A sensor cleaning device and method based on micro-nano ultrasonic robot

Abstract

The present invention discloses a sensor cleaning device and method based on a micro-nano ultrasonic robot. The device comprises a vibration transmission platform and a micro-nano ultrasonic robot. The vibration transmission platform comprises a substrate and a piezoelectric ceramic transducer attached to the lower surface of the substrate. The micro-nano ultrasonic robot comprises a housing and bubbles within the housing. The micro-nano ultrasonic robot is dispersed in a liquid medium. The piezoelectric ceramic transducer is used to generate mechanical vibrations that resonate the vibration transmission platform, thereby generating an ultrasonic field in the liquid medium. The bubbles are forced to vibrate in the ultrasonic field and undergo periodic expansion-contraction cycles, generating a locally enhanced acoustic flow field on the bubble surface and in the surrounding liquid to clean the sensor. The present invention utilizes the micro-nano ultrasonic robot containing bubbles to remove biofouling from the sensor electrode surface. This allows for the regeneration of electrode activity after detection, enabling the sweat sensor to be reused multiple times. This contributes to the development and application of wearable continuous sweat detection devices.

Description

Technical Field

[0001] The present invention relates to the fields of electrochemical sensors, micro-nano robots, and ultrasonic manipulation, and in particular to a sensor cleaning device and method based on a micro-nano ultrasonic robot. Background Art

[0002] Electrochemical biosensing is an important analytical and detection technology widely used in medical diagnosis, environmental monitoring, food safety, and other fields. Based on the principles of electrochemical analysis, this technology uses biological fluid samples such as blood, sweat, urine, saliva, and interstitial fluid as detection targets. The sensor generates a corresponding electrical signal when identifying cells or biomolecules in the sample, enabling highly sensitive detection of trace targets with excellent selectivity. Sweat contains electrolytes, metabolites, amino acids, proteins, hormones, and other markers of human health, comparable to blood, making it an ideal diagnostic biofluid for non-invasive electrochemical biosensors. However, during the sweat collection process, lipids, proteins, and shed cortical tissue from the body's surface can easily form biofouling on the sensor surface, causing a rapid decrease in sweat sensitivity. The lack of technologies to clean contaminants from the surface of sweat sensor electrodes has severely hampered the use and widespread adoption of this technology.

[0003] In the prior art, Chinese Invention Patent Publication No. CN112903766A describes a capillary flow-guided micro-sweat sensor structure and micro-sweat sensor. These sensors utilize sweat for non-invasive detection. These sensors incorporate capillary channels for sweat drainage, integrated with detection electrodes and a circuit board. While the complex microstructure facilitates sweat collection and detection, it also increases the likelihood of sample flow line blockage and dirt accumulation on the electrode surfaces, limiting their application in wearable devices and continuous sweat detection. Chinese Invention Patent Publication No. CN113640357A describes a wearable sweat sensor device for real-time and continuous electrolyte concentration detection. The device comprises a sweat channel, a detection mechanism, and a sweat absorption mechanism. This device enables real-time and continuous detection of sweat electrolyte concentration, with the results unaffected by the mixing of fresh and old sweat. However, this design fails to address the potential for sensor signal drift caused by the accumulation of sebum, dandruff, and other substances in sweat on the electrodes during prolonged testing. Chinese Invention Patent Publication No. CN111474222A describes a regenerative electrochemical sensor for the simultaneous detection of epinephrine and uric acid, its preparation method, and its application. The designed P-TP / rGO / GCE-modified electrode effectively catalyzes the electrooxidation of epinephrine and uric acid and uses electrochemical reduction to remove contaminants from the electrochemical sensor surface, achieving regeneration and self-cleaning effects. Chinese Invention Patent Publication No. CN109661571A describes a system and method for identifying and cleaning contamination in electrochemical sensors, using cyclic voltammetry for scanning cleaning of electrochemical sensors. Electrode cleaning using electrochemical redox reactions is effective for removing specific and nonspecific ion adsorption on the electrode surface. However, during the use of sweat sensors, the contamination layer on the electrode surface contains not only various inorganic salts but also proteins, sloughed skin, and other contaminants that cannot be directly removed using electrochemical methods. Conventional physical cleaning methods such as ultrasonic cleaning, wiping, and polishing can easily damage the electrocatalyst-modified layer on the surface of the electrochemical biosensor, causing irreversible damage to sensor performance. Therefore, there is an urgent need for a gentle sweat sensor cleaning method that can remove the contamination layer on the sensor electrode surface while reducing damage and destruction to the electrocatalyst modification layer.

[0004] Micro-nano robots, also known as micro-nanomotors, are a class of micro-nano-sized functional materials capable of self-propulsion or controlled motion under the influence of external physical fields in specific fuel environments, providing a new solution to the aforementioned problems. Micro-nano robots driven by ultrasonic fields are also referred to as micro-nano ultrasonic robots. Chinese Invention Patent Publication No. CN114193428A describes a bubble-propelled micro-nano ultrasonic robot, its preparation method, and its driving method. These utilize the principle of ultrasonically stimulated bubble resonance to enable the micro-nano ultrasonic robot to perform long-range motion in a flow field to capture dispersed target substances. The micro-nano ultrasonic robot, carrying stable bubbles, is released into an ultrasonic field. Without involving a chemical reaction, the bubbles within the micro-nano ultrasonic robot resonate at a certain characteristic frequency, propelling the robot to move and capture the dispersed target substances. Chinese Invention Patent Publication No. CN113418971A describes an electrochemical sensor based on a micro-nano ultrasonic robot. The proposed micro-nano ultrasonic robot can capture dispersed target substances in a liquid sample, which are then concentrated on the surface of an electrochemical sensing electrode, causing a change in the electrical signal, thereby achieving ultrasensitive detection of the target substance in the liquid medium. The application of micro-nano ultrasonic robots in electrochemical biosensors will help to clean the biological fouling layer on the electrode surface and regenerate the detection performance of sweat sensors. Summary of the Invention

[0005] Purpose of the invention: In view of the above shortcomings, the present invention provides a sensor cleaning device and method based on a micro-nano ultrasonic robot.

[0006] Technical solution: To solve the above problems, the present invention adopts a sensor cleaning device based on a micro-nano ultrasonic robot, including a vibration transmission platform and a micro-nano ultrasonic robot. The vibration transmission platform includes a substrate and a piezoelectric ceramic transducer adhered to the lower surface of the substrate. The micro-nano ultrasonic robot includes a shell and bubbles located in the shell. The micro-nano ultrasonic robot is dispersed in a liquid medium; the piezoelectric ceramic transducer is used to generate mechanical vibrations and resonate the vibration transmission platform, thereby generating an ultrasonic field in the liquid medium. The bubbles are forced to vibrate in the ultrasonic field and undergo periodic expansion-contraction cycles. A locally enhanced acoustic flow field is generated on the bubble surface and in the nearby liquid to clean the sensor.

[0007] Furthermore, the shell contains a catalyst, the liquid medium contains a catalytic substrate, and the catalyst decomposes the catalytic substrate to generate bubbles.

[0008] Furthermore, the shell is a polymer film, and the bubbles are wrapped in the polymer film.

[0009] Furthermore, a plurality of mutually unconnected cavities are provided in the shell, the inner walls of the cavities are made of a hydrophobic material, and bubbles are generated in the cavities when the shell is dispersed in a liquid medium.

[0010] Furthermore, the shell is a multilayer tube, including a poly (3,4-ethylenedioxythiophene) (PEDOT) support layer, a SiO2 inner layer and a hydrophobic inner surface layer arranged layer by layer from the outside to the inside, and bubbles are generated inside the shell when it is dispersed in a liquid medium.

[0011] Furthermore, the shell is made of mesoporous material, and the shell is modified with biological enzymes or different types of drugs to remove pollutants with specific components on the surface of the electrode, and multiple bubbles attract and merge with each other to enhance the cleaning ability.

[0012] Furthermore, it also includes a sensor, which is a planar electrochemical biosensor, including a counter electrode, a working electrode, and a reference electrode.

[0013] Furthermore, the substrate is a quartz glass substrate.

[0014] The present invention also provides a cleaning method for the sensor cleaning device, which is characterized in that the sensor to be cleaned is placed on a vibration transmission platform, and a liquid medium in which a micro-nano ultrasonic robot is dispersed is dripped onto the surface of the sensor to be cleaned, so that the piezoelectric ceramic transducer generates mechanical vibration, and the vibration is transmitted to the liquid medium through the vibration transmission platform and the sensor to be cleaned, and the micro-nano ultrasonic robot in the liquid medium cleans the surface of the sensor to be cleaned.

[0015] Furthermore, a liquid reservoir is provided between the surface to be cleaned of the sensor to be cleaned and the vibration transmission platform, and the liquid medium in which the micro-nano ultrasonic robots are dispersed is filled in the liquid reservoir.

[0016] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages: (1) the micro-nano ultrasonic robot containing bubbles is used to remove biological fouling on the sensor electrode surface, and the electrode activity can be regenerated after detection, so that the sweat sensor can be reused many times, which is conducive to the development and application of wearable continuous sweat detection equipment; (2) the micro-nano ultrasonic robot is only in the nanometer to micrometer size and has a fast movement speed. It can be easily integrated into the electrochemical biosensor device with small size and diverse structure to clean the surface of the sensitive element in the sensor; (3) the micro-nano ultrasonic robot can clean in an independent or cluster collaborative manner without damaging the sensor surface, and the cluster collaborative method enhances the cleaning ability of the dirt layer on the electrode surface; (4) the acoustic flow generated by physical means is used to clean the sensor surface. , which can remove pollutants such as large molecular proteins and dandruff that cannot be removed by electrochemical redox methods; (5) The shell of the micro-nano ultrasonic robot can be made of mesoporous materials to provide a larger specific surface area, which can be further modified with drugs such as proteases and lipases, and promote the decomposition of specific substances such as proteins and lipids on the surface of the sweat sensor electrode by chemical reactions, thereby enhancing the cleaning ability of the dirt layer on the electrode surface; (6) Compared with the traditional cleaning method of using running water or ultrasonic cleaning, the cleaning method using the micro-nano ultrasonic robot can accurately control the cleaning position and acoustic flow intensity of the micro-nano ultrasonic robot by adjusting the frequency and voltage of the ultrasonic excitation. The cleaning force and controllability are higher, and it is not easy to damage the electrocatalyst modification layer on the sensor surface, which helps to maintain the long-term or repeated use of the sweat sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Schematic diagram of the overall structure of the sensor cleaning device of the present invention;

[0018] Figure 2 This is an exploded view of the vibration transmission platform and sweat sensor structure of the present invention;

[0019] Figure 3 This is a schematic structural diagram of the micro-nano ultrasonic robot configuration 1 of the present invention;

[0020] Figure 4 This is a schematic structural diagram of the second configuration of the micro-nano ultrasonic robot of the present invention;

[0021] Figure 5 Schematic diagram of the structure of the micro-nano ultrasonic robot configuration three of the present invention;

[0022] Figure 6 Schematic diagram of the structure of the micro-nano ultrasonic robot configuration four of the present invention;

[0023] Figure 7 This is a schematic diagram of the second placement method of the vibration transmission platform and sweat sensor;

[0024] Figure 8This is a schematic diagram of the micro-nano ultrasonic robot cleaning electrode of the present invention;

[0025] Figure 9 This is the simulation result of the acoustic flow field generated by the bubble vibration of the micro-nano ultrasonic robot of the present invention;

[0026] Figure 10 This is a schematic diagram of the micro-nano ultrasonic robot configuration forming a cluster;

[0027] Figure 11 This is a schematic diagram of a cluster formed by the second configuration of the micro-nano ultrasonic robot of the present invention;

[0028] Figure 12 This is a schematic diagram of the electrode contamination-cleaning process;

[0029] Figure 13 Schematic diagram of the signal changes of the sweat sensor using cyclic voltammetry before and after cleaning;

[0030] Figure 14 It is the IT curve of measuring different concentrations of standard reagents using chronoamperometry;

[0031] Figure 15 The corresponding relationship between the sensor electrical signal and the concentration of the analyte when using the chronoamperometry method;

[0032] Figure 16 Schematic diagram of the signal changes of the sweat sensor using chronoamperometry before and after cleaning;

[0033] In the figure, 1 is the insulating coating; 2 is the quartz glass substrate of the vibration transmission platform; 3 is the piezoelectric ceramic transducer; 4 is the counter electrode; 5 is the working electrode; 6 is the reference electrode; 7 is the sweat sensor base; 8 is the shell of the micro-nano ultrasonic robot; 9 is the bubble of the micro-nano ultrasonic robot; and 10 is the liquid reservoir. DETAILED DESCRIPTION

[0034] like Figure 1 and Figure 2 As shown in the figure, a sensor cleaning device based on a micro-nano ultrasonic robot in this embodiment includes a vibration transmission platform, a sweat sensor, and a micro-nano ultrasonic robot for cleaning the sensor electrodes. The vibration transmission platform includes a quartz glass substrate 2 and a piezoelectric ceramic transducer 3. The quartz glass substrate 2 measures 25×15×0.5 mm. The piezoelectric ceramic transducer 3 is a ring-shaped lead zirconate titanate piezoelectric ceramic with dimensions of φ20×φ10×1 mm. The piezoelectric ceramic transducer 3 is attached to the lower surface of the quartz glass substrate 2 using epoxy resin glue to form the vibration transmission platform.

[0035] The sweat sensor is a planar three-electrode electrochemical biosensor comprising a substrate 7, a counter electrode 4, a working electrode 5, a reference electrode 6, and an insulating layer 1. The counter electrode 4, working electrode 5, and reference electrode 6 of the sweat sensor are screen-printed onto the surface of the substrate 7. First, conductive ink containing silver nanoparticles is used to create the three electrodes. Carbon paste is then used to cover the portions of the counter electrode 4 and working electrode 5 exposed within the circular holes of the insulating layer 1. Finally, insulating ink is used to print the insulating layer 1. Each layer is printed using a corresponding patterned printing stencil. The ink is squeezed through the holes in the stencil onto the surface of the substrate 7, forming the corresponding pattern. The ink is then cured by baking at 90°C for 30 minutes. The working electrode is surface-modified with an enzyme or non-enzymatic electrocatalyst, enabling it to detect specific substances in human sweat. In the sweat glucose sensor, cuprous oxide is used as the electrocatalyst to modify the working electrode. Disperse 2 mg of cuprous oxide powder in 1 ml of N,N-dimethylformamide (DMF) solution, drop it onto the surface of the working electrode several times and dry it, and finally cover it with a small amount of chitosan to protect the electrode.

[0036] Micro-nano ultrasonic robots can adopt the following four basic configurations: Figure 3 As shown, the shell 8 of the micro-nano ultrasonic robot contains a catalyst, and the liquid medium contains a catalytic substrate. The catalyst decomposes the catalytic substrate and generates bubbles 9. Figure 4 As shown, the shell 8 of the micro-nano ultrasonic robot is a polymer film, and the bubble 9 is wrapped in the polymer film. Figure 5 As shown, the shell 8 of the micro-nano ultrasonic robot is made by two-photon 3D printing technology. There are two or more cavities that are not connected to each other in the shell 8. The inner wall of the cavity is made of hydrophobic material. Due to the hydrophobic properties of the inner wall, bubbles 9 are naturally generated in the cavity when the shell 8 is dispersed in the liquid medium. Figure 6 As shown, the shell 8 of the micro-nano ultrasonic robot is a multilayer tube with a diameter of 5 μm and a length of 10-15 μm, including a poly (3,4-ethylenedioxythiophene) (PEDOT) support layer, a SiO2 inner layer and a hydrophobic inner surface layer several nanometers thick. The shell 8 of this configuration is prepared by a template-assisted electrochemical deposition method, and the chemicals used include 3,4-ethylenedioxythiophene (EDOT), sodium dodecyl sulfate (SDS), KNO3, hexadecyltrimethylammonium bromide (CTAB), (3-aminopropyl) triethoxysilane (APTES), anhydrous ethanol, and (hexafluoro-1,1,2,2-tetradecyl) trimethoxysilane (AC-FAS). The electrochemical deposition parameters are set by a CHI660E electrochemical workstation. A three-electrode system is used for deposition, with a 12 cm 2A stainless steel sheet served as the counter electrode, Ag / AgCl (3M KCl) as the reference electrode, and a gold layer approximately 70 nm thick was sputtered on one side of the PC film as the working electrode. All electrochemical deposition steps were performed at room temperature (20°C). First, an outer PEDOT layer was deposited using a solution containing 7.5 mM KNO₃, 15 mM EDOT, and 100 mM SDS at a potential of +1 V and a charge of 0.1 C. Subsequently, a SiO₂ layer was deposited using a mixed solution of CTAB (5 mM), APTES (25 mM), and anhydrous ethanol (7.5 M) at a potential of -1 V and a charge of 0.2 C. The electrochemical synthesis of SiO₂ involves two steps: the first involves the hydrolysis of APTES under electrical conditions and CTAB solution, removing the three ethyl groups. However, the propylamine is difficult to hydrolyze, leaving silanol residues. The second step involves a dehydration condensation reaction of the silanols, ultimately forming an organic silica network. A large number of hydroxyl and amino groups that did not participate in the reaction provided the basis for further hydrophobic treatment of the inner surface of the shell 8. After the electrochemical deposition was completed, the gold layer on the PC film was polished and removed by Al2O3 suspension. Under a constant pressure of 0.08MPa, the AC-FAS solution was vacuum-pumped within 5 minutes to complete the hydrophobic modification of the inner surface of the shell 8. The PC film was then dissolved with dichloromethane, and the micro-nano ultrasonic robot shell 8 was removed from the PC film by centrifugation at 8000rpm for 3 minutes. Finally, it was washed 3 times with dichloromethane, ethanol and deionized water. Since the inner surface of the shell 8 is hydrophobic, bubbles 9 are naturally generated inside the micro-nano ultrasonic robot when it is dispersed in water.

[0037] The cleaning method of the sensor cleaning device of the present invention is as follows: first, the sweat sensor to be cleaned is placed on the vibration transmission platform. Two placement methods can be used: (1) the base 7 is adhered to the upper surface of the quartz glass substrate 2 using epoxy resin glue, and then the liquid medium dispersed with the micro-nano ultrasonic robot is dripped onto the surface of the sensor to be cleaned; (2) Figure 7 As shown, the upper surface of the quartz glass substrate 2 is opposite to the surface to be cleaned of the sweat sensor, with a liquid reservoir 10 sandwiched in between. The liquid reservoir 10 uses acrylic material, and its inner diameter size matches the inner hole size of the insulating layer 1. The micro-nano ultrasonic robot is dispersed in the aqueous solution in the liquid reservoir. After fixing the sweat sensor, a signal generator is used to generate an ultrasonic frequency sinusoidal AC signal. In this embodiment, the resonance frequency of the vibration transmission platform is 48kHz. The electrical signal is amplified to 10Vpp by a power amplifier and then applied to the piezoelectric ceramic transducer 3. Due to the inverse piezoelectric effect, the piezoelectric ceramic transducer 3 vibrates mechanically and excites the resonance of the vibration transmission platform. As shown Figure 8As shown, the vibration is transmitted to the liquid on the electrode surface through the quartz glass substrate 2 and the sweat sensor base 7, generating an ultrasonic field in the liquid. The bubbles 9 contained in the micro-nano ultrasonic robot in the liquid will be forced to vibrate in the acoustic field, undergoing a periodic expansion-contraction cycle, and generating a locally enhanced acoustic flow field in the liquid near the surface of the bubble 9, as shown in FIG. Figure 9 As shown, the sensor electrode can be cleaned. In addition, due to the secondary Bjerknes force, the vibrating bubbles 9 are adsorbed to the electrode surface, and multiple micro-nano ultrasonic robots will attract each other to form a cluster, and multiple bubbles 9 may merge with each other, as shown in FIG. Figure 10 and Figure 11 This phenomenon further enhances the acoustic flow generated by the micro-nano ultrasonic robot and its ability to clean contaminants from the sensor electrode surface. The outer shell can also be made of mesoporous materials to provide a larger comparative surface area. To target specific contaminants, the micro-nano ultrasonic robot shell can be modified with enzymes or different types of drugs to remove specific components of contaminants from the electrode surface. In addition to sweat sensors, other types of electrochemical sensors can also be cleaned using this method.

[0038] The micro-nano ultrasonic robot of the present invention has the following effect on removing pollutants from the surface of the sweat sensor electrode: Figure 12 As shown in the figure, the uncontaminated sensor surface is clean. After the sensor is used, inorganic salts, sugars, sebum, dandruff and other substances in sweat remain on the sensor electrode surface to form a contamination layer, which changes the sensor performance and causes errors in the measured signal. Using a micro-nano ultrasonic robot to clean the electrode surface can effectively remove the contamination layer and restore the electrode surface to a clean state. When the sensor is measured using cyclic voltammetry, the effects of sweat contamination and micro-nano ultrasonic robot cleaning on the current-potential (CV) curve are shown in the figure. Figure 13 As shown in the figure, when the test substance remains on the contaminated electrode surface, the signal peak value measured in the subsequent test will be too high. After cleaning by the micro-nano ultrasonic robot, the measured signal value will return to the initial level. When the sensor uses the chronoamperometry method for measurement, the effect of sweat contamination and micro-nano ultrasonic robot cleaning on the current-time (it) curve is shown in the figure. Figures 14 to 16 As shown in the figure, the sensor's concentration-current relationship is first calibrated using standard reagents. If the analyte remains on the contaminated electrode surface, the current signal measured in subsequent tests will be biased higher, resulting in a higher-than-actual concentration. After cleaning with the micro-nano ultrasonic robot, the residual material on the electrode surface is removed, restoring the measured current to pre-contamination levels and ensuring that the measured concentration is consistent with the actual value.

Claims

1. A sensor cleaning device based on a micro-nano ultrasonic robot, characterized in that: The invention comprises a vibration transmission platform and a micro-nano ultrasonic robot, wherein the vibration transmission platform comprises a substrate (2) and a piezoelectric ceramic transducer (3) adhered to the lower surface of the substrate (2), and the micro-nano ultrasonic robot comprises a shell (8) and bubbles (9) located in the shell (8), and the micro-nano ultrasonic robot is dispersed in a liquid medium; the shell (8) is made of mesoporous material, and the shell (8) is modified with biological enzymes or different types of drugs to achieve the removal of specific component pollutants on the surface of the electrode, and multiple bubbles (9) attract each other and merge to enhance the cleaning ability; the resonance frequency of the vibration transmission platform is 48kHz, the piezoelectric ceramic transducer (3) is used to generate mechanical vibration and make the vibration transmission platform resonate, thereby generating an ultrasonic field in the liquid medium, the bubbles (9) are forced to vibrate in the ultrasonic field and undergo periodic expansion-contraction cycles, and a locally enhanced acoustic flow field is generated on the surface of the bubbles (9) and in the nearby liquid to clean the sensor.

2. The sensor cleaning device according to claim 1, wherein The shell (8) contains a catalyst, the liquid medium contains a catalytic substrate, and the catalyst decomposes the catalytic substrate to generate bubbles (9).

3. The sensor cleaning device according to claim 1, wherein: The shell (8) is a polymer film, and the air bubble (9) is wrapped in the polymer film.

4. The sensor cleaning device according to claim 1, wherein The shell (8) is provided with a plurality of mutually unconnected cavities, the inner walls of the cavities being made of a hydrophobic material, and bubbles (9) are generated in the cavities when the shell (8) is dispersed in a liquid medium.

5. The sensor cleaning device according to claim 1, wherein: The shell (8) is a multi-layer tube, comprising a poly (3,4-ethylenedioxythiophene) (PEDOT) support layer, a SiO2 inner layer and a hydrophobic inner surface layer arranged layer by layer from the outside to the inside. When the shell (8) is dispersed in a liquid medium, bubbles (9) are generated inside.

6. The sensor cleaning device according to claim 1, wherein: It also includes a sensor, which is a planar electrochemical biosensor, including a counter electrode (4), a working electrode (5), and a reference electrode (6).

7. The sensor cleaning device according to claim 1, wherein: The substrate (2) is a quartz glass substrate.

8. A cleaning method for the sensor cleaning device according to any one of claims 1 to 7, characterized in that: The sensor to be cleaned is placed on a vibration transmission platform, and a liquid medium in which the micro-nano ultrasonic robot is dispersed is dripped onto the surface of the sensor to be cleaned, so that the piezoelectric ceramic transducer (3) generates mechanical vibration, and the vibration is transmitted to the liquid medium through the vibration transmission platform and the sensor to be cleaned, and the micro-nano ultrasonic robot in the liquid medium cleans the surface of the sensor to be cleaned.

9. The cleaning method according to claim 8, wherein A liquid storage tank (10) is provided between the surface to be cleaned of the sensor to be cleaned and the vibration transmission platform, and a liquid medium in which the micro-nano ultrasonic robots are dispersed is filled in the liquid storage tank (10).

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