Bionic skin structure

Abstract

This application relates to a biomimetic skin structure, comprising a functional structure and a sensing structure. The sensing structure is located on one side of the functional structure and is electrically connected to it. The functional structure has electrostrictive properties; when the sensing structure generates changes in electrical signals in response to environmental changes, the functional structure deforms in response to these changes. This application electrically connects the electrostrictive functional structure with the sensing structure capable of generating changes in electrical signals, thereby simulating the skin's emergency response to environmental changes through the expansion and contraction of the functional structure.

Description

Technical Field

[0001] The present application relates to the field of bionic technology, and in particular to a bionic skin structure. Background Art

[0002] Skin covers the surface of the body and is in direct contact with the external environment. It has the functions of protection, excretion, regulating body temperature and sensing external stimuli. It is one of the important organs of the human body. Therefore, it is of great research significance and application value to imitate and prepare the various functions of skin. However, most of the current bionic skins are developed from the aspects of material modification and doping, and lack the structural design of bionic skin. Summary of the invention

[0003] In response to the above technical problems, the present application provides a bionic skin structure, which electrically connects a functional structure with electrostrictive function with a sensing structure that can generate electrical signal changes, so that the emergency response of the skin to environmental changes can be simulated through the expansion and contraction changes of the functional structure.

[0004] In order to solve the above technical problems, the present application provides a bionic skin structure, including a functional structure and a sensing structure, wherein the sensing structure is located on one side of the functional structure and is electrically connected to the functional structure, and the functional structure has an electrostrictive function. When the sensing structure generates an electrical signal change with changes in the environment, the functional structure deforms in response to the change in the electrical signal.

[0005] Optionally, the functional structure includes a central ring body and a plurality of connecting arms, wherein the plurality of connecting arms are arranged at intervals along the circumference of the central ring body, the first end of the connecting arm is connected to the central ring body, the second end of the connecting arm is fixed, and the second ends of the plurality of connecting arms are electrically connected to the sensing structure in whole or in part.

[0006] Optionally, the first ends of the multiple connecting arms are electrically connected to each other through the central ring body, and the second ends of the multiple connecting arms are electrically connected to the sensing structure.

[0007] Optionally, the sensing structure includes a plurality of sensing branches, the first ends of the plurality of sensing branches are electrically connected to each other, and the second ends of the plurality of sensing branches are electrically connected to the second ends of the plurality of connecting arms in a one-to-one correspondence.

[0008] Optionally, the first ends of the multiple sensing branches are interconnected and conductive, and the connection between the first ends of the multiple sensing branches coincides with the projection of the center point of the central ring body.

[0009] Optionally, the central ring body is divided into at least two ring segments by an insulating part, each ring segment is respectively connected to two of the connecting arms, the sensing structure includes at least two sensing parts, the ring segments and the sensing parts are alternately arranged, the second ends of the connecting arms connected to the same ring segment are respectively electrically connected to ends of different sensing parts, and the second end of a connecting arm among the multiple connecting arms is insulated from the end of the corresponding sensing part for connecting an external circuit.

[0010] Optionally, the second end of the connecting arm is fixed on the sensing structure, and / or the connecting arm is curved.

[0011] Optionally, the sensing structure is a cross structure, the central intersection point of the cross structure coincides with the projection of the central point of the central ring body, the number of the connecting arms is 4, and the second end of each connecting arm corresponds to an end of the sensing structure.

[0012] Optionally, the sensing structure includes a conductive material and a sensing material coated outside the conductive material. When the sensing material is deformed with changes in the environment, a cross-sectional size of the conductive material changes to generate a change in the electrical signal.

[0013] Optionally, the conductive material is liquid metal, conductive polymer or conductive hydrogel, and the sensing material is elastic insulating material, temperature-controlled shape memory polymer or hydrogel material.

[0014] The bionic skin structure of the present application includes a functional structure and a sensing structure. The sensing structure is located on one side of the functional structure and is electrically connected to the functional structure. The functional structure has an electrostrictive function. When the sensing structure generates an electrical signal change as the environment changes, the functional structure deforms in response to the change in the electrical signal. The present application electrically connects the functional structure with the electrostrictive function with the sensing structure that can generate an electrical signal change. When the sensing structure generates an electrical signal change as the environment changes, the emergency response of the skin to the environmental change can be simulated by the expansion and contraction change of the functional structure. In addition, through the sensing between the mechanical structures, the simulation results are stable, rapid and accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a schematic structural diagram of a bionic skin structure according to the first embodiment;

[0016] Figure 2 (a) with Figure 2 (b) is a schematic diagram of the working principle of the bionic skin structure according to the first embodiment;

[0017] Figure 3 is a schematic structural diagram of a bionic skin structure according to the second embodiment. DETAILED DESCRIPTION

[0018] The following is an explanation of the implementation of the present application by means of specific embodiments. People familiar with the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification.

[0019] In the following description, reference is made to the accompanying drawings, which describe several embodiments of the present application. It should be understood that other embodiments may be used and that mechanical, structural, electrical, and operational changes may be made without departing from the spirit and scope of the present application. The following detailed description should not be considered limiting, and the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present application.

[0020] Although the terms first, second, etc. are used herein to describe various elements in some instances, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element.

[0021] Furthermore, as used in this article, the singular forms "one", "an" and "the" are intended to include plural forms as well, unless there is an indication to the contrary in the context. It should be further understood that the terms "comprise", "include" indicate the presence of the described features, steps, operations, elements, components, projects, kinds, and / or groups, but do not exclude the presence, occurrence or addition of one or more other features, steps, operations, elements, components, projects, kinds, and / or groups. The terms "or" and "and / or" used herein are interpreted as inclusive, or mean any one or any combination. Therefore, "A, B or C" or "A, B and / or C" means "any of the following: A; B; C; A and B; A and C; B and C; A, B and C". Exceptions to this definition will only occur when the combination of elements, functions, steps or operations is inherently mutually exclusive in some way.

[0022] The bionic skin structure of the present application includes a functional structure and a sensing structure. The sensing structure is located on one side of the functional structure and is electrically connected to the functional structure. The functional structure has an electrostrictive function. When the sensing structure generates an electrical signal change as the environment changes, the functional structure deforms in response to the change in the electrical signal. When the bionic skin structure of the present application is used, the bionic skin structure is installed on a carrier, such as a robotic arm, in such a way that the sensing structure is located on the inner side of the functional structure, so that the surface of the functional structure is equivalent to the skin surface.

[0023] The sensing structure is located on one side of the functional structure. Through the coordination and electrical connection between the mechanical structures, the functional structure can perform structural expansion and contraction feedback based on the sensing changes of the sensing structure, simulating the emergency response of the skin to resist changes in the external environment, thereby structurally imitating the function of the skin. According to the sensing function to be achieved by the sensing structure and the realization of ventilation and breathability, the functional structure can be provided with through holes.

[0024] The functional structure is composed of an electrostrictive material, including but not limited to a dielectric elastomer, a ceramic material, and an ionic polymer composite material, so that the electrostrictive material can expand and contract when a voltage signal and / or a current signal changes.

[0025] The sensing structure includes a conductive material and a sensing material coated on the outside of the conductive material. When the sensing material is deformed with changes in the environment, the cross-sectional size of the conductive material changes and an electrical signal changes. Optionally, the conductive material is liquid metal, conductive polymer or conductive hydrogel, and the sensing material is elastic insulating material, temperature-controlled shape memory polymer or hydrogel material, so that external pressure, temperature and humidity can be sensed. It can be understood that the sensing material is not limited to this, and it only needs to be deformed to change the cross-sectional size of the conductive material when sensing environmental changes. Preferably, the conductive material is selected as liquid metal, which has a small resistance and a fast deformation response, so that the simulation results can be more stable, rapid and accurate.

[0026] The bionic skin structure of the present application is introduced in detail below through different embodiments.

[0027] First embodiment

[0028] Figure 1 FIG. 1 is a schematic diagram of a bionic skin structure according to the first embodiment. Figure 1 As shown, in the bionic skin structure of this embodiment, the functional structure 11 and the sensing structure 12 are connected in parallel with each other. When the sensing structure 12 generates electrical signal changes as the environment changes, the functional structure 11 can quickly respond to the changes in the electrical signal and deform.

[0029] The functional structure 11 includes a central ring body 116 and a plurality of connecting arms, which are arranged at intervals along the circumference of the central ring body 116, the first end of the connecting arm is connected to the central ring body 116, the second end of the connecting arm is fixed, and the second ends of all the connecting arms are electrically connected to the sensing structure 12. The second end of the connecting arm is preferably fixed to the sensing structure 12 and is electrically connected to the sensing structure 12 at the fixed position. The connecting arm is preferably curved, such as a semi-arc, a serpentine or a broken line, so that the functional structure 11 as a whole presents the form of a paper-cut structure, which can improve the deformation amplitude and structural stability. The connecting arm in this embodiment is preferably semi-arc.

[0030] In this embodiment, there are four connecting arms, namely, the first connecting arm 111, the second connecting arm 112, the third connecting arm 113 and the fourth connecting arm 114, each of which has a first end connected to the central ring body 116 and a second end away from the central ring body 116. The first end of the first connecting arm 111, the first end of the second connecting arm 112, the first end of the third connecting arm 113 and the first end of the fourth connecting arm 114 are mutually conductive through the central ring body 116, and the second end of the first connecting arm 111, the second end of the second connecting arm 112, the second end of the third connecting arm 113 and the second end of the fourth connecting arm 114 are all electrically connected to the sensing structure 12, so that the functional structure 11 and the sensing structure 12 are connected in parallel.

[0031] The sensing structure 12 includes a plurality of sensing branches, the first ends of the plurality of sensing branches are connected to each other, and the second ends of the plurality of sensing branches are electrically connected to the second ends of the plurality of connecting arms in a one-to-one correspondence. In this embodiment, the first ends of the plurality of sensing branches are connected to each other, and the connection between the first ends of the plurality of sensing branches coincides with the projection of the center point of the central ring body 116. Preferably, the sensing structure 12 is a cross structure, thereby forming a first sensing branch 121, a second sensing branch 122, a third sensing branch 123 and a fourth sensing branch 124, and the central intersection 125 of the cross structure coincides with the projection of the central point of the central ring body 116. The central intersection 125 is also the connection point between the first end of the first sensing branch 121, the first end of the second sensing branch 122, the first end of the third sensing branch 123 and the first end of the fourth sensing branch 124, and the second end of the first sensing branch 121, the second end of the second sensing branch 122, the second end of the third sensing branch 123 and the second end of the fourth sensing branch 124 are also the ends away from the central intersection 125.

[0032] The second end of each connecting arm corresponds to an end of the sensing structure 12, that is, the second end of the first connecting arm 111 and the second end of the first sensing branch 121 are fixed and electrically connected to each other, the second end of the second connecting arm 112 and the second end of the second sensing branch 122 are fixed and electrically connected to each other, the second end of the third connecting arm 113 and the second end of the third sensing branch 123 are fixed and electrically connected to each other, and the second end of the fourth connecting arm 114 and the second end of the fourth sensing branch 124 are fixed and electrically connected to each other. Among the four fixed connection points, at least one fixed connection point is a current input end, and the remaining fixed connection points are current output ends.

[0033] The sensing structure 12 includes a conductive material and a sensing material coated on the outside of the conductive material. When the sensing material is deformed with changes in the environment, the cross-sectional size of the conductive material changes and an electrical signal changes. Optionally, the conductive material is liquid metal, conductive polymer or conductive hydrogel, and the sensing material is elastic insulating material, temperature-controlled shape memory polymer or hydrogel material, so that external pressure, temperature and humidity can be sensed. It can be understood that the sensing material is not limited to this, and it only needs to be deformed to change the cross-sectional size of the conductive material when sensing environmental changes. Preferably, the conductive material is selected as liquid metal, which has a small resistance and a fast deformation response, so that the simulation results can be more stable, rapid and accurate.

[0034] like Figure 2 As shown in (a), take the stimulation of the bionic skin structure by an external object 10 as an example. The external object 10 includes but is not limited to a thin needle, a thin wooden stick, etc. When the external object 10 does not penetrate the bionic skin structure, the sensing structure 12 and the functional structure 11 are close to each other, and the current passes through the sensing structure 12, short-circuiting the functional structure 11. The functional structure 11 does not deform without current stimulation. Figure 1 and Figure 2 (b), when the external object 10 penetrates the central ring body 116 of the sensing structure 12, the sensing structure 12 located inside the functional structure 11 is squeezed, so that the cross-sectional size of the sensing structure 12 is rapidly reduced, and the resistance is increased to achieve the circuit-breaking effect. At this time, the current passes through the functional structure 11, causing the functional structure 11 to undergo electrostriction and deformation. The central ring body 116 and the connecting arm of the functional structure 11 undergo different deformations, so that the functional structure 11 undergoes three-dimensional deformation, wherein the central ring body 116 expands to shrink the hollow part and clamp the external object 10. At the same time, the first connecting arm 111, the second connecting arm 112, the third connecting arm 113 and the fourth connecting arm 114 extend and lengthen, and push the central ring body 116 to push the external object 10 outward by lifting. When the external object 10 is pushed out a certain distance, the sensing structure 12 is no longer squeezed, and the cross-sectional size returns to normal. The current passes through the sensing structure 12, and the functional structure 11 is short-circuited again. At this time, the process of pushing out the external object 10 stops, realizing the response of the bionic skin structure to external stimuli. The deformation range of the functional structure 11 can be designed by adjusting structural parameters such as the size and thickness of the central ring body 116 and the length and thickness of the connecting arm.

[0035] In order to achieve the above simulation effect of external object stimulation, the functional structure 11 can be composed of electrostrictive materials such as polyacrylate elastomer doped with aluminum nanoparticles, lead zirconate titanate ceramic material or IPMC ion polymer composite material. The conductive material in the sensing structure 12 is preferably liquid metal. In the case where there is no external object squeezing and blocking the liquid metal, the resistance of the liquid metal is much smaller than the resistance of the electrostrictive material, so that the functional structure 11 can be short-circuited. In addition, the liquid metal can be quickly and completely blocked when squeezed by an external object, and can quickly restore its original shape after the external object leaves, with a fast response speed. The sensing material in the sensing structure 12 is preferably polydimethylsiloxane (PDMS), which can protect the liquid metal. At the same time, when squeezed by an external object, the PDMS deforms, so that the liquid metal inside is blocked. When the external object leaves, the PDMS deforms and recovers, so that the liquid metal inside regains continuity. When making the sensing structure 12, liquid metal can be printed by 3D printing, and the shape is a cross structure with a length of 15-30mm and a cross-sectional radius of 0.05-1mm. After the liquid metal is formed, it is coated with PDMS material to obtain the sensing structure 12. When making the functional structure 11, the electrostrictive material is made into a paper-cut structure, and the diameter of the connecting arm and the central ring body 116 is 5-10mm and the width is 0.5-2mm. Finally, the connecting arms of the functional structure 11 are fixed to the corresponding ends of the sensing structure 12 to achieve conduction, and the fixed parts are coated with PDMS to obtain a bionic skin structure.

[0036] In order to achieve the response to the change of ambient temperature, the sensing material in the sensing structure 12 can be a temperature-controlled shape memory polymer PEG doped material, and the conductive material in the sensing structure 12 is preferably liquid metal. The functional structure 11 can be composed of electrostrictive materials such as polyacrylate elastomer doped with aluminum nanoparticles, lead zirconate titanate ceramic material or IPMC ion polymer composite material. When making the sensing structure 12, the liquid metal can be printed by 3D printing, and the shape is a cross structure with a length of 15-30mm and a cross-sectional radius of 0.05-1mm. After the liquid metal is formed, it is coated with a temperature-controlled shape memory polymer PEG doped material to obtain the sensing structure 12, and the temperature-controlled deformation temperature is 38°C. When making the functional structure 11, the electrostrictive material is made into a paper-cut structure, and the diameter of the connecting arm and the central ring body 116 is 5-10mm and the width is 0.5-2mm. Finally, each connecting arm of the functional structure 11 is fixed correspondingly to each end point of the sensing structure 12 to achieve conduction, and the fixed part is coated with PDMS to obtain a bionic skin structure that can respond to changes in ambient temperature.

[0037] When the ambient temperature is lower than 38°C, the temperature-controlled shape memory polymer does not deform, the sensing structure 12 and the functional structure 11 are close to each other, and the current passes through the sensing structure 12, short-circuiting the functional structure 11. The functional structure 11 does not deform without current stimulation. When the ambient temperature is higher than 38°C, the temperature-controlled shape memory polymer deforms, squeezing the liquid metal inside, causing the cross-sectional size of the liquid metal to decrease rapidly, and the resistance to increase to achieve a circuit-breaking effect. At this time, the current passes through the functional structure 11, causing the functional structure 11 to deform due to electrostriction. The central ring body 116 and the connecting arm of the functional structure 11 deform differently, so that the functional structure 11 deforms in three dimensions, wherein the central ring body 116 expands to shrink the hollow part, and at the same time, the first connecting arm 111, the second connecting arm 112, the third connecting arm 113 and the fourth connecting arm 114 extend and lengthen, and the central ring body 116 is pushed outward by lifting, thereby increasing the heat dissipation area near the skin structure, which can accelerate the convective heat dissipation and the evaporation rate of water. When the temperature of the temperature-controlled shape memory polymer is lowered through convection and water evaporation rate, the temperature-controlled shape memory polymer restores its deformation, the liquid metal is no longer squeezed, the cross-sectional size returns to normal, and the current passes through the sensing structure 12, short-circuiting the functional structure 11 again, thereby realizing the response of the bionic skin structure to changes in ambient temperature.

[0038] In order to achieve the response to the change of environmental humidity, the sensing material in the sensing structure 12 can be a hydrogel material, and the hydrogel material includes but is not limited to poly L-lysine, poly L-glutamic acid, polyacrylic acid, polymethacrylic acid, polyacrylamide, poly N-polyacrylamide, etc. The conductive material in the sensing structure 12 is preferably a liquid metal. The functional structure 11 can be composed of electrostrictive materials such as polyacrylate elastomer doped with aluminum nanoparticles, lead zirconate titanate ceramic material or IPMC ion polymer composite material. When making the sensing structure 12, the liquid metal can be printed by 3D printing, and the shape is a cross structure with a length of 15-30mm and a cross-sectional radius of 0.05-1mm. After the liquid metal is formed, it is coated with a hydrogel material to obtain the sensing structure 12. At this time, the hydrogel material is in a water-deficient shrinkage state. When making the functional structure 11, the electrostrictive material is made into a paper-cut structure, and the diameter of the connecting arm and the central ring body 116 is 5-10mm and the width is 0.5-2mm. Finally, each connecting arm of the functional structure 11 is fixed correspondingly to each end point of the sensing structure 12 to achieve conduction, and the fixed part is coated with PDMS to obtain a bionic skin structure that can respond to changes in environmental humidity.

[0039] When the ambient humidity is within a certain range, the hydrogel material will not absorb water and swell, the sensing structure 12 and the functional structure 11 are close to each other, and the current passes through the sensing structure 12, short-circuiting the functional structure 11. The functional structure 11 does not deform without current stimulation. When the ambient humidity increases, the hydrogel material absorbs water and swells, squeezing the liquid metal inside, causing the cross-sectional size of the liquid metal to decrease rapidly, and the resistance increases to achieve a circuit-breaking effect. At this time, the current passes through the functional structure 11, causing the functional structure 11 to deform due to electrostriction. The central ring body 116 and the connecting arm of the functional structure 11 undergo different deformations, thereby causing the functional structure 11 to deform in three dimensions, wherein the central ring body 116 expands to shrink the hollow part, and at the same time, the first connecting arm 111, the second connecting arm 112, the third connecting arm 113 and the fourth connecting arm 114 extend and lengthen, and the central ring body 116 is pushed outward by lifting, forming a convection channel near the skin structure, which can accelerate the evaporation rate of water. When the moisture in the hydrogel material is reduced through convection and the evaporation rate of water, the hydrogel material shrinks and deforms, the liquid metal is no longer squeezed, the cross-sectional size returns to normal, and the current passes through the sensing structure 12, short-circuiting the functional structure 11 again, thereby realizing the response of the bionic skin structure to changes in environmental humidity.

[0040] The bionic skin structure of this embodiment includes a functional structure and a sensing structure. The sensing structure is located on one side of the functional structure and is electrically connected to the functional structure. The functional structure has an electrostrictive function. When the sensing structure generates an electrical signal change with a change in the environment, the functional structure deforms in response to the change in the electrical signal. The present application electrically connects the functional structure with the electrostrictive function with the sensing structure that can generate an electrical signal change. When the sensing structure generates an electrical signal change with a change in the environment, the emergency response of the skin to the environmental change can be simulated by the expansion and contraction change of the functional structure. In addition, through the sensing between the mechanical structures, the simulation results are stable, rapid and accurate.

[0041] Second embodiment

[0042] Figure 3 FIG. 1 is a schematic diagram of a bionic skin structure according to the second embodiment. Figure 3 As shown, in the bionic skin structure of this embodiment, the functional structure 21 and the sensing structure 22 are connected in series. When the sensing structure 22 generates electrical signal changes as the environment changes, the functional structure 21 can respond to the changes in the electrical signal and deform in time.

[0043] The functional structure 21 includes a central ring body 216 and a plurality of connecting arms, which are arranged at intervals along the circumference of the central ring body 216, the first end of the connecting arm is connected to the central ring body 216, the second end of the connecting arm is fixed, and the second end of some connecting arms is electrically connected to the sensing structure 22. The second end of the connecting arm is preferably fixed to the sensing structure 22 and is electrically connected to the sensing structure 22 at the fixed position. The connecting arm is preferably curved, such as a semi-arc, so that the functional structure 21 as a whole presents the shape of a paper-cut structure, which can improve the deformation amplitude and structural stability.

[0044] In this embodiment, there are four connecting arms, namely the fifth connecting arm 211, the sixth connecting arm 212, the seventh connecting arm 213 and the eighth connecting arm 214, each of which has a first end connected to the central ring body 216 and a second end away from the central ring body 216. The central ring body 216 is divided into at least two ring segments by the insulating portion 2163, and in this embodiment, it is divided into a first ring segment 2161 and a second ring segment 2162, each of which is connected to two connecting arms, wherein the first ring segment 2161 is connected to the fifth connecting arm 211 and the sixth connecting arm 212, and the second ring segment 2162 is connected to the seventh connecting arm 213 and the eighth connecting arm 214.

[0045] The sensing structure 22 includes at least two sensing parts, and the present embodiment includes a first sensing part 221 and a second sensing part 222. Preferably, the sensing structure 22 is a cross structure, that is, the first sensing part 221 and the second sensing part 222 are cross-crossed and are not conductive to each other at the intersection. The central intersection point of the cross structure coincides with the projection of the central point of the central ring body 216. The ends of the first sensing part 221 and the second sensing part 222 are also the ends of the sensing structure 22, and the second end of each connecting arm corresponds to an end of the sensing structure 22.

[0046] The ring segments and the sensing parts are arranged alternately, that is, the ring segments and the sensing parts are electrically connected in the order of the first sensing part 221, the first ring segment 2161, the second sensing part 222, and the second ring segment 2162. The second ends of the connecting arms connecting the same ring segment are electrically connected to the ends of different sensing parts respectively, and the second end of one of the multiple connecting arms is insulated from the end of the corresponding sensing part for connecting to an external circuit, so that the functional structure 21 and the sensing structure 22 are connected in series. In this embodiment, the second end of the seventh connecting arm 213 is connected to the external circuit as a current input end, the end of the first sensing part 221 corresponding to the seventh connecting arm 213 is connected to the external circuit as a current output end, the second end of the fifth connecting arm 211 is fixed and electrically connected to the other end of the first sensing part 221, the second end of the sixth connecting arm 212 is fixed and electrically connected to one end of the second sensing part 222, and the second end of the eighth connecting arm 214 is fixed and electrically connected to the other end of the second sensing part 222.

[0047] The sensing structure 22 includes a conductive material and a sensing material coated on the outside of the conductive material. When the sensing material is deformed with changes in the environment, the cross-sectional size of the conductive material changes and an electrical signal change is generated. Optionally, the conductive material is liquid metal, conductive polymer or conductive hydrogel, and the sensing material is elastic insulating material, temperature-controlled shape memory polymer or hydrogel material, so that external pressure, temperature and humidity can be sensed. It can be understood that the sensing material is not limited to this, and it only needs to be deformed to change the cross-sectional size of the conductive material when sensing environmental changes. The sensing structure 22 and the functional structure 21 are connected in series, and the sensing structure 22 only needs to deform to a certain extent to cause the expansion and contraction changes of the functional structure 21, thereby increasing the selection range of the conductive material in the sensing structure 22.

[0048] Taking the response to the change of environmental humidity as an example, the sensing material in the sensing structure 22 can be a hydrogel material, and the hydrogel material includes but is not limited to poly-L-lysine, poly-L-glutamic acid, polyacrylic acid, polymethacrylic acid, polyacrylamide, poly-N-polyacrylamide, etc. The conductive material in the sensing structure 22 can be selected from liquid metal or conductive polymer. The functional structure 21 can be composed of electrostrictive materials such as polyacrylate elastomer doped with aluminum nanoparticles, lead zirconate titanate ceramic material or IPMC ion polymer composite material. When making the sensing structure 22, taking the conductive material as liquid metal as an example, the liquid metal can be printed by 3D printing, and the shape is a cross structure, the length is 15-30mm, and the cross-sectional radius is 0.05-1mm. After the liquid metal is formed, it is coated with a hydrogel material to obtain the sensing structure 22. At this time, the hydrogel material is in a state of water shortage and contraction. When making the functional structure 21, the electrostrictive material is made into a paper-cut structure, and the diameter of the connecting arm and the central ring body 216 is 5-10mm and the width is 0.5-2mm. Finally, three of the connecting arms of the functional structure 21 are fixed to the corresponding end points of the sensing structure 22 to achieve conduction in series, and the fixed parts are coated with PDMS. The remaining connecting arm and the end of the sensing structure 22 are connected to the positive and negative power sources, thereby obtaining a bionic skin structure that can respond to changes in environmental humidity.

[0049] In the initial state, since the liquid metal has a small resistance and is connected in series with the electrostrictive material, the current passing through the electrostrictive material is large, causing deformation, so that it can deform when the external humidity is high, accelerate the water absorption rate of the hydrogel material, and cause the hydrogel material to expand. After the hydrogel material absorbs water and expands, the expanded hydrogel material squeezes the liquid metal inside, making the liquid metal thinner, so that the resistance becomes larger or even a circuit break occurs. At this time, the current in the circuit becomes smaller or no current passes, and the electrostrictive material returns to its original state, causing the water absorption rate of the hydrogel material to slow down or even stop. When the hydrogel material gradually loses water, the hydrogel material returns from the expanded state to the contracted state, the liquid metal gradually recovers continuity from the circuit break, the current in the circuit becomes larger again, the electrostrictive material deforms, and the water absorption area of ​​the hydrogel material is expanded again. This cycle realizes the response of the bionic skin structure to changes in environmental humidity.

[0050] The bionic skin structure of this embodiment includes a functional structure and a sensing structure. The sensing structure is located on one side of the functional structure and is electrically connected to the functional structure. The functional structure has an electrostrictive function. When the sensing structure generates an electrical signal change with a change in the environment, the functional structure deforms in response to the change in the electrical signal. The present application electrically connects the functional structure with the electrostrictive function with the sensing structure that can generate an electrical signal change. When the sensing structure generates an electrical signal change with a change in the environment, the emergency response of the skin to the environmental change can be simulated by the expansion and contraction change of the functional structure. In addition, through the sensing between the mechanical structures, the simulation results are stable, rapid and accurate.

[0051] The above embodiments are merely illustrative of the principles and effects of the present application and are not intended to limit the present application. Anyone familiar with the technology may modify or change the above embodiments without violating the spirit and scope of the present application. Therefore, all equivalent modifications or changes made by a person of ordinary skill in the art without departing from the spirit and technical ideas disclosed in the present application shall still be covered by the claims of the present application.

Claims

1. A bionic skin structure, characterized in that: It includes a functional structure and a sensing structure, wherein the sensing structure is located on one side of the functional structure and is electrically connected to the functional structure, and the functional structure has an electrostrictive function. When the sensing structure generates an electrical signal change as the environment changes, the functional structure deforms in response to the change of the electrical signal. The functional structure includes a central ring body and a plurality of connecting arms, wherein the plurality of connecting arms are arranged at intervals along the circumference of the central ring body, the first end of the connecting arm is connected to the central ring body, the second end of the connecting arm is fixed to one end of the sensing structure, and the second ends of the plurality of connecting arms are electrically connected to the sensing structure in whole or in part.

2. The bionic skin structure according to claim 1, characterized in that: The first ends of the plurality of connecting arms are electrically connected to each other through the central ring body, and the second ends of the plurality of connecting arms are electrically connected to the sensing structure.

3. The bionic skin structure according to claim 2, characterized in that: The sensing structure includes a plurality of sensing branches, the first ends of the plurality of sensing branches are electrically connected to each other, and the second ends of the plurality of sensing branches are electrically connected to the second ends of the plurality of connecting arms in a one-to-one correspondence.

4. The bionic skin structure according to claim 3, characterized in that: The first ends of the plurality of sensing branches are interconnected and conductive, and the connection points between the first ends of the plurality of sensing branches coincide with the projection of the center point of the central ring body.

5. The bionic skin structure according to claim 1, characterized in that: The central ring body is divided into at least two ring segments by an insulating part, each ring segment is respectively connected to two of the connecting arms, the sensing structure includes at least two sensing parts, the ring segments and the sensing parts are alternately arranged, the second ends of the connecting arms connected to the same ring segment are respectively electrically connected to the ends of different sensing parts, and the second end of a connecting arm among the multiple connecting arms is insulated from the end of the corresponding sensing part for connecting to an external circuit.

6. The bionic skin structure according to claim 1, characterized in that: The second end of the connecting arm is fixed on the sensing structure, and / or the connecting arm is curved.

7. The bionic skin structure according to any one of claims 1 to 6, characterized in that: The sensing structure is a cross structure, the central intersection of the cross structure coincides with the projection of the central point of the central ring body, the number of the connecting arms is 4, and the second end of each connecting arm corresponds to an end of the sensing structure.

8. The bionic skin structure according to claim 1, characterized in that: The sensing structure includes a conductive material and a sensing material coated outside the conductive material. When the sensing material is deformed with changes in the environment, the cross-sectional size of the conductive material changes to generate changes in electrical signals.

9. The bionic skin structure according to claim 8, characterized in that: The conductive material is liquid metal, conductive polymer or conductive hydrogel, and the sensing material is elastic insulating material, temperature-controlled shape memory polymer or hydrogel material.

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