CN108406839B

CN108406839B - Integrated artificial joint based on laser local modification and application thereof

Info

Publication number: CN108406839B
Application number: CN201810167320.4A
Authority: CN
Inventors: 孙洪波; 张永来; 韩冰
Original assignee: Jilin University
Current assignee: Jilin University
Priority date: 2018-02-28
Filing date: 2018-02-28
Publication date: 2021-06-18
Anticipated expiration: 2038-02-28
Also published as: CN108406839A

Abstract

The invention discloses an integrated artificial joint based on laser local modification and application thereof, belonging to the technical field of flexible robots. The artificial joint is of a one-piece hand-shaped double-layer thin film structure and consists of a joint driver and a muscle supporting area; the joint driver comprises a lower light-driven trigger layer and an upper polymer film, and is positioned at the corresponding finger joint position designed by a human hand; the muscle support area comprises a lower light-driven non-trigger layer and an upper polymer film.

Description

Integrated artificial joint based on laser local modification and application thereof

Technical Field

The invention belongs to the technical field of flexible robots, and particularly relates to an optically-driven integrated artificial joint formed by a reduced graphene oxide/gold nanorod composite film and a polymer film, wherein a plurality of artificial joints are independently and flexibly driven by laser, so that a flexible manipulator with basic functions of hands is realized.

Technical Field

Flexible robots are an important branch of robots. Compared with the traditional robot made of rigid materials such as metal and the like, the flexible robot has the advantages of being easy to deform (bend, fold, expand and the like), easy to recover, good in adaptability to various working environments, safe to a human body and the like. It can be seen that the flexible robot has significant complementarity to the traditional robot in characteristics and functions, and can cover and fill up many limited application fields of the traditional robot, including biomedical, sensor and bionics.

At present, the materials for processing the flexible robot mainly comprise hydrogel, polymer, artificial rubber and other flexible materials. In order to realize the most basic movement and various mechanical functions of the flexible robot, the available external driving force can be single stimulation or even double stimulation such as electricity, magnetism, light, heat, humidity and the like. However, considering the freedom of movement of each component part of the robot and the corresponding complexity of the various basic mechanical functions, achieving independent control of these parts means that a large number of drives must be loaded and controlled one by one. For example, in the case of the most common robot arm type robot, it is necessary to provide actuators (at least 15) at each phalangeal joint and perform independent actuation control, so as to achieve the most basic movements and functions (finger movement, bending, grasping, etc.) similar to the human hand. The existing flexible robot technology mostly adopts the technical scheme that drivers are arranged at nodes or parts needing to be controlled one by one, and then all the drivers are communicated through a passage (a circuit or an air passage) and are subjected to centralized driving control. The flexible robot based on the driver-channel design often has the problems of complex structure, inflexible control, complex process and the like, and is difficult to solve by utilizing the prior art.

Disclosure of Invention

Aiming at the defects of the prior art, the technical problems to be solved by the invention are as follows: an integrated artificial joint based on laser local modification is provided. The double-layer thin film formed by the graphene oxide/gold nanorod composite thin film and the polymer thin film is used as a muscle tissue-like raw material of the flexible manipulator, and the graphene oxide at each phalangeal joint of the manipulator is locally modified and reduced by laser, so that the double-layer thin films at the joints are directly converted into optical drivers, a plurality of integrated artificial joints which can be independently optically driven are obtained, and the basic motion and mechanical function control of the flexible manipulator is realized.

The invention is realized by the following technical scheme:

an integrated artificial joint based on laser local modification is of a one-piece hand-shaped double-layer thin film structure and comprises a joint driver 1 and a muscle support area 2;

the joint driver 1 comprises a lower light-driven trigger layer 3 and an upper polymer film 5, is positioned at a corresponding knuckle position designed by a human hand and is used for controlling the movement and deformation of each flexible mechanical finger;

the muscle support region 2 comprises a lower light-driven non-triggering layer 4 and an upper polymer film 5, and plays a role in supporting, connecting and integrating artificial muscles of the joint drivers 2.

Further, the optical drive non-trigger layer 4 is a graphene oxide/gold nanorod composite film, the optical drive trigger layer 3 is a reduced graphene oxide/gold nanorod composite film obtained through laser local modification, the mass ratio of the graphene oxide to the gold nanorods in the optical drive trigger layer 3 and the optical drive non-trigger layer 4 is 3.25:1-8.12:1, the film thickness of the optical drive trigger layer 3 is 1-2 μm, and the film thickness of the optical drive non-trigger layer 4 is 2-10 μm.

Further, the polymer film 5 is made of polymethyl methacrylate (PMMA) and has a film thickness of 10-50 μm.

Further, the number of the joint drivers 1 is 14-22, and the joint drivers are respectively positioned at the joints of the five fingers.

The invention also provides application of the integrated artificial joint based on laser local modification in the aspects of forming and controlling the flexible manipulator, namely, the basic motion and grabbing functions of the fingers of the flexible manipulator are realized by independently driving the integrated artificial joints.

Compared with the prior art, the invention has the following advantages:

(1) the optical driver is directly generated and integrated at the joint position of the artificial muscle by utilizing laser local modification, so that the preparation process and the flexible robot structure are greatly simplified;

(2) and a laser beam is adopted to control the independent control of one joint, so that the flexible robot is controlled more directly, quickly and flexibly.

Drawings

FIG. 1 is a schematic structural diagram of an integrated artificial joint based on laser local modification according to the present invention;

in the figure: the joint driving device comprises a joint driver 1, a muscle supporting area 2, a light-driven triggering layer 3, a light-driven non-triggering layer 4 and a polymer film 5;

FIG. 2 is a human-like hand schematic of an assembled flexible manipulator of the present invention;

FIG. 3 is a pictorial view of an assembled flexible manipulator of the present invention;

FIG. 4 is a single-beam laser-induced kinegram of an integrated artificial joint based on laser local modification according to the present invention;

wherein, the (a) - (d) are sequentially the second joints of the light-driven index finger, the middle finger, the ring finger and the little finger;

fig. 5 is a schematic diagram of two laser drives of an integrated artificial joint based on laser local modification according to the present invention.

Detailed Description

The technical scheme of the invention is further specifically described below by combining the attached drawings.

Example 1

As shown in figure 1, the invention provides an integrated artificial joint based on laser local modification, which comprises a joint driver 1 and a muscle support area 2; the whole artificial joint is of a hand-shaped double-layer thin film structure;

the joint driver 1 comprises a lower light-driven trigger layer 3 and an upper polymer film 5; when driven by light, the light-driven trigger layer 3 and the polymer film 5 generate photothermal response and expand, and the expansion coefficient of the polymer film 5 is far greater than that of the light-driven trigger layer 3, so that the joint driver 1 bends downwards; the optical drive trigger layer 3 plays a role in enhancing light absorption and improving light response speed;

the muscle support area 2 comprises a lower light-driven non-trigger layer 4 and an upper polymer film 5, and plays a role in supporting, connecting and integrating each joint driver;

the optical drive non-trigger layer 4 is a graphene oxide/gold nanorod composite film, and the optical drive trigger layer 3 is a reduced graphene oxide/gold nanorod composite film obtained through laser local modification.

Example 2

The integrated artificial joint based on laser local modification is driven by a single laser beam.

According to the integrated artificial joint provided by the invention, the plurality of optical drivers are directly integrated to the joint position of the flexible manipulator by using a laser local modification method, and the joint drivers are driven in a one-to-one correspondence mode by using laser, so that the driving flexibility is greatly improved.

The method for driving the integrated artificial joint based on laser local modification by using single laser comprises the following specific steps:

(1) assembling the flexible manipulator;

the method comprises the following specific steps: the number of the joint drivers on the integrated artificial joints is 14, the joint drivers are respectively positioned at the joints of the phalanges, the flexible manipulator bones are obtained by cutting PDMS (polydimethylsiloxane) films by laser, the thickness of the flexible manipulator bones is 2mm, and the flexible manipulator bones comprise 14 discrete phalanges and 1 integrated metacarpal bone and carpal bone; adhering each hand bone to a corresponding position above a muscle supporting area of the hand-shaped artificial joint according to the structure of a hand, and finishing the assembly of the flexible manipulator;

(2) single-beam laser driving joint driver:

the method comprises the following specific steps: the thickness of the optical drive trigger layer 3 of the used artificial joint is 2 μm, the thickness of the optical drive non-trigger layer 4 is 1 μm, and the thickness of the polymer film 5 is 10 μm. The light driving light source is a carbon dioxide laser with the wavelength of 808 nm; the laser light spot is hit to the joint driver to be driven, the joint is bent, and the corresponding finger is driven to bend.

As shown in fig. 2 and 3, the flexible manipulator designed by simulating a human hand may have a skeleton portion composed of 14 discrete phalanges and an integrated metacarpal bone and carpal bone, and then the skeletons are adhered to hand-shaped integrated artificial joints with similar sizes according to the structural design, so as to obtain a flexible manipulator with a centimeter magnitude.

As can be seen from fig. 4, the second finger joints of the index finger, the middle finger, the ring finger and the little finger of the flexible manipulator are optically driven by using a single laser beam in sequence, so that the corresponding fingers are rapidly bent and deformed, which indicates that the integrated artificial joint based on laser local modification has a high-efficiency optical driving effect.

Example 3

Two beams of laser are utilized to drive the integrated artificial joint based on laser local modification.

Each joint driver of the integrated artificial joint based on laser local modification has one-to-one light driving characteristic which can be independently controlled, and complex design of channels and centralized control is not needed. As long as a plurality of laser light sources are provided to respectively drive and control the joint drivers with corresponding numbers, more deformation and even mechanical functions of the flexible manipulator can be realized.

The method for driving the integrated artificial joint based on laser local modification by using two beams of laser comprises the following specific steps:

(1) assembling the flexible manipulator: the procedure and parameters were as in example 1; the thickness of the light-driven trigger layer 3 of the used artificial joint is 10 mu m, the thickness of the light-driven non-trigger layer 4 is 2 mu m, and the thickness of the polymer film 5 is 50 mu m.

(2) The light driving light source is two carbon dioxide lasers with the wavelength of 808nm, and the two carbon dioxide lasers respectively provide two beams of laser light; the two laser light spots are respectively hit to the joint drivers to be driven, and the joints are bent to drive the corresponding fingers to bend.

As can be seen from fig. 5, the two knuckles of one finger can be optically driven by two laser beams, so that both knuckle drivers are bent, and finally the finger is in a bent state for gripping. Therefore, two or even multiple beams of laser are adopted to respectively drive the joint drivers, and various flexible and complex mechanical functions of the flexible manipulator are expected to be realized.

Claims

1. An integrated artificial joint based on laser local modification is characterized in that the artificial joint is of a one-piece hand-shaped double-layer thin film structure and consists of a joint driver (1) and a muscle support area (2);

the joint driver (1) comprises a lower light-driven trigger layer (3) and an upper polymer film (5), and is positioned at a corresponding finger joint position designed by a human hand and used for controlling the movement and deformation of each flexible mechanical finger;

the muscle support area (2) comprises a lower light-driven non-trigger layer (4) and an upper polymer film (5), and plays a role in supporting, connecting and integrating artificial muscles of all joint drivers (1);

the optical drive non-trigger layer (4) is a graphene oxide/gold nanorod composite film, the optical drive trigger layer (3) is a reduced graphene oxide/gold nanorod composite film obtained through laser local modification, the mass ratio of the graphene oxide to the gold nanorods in the optical drive trigger layer (3) and the optical drive non-trigger layer (4) is 3.25:1-8.12:1, the film thickness of the optical drive non-trigger layer (4) is 1-2 mu m, and the film thickness of the optical drive trigger layer (3) is 2-10 mu m.

2. The integrated artificial joint based on laser local modification of claim 1, wherein the polymer film (5) is made of polymethyl methacrylate and the film thickness is 10-50 μm.

3. The integrated artificial joint based on laser local modification as claimed in claim 1, characterized in that the number of the joint drivers (1) is 14-22, and the drivers are respectively positioned at the joints of five fingers.

4. Use of an integrated artificial joint based on laser local modification according to claim 1.