Multi-mode fusion bionic coating gripper based on chameleon hunting mechanism

Abstract

The invention discloses a multi-mode fusion bionic coating gripper based on a chameleon hunting mechanism, and belongs to the technical field of bionic robots. The linear driver is embedded in the shell, and the upper end of the linear driver is fixedly connected with the shell; the flexible film is in a hollow hemisphere shape, the center of the flexible film is provided with a concave part, the concave part is connected with the lower end of the linear driver from the inside, and the outside of the flexible film is connected with the shell to form a closed space; the electro-adsorption film is attached to the surface of the flexible film; one of the two mutually independent air passages is communicated with the linear actuator and used for controlling the linear actuator to move, the other air passage is communicated with the closed space and used for controlling the flexible film to deform, and the deformation of the linear actuator and the flexible film is controlled by changing the air pressure in the two air passages so as to envelop or adsorb an object. According to the method, objects of various shapes and sizes are completely wrapped in an enveloping space in a self-adaptive mode, and the requirement for modeling of specific form information of the objects is eliminated.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of bionic robots, and particularly relates to a multi-mode fusion bionic wrapping gripper based on the hunting mechanism of a chameleon. BACKGROUND

[0002] The successful grasping of objects of various shapes, sizes and hardness in a non-structured environment has always been one of the scientific problems that must be overcome for robots to achieve integration with people and the environment. Because the target to be operated is uncertain in different scenarios, an end effector that can adapt to different types of objects is urgently needed to improve the intelligent operation capability of the robot.

[0003] In a non-structured environment, there are many types of objects and uncertain postures, and it is extremely challenging for a robot to successfully grasp them. The key bottlenecks include: (1) For the differences in object size and shape, it is necessary to model tens of thousands of objects to solve the grasping point, the grasping process is complex, and the configuration space of the multi-fingered gripper is limited, so the adaptability to different shaped objects still needs to be improved; (2) For the differences in object weight and hardness, the use of a rigid gripper requires force feedback to ensure grasping safety, and the use of a soft gripper is insufficient in load capacity, so it is difficult for the same gripper to have high safety and high load. How to reduce the dependence of the grasping task on information such as object shape, size and hardness, and achieve simple and efficient adaptive grasping is a forward-looking thought.

[0004] Exploring and learning from the bionic grasping concept of the chameleon's tongue self-adaptive wrapping and multi-mode fusion hunting mechanism is an effective way to break through the above challenges. After millions of years of evolution, the chameleon has provided mankind with a lot of valuable knowledge for exploring natural science, but current research mainly focuses on its color-changing camouflage function and high-speed ejection function of the tongue, and relatively less on its tongue hunting function. Through research, it is found that the hunting of a chameleon is divided into three processes: positioning, attaching and complete wrapping, during which the tongue tip gradually forms an internal cavity, and the prey is continuously "rolled" into the internal cavity and forms a geometric interlocking with the tongue. If the deformation wrapping mechanism of the chameleon's tongue can be revealed and applied to robot grasping, the gripper will achieve all-around wrapping of the object, and the adaptability to the object shape and size will be greatly improved. Although the chameleon's tongue is very soft, it can use geometric interlocking and secreted mucus to grasp heavier prey. Professor Herrel, an internationally renowned chameleon researcher, pointed out that the chameleon can also generate negative pressure through muscle traction to increase the grasping force, so it can grasp prey of different weights.

[0005] Therefore, a multi-mode fusion bionic wrapping gripper based on the hunting mechanism of a chameleon is urgently needed. SUMMARY

[0006] To achieve the above purpose, the application adopts the following technical solutions:

[0007] A multi-mode fusion bionic clamping device based on the hunting mechanism of chameleons, comprising:

[0008] A shell;

[0009] A linear driver embedded in the interior of the shell, with its upper end fixedly connected to the shell;

[0010] A flexible film in the shape of a hollow hemisphere, with a recess in its center, connected to the lower end of the linear driver from the inside, and its outer part connected to the shell, forming a closed space;

[0011] An electro-adsorption film attached to the surface of the flexible film, in the form of a thin film;

[0012] Two independent air channels, one of which is connected to the linear driver for controlling its movement, and the other is connected to the closed space for controlling the deformation of the flexible film, by changing the air pressure in the two channels to control the deformation of the linear driver and the flexible film, to achieve the enveloping or adsorbing of objects.

[0013] Further, the electro-adsorption film includes an electro-adsorption pattern positive electrode and an electro-adsorption pattern negative electrode, which are concentric circles arranged in an alternating manner but with their ends disconnected, and are respectively connected to an external power source through the outermost lead wires.

[0014] Further, the lower end of the flexible film is fixed to the linear driver by vulcanized glue, the outer ring of the flexible film is fixed to the shell by a strap, and the upper end of the linear driver is fixed to the shell by a bolt.

[0015] Further, the shell is a resin shell, with a resin cover fixedly connected to the end away from the flexible film.

[0016] Further, the linear driver includes:

[0017] A TPU woven composite film in the shape of a cylinder;

[0018] A plurality of 3D printed discs arranged longitudinally and equidistantly inside the TPU woven composite film, serving as the skeleton support of the TPU woven composite film;

[0019] An upper end connector fixedly connected to the uppermost 3D printed disc;

[0020] A lower end connector fixedly connected to the lowermost 3D printed disc.

[0021] Further, the 3D printed disc is a PLA rigid disc inlaid with a TPU ring.

[0022] Further, the outer periphery of the 3D printed disc is connected and sealed with the TPU fabric composite film by means of heating welding.

[0023] Further, the upper end connector is fixed with the shell by bolts, the lower end connector is fixed with the flexible film by vulcanization glue, and the outer circle of the flexible film is fixed with the shell by a strap.

[0024] Further, the 3D printed disc is provided with six.

[0025] Further, the gripper includes five gripping modes:

[0026] The first mode is that the gripper is displaced downward to cover the object, negative pressure is applied to the linear drive to make the linear drive shrink, so as to drive the flexible film to move upward and pull the object to move inward.

[0027] The second mode is that negative pressure is applied to the linear drive to make the linear drive shrink and negative pressure is applied to the flexible film, so as to drive the flexible film to move upward and expand outward to form a cavity, the gripper is displaced downward to preliminarily contact the object, and then positive pressure is applied to the flexible film to make the formed cavity shrink inward to cover and grasp the object.

[0028] The third mode is that the gripper is displaced downward to cover the object, positive pressure is applied to the flexible film to make the flexible film shrink inward to grasp the object, and then negative pressure is applied to the linear drive to make the linear drive shrink, so as to drive the flexible film to move upward and swallow the object.

[0029] The fourth mode is that positive pressure is first applied to the flexible film to make the flexible film on the gripper closely adhere to the surface of the object to form a closed space, and then negative pressure is applied to the linear drive, the linear drive drives the flexible film to move upward to reduce the air pressure of the closed space and form negative pressure to adsorb the object.

[0030] The fifth mode is that the flexible film is attached to the surface of the object, and the electro-adsorptive film is electrified to adsorb the object by using the electro-adsorptive film.

[0031] Beneficial effects:

[0032] The present application can completely cover any shape and size object in the envelope space, and can eliminate the need for modeling specific shape information of the object.

[0033] The present application can increase the load by several times while ensuring safety with soft materials, and can not damage the grasped object without force control.

[0034] The present application learns from the morphing enveloping mechanism of chameleons, so that the gripper can automatically adapt to and envelop objects of any shape in all directions within the envelope space without relying on detailed shape information of the object, by using the deformation of structure and material; learns from the high gripping force mechanism of multi-mode fusion of geometric interlocking, electrostatic adhesion and negative pressure adhesion, so that the gripper can not only use soft materials to ensure safety during gripping, but also can increase the gripping force by several times, and has high safety and high load capacity, thus getting rid of the need for force control from the safety point of view. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 It is an overall structure explosion schematic diagram of the gripper in the present application.

[0036] Figure 2 It is an overall structure schematic diagram of the linear driver in the present application.

[0037] Figure 3 It is a schematic diagram of the electro-adsorption film in the present application.

[0038] Figure 4 It is a first mode flowchart of the gripped object in the present application.

[0039] Figure 5 It is a second mode flowchart of the gripped object in the present application.

[0040] Figure 6 It is a third mode flowchart of the gripped object in the present application.

[0041] Figure 7 It is a fourth mode flowchart of the gripped object in the present application.

[0042] Figure 8 It is a fifth mode flowchart of the gripped object in the present application.

[0043] 1, resin cover; 2, shell; 3, linear driver; 4, flexible film; 5, electro-adsorption film; 6, upper end connecting piece; 7, TPU woven cloth composite film; 8, 3D printed disc; 9, lower end connecting piece; 10, electro-adsorption pattern positive electrode; 11, electro-adsorption pattern negative electrode. DETAILED DESCRIPTION

[0044] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0045] This part will describe the specific embodiments of the present application in detail, and the preferred embodiments of the present application are shown in the accompanying drawings, and the role of the drawings is to supplement the description of the text part with graphics, so that people can intuitively and visually understand each technical feature and the overall technical scheme of the present application, but it cannot be understood as a limitation on the protection scope of the present application.

[0046] In the description of the present application, it should be understood that the orientation description, such as the orientation or positional relationship indicated by the upper, lower, front, rear, left, right, etc. based on the orientation or positional relationship shown in the drawings, is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0047] In the description of the present application, one or more is meant to be one or more, more than two is meant to be two or more, greater than, less than, more than, etc. are understood to not include the number, above, below, etc. are understood to include the number. If the first, second is described, it is only for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated or the order of technical features indicated.

[0048] In the description of the present application, unless otherwise explicitly limited, the words such as setting, mounting, connecting, etc. should be broadly understood, and those skilled in the art can reasonably determine the specific meaning of the above words in the present application in combination with the specific content of the technical solution.

[0049] Embodiment 1

[0050] Reference Figures 1-3 A multi-mode fusion bionic clamping device based on the hunting mechanism of a chameleon, comprising:

[0051] A shell 2;

[0052] A linear driver 3 is embedded in the inside of the shell 2, and the upper end of the linear driver 3 is fixedly connected with the shell 2;

[0053] A flexible film 4 is in a hollow hemispherical shape, the center of the flexible film 4 is provided with a recess, the recess is connected with the lower end of the linear driver 3 from the inside, and the outside of the flexible film 4 is connected with the shell 2 to form a closed space;

[0054] An electro-adsorption film 5 is attached to the surface of the flexible film 4, and the electro-adsorption film 5 is a thin film structure;

[0055] Two independent air channels, one of which is in communication with the linear driver 3 for controlling the movement of the linear driver 3, and the other is in communication with the closed space for controlling the deformation of the flexible film 4, by changing the air pressure in the two air channels through mutual cooperation, the deformation of the flexible film 4 is controlled to realize the enveloping or adsorbing of the object.

[0056] In this embodiment, because the linear driving end is connected with the flexible film, when the linear driver is retracted, it can drive the flexible film to deform and form a cavity.

[0057] In the embodiment, the electro-adsorption film 5 comprises an electro-adsorption pattern positive electrode 10 and an electro-adsorption pattern negative electrode 11, which are concentric circles arranged in staggered manner but with the ends disconnected, and are connected to an external power source through the outermost lead wires.

[0058] In implementation, the electro-adsorption film 5 is printed with electro-adsorption patterns on a silica gel film by screen printing, and then a silica gel film is laid on it for packaging.

[0059] In implementation, under the action of a high-voltage direct-current power source, the electro-adsorption film can polarize the electrons on the surface of an object, thereby generating an adsorption force on the object.

[0060] In the embodiment, the flexible film 4 is fixed to the lower end of the linear actuator 3 by vulcanized glue, the outer ring of the flexible film 4 is fixed to the shell 2 by a cable tie, and the upper end of the linear actuator 3 is fixed to the shell 2 by a bolt.

[0061] In implementation, the upper end of the linear actuator is connected to the shell by a bolt, a silica gel gasket, and the shell.

[0062] In the embodiment, the shell 2 is a resin shell 2, and the resin shell 2 is fixedly connected to the resin cover 1 at the end away from the flexible film 4.

[0063] In the embodiment, the flexible film 4 is formed by silica gel casting.

[0064] In implementation, the side of the flexible film 4 is fixed to the shell, the upper end is connected to the linear actuator 3, and under the action of the air pressure in the inner cavity, the flexible film 4 can be contracted to form a cavity or envelope an object.

[0065] Embodiment 2

[0066] In order to improve the practicability, the embodiment makes further settings on the basis of Embodiment 1.

[0067] In the embodiment, the linear actuator 3 comprises:

[0068] a TPU woven composite film 7 in the shape of a cylinder;

[0069] a plurality of 3D printed discs 8 arranged in the interior of the TPU woven composite film 7 in longitudinal equidistant manner, serving as the skeleton support of the TPU woven composite film 7;

[0070] an upper end connecting piece 6 fixedly connected to the uppermost 3D printed disc 8;

[0071] a lower end connecting piece 9 fixedly connected to the lowermost 3D printed disc 8.

[0072] In the embodiment, the 3D printed disc 8 is a PLA rigid disc inlaid with a TPU ring.

[0073] In the embodiment, the 3D printed disc 8 is provided with six.

[0074] In the embodiment, the linear driver is in the shape of a cylinder as a whole, the inside of the TPU woven composite film 7 has six PLA rigid discs inlaid with TPU rings as a framework support, and the two ends are fixed by using aluminum connecting pieces, so as to facilitate the connection and fixation with other modules of the gripper.

[0075] In the embodiment, the aluminum upper end connecting piece is connected with the uppermost 3D printed disc by using a bolt, and the aluminum lower end connecting piece is connected with the lowermost 3D printed disc by using a bolt.

[0076] In the embodiment, the linear driver has an opening at the upper part, can be connected with a corresponding air duct, and can perform linear displacement under the action of air pressure, so as to realize shortening or lengthening.

[0077] In the embodiment, the outer periphery of the 3D printed disc 8 is connected and sealed with the TPU woven composite film 7 by using a heating welding method.

[0078] In the embodiment, the upper end connecting piece 6 is fixed with the shell 2 by using a bolt, the lower end connecting piece 9 is fixed with the flexible film 4 by using vulcanization glue, and the outer ring of the flexible film 4 is fixed with the shell 2 by using a strap.

[0079] The present application learns from the deformation covering mechanism of the chameleon tongue, so that the gripper can automatically adapt to and cover an object of any shape in an envelope space without relying on detailed shape information of the object by using the deformation of structure and material; learns from the high gripping force mechanism of the multi-mode fusion of geometric interlocking, electrostatic adhesion and negative pressure adhesion, so that the gripper can not only use soft material to ensure the safety of gripping, but also can increase the gripping force by several times, and has high safety and high load capacity, thereby getting rid of the demand for force control from the safety point of view.

[0080] Embodiment 3

[0081] Reference Figures 4-8 The embodiment provides a gripper including five gripping modes.

[0082] The first mode is that the gripper is displaced downward to cover the object, negative pressure is applied to the linear driver, so that the linear driver 3 is contracted, thereby driving the flexible film 4 to move upward and pull the object to move inward;

[0083] The second mode is that negative pressure is applied to the linear driver, so that the linear driver 3 is contracted and negative pressure is applied to the flexible film 4, thereby driving the flexible film 4 to move upward and expand outward to form a cavity, the gripper is displaced downward to preliminarily contact the object, and then positive pressure is applied to the flexible film, so that the formed cavity is contracted inward to cover and grip the object.

[0084] The third mode is that the gripper displaces the coated object downward, applies positive pressure to the flexible film 4 to make the flexible film 4 contract inward, grabs the object, and then applies negative pressure to the linear drive to make the linear drive 3 contract, thereby driving the flexible film 4 to move upward and swallow the object into it;

[0085] The fourth mode is that positive pressure is first applied to the flexible film 4 to make the flexible film 4 on the gripper closely adhere to the surface of the object to form a closed space, and then negative pressure is applied to the linear drive, which drives the flexible film 4 to move upward to make the air pressure in the closed space decrease to form negative pressure to adsorb the object;

[0086] The fifth mode is that the flexible film 4 is attached to the surface of the object, and the electro-adsorption film 5 is electrified to adsorb the object by using the electro-adsorption film 5.

[0087] The above is only the preferred embodiment of the present application, and does not limit the technical scope of the present application in any way. Any slight modification, equivalent change and modification made to the above embodiment according to the technical essence of the present application still falls within the scope of the technical solution of the present application.

Claims

1. A multi-mode fusion bionic coated gripper based on the chameleon hunting mechanism, characterized by: include: shell; A linear driver, wherein the linear driver is embedded in the interior of the housing, and the upper end of the linear driver is fixedly connected to the housing; a flexible membrane, wherein the flexible membrane is in a hollow hemispherical shape, a recessed portion is provided at the center of the flexible membrane, the recessed portion is internally connected to the lower end of the linear actuator, and the exterior of the flexible membrane is connected to the housing to form a closed space; An electro-adsorption film, wherein the electro-adsorption film is attached to the surface of the flexible film and has a thin film structure; Two independent air channels, one of which is connected to the linear drive to control the movement of the linear drive, and the other air channel is connected to the confined space to control the deformation of the flexible membrane. By cooperating with each other to change the air pressure in the two air channels, the deformation of the linear drive and the flexible membrane is controlled to achieve enveloping or adsorbing objects.

2. The multi-mode fusion bionic coated gripper based on the chameleon hunting mechanism according to claim 1 is characterized in that: The electrosorption film includes an electrosorption pattern positive electrode and an electrosorption pattern negative electrode. The electrosorption pattern positive electrode and the electrosorption pattern negative electrode are concentric circles that are staggered but disconnected at the ends and are respectively connected to an external power supply through outermost leads.

3. The multi-mode fusion bionic coated gripper based on the chameleon hunting mechanism according to claim 1 is characterized in that: The flexible membrane and the lower end of the linear actuator are fixed by vulcanized glue, the outer ring of the flexible membrane and the shell are fixed by a cable tie, and the upper end of the linear actuator and the shell are fixed by bolts.

4. The multi-mode fusion bionic coated gripper based on the chameleon hunting mechanism according to claim 1 is characterized in that: The housing is a resin housing, and one end of the resin housing away from the flexible film is fixedly connected with a resin cover.

5. The multi-mode fusion bionic coated gripper based on the chameleon hunting mechanism according to claim 1 is characterized in that: The linear drive comprises: Cylindrical TPU woven composite film; A plurality of 3D printed discs are longitudinally arranged at equal intervals inside the TPU woven composite film to serve as a skeleton support for the TPU woven composite film; An upper connecting piece, the upper connecting piece being fixedly connected to the uppermost 3D printing disc; A lower end connecting piece is fixedly connected to the 3D printing disc located at the bottom.

6. The multi-mode fusion bionic coated gripper based on the chameleon hunting mechanism according to claim 5 is characterized in that: The 3D printed disc is a PLA rigid disc inlaid with a TPU ring.

7. The multi-mode fusion bionic coated gripper based on the chameleon hunting mechanism according to claim 6 is characterized in that: The outer periphery of the 3D printed disc is connected and sealed to the TPU woven composite film by means of heating and welding.

8. The multi-mode fusion bionic coated gripper based on the chameleon hunting mechanism according to claim 5 is characterized in that: The upper end connecting piece is fixed to the shell by bolts, the lower end connecting piece is fixed to the flexible membrane by vulcanized glue, and the outer ring of the flexible membrane is fixed to the shell by a cable tie.

9. The multi-mode fusion bionic coated gripper based on the chameleon hunting mechanism according to claim 5 is characterized in that: There are 6 3D printing discs provided.

10. The multi-mode fusion bionic coated gripper based on the chameleon hunting mechanism according to claim 1 is characterized in that: The gripper includes five gripping modes: In the first mode, the gripper moves downward to wrap around the object, applying negative pressure to the linear actuator to cause it to contract, thereby moving the flexible membrane upward and pulling the object inward. The second mode involves applying negative pressure to the linear actuator to cause it to contract and apply negative pressure to the flexible membrane, which in turn drives the membrane upward and expands outward to form a cavity. The gripper then moves downward to initially contact the object, and then positive pressure is applied to the flexible membrane, causing the formed cavity to contract inward, enveloping the grasped object. The third mode is: the gripper moves downward to wrap around the object, applying positive pressure to the flexible membrane, causing it to contract inward and grasp the object. Then, negative pressure is applied to the linear drive to contract the linear drive, driving the flexible membrane upward to engulf the object. The fourth mode is: first, positive pressure is applied to the flexible membrane so that the flexible membrane on the gripper is tightly attached to the surface of the object, forming a confined space. Then, negative pressure is applied to the linear drive, which drives the flexible membrane upward, reducing the air pressure in the confined space, forming negative pressure, and adsorbing the object. The fifth mode is: stick the flexible film on the surface of the object, energize the electro-adsorption film, and use the electro-adsorption film to adsorb the object.

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