Method, system, glove, device, and medium for manufacturing a flexible six-axis force sensor

Abstract

The application discloses a preparation method, system, glove, device and medium of a flexible six-dimensional force sensor, and belongs to the technical field of sensor technology. The preparation method of the flexible six-dimensional force sensor comprises the following steps: pouring a polydimethylsiloxane mixture into a mold with a preset microstructure to form a film, spraying multi-walled carbon nanotubes on the film to obtain a sensing unit; dropping a solution containing copper nanoparticles on a substrate to form a conductive layer and performing laser etching to obtain an electrode structure; pouring a polyimide solution on the substrate to form a flexible electrode film; and packaging the sensing unit and the flexible electrode film to obtain a flexible sensing unit, so as to prepare the flexible six-dimensional force sensor. The glove comprises the flexible six-dimensional force sensor and a signal processing module, and the signal processing module is used for calculating force information and / or torque information of the glove according to the resistance value of the flexible sensing unit in the flexible six-dimensional force sensor. The application can realize high-sensitivity and high-precision measurement of six-dimensional force.

Description

Technical Field

[0001] This application relates to the field of sensor technology, and in particular to a method, system, glove, device and medium for preparing a flexible six-dimensional force sensor. Background Technology

[0002] With the rapid development of measurement technology, force sensors play a crucial role in various fields such as aerospace, robotics, precision manufacturing, and biomedicine. These applications place higher demands on force sensors, such as higher sensitivity, wider measurement range, better dynamic performance, and greater environmental adaptability. Six-dimensional force sensors can simultaneously measure the force and torque acting on an object in three orthogonal directions, making them an important tool in the field of modern mechanical measurement. Although six-dimensional force sensors made of rigid materials can achieve six-dimensional force sensing, they are difficult to adapt to various deformations of soft interfaces and cannot fully adapt to various complex environments and task requirements. Especially in applications requiring high flexibility and environmental adaptability, such as wearable devices, soft robots, and remote medical surgical robots, traditional six-dimensional force sensors are inadequate.

[0003] Therefore, how to achieve high sensitivity and high precision measurement of six-dimensional forces is a technical problem that needs to be solved by those skilled in the art. Summary of the Invention

[0004] The purpose of this application is to provide a method, system, glove, device and medium for preparing a flexible six-dimensional force sensor, which can achieve high sensitivity and high precision measurement of six-dimensional forces.

[0005] To address the aforementioned technical problems, this application provides a method for fabricating a flexible six-dimensional force sensor, comprising:

[0006] Nylon powder is sintered using selective laser sintering technology to obtain a mold with a predetermined microstructure; wherein the predetermined microstructure is a microstructure containing multiple protrusions and depressions.

[0007] A polydimethylsiloxane mixture is poured into the mold to solidify the polydimethylsiloxane mixture in the mold to form a polydimethylsiloxane film; wherein the polydimethylsiloxane film has the predetermined microstructure;

[0008] Multi-walled carbon nanotubes are sprayed onto the surface of the polydimethylsiloxane film having the preset microstructure to obtain a sensing unit; wherein, the sensing unit is a polydimethylsiloxane film having the preset microstructure and sprayed with the multi-walled carbon nanotubes.

[0009] A solution containing copper nanoparticles is drop-coated onto a substrate to form a conductive layer;

[0010] The conductive layer is laser-etched to obtain the electrode structure;

[0011] A polyimide solution is poured onto the substrate to solidify the polyimide solution and form a flexible electrode film; wherein copper nanoparticles of the conductive layer are embedded on the surface of the flexible electrode film.

[0012] The sensing unit and the flexible electrode film are encapsulated face-to-face to obtain a flexible sensing unit; wherein, the surface of the sensing unit coated with the multi-walled carbon nanotubes is in contact with the surface of the flexible electrode film in which copper nanoparticles are embedded.

[0013] A flexible six-dimensional force sensor is fabricated using the aforementioned flexible sensing unit.

[0014] Optionally, a flexible six-dimensional force sensor is fabricated using the flexible sensing unit, comprising:

[0015] A sensor cover and a sensor base are fabricated; wherein the sensor cover and the sensor base are mortise and tenon structures with interlocking concave and convex joints, the sensor base includes 8 first bearing surfaces, adjacent first bearing surfaces have different orientations, and the sensor cover has a second bearing surface corresponding to each of the first bearing surfaces;

[0016] Eight flexible sensing units are encapsulated between a first film and a second film to form a flexible sensing unit array; wherein the eight flexible sensing units in the array are symmetrically arranged and on the same plane, the first film is a film made of polyimide, the second film is a film made of polydimethylsiloxane, the flexible electrode film in the flexible sensing unit is in contact with the first film, and the sensing unit in the flexible sensing unit is in contact with the second film;

[0017] The flexible sensing unit array is bent according to the shape of the sensor base, and the bent flexible sensing unit array is assembled between the sensor cover and the sensor base to obtain the flexible six-dimensional force sensor; wherein, each of the flexible sensing units in the flexible six-dimensional force sensor is embedded between the corresponding first bearing surface and the second bearing surface.

[0018] Optionally, the sensor cover and sensor base are fabricated, including:

[0019] The top cover mold and the base mold were prepared using 3D printing equipment;

[0020] A mixture of polydimethylsiloxane is poured into the upper cover mold and the base mold, and air bubbles are removed to obtain the sensor upper cover and the sensor base.

[0021] Optionally, after laser etching the conductive layer to obtain the electrode structure, and before casting the polyimide solution onto the substrate, the method further includes:

[0022] Remove the solution containing copper nanoparticles from the substrate.

[0023] This application also provides a glove, comprising:

[0024] The glove itself;

[0025] A flexible six-dimensional force sensor is disposed at a preset position on the glove body; wherein, the flexible six-dimensional force sensor is a flexible six-dimensional force sensor prepared by the above-mentioned method for preparing a flexible six-dimensional force sensor;

[0026] A signal processing module is connected to the flexible sensing unit in the flexible six-dimensional force sensor via a lead wire; wherein, the signal processing module is used to calculate the force information and / or torque information of the glove based on the resistance value of the flexible sensing unit.

[0027] Optionally, the signal processing module includes a computing unit, a voltage detection unit, and multiple fixed resistors;

[0028] Each of the fixed resistors is connected in series with the corresponding flexible sensing unit via the lead wire;

[0029] The voltage detection unit is used to detect the voltage signal across each of the fixed resistors;

[0030] The calculation unit is used to determine the force information and / or the torque information based on all the voltage signals.

[0031] Optionally, the process by which the calculation unit determines the force information and / or the torque information based on all the voltage signals includes: substituting the voltage signals into a mapping matrix to obtain the force information and / or the torque information; wherein the mapping matrix is ​​a matrix obtained through a static calibration experiment.

[0032] This application also provides a fabrication system for a flexible six-dimensional force sensor, comprising:

[0033] A laser sintering module is used to sinter nylon powder using selective laser sintering technology to obtain a mold with a preset microstructure; wherein the preset microstructure is a microstructure containing multiple protrusions and depressions;

[0034] The first casting module is used to cast the polydimethylsiloxane mixture into the mold, so that the polydimethylsiloxane mixture is cured in the mold to form a polydimethylsiloxane film; wherein the polydimethylsiloxane film has the preset microstructure;

[0035] A spraying module is used to spray multi-walled carbon nanotubes onto the surface of the polydimethylsiloxane film having the preset microstructure to obtain a sensing unit; wherein, the sensing unit is a polydimethylsiloxane film having the preset microstructure and sprayed with the multi-walled carbon nanotubes.

[0036] An electrode etching module is used to drop-coat a solution containing copper nanoparticles onto a substrate to form a conductive layer; it is also used to perform laser etching on the conductive layer to obtain an electrode structure.

[0037] The second casting module is used to cast a polyimide solution onto the substrate to solidify the polyimide solution and form a flexible electrode film; wherein, copper nanoparticles of the conductive layer are embedded on the surface of the flexible electrode film.

[0038] An encapsulation module is used to encapsulate the sensing unit and the flexible electrode film face-to-face to obtain a flexible sensing unit; wherein the surface of the sensing unit coated with the multi-walled carbon nanotubes is in contact with the surface of the flexible electrode film in which copper nanoparticles are embedded.

[0039] The fabrication module is used to fabricate a flexible six-dimensional force sensor using the flexible sensing unit.

[0040] This application also provides a storage medium storing a computer program thereon, which, when executed, performs the steps of the above-described method for preparing a flexible six-dimensional force sensor.

[0041] This application also provides an electronic device, including a memory and a processor, wherein the memory stores a computer program, and the processor, when calling the computer program in the memory, implements the steps of the above-described method for preparing a flexible six-dimensional force sensor.

[0042] This application provides a method for fabricating a flexible six-dimensional force sensor. In this method, nylon powder is sintered to obtain a mold with a predetermined microstructure. A polydimethylsiloxane mixture is then poured into the mold to form a polydimethylsiloxane film. The polydimethylsiloxane film contains a microstructure with multiple protrusions and depressions, which increases the contact area with the external environment. The flexible six-dimensional force sensor fabricated using the aforementioned polydimethylsiloxane film exhibits good responsiveness to external stimuli. This application further involves spraying multi-walled carbon nanotubes onto the surface of the polydimethylsiloxane film with the predetermined microstructure to obtain a sensing unit. Spraying multi-walled carbon nanotubes improves the conductivity and mechanical strength of the polydimethylsiloxane film. The flexible six-dimensional force sensor fabricated using the aforementioned sensing unit can quickly respond to changes in external force, improving measurement sensitivity. This application also involves drop-coating a copper nanoparticle solution onto a substrate and performing laser etching to form an electrode structure. A polyimide solution is then poured onto the substrate to obtain a flexible electrode film with copper nanoparticles embedded in the conductive layer on its surface. This flexible electrode film provides a stable electrical connection. This application encapsulates the sensing unit face-to-face with the flexible electrode film to obtain a flexible sensing unit, and then uses the flexible sensing unit to fabricate a flexible six-dimensional force sensor. It is evident that the flexible six-dimensional force sensor fabricated in the above manner can achieve high sensitivity and high precision measurement of six-dimensional forces. This application also provides a glove, a fabrication system for a flexible six-dimensional force sensor, a storage medium, and an electronic device, all possessing the aforementioned beneficial effects, which will not be elaborated upon further here. Attached Figure Description

[0043] To more clearly illustrate the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0044] Figure 1 A flowchart illustrating a method for fabricating a flexible six-dimensional force sensor provided in an embodiment of this application;

[0045] Figure 2 This is a schematic diagram illustrating the fabrication process of a flexible sensing unit provided in an embodiment of this application;

[0046] Figure 3 This is a schematic diagram illustrating the fabrication process of a flexible six-dimensional force sensor provided in an embodiment of this application.

[0047] Figure 4 This is a schematic diagram of a flexible six-dimensional force sensor structure provided in an embodiment of this application;

[0048] Figure 5This is a schematic diagram of a smart data glove structure provided in an embodiment of this application;

[0049] Figure 6 This is a static calibration flowchart provided in an embodiment of this application;

[0050] Figure 7 This is a schematic diagram of a sensor experimental calibration curve provided in an embodiment of this application;

[0051] Figure 8 This is a schematic diagram of a massage therapy technique provided in an embodiment of this application. Detailed Implementation

[0052] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0053] Please see below. Figure 1 , Figure 1 This is a flowchart illustrating a method for fabricating a flexible six-dimensional force sensor provided in an embodiment of this application.

[0054] Specific steps may include:

[0055] S101: Nylon powder is sintered using selective laser sintering technology to obtain a mold with a pre-defined microstructure;

[0056] In this embodiment, the relevant operations of S101 to S108 can be completed jointly by staff and electronic equipment; this embodiment can also be applied to electronic equipment with sensor preparation function, and the electronic equipment can realize the relevant operations of S101 to S108 by running the program.

[0057] Before this step, nylon powder can be placed inside a mold, and then sintered using selective laser sintering (SLS) technology. The sintered nylon powder and the mold form a single unit. After sintering the nylon powder, a mold with a predetermined microstructure is obtained. This predetermined microstructure includes multiple protrusions and recesses; the mold can be a mold with a flat bottom. Specifically, in this embodiment, a high-energy laser beam can be used to melt the nylon powder, forming the desired shape layer by layer, thereby obtaining a mold with the predetermined microstructure.

[0058] S102: The polydimethylsiloxane mixture is poured into the mold to allow the polydimethylsiloxane mixture to solidify in the mold to form a polydimethylsiloxane film;

[0059] The polydimethylsiloxane mixture (also known as PDMS mixture) comprises polydimethylsiloxane PDMS and a curing agent. In this embodiment, the liquid PDMS mixture is poured into a pre-prepared mold, filling all voids and creating a predetermined microstructure. After casting, the mold is placed under appropriate conditions to allow the PDMS mixture to undergo a cross-linking reaction, curing within the mold to form a polydimethylsiloxane film (also known as a PDMS film). One surface of the aforementioned polydimethylsiloxane film has the predetermined microstructure. After curing, the PDMS film can be removed from the mold. The predetermined microstructure of the PDMS film increases its surface area, enhancing its contact area with the external environment and thus improving the sensor's sensitivity.

[0060] S103: Spray multi-walled carbon nanotubes onto the surface of the polydimethylsiloxane film having a predetermined microstructure to obtain a sensing unit;

[0061] In this embodiment, multi-walled carbon nanotubes (MWCNTs) are nanoscale tubular structures formed by winding multiple layers of graphene. In this embodiment, the MWCNTs are pre-dispersed in a solvent to form a uniform suspension, allowing them to be sprayed onto the surface of the polydimethylsiloxane (PDMS) film having the predetermined microstructure. After spraying and curing, the MWCNTs and the PDMS film form a tight bond, creating a sensing unit. The aforementioned sensing unit is a polydimethylsiloxane film with the predetermined microstructure and coated with the MWCNTs.

[0062] S104: A solution containing copper nanoparticles is drop-coated onto a substrate to form a conductive layer;

[0063] In this embodiment, a solution containing copper nanoparticles can be drop-coated onto a flat substrate using a drop-coating method. The substrate can be glass, silicon wafer, or other suitable materials.

[0064] S105: The conductive layer is laser-etched to obtain the electrode structure;

[0065] In this step, the conductive layer can be laser-etched according to a preset image to obtain the electrode structure. The shape of the electrode structure is consistent with the preset image.

[0066] S106: A polyimide solution is poured onto the substrate to solidify the polyimide solution and form a flexible electrode film;

[0067] Polyimide (PI) is a high-performance polymer. In this step, an appropriate amount of PI solution is poured onto the substrate to ensure complete coverage of the conductive layer. After the polyimide solution cures to form a flexible electrode film, copper nanoparticles from the conductive layer are embedded on the surface of the flexible electrode film.

[0068] When the electronic device performs this step, the electronic device can determine whether there is a solution containing copper nanoparticles on the substrate; if there is no solution containing copper nanoparticles on the substrate, the relevant operation of S106 can be performed directly; if there is a solution containing copper nanoparticles on the substrate, after laser etching the conductive layer to obtain the electrode structure, before pouring the polyimide solution into the conductive layer (pouring the polyimide solution into the substrate), the solution containing copper nanoparticles on the substrate can also be removed.

[0069] S107: The sensing unit and the flexible electrode film are encapsulated face-to-face to obtain a flexible sensing unit;

[0070] In this embodiment, the sensing unit and the flexible electrode film can be encapsulated face-to-face. During encapsulation, the surface of the sensing unit coated with the multi-walled carbon nanotubes needs to be in contact with the surface of the flexible electrode film embedded with copper nanoparticles. After encapsulation, a flexible sensing unit is obtained, which can sense pressure changes and convert them into electrical signal output. The flexible sensing unit includes a sensing unit and a flexible electrode film.

[0071] S108: A flexible six-dimensional force sensor is fabricated using the flexible sensing unit.

[0072] After obtaining the flexible sensing unit, multiple flexible sensing units (such as at least 8 flexible sensing units) can be encapsulated between the sensor cover and the sensor base to obtain a flexible six-dimensional force sensor.

[0073] In this embodiment, a mold with a predetermined microstructure is obtained by sintering nylon powder. A polydimethylsiloxane (PDS) film is then formed by casting a polydimethylsiloxane mixture into the mold. The PDS film contains a microstructure with multiple protrusions and depressions, which increases the contact area with the external environment. The flexible six-dimensional force sensor prepared using the aforementioned PDS film exhibits good responsiveness to external stimuli. In this embodiment, multi-walled carbon nanotubes are sprayed onto the surface of the PDS film with the predetermined microstructure to obtain a sensing unit. Spraying multi-walled carbon nanotubes improves the conductivity and mechanical strength of the PDS film. The flexible six-dimensional force sensor prepared using the aforementioned sensing unit can quickly respond to changes in external force, improving measurement sensitivity. In this embodiment, a copper nanoparticle solution is drop-coated onto a substrate and laser-etched to form an electrode structure. A polyimide solution is then cast onto the substrate to obtain a flexible electrode film with copper nanoparticles embedded in the conductive layer on its surface. This flexible electrode film provides a stable electrical connection. In this embodiment, the sensing unit and the flexible electrode film are encapsulated face-to-face to obtain a flexible sensing unit, and a flexible six-dimensional force sensor is fabricated using the flexible sensing unit. It is evident that the flexible six-dimensional force sensor fabricated in the above manner can achieve high sensitivity and high precision measurement of six-dimensional forces.

[0074] As for Figure 1 A further description of the corresponding embodiment shows that a flexible six-dimensional force sensor can be fabricated using the flexible sensing unit in the following manner:

[0075] Step A1: Prepare the sensor cover and sensor base;

[0076] The process of preparing the sensor cover and sensor base specifically involves: using 3D printing equipment to prepare the cover mold and the base mold; pouring a polydimethylsiloxane mixture into the cover mold and the base mold and removing air bubbles to obtain the sensor cover and the sensor base.

[0077] In this embodiment, the sensor cover and the sensor base are mortise and tenon structures with interlocking concave and convex shapes. The sensor base includes eight first bearing surfaces, and adjacent first bearing surfaces have different orientations. The sensor cover has a second bearing surface corresponding to each of the first bearing surfaces.

[0078] Step A2: Encapsulate the eight flexible sensing units between the first thin film and the second thin film to form a flexible sensing unit array;

[0079] In this flexible sensing unit array, eight flexible sensing units are symmetrically arranged and located on the same plane. The first film is a film made of polyimide, and the second film is a film made of polydimethylsiloxane. The flexible electrode film in the flexible sensing unit is in contact with the first film, and the sensing unit in the flexible sensing unit is in contact with the second film.

[0080] The flexible sensing unit array, from top to bottom, consists of: a thin film made of polydimethylsiloxane (i.e., the second thin film), a sensing unit, a flexible electrode thin film, and a thin film made of polyimide (the first thin film).

[0081] Step A3: Bend the flexible sensing unit array according to the shape of the sensor base, and assemble the bent flexible sensing unit array between the sensor cover and the sensor base to obtain the flexible six-dimensional force sensor.

[0082] In this flexible six-dimensional force sensor, each flexible sensing unit is embedded between the corresponding first and second bearing surfaces. That is, the first surface of the flexible sensing unit is in contact with the first bearing surface, and the second surface of the flexible sensing unit is in contact with the second bearing surface.

[0083] Based on the above-mentioned method for preparing a flexible six-dimensional force sensor, this application also proposes a glove capable of detecting six-dimensional force. The glove includes a glove body, a flexible six-dimensional force sensor, a signal processing module, and a power supply device.

[0084] The aforementioned flexible six-dimensional force sensor can be disposed at a preset position on the glove body (such as the fingertip or fingertip). The aforementioned flexible six-dimensional force sensor is prepared according to the preparation method of the flexible six-dimensional force sensor provided in the above embodiment.

[0085] The aforementioned signal processing module is connected to the flexible sensing unit in the flexible six-dimensional force sensor via leads; the signal processing module can calculate the force information and / or torque information of the glove based on the resistance value of the flexible sensing unit.

[0086] The flexible six-dimensional force sensor in the above-mentioned glove includes a flexible sensing unit obtained by face-to-face encapsulation of a sensing unit and a flexible electrode film. The sensing unit is a polydimethylsiloxane film with the preset microstructure and coated with the multi-walled carbon nanotubes. Therefore, the glove provided in this embodiment can achieve high sensitivity and high precision measurement of six-dimensional force.

[0087] As a corresponding Figure 1In a further description of the corresponding embodiment, the signal processing module includes a calculation unit, a voltage detection unit, and multiple fixed resistors; the number of fixed resistors is consistent with the number of flexible sensing units, that is, there is a one-to-one correspondence between the fixed resistors and the flexible sensing units.

[0088] Each of the fixed resistors is connected in series with the corresponding flexible sensing unit via the lead; the voltage detection unit is used to detect the voltage signal across each of the fixed resistors.

[0089] When subjected to pressure deformation, the resistance value of the flexible sensing unit changes, and the voltage across the fixed resistor connected in series with the flexible sensing unit also changes accordingly. Therefore, the calculation unit can determine the force information and / or the torque information based on the voltage signals across all the fixed resistors.

[0090] As a feasible implementation, the process by which the calculation unit determines the force information and / or the torque information based on the voltage signal includes: substituting the voltage signal into a mapping matrix to obtain the force information and / or the torque information; wherein, the mapping matrix is ​​a matrix obtained through static calibration experiments. The mapping matrix is ​​used to represent the mapping relationship between the voltage signal and the force information, and can also be used to represent the mapping relationship between the voltage signal and the torque information. Specifically, in this embodiment, the value of the voltage signal can be multiplied by the mapping matrix Gc to obtain the corresponding force information and torque information.

[0091] The process described in the above embodiments is illustrated below through examples in practical applications.

[0092] With changes in people's lifestyles and work habits, prolonged use of electronic devices with heads down, incorrect sitting postures at work, and lack of exercise have become increasingly common, leading to a significant increase in the incidence of cervical spondylosis, which has shown a growing trend towards affecting younger people in recent years. Neck and shoulder pain not only affects patients' quality of life but can also lead to a series of serious complications. Currently, massage therapy is one of the effective methods for treating and relieving neck and shoulder pain. The application of force during massage therapy is complex, and its effectiveness highly depends on the physician's subjective perception and medical experience; experienced physicians generally achieve better treatment results. Even with the same hand gestures, incorrect force application during massage therapy can significantly reduce pain relief. Existing sensor equipment struggles to accurately measure the magnitude and direction of the physician's massage force, severely limiting the improvement of massage therapy's effectiveness and hindering the provision of precise teaching guidance in the training of massage therapists.

[0093] The emergence of flexible six-dimensional force sensors has overcome the shortcomings of rigid sensors. They possess unique advantages such as softness, flexibility, deformability, and good environmental adaptability, enabling not only conformal measurements on complex surfaces but also adaptability to mechanical measurement needs in various unstructured environments. By installing sensors and signal processing modules on gloves, they can become intelligent data gloves capable of real-time detection of six-dimensional massage force on each finger of the wearer during massage therapy.

[0094] The six-dimensional force sensor in the related technology senses force / torque in various directions by attaching strain gauges at different locations. A Wheatstone full-bridge circuit converts the resistance changes of the strain gauges into a voltage output. The force on the six-dimensional force sensor is then calculated based on the input (force F) and output (voltage output of the full-bridge circuit). However, the six-dimensional force sensor in the aforementioned technology is a rigid sensor and is relatively large, making it unsuitable for flexible devices such as wearable medical devices.

[0095] The smart data gloves in related technologies are equipped with strain gauge sensors, gyroscope sensors, and flexure sensing strips at the fingers, which can collect data on the wearer's finger joint movements. However, these smart data gloves, used to collect hand movement data, cannot collect and detect the six-dimensional forces at the fingers.

[0096] Please see Figure 2 , Figure 2 This is a schematic diagram of the fabrication process of a flexible sensing unit provided in an embodiment of this application. The operations involved include: selective laser sintering, PDMS casting, peeling to obtain mPDMS, coating MWCNTs thin film, drop coating CN, laser etching for imaging, casting PI, separating the PI with CN, and encapsulating the sensing unit to finally obtain the flexible sensing unit.

[0097] The flexible sensing unit comprises two parts: a polydimethylsiloxane (PDMS) film coated with multi-walled carbon nanotubes (MWCNTs) possessing a surface microstructure, and a flexible electrode. First, 3D printing is performed using selective laser sintering (SLS) technology, where nylon powder is selectively sintered under laser irradiation to form the desired shape layer by layer (i.e., a microstructure shape with an uneven surface). The 3D printing process is carried out in a mold containing the sintered microstructure. In this embodiment, a PDMS mixture can also be cast into the laser-sintered mold. After peeling and curing, the PDMS replicating the surface microstructure of the mold is obtained, resulting in a surface microstructured PDMS (mPDMS) film. MWCNTs are then deposited onto the mPDMS surface using a spraying technique to further obtain a multi-walled carbon nanotube coated PDMS film (MWCNTs / mPDMS) with a surface microstructure.

[0098] In fabricating flexible electrodes, dispersed copper nanoparticles (CN) are drop-coated onto a flat substrate to form a highly conductive layer. This layer is then patterned using laser etching to obtain electrodes on a rigid substrate (i.e., the electrodes left after laser etching). Polyimide (PI) is poured onto the substrate and cured to obtain the flexible electrode, allowing the patterned copper nanoparticles to be firmly embedded in its surface and separating the PI film from the substrate. MWCNTs / mPDMS are then encapsulated with the flexible electrode film, and after the conductive layers are in face-to-face contact, a flexible sensing unit is obtained.

[0099] "Imaging" refers to forming a designed pattern on the surface of drop-coated copper nanoparticles through laser etching. The specific image formed by imaging can be an interdigitated electrode pattern, which is an electrode with a finger-like or comb-like pattern.

[0100] Please see Figure 3 , Figure 3 This is a schematic diagram of the fabrication process of a flexible six-dimensional force sensor provided in an embodiment of this application. The materials and devices involved include a PDMS mixture configured in a 10:1 ratio, a top cover mold, a base mold, a sensing unit, a flexible electrode, a PI film, and a flexible sensing unit array. The operations involved include heating at 60°C for 3 hours, demolding, encapsulation, bending, assembly, and bonding, ultimately obtaining a flexible six-dimensional force sensor.

[0101] The fabrication process of the flexible six-dimensional force sensor is as follows: A sensor cover and base mold are prepared using 3D printing. A mixture of polydimethylsiloxane (PDMS) and a curing agent is then prepared in a 10:1 ratio. The PDMS mixture is vacuum-treated to remove air bubbles, poured into the mold, and heated at 60°C for 3 hours. After the PDMS solution solidifies, it is demolded to obtain the sensor cover and base. The flexible sensing unit array consists of four parts: a bottom layer of PI film, on which eight flexible electrodes are symmetrically attached; the sensing units are multi-walled carbon nanotubes (MWCNTs) coated PDMS films with surface microstructures, and the sensing units are in face-to-face contact with the flexible electrodes; finally, the top layer of PDMS film covers the first three parts and is encapsulated using an acrylic adhesive. Next, the flexible sensing unit array is bent in space, and the sensor cover, flexible sensing unit array, and sensor base are bonded together using an acrylic adhesive to obtain the flexible six-dimensional force sensor.

[0102] Please see Figure 4 , Figure 4 This is a schematic diagram of a flexible six-dimensional force sensor structure provided in an embodiment of this application. 401 is the sensor cover, 402 is the flexible sensing unit array after bending, and 403 is the sensor base. S in the figure is the first bearing surface of the sensor base.

[0103] The sensor cover and sensor base adopt a mortise and tenon structure similar to that of traditional Chinese architecture. From top to bottom, the components are the sensor cover, the flexible sensor unit array, and the sensor base. The shapes of the cover and base are interlocked, and the flexible sensor unit array can be bent to fit perfectly between the sensor cover and the base.

[0104] Please see Figure 5 , Figure 5 This is a schematic diagram of a smart data glove structure provided in an embodiment of this application. Flexible six-dimensional force sensors are installed at the center of the fingertips of each of the five fingers of the smart data glove. The flexible six-dimensional force sensors are bonded to the smart data glove using hot melt adhesive. Eight leads are connected to the flexible electrodes of the eight flexible sensing units of each flexible six-dimensional force sensor. The eight leads of each flexible six-dimensional force sensor are integrated and connected to the signal processing module on the back of the smart data glove.

[0105] The signal processing module is bonded to the back of the smart data glove using hot melt adhesive. The signal processing module consists of the following four parts: a circuit board with a microcontroller, a Bluetooth communication module, a 400mAh rechargeable lithium battery, and a protective shell.

[0106] The Bluetooth communication module is soldered onto the circuit board, which is then secured to the protective housing base with screws. The lithium battery is fixed in a slot on the protective housing cover. Their functions are as follows: the microcontroller processes multiple acquired voltage signals; the Bluetooth communication module transmits the acquired voltage signals to the host computer; the rechargeable lithium battery powers the sensors and signal processing module; and the protective housing secures the development board and lithium battery and provides protection.

[0107] The unique structure of the flexible six-dimensional force sensor allows for multiple contact deformation modes under external force stimulation from different directions. Under these different deformation modes, the eight sensing units of the flexible sensor array undergo varying deformations, resulting in changes in resistance. In the circuit of the flexible sensor array, each sensing unit is connected in series with a 5kΩ external fixed resistor. When the resistance of a sensing unit changes, the voltage across the fixed resistor changes. This voltage signal change is transmitted to the signal processing module via flexible electrodes and leads. The signal processing module acquires the voltage signal changes from the sensor and transmits them sequentially to the host computer for voltage-force / torque conversion, starting from the thumb and working backwards.

[0108] The voltage-force / torque conversion process is as follows: First, the sensor is statically calibrated using a static loading calibration platform. The experimental calibration curve is obtained by sequentially applying six-dimensional forces to the sensor. Based on the sensor's experimental calibration curve, the sensor's voltage at F... x and F y The directional range is -1.5N to 1.5N, Fz The range is -2N to 0N, M x M y and M z The range is -5 N·mm to 5 N·mm. When the force and torque detection range exceeds the range, the voltage change of the sensing unit is too small to distinguish pressure changes.

[0109] Please see Figure 6 , Figure 6 A static calibration flowchart provided in this application embodiment includes the following steps: After static calibration begins, the system warms up and starts the calibration software, measures and filters the branch output voltage signal, performs a six-dimensional sequential loading operation, calculates the calibration matrix and performance indicators, and the static calibration ends. The six-dimensional sequential loading operation includes: clearing the initial voltage of each branch to zero, setting each force / torque in each dimension to a loading point of 1 kgf / 0.1 kgf·m, adding / unloading weights, collecting the output voltage of each branch, and saving the voltage data; determining whether loading is complete; if not, proceeding to the weight addition / unloading operation; if complete, determining whether the data is abnormal; if the data is abnormal, proceeding to the operation of clearing the initial voltage of each branch to zero; if the data is not abnormal, proceeding to the step of calculating the calibration matrix and performance indicators.

[0110] Please see Figure 7 , Figure 7 This is a schematic diagram of a sensor experimental calibration curve provided in an embodiment of this application. In the figure, (a), (b), and (c) represent forces F in three directions, respectively. x F y F z The correspondence with ΔV / V0, (d), (e), and (f) represent the torque M in the three directions, respectively. x M y and M z The correspondence between N and ΔV / V0. N represents Newtons, and mm represents millimeters. S1, S2, S3, S4, S5, S6, S7, and S8 represent the sensing units among the eight flexible sensing units. V0 is the voltage across the 5kΩ fixed resistor connected to the sensor's measuring circuit when no external force is applied, and ΔV is the difference between the voltage across the fixed resistor and the initial V0 after an external force is applied.

[0111] The mapping relationship between the applied rated force / torque and the branch output voltage is: F s =G c U;

[0112] In the above formula: F s Represents the six-dimensional spatial calibration force; U represents the output voltage of the measuring branch sensing unit; G c This represents the mapping matrix between the calibration force and the output voltage of the measurement branch.

[0113] If a six-dimensional force sensor is an ideal linear system, then only six linearly independent six-dimensional calibration forces need to be applied to it, and the calibration matrix can be obtained from the output voltage of the measured branch sensing unit. However, in reality, the input and output of the sensor are usually not ideally linear. Therefore, it is necessary to apply multiple loads at multiple points within the sensor's measurement range to obtain multiple sets of data, and then use a backpropagation neural network algorithm based on genetic algorithm optimization (GA-BP algorithm) to map and calibrate the data, finally determining the mapping relationship between the input and output quantities, and obtaining the calibration matrix.

[0114] The smart data glove in this embodiment can collect information on the magnitude and direction of the six-dimensional massage force of seven commonly used massage therapy techniques. Please refer to [link / reference]. Figure 8 , Figure 8 This is a schematic diagram of a massage therapy technique provided in an embodiment of this application. Figure 8 The seven massage techniques include: (a) straight push, (b) separating push, (c) rotating push, (d) grasping and pinching, (e) light tapping, (f) fingertip pressing, and (g) twisting.

[0115] like Figure 8 As shown, the collected information can be used to construct a force information dataset for massage therapy, which can then be used to train a remote massage therapy robot. During massage therapy training, the six-dimensional massage force of the wearer of the smart data glove can be detected. By comparing this force with existing force information datasets, visualized quantitative analysis and guidance can be provided, improving teaching efficiency.

[0116] This embodiment provides a method for fabricating a flexible six-dimensional force sensor. The sensor produced has advantages such as small size, high sensitivity, and small error, enabling accurate force and torque measurement. The sensor mold is reusable, and the fabrication method is highly economical. The intelligent data glove designed in this embodiment can collect six-dimensional massage force information of each finger in various commonly used massage techniques. This can not only construct a force information dataset for massage therapy, but also perform visualized quantitative analysis of the massage force of the wearer during massage training, improving teaching efficiency.

[0117] This application also provides a fabrication system for a flexible six-dimensional force sensor, which may include:

[0118] A laser sintering module is used to sinter nylon powder using selective laser sintering technology to obtain a mold with a preset microstructure; wherein the preset microstructure is a microstructure containing multiple protrusions and depressions;

[0119] The first casting module is used to cast the polydimethylsiloxane mixture into the mold, so that the polydimethylsiloxane mixture is cured in the mold to form a polydimethylsiloxane film; wherein the polydimethylsiloxane film has the preset microstructure;

[0120] A spraying module is used to spray multi-walled carbon nanotubes onto the surface of the polydimethylsiloxane film having the preset microstructure to obtain a sensing unit; wherein, the sensing unit is a polydimethylsiloxane film having the preset microstructure and sprayed with the multi-walled carbon nanotubes.

[0121] An electrode etching module is used to drop-coat a solution containing copper nanoparticles onto a substrate to form a conductive layer; it is also used to perform laser etching on the conductive layer to obtain an electrode structure.

[0122] The second casting module is used to cast a polyimide solution onto the substrate to solidify the polyimide solution and form a flexible electrode film; wherein, copper nanoparticles of the conductive layer are embedded on the surface of the flexible electrode film.

[0123] An encapsulation module is used to encapsulate the sensing unit and the flexible electrode film face-to-face to obtain a flexible sensing unit; wherein the surface of the sensing unit coated with the multi-walled carbon nanotubes is in contact with the surface of the flexible electrode film in which copper nanoparticles are embedded.

[0124] The fabrication module is used to fabricate a flexible six-dimensional force sensor using the flexible sensing unit.

[0125] In this embodiment, a mold with a predetermined microstructure is obtained by sintering nylon powder. A polydimethylsiloxane (PDS) film is then formed by casting a polydimethylsiloxane mixture into the mold. The PDS film contains a microstructure with multiple protrusions and depressions, which increases the contact area with the external environment. The flexible six-dimensional force sensor prepared using the aforementioned PDS film exhibits good responsiveness to external stimuli. In this embodiment, multi-walled carbon nanotubes are sprayed onto the surface of the PDS film with the predetermined microstructure to obtain a sensing unit. Spraying multi-walled carbon nanotubes improves the conductivity and mechanical strength of the PDS film. The flexible six-dimensional force sensor prepared using the aforementioned sensing unit can quickly respond to changes in external force, improving measurement sensitivity. In this embodiment, a copper nanoparticle solution is drop-coated onto a substrate and laser-etched to form an electrode structure. A polyimide solution is then cast onto the substrate to obtain a flexible electrode film with copper nanoparticles embedded in the conductive layer on its surface. This flexible electrode film provides a stable electrical connection. In this embodiment, the sensing unit and the flexible electrode film are encapsulated face-to-face to obtain a flexible sensing unit, and a flexible six-dimensional force sensor is fabricated using the flexible sensing unit. It is evident that the flexible six-dimensional force sensor fabricated in the above manner can achieve high sensitivity and high precision measurement of six-dimensional forces.

[0126] Furthermore, the process of fabricating a flexible six-dimensional force sensor using the flexible sensing unit includes: fabricating a sensor cover and a sensor base; wherein the sensor cover and the sensor base are interlocking mortise and tenon structures, the sensor base includes eight first bearing surfaces, adjacent first bearing surfaces have different orientations, and the sensor cover has a second bearing surface corresponding to each of the first bearing surfaces; encapsulating the eight flexible sensing units between a first thin film and a second thin film to form a flexible sensing unit array; wherein the eight flexible sensing units in the flexible sensing unit array are symmetrically arranged and located on the same plane, The first film is a film made of polyimide, and the second film is a film made of polydimethylsiloxane. The flexible electrode film in the flexible sensing unit is in contact with the first film; the sensing unit in the flexible sensing unit is in contact with the second film; the flexible sensing unit array is bent according to the shape of the sensor base, and the bent flexible sensing unit array is assembled between the sensor cover and the sensor base to obtain the flexible six-dimensional force sensor; wherein, each flexible sensing unit in the flexible six-dimensional force sensor is embedded between the corresponding first bearing surface and the second bearing surface.

[0127] Furthermore, the process of fabricating the sensor cover and sensor base includes: using 3D printing equipment to fabricate a cover mold and a base mold; casting a polydimethylsiloxane mixture into the cover mold and the base mold and removing air bubbles to obtain the sensor cover and the sensor base.

[0128] Furthermore, it also includes:

[0129] The solution removal module is used to remove the solution containing copper nanoparticles on the substrate after laser etching of the conductive layer to obtain the electrode structure and before casting the polyimide solution onto the substrate.

[0130] Since the embodiments of the system part correspond to the embodiments of the method part, please refer to the description of the embodiments of the method part for the embodiments of the system part, and they will not be repeated here.

[0131] This application also provides a storage medium on which a computer program is stored, which, when executed, can perform the steps provided in the above embodiments. The storage medium may include various media capable of storing program code, such as a USB flash drive, a portable hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0132] This application also provides an electronic device that may include a memory and a processor. The memory stores a computer program, and when the processor calls the computer program in the memory, it can implement the steps provided in the above embodiments. Of course, the electronic device may also include various network interfaces, power supplies, and other components.

[0133] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple; relevant parts can be referred to the method section. It should be noted that those skilled in the art can make various improvements and modifications to this application without departing from the principles of this application, and these improvements and modifications also fall within the protection scope of this application.

[0134] It should also be noted that, in this specification, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

Claims

1. A method of manufacturing a flexible six-axis force sensor, characterized in that, The application relates to a method for preparing a flexible six-dimensional force sensor. The nylon powder is sintered through a selective laser sintering technology to obtain a mold with a preset microstructure; wherein the preset microstructure is a microstructure comprising a plurality of protruding parts and recessed parts; A polydimethylsiloxane mixture is poured into the mold to allow the polydimethylsiloxane mixture to solidify in the mold to form a polydimethylsiloxane film; wherein the polydimethylsiloxane film has the preset microstructure; A multi-walled carbon nanotube is sprayed onto the surface of the polydimethylsiloxane film with the preset microstructure to obtain a sensing unit; wherein the sensing unit is a polydimethylsiloxane film with the preset microstructure and sprayed with the multi-walled carbon nanotube; A solution containing copper nanoparticles is drop-coated onto a substrate to form a conductive layer; The conductive layer is laser etched to obtain an electrode structure; A polyimide solution is poured onto the substrate to allow the polyimide solution to solidify to form a flexible electrode film; wherein the surface of the flexible electrode film is embedded with copper nanoparticles of the conductive layer; The sensing unit and the flexible electrode film are face-to-face packaged to obtain a flexible sensing unit; wherein the surface of the sensing unit sprayed with the multi-walled carbon nanotube is in contact with the surface of the flexible electrode film embedded with copper nanoparticles; The flexible six-dimensional force sensor is prepared by using the flexible sensing unit; The method for preparing the flexible six-dimensional force sensor by using the flexible sensing unit comprises: Preparation of a sensor top cover and a sensor base; wherein the sensor top cover and the sensor base are a mortise and tenon structure with concave-convex interlocking, the sensor base comprises eight first bearing surfaces, adjacent first bearing surfaces have different attitudes, and the sensor top cover has a second bearing surface corresponding to each first bearing surface; Eight flexible sensing units are packaged between a first film and a second film to form a flexible sensing unit array; wherein the eight flexible sensing units in the flexible sensing unit array are symmetrically arranged and in the same plane, the first film is a film prepared by using polyimide, the second film is a film prepared by using polydimethylsiloxane, the flexible electrode film in the flexible sensing unit is in contact with the first film, and the sensing unit in the flexible sensing unit is in contact with the second film; The flexible sensing unit array is bent according to the shape of the sensor base, and the bent flexible sensing unit array is assembled between the sensor top cover and the sensor base to obtain the flexible six-dimensional force sensor; wherein each flexible sensing unit in the flexible six-dimensional force sensor is embedded between the corresponding first bearing surface and the second bearing surface.

2. The method of claim 1, wherein the flexible six-axis force sensor is prepared by the steps of: The preparation of the sensor top cover and the sensor base comprises: A top cover mold and a base mold are prepared by using a 3D printing device; A polydimethylsiloxane mixture is poured into the top cover mold and the base mold to remove bubbles to obtain the sensor top cover and the sensor base.

3. The method for fabricating the flexible six-dimensional force sensor according to claim 1, characterized in that, After the laser etching of the conductive layer to obtain the electrode structure, before the pouring of the polyimide solution into the substrate, the method further comprises: Removing the solution containing copper nanoparticles from the substrate.

4. A glove characterized in that, The glove body comprises: A flexible six-dimensional force sensor arranged at a predetermined position of the glove body, wherein the flexible six-dimensional force sensor is prepared according to the preparation method of the flexible six-dimensional force sensor in any one of claims 1 to 3; A signal processing module connected to the flexible sensing unit in the flexible six-dimensional force sensor through a lead, wherein the signal processing module is configured to calculate force information and / or torque information of the glove according to a resistance value of the flexible sensing unit. The signal processing module comprises a calculation unit, a voltage detection unit and a plurality of fixed resistors; 5. The glove of claim 4, wherein, Each fixed resistor is connected in series with the corresponding flexible sensing unit through the lead; The voltage detection unit is configured to detect a voltage signal across each fixed resistor; The calculation unit is configured to determine the force information and / or the torque information according to the voltage signal. The process of determining the force information and / or the torque information according to the voltage signal by the calculation unit comprises: substituting the voltage signal into a mapping matrix to obtain the force information and / or the torque information, wherein the mapping matrix is a matrix obtained through a static calibration experiment.

6. The glove of claim 5, wherein, The laser sintering module is configured to sinter nylon powder through a selective laser sintering technology to obtain a mold with a predetermined microstructure, wherein the predetermined microstructure is a microstructure comprising a plurality of protrusions and recesses.

7. A system for the preparation of a flexible six-axis force sensor, characterized by The first pouring module is configured to pour a polydimethylsiloxane mixture into the mold so that the polydimethylsiloxane mixture solidifies in the mold to form a polydimethylsiloxane film, wherein the polydimethylsiloxane film has the predetermined microstructure. The spraying module is configured to spray multi-walled carbon nanotubes to a surface of the polydimethylsiloxane film having the predetermined microstructure to obtain a sensing unit, wherein the sensing unit is a polydimethylsiloxane film having the predetermined microstructure and sprayed with the multi-walled carbon nanotubes. The electrode etching module is configured to drop a solution containing copper nanoparticles onto a substrate to form a conductive layer, and further configured to perform laser etching on the conductive layer to obtain an electrode structure. The second pouring module is configured to pour a polyimide solution onto the substrate so that the polyimide solution solidifies to form a flexible electrode film, wherein copper nanoparticles of the conductive layer are embedded in a surface of the flexible electrode film. The packaging module is configured to package the sensing unit and the flexible electrode film face-to-face to obtain a flexible sensing unit, wherein a surface of the sensing unit sprayed with the multi-walled carbon nanotubes is in contact with a surface of the flexible electrode film embedded with the copper nanoparticles. The preparation module is configured to prepare a flexible six-dimensional force sensor using the flexible sensing unit. ​ ​ The preparation module utilizes the flexible sensing unit to prepare a flexible six-dimensional force sensor, including: preparing a sensor upper cover and a sensor base; the sensor upper cover and the sensor base are a mortise and tenon structure of concave-convex interlocking, the sensor base includes eight first bearing surfaces, adjacent first bearing surfaces have different postures, and the sensor upper cover has a second bearing surface corresponding to each first bearing surface; eight flexible sensing units are encapsulated between a first film and a second film to form a flexible sensing unit array; the eight flexible sensing units in the flexible sensing unit array are symmetrically arranged and in the same plane, the first film is a film prepared from polyimide, the second film is a film prepared from polydimethylsiloxane, a flexible electrode film in the flexible sensing unit is in contact with the first film, and a sensing unit in the flexible sensing unit is in contact with the second film; the flexible sensing unit array is bent according to the shape of the sensor base, and the bent flexible sensing unit array is assembled between the sensor upper cover and the sensor base to obtain the flexible six-dimensional force sensor; and each flexible sensing unit in the flexible six-dimensional force sensor is embedded between the corresponding first bearing surface and the second bearing surface.

8. An electronic device, comprising: The memory stores a computer program, and the processor calls the computer program in the memory to realize the steps of the preparation method of the flexible six-dimensional force sensor according to any one of claims 1 to 3.

9. A storage medium, characterized by The storage medium stores computer executable instructions, and the computer executable instructions are loaded and executed by the processor to realize the steps of the preparation method of the flexible six-dimensional force sensor according to any one of claims 1 to 3.

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