invention realizes the adjustment of the clamping position and the clamping force through motor drive, and during the grasping process, one motor actively adjusts the clamping force of the gripper and the size of the spherical volume enclosed by the gripper, and the other motor drives the entire device to rotate, thereby providing a torque to the gripper, which not only simplifies the structure, but also improves the reliability of the system; the present invention is installed at the end of the robot, which improves the success rate of grasping objects and the safety of the working space, is conducive to human-machine collaboration, and has the characteristics of streamlined structure, smooth process, low production cost, and high work efficiency, and can be widely used in industrial production, agricultural fruit and vegetable picking robots and other fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a three-dimensional structural schematic diagram of the present invention.

[0018] Figure 2 It is a main structural schematic diagram of the present invention.

[0019] Figure 3 It is one of the schematic diagrams of the grab branch in the present invention (open state).

[0020] Figure 4 This is the second schematic diagram of the grab handle branch in the present invention (folded state).

[0021] Figure 5 It is a schematic diagram of the rack in the present invention.

[0022] Figure 6 It is a schematic diagram of the frame platform, guide rails and push plate in the present invention.

[0023] Figure 7 yes Figure 6 Schematic diagram of the cross-sectional structure.

[0024] Figure 8 It is a schematic diagram of the second motor, the lead screw and the push plate in the present invention.

[0025] Fig. 9 It is a schematic diagram of the support platform in the present invention. DETAILED DESCRIPTION

[0026] The present invention will be further described below in conjunction with the accompanying drawings, but the present invention is not limited to the following embodiments.

[0027] like Figure 1 As shown, the dual-drive multi-joint bionic gripper includes a frame, a first motor 1, a second motor 11, a support platform 8, a gripper branch and a transmission mechanism. The first motor is arranged at the rear end of the frame ( Figure 2 The first motor is used to drive the frame to rotate around the axis, the second motor is arranged in the frame, and the support platform can be telescopically positioned at the front end of the frame ( Figure 2 A plurality of gripper branches are also arranged at the front end of the frame and are evenly arranged around the support platform, and a transmission mechanism is used to transmit the power of the second motor to drive the support platform and the gripper branches to move. Three gripper branches are evenly arranged around the support platform.

[0028] In the rack, the first rack plate 6, the rack platform 4 and the second rack plate 7 are arranged along the length direction of the rack ( Figure 2The first frame rods 3 are vertically fixed between the first frame plate and the frame platform, and the second frame rods 10 are vertically fixed between the frame platform and the second frame plate. The first motor shaft is fixed to the first frame plate through a coupling 2. The rotation of the first motor drives the entire frame to rotate. A cavity is provided inside the frame platform, and the second motor is fixed in the cavity (the tail end of the second motor is fixed to the end face of the frame platform); a through hole 7.1 is provided in the center of the second frame plate. The first frame rods of different lengths can be replaced to change the size of the entire frame and adjust the working space of the multi-fingered bionic gripper. The first frame rods of different lengths can be replaced to change the sliding stroke of the push plate 13 and the limit range of the envelope 5, and adjust the grasping range of the multi-fingered bionic gripper.

[0029] In the transmission mechanism; the guide rail is a hollow cylinder parallel to the length direction of the frame, and a plurality of slide grooves 9.1 parallel to the length direction of the frame are provided in the generatrix direction of the guide rail (a total of three slide grooves are shown in the figure), the guide rail is fixed to the bottom surface of the frame platform (the side facing the second frame plate) and is arranged between the frame platform and the second frame plate; the screw rod 12 is driven by the second motor, the screw rod is parallel to the length direction of the frame and is arranged in the inner cavity of the guide rail; the push plate 13 can slide along the guide rail, the push plate includes a first plate body 13.1 and a plurality of second plate bodies 13.2 radially arranged around the first plate body (a total of three second plate bodies are shown in the figure), the first plate body is located in the inner cavity of the guide rail, the second plate body is slidably matched with the slide groove, and the second plate body passes through the slide groove and extends out of the guide rail; the nut (omitted in the figure) is engaged with the screw rod and is fixed to the first plate body of the push plate.

[0030] The support is a hollow cylinder parallel to the length direction of the frame. The inner diameter of the support is consistent with the outer diameter of the guide rail. The support passes through the through hole in the center of the second frame plate and can be slidably mounted on the guide rail. A number of connecting blocks 14 are evenly arranged around the support (three connecting blocks are shown in the figure), and the connecting blocks are connected to the push plate by an elastic body 20; the elastic body can be an elastic rope.

[0031] The gripper branch is a quadrilateral mechanism, including a first link 15, a second link 16, a third link 17 and a fourth link 18 which are hinged in sequence, and a fifth link 19 is fixed to the fourth link. Among them, one end of the first link is rotatably hinged on the connecting block, the middle part of the third link is rotatably hinged on the second frame plate, one end of the third link is rotatably hinged on the middle part of the first link, the other end of the third link is rotatably hinged on one end of the fourth link, the two ends of the second link are rotatably hinged on the other end of the first link and the other end of the fourth link, the fifth link is fixed on one end of the fourth link (close to the end of the third link), the fifth link is curved, and the third link (located between the second frame plate and the fourth link) is curved.

[0032] When the second motor drives the push plate to move toward the second frame plate, the push plate pushes the support platform to extend outward, and at the same time, the support platform drives the three gripper branches to open through the connecting block. When the second motor drives the push plate to move in the opposite direction, the push plate pulls the support platform inward through the elastic body, and at the same time, the three gripper branches are closed, and the elastic body plays a buffering role.

[0033] The multi-jointed bionic gripper can adaptively contact objects and maintain a certain friction force, which can well guarantee the gripping efficiency of objects with special shapes. It is especially suitable for grasping fragile and soft objects such as eggs or tomatoes that are easily damaged. Compared with existing rigid grippers, the multi-jointed bionic gripper has superior flexibility, safety and reliability.

[0034] The key to this multi-joint bionic gripper is that the three gripper branches can realize the two actions of clasping and pulling. When grasping an object, the gripper branches first close inward to hold the object and press the object on the support platform, and then the gripper branches continue to close while the support platform retreats, so that the gripper branches can wrap the object more effectively. The elastic body can play a buffering role when the gripper branches cannot continue to close, avoiding damage to the object. At the same time, the first motor can drive the entire gripper to rotate and generate additional torque.

[0035] The above-mentioned specific implementation can be partially adjusted in different ways by those skilled in the art without departing from the principle and purpose of the present invention. The protection scope of the present invention shall be based on the claims and shall not be limited by the above-mentioned specific implementation. Each implementation scheme within its scope shall be subject to the constraints of the present invention.

Claims

1. Double-drive multi-fingered bionic gripper, characterized by: The gripper comprises a frame, a first motor (1) for driving the frame to rotate around an axis, a second motor (11) arranged in the frame, a support platform (8) telescopically positioned at the front end of the frame, a plurality of gripper branches arranged around the support platform, and a transmission mechanism for transmitting power from the second motor to drive the support platform and the gripper branches to move; The transmission mechanism comprises a guide rail (9) arranged in the frame and parallel to the length direction of the frame, a push plate (13) that can slide along the guide rail, a screw rod (12) driven by a second motor, and a nut that meshes with the screw rod and is fixed on the push plate; the support platform can be slidably positioned on the guide rail, and a plurality of connecting blocks (14) are provided on the support platform, and the connecting blocks are connected to the push plate via an elastic body (20); The gripper branch is a quadrilateral mechanism formed by sequentially hinged connection of a first connecting rod (15), a second connecting rod (16), a third connecting rod (17) and a fourth connecting rod (18), wherein the first connecting rod is rotatably hinged on the connecting block, the third connecting rod is rotatably hinged on the frame, and the fourth connecting rod is provided with a fifth connecting rod (19); In the gripper branch, one end of the first connecting rod is rotatably hinged on the connecting block, two ends of the third connecting rod are respectively rotatably hinged on the middle part of the first connecting rod and one end of the fourth connecting rod, the middle part of the third connecting rod is rotatably hinged on the frame, and two ends of the second connecting rod are respectively rotatably hinged on the other end of the first connecting rod and the other end of the fourth connecting rod; The fifth connecting rod is fixed to one end of the fourth connecting rod close to the third connecting rod, the fifth connecting rod is curved and the portion of the third connecting rod between the frame and the fourth connecting rod is curved; The rack comprises a first rack plate (6), a rack platform (4), a second rack plate (7), a plurality of first rack rods (3) fixed between the first rack plate and the rack platform, and a plurality of second rack rods (10) fixed between the rack platform and the second rack plate.

2. The dual-drive multi-joint bionic gripper according to claim 1, characterized in that: The first motor is arranged at the rear end of the frame, and the rotating shaft of the first motor is fixed to the frame through a coupling.

3. The dual-drive multi-joint bionic gripper according to claim 2, characterized in that: The second motor is fixed in the frame platform; the guide rail is arranged between the frame platform and the second frame plate and is fixed to the frame platform; the guide rail is a hollow cylinder, and a plurality of slide grooves (9.1) arranged along the busbar direction are provided on the guide rail.

4. The dual-drive multi-joint bionic gripper according to claim 3, characterized in that: The push plate comprises a first plate body (13.1) and second plate bodies (13.2) radially arranged around the first plate body, the first plate body being located in the inner cavity of the guide rail, the second plate body being slidably matched with the slide groove and the second plate body passing through the slide groove and extending outside the guide rail.

5. The dual-drive multi-joint bionic gripper according to claim 4, characterized in that: The support platform is a hollow cylinder slidably mounted on the guide rail, and a through hole (7.1) is provided at the center of the second frame plate for the movement of the support platform.

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