Artificial Muscle Based on Hydraulic Amplification and Self-Repairing Electrostatic Drive

Abstract

The present invention discloses an artificial muscle based on hydraulic amplification self-repair electrostatic drive, which includes a drive module and a connection unit module; in the connection unit module, the top cover and the bottom cover are connected by the drive module and the support spring; a power jack is arranged on the outer circumferential surface of the bottom cover; in the drive module, both the outer elastic wrapping layer and the inner elastic wrapping layer are tubular structures, and a liquid dielectric is uniformly filled between the outer elastic wrapping layer and the inner elastic wrapping layer; compliant electrodes are arranged on the outer surface of the outer elastic wrapping layer and the inner surface of the inner elastic wrapping layer, and outer constraint fibers are uniformly arranged on the outer surface of the outer compliant electrode, and the circumferential positions of the outer compliant electrode and the inner compliant electrode respectively correspond to the positions of the power sockets on the circumferential surface of the bottom cover; the number of the inner compliant electrodes is the same as that of the outer compliant electrodes; the design of the regional distribution of the electrode layer and the voltage control drive mode enable the high-performance artificial muscle based on force-electricity-hydraulic coupling drive proposed by the present invention to achieve multi-mode deformation and precise and controllable deformation.

Description

Technical Field

[0001] The present invention belongs to the technical field of soft actuators and soft robots, and relates to an artificial muscle based on hydraulic amplification self-healing electrostatic drive. Background Art

[0002] As a new type of drive technology, soft drive has been widely studied and applied in the fields of intelligent bionic drive, soft robots, controllable optics, energy capture, etc. due to its advantages such as softness and variability, safe and reliable human-computer interaction, and strong adaptability to unstructured environments. The actuators based on this drive technology are usually called artificial muscles.

[0003] The artificial muscles in the prior art can be mainly divided into thermal drive type, pneumatic drive type and electric drive type. Among them, the thermal drive type uses the phase change of materials to generate deformation (such as shape memory polymers), and the pneumatic drive type uses inflation or deflation to make the elastic cavity expand or contract to realize the movement of the muscle. These two types of artificial muscles have low response rates, low sensitivity and complex structures, so their applications are very limited. The electric drive type uses electrostatic action to achieve drive deformation, so it has a fast response and is easy to control. The typical representative is dielectric elastomer drive.

[0004] However, dielectric elastomers are prone to electrical breakdown failure when excited by voltage, which makes it difficult for dielectric elastomer drive technology to be widely applied. Although the hydraulic amplification self-healing electrostatic (HASEL) technology can effectively solve the above problems, the existing HASEL-based artificial muscles lack load-bearing capacity and integration, and have a single deformation mode. Summary of the Invention

[0005] The purpose of the present invention is to solve the above problems in the prior art, and provide a design method for an artificial muscle based on hydraulic amplification self-healing electrostatic drive. By drawing on the characteristics of the tubular drive structure and integrating the principle of hydraulic amplification self-healing electrostatic drive, this method proposes a design method for a self-healing artificial muscle with high performance, easy integration, strong load-bearing capacity and diversified deformation modes; thus providing a solid theoretical basis and practical experience for the design of soft actuators and their applications in soft robots.

[0006] To achieve the above object, the present invention provides an artificial muscle based on hydraulic amplification self-repair electrostatic drive, including a drive module and a connection unit module; the connection unit module includes a top cover and a bottom cover arranged concentrically, the top cover and the bottom cover are connected by the drive module and a support spring, and in the initial state of the artificial muscle, the support spring is in a compressed state against the gravity of the top cover; a power jack is provided on the outer circumferential surface of the bottom cover; a locking mechanism is provided on the top cover, and a joint for connecting the locking mechanism is provided on the bottom surface of the bottom cover; the drive module includes an outer constraint fiber, an outer compliant electrode, an outer elastic wrapping layer, a liquid dielectric, an inner elastic wrapping layer, an inner compliant electrode, and an inner constraint fiber; wherein both the outer elastic wrapping layer and the inner elastic wrapping layer are tubular structures, and a liquid dielectric is uniformly filled between the outer elastic wrapping layer and the inner elastic wrapping layer; outer compliant electrodes are uniformly arranged on the outer surface of the outer elastic wrapping layer, outer constraint fibers are uniformly arranged on the surface of the outer compliant electrodes, inner compliant electrodes are uniformly arranged on the inner surface of the inner elastic wrapping layer, and the circumferential positions of the outer compliant electrodes and the inner compliant electrodes respectively correspond to the positions of the power sockets on the circumferential surface of the bottom cover; the number of the inner compliant electrodes is the same as that of the outer compliant electrodes and they correspond one by one; the power jack is connected to the inner compliant electrode and the outer compliant electrode through a wire.

[0007] Both the outer compliant electrode and the inner compliant electrode are coating layers, and a set gap is left between adjacent electrodes.

[0008] When only requiring the artificial muscle based on hydraulic amplification self-repair electrostatic drive to perform only telescopic motion, the number of electrode groups of the inner compliant electrode and the outer compliant electrode is not less than one group. If requiring the artificial muscle based on hydraulic amplification self-repair electrostatic drive to perform bending motion, the number of electrode groups of the inner compliant electrode and the outer compliant electrode is greater than one group.

[0009] When the number of groups of the inner compliant electrode and the outer compliant electrode is greater than one group, the positions of the inner compliant electrode and the outer compliant electrode are symmetrically distributed about the axis of the tubular structure.

[0010] The number of the inner compliant electrode and the outer compliant electrode is set in direct proportion to the requirement of deformation accuracy.

[0011] A groove is provided on the top cover, and the locking structure is arranged in the groove. The locking structure includes two locking push rods, four locking link rods, two locking springs and two locking sliders. One end of each locking push rod is connected to one end of the two locking link rods by a hinge. A locking spring is arranged between the two locking link rods connected to the same locking push rod, and both ends of the locking spring are fixed on the two locking link rods respectively. Both ends of each locking slider are hinged to the other ends of the two locking link rods respectively; the locking spring always remains in a stretched state, and the other end of the locking push rod is the pressing end; one side of the two locking sliders forms a V-shaped opening, and the other side is the locking plane; the joint is connected to the bottom cover through a connecting column, the cross-section of the connecting column is smaller than that of the joint, the joint is block-shaped, the outer end face is arc-shaped or V-shaped, and the other end face is the locking face.

[0012] The drive modules are connected in series through the connection module.

[0013] A parallel platform is provided, and multiple connection modules are arranged on the parallel platform. The multiple drive modules are connected in parallel through the connection module.

[0014] The drive modules are connected in series through the connection module to form a series structure, and the series structure is then connected in parallel through the parallel platform to form a series-parallel hybrid structure.

[0015] Compared with the prior art, the present invention has at least the following beneficial effects:

[0016] Based on the high-performance artificial muscle driven by force-electricity-hydraulic coupling, by designing the elastic wrapping layer of the tubular structure and setting the support spring between the top cover and the bottom cover, the present invention has higher load-bearing capacity; through the connection unit module, the end of the high-performance artificial muscle driven by force-electricity-hydraulic coupling is ingeniously designed, and the series and parallel connection modes of the present invention can be realized, making it have the characteristics of high integration; through the drive module, the design of the electrode layer area distribution and the voltage control drive mode enable the high-performance artificial muscle driven by force-electricity-hydraulic coupling proposed by the present invention to realize multi-mode deformation and precise controllable deformation; the high-performance artificial muscle driven by force-electricity-hydraulic coupling of the present invention well overcomes the shortcomings existing in the prior art, has a simple manufacturing process, low cost, simple and controllable drive, fast response speed, small mass and high energy density. Description of the Drawings

[0017] Figure 1 is the three-dimensional assembly schematic diagram of the artificial muscle based on hydraulic amplification self-healing electrostatic drive;

[0018] Figure 2 is the front view of the artificial muscle based on hydraulic amplification self-healing electrostatic drive;

[0019] Figure 3 is Figure 2A cross-sectional view of only the driving module of the artificial muscle based on hydraulic amplification self-repair electrostatic drive, longitudinally sectioned;

[0020] Figure 4 is Figure 3 a partially enlarged view;

[0021] Figure 5 is Figure 4 the left view of;

[0022] Figure 6 Schematic diagrams of the two half-section structures and the locking structure of the top cover of the artificial muscle based on hydraulic amplification self-repair electrostatic drive;

[0023] Figure 7 Schematic diagram of the series-parallel connection part of the artificial muscle based on hydraulic amplification self-repair electrostatic drive;

[0024] Figure 8 Schematic diagram of the bending after applying voltage to the artificial muscle based on hydraulic amplification self-repair electrostatic drive;

[0025] Figure 9 Partial examples of the series and parallel connections of the artificial muscle based on hydraulic amplification self-repair electrostatic drive;

[0026] Description of reference numerals

[0027] 1 - top cover, 21 - outer constraint fiber, 22 - outer compliant electrode, 23 - outer elastic wrapping layer, 24 - liquid dielectric, 25 - inner elastic wrapping layer, 26 - inner compliant electrode, 27 - inner constraint fiber, 3 - bottom cover, 4 - bottom cover without power jack, 5 - parallel platform, 6 - support spring, 11 - locking structure, 111 - locking push rod, 112 - locking connecting rod, 113 - locking spring, 114 - locking slider. Detailed implementation manners

[0028] The following further describes the present invention in detail with reference to the drawings and embodiments:

[0029] In order to make the technical means, creative features, achieved purposes and effects of the present invention easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. It should be noted that the same or identically functioning components in the drawings of the present invention will use the same reference numerals; at the same time, in order to better display the internal structure, some unimportant components will be omitted.

[0030] As Figures 1 - 7As shown in the figure, the artificial muscle based on hydraulic amplification self-repair electrostatic drive proposed in this application includes a drive module, a connection unit module, and a support spring 6; the connection unit module includes a top cover 1, a locking structure 11 arranged in the groove of the top cover 1, and a bottom cover 3 coaxial with the top cover. The top cover 1 and the bottom cover 3 are connected by the drive module and the support spring 6; four groups of power jacks are evenly arranged on the outer circumferential surface of the bottom cover 3.

[0031] Among them, referring to Figure 2 , Figure 3 , Figure 4 , Figure 5 , the drive module is the main part of the artificial muscle based on hydraulic amplification self-repair electrostatic drive. Drawing on the driving characteristics of the tubular structure, the drive module includes an outer constraint fiber 21, an outer compliant electrode 22, an outer elastic wrapping layer 23, a liquid dielectric 24, an inner elastic wrapping layer 25, an inner compliant electrode 26, and an inner constraint fiber 27. Among them, both the outer elastic wrapping layer 23 and the inner elastic wrapping layer 25 are tubular structures, and a liquid dielectric 24 is evenly filled between the outer elastic wrapping layer 23 and the inner elastic wrapping layer 25; four groups of outer compliant electrodes 22 are evenly arranged on the outer surface of the outer elastic wrapping layer 23, and the circumferential positions of the outer compliant electrodes 22 correspond to the positions of the four groups of power sockets on the circumferential surface of the bottom cover 3 respectively. Nine groups of outer constraint fibers 21 are evenly arranged on the surface of the outer compliant electrode 22. Four groups of inner compliant electrodes 26 are evenly arranged on the inner surface of the inner elastic wrapping layer 25, and the circumferential positions of the inner compliant electrodes 26 correspond to the positions of the four groups of power sockets on the circumferential surface of the bottom cover 3 respectively. Each group of inner compliant electrodes 26 corresponds to an outer compliant electrode 22 one by one. Nine groups of inner constraint fibers 27 are evenly arranged on the inner surface of the inner compliant electrode 26. It should be noted that both the outer compliant electrode 22 and the inner compliant electrode 26 are coating layers, and a certain gap is left between adjacent electrodes to ensure the independent control of each group of electrodes. It should also be noted that setting four groups of inner compliant electrodes 26 and outer compliant electrodes 22 is only one specific implementation case of the artificial muscle based on hydraulic amplification self-repair electrostatic drive proposed in this application. When applying the artificial muscle based on hydraulic amplification self-repair electrostatic drive, the number of inner compliant electrodes 26 and outer compliant electrodes 22 can be appropriately increased or decreased according to the actual deformation accuracy requirements. When only requiring the artificial muscle based on hydraulic amplification self-repair electrostatic drive to perform telescopic movement, the number of electrode groups of the inner compliant electrodes 26 and the outer compliant electrodes 22 is not less than one group. However, when requiring the artificial muscle based on hydraulic amplification self-repair electrostatic drive to perform bending movement, the number of electrode groups of the inner compliant electrodes 26 and the outer compliant electrodes 22 must be greater than one group.

[0032] Furthermore, the inner constraint fibers 27 and the outer constraint fibers 21 can play a good role in constraining the liquid dielectric 24, enabling the liquid dielectric 24 to be evenly distributed between the inner elastic wrapping layer 25 and the outer elastic wrapping layer 23, avoiding bulging during the deformation process of the present invention, making it possible for us to control the deformation of the present invention more precisely and making its deformation direction more accurate. At the same time, it should also be pointed out that setting nine groups of inner constraint fibers 27 and outer constraint fibers 21 is only one specific implementation case of the artificial muscle based on hydraulic amplification self-healing electrostatic drive proposed in this application. When applying the artificial muscle based on hydraulic amplification self-healing electrostatic drive, the number of inner compliant electrodes 26 and outer compliant electrodes 22 can be appropriately increased or decreased according to the actual deformation accuracy requirements. The number of inner compliant electrodes 26 and outer compliant electrodes 22 should at least ensure that the liquid dielectric is evenly distributed when the artificial muscle based on hydraulic amplification self-healing electrostatic drive is in the original vertical state. The longer the initial vertical length of the tubular structure set, correspondingly, the number of inner compliant electrodes 26 and outer compliant electrodes 22 should also increase accordingly.

[0033] Furthermore, by applying voltages with opposite polarities to the inner compliant electrode 26 and the outer compliant electrode 22, due to the generation of Maxwell stress between the inner compliant electrode 26 and the outer compliant electrode 22, the area covered between each group of inner compliant electrode 26 and outer compliant electrode 22 undergoes deformation. By changing the direction, magnitude, and frequency of the applied voltage, precise control of the deformation of the present invention can be achieved.

[0034] Furthermore, by setting the dielectric between the inner elastic wrapping layer 25 and the outer elastic wrapping layer 23 as the liquid dielectric 24, the flowable liquid dielectric enables the artificial muscle proposed in the present invention to have a self-healing function when suffering from dielectric breakdown damage, thereby prolonging the service life of the artificial muscle.

[0035] As Figure 8 shown, this schematic diagram shows a situation of the bending deformation of the artificial muscle based on hydraulic amplification self-healing electrostatic drive proposed in the present invention.

[0036] As Figure 2 、 Figure 5 、 Figure 6 a、 Figure 6 b、 Figure 6 c、 Figure 6 d、 Figure 7As shown in the figure, the connection unit module includes a top cover 1, a locking structure 11 arranged in the groove of the top cover 1, and a bottom cover 3 coaxial with the top cover. The top cover 1 and the bottom cover 3 are connected by a driving module and a support spring 6. In the initial state of the artificial muscle based on hydraulic amplification self-repair electrostatic drive, the support spring 6 is in a compressed state against the gravity of the top cover 1. The support spring 6 is used to connect the top cover 1 and the bottom cover 3, and secondly, it plays a role in supporting the main body during the stretching or bending process of the artificial muscle based on hydraulic amplification self-repair electrostatic drive. Four groups of power jacks are evenly arranged on the outer circumferential surface of the bottom cover 3. The four groups of power jacks are connected to each group of inner compliant electrodes 26 and outer compliant electrodes 22 through wires. The number of power jacks corresponds one by one to the number of each group of inner compliant electrodes 26 and outer compliant electrodes 22. A positioning boss is arranged on the lower surface of the bottom cover 3, aiming at its connection and disconnection with the locking structure 11, providing a structural basis for the series and parallel connection of the artificial muscle based on hydraulic amplification self-repair electrostatic drive. A locking structure 11 includes two locking push rods 111, four locking link rods 112, two locking springs 113 and two locking sliders 114. One end of each locking push rod 111 is connected to one end of two locking link rods 112 in an articulated manner. A locking spring 113 is arranged between the two locking link rods 112 connected to the same locking push rod 111. The two ends of the locking spring 113 are respectively fixed on the two locking link rods 112. The two ends of each locking slider 114 are respectively articulated with the other ends of the two locking link rods 112. The locking spring 113 always remains in a stretched state, so the included angle between the two locking link rods 112 connected to the locking spring 113 is the smallest. The two locking sliders 114 respectively connected to the two locking link rods 112 connected to the locking spring 113 are initially in a closed state. By pressing the locking push rod 111, overcoming the pulling force of the locking spring 113 on the locking link rod 112 connected to it, the included angle between the two locking link rods 112 connected to the locking spring 113 gradually becomes larger. When the included angle between them becomes the largest, the two locking sliders 114 respectively connected to the two locking link rods 112 will be in an open state. At this time, the arc-shaped boss of the bottom cover 3 of another artificial muscle based on hydraulic amplification self-repair electrostatic drive connected in parallel or in series with this locking mechanism 11 can be taken out or inserted. Canceling the pressing of the locking push rod 111, the locking slider 114 will return to the closed state again.

[0037] Reference Figure 9 a, Figure 9 b. Based on the locking structure 11 proposed above, two connection methods of the artificial muscle based on hydraulic amplification self-repair electrostatic drive are proposed: series connection and parallel connection.

[0038] Reference Figure 9 a, Figure 9 b and Figure 9c; The series connection method can be achieved through the connection unit module, making the deformation mode of the present invention more free and variable. The parallel connection method can be achieved by setting multiple connection unit modules on the parallel platform 5, further improving the load-bearing capacity and integration of the present invention. In the illustration, we show the series and parallel connections between four artificial muscle monomers based on hydraulic amplification self-healing electrostatic drive. For the series connection method, only the arc-shaped convex heads of the top covers 3 of every two connected artificial muscle monomers based on hydraulic amplification self-healing electrostatic drive need to be connected to the top cover 1 containing the locking structure 11. For the parallel connection method, the present invention designs a parallel platform 5. In the illustrated parallel connection, four artificial muscle monomers based on hydraulic amplification self-healing electrostatic drive are distributed in a circular pattern on the parallel platform 5, and their upper and lower ends are respectively connected to the parallel platform 5. However, the difference is that four top covers 1 containing the locking structure 11 are evenly fixed on the lower parallel platform 5, which are respectively connected to the bottom covers 3 of the four artificial muscle monomers based on hydraulic amplification self-healing electrostatic drive. Four bottom covers 3 without power jacks are evenly fixed on the lower surface of the upper parallel platform 5, which are respectively connected to the top covers 1 of the four artificial muscle monomers based on hydraulic amplification self-healing electrostatic drive. It should be noted that series and parallel are only the most basic connection methods of the present invention. In the actual application of artificial muscles based on hydraulic amplification self-healing electrostatic drive, various different series and parallel combination connection methods can be adopted according to different needs.

Claims

1. An artificial muscle based on hydraulic amplification self-repair electrostatic drive, characterized in that, It includes a driving module and a connection unit module; the connection unit module includes a top cover (1) and a bottom cover (3) arranged concentrically. The top cover (1) and the bottom cover (3) are connected by the driving module and a support spring (6). In the initial state of the artificial muscle, the support spring (6) is in a compressed state against the gravity of the top cover (1); a power jack is provided on the outer circumferential surface of the bottom cover (3); a locking mechanism is provided on the top cover (1), and a joint for connecting the locking mechanism is provided on the bottom surface of the bottom cover (3); the driving module includes an outer constraint fiber (21), an outer compliant electrode (22), an outer elastic wrapping layer (23), a liquid dielectric (24), an inner elastic wrapping layer (25), an inner compliant electrode (26), and an inner constraint fiber (27); among them, both the outer elastic wrapping layer (23) and the inner elastic wrapping layer (25) are tubular structures, and a liquid dielectric (24) is uniformly filled between the outer elastic wrapping layer (23) and the inner elastic wrapping layer (25); outer compliant electrodes (22) are uniformly arranged on the outer surface of the outer elastic wrapping layer (23), outer constraint fibers (21) are uniformly arranged on the surface of the outer compliant electrodes (22), inner compliant electrodes (26) are uniformly arranged on the inner surface of the inner elastic wrapping layer (25), and the circumferential positions of the outer compliant electrodes (22) and the inner compliant electrodes (26) correspond to the positions of the power jacks on the circumferential surface of the bottom cover (3) respectively; the number of the inner compliant electrodes (26) is the same as that of the outer compliant electrodes (22) and they correspond one by one; the power jacks are connected to the inner compliant electrodes (26) and the outer compliant electrodes (22) through wires; when only requiring the artificial muscle based on hydraulic amplification self-repair electrostatic drive to perform only telescopic movement, the number of electrode groups of the inner compliant electrodes (26) and the outer compliant electrodes (22) is not less than one group. If requiring the artificial muscle based on hydraulic amplification self-repair electrostatic drive to perform bending movement, the number of electrode groups of the inner compliant electrodes (26) and the outer compliant electrodes (22) is greater than one group; when the number of groups of the inner compliant electrodes (26) and the outer compliant electrodes (22) is greater than one group, the positions of the inner compliant electrodes (26) and the outer compliant electrodes (22) are symmetrically distributed about the axis of the tubular structure; a groove is provided on the top cover (1), and the locking structure (11) is arranged in the groove. The locking structure (11) includes two locking push rods (111), four locking link rods (112), two locking springs (113), and two locking sliders (114). One end of each locking push rod (111) is connected to one end of two locking link rods (112) by a hinged manner. A locking spring (113) is arranged between the two locking link rods (112) connected to the same locking push rod (111). Both ends of the locking spring (113) are fixed on the two locking link rods (112) respectively. Each end of each locking slider (114) is hinged to the other ends of the two locking link rods (112); the locking spring (113) always remains in a stretched state, and the other end of the locking push rod (111) is a pressing end; one surface of the two locking sliders (114) forms a V-shaped opening, and the other surface is a locking plane;The joint is connected to the bottom cover (3) through a connecting column. The cross-section of the connecting column is smaller than that of the joint. The joint is block-shaped, with an outer end face being arc-shaped or V-shaped, and the other end face being a locking face.; 2. The artificial muscle based on hydraulic amplification self-repair electrostatic drive according to claim 1, wherein Both the outer compliant electrode (22) and the inner compliant electrode (26) are coating layers, and a set gap is left between adjacent electrodes.

3. The artificial muscle based on hydraulic amplification self-repairing electrostatic drive according to claim 1, characterized in that, The number of the inner compliant electrodes (26) and the outer compliant electrodes (22) is set in direct proportion to the deformation accuracy requirements.

4. The artificial muscle based on hydraulic amplification self-repair electrostatic drive according to claim 1, characterized in that, The drive modules are connected in series through the connection modules.

5. The artificial muscle based on hydraulic amplification self-repairing electrostatic drive according to claim 1, characterized in that, A parallel platform (5) is provided, and a plurality of connection modules are provided on the parallel platform (5), and a plurality of drive modules are connected in parallel through the connection modules.

6. The artificial muscle based on hydraulic amplification self-repairing electrostatic drive according to claim 5, wherein The drive modules are connected in series through the connection modules to form a series structure, and the series structure is then connected in parallel through the parallel platform (5) to form a series-parallel hybrid structure.

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