Artificial muscle device with multiple contraction modes

Abstract

The invention discloses an artificial muscle device with multiple contraction modes, the artificial muscle comprises a plurality of variable limiters and rigid-flexible coupling rings, the variable limiters are arranged at intervals and can be buckled with each other, each variable limiter is of a structure with a similar negative Poisson's ratio function, is in a closed ring shape and comprises two end plates and two bent rods which are parallel to each other, and the rigid-flexible coupling rings are connected with the two end plates and the two bent rods. The bent rods can be further deformed, a transverse pull rope is arranged between the two bent rods, a longitudinal pull rope is arranged between the two rigid-flexible coupling rings in the variable limiter, and the transverse pull rope and the longitudinal pull rope are both made of photosensitive or thermosensitive liquid crystal elastomers and can be properly contracted under the action of illumination or a heat source. And the plurality of transverse pull ropes and the plurality of longitudinal pull ropes can be independently controlled and have different shrinkage amounts, so that the fine control on the artificial muscle is realized.

Description

Technical Field

[0001] The present invention relates to an artificial muscle device with multiple contraction modes and a control method thereof, which can simulate different forms of muscle movements and is particularly suitable for the development of bionic flexible robots, and has an important technical support role and broad application prospects. Background Art

[0002] In nature, the movement of bones usually relies on the coordinated action of antagonist muscles and agonist muscles. Taking the flexion and extension of the elbow joint as an example, the biceps and triceps act as antagonist muscles and agonist muscles respectively, and control is achieved by contraction and extension. This fine coordination of paired muscles can not only provide the power of movement, but also accurately control the speed and stability of movement. The movement patterns of muscles mainly include concentric contraction, isometric contraction and eccentric contraction:

[0003] Concentric contraction: The form of movement produced by muscle shortening, which is the main way of force output;

[0004] Isometric contraction: The muscle exerts force while maintaining its length, used to maintain posture or structural stability.

[0005] Eccentric contraction: The muscle gradually lengthens under the action of external force, which is used to control the deceleration and balance of movement.

[0006] In the field of artificial muscles, especially when achieving eccentric contraction, significant technical challenges are still faced. Currently, existing artificial muscle fibers usually achieve contraction by changing the internal structure of the material, but this structure will suffer irreversible damage during eccentric contraction. This damage not only affects the durability of artificial muscles, but also severely limits the accuracy and stability of their movement. Therefore, achieving eccentric contraction without damaging the material structure has become the key to improving the performance of artificial muscles. This is crucial for the application of flexible robots and smart wearable devices, as these devices need to maintain efficient and stable performance in multiple motion modes.

[0007] In view of the above problems, the inventors have conducted in-depth research on methods for achieving non-destructive eccentric contraction, in the hope of designing an artificial muscle device with multiple contraction modes that can solve the above problems. Summary of the invention

[0008] In order to overcome the above-mentioned problems, the inventors have conducted intensive research and designed an artificial muscle device with multiple contraction modes, wherein the artificial muscle includes a plurality of variable limiters and rigid-flexible coupling rings that are arranged at intervals and can be buckled with each other, wherein the variable limiter is a structure having a function similar to that of a negative Poisson's ratio, and is in the shape of a closed ring, comprising two end plates and two curved rods parallel to each other, wherein the curved rods can be further deformed, and a transverse pull rope is arranged between the two curved rods, and in the variable limiter, a longitudinal pull rope is arranged between the two rigid-flexible coupling rings, and both the transverse pull rope and the longitudinal pull rope are made of photosensitive or thermosensitive liquid crystal elastomers, and can contract moderately under the action of light or heat source, thereby controlling the overall contraction of the artificial muscle, and the plurality of transverse pull ropes and longitudinal pull ropes can be independently controlled, and have different contraction amounts, thereby achieving fine control of the artificial muscle, thereby completing the present invention.

[0009] Specifically, the purpose of the present invention is to provide an artificial muscle device with multiple contraction modes, the artificial muscle comprising a variable limiter 1, a rigid-flexible coupling ring 2 and an intelligent material; the variable limiter 1 is used to maintain stability and withstand external forces in different motion modes; the rigid-flexible coupling ring 2 is used to improve the adaptability and buffering performance of the artificial muscle; the intelligent material is used to provide the main driving force.

[0010] The variable limiter 1 is in the shape of a closed ring as a whole, and includes two end plates 11 arranged parallel to each other, and two bent rods 12 are connected between the two end plates 11, and the cross-sectional size of the bent rod 12 is smaller than the cross-sectional size of the end plate 11, and the middle part of the bent rod 12 is bent toward the inner side of the ring, and the bending angle thereof is adjusted according to the force applied to the end plate 11;

[0011] Preferably, the angle of the bend on the bent rod 12 is 150-170 degrees.

[0012] The rigid-flexible coupling ring 2 is elliptical in shape as a whole, and the ellipse is formed by connecting two straight line segments and two semicircular arc segments.

[0013] Among them, the middle part of the straight segment is a flexible segment 21 made of flexible material, and the other parts of the rigid-flexible coupling ring 2 are rigid segments 22 made of rigid material; the rigid segment 22 provides support and maintains the shape, and the flexible segment 21 enables the artificial muscle to produce a predetermined size of deformation when subjected to external force.

[0014] The variable limiter 1 and the rigid-flexible coupling ring 2 are alternately connected to form a chain-like artificial muscle.

[0015] That is, both sides of each variable limiter 1 are connected with a rigid-flexible coupling ring 2 ; and each rigid-flexible coupling ring 2 is connected with one or two variable limiters 1 .

[0016] Among them, in the variable limiter 1, a transverse pull rope 31 made of smart material is arranged between the two curved rods 12.

[0017] The transverse pull rope 31 is arranged parallel to the end plate 11;

[0018] The transverse pull rope 31 is connected to the apex of the bending portion of the bending rod 12 .

[0019] Among them, in the variable limiter 1, a longitudinal pull rope 32 made of smart material is arranged between the two rigid-flexible coupling rings 2.

[0020] The longitudinal pull rope 32 is substantially perpendicular to the end plate 11;

[0021] The longitudinal pull rope 32 is connected to the top of the rigid-flexible coupling ring 2 .

[0022] Wherein, the smart material is a liquid crystal elastomer; the liquid crystal elastomer can achieve axial contraction by converting anisotropy to isotropy under light or thermal stimulation.

[0023] Each transverse pull rope 31 and each longitudinal pull rope 32 is coated with a protective layer to block light or insulate temperature; a light source or a heat source is also provided inside the protective layer to adjust the contraction amount of the transverse pull rope 31 and the longitudinal pull rope 32 by controlling the light intensity of the light source or the temperature of the heat source;

[0024] Preferably, the light sources / heat sources in each protective layer are controlled independently of each other, and the light intensity / temperature in each protective layer may be different.

[0025] Wherein, on the variable limiter 1, a groove 4 is opened on the inner side of the end plate 11, and the rigid-flexible coupling ring 2 is embedded in the groove 4;

[0026] Preferably, one or more rigid-flexible coupling rings 2 are buckled between two adjacent variable limiters 1;

[0027] When the number of the rigid-flexible coupling rings 2 between two adjacent variable limiters 1 is more than two, correspondingly, more than two grooves 4 are also provided on each end plate 11;

[0028] The end of each rigid-flexible coupling ring 2 is correspondingly connected with a longitudinal pull rope 32 .

[0029] The present invention also provides a control method for an artificial muscle device with multiple contraction modes, the method comprising the following steps:

[0030] Step 1, alternately connect the variable limiter 1 and the rigid-flexible coupling ring 2 to form a chain-shaped artificial muscle, and arrange a transverse pull rope 31 and a longitudinal pull rope 32 in the variable limiter 1;

[0031] Step 2, fixing a plurality of artificial muscles on both sides of the simulated joint or simulated bone;

[0032] Step 3, by controlling the light intensity of the light source or the temperature of the heat source to adjust the contraction amount of each transverse pull rope 31 and each longitudinal pull rope 32, and then control the length of the variable limiter 1 and the rigid-flexible coupling ring 2 to simulate various muscle movement modes.

[0033] The beneficial effects of the present invention include:

[0034] (1) The artificial muscle device with multiple contraction modes provided by the present invention can simulate the three main contraction forms of muscles, so that the artificial muscle can exhibit bionic dynamic characteristics under different conditions, that is, it has multi-modal bionic capabilities;

[0035] (2) The artificial muscle device with multiple contraction modes provided by the present invention is suitable for bionic systems such as bionic robots and smart wearable devices that require precise control and stable output, and can effectively improve the flexibility and simulation effect of the device;

[0036] (3) According to the artificial muscle device with multiple contraction modes provided by the present invention, a plurality of variable limiters are arranged thereon, and the variable limiters are structures with a function similar to a negative Poisson's ratio, which can maintain stability and withstand external forces in different movement modes;

[0037] (4) According to the artificial muscle device with multiple contraction modes provided by the present invention, a plurality of rigid-flexible coupling rings are arranged on the device, wherein the rigid segments in the rigid-flexible coupling rings can provide basic support and shape retention capabilities, and the flexible segments therein allow the artificial muscle to produce appropriate deformation when subjected to external forces, thereby improving the adaptability and buffering performance of the structure;

[0038] (5) According to the artificial muscle device with multiple contraction modes provided by the present invention, a transverse pull rope and a longitudinal pull rope are arranged in the variable limiter, which can shorten the distance between each link under light or heat stimulation, thereby realizing the centripetal contraction of the overall structure; in the concentric contraction and isometric contraction modes, it acts as a driving force to drive the structure to move, thereby ensuring the force output and movement accuracy of the structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 A schematic diagram showing the overall structure of an artificial muscle device with multiple contraction modes in the present application;

[0040] Figure 2 A schematic diagram showing the structure of a variable limiter of an artificial muscle device with multiple contraction modes in the present application;

[0041] Figure 3A schematic diagram of simulating the motion states of the biceps group and the triceps group in an embodiment of the present application is shown.

[0042] Description of Reference Numerals

[0043] 1-Variable limiter

[0044] 11-End plate

[0045] 12-Bend Rod

[0046] 2-Rigid-Flexible Coupling Ring

[0047] 21-Flexible segment

[0048] 22- Rigid segment

[0049] 31-Horizontal draw cord

[0050] 32-Vertical draw cord

[0051] 4-Grooves

[0052] 5-Biceps Group

[0053] 6-Triceps Group

[0054] 7- Arm DETAILED DESCRIPTION

[0055] The present invention will be further described in detail below through the accompanying drawings and embodiments. Through these descriptions, the characteristics and advantages of the present invention will become more clear and distinct.

[0056] The word "exemplary" is used exclusively herein to mean "serving as an example, embodiment, or illustration." Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. Although various aspects of the embodiments are shown in the drawings, the drawings are not necessarily drawn to scale unless otherwise noted.

[0057] The present invention provides an artificial muscle device with multiple contraction modes, such as Figure 1 As shown in , the artificial muscle includes a variable limiter 1, a rigid-flexible coupling ring 2 and an intelligent material; the variable limiter 1 is used to maintain stability and withstand external forces in different motion modes; the rigid-flexible coupling ring 2 is used to improve the adaptability and buffering performance of the artificial muscle; and the intelligent material is used to provide the main driving force.

[0058] In a preferred embodiment, the variable limiter 1 is in the shape of a closed ring as a whole, and is a structure having a function similar to a negative Poisson's ratio, and includes two end plates 11 arranged parallel to each other, and two bent rods 12 are connected between the two end plates 11, and the cross-sectional dimensions of the bent rods 12 are smaller than the cross-sectional dimensions of the end plates 11, and the middle portion of the bent rods 12 is bent toward the inner side of the ring, and the bending angle thereof is deformed and adjusted according to the magnitude of the force applied to the end plates 11;

[0059] Preferably, the angle of the bend on the bending rod 12 is 150-170 degrees. When there is no bend, the angle of the bend is 180 degrees.

[0060] Preferably, the end plate 11 and the bent rod 12 of the variable limiter 1 are made of acrylonitrile-butadiene-staffen copolymer (ABS), and the cross-sectional size of the bent rod is 8-12 mm. 2 , preferably 10mm 2 about.

[0061] In a preferred embodiment, Figure 2 As shown in , the rigid-flexible coupling ring 2 is elliptical in shape as a whole, and the ellipse is formed by connecting two straight line segments and two semicircular arc segments.

[0062] Among them, the middle part of the straight segment is a flexible segment 21 made of flexible material, and the other parts of the rigid-flexible coupling ring 2 are rigid segments 22 made of rigid material; the rigid segment 22 provides support and maintains the shape, and the flexible segment 21 enables the artificial muscle to produce a predetermined size of deformation when subjected to external force, thereby improving the adaptability and buffering performance of the artificial muscle.

[0063] In the present application, the flexible segment is made of rubber material, has a length of 4-5 mm, and can provide a deformation amount of 50%;

[0064] The rigid section is made of ABS, with a length of about 8mm and a cross-sectional size of 15mm. 2 .

[0065] In a preferred embodiment, Figure 1 As shown in , the variable limiter 1 and the rigid-flexible coupling ring 2 are alternately connected to form a chain-like artificial muscle.

[0066] That is, both sides of each variable limiter 1 are connected with a rigid-flexible coupling ring 2 ; and each rigid-flexible coupling ring 2 is connected with one or two variable limiters 1 .

[0067] In the present application, when the artificial muscle is not under stress, there is no direct contact between the variable limiter 1 and the rigid-flexible coupling ring 2, and a certain distance is left between them. When the artificial muscle contracts centripetally, under the action of the pull rope, the distance between the variable limiter 1 and the rigid-flexible coupling ring 2 gradually decreases until they are in abutment contact.

[0068] Preferably, if Figure 1 and Figure 2 As shown in FIG. 1 , in the variable limiter 1 , a transverse pull rope 31 made of a smart material is arranged between two bent rods 12 .

[0069] The transverse pull rope 31 is arranged parallel to the end plate 11;

[0070] The transverse pull rope 31 is connected to the apex of the bending portion of the bending rod 12 .

[0071] The bent rod 12 is pulled inwardly by the transverse pull rope 31, so that the overall length of the variable limiter 1 is shortened, thereby achieving muscle contraction.

[0072] Preferably, if Figure 1 and Figure 2 As shown in FIG. 1 , in the variable limiter 1 , a longitudinal pull rope 32 made of smart material is arranged between two rigid-flexible coupling rings 2 .

[0073] The longitudinal pull rope 32 is substantially perpendicular to the end plate 11;

[0074] The longitudinal pull rope 32 is connected to the top of the rigid-flexible coupling ring 2 .

[0075] The two rigid-flexible coupling rings 2 are stretched inward by the longitudinal pull rope 32 , so that the distance between the two rigid-flexible coupling rings 2 is shortened, thereby achieving muscle contraction.

[0076] In the present application, under the joint action of the transverse pull rope 31 and the longitudinal pull rope 32, the distance between the variable limiter 1 and the two rigid-flexible coupling rings 2 is synchronously reduced, so that the entire artificial muscle can be contracted. In the concentric contraction and isometric contraction modes, the transverse pull rope 31 and the longitudinal pull rope 32 act as driving forces to drive the artificial muscle to move, ensuring the power output and movement accuracy of the artificial muscle.

[0077] In the present application, when the transverse pull rope 31 and the longitudinal pull rope 32 are controlled to contract, the overall length of the variable limiter 1 is gradually shortened, and after the rigid-flexible coupling ring 2 is embedded in the groove 4, the variable limiter 1 gradually abuts against the rigid-flexible coupling ring 2.

[0078] In a preferred embodiment, the smart material is liquid crystal elastomer (LCEs); the liquid crystal elastomer can achieve axial contraction by converting anisotropy to isotropy under light or thermal stimulation.

[0079] In a preferred embodiment, each transverse drawstring 31 and each longitudinal drawstring 32 is coated with a protective layer to provide light shielding or temperature insulation; a light source or a heat source is also provided inside the protective layer to adjust the contraction amount of the transverse drawstring 31 and the longitudinal drawstring 32 by controlling the light intensity of the light source or the temperature of the heat source;

[0080] Preferably, the light sources / heat sources in each protective layer are controlled independently of each other, and the light intensity / temperature in each protective layer can be different. Each light source / heat source is connected to a control system, and the control system sets the contraction amount for each pull rope according to the contraction force and contraction amount required by the artificial muscle, and then sets the appropriate light intensity / temperature.

[0081] In a preferred embodiment, on the variable limiter 1, a groove 4 is provided on the inner side of the end plate 11, and the rigid-flexible coupling ring 2 can be embedded in the groove 4;

[0082] Preferably, if Figure 2 As shown in , one or more rigid-flexible coupling rings 2 are commonly connected between two adjacent variable limiters 1;

[0083] When the number of the rigid-flexible coupling rings 2 between two adjacent variable limiters 1 is more than two, correspondingly, more than two grooves 4 are also provided on each end plate 11;

[0084] The end of each rigid-flexible coupling ring 2 is correspondingly connected with a longitudinal pull rope 32 .

[0085] In the present application, by providing a plurality of parallel rigid-flexible coupling rings and longitudinal pull ropes 32 connected thereto, the output force can be enhanced so that the artificial muscle remains stable and reliable under high load.

[0086] The present invention also provides a control method for an artificial muscle device with multiple contraction modes, the method comprising the following steps:

[0087] Step 1, alternately connect the variable limiter 1 and the rigid-flexible coupling ring 2 to form a chain-shaped artificial muscle, and arrange a transverse pull rope 31 and a longitudinal pull rope 32 in the variable limiter 1; the transverse pull rope 31 is connected to the apex of the bending part of the two bending rods 12 of the variable limiter; the longitudinal pull rope 32 is connected to the top of two adjacent rigid-flexible coupling rings 2;

[0088] Step 2, fixing a plurality of artificial muscles on both sides of the simulated joint or simulated bone; making the plurality of artificial muscles in an isometric contraction state, making the simulated joint or simulated bone in an extended state;

[0089] Step 3, by controlling the light intensity of the light source or the temperature of the heat source to adjust the contraction amount of each transverse pull rope 31 and each longitudinal pull rope 32, and then controlling the length of the variable limiter 1 and the rigid-flexible coupling ring 2 to simulate various muscle movement modes; the various movement modes include concentric contraction, isometric contraction and eccentric contraction.

[0090] Example

[0091] Choose Figure 1 and Figure 2 The artificial muscle device with multiple contraction modes shown in the figure simulates the biceps group and the triceps group, and specifically includes the following steps:

[0092] Step 1, alternately buckle and connect the variable limiter 1 and the rigid-flexible coupling ring 2 to form a chain-shaped artificial muscle, and arrange a transverse pull rope 31 and a longitudinal pull rope 32 in the variable limiter 1;

[0093] Step 2, forming two artificial muscles, respectively simulating the biceps group 5 and the triceps group 6, and connecting the biceps group 5 and the triceps group 6 to the two sides of the simulated elbow joint, respectively. In the initial state of the system, the biceps and the triceps are both in an isometric contraction state, and the arm 7 is kept straight;

[0094] Step 3, simulate arm flexion: Figure 3 As shown in B, at the beginning of arm flexion, light stimulation is applied to the smart material in the biceps group to cause it to contract concentrically, generate contraction force and drive the arm to bend; at the same time, in order to control the speed and stability of arm flexion, the light stimulation of the smart material in the triceps group is controlled to apply a gradually stretching external force to make it enter the eccentric contraction mode; at this time, the variable limiter of the triceps group bears part of the external force through the negative Poisson's ratio structure, that is, when the variable limiter is in contact with the rigid-flexible coupling ring, part of the force can be directly transmitted between the variable limiter and the rigid-flexible coupling ring, reducing the load-bearing burden of the smart material, so as to prevent the artificial muscle from being damaged by external force, and at the same time achieve smooth braking; by adjusting the concentric contraction force of the biceps group and the eccentric contraction resistance of the triceps group, the flexion angle and speed of the arm can be accurately controlled.

[0095] Simulate arm extension: Figure 3 As shown in C, during the arm extension process, light stimulation is applied to the smart material in the triceps group to cause it to produce concentric contraction, thereby driving the arm to extend; at this time, the light stimulation of the smart material in the biceps group is controlled to apply a gradual stretching external force to cause it to enter a centrifugal contraction mode, thereby avoiding arm instability caused by rapid extension; at the same time, the variable limiter absorbs external force with the support of the negative Poisson's ratio structure, disperses stress and protects the smart material; by precisely controlling the concentric contraction of the triceps group and the centrifugal resistance of the biceps group, the arm remains stable during the extension process, thereby avoiding movement imbalance caused by sudden pulling force.

[0096] Simulate arm isometric mode: Figure 3 As shown in A, when the arm is kept motionless at a specific angle, the contraction strength of the biceps and triceps is controlled by precisely controlling the intensity of light applied by the smart materials in the two groups of biceps and triceps, so that both are in isometric contraction mode; at this time, the two groups of muscles maintain a consistent length, and thus work together to stabilize the arm posture, that is, the two sides are the same length, which is the isometric mode, but have enough force to resist external force disturbances.

[0097] The multiple contraction modes of the artificial muscle with multiple contraction modes can achieve coordinated movements similar to those of the biceps and triceps on the bionic arm, accurately control the flexion and extension of the arm, and simulate the flexibility and precise control of biological joints. This configuration not only effectively improves the motion stability of the flexible bionic robot, but also ensures the durability of the artificial muscle under external forces through the eccentric contraction mode, meeting the requirements of bionic robots or smart wearable devices for flexibility and mechanical stability.

[0098] The present invention has been described above in conjunction with preferred embodiments, but these embodiments are only exemplary and serve only as an illustration. On this basis, the present invention may be subjected to a variety of substitutions and improvements, all of which fall within the scope of protection of the present invention.

Claims

1. An artificial muscle device with multiple contraction modes, characterized in that: The artificial muscle comprises a variable stopper (1), a rigid-flexible coupling ring (2) and an intelligent material; the variable stopper (1) is used to maintain stability and withstand external forces in different motion modes; the rigid-flexible coupling ring (2) is used to improve the adaptability and buffering performance of the artificial muscle; and the intelligent material is used to provide a main driving force.

2. The artificial muscle device with multiple contraction modes according to claim 1, characterized in that: The variable limiter (1) is in the shape of a closed ring as a whole, and comprises two end plates (11) arranged parallel to each other, two bent rods (12) are connected between the two end plates (11), the cross-sectional dimensions of the bent rods (12) are smaller than the cross-sectional dimensions of the end plates (11), and the middle portion of the bent rods (12) is bent toward the inner side of the ring, and the bending angle thereof is adjusted according to the magnitude of the force applied to the end plates (11); Preferably, the angle of the bend on the bent rod (12) is 150-170 degrees.

3. The artificial muscle device with multiple contraction modes according to claim 1, characterized in that: The rigid-flexible coupling ring (2) is elliptical in shape as a whole, and the ellipse is formed by connecting two straight line segments and two semicircular arc segments. The middle part of the straight line segment is a flexible segment (21) made of a flexible material, and the other parts of the rigid-flexible coupling ring (2) are rigid segments (22) made of a rigid material; the rigid segment (22) provides support and maintains the shape, and the flexible segment (21) enables the artificial muscle to generate a predetermined deformation when subjected to an external force.

4. The artificial muscle device with multiple contraction modes according to claim 2, characterized in that: The variable stopper (1) and the rigid-flexible coupling ring (2) are alternately connected to form a chain-shaped artificial muscle. That is, both sides of each variable stopper (1) are connected to rigid-flexible coupling rings (2); and each rigid-flexible coupling ring (2) is connected to one or two variable stoppers (1).

5. The artificial muscle device with multiple contraction modes according to claim 2, characterized in that: In the variable limiter (1), a transverse pull rope (31) made of smart material is arranged between two curved rods (12). The transverse pull rope (31) is arranged in parallel with the end plate (11); The transverse pull rope (31) is connected to the apex of the bent portion of the bent rod (12).

6. The artificial muscle device with multiple contraction modes according to claim 5, characterized in that: In the variable limiter (1), a longitudinal pull rope (32) made of smart material is arranged between two rigid-flexible coupling rings (2). The longitudinal draw cord (32) is substantially perpendicular to the end plate (11); The longitudinal pull rope (32) is connected to the top end of the rigid-flexible coupling ring (2).

7. The artificial muscle device with multiple contraction modes according to claim 6, characterized in that: The smart material is a liquid crystal elastomer; the liquid crystal elastomer can achieve axial contraction by converting anisotropy to isotropy under light or thermal stimulation.

8. The artificial muscle device with multiple contraction modes according to claim 7, characterized in that: Each transverse pull rope (31) and each longitudinal pull rope (32) is coated with a protective layer to provide light shielding or heat insulation; a light source or a heat source is also provided inside the protective layer to adjust the contraction amount of the transverse pull rope (31) and the longitudinal pull rope (32) by controlling the light intensity of the light source or the temperature of the heat source; Preferably, the light sources / heat sources in each protective layer are controlled independently of each other, and the light intensity / temperature in each protective layer may be different.

9. The artificial muscle device with multiple contraction modes according to claim 4, characterized in that: On the variable stopper (1), a groove (4) is provided on the inner side of the end plate (11), and the rigid-flexible coupling ring (2) can be embedded in the groove (4) when it is contracted; Preferably, one or more rigid-flexible coupling rings (2) are buckled between two adjacent variable limiters (1); When the number of the rigid-flexible coupling rings (2) between two adjacent variable limiters (1) is more than two, correspondingly, more than two grooves (4) are also provided on each end plate (11); The end of each rigid-flexible coupling ring (2) is correspondingly connected to a longitudinal pull rope (32).

10. A control method for an artificial muscle device having multiple contraction modes, characterized in that: The method comprises the following steps: Step 1, alternately connecting a variable stopper (1) and a rigid-flexible coupling ring (2) to form a chain-shaped artificial muscle, and arranging a transverse pull rope (31) and a longitudinal pull rope (32) in the variable stopper (1); Step 2, fixing a plurality of artificial muscles on both sides of the simulated joint or simulated bone; Step 3, by controlling the light intensity of the light source or the temperature of the heat source to adjust the contraction amount of each transverse pull rope (31) and each longitudinal pull rope (32), and then control the length of the variable limiter (1) and the rigid-flexible coupling ring (2), simulating various muscle movement modes.

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