Anti-damage cascading touch sensing module and sensing method thereof

Abstract

The invention belongs to the technical field of robot tactile sensing and man-machine interaction, and provides an anti-damage cascading tactile sensing module and a sensing method thereof.The anti-damage cascading tactile sensing module comprises a single-face electrode substrate, a tactile sensing interface is arranged on one side of the single-face electrode substrate and comprises a piezoresistive material layer and a plurality of electrodes, the electrodes are electrically insulated, and the piezoresistive material layer is arranged on the single-face electrode substrate. The piezoresistive material layer covers the plurality of electrodes and is electrically connected with the plurality of electrodes; the plurality of electrodes are electrically connected with the reading circuit through the electrode channels, the reading circuit is used for collecting and outputting signals sent by the plurality of electrodes, and the reading circuit is provided with a communication interface used for being in cascade connection with another reading circuit. The method does not depend on the overall body resistance change of a conductive material, the tactile function can still be kept after the material is cut or locally damaged, meanwhile, module cascade expansion is supported, and the engineering application requirement of a robot tactile system can be met.

Description

Technical Field

[0001] This invention belongs to the field of robot tactile perception and human-computer interaction technology, and particularly relates to a damage-resistant cascaded tactile sensing module and its sensing method. Background Technology

[0002] As robots are increasingly used in service, collaborative manufacturing, and human-computer interaction, their real-time perception of external contact states has become a crucial foundation for ensuring safe operation and enhancing intelligence. The tactile sensing module, as the basic unit for building a robot's tactile skin, significantly impacts the engineering application of the entire tactile system due to its stability, maintainability, and scalability.

[0003] In existing flexible tactile or pressure sensing solutions, one type of solution achieves tactile sensing by utilizing the change in the overall volume resistance of a conductive material with the force applied. This type of solution can output a stable signal when the material structure is intact, but when the material is cut, damaged, or partially destroyed, the overall equivalent resistance network is altered, which can easily lead to zero-point drift, sensitivity changes, or even signal failure. This usually requires the entire sensing module to be replaced or recalibrated, resulting in high maintenance costs and hindering the long-term operation of the robot.

[0004] Furthermore, in applications requiring full-body tactile coverage for robots, the tactile module typically needs to support multi-module cascading expansion to reduce wiring complexity and improve system deployment flexibility. However, some existing tactile modules still have shortcomings in terms of damage resistance and cascading expansion capabilities. Summary of the Invention

[0005] The purpose of this invention is to provide a damage-resistant, cascaded tactile sensing module and its sensing method to solve the above-mentioned problems, achieve tactile function without relying on changes in the overall volume resistance of conductive materials, and maintain tactile function even after the material is cut or partially damaged. At the same time, it supports module cascading expansion to meet the engineering application requirements of robot tactile systems.

[0006] To achieve the above objectives, the present invention provides the following solution: a damage-resistant cascadeable tactile sensing module, comprising: A single-sided electrode substrate, wherein a tactile sensing interface is provided on one side of the single-sided electrode substrate, the tactile sensing interface includes a piezoresistive material layer and multiple electrodes, the multiple electrodes are electrically insulated from each other, and the piezoresistive material layer covers the multiple electrodes and is electrically connected to the multiple electrodes; A reading circuit is provided, wherein multiple electrodes are electrically connected to the reading circuit through an electrode channel. The reading circuit is used to collect and output signals emitted by the multiple electrodes. The reading circuit is provided with a communication interface for cascading with another reading circuit.

[0007] Preferably, the single-sided electrode substrate includes a flexible substrate, and the plurality of electrodes are disposed on the same side of the flexible substrate.

[0008] Preferably, the plurality of electrodes include at least one set of central electrodes and a plurality of discrete electrodes, the central electrodes being located in the middle of the flexible substrate, the plurality of discrete electrodes being spaced apart on the edge of the flexible substrate, and the central electrodes and the plurality of discrete electrodes being electrically insulated from each other.

[0009] Preferably, a spacer layer is provided between the central electrode and the piezoresistive material layer, the spacer layer being used to define an initial distance between the piezoresistive material layer and the central electrode.

[0010] Preferably, the spacer layer adopts a mesh structure or a dot matrix structure.

[0011] Preferably, a second conductive connection point is provided in the middle of the central electrode, and the central electrode is electrically connected to the piezoresistive material layer through the second conductive connection point. A first conductive connection point is provided on each of the plurality of discrete electrodes, and the discrete electrodes are electrically connected through the first conductive connection point.

[0012] Preferably, the electrode channel includes a central electrode channel and multiple discrete electrode channels. The central electrode is electrically connected to one end of the central electrode channel, and the multiple discrete electrodes are respectively electrically connected to one end of the multiple discrete electrode channels. The other end of the central electrode channel and the central electrode is electrically connected to the reading circuit.

[0013] Preferably, the reading circuit is further provided with a signal interface, which is electrically connected to the central electrode channel and the discrete electrode channel.

[0014] Preferably, the piezoresistive material layer is made of a conductive flexible material.

[0015] A sensing method for a damage-resistant cascadeable tactile sensing module includes the following steps: When the piezoresistive material layer undergoes local deformation under external pressure, the actual contact area and contact state between the piezoresistive material layer and the corresponding electrode change, causing a change in the interfacial contact resistance. The reading circuit collects the contact resistance change signals of each electrode, and determines the location and pressure of the external pressure based on the contact resistance change signals of each electrode. If the piezoresistive material layer is partially cut or damaged, only the signal between the electrode corresponding to the damaged area and the reading circuit will be abnormal. The reading circuit can still collect the contact resistance change signal of the electrode in the undamaged area.

[0016] Compared with the prior art, the present invention has the following advantages and technical effects: 1. This invention uses the change in interfacial contact resistance between the electrode and the conductive flexible material as the main sensing mechanism. The tactile signal mainly comes from the change in contact resistance between the electrode and the conductive flexible material, rather than the change in the overall resistance of the non-conductive material. By utilizing the differences in signals from multiple electrode channels, the pressing position and pressing force can be detected, reducing the dependence on the change in the overall resistance of the conductive material.

[0017] 2. Multiple tactile sensing modules can be cascaded and expanded through communication interfaces, reducing system wiring complexity and making it suitable for building large-area robotic tactile skin.

[0018] 3. The tactile sensing module of the present invention can still maintain tactile output after the conductive material is cut or partially damaged, and supports the cascading deployment of multiple modules via a bus to realize the detection of pressing position and pressing force, providing a module-level implementation method with engineering robustness and scalability. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the structure of the tactile sensing module of the present invention; Figure 2 This is a schematic diagram of the single-sided electrode substrate and electrode distribution of the present invention; Figure 3 This is a schematic diagram of the spacer layer of the present invention; Figure 4 This is a schematic diagram of the first conductive connection point and the second conductive connection point of the present invention; Figure 5 This is a schematic diagram of the cascading of multiple tactile sensing modules in this invention; Figure 6 This is a schematic diagram of a partial damaged state of the tactile sensing module of the present invention; Among them, 1. Single-sided electrode substrate; 101. Discrete electrode; 102. Center electrode; 103. Flexible substrate; 2. Spacer layer; 3. Piezoresistive material layer; 4. Readout circuit; 104. Discrete electrode channel; 105. Center electrode channel; 301. First conductive connection point; 302. Second conductive connection point; 401. Communication interface; 402. Signal interface; 403. Communication bus. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] Reference Figures 1-6 This invention provides a damage-resistant, cascadeable tactile sensing module, comprising: A single-sided electrode substrate 1 is provided on one side of the single-sided electrode substrate 1. The tactile sensing interface includes a piezoresistive material layer 3 and multiple electrodes. The multiple electrodes are electrically insulated from each other. The piezoresistive material layer 3 covers the multiple electrodes and is electrically connected to the multiple electrodes. The reading circuit 4 has multiple electrodes electrically connected to it through an electrode channel. The reading circuit 4 is used to collect and output signals emitted by the multiple electrodes. The reading circuit 4 is equipped with a communication interface 401 for cascading with another reading circuit 4.

[0024] Multiple electrodes are electrically connected to the piezoresistive material layer 3. When the piezoresistive material layer 3 is deformed under force, the actual contact area and contact state between the piezoresistive material layer 3 and the corresponding electrode change, causing a change in the interface contact resistance. This avoids the problem of traditional sensing modules relying on the overall resistance change of the piezoresistive material layer. Therefore, when the piezoresistive material layer of the present invention is cut, removed, or partially damaged, only the contact interface corresponding to the damaged area is affected. As long as the undamaged area still forms an effective contact interface with the corresponding electrode, a stable tactile signal can still be output. The main function of the reading circuit 4 is to collect and output the signals emitted by each electrode. The main function of the communication interface 401 on the reading circuit 4 is to realize the cascading expansion of multiple tactile sensing modules, which helps to reduce the complexity of system wiring.

[0025] Further optimization of the scheme allows for the cascading connection of communication interfaces 401 on multiple reading circuits 4 via a communication bus 403. Multi-module data acquisition can be achieved through address allocation or polling, thereby constructing a large-area tactile sensing system and enabling module-level expansion deployment. The communication bus 403 can use an RS485 bus. In a further optimized design, the single-sided electrode substrate 1 includes a flexible substrate 103, with multiple electrodes disposed on the same side of the flexible substrate 103.

[0026] In this embodiment, the single-sided electrode substrate 1 is a conductive electrode structure on an insulating flexible substrate, preferably a polygonal flexible printed circuit board. The shape of the single-sided electrode substrate 1 can be triangular, quadrilateral, pentagonal, hexagonal, or other polygonal forms.

[0027] In a further optimized scheme, the multiple electrodes include at least one set of central electrodes 102 and multiple discrete electrodes 101. The central electrodes 102 are located in the middle of the flexible substrate 103, and the multiple discrete electrodes 101 are distributed at intervals on the edge of the flexible substrate 103. The central electrodes 102 and the multiple discrete electrodes 101 are printed on the flexible substrate 103 and are electrically insulated from each other.

[0028] In this embodiment, the flexible substrate 103 is configured as a regular hexagon, and six discrete electrodes 101 are circular and arranged in parallel, distributed at the six corners of the flexible substrate 103. The central electrode 102 is a large-area electrode located in the middle, forming a seven-way electrode lead structure. Figure 2 As shown, the electrode layout does not form a regular array structure, but rather achieves tactile signal acquisition through a small number of discrete electrodes 101, thereby reducing the number of electrodes and wiring complexity. When different pressures are applied to the piezoresistive material layer 3 at different locations, the contact state between the central electrode 102, the multiple discrete electrodes 101, and the piezoresistive material layer 3 changes to different degrees, resulting in differences in the amplitude of contact resistance changes corresponding to each electrode channel, thus providing a basis for distinguishing the pressing position and pressure.

[0029] In a further optimized design, a spacer layer 2 is provided between the central electrode 102 and the piezoresistive material layer 3. The spacer layer 2 is used to define the initial distance between the piezoresistive material layer 3 and the central electrode 102.

[0030] like Figure 1 , Figure 4 As shown, in this embodiment, the spacer layer 2 is disposed between the central electrode 102 and the piezoresistive material layer 3 to define the initial spacing or initial contact state between the piezoresistive material layer 3 and the central electrode 102. The spacer layer 2 only covers the area corresponding to the central electrode 102, and no spacer layer is disposed in the surrounding discrete electrode 101 area.

[0031] like Figure 3 As shown, the flexible substrate 103 has a rectangular structure, with discrete electrodes 101 located at the four corners. The spacer layer 2 is only located in the area corresponding to the central electrode 102, and there is no spacer layer 2 at the discrete electrode 101.

[0032] To further optimize the design, the second interlayer adopts a grid structure or a dot matrix structure.

[0033] like Figure 1As shown, in this embodiment, the spacer layer 2 is a mesh structure or a dot matrix structure, which can be formed by 3D printing to form a mesh skeleton, or by applying UV-curable adhesive through a dispensing device and curing it.

[0034] The further optimized scheme includes a central electrode channel 105 and multiple discrete electrode channels 104. The central electrode 102 is electrically connected to one end of the central electrode channel 105, and the multiple discrete electrodes 101 are electrically connected to one end of the multiple discrete electrode channels 104 respectively. The other ends of the central electrode channel 105 and the central electrode 102 are electrically connected to the reading circuit 4.

[0035] The scheme is further optimized by setting the spacer layer 2 only in the central electrode 102 area, so that the central electrode channel 105 maintains a stable contact resistance baseline when no external force is applied, thereby improving the stability of the overall signal.

[0036] In a further optimized design, a second conductive connection point 302 is provided in the middle of the central electrode 102. The central electrode 102 is electrically connected to the piezoresistive material layer 3 through the second conductive connection point 302. A first conductive connection point 301 is provided on each of the multiple discrete electrodes 101. The discrete electrodes 101 are electrically connected through the first conductive connection point 301.

[0037] like Figure 4 As shown, in this embodiment, the main function of the first conductive connection point 301 and the second conductive connection point 302 is to establish stable conductive contact boundary conditions between the piezoresistive material layer 3 and the central electrode 102 and the discrete electrode 101 in the absence of external force.

[0038] In a further optimized design, the first conductive connection point 301 and the second conductive connection point 302 are bonded together by conductive materials, including but not limited to silver paste, conductive adhesive, or other conductive adhesive materials.

[0039] In a further optimization, the first conductive connection point 301 and the second conductive connection point 302 can also be configured as mechanical conductive connection structures, including but not limited to conductive rivets, conductive pillars, or other mechanical connectors that can achieve electrical connection.

[0040] Through the first conductive connection point 301 and the second conductive connection point 302, the piezoresistive material layer 3 can still form a stable conductive contact boundary condition with the discrete electrode 101 and the central electrode 102 in the absence of external force, avoiding accidental virtual contact caused by material springback, slight displacement or assembly error, thereby improving the consistency and repeatability of the reading signals of each electrode channel.

[0041] To further optimize the scheme, the reading circuit 4 is also equipped with a signal interface 402, which is electrically connected to the central electrode channel 105 and the discrete electrode channel 104.

[0042] The reading circuit 4 is used to acquire electrical signals reflecting the changes in the interfacial contact resistance between each electrode and the piezoresistive material layer 3, and converts the signals into digital tactile data output. The communication interface 401 on the reading circuit 4 is an RS485 communication interface, and the signal interface 402 is a sensor signal interface, used to connect with each electrode.

[0043] To further optimize the design, conductive flexible material was selected for the piezoresistive material layer 3.

[0044] In this embodiment, the piezoresistive material layer 3 includes, but is not limited to, conductive porous elastic materials, conductive sponges, conductive rubber, conductive silicone, or conductive TPU. When external pressure is applied to the piezoresistive material layer, the pressure-bearing portion of the piezoresistive material layer undergoes localized deformation, causing a change in its actual contact area with the underlying electrode substrate, thereby resulting in a change in the interfacial contact resistance.

[0045] A sensing method for a damage-resistant cascadeable tactile sensing module includes the following steps: When the piezoresistive material layer 3 is subjected to external pressure and undergoes local deformation, the actual contact area and contact state between the piezoresistive material layer 3 and the corresponding electrode change, causing a change in the interface contact resistance. The reading circuit 4 collects the contact resistance change signals of each electrode and determines the location and pressure of the external pressure based on the contact resistance change signals of each electrode. If the piezoresistive material layer 3 is partially cut or damaged, only the signal between the electrode corresponding to the damaged area and the reading circuit 4 will be abnormal. The reading circuit 4 can still collect the contact resistance change signal of the electrode in the undamaged area.

[0046] In this embodiment, when no external force is applied, the piezoresistive material layer 3, under the combined action of the spacer layer 2 and the first conductive connection point 301 and the second conductive connection point 302, forms a stable initial contact state with the discrete electrode 101 and the center electrode 102. The center electrode channel 105 and the discrete electrode channel 104 output stable baseline signals. When external pressure is applied to different positions of the piezoresistive material layer 3, the piezoresistive material layer 3 undergoes local compression, and the actual contact area and contact pressure between it and the corresponding electrode change, thereby causing a change in the interface contact resistance. Due to the different spatial distribution of the electrodes, the amplitude of the contact resistance change corresponding to each electrode channel is different. The reading circuit 4 can output the pressing position and pressing force information based on the amplitude, difference, or ratio characteristics of the signals of each center electrode channel 105 or discrete electrode channel 104.

[0047] like Figure 6As shown, when the piezoresistive material layer 3 is cut, removed, or damaged in a local area A, only the interface contact relationship between the electrode corresponding to the damaged area A and the piezoresistive material layer 3 changes. The undamaged area B still forms an effective contact interface with the corresponding electrode, so the corresponding electrode channel can still output a stable tactile signal.

[0048] Since the tactile signals of this invention mainly originate from the changes in the interfacial contact resistance between each electrode and the piezoresistive material layer 3, and do not depend on the changes in the overall bulk resistance of the piezoresistive material layer 3, the continuity of the overall conductive network of the material is not a necessary condition for the formation of tactile signals. Therefore, when the piezoresistive material layer 3 is locally damaged, only the local interfacial contact is affected, and the tactile sensing function of other areas is not significantly interfered with. There is no need to replace or recalibrate the entire tactile sensing module, thereby significantly improving the module's damage resistance, reliability, and maintainability.

[0049] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0050] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A damage-resistant, cascadeable tactile sensing module, characterized in that, include: A single-sided electrode substrate (1) is provided with a tactile sensing interface on one side. The tactile sensing interface includes a piezoresistive material layer (3) and multiple electrodes. The multiple electrodes are electrically insulated from each other. The piezoresistive material layer (3) covers the multiple electrodes and is electrically connected to the multiple electrodes. The reading circuit (4) is provided with multiple electrodes electrically connected to the reading circuit (4) through an electrode channel. The reading circuit (4) is used to collect and output signals emitted by the multiple electrodes. The reading circuit (4) is provided with a communication interface (401) for cascading with another reading circuit (4).

2. The damage-resistant cascadeable tactile sensing module according to claim 1, characterized in that: The single-sided electrode substrate (1) includes a flexible substrate (103), and a plurality of electrodes are disposed on the same side of the flexible substrate (103).

3. The damage-resistant cascadeable tactile sensing module according to claim 2, characterized in that: The plurality of electrodes include at least one set of central electrodes (102) and a plurality of discrete electrodes (101). The central electrodes (102) are located in the middle of the flexible substrate (103), and the plurality of discrete electrodes (101) are distributed at intervals on the edge of the flexible substrate (103). The central electrodes (102) and the plurality of discrete electrodes (101) are electrically insulated from each other.

4. The damage-resistant cascadeable tactile sensing module according to claim 3, characterized in that: A spacer layer (2) is provided between the central electrode (102) and the piezoresistive material layer (3), the spacer layer (2) being used to define the initial distance between the piezoresistive material layer (3) and the central electrode (102).

5. The damage-resistant cascadeable tactile sensing module according to claim 4, characterized in that: The spacer layer (2) adopts a grid structure or a dot matrix structure.

6. The damage-resistant cascadeable tactile sensing module according to claim 3, characterized in that: The center electrode (102) is provided with a second conductive connection point (302) in the middle. The center electrode (102) is electrically connected to the piezoresistive material layer (3) through the second conductive connection point (302). The discrete electrodes (101) are respectively provided with a first conductive connection point (301). The discrete electrodes (101) are electrically connected through the first conductive connection point (301).

7. The damage-resistant cascadeable tactile sensing module according to claim 3, characterized in that: The electrode channel includes a central electrode channel (105) and multiple discrete electrode channels (104). The central electrode (102) is electrically connected to one end of the central electrode channel (105), and the multiple discrete electrodes (101) are electrically connected to one end of the multiple discrete electrode channels (104). The other ends of the central electrode channel (105) and the central electrode (102) are electrically connected to the reading circuit (4).

8. The damage-resistant cascadeable tactile sensing module according to claim 7, characterized in that: The reading circuit (4) is also provided with a signal interface (402), which is electrically connected to the central electrode channel (105) and the discrete electrode channel (104).

9. The damage-resistant cascadeable tactile sensing module according to claim 1, characterized in that: The piezoresistive material layer (3) is made of a conductive flexible material.

10. A sensing method for a damage-resistant cascadeable tactile sensing module, based on the damage-resistant cascadeable tactile sensing module according to claim 1, characterized in that, Includes the following steps: When the piezoresistive material layer (3) is subjected to external pressure and undergoes local deformation, the actual contact area and contact state between the piezoresistive material layer (3) and the corresponding electrode change, causing a change in the interface contact resistance. The reading circuit (4) collects the contact resistance change signal of each electrode and determines the position and pressure of the external pressure based on the contact resistance change signal of each electrode. If the piezoresistive material layer (3) is partially cut or damaged, the signal between the electrode corresponding to the damaged area and the reading circuit (4) will be abnormal. The reading circuit (4) can still collect the contact resistance change signal of the electrode in the undamaged area.

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