Capacitive tactile sensor, capacitive tactile sensor array, method and apparatus for determining mechanical information

Abstract

The embodiment of the present specification provides a capacitive tactile sensor, a capacitive tactile sensor array, a mechanical information determination method and equipment, wherein the capacitive tactile sensor comprises: a common layer and a detection layer which are arranged separately, the detection layer comprises a first detection electrode group, a second detection electrode group and a third detection electrode group; the first detection electrode group and the common layer constitute a first detection unit for detecting a tangential force; the second detection electrode group and the common layer constitute a second detection unit for detecting a vertical axial pressure and a torque around a horizontal axis; and the third detection electrode group and the common layer constitute a third detection unit for detecting a torque around a vertical axis. Not only the difficulty and cost of the preparation process are greatly reduced, but also the robot can be endowed with six-degree-of-freedom tactile perception ability.

Description

Technical Field

[0001] The embodiments in this specification relate to the field of sensor technology, and in particular to capacitive tactile sensors, capacitive tactile sensor arrays, methods and devices for determining mechanical information. Background Technology

[0002] Tactile sensing is a key technology that gives robots the ability to perceive "tactile sensation," enabling them to sense pressure and object state like humans, thereby achieving precise grasping and safe human-robot interaction. With the development of intelligent manufacturing and humanoid robots, tactile sensors with high sensitivity and multi-dimensional perception capabilities have become a core requirement for improving the operational flexibility of robots.

[0003] However, most mainstream tactile sensors can only detect a single normal force (i.e., vertical axial pressure), which makes it impossible for robots to determine whether an object is sliding or to make fine angle adjustments. In addition, these tactile sensors often rely on fragile microstructures to improve sensitivity, which limits their reliability and practicality in long-term, dynamic industrial scenarios. Summary of the Invention

[0004] In view of this, embodiments of this specification provide a capacitive tactile sensor. One or more embodiments of this specification also relate to a capacitive tactile sensing array, a method for determining mechanical information, and a device with tactile sensing functionality, to address the technical deficiencies existing in the prior art.

[0005] According to a first aspect of the embodiments of this specification, a capacitive tactile sensor is provided, including a common layer and a detection layer disposed in isolation, wherein the detection layer includes a first detection electrode group, a second detection electrode group and a third detection electrode group; The first detection electrode group and the common layer constitute the first detection unit for detecting tangential force; The second detection electrode group and the common layer constitute a second detection unit for detecting vertical axial pressure and torque about the horizontal axis. The third detection electrode group and the common layer constitute the third detection unit for detecting torque about the vertical axis.

[0006] According to a second aspect of the embodiments of this specification, a capacitive tactile sensing array is provided, including a plurality of capacitive tactile sensors.

[0007] According to a third aspect of the embodiments of this specification, a method for determining mechanical information is provided, applied to a capacitive tactile sensor; comprising: The first capacitance differential mode signal of the first detection unit in the capacitive tactile sensor is acquired, and the tangential force is determined based on the first capacitance differential mode signal; The common-mode signal and differential-mode signal of the second detection unit in the capacitive tactile sensor are collected. The vertical axial pressure is determined based on the common-mode signal, and the torque around the horizontal axis is determined based on the differential-mode signal. The third capacitance differential mode signal of the third detection unit in the capacitive tactile sensor is acquired, and the torque about the vertical axis is determined based on the third capacitance differential mode signal. The tangential force includes a first tangential force along a first horizontal direction and a second tangential force along a second horizontal direction; the moment about the horizontal axis includes a first moment about the horizontal axis about the first horizontal direction and a second moment about the horizontal axis about the second horizontal direction. Determining the tangential force based on the differential mode signal of the first capacitor includes: The initial first tangential force and the initial second tangential force are determined based on the differential mode signal of the first capacitor; The first tangential force is determined based on the initial first tangential force and the first moment about the horizontal axis; The second tangential force is determined based on the initial second tangential force and the second torque about the horizontal axis.

[0008] According to a fourth aspect of the embodiments of this specification, a device with tactile sensing function is provided, including a capacitive tactile sensing array.

[0009] The capacitive tactile sensor provided in one embodiment of this specification firstly achieves full-dimensional coverage of mechanical perception from a physical structure perspective. It utilizes a first detection unit, a second detection unit, and a third detection unit to accurately respond to tangential slip, normal contact, and torsional torque, respectively, overcoming the limitation of traditional sensors that can only measure a single normal force. Secondly, by leveraging the response characteristics of each detection unit to different tactile modes, it effectively suppresses cross-coupling interference between multiple degrees of freedom, significantly improving the accuracy of decoupling mechanical components under complex force conditions. Furthermore, this capacitive tactile sensor abandons dependence on microstructures, instead detecting capacitance changes through a planar electrode layout. This not only significantly reduces the difficulty and cost of the manufacturing process but also eliminates the performance drift risk caused by microstructure fatigue. Thus, it endows robots with six-degree-of-freedom tactile perception capabilities that are highly reliable, easily mass-producible, and capable of handling complex unstructured tasks such as precision assembly and flexible grasping. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the structure of a first capacitive tactile sensor provided in one embodiment of this specification; Figure 2 This is a schematic diagram of the structure of a detection layer provided in one embodiment of this specification; Figure 3 This is a schematic diagram of the structure of a second capacitive tactile sensor provided in one embodiment of this specification; Figure 4This is a schematic diagram of a common layer structure provided in one embodiment of this specification; Figure 5 This is a schematic diagram illustrating the positional relationship between a common layer and a detection layer according to one embodiment of this specification; Figure 6 This is a schematic diagram of the structure of a third type of capacitive tactile sensor provided in one embodiment of this specification; Figure 7 This is a schematic diagram of the structure of a capacitive tactile sensing array provided in one embodiment of this specification; Figure 8 This is a schematic diagram of the connection relationship of a capacitive tactile sensor provided in one embodiment of this specification; Figure 9 This is a schematic diagram of another capacitive tactile sensor connection provided in one embodiment of this specification; Figure 10 This is a flowchart illustrating a method for determining mechanical information according to one embodiment of this specification; Figure 11 This is a schematic diagram of the structure of a device with tactile sensing function provided in one embodiment of this specification. Detailed Implementation

[0011] Many specific details are set forth in the following description to provide a full understanding of this specification. However, this specification can be implemented in many other ways than those described herein, and those skilled in the art can make similar extensions without departing from the spirit of this specification. Therefore, this specification is not limited to the specific implementations disclosed below.

[0012] The terminology used in one or more embodiments of this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of one or more embodiments of this specification. The singular forms “a,” “described,” and “the” as used in one or more embodiments of this specification and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used in one or more embodiments of this specification refers to and includes any or all possible combinations of one or more associated listed items. The term “at least one” as used in one or more embodiments of this specification means “one or more,” and “a plurality of” means “two or more.” The term “comprising” is an open-ended description and should be understood as “including but not limiting,” and may include other content in addition to what has been described.

[0013] It should be understood that although the terms first, second, etc., may be used to describe various information in one or more embodiments of this specification, such information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, first may also be referred to as second without departing from the scope of one or more embodiments of this specification, and similarly, second may also be referred to as first. Depending on the context, the word "if" as used herein may be interpreted as "when," "when," or "in response to a determination."

[0014] First, the terms and concepts used in one or more embodiments of this specification will be explained.

[0015] Microstructures refer to arrays of micron-scale geometric shapes (such as micro pyramids, micro domes, micro pillars, or interlocking grids) built on the surface of a flexible dielectric layer. Their core function is to amplify the rate of change of capacitance or resistance signals through controllable deformation under stress (such as nonlinear increase of the contact area at the tip or gradual closure of the structure), thereby endowing the sensor with high sensitivity and wide dynamic range.

[0016] Six degrees of freedom: In the context of tactile sensors, six degrees of freedom refers to the ability of a tactile sensor to simultaneously and independently detect forces and torques in three directions at a point of contact.

[0017] Force is a direct linear interaction between objects, manifested as a tendency to push, pull, or press. It attempts to change the translational motion of an object (i.e., to make the object move in the X, Y, and Z directions). In tactile perception, it corresponds to the pressure felt and the frictional resistance generated when the object slides.

[0018] Torque / Moment: is the rotational effect of a force on an object. It is determined by the magnitude of the force and its distance from the center of rotation (lever arm). It manifests as a tendency to twist, turn, or flip. It attempts to change the rotational motion of an object (i.e., to make the object deflect at an angle around the X, Y, and Z axes). In tactile perception, it corresponds to the feeling of tilting and instability when operating an object or the torsional resistance when twisting a bottle cap.

[0019] Tactile sensing, as a core sensing means for robots or intelligent devices to achieve refined human-computer interaction and perform complex unstructured tasks, essentially transforms multi-dimensional physical quantities such as pressure, tangential force, vibration, and temperature during contact into processable electrical signals by mimicking the sensing mechanism of human skin. This endows robots or intelligent devices with the ability to perceive object properties (such as hardness and texture) and real-time interactive states (such as sliding and gripping stability).

[0020] However, the current development of tactile sensing technology is still constrained by three key bottlenecks: First, limited measurement degrees of freedom: Traditional sensors are mostly limited to the detection of a single normal force, making it difficult to simultaneously and accurately acquire tangential force and torque information in three-dimensional space. This results in robots lacking sufficient multi-dimensional mechanical feedback when facing complex operations requiring precise force control (such as grasping flexible objects and precision assembly). Second, difficulty in decoupling between different degrees of freedom: Due to the significant cross-coupling effect of sensitive materials or microstructures under stress and deformation, mechanical input in one direction often causes interference from signals in other directions. This makes it extremely challenging to accurately separate independent mechanical components from mixed signals, seriously affecting the accuracy of measurement and the stability of the control system. Finally, complex material microstructures: Microstructures designed to achieve high sensitivity and multi-dimensional sensing capabilities are not only cumbersome to manufacture, have poor mass production consistency, and are expensive, but also often experience performance drift due to fatigue and plastic deformation under long-term mechanical loads, restricting the reliability and popularization of tactile sensors in applications.

[0021] This specification provides an embodiment of a capacitive tactile sensor, including a common layer and a detection layer disposed separately. The detection layer includes a first detection electrode group, a second detection electrode group, and a third detection electrode group. The first detection electrode group and the common layer constitute a first detection unit for detecting tangential force. The second detection electrode group and the common layer constitute a second detection unit for detecting vertical axial pressure and torque about a horizontal axis. The third detection electrode group and the common layer constitute a third detection unit for detecting torque about a vertical axis.

[0022] It is worth noting that the capacitive tactile sensor proposed in the embodiments of this specification has advantages such as good dynamic response based on detecting changes in capacitance. On this basis, it can simultaneously and independently measure the force or torque of six degrees of freedom. Through the sensor structure design, the pressure, tangential force, and torque signals of different degrees of freedom are highly decoupled, which greatly reduces the difficulty of decoupling multi-degree-of-freedom measurement algorithms. At the same time, the structure is relatively simple, which reduces the difficulty of manufacturing process and production cost, which is conducive to realizing large-area tactile sensing with high spatial resolution and facilitates the fabrication of sensor arrays.

[0023] This specification provides a capacitive tactile sensor, and also relates to a capacitive tactile sensor array, a method for determining mechanical information, and a device with tactile sensing function, which will be described in detail in the following embodiments.

[0024] See Figure 1 , Figure 1 This specification shows a schematic diagram of the structure of a first capacitive tactile sensor according to an embodiment of the present specification. The capacitive tactile sensor includes a common layer and a detection layer that are isolated from each other. The detection layer includes a first detection electrode group, a second detection electrode group and a third detection electrode group. The first detection electrode group and the common layer constitute the first detection unit for detecting tangential force; The second detection electrode group and the common layer constitute a second detection unit for detecting vertical axial pressure and torque about the horizontal axis. The third detection electrode group and the common layer constitute the third detection unit for detecting torque about the vertical axis.

[0025] It's important to note that capacitive tactile sensors are flexible sensors that operate based on the principle of parallel-plate capacitors. They detect external mechanical forces (such as pressure, tangential force, and torque) that cause deformation of the sensor's internal structure, resulting in a change in capacitance. This capacitance change is then converted into an electrical signal to quantify the magnitude and direction of the perceived contact force. Capacitive tactile sensors not only endow robots or intelligent devices with tactile perception capabilities, enabling them to monitor grasping forces and prevent damage to fragile objects (such as eggs and glass), but also allow them to sense vertical axial pressure, sliding (tangential force), and rotation (torque), achieving precise manipulation. Compared to resistive sensors, capacitive tactile sensors offer advantages such as low power consumption, fast response speed, less susceptibility to temperature variations, and ease of fabrication into large-area tactile sensor arrays.

[0026] The core working principle of a capacitive tactile sensor follows the formula C=εA / d, where C is capacitance, ε is dielectric constant, A is the overlap area of ​​the electrodes, and d is the electrode spacing. When a capacitive tactile sensor is subjected to vertical axial pressure, the distance d between the common layer and the detection layer inside the sensor decreases, and the capacitance value increases significantly. When the capacitive tactile sensor is subjected to tangential force (friction / sliding) or torsional force, the effective overlap area between the common layer and the detection layer changes (usually decreasing or undergoing an asymmetrical change), thereby causing a specific change in the capacitance value. By capturing these minute capacitance changes through a measurement circuit, six-dimensional force information can be determined.

[0027] In practical applications, a flexible dielectric layer can be used to isolate the common layer and the detection layer, with the common layer and detection layer respectively located on opposite sides of the flexible dielectric layer. The flexible dielectric layer is an insulating elastic material layer, typically made of composite flexible materials, multilayer dielectrics, silicone, polyurethane, or foamed rubber. The structure of the flexible dielectric layer can be an array of prisms or frustums. When subjected to pressure or tangential force, the flexible dielectric layer undergoes compression or shear deformation, leading to changes in the distance between electrodes or the effective overlap area, thereby causing capacitance changes.

[0028] The common layer refers to a conductive layer used to provide a unified potential reference surface, simplifying circuit design, and forming three independent capacitors with three different detection electrode groups (first detection electrode group, second detection electrode group, and third detection electrode group).

[0029] The detection layer is a patterned conductive layer containing three independently designed sets of detection electrodes. The detection layer uses photolithography or printing processes to create a specific shape and geometric arrangement of conductive material, forming three different sets of detection electrodes. This converts mechanical deformation in different directions into specific capacitance signal changes. The detection layer can also be called a six-degree-of-freedom detection electrode layer.

[0030] The first detection electrode group refers to the array of electrodes located in the detection layer, used to respond to horizontal tangential forces. It is typically arranged in a cross-shaped or circular pattern around the sensor's center point. The capacitor formed by the first detection electrode group and the common layer is primarily sensitive to changes in the effective overlap area between the electrodes, and relatively insensitive to changes in spacing (or the effect of spacing is offset by structural design). When the tactile sensor is subjected to a horizontal tangential force, the flexible dielectric layer undergoes shear deformation, causing a horizontal displacement between the first detection electrode group and the common layer. This displacement alters their overlap area, resulting in a significant change in capacitance.

[0031] The second detection electrode group refers to the electrode array located in the detection layer, used to respond to vertical axial pressure and torque about the horizontal axis. It is typically distributed in a cross-shaped or circular pattern around the sensor's center point. The capacitor formed by the second detection electrode group and the common layer is highly sensitive to changes in the electrode spacing. When the tactile sensor is subjected to vertical downward pressure, the flexible dielectric layer is uniformly compressed, the electrode spacing decreases, and the overall capacitance increases. When the tactile sensor is subjected to a tilting torque (e.g., a larger force on one end and a smaller force on the other), the flexible dielectric layer undergoes uneven compression. The tilt angle and the magnitude and direction of the torque can be calculated by comparing the difference in capacitance changes (differential mode signal) between different regions of the electrodes.

[0032] The third detection electrode group refers to the array of electrodes located in the detection layer, used to respond to torque about the vertical axis. It is typically distributed symmetrically around the sensor's center point or at the vertices of a rectangle. When an object rotates on the sensor's contact surface (such as when unscrewing a bottle cap), the flexible dielectric layer undergoes torsional deformation. This causes an angular misalignment of the third detection electrode group relative to the common layer. This angular displacement alters the effective overlap area between the electrodes, thereby generating a capacitance signal proportional to the rotational torque.

[0033] The first detection unit, also known as the tangential force detection unit, is used to sense tangential forces parallel to the sensor contact surface.

[0034] The second detection unit, also known as the vertical axial pressure and horizontal axis torque detection unit, is used to sense the pressure (normal force) perpendicular to the sensor contact surface and the tilting torque around the horizontal axis, thereby measuring the gripping force and whether the object tilts forward, backward, or left or right.

[0035] The third detection unit, also known as the torque detection unit around the vertical axis, is used to sense the torque (torsional force) of rotation around an axis perpendicular to the sensor contact surface, thereby detecting the rotational motion or twisting force of the object and realizing precise screwing operations.

[0036] Tangential force refers to the force acting on the sensor contact surface and parallel to that surface, including a first tangential force (which can be denoted as "Fx") and a second tangential force (which can be denoted as "Fy"). In capacitive tactile sensors, tangential force can cause changes in the effective overlap area between the common layer and the detection layer (while the spacing remains essentially unchanged).

[0037] Vertical axial pressure refers to the force acting on the sensor contact surface, perpendicular to that surface, and can be denoted as "Fz". In capacitive tactile sensors, vertical axial pressure can cause vertical compression or stretching deformation of the flexible dielectric layer inside the sensor, which in turn causes a change in the spacing between the common layer and the detection layer (while the effective overlap area remains basically unchanged).

[0038] The torque about the horizontal axis refers to the torque that causes an object to tilt or flip about the horizontal axis (X-axis or Y-axis), including the first torque about the horizontal axis (which can be denoted as "My") and the second torque about the horizontal axis (which can be denoted as "Mx"). In capacitive tactile sensors, the torque about the horizontal axis can cause the distance between the electrodes on one side of the sensor to decrease and the distance between the electrodes on the other side to increase (differential change).

[0039] The torque about the vertical axis is the torque that causes an object to rotate or twist about the vertical axis (Z-axis), and can be denoted as "Mz". In capacitive tactile sensors, the torque about the vertical axis can cause tangential relative displacement between the electrodes inside the sensor.

[0040] The solution implemented in this specification first achieves full-dimensional coverage of mechanical perception from a physical structure perspective. The first, second, and third detection units accurately respond to tangential slip, normal contact, and torsional torque, respectively, overcoming the limitation of traditional sensors that can only measure a single normal force. Secondly, by leveraging the response characteristics of each detection unit to different tactile modes, cross-coupling interference between multiple degrees of freedom is effectively suppressed, significantly improving the accuracy of decoupling mechanical components under complex force conditions. Furthermore, this capacitive tactile sensor abandons reliance on microstructures, instead detecting capacitance changes through a planar electrode layout. This not only significantly reduces the difficulty and cost of the manufacturing process but also eliminates the performance drift risk caused by microstructure fatigue. Thus, it endows the robot with a six-degree-of-freedom tactile perception capability that is highly reliable, easily mass-producible, and capable of handling complex unstructured tasks such as precision assembly and flexible grasping.

[0041] See Figure 2 , Figure 2A schematic diagram of a detection layer according to an embodiment of this specification is shown. The detection layer includes a first detection electrode group, a second detection electrode group, and a third detection electrode group. The three detection electrode groups will now be described in detail.

[0042] The first detection electrode group includes a first detection electrode pair and a second detection electrode pair. The first detection electrode pair includes a first detection electrode and a second detection electrode that are centrally symmetrically distributed relative to the center point of the sensor, and whose symmetrical connection line is parallel to a first horizontal axis (X-axis) along a first horizontal direction. The second detection electrode pair includes a third detection electrode and a fourth detection electrode that are centrally symmetrically distributed relative to the center point of the sensor, and whose symmetrical connection line is parallel to a second horizontal axis (Y-axis) along a second horizontal direction.

[0043] The second detection electrode group includes a third detection electrode pair and a fourth detection electrode pair. The third detection electrode pair includes a fifth and a sixth detection electrode that are centrally symmetrically distributed relative to the center point of the sensor, and whose symmetrical line is parallel to the first horizontal axis. The fourth detection electrode pair includes a seventh and an eighth detection electrode that are centrally symmetrically distributed relative to the center point of the sensor, and whose symmetrical line is parallel to the second horizontal axis.

[0044] The horizontal distance from the third detection electrode pair to the second horizontal axis is greater than the horizontal distance from the first detection electrode pair to the second horizontal axis; the horizontal distance from the fourth detection electrode pair to the first horizontal axis is greater than the horizontal distance from the second detection electrode pair to the first horizontal axis.

[0045] The third detection electrode group includes a positive detection electrode pair and a negative detection electrode pair. The positive detection electrode pair includes a first positive detection electrode and a second positive detection electrode that are centrally symmetrically distributed relative to the center point of the sensor. The negative detection electrode pair includes a first negative detection electrode and a second negative detection electrode that are centrally symmetrically distributed relative to the center point of the sensor. The line connecting the centers of the first positive detection electrode and the second negative detection electrode is parallel to the second horizontal axis; the line connecting the centers of the first positive detection electrode and the first negative detection electrode is parallel to the first horizontal axis; and the line connecting the centers of the second positive detection electrode and the second negative detection electrode is parallel to the first horizontal axis.

[0046] In one optional embodiment of this specification, the capacitive tactile sensor further includes a first substrate and a second substrate, with a common layer disposed in the first substrate and a detection layer disposed in the second substrate.

[0047] It should be noted that the first substrate refers to the protective layer located on top of the sensor, which is usually made of flexible or semi-rigid insulating material. The first substrate can serve as a force-bearing contact surface, directly bearing externally applied contact (pressing, friction, etc.) and transmitting force to the common layer. At the same time, the first substrate can serve as a mounting carrier for the common layer, keeping the position of the common layer more stable relative to the second substrate.

[0048] The second substrate refers to the support plate located at the bottom of the sensor, and is usually made of rigid or semi-rigid insulating materials (such as printed circuit boards, ceramics, hard polymers, etc.). The second substrate is usually fixed to the robot end effector or mounting surface to keep the capacitive tactile sensor stable.

[0049] See Figure 3 , Figure 3 This specification illustrates a schematic diagram of a second capacitive tactile sensor according to an embodiment. The capacitive tactile sensor includes a first substrate, a common layer, a flexible dielectric layer, a detection layer, and a second substrate, which are sequentially disposed. The common layer is disposed on the first substrate, the detection layer is disposed on the second substrate, and the flexible dielectric layer is located between the first substrate and the second substrate.

[0050] When the first substrate is subjected to an external force, the common layer undergoes vertical compression or horizontal shear displacement relative to the stationary detection layer, resulting in a sensitive change in the capacitance value between the common layer and the detection layer, thus achieving efficient decoupling between vertical axial pressure and tangential force.

[0051] In one optional embodiment of this specification, the common layer includes a first common electrode and a second common electrode; The first common electrode and the first detection electrode group constitute the first detection unit, the first common electrode and the second detection electrode group constitute the second detection unit, and the second common electrode and the third detection electrode group constitute the third detection unit.

[0052] It should be noted that the first common electrode refers to the conductive portion located in the central region of the common layer, which has a continuous or segmented cross-shaped structure and serves as a common electrode for both the first and second detection units. Taking a cross-shaped electrode as an example, its cross shape is aligned with the mechanical neutral axis of the sensor's center point, ensuring that the electric field changes have clear symmetry under vertical compression and horizontal shearing, facilitating signal decoupling.

[0053] The second common electrode refers to the electrode used in conjunction with the third detection electrode group to form a third detection unit, which responds to torsional deformation with high sensitivity.

[0054] By applying the scheme of the embodiments in this specification, the first common electrode, the second common electrode, and the three sets of detection electrode groups in the detection layer are precisely paired to construct three functionally orthogonal and non-crosstalk detection units, realizing high-precision, low-coupling, and integrated mechanical information sensing with six degrees of freedom.

[0055] In one optional embodiment of this specification, the first detection electrode group includes a first detection electrode pair and a second detection electrode pair, and the second detection electrode group includes a third detection electrode pair and a fourth detection electrode pair. The projection of the first common electrode along the first horizontal direction covers the first detection electrode pair and the third detection electrode pair; the projection of the first common electrode along the second horizontal direction covers the second detection electrode pair and the fourth detection electrode pair; and the projection of the second common electrode covers the third detection electrode group.

[0056] It should be noted that the first horizontal direction refers to the first principal axis direction defined within the sensor contact surface (usually the XY plane), which typically corresponds to the X-axis.

[0057] The second horizontal direction refers to the second principal axis direction defined within the sensor contact surface, which usually corresponds to the Y-axis.

[0058] The scheme implemented in this specification utilizes a differentiated projection coverage strategy of the first common electrode in the first and second horizontal directions to map the mechanical deformation of the X and Y axes onto different combinations of detection electrode pairs (i.e., movement along the first horizontal direction mainly modulates the first and third detection electrode pairs, and movement along the second horizontal direction mainly modulates the second and fourth detection electrode pairs). Combined with the auxiliary excitation of the second common electrode, this not only naturally suppresses crosstalk between axes at the hardware level but also allows for the simultaneous and high-precision extraction of dual-axis tangential forces (first and second tangential forces), dual-axis torques (first and second torques around the horizontal axis), and vertical axial pressure through differential operations. This design significantly reduces the number of electrode traces and chip pin requirements, lowers system complexity, and simultaneously ensures high signal-to-noise ratio and linearity of signals in all dimensions under complex force scenarios (such as oblique pushing).

[0059] In one optional embodiment of this specification, the second common electrode includes a plurality of common electrode blocks; Multiple common electrode blocks are arranged circumferentially with the center point of the sensor as the pole, and the line connecting the pole and the center of the common electrode block is not parallel to the first horizontal axis and the second horizontal axis.

[0060] It should be noted that multiple common electrode blocks refer to independent conductive units that constitute the second common electrode. They are physically isolated but logically work together. Each common electrode block is responsible for sensing local capacitance changes within its coverage area.

[0061] Circumferential arrangement refers to multiple common electrode blocks distributed in a ring, radial, or polygonal pattern around the center point of the sensor. For example, multiple common electrode blocks can be located in the four corner areas of a common layer, distributed discretely at an angle. This angled arrangement allows for a greater relative area change or spacing change with the third detection electrode group below when the tactile sensor rotates, thereby improving the torque measurement sensitivity. Simultaneously, the second common electrode is physically separated from the first common electrode to avoid crosstalk of shear / pressure signals to the torque measurement channel.

[0062] The line connecting the sensor's center point to the center of any common electrode block is not parallel to the first and second horizontal axes. This means the angle between the line and the first horizontal axis (X-axis) and the second horizontal axis (Y-axis) is neither 0° nor 90° (typically designed as 45°, 30°, 60°, etc.). This arrangement avoids the common electrode block boundary coinciding with the main force axis, reducing measurement deviations caused by manufacturing errors or structural anisotropy. Furthermore, each common electrode block can simultaneously sense components in both the first and second horizontal directions, resulting in a smoother and more linear calculation of tangential force and torque.

[0063] The solution implemented in this specification, by dividing the second common electrode into multiple independent common electrode blocks arranged circumferentially at a specific angle, overcomes the limitations of traditional orthogonal electrode layouts in omnidirectional force sensing and high-order torque decoupling. By utilizing a geometric layout that is not parallel to the principal axis, each common electrode block can efficiently sense tangential components at any angle and torsional tendencies around the vertical axis. This not only significantly improves the detection sensitivity and linearity of tangential force and torque but also effectively suppresses axial crosstalk caused by structural anisotropy or alignment errors, achieving high-precision, low-delay synchronous measurement with six degrees of freedom.

[0064] In one optional embodiment of this specification, the plurality of common electrode blocks include a first common electrode block, a second common electrode block, a third common electrode block, and a fourth common electrode block; The first common electrode block, the second common electrode block, the third common electrode block, and the fourth common electrode block are symmetrically distributed along rays with polar angles of 45°, 135°, 225°, and 315°, respectively, with the center point of the sensor as the pole. The first common electrode block, the second common electrode block, the third common electrode block, and the fourth common electrode block are all equidistant from the pole.

[0065] It should be noted that the first, second, third, and fourth common electrode blocks refer to the four independent conductive blocks that constitute the second common electrode. They are usually identical in physical shape (e.g., sector, trapezoid, parallelogram, or rectangle), but strictly distinguishable in spatial location. Each common electrode block is responsible for collecting capacitance change information in its respective quadrant. The signal combination of the four blocks constitutes the complete two-dimensional plane and rotational dimension perception basis.

[0066] Applying the scheme of the embodiments in this specification, when the sensor is subjected to a force rotating around its center, the tangential displacement produced by the four common electrode blocks symmetrically distributed along rays with polar angles of 45°, 135°, 225°, and 315° is the largest, and the signal change is the most significant. The ray-symmetric distribution ensures that the sensor's mechanical properties are consistent in all directions (isotropic). Regardless of the direction of the force, the sensor's response curve is smooth and continuous, without the "angular effect" of being sensitive in one direction and sluggish in another. Furthermore, the equal radial distance from the poles ensures that the lever arm length provided by the four common electrode blocks is consistent when calculating the torque, preventing signals from being too strong or too weak in certain directions due to differences in distance from the center, ensuring gain consistency across the four channels, and reducing calibration difficulty.

[0067] See Figure 4 , Figure 4 This specification illustrates a schematic diagram of a common layer according to an embodiment of the present specification. The common layer includes a cross-shaped first common electrode and a second common electrode. The second common electrode includes a first common electrode block, a second common electrode block, a third common electrode block, and a fourth common electrode block. The first common electrode block, the second common electrode block, the third common electrode block, and the fourth common electrode block are symmetrically distributed along rays with polar angles of 45°, 135°, 225°, and 315°, respectively, with the sensor center point as the pole. The first common electrode block, the second common electrode block, the third common electrode block, and the fourth common electrode block are all equidistant from the pole.

[0068] See Figure 5 , Figure 5 This specification illustrates a schematic diagram of the positional relationship between a common layer and a detection layer according to an embodiment. After the capacitive tactile sensor is assembled, the two common electrodes in the common layer and the three sets of detection electrodes in the detection layer form 12 independent detectable capacitors. The three sets of detection electrodes include a first detection electrode and a second detection electrode, a third detection electrode and a fourth detection electrode, a fifth detection electrode and a sixth detection electrode, a seventh detection electrode and an eighth detection electrode, a first positive detection electrode and a second positive detection electrode, and a first negative detection electrode and a second negative detection electrode.

[0069] In one optional embodiment of this specification, the first detection electrode group includes a first detection electrode pair and a second detection electrode pair; The first detection electrodes are centrally symmetrically distributed relative to the center point of the sensor, and the line connecting the symmetrical electrodes is parallel to the first horizontal axis. The second detection electrodes are centrally symmetrically distributed relative to the center point of the sensor, and the line connecting the symmetrical electrodes is parallel to the second horizontal axis. The tangential force includes a first tangential force along a first horizontal direction and a second tangential force along a second horizontal direction; The first detection electrode pair and the common layer constitute a first detection unit for detecting the first tangential force; The second detection electrode pair and the common layer constitute a first detection unit for detecting the second tangential force.

[0070] It should be noted that the first detection electrode pair refers to a pair of electrodes located within the first detection electrode group, centrally symmetrically distributed relative to the center point of the sensor, and whose connecting line is parallel to the X-axis. Typically, this is represented by a rectangular or strip electrode on each side of the sensor's center point. The first detection electrode pair can detect horizontal thrust or frictional force along the X-axis. When the tactile sensor is subjected to a force to the right along the X-axis, the overlap area between the right electrode and the common layer increases (capacitance increases), while the overlap area on the left decreases (capacitance decreases). By calculating the difference between these two values, the magnitude and direction of the tangential force along the X-axis can be accurately determined.

[0071] The second detection electrode pair refers to another pair of electrodes located within the first detection electrode group, centrally symmetrically distributed relative to the center point of the sensor, with their connecting line parallel to the Y-axis. Typically, this is represented by a rectangular or strip electrode above and below the sensor's center point. The second detection electrode pair can detect horizontal thrust or frictional force along the Y-axis. When the tactile sensor is subjected to an upward force along the Y-axis, the overlap area between the upper electrode and the common layer increases (capacitance increases), while the lower electrode decreases (capacitance decreases). By calculating the difference, the magnitude and direction of the tangential force along the Y-axis can be accurately determined. Because the arrangement of the second detection electrode pair is perpendicular to the first detection electrode pair, the second detection electrode pair is insensitive to forces along the X-axis (or has minimal impact), thus ensuring that the measurement of horizontal thrust or frictional force along the Y-axis is not interfered with by horizontal thrust or frictional force along the X-axis.

[0072] The first tangential force refers to the frictional or shear force component acting on the sensor contact surface along the first horizontal direction (X-axis direction), used to reflect the sliding tendency or actual sliding state of the object relative to the sensor contact surface in the X-axis direction.

[0073] The second tangential force refers to the frictional or shear force component acting on the sensor contact surface along the second horizontal direction (Y-axis direction), used to reflect the sliding tendency or actual sliding state of the object relative to the sensor contact surface in the Y-axis direction. The first tangential force is independent of the first tangential force and is perpendicular (orthogonal) to the second tangential force.

[0074] In practical applications, when the first substrate is subjected to a first tangential force Fx along the X-axis, the common layer undergoes horizontal displacement relative to the X-axis detection layer. The area of ​​the first detection electrode pair facing the common layer changes by an equal magnitude but in opposite direction, while the area of ​​the other detection electrode pairs facing the common layer remains unchanged. At this time, the differential capacitance signal of the first detection electrode pair reflects the magnitude of the first tangential force Fx, calculated as Fx = capacitance of the first detection electrode - capacitance of the second detection electrode. Similarly, when the first substrate is subjected to a second tangential force Fy along the Y-axis, the common layer undergoes horizontal displacement relative to the Y-axis detection layer. The area of ​​the second detection electrode pair facing the common layer changes by an equal magnitude but in opposite direction, while the area of ​​the other detection electrode pairs facing the common layer remains unchanged. At this time, the differential capacitance signal of the second detection electrode pair reflects the magnitude of the second tangential force Fy, calculated as Fy = capacitance of the third detection electrode - capacitance of the fourth detection electrode.

[0075] By constructing an orthogonally symmetrical first detection electrode group and utilizing the strictly vertical distribution and central symmetry of the first and second detection electrode pairs in space, physical decoupling of the tangential force component is achieved. Combined with differential capacitance measurement technology, this not only significantly improves the sensitivity and linearity of tangential force detection but also effectively suppresses common-mode interference caused by vertical axial pressure and environmental noise. This allows the capacitive tactile sensor to accurately reproduce the two-dimensional friction vector (magnitude and direction) on the contact surface, providing reliable data for the robot to achieve precise anti-slip control and trajectory tracking.

[0076] In one optional embodiment of this specification, the second detection electrode group includes a third detection electrode pair and a fourth detection electrode pair; The third detection electrodes are centrally symmetrically distributed relative to the center point of the sensor, and the symmetrical line is parallel to the first horizontal axis. The fourth detection electrode pairs are centrally symmetrically distributed relative to the center point of the sensor, and the symmetrical line connecting them is parallel to the second horizontal axis; The torque about the horizontal axis includes a first torque about the horizontal axis about a first horizontal direction and a second torque about the horizontal axis about a second horizontal direction; The third detection electrode pair and the common layer constitute a second detection unit for detecting the first torque about the horizontal axis; The fourth detection electrode pair and the common layer constitute a second detection unit for detecting the second torque about the horizontal axis; The third detection electrode pair, the fourth detection electrode pair, and the common layer constitute a second detection unit for detecting vertical axial pressure.

[0077] It should be noted that the third detection electrode pair refers to a pair of electrodes located within the second detection electrode group, which are centrally symmetrically distributed relative to the center point of the sensor, and the line connecting them is parallel to the X-axis. Compared to the first detection electrode pair, the third detection electrode pair is typically located in the outer edge region of the detection layer.

[0078] The fourth detection electrode pair refers to another pair of electrodes located within the second detection electrode group, which are centrally symmetrically distributed relative to the center point of the sensor, and the line connecting them is parallel to the Y-axis. Compared to the second detection electrode pair, the fourth detection electrode pair is typically located in the outer edge region of the detection layer.

[0079] The first torque about the horizontal axis refers to the torque generated by the rotation of an object about the Y-axis. Physically, the first torque about the horizontal axis will cause the sensor to "tilt forward" or "tilt backward" (i.e., rotate about the Y-axis) along the X-axis.

[0080] The second torque about the horizontal axis refers to the torque generated by the rotation of an object about the X-axis. Physically, the second torque about the horizontal axis causes the sensor to "tilt forward" or "tilt backward" (i.e., rotate about the X-axis) along the Y-axis.

[0081] In practical applications, when the first substrate is subjected to a vertical axial pressure Fz, the spacing between the third and fourth detection electrode pairs and the common layer changes. At this time, the common-mode capacitance signal of the third and fourth detection electrode pairs can reflect the magnitude of the vertical axial pressure Fz, calculated as Fz = (capacitance of the fifth detection electrode + capacitance of the sixth detection electrode + capacitance of the seventh detection electrode + capacitance of the eighth detection electrode) / 4. When the first substrate is subjected to a second torque Mx about the horizontal axis, the spacing between the fourth detection electrode pairs and the common layer changes by an equal magnitude but opposite direction. At this time, the differential-mode capacitance signal of the fourth detection electrode pairs can reflect the magnitude of the second torque Mx about the horizontal axis, calculated as Mx = capacitance of the seventh detection electrode - capacitance of the eighth detection electrode. When the first substrate is subjected to a first torque My about the horizontal axis, the spacing between the third detection electrode pairs and the common layer changes by an equal magnitude but opposite direction. At this time, the differential-mode capacitance signal of the third detection electrode pairs can reflect the magnitude of the first torque My about the horizontal axis, calculated as My = capacitance of the fifth detection electrode - capacitance of the sixth detection electrode.

[0082] By applying the scheme of the embodiments in this specification, the first and second torques around the horizontal axis are independently extracted through a differential algorithm, achieving highly sensitive attitude perception. At the same time, the capacitance signals of the third and fourth detection electrode pairs are fused through a summation algorithm to accurately restore the vertical axial pressure. This design not only greatly simplifies the sensor structure (eliminating the need for additional pressure-specific electrodes), but also naturally utilizes the differential characteristics to eliminate the interference of torque on pressure measurement and the crosstalk of pressure on torque measurement, achieving high-precision synchronous detection of normal force and dual-axis torque in three dimensions with lower hardware cost.

[0083] In one optional embodiment of this specification, the first detection electrode group includes a first detection electrode pair and a second detection electrode pair, and the second detection electrode group includes a third detection electrode pair and a fourth detection electrode pair. The horizontal distance from the third detection electrode pair to the second horizontal axis is greater than the horizontal distance from the first detection electrode pair to the second horizontal axis; The horizontal distance from the fourth detection electrode pair to the first horizontal axis is greater than the horizontal distance from the second detection electrode pair to the first horizontal axis.

[0084] It should be noted that the horizontal distance refers to the vertical distance from the geometric center of the detection electrode pair to a specified horizontal axis (either the first or second horizontal axis). Mechanically, this is the length of the lever arm. The horizontal distance determines the sensitivity coefficient of the detection electrode pair to torque. A larger horizontal distance results in higher torque sensitivity; a smaller horizontal distance results in lower torque sensitivity.

[0085] By applying the scheme of the embodiments in this specification, the third and fourth detection electrode pairs are arranged at a position far from the central axis (long lever arm), which gives them extremely high sensitivity and signal amplification to small tilt angle changes; at the same time, the first and second detection electrode pairs are arranged relatively close to the axis (short lever arm), so that they mainly respond to tangential forces and are less affected by torque interference. This differentiated distance design allows the system to clearly separate the force component and torque component from the mixed signal through simple differential and weighted operations, effectively solving the problems of severe coupling of force and torque signals and difficulty in detecting small torques in traditional equidistant layouts, and significantly improving the resolution and dynamic range of the sensor in micro-operation feedback, posture recognition and multi-dimensional force and tactile perception.

[0086] In one optional embodiment of this specification, the third detection electrode group includes a positive detection electrode pair and a negative detection electrode pair; The positive detection electrodes are centrally symmetrically distributed relative to the center point of the sensor. The negative detection electrodes are centrally symmetrically distributed relative to the center point of the sensor.

[0087] It should be noted that the positive detection electrode pair refers to a pair of electrodes within the third detection electrode group that are centrally symmetrically distributed relative to the center point of the sensor. When the positive detection electrode pair is subjected to force, the overlap area between it and the common layer increases, resulting in a positive increase in capacitance.

[0088] The negative detection electrode pair refers to another pair of electrodes within the third detection electrode group that are centrally symmetrically distributed relative to the center point of the sensor. When the negative detection electrode pair is subjected to force, the overlap area between it and the common layer decreases, resulting in a negative decrease in capacitance.

[0089] In practical applications, when the first substrate is subjected to a torque Mz about the vertical axis, the first and second positive detection electrodes in the positive detection electrode pair change the same area opposite to the common layer, and the first and second negative detection electrodes in the negative detection electrode pair change the same area opposite to the common layer. The positive and negative detection electrode pairs change the same area opposite to the common layer, but in opposite directions. At this time, the differential capacitance signal of the positive and negative detection electrode pairs can reflect the magnitude of the torque Mz about the vertical axis. For example, the calculation formula Mz = [(capacitance of the first positive detection electrode + capacitance of the second positive detection electrode) / 2 - (capacitance of the first negative detection electrode + capacitance of the second negative detection electrode) / 2].

[0090] By applying the scheme of the embodiments in this specification, a third detection electrode group with a "positive and negative symmetrical differential" architecture is constructed. By utilizing the reverse response characteristics of the positive and negative detection electrode pairs when subjected to force, the effective signal amplitude is not only doubled (2ΔC), which significantly improves the signal-to-noise ratio and resolution of the capacitive tactile sensor, but also the symmetry of the positive and negative detection electrode pairs naturally cancels out common-mode noise such as vertical axial pressure, temperature drift, and electromagnetic interference. This enables the capacitive tactile sensor to achieve ultra-high precision, high linearity, and high stability independent detection of torque around the vertical axis in complex environments.

[0091] In one optional embodiment of this specification, the positive detection electrode pair includes a first positive detection electrode and a second positive detection electrode, and the negative detection electrode pair includes a first negative detection electrode and a second negative detection electrode. The line connecting the centers of the first positive detection electrode and the second negative detection electrode is parallel to the second horizontal axis; The line connecting the centers of the second positive detection electrode and the first negative detection electrode is parallel to the second horizontal axis; The line connecting the centers of the first positive detection electrode and the first negative detection electrode is parallel to the first horizontal axis; The line connecting the centers of the second positive detection electrode and the second negative detection electrode is parallel to the first horizontal axis.

[0092] By constructing a rectangular fully differential electrode array with "diagonal same sign and adjacent side opposite signs" using the scheme of the embodiments in this specification, decoupling detection of tangential force and torque and suppression of common-mode interference are achieved. Utilizing orthogonal parallel geometric constraints, displacement along the first horizontal axis primarily changes the capacitance difference between the first positive and first negative detection electrodes, and between the second positive and second negative detection electrodes. Similarly, displacement along the second horizontal axis primarily changes the capacitance difference between the first positive and second negative detection electrodes, and between the second positive and second negative detection electrodes, thus achieving natural isolation of the signal channels at the physical level. Simultaneously, due to the symmetrical spatial distribution of the positive and negative detection electrodes, non-specific environmental interferences (such as temperature drift and electromagnetic noise) act simultaneously on all detection electrodes and are canceled out in the differential operation, significantly improving the signal-to-noise ratio and linearity of multidimensional force measurement in complex dynamic environments.

[0093] See Figure 6 , Figure 6 This specification illustrates a schematic diagram of a third type of capacitive tactile sensor according to an embodiment. The capacitive tactile sensor includes a first substrate, a common layer, a flexible dielectric layer, a detection layer, and a second substrate arranged sequentially. The common layer is disposed on the first substrate, the detection layer is disposed on the second substrate, and the flexible dielectric layer is located between the first substrate and the second substrate. A contact area is provided above the first substrate.

[0094] In practical applications, when the contact area is simultaneously subjected to six degrees of freedom forces / torques, the common-mode signal of the second detection electrode group is only related to the vertical axial pressure Fz; the differential-mode signal of the third detection electrode group is only related to the torque Mz about the vertical axis; the capacitive differential-mode signal between the first detection electrode pair and the common layer is only affected by the first tangential force Fx and the first torque My about the horizontal axis; the capacitive differential-mode signal between the second detection electrode pair and the common layer is only affected by the second tangential force Fy and the second torque Mx about the horizontal axis. Since both the first tangential force Fx and the first torque My about the horizontal axis cause changes in the capacitive differential-mode signal between the first detection electrode pair and the common layer, signal aliasing occurs. Similarly, the second tangential force Fy and the second torque Mx about the horizontal axis also cause signal aliasing in the capacitive differential-mode signal between the second detection electrode pair and the common layer. To address this problem, in the embodiments of this specification, signal aliasing can be eliminated by either of the following two methods: First, the linear displacement Δd generated by the torque is proportional to the radius r from the center (Δd = r·θ). If the first and second detection electrode pairs are designed very close to the center point of the sensor (i.e., r≈0), when torsion (θ) occurs, because r is very small, the displacement of the first and second detection electrode pairs is negligible. Therefore, the capacitance change caused by the first and second horizontal axis torques My and Mx is extremely small. The first and second tangential forces Fx and Fy cause overall translation, which is independent of position, and the signal remains strong. Therefore, the interference of the first and second horizontal axis torques My and Mx can be ignored, achieving decoupling of the tangential force and the horizontal axis torque. Alternatively, the first and second horizontal axis torques My and Mx can be calculated using the differential mode signal of the second detection electrode group, and then the minor influence of the first and second horizontal axis torques My and Mx can be subtracted from the tangential force signal, thereby achieving high-precision decoupling of the tangential force and the horizontal axis torque. In summary, the capacitive tactile sensor proposed in this specification can achieve high-level decoupling of six degrees of freedom of force / torque.

[0095] It is worth noting that the specific structures mentioned in the embodiments of this specification (such as electrode shape, size, layout, and flexible dielectric layer construction) are merely exemplary embodiments intended to illustrate technical principles and are not the only limitations on the embodiments of this specification. In practical applications, various adjustments and designs can be made according to specific needs. For three different detection electrode groups, their geometric shape is not limited to rectangles or specific angles. For example, the four centrally symmetrically distributed second common electrodes can be rectangular or designed as parallelograms; their placement angle relative to the horizontal axis is not limited to 45 degrees and can be arbitrarily adjusted according to sensitivity requirements. For the flexible dielectric layer, its material composition and microstructure are highly customizable. In terms of materials, a single elastomer can be used, or it can be designed as a composite flexible material or a multilayer dielectric structure; in terms of micromorphology, it can be designed as a solid layer, or it can be constructed as a prism array, frustum array, or other microstructure forms to optimize mechanical response characteristics.

[0096] See Figure 7 , Figure 7 This specification shows a schematic diagram of a capacitive tactile sensing array according to one embodiment, which includes multiple capacitive tactile sensors.

[0097] It should be noted that for relevant information on capacitive tactile sensors, please refer to [link / reference needed]. Figure 1 The description of the capacitive tactile sensor shown in this specification will not be repeated here.

[0098] exist Figure 7 In the diagram, the four horizontal rows labeled "Transmitter" (Tx1, Tx2, Tx3, Tx4) and the four vertical columns labeled "Receiver" (Rx1 to Rx10, Rx11 to Rx20, Rx21 to Rx30, Rx31 to Rx40) represent... Figure 7 The capacitive tactile sensing array shown adopts a row and column scanning driving method, and reads signals through a large number of detection units. The overall structure is compact and regularly arranged, making it suitable for high-resolution tactile imaging and distributed force sensing systems.

[0099] A capacitive tactile sensor array refers to an array composed of multiple capacitive tactile sensors. In addition to multiple capacitive tactile sensors, a capacitive tactile sensor array can also include supporting scanning circuitry (row / column driving and reading) and signal processing units. This enables functions such as tactile imaging (generating a force distribution heatmap of the contact surface, visually displaying where the force is large and where it is small), multi-dimensional information calculation (calculating higher-order information such as the object's slip direction, friction coefficient distribution, and object hardness distribution), and dynamic trajectory tracking (continuously tracking the object's movement trajectory on the sensor contact surface to achieve anti-slip control and fine manipulation). The capacitance detection method of a capacitive tactile sensor array can adopt mutual capacitance or self-capacitance schemes.

[0100] By integrating multiple capacitive tactile sensors to construct a large-scale capacitive tactile sensing array, a leap from single-point mechanical measurement to high-resolution tactile imaging is achieved. Utilizing the spatial sampling capability of the capacitive tactile sensing array, a three-dimensional force distribution cloud map (including normal pressure and multi-dimensional tangential friction) on the contact surface can be reconstructed, thereby accurately identifying the geometry, surface texture, material hardness, and slippage trend of an object, thus endowing robots or intelligent devices with human-like fine manipulation and adaptive grasping capabilities.

[0101] In one optional embodiment of this specification, the common layer of the capacitive tactile sensor is connected to the transmitter, the detection layer is connected to the receiver, the transmitter is used to output an excitation signal, and the receiver is used to sense the capacitance change caused by touch. or, The common layer is grounded, and the detection layer is connected to the transmitter.

[0102] It should be noted that the transmitting end refers to the output port responsible for generating high-frequency AC excitation signals (such as sine waves, square waves, etc.). This signal is used to excite the capacitive electric field, causing charges to move between the electrodes, providing the alternating electric field energy required for the operation of the capacitive tactile sensor.

[0103] The receiving end refers to a highly sensitive input port responsible for detecting weak current or voltage changes. It is used to capture the small amount of charge transfer caused by capacitance changes, and together with the filtering circuit, it extracts the effective tactile signal from the background noise.

[0104] See Figure 8 , Figure 8This specification illustrates a schematic diagram of the connection relationship of a capacitive tactile sensor according to an embodiment. In this self-capacitive scheme, the common layer of the capacitive tactile sensor is grounded (Gnd), and the 12 detection electrodes in the detection layer are connected to the transmitter (Tx1 to Tx10). The capacitive tactile sensor array can scan and drive the 12 detection electrodes in the detection layer and detect the capacitance of each detection electrode relative to the common layer. In the capacitive tactile sensor array, the detection layer of each capacitive tactile sensor can be treated as a group, facilitating the wiring of the capacitive tactile sensor array and the data processing of the capacitive tactile sensor. Furthermore, each positive and negative detection electrode pair only requires one Tx terminal.

[0105] See Figure 9 , Figure 9 This specification illustrates another connection diagram for a capacitive tactile sensor according to an embodiment. In this mutual capacitance scheme, the common layer of the capacitive tactile sensor is connected to the transmitter (Tx), and the 12 detection electrodes in the detection layer are connected to the receiver (Rx1 to Rx10). The capacitive tactile sensor array can drive the common layer using time-division multiplexing (multiple Txes driven sequentially), code division, or frequency division (multiple Txes scan simultaneously but with different code values ​​or frequencies of driving signals). Furthermore, the positive detection electrode pair and the negative detection electrode pair each require only one Rx terminal.

[0106] Applying the solutions of the embodiments in this specification, in Figure 8 The illustrated solution utilizes the principle of self-capacity to significantly reduce circuit complexity and power consumption, making it suitable for cost-sensitive or low-interference consumer electronics and light-load scenarios; Figure 9 The illustrated solution, through the principle of mutual capacitance, greatly suppresses electromagnetic interference from the back side of the capacitive tactile sensor, ensuring signal purity. It is suitable for robot electronic skin installed in environments with strong interference, such as motors and metal frames. In summary, the solution proposed in the embodiments of this specification can maintain high sensitivity and high resolution while possessing strong environmental adaptability and anti-interference robustness, meeting diverse needs from precision industrial operations to daily human-machine interaction.

[0107] See Figure 10 , Figure 10 This specification illustrates a flowchart of a method for determining mechanical information according to an embodiment of the present invention. The method is applied to a capacitive tactile sensor and specifically includes the following steps: Step 1002: Acquire the first capacitance differential mode signal of the first detection unit in the capacitive tactile sensor, and determine the tangential force based on the first capacitance differential mode signal.

[0108] Step 1004: Collect the common-mode signal and differential-mode signal of the second detection unit in the capacitive tactile sensor, determine the vertical axial pressure based on the common-mode signal, and determine the torque around the horizontal axis based on the differential-mode signal.

[0109] Step 1006: Acquire the third capacitance differential mode signal of the third detection unit in the capacitive tactile sensor, and determine the torque about the vertical axis based on the third capacitance differential mode signal.

[0110] Wherein, the tangential force includes a first tangential force along the first horizontal direction and a second tangential force along the second horizontal direction, and the torque about the horizontal axis includes a first torque about the horizontal axis about the first horizontal direction and a second torque about the horizontal axis about the second horizontal direction; step 1002 may include steps 10022 to 10026.

[0111] Step 10022: Determine the initial first tangential force and the initial second tangential force based on the differential mode signal of the first capacitor.

[0112] Step 10024: Determine the first tangential force based on the initial first tangential force and the first moment about the horizontal axis.

[0113] Step 10026: Determine the second tangential force based on the initial second tangential force and the second torque about the horizontal axis.

[0114] It should be noted that the first capacitance differential mode signal refers to the capacitance differential mode signal of the first detection electrode pair and the capacitance differential mode signal of the second detection electrode pair. The capacitance common mode signal refers to the capacitance common mode signal of the third and fourth detection electrode pairs. The second capacitance differential mode signal refers to the capacitance differential mode signal of the third and fourth detection electrode pairs. The third capacitance differential mode signal refers to the capacitance differential mode signal of the positive and negative detection electrode pairs.

[0115] The methods for determining tangential force, vertical axial pressure, moment about the horizontal axis, and moment about the vertical axis can be found in [reference needed]. Figure 1 The relevant descriptions of the capacitive tactile sensor shown in this specification will not be repeated in the embodiments.

[0116] The initial first tangential force and the initial second tangential force refer to the uncompensated raw tangential force estimates calculated directly from the differential mode signal of the first capacitor. They contain the actual tangential force but also include coupling errors caused by the torque about the horizontal axis.

[0117] In practical applications, when determining the first tangential force based on the initial first tangential force and the first torque about the horizontal axis, the first tangential force Fx = initial first tangential force F'x - first torque about the horizontal axis My. When determining the second tangential force based on the initial second tangential force and the second torque about the horizontal axis, the second tangential force Fy = initial second tangential force F'y - second torque about the horizontal axis Mx.

[0118] By applying the scheme of the embodiments in this specification, the differential and common-mode characteristics of capacitive signals are utilized to achieve accurate and independent reconstruction of six-dimensional mechanical information (Fx, Fy, Fz, Mx, My, Mz). This architecture not only greatly reduces the coupling error between mechanical information of different dimensions and improves the linearity and signal-to-noise ratio of the measurement, but also simplifies the complexity of the back-end algorithm, enabling capacitive tactile sensors to simultaneously and sensitively perceive complex interactive actions such as pressing, rubbing, tilting, and twisting, just like human skin, providing a reliable six-dimensional force feedback basis for the precise operation of robots. Furthermore, in the process of determining the tangential force, the initial first tangential force and the initial second tangential force containing noise are first obtained. Then, the independently measured first and second moments about the horizontal axis are used as key correction parameters to accurately calculate the false tangential component caused by structural tilt and remove it from the initial first and second tangential forces, thereby outputting a high-fidelity true tangential force. This algorithm not only significantly reduces interdimensional crosstalk, enabling capacitive tactile sensors to accurately identify minute sliding operations even when subjected to huge vertical pressure or significant tilt, but also greatly improves the linearity and robustness of multidimensional force decoupling, allowing robots or interactive devices to distinguish between "forceful push" and "tilting pressure".

[0119] See Figure 11 , Figure 11 This specification shows a schematic diagram of a device with tactile sensing function according to an embodiment of the present specification. The device 1100 with tactile sensing function includes a capacitive tactile sensing array 1102.

[0120] It should be noted that devices with tactile sensing capabilities refer to intelligent devices that integrate capacitive tactile sensor arrays. They can not only perform mechanical actions or display information, but also actively sense the physical properties of external objects (such as pressure, texture roughness, sliding speed, and temperature). As a carrier and application terminal of tactile information, devices with tactile sensing capabilities are responsible for receiving raw data from the capacitive tactile sensors, converting it into understandable tactile images or feedback signals through algorithms, and adjusting their own behavior accordingly (such as the gripping force of a robot) or transmitting tactile sensations to the user (such as vibration feedback from a mobile phone). Devices with tactile sensing capabilities include, but are not limited to, robotic dexterous hands, intelligent prosthetics, and touchscreens with force feedback.

[0121] Tactile sensing refers to the ability of smart devices to collect and analyze multi-dimensional physical information such as vertical axis torque, tangential force, torque, vibration texture, slip trend, and temperature at the contact interface by integrating capacitive tactile sensor arrays to simulate the biological skin nervous system. This enables them not only to determine "whether there is contact" but also to accurately identify the shape, material, hardness, and dynamic interaction state of objects. This allows smart devices to perform compliant adaptive grasping, precise operation control, safe human-machine collaboration, and provide immersive force feedback in complex environments.

[0122] By integrating high-density capacitive tactile sensors into a capacitive tactile sensor array and embedding it into the device, the mechanical device is endowed with high-resolution multi-dimensional tactile perception capabilities similar to biological skin. This enables adaptive and compliant grasping of fragile items, precise identification of complex textures, and a deep understanding of human-computer interaction intentions, thereby improving the operational safety, operational accuracy, and naturalness of interaction of devices with tactile perception capabilities in unstructured environments.

[0123] The foregoing has described specific embodiments of this specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims may be performed in a different order than that shown in the embodiments and may still achieve the desired result. Furthermore, the processes depicted in the drawings do not necessarily require the specific or sequential order shown to achieve the desired result. In some embodiments, multitasking and parallel processing are possible or may be advantageous.

[0124] It should be noted that, for the sake of simplicity, the foregoing method embodiments are all described as a series of actions. However, those skilled in the art should understand that the embodiments in this specification are not limited to the described order of actions, because according to the embodiments in this specification, some steps can be performed in other orders or simultaneously. Furthermore, those skilled in the art should also understand that the embodiments described in this specification are all preferred embodiments, and the actions and modules involved are not necessarily essential to the embodiments in this specification.

[0125] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0126] The preferred embodiments disclosed above are merely illustrative of this specification. The optional embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the embodiments described herein. These embodiments are selected and specifically described in this specification to better explain the principles and practical applications of the embodiments, thereby enabling those skilled in the art to better understand and utilize this specification. This specification is limited only by the claims and their full scope and equivalents.

Claims

1. A capacitive tactile sensor, characterized in that, It includes a common layer and a detection layer with isolation settings, wherein the detection layer includes a first detection electrode group, a second detection electrode group and a third detection electrode group; The first detection electrode group and the common layer constitute a first detection unit for detecting tangential force; The second detection electrode group and the common layer constitute a second detection unit for detecting vertical axial pressure and torque about the horizontal axis; The third detection electrode group and the common layer constitute a third detection unit for detecting torque about the vertical axis.

2. The capacitive tactile sensor according to claim 1, characterized in that, The first detection electrode group includes a first detection electrode pair and a second detection electrode pair; The first detection electrodes are centrally symmetrically distributed relative to the center point of the sensor, and the symmetrical line is parallel to the first horizontal axis. The second detection electrode pair is centrally symmetrically distributed with respect to the center point of the sensor, and the line connecting the symmetries is parallel to the second horizontal axis; The tangential force includes a first tangential force along a first horizontal direction and a second tangential force along a second horizontal direction; The first detection electrode pair and the common layer constitute the first detection unit for detecting the first tangential force; The second detection electrode pair and the common layer constitute the first detection unit for detecting the second tangential force.

3. The capacitive tactile sensor according to claim 1, characterized in that, The second detection electrode group includes a third detection electrode pair and a fourth detection electrode pair; The third detection electrodes are centrally symmetrically distributed relative to the center point of the sensor, and the symmetrical line is parallel to the first horizontal axis. The fourth detection electrode pair is centrally symmetrically distributed relative to the center point of the sensor, and the symmetrical line is parallel to the second horizontal axis; The torque about the horizontal axis includes a first torque about the horizontal axis about a first horizontal direction and a second torque about the horizontal axis about a second horizontal direction; The third detection electrode pair and the common layer constitute the second detection unit for detecting the first torque about the horizontal axis; The fourth detection electrode pair and the common layer constitute the second detection unit for detecting the second torque about the horizontal axis; The third detection electrode pair, the fourth detection electrode pair, and the common layer constitute the second detection unit for detecting the vertical axial pressure.

4. The capacitive tactile sensor according to claim 1, characterized in that, The first detection electrode group includes a first detection electrode pair and a second detection electrode pair, and the second detection electrode group includes a third detection electrode pair and a fourth detection electrode pair; The horizontal distance from the third detection electrode pair to the second horizontal axis is greater than the horizontal distance from the first detection electrode pair to the second horizontal axis; The horizontal distance from the fourth detection electrode to the first horizontal axis is greater than the horizontal distance from the second detection electrode to the first horizontal axis.

5. The capacitive tactile sensor according to claim 1, characterized in that, The third detection electrode group includes a positive detection electrode pair and a negative detection electrode pair; The positive detection electrodes are centrally symmetrically distributed relative to the center point of the sensor. The negative detection electrodes are centrally symmetrically distributed relative to the center point of the sensor.

6. The capacitive tactile sensor according to claim 5, characterized in that, The positive detection electrode pair includes a first positive detection electrode and a second positive detection electrode, and the negative detection electrode pair includes a first negative detection electrode and a second negative detection electrode. The line connecting the centers of the first positive detection electrode and the second negative detection electrode is parallel to the second horizontal axis; The line connecting the centers of the second positive detection electrode and the first negative detection electrode is parallel to the second horizontal axis; The line connecting the centers of the first positive detection electrode and the first negative detection electrode is parallel to the first horizontal axis; The line connecting the centers of the second positive detection electrode and the second negative detection electrode is parallel to the first horizontal axis.

7. The capacitive tactile sensor according to any one of claims 1 to 6, characterized in that, The common layer includes a first common electrode and a second common electrode; The first common electrode and the first detection electrode group constitute the first detection unit, the first common electrode and the second detection electrode group constitute the second detection unit, and the second common electrode and the third detection electrode group constitute the third detection unit.

8. The capacitive tactile sensor according to claim 7, characterized in that, The first detection electrode group includes a first detection electrode pair and a second detection electrode pair, and the second detection electrode group includes a third detection electrode pair and a fourth detection electrode pair; The projection of the first common electrode along the first horizontal direction covers the first detection electrode pair and the third detection electrode pair; the projection of the first common electrode along the second horizontal direction covers the second detection electrode pair and the fourth detection electrode pair; and the projection of the second common electrode covers the third detection electrode group.

9. The capacitive tactile sensor according to claim 7, characterized in that, The second common electrode includes multiple common electrode blocks; The plurality of common electrode blocks are arranged circumferentially with the center point of the sensor as the pole, and the line connecting the pole and the center of the common electrode block is not parallel to the first horizontal axis and the second horizontal axis.

10. The capacitive tactile sensor according to claim 9, characterized in that, The plurality of common electrode blocks include a first common electrode block, a second common electrode block, a third common electrode block, and a fourth common electrode block; The first common electrode block, the second common electrode block, the third common electrode block, and the fourth common electrode block are symmetrically distributed along rays with polar angles of 45°, 135°, 225°, and 315°, respectively, with the center point of the sensor as the pole. The first common electrode block, the second common electrode block, the third common electrode block, and the fourth common electrode block are all equidistant from the pole.

11. A capacitive tactile sensing array, characterized in that, It includes a plurality of capacitive tactile sensors as described in any one of claims 1 to 10.

12. The capacitive tactile sensing array according to claim 11, characterized in that, The common layer of the capacitive tactile sensor is connected to the transmitter, and the detection layer is connected to the receiver. The transmitter is used to output an excitation signal, and the receiver is used to sense the capacitance change caused by touch. or, The common layer is grounded, and the detection layer is connected to the transmitter.

13. A method for determining mechanical information, characterized in that, Applied to a capacitive tactile sensor as described in any one of claims 1 to 10; the method includes: The first capacitance differential mode signal of the first detection unit in the capacitive tactile sensor is acquired, and the tangential force is determined based on the first capacitance differential mode signal. The common-mode signal and differential-mode signal of the second detection unit in the capacitive tactile sensor are collected. The vertical axial pressure is determined based on the common-mode signal, and the torque about the horizontal axis is determined based on the differential-mode signal. The third capacitance differential mode signal of the third detection unit in the capacitive tactile sensor is acquired, and the torque about the vertical axis is determined based on the third capacitance differential mode signal. The tangential force includes a first tangential force along a first horizontal direction and a second tangential force along a second horizontal direction, and the torque about the horizontal axis includes a first torque about the horizontal axis about the first horizontal direction and a second torque about the horizontal axis about the second horizontal direction; The step of determining the tangential force based on the first capacitance differential mode signal includes: The initial first tangential force and the initial second tangential force are determined based on the first capacitor differential mode signal; The first tangential force is determined based on the initial first tangential force and the first torque about the horizontal axis; The second tangential force is determined based on the initial second tangential force and the second torque about the horizontal axis.

14. A device with tactile sensing function, characterized in that, Including the capacitive tactile sensing array as described in claim 11.

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