Curved surface contact sensor and preparation method thereof

Abstract

The present invention provides a curved surface contact sensor and a preparation method thereof. It can be applied to the field of robot and sensor technology. The curved surface contact sensor includes a shell, a monocular camera, a contact module and a lighting module. The shell has an installation cavity, and the installation cavity has an open mouth; the monocular camera is arranged in the installation cavity; the contact module includes a black coating and a translucent silicone layer, the black coating is suitable for contacting with an object to be measured, and the contact surface between the black coating and the object to be measured and the opposite surface of the contact surface are both formed into a curved surface, the black coating is coated on the translucent silicone layer, the translucent silicone layer is connected to the shell, blocks the open mouth, and faces the monocular camera; the lighting module is arranged in the shell, and is used to illuminate the contact module. The curved surface contact sensor and the preparation method thereof provided by the present invention have high adaptability to robot tasks, good imaging quality and low manufacturing cost.

Description

Technical Field

[0001] The present invention relates to the field of sensor technology, and more specifically, to a curved surface contact sensor and a preparation method thereof. Background Art

[0002] In the prior art, tactile sensors are essential for robot manipulation because they can provide precise feedback about contact location and surface features of objects, enabling robots to perform more delicate and accurate operations. In recent years, vision-based tactile sensors have made significant progress due to their high resolution and low manufacturing cost, but most vision-based tactile sensor designs are based on planar configurations. Although some vision-based tactile sensor studies have explored curved surface designs to improve the adaptability of robot tasks, the sensor's internal multi-channel lighting system and the optical properties of the contact medium have reduced the flexibility of the sensor. At the same time, current vision-based tactile sensors usually use RGB cameras, binocular cameras, or depth cameras to capture the deformation of the sensing medium. Compared with tactile sensors based on capacitive, resistive, piezoresistive, and magnetic technologies, tactile sensors based on RGB cameras, binocular cameras, or depth cameras have lower operating frequencies, which may lead to missed detection and motion blur under dynamic contact, and severely limit their performance in dynamic tasks when integrated with the robot end effector. Event camera-based contact sensors provide an alternative way to capture high-frequency images, but they are usually too expensive. Summary of the invention

[0003] In view of this, the present invention provides a curved surface contact sensor with high adaptability to robot tasks, good imaging quality and low manufacturing cost, and a preparation method thereof.

[0004] One aspect of the present invention provides a curved contact sensor, comprising: a shell, the shell having an installation cavity, the installation cavity having an open mouth; a monocular camera, the monocular camera being arranged in the installation cavity; a contact module, the contact module comprising a black coating and a translucent silicone layer, the black coating being suitable for contacting an object to be measured, the contact surface between the black coating and the object to be measured and the opposite surface of the contact surface are both formed as curved surfaces, the black coating is applied to the translucent silicone layer, the translucent silicone layer is connected to the shell, blocks the open mouth, and faces the monocular camera; and a lighting module, the lighting module being arranged in the shell and used to illuminate the contact module.

[0005] According to the curved surface contact sensor of the embodiment of the present invention, the housing has an installation cavity, and the installation cavity has an open mouth; the monocular camera is arranged in the installation cavity; the contact module includes a black coating and a translucent silicone layer, the black coating is suitable for contacting with the object to be measured, the contact surface of the black coating and the object to be measured and the opposite surface of the contact surface are formed into a curved surface, the black coating is coated on the translucent silicone layer, the translucent silicone layer is connected to the housing, blocks the open mouth, and faces the monocular camera; the lighting module is arranged in the housing, and is used to illuminate the contact module. The curved surface contact sensor can achieve the purpose of detecting the position and surface shape characteristics of the object to be measured. The black coating is black, so that when the contact surface contacting the object to be measured is concave into the translucent silicone layer, the shadow of the concave boundary and the middle part within the boundary are very clear, the imaging of the monocular camera is better, and the result of predicting the position and surface shape of the object to be measured based on the change image obtained is more accurate. The contact surface of the black coating is a curved surface, which can be convenient for adapting to more objects to be measured to improve the adaptability to the task. The translucent silicone layer can have a suitable hardness and excellent tensile strength. The black coating can not only absorb internal light, but also prevent interference from ambient light, and can also serve as a wear-resistant protective layer. The contact module is directly opposite to the monocular camera, which makes it easier for the monocular camera to capture changing images, thereby facilitating the detection of the position and surface shape characteristics of the object to be tested. The monocular camera has a higher operating frequency, which can avoid missed detection and motion blur under dynamic contact, and the price of the monocular camera is relatively low, which can reduce the manufacturing cost of the curved contact sensor. The shell can provide an installation environment for the monocular camera, contact module and lighting module.

[0006] In some embodiments, the contact module further includes: a first transparent gel layer, wherein the first transparent gel layer is connected between the translucent silicone layer and the shell to seal the open opening.

[0007] In some embodiments, the contact module further includes: a rigid transparent layer, wherein the rigid transparent layer is connected between the first transparent gel layer and the shell to block the open opening.

[0008] In some embodiments, the contact module further includes: a second transparent gel layer, wherein the second transparent gel layer is connected between the rigid transparent layer and the shell to seal the open opening.

[0009] In some embodiments, the contact surface is parallel to the surface opposite to the contact surface, and the translucent silicone layer is coated on the first transparent gel layer with uniform thickness.

[0010] In some embodiments, the rigid transparent layer is a test tube, the second transparent gel layer fills the test tube, the open end of the test tube is embedded in the installation cavity, and the first transparent gel layer is coated on the outside of the test tube.

[0011] In some embodiments, the lighting module includes: a printed circuit board, the printed circuit board is arranged on the housing; and a light-emitting element, the light-emitting element is arranged on the printed circuit board and is electrically connected to a power supply circuit of the printed circuit board.

[0012] In some embodiments, the printed circuit board is annular, and a portion of the outer periphery of the open opening of the shell facing the side of the contact module protrudes toward the contact module, and the printed circuit board is sleeved outside the protrusion, or the printed circuit board is embedded in the protrusion; the black coating and the translucent silicone layer are connected to the printed circuit board.

[0013] In some embodiments, the lighting module further includes: a scattering member, which is annular and is mounted outside the protrusion along with the printed circuit board, or is embedded in the protrusion along with the printed circuit board, and the scattering member is located on a side of the printed circuit board close to the contact module, and the black coating and the translucent silicone layer are connected to the scattering member.

[0014] In some embodiments, the shell is made of black polylactic acid material.

[0015] In some embodiments, the shell includes: a base; a hollow sleeve, one end of the hollow sleeve is connected to the base, the hollow portion forms the installation cavity, the monocular camera is located in the installation cavity and connected to the base, the opening at the other end of the hollow sleeve is formed as the open port, the lighting module is arranged at the other end of the hollow sleeve, and the contact module is arranged at the other end of the hollow sleeve to seal the open port.

[0016] Another aspect of the present invention provides a method for preparing a curved contact sensor, which is used to prepare the curved contact sensor as described above, including: installing a lighting module on a shell; installing a monocular camera in an installation cavity of the shell; spraying a black abrasion-resistant mixture in a first molding cavity of a first mold, and then pressing in translucent silicone for casting to obtain a contact module, wherein the contact module includes a translucent silicone layer and a black coating composed of a black abrasion-resistant mixture, and an inner wall surface of the first molding cavity has the same shape as a contact surface of the black coating; connecting the contact module to the shell, sealing the open opening of the installation cavity, and facing the monocular camera.

[0017] According to the method for preparing the curved surface contact sensor of the embodiment of the present invention, the curved surface contact sensor of the present invention can be prepared, and the process is simple and easy to operate.

[0018] In some embodiments, the step of installing the lighting module on the housing includes: pressing the annular printed circuit board of the lighting module into the protrusion at the end of the hollow sleeve; and then pressing the annular scattering member into the protrusion, wherein the scattering member is adjacent to the printed circuit board.

[0019] The step of installing the monocular camera in the installation cavity of the shell includes: installing the monocular camera on the base of the shell.

[0020] The method also includes: inserting the open end of the test tube into the hollow part of the hollow sleeve with the printed circuit board and the scattering member to obtain a first intermediate member; placing the first intermediate member in an auxiliary tooling, pouring a transparent gel into the test tube, and curing it at room temperature for a first period of time to obtain a second intermediate member; spraying a release agent into a second molding cavity of a second mold, then pouring the transparent gel into the second molding cavity, pressing the other end of the second intermediate member opposite to the open end of the test tube into the second molding cavity, the auxiliary tooling is connected with the second mold, curing it for a second period of time at room temperature, and separating the transparent gel layer from the second molding cavity to obtain a third intermediate member.

[0021] The step of connecting the contact module to the shell and sealing the open mouth of the installation cavity includes: installing the auxiliary tooling with the third middle piece on the first mold, pressing one end of the transparent gel layer into the first molding cavity containing the black coating and the translucent silicone layer, curing at room temperature for a third period of time, separating the black coating from the first molding cavity, and obtaining a fourth middle piece; connecting one end of the hollow sleeve of the fourth middle piece to the base, the hollow part forms the installation cavity, the monocular camera is located in the installation cavity, and the contact module is opposite to the monocular camera. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The above and other objects, features and advantages of the present invention will become more apparent through the following description of the embodiments of the present invention with reference to the accompanying drawings, in which:

[0023] Figure 1 Schematically shows an exploded view of a curved surface contact sensor according to an embodiment of the present invention;

[0024] Figure 2 A schematic diagram of the structure of a curved surface contact sensor according to an embodiment of the present invention is shown;

[0025] Figure 3 The schematic diagram shows a structure in which a monocular camera according to an embodiment of the present invention is installed on a base;

[0026] Figure 4 The flowchart of the method for preparing the curved surface contact sensor according to the embodiment of the present invention is schematically shown.

[0027] Reference numerals:

[0028] Curved surface contact sensor 100,

[0029] Shell 1, mounting cavity 11, base 12, hollow sleeve 13, protrusion 131,

[0030] Monocular camera 2,

[0031] Contact module 3, black coating 31, translucent silicone layer 32, first transparent gel layer 35, rigid transparent layer 34, second transparent gel layer 33,

[0032] Lighting module 4 , printed circuit board 41 , light emitting element 42 , scattering element 43 . DETAILED DESCRIPTION

[0033] Below, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present invention. In the following detailed description, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of embodiments of the present invention. However, it is apparent that one or more embodiments may also be implemented without these specific details. In addition, in the following description, descriptions of known structures and technologies are omitted to avoid unnecessary confusion of concepts of the present invention.

[0034] In the technical solution of the present invention, the acquisition, storage and application of user personal information involved are in compliance with the provisions of relevant laws and regulations, necessary confidentiality measures are taken, and they do not violate public order and good morals. In the technical solution of the present invention, the acquisition, collection, storage, use, processing, transmission, provision, disclosure and application of data are in compliance with the provisions of relevant laws and regulations, necessary confidentiality measures are taken, and they do not violate public order and good morals.

[0035] The terms used herein are only for describing specific embodiments and are not intended to limit the present invention. The terms "comprise", "include", etc. used herein indicate the existence of the features, steps, operations and / or components, but do not exclude the existence or addition of one or more other features, steps, operations or components.

[0036] When using expressions such as "at least one of A, B or C, etc.", it should generally be interpreted in accordance with the meaning of the expression generally understood by those skilled in the art (for example, "a system having at least one of A, B or C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.). The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, features defined as "first" and "second" may explicitly or implicitly include one or more of the said features.

[0037] In the prior art, tactile sensors are essential for robot manipulation because they can provide precise feedback about contact location and surface features of objects, enabling robots to perform more delicate and accurate operations. In recent years, vision-based tactile sensors have made significant progress due to their high resolution and low manufacturing cost, but most vision-based tactile sensor designs are based on planar configurations. Although some vision-based tactile sensor studies have explored curved surface designs to improve the adaptability of robot tasks, the sensor's internal multi-channel lighting system and the optical properties of the contact medium have reduced the flexibility of the sensor. At the same time, current vision-based tactile sensors usually use RGB cameras, binocular cameras, or depth cameras to capture the deformation of the sensing medium. Compared with tactile sensors based on capacitive, resistive, piezoresistive, and magnetic technologies, tactile sensors based on RGB cameras, binocular cameras, or depth cameras have lower operating frequencies, which may lead to missed detection and motion blur under dynamic contact, and severely limit their performance in dynamic tasks when integrated with the robot end effector. Event camera-based contact sensors provide an alternative way to capture high-frequency images, but they are usually too expensive.

[0038] like Figure 1-Figure 4 As shown, an embodiment of the present invention provides a curved surface contact sensor 100 and a method for manufacturing the same.

[0039] like Figure 1 and Figure 2 As shown, the curved surface contact sensor 100 according to an embodiment of the present invention includes a housing 1, a monocular camera 2, a contact module 3 and a lighting module 4.

[0040] Specifically, combined Figure 1 and Figure 2The shell 1 has an installation cavity 11, and the installation cavity 11 has an open mouth; the monocular camera 2 is arranged in the installation cavity 11; the contact module 3 includes a black coating 31 and a translucent silicone layer 32, the black coating 31 is suitable for contacting the object to be measured, and the contact surface of the black coating 31 and the object to be measured and the opposite surface of the contact surface are both formed as curved surfaces, the black coating 31 is coated on the translucent silicone layer 32, the translucent silicone layer 32 is connected to the shell 1, blocks the open mouth, and faces the monocular camera 2; the lighting module 4 is arranged in the shell 1, and is used to illuminate the contact module 3.

[0041] It is understandable that the lighting module 4 can provide internal light by lighting the contact module 3. The black coating 31 is a structure in contact with the object to be tested. The black coating 31 will deform after contacting the object to be tested. The deformation of the black coating 31 causes the black coating 31 to be recessed into the translucent silicone layer 32. The black coating 31 applied to the translucent silicone layer 32 is designed to reflect internal light, and its brightness changes with contact. The monocular camera 2 can capture the changing image, and the position and surface shape characteristics of the object to be tested can be analyzed based on the changing image.

[0042] The black coating 31 is black so that when the contact surface with the object to be measured is recessed into the translucent silicone layer 32, the shadow of the recessed boundary and the middle part within the boundary are both very clear, the imaging of the monocular camera 2 is better, and the result of predicting the position and surface shape of the object to be measured based on the change image obtained is more accurate.

[0043] The contact surface of the black coating 31 is a curved surface, which can be easily adapted to more objects to be tested, so as to improve the adaptability to the task. The translucent silicone layer 32 can have a suitable hardness and excellent tensile strength. The black coating 31 can not only absorb internal light, but also prevent interference from ambient light, and can also serve as a wear-resistant protective layer.

[0044] The contact module 3 is directly opposite to the monocular camera 2, which can facilitate the monocular camera 2 to capture the changing image, thereby facilitating the detection of the position and surface shape characteristics of the object to be measured. The monocular camera 2 has a high operating frequency, which can avoid missed detection and motion blur under dynamic contact, and the price of the monocular camera 2 is low, which can reduce the manufacturing cost of the curved surface contact sensor 100. The housing 1 can provide an installation environment for the monocular camera 2, the contact module 3 and the lighting module 4.

[0045] According to the curved surface contact sensor 100 of the embodiment of the present invention, the housing 1 has an installation cavity 11, and the installation cavity 11 has an open mouth; the monocular camera 2 is arranged in the installation cavity 11; the contact module 3 includes a black coating 31 and a translucent silicone layer 32, the black coating 31 is suitable for contacting the object to be measured, and the contact surface of the black coating 31 and the object to be measured and the surface opposite to the contact surface are both formed as curved surfaces, the black coating 31 is coated on the translucent silicone layer 32, the translucent silicone layer 32 is connected to the housing 1, blocks the open mouth, and faces the monocular camera 2; the lighting module 4 is arranged in the housing 1, and is used to illuminate the contact module 3. The curved surface contact sensor 100 can achieve the purpose of detecting the position and surface shape characteristics of the object to be measured. The black coating 31 is black, so that when the contact surface contacting the object to be measured is concave into the translucent silicone layer 32, the shadows of the concave boundary and the middle part within the boundary are very clear, the imaging of the monocular camera 2 is better, and the result of predicting the position and surface shape of the object to be measured based on the change image obtained thereby is more accurate. The contact surface of the black coating 31 is a curved surface, which can be convenient for adapting to more objects to be tested, so as to improve the adaptability to the task. The translucent silicone layer 32 can have suitable hardness and excellent tensile strength. The black coating 31 can not only absorb internal light, but also prevent interference from ambient light, and can also serve as a wear-resistant protective layer. The contact module 3 is directly opposite to the monocular camera 2, which can facilitate the monocular camera 2 to capture changing images, thereby facilitating the detection of the position and surface shape characteristics of the object to be tested. The operating frequency of the monocular camera 2 is relatively high, which can avoid missed detection and motion blur under dynamic contact, and the price of the monocular camera 2 is relatively low, which can reduce the manufacturing cost of the curved contact sensor 100. The shell 1 can provide an installation environment for the monocular camera 2, the contact module 3 and the lighting module 4.

[0046] According to some embodiments of the present invention, Figure 1 and Figure 2 As shown, the contact module 3 may further include a first transparent gel layer 35, which is connected between the translucent silicone layer 32 and the housing 1 to block the opening. It is understandable that the first transparent gel layer 35 can provide support between the housing 1 and the translucent silicone layer 32, and the first transparent gel layer 35 can also assist in scattering the light of the lighting module 4, so that the monocular camera 2 can better image the black coating 31 and the translucent silicone layer 32.

[0047] In some embodiments of the present invention, Figure 1 and Figure 2As shown, the contact module 3 may further include a rigid transparent layer 34, which is connected between the first transparent gel layer 35 and the housing 1 to block the opening. It is understandable that the rigid transparent layer 34 can provide rigid support for the black coating 31, the translucent silicone layer 32 and the first transparent gel layer 35, and the support effect is good, so that the overall rigidity of the curved contact sensor 100 is better. The rigid transparent layer 34 can allow the deformation of the black coating 31 and the translucent silicone layer 32 to be clearly seen, and prevent the black coating 31 and the translucent silicone layer 32 from being delaminated or torn.

[0048] According to some embodiments of the present invention, Figure 1 and Figure 2 As shown, the contact module 3 may further include a second transparent gel layer 33, which is connected between the rigid transparent layer 34 and the housing 1 to block the open opening. It is understandable that the second transparent gel layer 33 can bond the rigid transparent layer 34 to the housing 1 to improve the stability of the connection between the rigid transparent layer 34 and the housing 1. The second transparent gel layer 33 can also scatter the light of the lighting module 4, so that the monocular camera 2 can better image the black coating 31 and the translucent silicone layer 32. Experiments have shown that there is a significant difference in imaging with or without the second transparent gel layer 33 between the rigid transparent layer 34 and the housing 1, and the imaging effect with the second transparent gel layer 33 is significantly better than the imaging effect without the second transparent gel layer 33.

[0049] According to some embodiments of the present invention, Figure 2 As shown, the contact surface is parallel to the opposite surface of the contact surface, and the translucent silicone layer 32 is uniformly coated on the first transparent gel layer 35. Thus, the black coating 31 is uniformly coated on the translucent silicone layer 32, and the translucent silicone layer 32 is uniformly coated on the first transparent gel layer 35. The uniformly coated black coating 31 and translucent silicone layer 32 can make the quality of the change image better, and the result of predicting the position and surface shape of the object to be measured by the change image is more accurate.

[0050] In some examples, considering the trade-off between fineness and depth in shape reconstruction, the thickness of the translucent silicone layer 32 is set to 1.5 mm based on in-depth experiments.

[0051] In some embodiments of the present invention, the rigid transparent layer 34 is a test tube, the second transparent gel layer 33 fills the test tube, the open end of the test tube is embedded in the mounting cavity 11, and the first transparent gel layer 35 is coated on the outside of the test tube. It can be understood that the test tube is easy to obtain and has a low cost, thereby making the manufacturing cost of the curved contact sensor 100 low. In some examples, the curvature of the curved surface of the end opposite to the open end of the test tube can be customized to be the same as the curvature of the contact surface of the black coating 31, the first transparent gel layer 35 is coated on the end opposite to the open end of the test tube, the translucent silicone layer 32 is coated on the first transparent gel layer 35, and the black coating 31 is coated on the translucent silicone layer 32, thereby making it easy to manufacture.

[0052] According to some embodiments of the present invention, Figure 1 and Figure 2 As shown, the lighting module 4 may include a printed circuit board 41 and a light emitting element 42. The printed circuit board 41 is disposed on the housing 1; the light emitting element 42 is disposed on the printed circuit board 41 and is electrically connected to the power supply circuit of the printed circuit board 41. Thus, the printed circuit board 41 can supply power to the light emitting element 42, and it is also convenient to fix the light emitting element 42 on the housing 1, and the light emitting element 42 can emit light to illuminate the contact module 3.

[0053] In some embodiments of the present invention, Figure 1 and Figure 2 As shown, the printed circuit board 41 may be annular, and the portion of the outer periphery of the open opening of the housing 1 facing the contact module 3 protrudes toward the contact module 3, and the printed circuit board 41 is sleeved outside the protrusion 131, or the printed circuit board 41 is embedded in the protrusion 131; the black coating 31 and the translucent silicone layer 32 are connected to the printed circuit board 41. It can be understood that the cooperation between the annular printed circuit board 41 and the protrusion 131 can facilitate the annular printed circuit board 41 to be stably fixed on the housing 1. The connection of the black coating 31 and the translucent silicone layer 32 to the printed circuit board 41 can facilitate the light-emitting element 42 to illuminate the black coating 31 and the translucent silicone layer 32, thereby achieving the purpose of lighting the contact module 3.

[0054] According to some embodiments of the present invention, Figure 1 and Figure 2 As shown, the lighting module 4 may further include a scattering member 43, which may be annular and sleeved outside the protrusion 131 with the printed circuit board 41, or embedded in the protrusion 131 with the printed circuit board 41. The scattering member 43 is located on the side of the printed circuit board 41 close to the contact module 3, and the black coating 31 and the translucent silicone layer 32 are connected to the scattering member 43. The scattering member 43 may scatter the light of the light-emitting element 42, and the image quality of the monocular camera 2 may be improved after the scattered light.

[0055] In some embodiments of the present invention, the housing 1 is made of black polylactic acid material, so that the housing 1 can absorb stray light and effectively guide the lighting path.

[0056] In some embodiments of the present invention, Figure 1-Figure 3 As shown, the housing 1 may include a base 12 and a hollow sleeve 13. One end of the hollow sleeve 13 is connected to the base 12, and the hollow portion is formed into a mounting cavity 11. The monocular camera 2 is located in the mounting cavity 11 and is connected to the base 12. The opening of the other end of the hollow sleeve 13 is formed into an open mouth. The lighting module 4 is disposed at the other end of the hollow sleeve 13, and the contact module 3 is disposed at the other end of the hollow sleeve 13 to block the open mouth. It can be understood that setting the housing 1 as the base 12 and the hollow sleeve 13 can facilitate the manufacture of the housing 1, and at the same time facilitate the installation of the lighting module 4, the contact module 3 and the monocular camera 2 in the housing 1, so that the contact module 3 is directly opposite to the monocular camera 2.

[0057] According to some embodiments of the present invention, due to the optical properties of the contact module 3, the lighting system uses a simple white LED ring to illuminate the curved contact sensor 100. Eight evenly distributed white LEDs and their corresponding 470 ohm resistors are soldered to a custom ring-shaped printed circuit board 41. The ring-shaped printed circuit board 41 is pressed into the housing 1, and a laser-cut double-sided frosted diffuser 43 is installed 10 mm above the ring-shaped printed circuit board 41 to achieve effective light diffusion. The emitted light passes through the diffuser 43 into the transparent gel layer and the translucent silicone layer 32, illuminates the black coating 31, and is then captured by the monocular camera 2.

[0058] According to some embodiments of the present invention, in order to achieve a compact design with a high response frequency, a global shutter monocular camera 2 is used, equipped with a 160-degree wide-angle (FoV) lens. The monocular camera 2 operates at a frame rate of 240fps and has an output resolution of 640*360 or 320*240. The monocular camera 2 is bolted to the base 12 and connected to a microcontroller, which is connected to the desktop via USB to transfer single-channel data. The exposure is set to manual mode to obtain consistent and stable output.

[0059] like Figure 4 As shown, the method for preparing a curved surface contact sensor according to an embodiment of the present invention is applied to prepare the curved surface contact sensor as described above, and includes steps 1 to 4.

[0060] In step 1, a lighting module is mounted on a housing.

[0061] In step 2, the monocular camera is installed in the installation cavity of the housing.

[0062] In step 3, a black abrasion-resistant mixture is sprayed into a first molding cavity of a first mold, and then a translucent silicone is pressed into the mold for casting to obtain a contact module. The contact module includes a translucent silicone layer and a black coating composed of a black abrasion-resistant mixture. The inner wall surface of the first molding cavity has the same shape as the contact surface of the black coating.

[0063] In step 4, the contact module is connected to the housing to seal the opening of the installation cavity so as to face the monocular camera.

[0064] According to the method for preparing the curved surface contact sensor of the embodiment of the present invention, the curved surface contact sensor of the present invention can be prepared through steps 1 to 4, and the process is simple and easy to operate.

[0065] According to some embodiments of the present invention, step 1: installing the lighting module on the housing comprises: pressing the annular printed circuit board of the lighting module into the protrusion at the end of the hollow sleeve; and then pressing the annular scattering member into the protrusion, the scattering member being adjacent to the printed circuit board.

[0066] Step 2: The step of installing the monocular camera in the installation cavity of the shell includes: installing the monocular camera on the base of the shell.

[0067] The method for preparing the curved surface contact sensor also includes steps 5 to 7.

[0068] Step 5: Insert the open end of the test tube into the hollow portion of the hollow sleeve with the printed circuit board and the scattering member to obtain a first intermediate member.

[0069] Step 6: Place the first intermediate piece in the auxiliary tooling, pour transparent gel into the test tube, and solidify it at room temperature for a first period of time to obtain the second intermediate piece.

[0070] Step 7: Spray the release agent into the second molding cavity of the second mold, then pour the transparent gel into the second molding cavity, press the other end of the second intermediate piece opposite to the open end of the test tube into the second molding cavity, connect the auxiliary tooling with the second mold, cure for a second period of time at room temperature, separate the transparent gel layer from the second molding cavity, and obtain the third intermediate piece.

[0071] Step 4: Connecting the contact module to the shell and sealing the open mouth of the installation cavity, including: installing the auxiliary tooling with the third middle piece on the first mold, pressing one end of the transparent gel layer into the first molding cavity containing the black coating and the translucent silicone layer, curing at room temperature for a third period of time, separating the black coating from the first molding cavity, and obtaining a fourth middle piece; connecting one end of the hollow sleeve of the fourth middle piece to the base, forming the hollow part into the installation cavity, the monocular camera is located in the installation cavity, and the contact module is opposite to the monocular camera.

[0072] Thus, the manufactured curved surface contact sensor includes a base, a monocular camera, a hollow sleeve, a printed circuit board, a light-emitting element, a scattering element, a second transparent gel layer, a transparent rigid layer, a first transparent gel layer, a translucent silicone layer and a black coating. The curved surface contact sensor manufactured by this embodiment has all the advantages described above.

[0073] It will be appreciated by those skilled in the art that the features described in the various embodiments of the present invention may be combined and / or combined in various ways, even if such combinations or combinations are not explicitly described in the present invention. In particular, without departing from the spirit and teachings of the present invention, the features described in the various embodiments of the present invention may be combined and / or combined in various ways. All of these combinations and / or combinations fall within the scope of the present invention.

[0074] The embodiments of the present invention are described above. However, these embodiments are only for the purpose of illustration, and are not intended to limit the scope of the present invention. Although each embodiment is described above, it does not mean that the measures in each embodiment cannot be used in combination advantageously. Without departing from the scope of the present invention, those skilled in the art may make various substitutions and modifications, which should all fall within the scope of the present invention.

Claims

1. A curved surface contact sensor, characterized in that: include: A housing, wherein the housing has a mounting cavity, and the mounting cavity has an open opening; A monocular camera, wherein the monocular camera is disposed in the mounting cavity; A contact module, wherein the contact module comprises a black coating and a translucent silicone layer, wherein the black coating is suitable for contacting with the object to be measured, wherein the contact surface between the black coating and the object to be measured and the surface opposite to the contact surface are both formed as curved surfaces, wherein the black coating is applied to the translucent silicone layer, wherein the translucent silicone layer is connected to the housing, blocks the open opening, and faces the monocular camera; A lighting module, which is disposed on the housing and is used to illuminate the contact module; Wherein, the contact module further includes: a first transparent gel layer, the first transparent gel layer being connected between the translucent silicone layer and the shell to block the open opening; Wherein, the contact module further includes: a rigid transparent layer, the rigid transparent layer being connected between the first transparent gel layer and the shell to block the open opening; Wherein, the contact module further includes: The second transparent gel layer is connected between the rigid transparent layer and the shell to block the open port. The rigid transparent layer is a test tube, and the second transparent gel layer fills the test tube.

2. The curved surface contact sensor according to claim 1, characterized in that: The contact surface is parallel to the surface opposite to the contact surface, and the translucent silicone layer is coated on the first transparent gel layer with uniform thickness.

3. The curved surface contact sensor according to claim 1, characterized in that: The open end of the test tube is embedded in the installation cavity, and the first transparent gel layer is coated on the outside of the test tube.

4. The curved surface contact sensor according to claim 1, characterized in that: The lighting module comprises: A printed circuit board, wherein the printed circuit board is arranged on the housing; A light emitting element is disposed on the printed circuit board and is electrically connected to a power supply circuit of the printed circuit board.

5. The curved surface contact sensor according to claim 4, characterized in that: The printed circuit board is annular, a portion of the outer periphery of the open opening of the housing facing the contact module protrudes toward the contact module, and the printed circuit board is sleeved outside the protrusion, or the printed circuit board is embedded in the protrusion; The black coating layer and the translucent silicone layer are connected to the printed circuit board.

6. The curved surface contact sensor according to claim 5, characterized in that: The lighting module further comprises: The scattering member is annular and is sleeved outside the protrusion along with the printed circuit board, or is embedded in the protrusion along with the printed circuit board. The scattering member is located on a side of the printed circuit board close to the contact module, and the black coating and the translucent silicone layer are connected to the scattering member.

7. The curved surface contact sensor according to claim 1, characterized in that: The shell is made of black polylactic acid material.

8. The curved surface contact sensor according to claim 1, characterized in that: The housing comprises: Base; A hollow sleeve, one end of the hollow sleeve is connected to the base, the hollow part forms the installation cavity, the monocular camera is located in the installation cavity and connected to the base, the opening at the other end of the hollow sleeve forms the open mouth, the lighting module is arranged at the other end of the hollow sleeve, and the contact module is arranged at the other end of the hollow sleeve to block the open mouth.

9. A method for preparing a curved surface contact sensor, used for preparing the curved surface contact sensor according to any one of claims 1 to 8, characterized in that: include: Installing the lighting module on the housing; Installing a monocular camera in the installation cavity of the housing; Spraying the black abrasion-resistant mixture into a first molding cavity of a first mold, and then pressing in translucent silicone for casting to obtain a contact module, wherein the contact module comprises a translucent silicone layer and a black coating composed of the black abrasion-resistant mixture, and the inner wall surface of the first molding cavity has the same shape as the contact surface of the black coating; The contact module is connected to the housing to block the open opening of the installation cavity so as to face the monocular camera.

10. The method for preparing a curved surface contact sensor according to claim 9, characterized in that: The step of installing the lighting module on the housing comprises: pressing the annular printed circuit board of the lighting module into the protrusion at the end of the hollow sleeve of the housing; and then pressing the annular scattering member into the protrusion, wherein the scattering member is adjacent to the printed circuit board; The step of installing the monocular camera in the installation cavity of the housing includes: installing the monocular camera on the base of the housing; The method further comprises: Inserting the open end of the test tube into the hollow portion of the hollow sleeve with the printed circuit board and the scattering member to obtain a first intermediate member; placing the first intermediate piece in an auxiliary tooling, pouring a transparent gel into the test tube, and curing at room temperature for a first period of time to obtain a second intermediate piece; Spraying a release agent into the second molding cavity of the second mold, then pouring a transparent gel into the second molding cavity, pressing the other end of the second intermediate piece opposite to the open end of the test tube into the second molding cavity, the auxiliary tooling is connected with the second mold in a coordinated manner, curing for a second period of time at room temperature, and separating the transparent gel layer from the second molding cavity to obtain a third intermediate piece; The step of connecting the contact module to the housing and sealing the open opening of the installation cavity comprises: Installing the auxiliary tooling with the third intermediate piece on the first mold, pressing one end of the transparent gel layer into the first molding cavity containing the black coating and the translucent silicone layer, curing at room temperature for a third period of time, and separating the black coating from the first molding cavity to obtain a fourth intermediate piece; One end of the hollow sleeve of the fourth middle piece is connected to the base, the hollow portion is formed into the installation cavity, the monocular camera is located in the installation cavity, and the contact module is directly opposite to the monocular camera.

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