Pressure sensor and robot

Abstract

The utility model relates to a pressure sensor, a robot and an executive component applied to the robot, the executive component comprises a base body, the shape of the projection of the base body along the thickness direction is the same as that of a hand, the base body is provided with a palm area, a finger area and a wrist area, and the pressure sensor comprises a sensing unit. The sensitive module comprises a plurality of sensitive modules arranged in the palm area and the finger area; each sensitive module comprises a plurality of sensitive assemblies, and each sensitive assembly comprises a substrate, a lower electrode, a composite sensitive layer, an upper electrode and a packaging layer which are sequentially arranged in the thickness direction; the composite sensitive layer comprises a corrugated layer and a film layer, and the corrugated layer and the film layer are attached to each other to form a corrugated structure; the lead unit comprises an upper electrode lead, a lower electrode lead, a common lead and a total output end. The capacitive flexible tactile sensor can solve the problems that an existing capacitive flexible tactile sensor is low in force perception precision, and sensitivity and linearity are reduced along with increase of pressure.

Description

TECHNICAL FIELD

[0001] The utility model relates to sensor technical field especially is a kind of pressure sensor and robot. BACKGROUND

[0002] With the continuous iteration and upgrading of robot technology, the performance breakthrough of key components of humanoid robots becomes the focus of urgent improvement. In the design and development of robots, in order to realize highly anthropomorphic operation and interaction, the hand as a key actuator plays a very key role, and the robot performs various fine tasks through the dexterous hand and obtains environmental information. The hand of the robot realizes accurate perception of the environment through the sensing system configured thereon. Therefore, the hand of the robot needs to be configured with a flexible tactile sensor with high sensitivity and large range. The flexible tactile sensor applied to the hand of the robot is made of flexible materials (such as elastomers, conductive polymers, and nanomaterials) based on bionics research on human skin, has the characteristics of bendable and thin and attached, can perceive and quantify the physical stimulus applied to its surface, and convert these information into electrical signal output. The common tactile sensors on the market include piezoresistive, capacitive, piezoelectric, triboelectric, etc., which respectively detect pressure based on different principles. In the prior art, the piezoelectric tactile sensor based on self-assembled electrospun micro-pyramid array developed by Beijing Nano Energy and System Research Institute is prepared by electrospinning and plated with gold as electrode, with sensitivity of 19 kPa and response time of 0.8 ms; Tsinghua University developed a piezoresistive tactile sensor based on laser-engraved porous graphene embedding, which uses the porous structure of graphene to deform when pressed, causing resistance change, thereby realizing high-sensitivity pressure detection, suitable for electronic skin and human-computer interaction applications; in addition, a flexible pressure sensor based on liquid metal developed by a Korean research team prepares liquid metal microchannels and rigid micro-bump arrays through one-step direct process, with sensitivity of about 0.158 kPa, and has repeatable pressure response and negligible hysteresis under fatigue stimulation; in addition, other research teams developed a multifunctional pressure sensor based on carbon black sponge, which realizes micro-crack design through layer-by-layer assembly, meeting the monitoring needs of ultra-small and large-scale moving objects. A piezoresistive pressure sensor based on carbon nanofiber / polydimethylsiloxane foam composite material with hierarchical pore structure is proposed by a research team of Hangzhou Normal University, which has good sensitivity and reliability. However, the piezoresistive pressure sensor is still only suitable for finger tip part, and cannot effectively perceive the pressure information of palm part.

[0003] However, the prior art is limited to the research on the tactile enhancement of the local area of the fingertip of the robot finger, and the tactile perception of the whole hand (including the fingers and the palm) lacks systematic detection, so that the robot hand cannot accurately perceive the force and the object state in the state of gripping, clamping and the like; in addition, the existing sensor generally adopts an array layout in the design, which is usually composed of a plurality of high-precision and high-performance sensitive units arranged in a certain order. Due to the large number of sensitive units and the complex distribution of the sensitive units, the wiring of the sensor becomes more complex, which on the one hand leads to an increase in design difficulty, and on the other hand, the requirement for the manufacturing process is also more stringent; and since the capacitive sensor mainly relies on the distance change of the two polar plates when pressure is applied to measure the pressure, due to the limitation of the structure, when the pressure increases to a certain extent, the distance change of the polar plate is small, and the sensitivity will decrease rapidly with the increase of the pressure, thereby leading to poor linearity and further reducing the accuracy of the measurement result. Practical new type content

[0004] Therefore, the technical problem to be solved by the utility model lies in overcoming the deficiencies in the prior art, providing a pressure sensor and a robot, solving the problems of lack of perception ability of the parts of the robot fingers except the fingertips and the palm parts and the decrease of sensitivity and linearity with the increase of pressure, realizing high-precision and high-sensitivity pressure perception of the whole hand, and ensuring good sensitivity and linearity when the pressure increases.

[0005] To solve the above technical problems, the utility model provides a pressure sensor applied to an execution component of a robot, the execution component comprising a base body, a projection of the base body along a thickness direction being the same as the shape of a hand, the base body having a palm area, a finger area and a wrist area, the pressure sensor comprising,

[0006] a sensing unit comprising a plurality of sensitive modules arranged in the palm area and the finger area; each sensitive module comprising a plurality of sensitive components, each sensitive component comprising, in sequence along the thickness direction, a substrate, a lower electrode, a composite sensitive layer, an upper electrode and an encapsulation layer; the composite sensitive layer comprising a corrugated layer and a film layer, the corrugated layer and the film layer being mutually adhered to form a corrugated structure;

[0007] A lead unit is connected to the sensing unit to output the sensing signal of the sensing unit; the lead unit comprises an upper electrode lead, a lower electrode lead, a common lead and a total output terminal; each of the upper electrodes is connected to the total output terminal through the upper electrode lead, each of the lower electrodes is connected to the common lead through the lower electrode lead, and the end of the common lead is connected to the total output terminal; the total output terminal is arranged at the wrist area; in the same sensitive module, the upper electrode lead is connected to one side of the sensitive component, and the lower electrode lead and the common lead are connected to the other side of the sensitive component;

[0008] A control unit is connected to the sensing unit through the lead unit, the control unit receives the sensing signal, and the sensing signal is converted into a pressure signal output after data processing.

[0009] In an embodiment of the present application, the sensing unit comprises a first sensitive module, a second sensitive module, a third sensitive module, a fourth sensitive module and a fifth sensitive module; the first sensitive module is located at the area of the little finger on the base and the palm area; the second sensitive module is located at the area of the ring finger on the base and the palm area; the third sensitive module is located at the area of the middle finger on the base and the palm area; the fourth sensitive module is located at the area of the index finger on the base and the palm area; and the fifth sensitive module is located at the area of the thumb on the base and the palm area.

[0010] In an embodiment of the present application, the first sensitive module comprises a first sensitive component, a second sensitive component, a third sensitive component and a fourth sensitive component; the second sensitive module comprises a fifth sensitive component, a sixth sensitive component, a seventh sensitive component, an eighth sensitive component and a ninth sensitive component; the third sensitive module comprises a tenth sensitive component, an eleventh sensitive component, a twelfth sensitive component and a thirteenth sensitive component; the fourth sensitive module comprises a fourteenth sensitive component, a fifteenth sensitive component and a sixteenth sensitive component; and the fifth sensitive module comprises a seventeenth sensitive component, an eighteenth sensitive component and a nineteenth sensitive component.

[0011] In an embodiment of the present application, the lower electrode is formed on the base by graphic printing; the composite sensitive layer is arranged on the lower electrode, one side of the upper electrode is attached to the composite sensitive layer, and the other side of the upper electrode is attached to the packaging layer.

[0012] In an embodiment of the present application, the packaging layer is packaged by low-temperature compression with the upper electrode, the composite sensitive layer, the lower electrode and the base.

[0013] In an embodiment of the utility model, the lower electrode and the composite sensitive layer are circular, the composite sensitive layer is concentrically arranged with the lower electrode, and the diameter of the lower electrode is smaller than that of the composite sensitive layer.

[0014] In an embodiment of the utility model, the wrinkle layer comprises a first capacitor C1 and a second capacitor C2; the film layer comprises a third capacitor C3; the first capacitor C1 and the second capacitor C2 are connected in parallel, and then connected in series with the third capacitor C3.

[0015] In an embodiment of the utility model, the first capacitor C1 is a capacitor with a vacuum dielectric layer, the second capacitor C2 is a capacitor with a wrinkled multi-walled carbon nanotube / polydimethylsiloxane composite film dielectric layer, and the third capacitor C3 is a capacitor with a planar multi-walled carbon nanotube / polydimethylsiloxane composite film dielectric layer.

[0016] In an embodiment of the utility model, the upper electrode is an ITO / PET film, and the packaging layer is a polydimethylsiloxane film.

[0017] The utility model also provides a robot, including robot body, execution part and the pressure sensor as described above, the pressure sensor is installed in the execution part.

[0018] The above technical scheme of the utility model has the following advantages compared with the prior art:

[0019] The pressure sensor can be applied to the execution part of the robot, specifically, can be applied to a humanoid robot with a dexterous hand structure. The pressure sensor comprises a sensing unit, a lead unit and a control unit. The sensing unit comprises a plurality of sensitive modules, which are reasonably arranged in the finger area and the palm area, thereby achieving comprehensive coverage of the entire hand sensing area. Each sensitive module comprises a plurality of sensitive components, each sensitive component comprises a substrate, a lower electrode, a composite sensitive layer, an upper electrode and a packaging layer, wherein the composite sensitive layer forms a wrinkle structure, thereby maintaining high sensitivity and linearity when the external pressure received by the pressure sensor increases. Based on the working principle of the capacitor, the relationship between the capacitor capacity and the distance between the plates and the dielectric constant is utilized to achieve accurate perception of the force position and the force size. At the same time, the lead unit of the pressure sensor reduces the setting of the lead by setting a common lead, simplifies the circuit layout, and to some extent, avoids the interference problem in the local motion process of the hand. The capacitive flexible tactile pressure sensor has the advantages of low cost, compact structure, high sensitivity, etc., and can solve the problems of low force perception accuracy, and the decrease of sensitivity and linearity with the increase of pressure of the existing capacitive flexible tactile sensor. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to make the content of the utility model more easily be clearly understood, the following according to the specific embodiment of the utility model and combining with the drawings, the utility model is further explained in detail, wherein.

[0021] Figure 1 It is the plan view of the pressure sensor of the preferred embodiment of the utility model being attached to the hand.

[0022] Figure 2 It is the partial structure schematic view of the first sensitive module of the preferred embodiment of the utility model.

[0023] Figure 3 It is the lead distribution schematic view of the wrist area of the preferred embodiment of the utility model (corresponding to Figure 6 ).

[0024] Figure 4 It is the explosion schematic view of the sensitive assembly of the preferred embodiment of the utility model.

[0025] Figure 5 It is the equivalent circuit diagram of the pressure sensor of the preferred embodiment of the utility model.

[0026] Figure 6 It is the partial structure enlarged view of A of Figure 1 .

[0027] Figure 7 It is the partial structure enlarged view of the finger area of Figure 1 .

[0028] Description of the drawing mark of the specification: 10, base; 11, lower electrode; 12, composite sensitive layer; 13, upper electrode; 14, encapsulation layer; 21, first sensitive assembly; 22, second sensitive assembly; 23, third sensitive assembly; 24, fourth sensitive assembly; 25, fifth sensitive assembly; 26, sixth sensitive assembly; 27, seventh sensitive assembly; 28, eighth sensitive assembly; 29, ninth sensitive assembly; 210, tenth sensitive assembly; 211, eleventh sensitive assembly; 212, twelfth sensitive assembly; 213, thirteenth sensitive assembly; 214, fourteenth sensitive assembly; 215, fifteenth sensitive assembly; 216, sixteenth sensitive assembly; 217, seventeenth sensitive assembly; 218, eighteenth sensitive assembly; 219, nineteenth sensitive assembly. Specific embodiment

[0029] The utility model is further explained in the following combining with the drawings and specific embodiment, so that the person skilled in the art can better understand the utility model and can be implemented, but the embodiment is not as the limitation of the utility model.

[0030] In the development process of humanoid robots, a flexible pressure sensor with good linearity and sensitivity is a necessary condition for realizing good tactile perception. The rest of the fingers and the palm serve as a load-bearing structure to support the operation of the fingertip, and therefore, the pressure perception performance of the rest of the fingers and the palm is also crucial for improving the overall perception interaction performance of the robot hand.

[0031] Embodiment one of the utility model discloses a kind of pressure sensors, applied to the execution component of robot, the execution component includes base body, the projection of the base body along thickness direction is identical with the shape of human hand.Accordingly, the base body has palm area, finger area and wrist area.

[0032] Referring to Figures 1 to 5 As shown, the pressure sensor includes a sensing unit, and the sensing unit includes a plurality of sensitive modules arranged in the palm area and the finger area.

[0033] It should be noted that the plurality of sensitive modules can cover and fit the palm area and the finger area of the base body, and are reasonably distributed at the finger joint parts, the finger tip parts and the palm area of the base body.

[0034] Specifically, each sensitive module includes a plurality of sensitive components.

[0035] Each sensitive component includes, in sequence along the thickness direction, a substrate 10, a lower electrode 11, a composite sensitive layer 12, an upper electrode 13 and an encapsulation layer 14, and the substrate 10, the lower electrode 11, the composite sensitive layer 12, the upper electrode 13 and the encapsulation layer 14 are tightly pressed to form the sensitive component to perceive external pressure; wherein the composite sensitive layer 12 includes a corrugated layer and a film layer, and the corrugated layer and the film layer are mutually fitted to form a corrugated structure.

[0036] The pressure sensor further includes a lead unit, and the lead unit is connected to the sensing unit to output the sensing signal of the sensing unit.

[0037] The lead unit includes an upper electrode lead, a lower electrode lead, a common lead and a total output end; the total output end is arranged at the wrist area. Each upper electrode 13 is connected to the total output end through the upper electrode lead, each lower electrode 11 is connected to the common lead through the lower electrode lead, and the end of the common lead is connected to the total output end.

[0038] It should be noted that in the same sensitive module, the upper electrode lead is connected to one side of the sensitive component, and the lower electrode lead and the common lead are connected to the other side of the sensitive component; in this way, the leads can be prevented from being intertwined and interfered with, the number of lead wiring is reduced while maintaining signal integrity, the wiring space is significantly compressed, and the overall circuit is simplified.

[0039] The pressure sensor further comprises a control unit connected to the sensing unit through the lead unit, which receives the sensing signal and converts it into a pressure signal output after data processing.

[0040] Therefore, it can be known that the pressure sensor to be protected by the utility model can be applied to the execution component of a robot, specifically, can be applied to a humanoid robot with a dexterous hand structure, the pressure sensor comprises a sensing unit, a lead unit and a control unit, the sensing unit comprises a plurality of sensitive modules, and the plurality of sensitive modules are reasonably arranged in the finger region and the palm region, thereby realizing relatively comprehensive coverage of the whole hand sensing region; each sensitive module comprises a plurality of sensitive components, each sensitive component comprises a substrate 10, a lower electrode 11, a composite sensitive layer 12, an upper electrode 13 and an encapsulation layer 14, wherein the composite sensitive layer 12 is formed with a wrinkle structure, so that the pressure sensor can also maintain high sensitivity and linearity when the external pressure received by the pressure sensor increases, based on the working principle of the capacitor, the relationship between the capacitor capacitance and the distance between the plates and the dielectric constant is utilized, the accurate perception of the force position and the force size is realized; meanwhile, the lead unit of the pressure sensor reduces the setting of the lead by setting the common lead, is more compact in circuit layout, and to some extent, avoids the interference problem in the local motion process of the hand. The capacitive flexible tactile pressure sensor of the utility model has the advantages of low cost, compact structure, high sensitivity and the like, and can solve the problems of low force perception accuracy, and the decrease of sensitivity and linearity with the increase of pressure of the existing capacitive flexible tactile sensor.

[0041] Further, the lead layout mode of the "combined lead" solves the pain points of complex sensor wiring and high manufacturing process requirements; by integrating the same polarity electrode lead into a common lead, the 38 leads required by the traditional scheme are reduced to 23, greatly reducing the wiring density.

[0042] Further, the utility model discloses through " wrinkle layer-film layer " synergistic mechanism realizes full range high linearity response, effectively avoided the problem that the sensitivity and linearity of existing capacitive sensor decline with pressure increase, ensure that robot hand can obtain accurate tactile feedback under different pressure conditions, significantly improve the reliability and adaptability of gripping control.

[0043] As a preferred embodiment, the sensing unit includes a first sensitive module, a second sensitive module, a third sensitive module, a fourth sensitive module, and a fifth sensitive module.

[0044] The first sensitive module is located in the area of the little finger and the palm area on the base body; the second sensitive module is located in the area of the ring finger and the palm area on the base body; the third sensitive module is located in the area of the middle finger and the palm area on the base body; the fourth sensitive module is located in the area of the index finger and the palm area on the base body; and the fifth sensitive module is located in the area of the thumb and the palm area on the base body.

[0045] Specifically, the first sensitive module includes a first sensitive component 21, a second sensitive component 22, a third sensitive component 23, and a fourth sensitive component 24; the first sensitive component 21 and the second sensitive component 22 are arranged in the area of the little finger, and the third sensitive component 23 and the fourth sensitive component 24 are arranged in the palm area adjacent to the little finger.

[0046] The second sensitive module includes a fifth sensitive component 25, a sixth sensitive component 26, a seventh sensitive component 27, an eighth sensitive component 28, and a ninth sensitive component 29; the fifth sensitive component 25, the sixth sensitive component 26, and the seventh sensitive component 27 are arranged in the area of the ring finger, and the eighth sensitive component 28 and the ninth sensitive component 29 are arranged in the palm area adjacent to the ring finger.

[0047] The third sensitive module includes a tenth sensitive component 210, an eleventh sensitive component 211, a twelfth sensitive component 212, and a thirteenth sensitive component 213; the tenth sensitive component 210, the eleventh sensitive component 211, and the twelfth sensitive component 212 are arranged in the area of the middle finger, and the twelfth sensitive component 212 and the thirteenth sensitive component 213 are arranged in the palm area adjacent to the middle finger.

[0048] The fourth sensitive module comprises a fourteenth sensitive component 214, a fifteenth sensitive component 215 and a sixteenth sensitive component 216; the fourteenth sensitive component 214 and the fifteenth sensitive component 215 are arranged in the region where the index finger is located, and the sixteenth sensitive component 216 is arranged in the palm region adjacent to the index finger.

[0049] The fifth sensitive module comprises a seventeenth sensitive component 217, an eighteenth sensitive component 218 and a nineteenth sensitive component 219; wherein the eighteenth sensitive component 218 and the nineteenth sensitive component 219 are arranged in the region where the thumb is located, and the seventeenth sensitive component 217 is arranged in the palm region adjacent to the thumb.

[0050] In combination with FIGS. 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 and 12, Figure 3 , Figure 6 and Figure 7 , a is the left electrode wire of the first sensitive component 21;

[0051] b is the left electrode wire of the second sensitive component 22;

[0052] c is the left electrode wire of the third sensitive component 23;

[0053] d is the left electrode wire of the fourth sensitive component 24;

[0054] e is the right electrode wire of the first sensitive component 21, the second sensitive component 22, the third sensitive component 23 and the fourth sensitive component 24 combined to form a common wire;

[0055] f is the left electrode wire of the fifth sensitive component 25;

[0056] g is the left electrode wire of the sixth sensitive component 26;

[0057] h is the left electrode wire of the seventh sensitive component 27;

[0058] i is the left electrode wire of the eighth sensitive component 28;

[0059] k is the left electrode wire of the ninth sensitive component 29;

[0060] j is the right electrode wire of the fifth sensitive component 25, the sixth sensitive component 26, the seventh sensitive component 27, the eighth sensitive component 28 and the ninth sensitive component 29 combined to form a common wire;

[0061] l is the left electrode wire of the tenth sensitive component 210;

[0062] m is the left electrode wire of the eleventh sensitive component 211;

[0063] n is the left electrode wire of the twelfth sensitive component 212;

[0064] p is the left electrode trace of the thirteenth sensitive component 213;

[0065] o is the common trace formed by the right electrode traces of the tenth sensitive component 210, the eleventh sensitive component 211, the twelfth sensitive component 212 and the thirteenth sensitive component 213;

[0066] q is the left electrode trace of the fourteenth sensitive component 214;

[0067] r is the left electrode trace of the fifteenth sensitive component 215;

[0068] t is the left electrode trace of the sixteenth sensitive component 216;

[0069] u is the right electrode trace of the seventeenth sensitive component 217;

[0070] v is the right electrode trace of the eighteenth sensitive component 218;

[0071] w is the right electrode trace of the nineteenth sensitive component 219;

[0072] s is the common trace formed by the right electrode traces of the fourteenth sensitive component 214, the fifteenth sensitive component 215 and the sixteenth sensitive component 216, and the left electrode traces of the seventeenth sensitive component 217, the eighteenth sensitive component 218 and the nineteenth sensitive component 219;

[0073] Therefore, through the novel design layout of the sensitive module, the pressure sensor of the utility model can realize full-hand coverage of the robot hand; the sensing unit is reasonably distributed in the finger joints and the palm key stress area, and cooperates with the modular lead design, so that the hand can realize real-time sensing of the pressure size when gripping under the premise of ensuring signal integrity, thereby solving the problem of lack of force sense information of the other parts of the fingers except the finger tips and the palm parts, not only improving the overall sensing ability of the robot hand, but also making it have more accurate force feedback in complex operation, thereby significantly improving the interactive safety and operation stability.

[0074] As a preferred embodiment, in each of the sensitive components, the substrate 10 is a PI substrate, that is, a film or sheet made of polyimide as the core material; the lower electrode 11 is formed on the substrate 10 by a graphic printing process;

[0075] The surface of the lower electrode 11 closely adheres to the composite sensitive layer 12.

[0076] Specifically, the wrinkled structure of the composite sensitive layer 12 utilizes the high aspect ratio and strong van der Waals forces inherent in multi-walled carbon nanotubes (MWCNTs), resulting in their spontaneous aggregation in polydimethylsiloxane (PDMS).

[0077] The outermost layer is a polydimethylsiloxane (PDMS) film as the encapsulation layer 14 for conformal encapsulation, which is both waterproof and oxygen-resistant and ensures stretchability; the upper electrode 13 is printed on the inner surface of the encapsulation layer 14.

[0078] According to the capacitance formula C = ε·S / d, when an external force is applied to the hand, the composite sensitive layer 12 is divided into two functional sub-segments: a "wrinkled layer" and a "film layer," which correspond to... Figure 5 In the equivalent circuit of the pressure sensor of this invention, the overlapping area S of the electrodes is a fixed constant, so the capacitance is mainly determined by the dielectric constant ε and the distance d between the two electrodes.

[0079] The composite sensitive layer 12 includes a wrinkled layer and a film layer. The wrinkled layer includes a first capacitor C1 and a second capacitor C2 connected in parallel. The film layer includes a third capacitor C3. The wrinkled layer is connected to the film layer, and the film layer is disposed on both sides of the wrinkled layer.

[0080] exist Figure 5 In the initial state shown in Figure i, no external force is applied, a large amount of air is sealed inside the wrinkled layer, the overall dielectric constant ε is at a low level, and the capacitance remains at its initial value.

[0081] Enter Figure 5 During the low-pressure stage shown in Figure ii, the top of the wrinkles collapses first, the air is quickly squeezed out, and the electrode spacing d decreases sharply. At the same time, the highly conductive multi-walled carbon nanotube (MWCNT) network causes ε to rise synchronously due to volume compression. C1 and C2 become the dominant outputs, determining the signal output from the electrodes to the external circuit.

[0082] As the pressure continues to increase to Figure 5 In the high-pressure stage shown in diagram iii, the wrinkled layer is completely flattened, air is almost expelled, and ε approaches saturation. At this point, the elastic deformation of the film layer begins to contribute significantly, and C3 takes over, its capacitance determining the overall sensor response. The capacitance change remains linearly related to pressure. Thanks to the "wrinkled-high dielectric" synergistic mechanism, the sensor maintains high sensitivity and linearity throughout the entire range, providing reliable tactile feedback for a precise hand grip experience.

[0083] Specifically, in the low pressure stage, the dielectric constant change is dominated by the wrinkle collapse, and the sensitivity reaches 19.4 kPa-1; in the medium pressure stage, the dielectric constant gradient is improved by the compression of the multi-walled carbon nanotube (MWCNT) network; in the high pressure stage, the elastic deformation of the film layer maintains stable linearity and sensitivity. The three-stage response mechanism makes the sensor maintain a linear relationship between the capacitance size and the pressure in the full range of 0-21 kPa, so that the sensitivity and linearity remain stable as the pressure increases, which is a great improvement over traditional capacitive sensors, ensuring that the dexterous hand can obtain accurate tactile feedback under different pressure conditions, significantly improving the reliability and adaptability of grip control.

[0084] The first capacitor C1 is a capacitor with a vacuum dielectric layer;

[0085] The second capacitor C2 is a capacitor with a wrinkled multi-walled carbon nanotube / polydimethylsiloxane (MWCNT / PDMS) composite film dielectric layer;

[0086] The third capacitor C3 is a capacitor with a planar multi-walled carbon nanotube / polydimethylsiloxane (MWCNT / PDMS) composite film dielectric layer.

[0087] From a process point of view, the packaging layer 14 and the upper electrode 13, the composite sensitive layer 12, the lower electrode 11, and the substrate 10 are packaged by a low-temperature compression packaging process.

[0088] As a preferred embodiment, in combination with Figure 4 As shown, the lower electrode 11 is designed as a circle, and the composite sensitive layer 12 is designed as a square. It should be noted that the above shape design is only one embodiment of the present application, and in some other embodiments, the shape of the composite sensitive layer 12 can also be designed as a circle or other shapes. When the composite sensitive layer 12 is set as a circle, the composite sensitive layer 12 and the lower electrode 11 are concentrically arranged, and the diameter of the lower electrode 11 is smaller than the diameter of the composite sensitive layer 12. The concentric electrode structure can realize seamless integration of the sensitive component and the lead unit, simplify the manufacturing process, not only reduce the production cost, but also reduce the interference of the sensor to the flexibility of the hand, making it suitable for precise operation in high dynamic scenes.

[0089] As a preferred embodiment, the upper electrode 13 is an ITO / PET film, and the packaging layer 14 is a polydimethylsiloxane film.

[0090] It should be noted that ITO / PET is a kind of composite flexible transparent conductive film, which is combined by two materials with completely different properties through a process, wherein PET (polyethylene terephthalate) is a base layer, which provides flexible physical support; ITO (indium tin oxide) is a coating layer, which provides key conductive and optical functions.

[0091] The utility model discloses a single layer whole surface circular electrode as the lower electrode layer of capacitive flexible tactile sensor, and the electrode is directly formed on the flexible PCB through silk screen printing, and the whole is disc -shaped, and is concentrically attached with the circular profile of the sensitive unit. The whole electrode surface is continuous without break, and is extended to the combined bus of wrist part through flexible lead, and the number of wiring is significantly reduced. The circular electrode is closely attached with the overlying high dielectric composite layer. When the hand is subjected to external force, the thickness and dielectric constant of the composite layer change synchronously, the electrode-composite layer electric field strength is uniformly adjusted as a whole, so that the pressure information is converted into the capacitive signal with good linearity, and is output in real time to the subsequent model through the combined lead for analysis.

[0092] The embodiment two of the utility model discloses a kind of robots, including robot body, execution component and the pressure sensor as described in embodiment one, the pressure sensor is installed in the execution component.

[0093] The embodiment three of the utility model discloses a preparation method for preparing the pressure sensor as described in embodiment one,

[0094] The pressure sensor is a capacitive flexible tactile sensor for robot dexterous hand, and the whole is ultra-thin flexible patch structure. The sensing unit includes a flexible packaging layer 14, a composite sensing layer 12 and an electrode layer. The electrode layer includes an upper electrode 13 and a lower electrode 11.

[0095] The graphical printing process and the modular preparation process are used in the preparation process, which can effectively reduce the production cost and improve the consistency of the sensing unit.

[0096] Specifically, the sensing unit array takes a circular sensitive component as a basic unit, which is reasonably distributed according to the dexterous hand skeleton structure to realize seamless perception in the whole domain. The sensitive component includes a circular lower electrode 11. The circular electrode layer is prepared by a printing process, and a composite sensing layer 12 (dielectric layer) with a corrugated structure is overlaid on the electrode layer. The composite sensing layer 12 takes a multi-walled carbon nanotube / polydimethylsiloxane (MWCNT / PDMS) composite film as a matrix. By adjusting the mass fraction of multi-walled carbon nanotubes MWCNT and the spin-coating-vacuum-curing process, a random corrugated structure is spontaneously formed on the surface of the film. The corrugations collapse step by step when pressed, and the composite matrix with high dielectric constant is used to realize the synchronous maintenance of sensitivity and linearity in the range of 0-21 kPa.

[0097] The composite sensitive layer 12 is above the ITO / PET upper electrode 13, which corresponds to the circular lower electrode 11, to realize the sensing principle of the capacitive sensor. The outermost layer is the encapsulation layer 14, which is a polydimethylsiloxane (PDMS) film. After plasma treatment, the lower layer structure is low-temperature compression bonded to ensure water and oxygen barrier and biocompatibility, while allowing more than 30% tensile deformation without affecting performance.

[0098] The preparation method comprises:

[0099] First, the substrate is pretreated. A 25 μm thick double-sided copper-coated polyimide (PI-Cu) roll material is selected, laser-cut into a palm profile, and then sequentially subjected to plasma cleaning, micro-etching, and drying to remove surface impurities and increase roughness, thereby improving the subsequent printing adhesion.

[0100] The pretreated PI-Cu roll material is placed in a screen printing machine, and a silver-epoxy composite conductive paste is used to print a circular electrode array through a 300-mesh stainless steel screen in one pass. After printing, the material is pre-baked at 80°C for 10 minutes and then cured at 150°C for 30 minutes to form a conductive circuit with a thickness of about 18 μm.

[0101] Multi-walled carbon nanotubes (MWCNTs) are ultrasonically dispersed in n-hexane at a ratio of 2.6 wt%, and then PDMS prepolymer and curing agent (mass ratio 10:1) are added and magnetically stirred for 10 minutes to obtain a uniform slurry. The slurry is spin-coated on a clean glass substrate (250 rpm, 20 s), vacuum degassed for 5 minutes, and then placed in a 90°C oven for 1 hour and naturally cooled to obtain a composite film with a thickness of about 160 μm. The stress mismatch induced by the aggregation of multi-walled carbon nanotubes (MWCNTs) spontaneously forms random wrinkles on the surface of the film without the need for additional templates or etching. The resulting wrinkled dielectric film is laser-cut into 3 mm diameter discs, which are precisely attached to the electrode array using a transfer process, and low-temperature compression bonding ensures no air bubbles or misalignment.

[0102] The upper electrode is then printed on the surface of a polydimethylsiloxane (PDMS) film, which is then covered on the sensitive unit array after oxygen plasma treatment. Vacuum lamination at 80°C for 30 minutes completes the production of the encapsulation layer.

[0103] Finally, the combined bus is connected to the external FPC (Flexible Printed Circuit) ribbon cable at the wrist outlet using flexible conductive glue, and the entire waterproof coating is processed to obtain the finished sensor.

[0104] In the description of the utility model, need understanding is, the term "first", "second" only for the purpose of description, and can not be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Therefore, the features limited by "first", "second" can explicitly or implicitly include one or more features. In the description of the utility model, the meaning of "a plurality of" is two or more than two, unless otherwise specifically limited.

[0105] In the utility model, unless otherwise specifically defined and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood broadly, for example, can be fixedly connected, can also be detachably connected, or integrated; can be mechanically connected, can also be electrically connected; can be directly connected, can also be indirectly connected through an intermediate medium; can be the communication between two elements or the interaction relationship between two elements. For ordinary skilled in the art, the specific meaning of the above terms in the utility model can be understood according to the specific circumstances.

[0106] Obviously, the above embodiments are only examples for clearly illustrating, and are not limited to the embodiments. For ordinary skilled in the art, other different forms of changes or variations can be made on the basis of the above description. Here, all the embodiments need not and cannot be exhausted. The obvious changes or variations derived therefrom are still within the protection scope of the utility model.

Claims

1. A pressure sensor characterized by: An execution component applied to a robot, the execution component comprising a base body, a projection of the base body along a thickness direction being identical to a shape of a hand, the base body having a palm region, a finger region and a wrist region, the pressure sensor comprising, a sensing unit comprising a plurality of sensitive modules arranged on the palm region and the finger region; each of the sensitive modules comprising a plurality of sensitive components, each of the sensitive components comprising, in sequence along the thickness direction, a substrate, a lower electrode, a composite sensitive layer, an upper electrode and an encapsulation layer; the composite sensitive layer comprising a corrugated layer and a film layer, the corrugated layer and the film layer being adhered to each other to form a corrugated structure; a lead unit connected to the sensing unit to output sensing signals of the sensing unit; the lead unit comprising upper electrode leads, lower electrode leads, a common lead and a total output terminal; each of the upper electrodes being connected to the total output terminal through the upper electrode leads, each of the lower electrodes being connected to the common lead through the lower electrode leads, and a terminal end of the common lead being connected to the total output terminal; the total output terminal being arranged at the wrist region; in the same sensitive module, the upper electrode leads being connected to one side of the sensitive components, and the lower electrode leads and the common lead being connected to the other side of the sensitive components; a control unit connected to the sensing unit through the lead unit, the control unit receiving the sensing signals, converting the sensing signals into pressure signals after data processing and outputting the pressure signals.

2. A pressure sensor according to claim 1, wherein: the sensing unit comprising a first sensitive module, a second sensitive module, a third sensitive module, a fourth sensitive module and a fifth sensitive module; the first sensitive module being located at a region of a little finger on the base body and the palm region; the second sensitive module being located at a region of a ring finger on the base body and the palm region; the third sensitive module being located at a region of a middle finger on the base body and the palm region; the fourth sensitive module being located at a region of an index finger on the base body and the palm region; and the fifth sensitive module being located at a region of a thumb on the base body and the palm region.

3. A pressure sensor according to claim 2, wherein: the first sensitive module comprising a first sensitive component, a second sensitive component, a third sensitive component and a fourth sensitive component; the second sensitive module comprising a fifth sensitive component, a sixth sensitive component, a seventh sensitive component, an eighth sensitive component and a ninth sensitive component; the third sensitive module comprising a tenth sensitive component, an eleventh sensitive component, a twelfth sensitive component and a thirteenth sensitive component; the fourth sensitive module comprising a fourteenth sensitive component, a fifteenth sensitive component and a sixteenth sensitive component; the fifth sensitive module comprising a seventeenth sensitive component, an eighteenth sensitive component and a nineteenth sensitive component.

4. The pressure sensor of claim 1, wherein: the lower electrode being formed on the substrate by graphic printing; the composite sensitive layer being arranged on the lower electrode, one side of the upper electrode being adhered to the composite sensitive layer, and the other side of the upper electrode being adhered to the encapsulation layer.

5. The pressure sensor of claim 1, wherein: the encapsulation layer being encapsulated with the upper electrode, the composite sensitive layer, the lower electrode and the substrate by low-temperature compression.

6. The pressure sensor of claim 1, wherein: The lower electrode and the composite sensitive layer are circular, the composite sensitive layer is concentrically arranged with the lower electrode, and the diameter of the lower electrode is smaller than that of the composite sensitive layer.

7. A pressure sensor according to any one of claims 1 to 6, wherein: The wrinkle layer comprises a first capacitor C1 and a second capacitor C2; the film layer comprises a third capacitor C3; the first capacitor C1 and the second capacitor C2 are connected in parallel, and then connected in series with the third capacitor C3.

8. A pressure sensor according to claim 7, wherein: The first capacitor C1 is a capacitor with a vacuum dielectric layer, the second capacitor C2 is a capacitor with a wrinkled multi-walled carbon nanotube / polydimethylsiloxane composite film dielectric layer, and the third capacitor C3 is a capacitor with a planar multi-walled carbon nanotube / polydimethylsiloxane composite film dielectric layer.

9. The pressure sensor of claim 1, wherein: The upper electrode is an ITO / PET film, and the packaging layer is a polydimethylsiloxane film.

10. A robot, characterized by: The robot comprises a robot body, an execution component, and a pressure sensor as claimed in any one of claims 1-9, wherein the pressure sensor is mounted on the execution component.

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