Flexible touch sensing chip for body intelligence and electronic skin module thereof

Abstract

The invention discloses a flexible touch sensing chip for body intelligence and an electronic skin module thereof. The flexible touch sensing chip at least comprises a control processor, a multiplexer, an analog-to-digital converter and a digital interface. Each row gating channel and each column gating channel of the multiplexer are realized by a three-state group, the three-state group comprises a high-resistance state, a middle-resistance state and a low-resistance state, the high-resistance state is used for cutting off signal paths among the channels, and the middle-resistance state and the low-resistance state are both used for realizing gating of signals among the channels. The multiplexer is stable in on-resistance, is slightly influenced by temperature and voltage fluctuation, and is easy to expand. The flexible tactile sensing chip is highly integrated, does not need discrete components to build a rigid circuit, can be seamlessly attached to the flexible tactile sensor, and is suitable for complex dynamic curved surfaces such as robot fingers and joints.

Description

Technical Field

[0001] This invention relates to the field of embodied intelligence technology, and more specifically to a flexible tactile sensing chip for embodied intelligence and its electronic skin module. Background Technology

[0002] In the field of embodied intelligence, flexible tactile sensing, as a core technology that endows intelligent agents with near-biological skin interaction capabilities, has become a key focus of industry research and development. Currently, mainstream flexible tactile sensing solutions are based on traditional CMOS multiplexers and operational amplifiers to construct flexible piezoresistive array sensing systems. These systems use an M-row × N-column passive matrix piezoresistive sensing array to form the tactile sensing interface. Two independent external multiplexers are used to achieve row or column time-division scanning selection. A voltage divider circuit and operational amplifier are used to amplify the signal. Virtual shorting technology is used to suppress crosstalk. The flexible sensor array, microcontroller, discrete chips, and peripheral components are integrated at the board level through a rigid printed circuit board.

[0003] However, existing technical solutions have the following drawbacks in practical applications: they are built using discrete components, resulting in low integration and rigid form, making it impossible to seamlessly integrate with flexible sensors onto complex dynamic curved surfaces such as robot fingers and joints, thus compromising the biomimetic design and motion performance of the embodied intelligent agent; the expansion of traditional CMOS multiplexers leads to a significant increase in control pin and wiring complexity and power consumption when building large-scale arrays; the non-ideal on-resistance of CMOS switches is easily affected by temperature and voltage, and the superimposed parasitic capacitance and turn-off leakage of the switches cause measurement errors, long-term drift, and residual crosstalk, making it difficult to meet the requirements of high-precision sensing; the system only outputs raw data, lacking hardware-level preprocessing optimization, and a large number of data processing tasks rely on the host computer, resulting in increased communication latency and failing to meet real-time control requirements.

[0004] Therefore, how to effectively address the deficiencies and shortcomings of existing technologies has become an important issue that researchers in this field urgently need to solve. Summary of the Invention

[0005] The purpose of this invention is to address the above-mentioned problems by providing a flexible tactile sensing chip for embodied intelligence and its electronic skin module.

[0006] The technical solution of this invention is: a flexible tactile sensing chip for embodied intelligence, comprising at least: The control processor is used to generate the scanning control timing, process the digital signal output by the analog-to-digital converter to obtain tactile data, and output it to the digital interface. A multiplexer is used to enable signal selection between the tactile sensor and the internal signal bus of the chip, and output analog signals to the analog-to-digital converter. The multiplexer includes row selection channels and column selection channels. Each row selection channel and column selection channel is implemented by a tri-state group, which includes three states: high impedance, medium impedance, and low impedance. The high impedance state is used to cut off the signal path between channels, and the medium impedance and low impedance states are used to enable signal selection between channels. An analog-to-digital converter is used to convert analog signals output from a multiplexer into digital signals and output them to a control processor. A digital interface is used to receive tactile data from the control processor and output it to the embodied intelligent agent; The control processor applies three discrete voltages to the three-state group according to the scan control timing to achieve switching between high-resistance, medium-resistance and low-resistance states.

[0007] As an improvement of this embodiment of the invention, when the voltage applied by the control processor to the three-state group is equal to the first voltage, the state of the three-state group is high resistance, and the resistance of the three-state group is greater than or equal to the first resistance; when the voltage applied by the control processor to the three-state group is equal to the second voltage, the state of the three-state group is medium resistance, and the first resistance is greater than or equal to the resistance of the three-state group and the second resistance; when the voltage applied by the control processor to the three-state device is equal to the third voltage, the state of the three-state group is low resistance, and the resistance of the three-state device is less than or equal to the third resistance; wherein, the first resistance > the second resistance > the third resistance.

[0008] As an improvement to an embodiment of the present invention, the tri-state group includes at least a tri-state device and a switching transistor connected to the tri-state device.

[0009] As an improvement to an embodiment of the present invention, the tri-state group further includes a transimpedance amplifier connected between the tri-state device and the switching transistor.

[0010] As an improvement of this embodiment of the invention, the flexible tactile sensing chip further includes a signal conditioning circuit, which integrates an amplifier and a virtual ground generation circuit. The amplifier is used to receive and amplify the analog signal output by the multiplexer, and output the amplified analog signal to the analog-to-digital converter. The virtual ground generation circuit is used to provide a reference potential for the unselected row or column gating channels.

[0011] To achieve one of the above-mentioned objectives, one embodiment of the present invention provides an electronic skin module for embodied intelligence. The electronic skin module includes a flexible sensing layer and a flexible tactile sensing chip as described in any of the above claims. The flexible sensing layer is used to collect tactile signals of the embodied intelligent entity and output them to the flexible tactile sensing chip. The flexible tactile sensing chip is connected to the main controller of the embodied intelligent entity to form an interaction link.

[0012] As an improvement of this invention, multiple electronic skin modules are cascaded and expanded through the digital interface of the flexible tactile sensing chip to form a large-area tactile sensing network.

[0013] As an improvement of this embodiment of the invention, when multiple electronic skin modules are cascaded, master and slave nodes are divided by address configuration, and the master node reads data from the slave node by polling.

[0014] As an improvement to an embodiment of the present invention, the flexible sensing layer is a flexible thin-film piezoresistive array sensor with M rows × N columns, where M and N are both positive integers.

[0015] As an improvement of this embodiment of the invention, the substrate of the flexible sensing layer is a polyimide film.

[0016] The flexible tactile sensing chip and its electronic skin module for embodied intelligence provided in this invention have the following advantages: 1. This invention uses a multiplexer composed of three-state groups. Each channel is independent and has extremely high isolation when turned off. When expanding the array size, only control address lines need to be added, without the need for complex decoding circuits. This effectively breaks through the scalability bottleneck of traditional solutions and enables large-scale, high-density tactile array deployment.

[0017] 2. The three-state group has stable on-resistance and is less affected by temperature and voltage fluctuations, reducing measurement errors and long-term drift, and can capture subtle pressure changes and tactile information.

[0018] 3. The control processor integrates data preprocessing functions, reducing the main control burden and communication latency of the embodied intelligent agent, and improving the safety and intelligence of human-computer interaction.

[0019] 4. The flexible tactile sensing chip described in this invention is highly integrated, eliminating the need for discrete components to build rigid circuits. It can be seamlessly integrated with flexible tactile sensors and is suitable for complex dynamic curved surfaces such as robot fingers and joints. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structural connection of the flexible tactile sensing chip for embodied intelligence described in this invention; Figure 2 This is a schematic diagram of the three-state group described in this invention; Figure 3 This is a schematic diagram of the three-state group structure described in this invention. Figure 1 ; Figure 4 This is a schematic diagram of the three-state group structure described in this invention. Figure 2 ; Figure 5 This is a schematic diagram of the three-state group structure described in this invention. Figure 3 ; Figure 6 This is a schematic diagram of the three-state group structure described in this invention. Figure 4 ; Figure 7 This is a schematic diagram of the structural connection of the electronic skin module for embodied intelligence as described in this invention. Detailed Implementation

[0021] The present invention will now be described in detail with reference to the specific embodiments shown in the accompanying drawings. However, these embodiments do not limit the present invention, and any structural, methodological, or functional modifications made by those skilled in the art based on these embodiments are included within the scope of protection of the present invention.

[0022] If the present invention involves orientation (e.g., up, down, left, right, front, back, outside, inside, etc.) when described, then the orientations involved need to be defined.

[0023] The scope of the embodiments described herein includes the entire scope of the claims and all available equivalents thereof. Throughout this document, the terms “first,” “second,” etc., are used only to distinguish one element from another without requiring or implying any actual relationship or order between the elements. Indeed, a first element can also be referred to as a second element, and vice versa. Furthermore, the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a structure, apparatus, or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a structure, apparatus, or device. Without further limitations, an element defined by the phrase “comprising one…” does not exclude the presence of other identical elements in the structure, apparatus, or device that includes said element. The various embodiments described herein are presented in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably.

[0024] The terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer" used in this document to indicate orientation or positional relationships are based on the orientation or positional relationships shown in the accompanying drawings and are used only for the convenience of describing this document and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the invention. In the description herein, unless otherwise specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to mechanical or electrical connections, or internal connections between two elements, or direct connections or indirect connections through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0025] This invention provides a flexible tactile sensing chip for embodied intelligence, such as... Figure 1 As shown, it includes: The control processor 201 is used to generate scanning control timing, process the digital signal output by the analog-to-digital converter 203 to obtain tactile data and output it to the digital interface 204; In practice, the control processor 201 can be a processor core or a hard-connected state machine. The processor core is a hardware unit with general computing capabilities, executing pre-stored instruction sequences to perform data processing and timing control functions. The processor core pre-stores a scan control timing generation program and a digital signal processing algorithm. The digital signal output from the analog-to-digital converter 203 is transmitted to the processor core's storage unit via a data bus. The processor core calls the preset digital signal processing algorithm to filter and reduce noise in the digital signal, eliminating interference components and extracting effective feature parameters reflecting tactile perception to form standardized tactile data. The processor core transmits the tactile data to the digital interface 204 through an internal interface circuit. The digital interface 204 completes data format conversion and transmission control according to a preset communication protocol, achieving stable output of tactile data to external devices.

[0026] A hard-connected state machine is a dedicated module that directly implements fixed logic functions through hardware circuitry. It consists of combinational logic circuits and a storage unit, responding to input signals according to preset state transition rules without requiring instruction execution. The hard-connected state machine uses hardware circuitry to solidify the scan control timing logic. The internal storage unit is pre-configured with timing parameters, including sampling intervals and signal output timing. Driven by a clock signal, it sequentially outputs scan control signals according to fixed logic. The digital signal output from the analog-to-digital converter 203 is input to the hard-connected state machine. The hard-connected state machine uses hardware logic circuitry to filter and reduce noise in the digital signal to obtain the required tactile data. The hard-connected state machine connects to the digital interface 204 via a dedicated interface circuit, transmitting the processed tactile data to the digital interface 204.

[0027] Multiplexer 202 is used to enable signal selection between the tactile sensor and the internal signal bus of the chip, and outputs analog signals to analog-to-digital converter 203; the multiplexer 202 includes row selection channels and column selection channels, each of which is implemented by a tri-state group. Figure 2 As shown, the three-state group includes three states: high-resistance Stage 3, medium-resistance Stage 2, and low-resistance Stage 1. High-resistance Stage 3 is used to cut off the signal path between channels, while medium-resistance Stage 2 and low-resistance Stage 1 are used to select signals between channels. The control processor 201 applies three discrete voltages to the three-state group according to the scan control timing to switch between high-resistance Stage 3, medium-resistance Stage 2, and low-resistance Stage 1. Specifically, during the scan cycle, high-resistance Stage 3 cuts off currently unselected channels to avoid crosstalk between signals from different tactile sensors; medium-resistance Stage 2 and low-resistance Stage 1 respectively select tactile sensor channels with different priorities or signal strengths, allowing the analog signals of the corresponding sensors to be transmitted orderly to the internal signal bus of the chip.

[0028] In this embodiment, when the gate voltage of the tri-state device equals the first voltage, it is in a high-resistance state (Stage 3), and the resistance of the tri-state device is greater than or equal to the first resistance. When the gate voltage of the tri-state device equals the second voltage, it is in a medium-resistance state (Stage 2), and the first resistance is greater than or equal to the resistance of the tri-state device, which in turn is greater than or equal to the second resistance. When the gate voltage of the tri-state device equals the third voltage, it is in a low-resistance state (Stage 1), and the resistance of the tri-state device is less than or equal to the third resistance. Wherein, the first resistance > the second resistance > the third resistance. Here, in some specific embodiments, such as... Figure 2 As shown, the first voltage can be -4V to 0V, the second voltage can be -8V to -4V, and the third voltage can be -10V to -8V.

[0029] In some specific embodiments, the tri-state group includes at least a tri-state device A and a switching transistor connected to the tri-state device A. The tri-state device A is a state control element, which operates by receiving discrete voltage signals from the control processor 201 and changing its own resistance value to switch between high-resistance, medium-resistance, and low-resistance states, thereby controlling the on / off state of the signal path. The switching transistor is a path control actuator, which controls the conduction and cutoff between the drain and source through the voltage signal received at its gate, and is used to amplify the state control signal of the tri-state device A.

[0030] In practice, the switching transistor can be a PMOS or an NMOS, such as... Figure 3 and Figure 4 As shown, the third pin of the tri-state device A is connected to the power supply VDD via resistor R1 and is connected to the gate of the switching transistor. The first pin is grounded, and the second pin receives the voltage signal applied by the control processor 201. Resistor R1 is used to limit the gate current, protect the gate of the switching transistor from overcurrent damage, and stabilize the gate voltage to avoid false triggering of the switching transistor due to voltage fluctuations.

[0031] In some specific embodiments, the tri-state group further includes a transimpedance amplifier connected between the tri-state device A and the switching transistor. The transimpedance amplifier can convert the current signal output by the tri-state device A into a voltage signal and linearly amplify it to solve the problems of weak output signal and poor load-carrying capacity of the tri-state device A, while suppressing noise interference in signal transmission.

[0032] In practice, such as Figure 5 and Figure 6 As shown, the transimpedance amplifier includes amplifier U1 and capacitor C1 and resistor R3 connected in parallel with amplifier U1. Amplifier U1 receives the current signal from the tri-state device A through its inverting input, converts it into a voltage signal through internal circuitry, and outputs it from the output terminal, thus realizing current-to-voltage conversion and signal amplification. Capacitor C1 is used to stabilize the amplified voltage signal and prevent high-frequency oscillations from affecting the control accuracy of the switching transistor. Resistor R3 is a feedback resistor; by setting the feedback resistance value, the amplification factor and bandwidth of the amplifier are adjusted to match the output characteristics of the tri-state device A and the input requirements of the switching transistor. The inverting input terminal of amplifier U1 is connected to the third pin of the tri-state device A, the non-inverting input terminal is grounded, and the output terminal is connected to the gate of the switching transistor.

[0033] The analog-to-digital converter 203 is used to convert the analog signal output by the multiplexer 202 into a digital signal and output it to the control processor 201. Preferably, the analog-to-digital converter 203 is a high-precision analog-to-digital converter, specifically a high-speed, high-resolution SAR-ADC (Successive Approximation Register-Analog to Digital Converter) or Sigma-Delta ADC.

[0034] When a SAR-ADC is selected as the analog-to-digital converter 203, the reference voltage of the SAR-ADC is provided by a stable reference voltage source with an accuracy of not less than 0.1%. The analog signal input terminal of the SAR-ADC is connected to the output terminal of the multiplexer 202 through a low-noise buffer. The buffer is used to isolate the multiplexer 202 from the SAR-ADC, reduce interference and attenuation during signal transmission, and provide sufficient drive capability to ensure that the SAR-ADC can accurately acquire analog signals. The digital signal output terminal of the SAR-ADC is connected to the control processor 201 through a synchronous serial interface or a parallel interface. The interface communication rate is matched with the conversion rate of the SAR-ADC, so that the digital signal can be transmitted to the control processor 201 in a timely and lossless manner.

[0035] When a Sigma-Delta ADC is selected as the analog-to-digital converter 203, the integrator of the Sigma-Delta ADC can be constructed using a low-drift operational amplifier. The input bias current of the operational amplifier should not exceed 1 nanoamp, and the input offset voltage should not exceed 10 microvolts, reducing drift and errors during integration. The digital filter of the Sigma-Delta ADC can be a finite impulse response filter. The cutoff frequency of the filter is set according to the bandwidth of the input analog signal, allowing the effective signal to pass completely while filtering out high-frequency noise. The digital signal output of the Sigma-Delta ADC is connected to the control processor 201 through a serial peripheral interface. The interface uses synchronous communication to ensure the synchronization and accuracy of data transmission.

[0036] Digital interface 204 is used to receive tactile data from control processor 201 and output it to the embodied intelligent agent; Here, the digital interface 204 can be I2C, SPI, or a custom high-speed serial interface. The I2C interface is an internal integrated circuit interface, a two-wire synchronous serial communication interface consisting of a data line and a clock line. The I2C working principle is based on a master-slave communication architecture, with the control processor 201 acting as the master device and the digital interface 204 as the slave device. The master device outputs a synchronous clock signal through the clock line and achieves bidirectional data transmission through the data line. The I2C interface can support multiple master and slave devices, achieving data addressing through the slave device address. Communication speeds are divided into standard mode, normal mode, and high-speed mode, meeting the stable transmission requirements of medium-speed data such as tactile data. The SPI interface is a serial peripheral interface, a four-wire synchronous serial communication interface, including master output / slave input lines, master input / slave output lines, a clock line, and a chip select line. The SPI interface operates on a full-duplex synchronous communication principle. The control processor 201 acts as the master device, providing a synchronous clock signal through the clock line. The chip select line is used to select the target slave device. The master and slave devices simultaneously send and receive data through two dedicated data lines, without an address addressing process.

[0037] When the I2C interface is selected as the digital interface 204, the communication rate of the I2C interface can be set to standard mode or normal mode, which can be flexibly selected according to the amount of tactile data transmitted and the real-time requirements. The standard mode is suitable for scenarios with small data volume and general real-time requirements, while the normal mode is suitable for scenarios with medium data volume and high real-time requirements.

[0038] When the SPI interface is selected as the digital interface 204, all four signal lines of the SPI interface adopt differential transmission. Differential signal lines reduce common-mode interference and improve the anti-interference capability of signal transmission. The clock polarity and clock phase of the SPI interface are set according to the SPI master interface configuration of the control processor 201 to synchronize the clocks of the master and slave devices and avoid data sampling errors. The communication rate of the SPI interface is set according to the tactile data transmission rate requirements. The minimum communication rate is not less than 1 megabit per second, and the maximum communication rate does not exceed the maximum supported rate of the embodied intelligent agent's SPI interface, ensuring fast and stable data transmission. The chip select line of the SPI interface is controlled by hardware logic. When the control processor 201 transmits tactile data to the embodied intelligent agent, the chip select line is pulled low to select the target embodied intelligent agent; after the data transmission is completed, the chip select line is pulled high to release it. While transmitting tactile data, the SPI interface can receive status data feedback from the embodied intelligent agent, realizing bidirectional data interaction.

[0039] The signal conditioning circuit 205 integrates an amplifier and a virtual ground generation circuit. The amplifier is used to receive and amplify the analog signal output by the multiplexer 202, and output the amplified analog signal to the analog-to-digital converter 203. The virtual ground generation circuit is used to provide a reference potential for the unselected row or column gating channels.

[0040] In practice, the amplifier can adopt an instrumentation amplifier architecture with an input impedance of not less than 100 megohms, an input offset voltage of not more than 20 microvolts, an equivalent input noise voltage of not more than 10 nanovolts per square Hz, and a common-mode rejection ratio of not less than 80 dB. This architecture can effectively amplify weak analog signals and suppress common-mode interference. The amplifier's gain is adjusted via an external resistor network composed of high-precision metal film resistors. The gain adjustment range is from 1 to 100 times, and can be set according to the amplitude of the analog signal output by the multiplexer 202, ensuring that the amplified signal amplitude is within the input range of the analog-to-digital converter 203 and does not exceed the maximum input voltage of the analog-to-digital converter 203.

[0041] The non-inverting input of the amplifier is connected to the signal output of the multiplexer 202, and the inverting input of the amplifier is connected to the output through a feedback resistor to form a negative feedback loop, ensuring the linearity of the amplification process. A current-limiting resistor can be connected in series at the output of the amplifier. The resistance value of the current-limiting resistor is in the range of 100 ohms to 1 kiloohms, which is used to limit the output current and prevent the amplifier from being damaged due to a short circuit at the input of the analog-to-digital converter 203.

[0042] The virtual ground generation circuit can be configured as a voltage follower using an operational amplifier. The output of the virtual ground generation circuit is connected to all row and column selection channels of the multiplexer 202 through multiple branch lines. When the multiplexer 202 selects a row and a column selection channel for signal transmission, the virtual ground generation circuit continuously provides a stable reference potential for the remaining unselected row and column selection channels, so that the potential of the unselected channels is stable and no parasitic voltage or interference signal is generated, thereby avoiding crosstalk between channels.

[0043] This invention also provides an electronic skin module for embodied intelligence, such as... Figure 7 As shown, the electronic skin module includes a flexible sensing layer 1 and a flexible tactile sensing chip 2 as described above. The flexible sensing layer 1 is used to collect tactile signals of the embodied intelligent agent and output them to the flexible tactile sensing chip 2. The flexible tactile sensing chip 2 is connected to the main controller of the embodied intelligent agent to form an interaction link.

[0044] In some specific embodiments, the flexible sensing layer 1 is a structure integrating a flexible polymer substrate with a sensing unit array. The flexible polymer substrate can be polyimide or silicone rubber. Preferably, the present invention uses a polyimide film as the flexible polymer substrate. The polyimide film has good flexibility and tensile properties, can conform to the curved surface of the embodied intelligent body, and can maintain stable performance after repeated bending and stretching. The substrate thickness ranges from 50 micrometers to 200 micrometers, providing sufficient structural support while maintaining the thinness of the sensing layer, thus preventing damage to the sensing units under pressure.

[0045] The sensing unit array can specifically be an M-row × N-column flexible thin-film piezoresistive array sensor, where M and N are both positive integers. The flexible thin-film piezoresistive array sensor is matrix-distributed on the surface of a flexible polymer substrate. The array size is set according to the tactile perception requirements of the embodied intelligent agent, with a center-to-center spacing of 1 mm to 5 mm between adjacent sensing units, achieving high-resolution acquisition of tactile signals. Here, the piezoresistive sensor is a flexible conductive composite material, whose resistance changes linearly with pressure, and its sensitivity is not less than 0.5 kΩ per Newton, used for effective response to weak tactile signals.

[0046] The signal output terminal of the flexible sensing layer 1 is provided with a flexible printed circuit interface. The number of interface pins matches the number of row selection channels and column selection channels of the sensing unit array. Each pin is connected to the corresponding sensing unit electrode through conductive silver paste.

[0047] In some specific embodiments, the flexible tactile sensing chip 2 is packaged on a flexible substrate. The substrate material is the same as the base material of the flexible sensing layer 1, and the thickness of the packaged chip does not exceed 300 micrometers, allowing it to be bonded and integrated with the flexible sensing layer 1. The input interface of the flexible tactile sensing chip 2 and the flexible printed circuit interface of the flexible sensing layer 1 can be connected by bonding with anisotropic conductive adhesive. The internal circuitry of the flexible tactile sensing chip 2 is consistent with any embodiment of the flexible tactile sensing chip 2. The row selection channel and column selection channel of its multiplexer are respectively connected to the row selection channel and column selection channel of the flexible sensing layer 1, enabling point-by-point scanning acquisition of the sensing unit array.

[0048] The flexible tactile sensing chip 2 establishes a wired connection with the main controller of the embodied intelligent agent via a digital interface. The transmission cable is a flexible shielded cable with an outer diameter not exceeding 1 mm. Internally, it includes power signal lines, data signal lines, and a ground wire. The grounding resistance of the shielding layer is no greater than 1 ohm to reduce the impact of external electromagnetic interference on data transmission. The interactive link allows for bidirectional data transmission. Configuration commands transmitted from the main controller to the flexible tactile sensing chip 2 include parameters such as the sensing unit scanning frequency, signal amplification factor, and analog-to-digital conversion rate. These commands are transmitted through control frames via the digital interface. The control frame contains an address field, a command field, and a check field. The address field uniquely identifies the flexible tactile sensing chip 2 to avoid conflicts with other peripherals. The tactile data frames transmitted from the flexible tactile sensing chip 2 to the main controller include a frame header data field and a check field. The frame header is used by the main controller to identify the start of the data. The data field contains the tactile digitization data of each sensing unit. The check field uses a CRC check algorithm to ensure the accuracy of data transmission.

[0049] In some specific embodiments, the outer surface of the flexible sensing layer 1 is covered with a transparent flexible protective film. The protective film material can be polyethylene terephthalate or polytetrafluoroethylene, with a thickness of 20 micrometers to 50 micrometers. It has scratch-resistant, wear-resistant, and waterproof properties, and a surface hardness of not less than 4H, effectively protecting the sensing unit from damage by the external environment without affecting the sensitivity of tactile signal acquisition. The protective film is fixed to the flexible sensing layer 1 by electrostatic adsorption or weak adhesive bonding, facilitating cleaning and replacement. The electronic skin module is attached to the surface of the embodied intelligent body using a flexible adhesive.

[0050] To achieve large-area, high-coverage tactile perception on the body surface of the embodied intelligent agent, in this embodiment, multiple electronic skin modules are cascaded and expanded through the digital interface of the flexible tactile sensing chip 2 to form a large-area tactile sensing network. Specifically, multiple electronic skin modules can be cascaded using a daisy-chain topology or a star topology, selected according to the body surface shape and sensing coverage requirements of the embodied intelligent agent. In a daisy-chain topology, the output terminal of the flexible tactile sensing chip 2 of the first electronic skin module is directly connected to the input terminal of the digital interface of the second electronic skin module. Then, each electronic skin module is connected sequentially end-to-end, forming a serial cascaded link. Finally, the output terminal of the last electronic skin module is connected to the main controller of the embodied intelligent agent, suitable for long, narrow, or curved body surface areas. In a star topology, the digital interface of the flexible tactile sensing chip 2 of each electronic skin module is connected to multiple digital interfaces of the main controller. The main controller acts as the central node to manage all skin modules. The star topology has low data transmission latency, and the failure of a single module does not affect the operation of other modules, suitable for large-area, multi-regional body surface coverage requirements.

[0051] Each cascaded electronic skin module is configured with a unique address identifier, which is implemented through hardware configuration or software programming. In the hardware configuration method, each electronic skin module's flexible tactile sensing chip 2 has a reserved address configuration pin. Different voltage levels are set by a combination of external pull-down or pull-up resistors to form a unique address code. In the software programming method, an address configuration command is sent to each electronic skin module via the cascaded link. The command includes the module serial number and the corresponding address code. After receiving the command, the module stores the address code in its internal non-volatile memory. Upon power-up, the module automatically reads the address identifier, which is reflected in the address field of the data frame.

[0052] In this embodiment, when multiple electronic skin modules are cascaded, master and slave nodes can be identified by address identifiers. The master node reads data from the slave nodes via polling. Specifically, the highest bit or a preset segment of the address identifier serves as the master / slave identifier. When the identifier bit is at a preset high level, the corresponding module is designated as the master node; when the identifier bit is at a preset low level, the corresponding module is designated as a slave node. The address code of the master node is unique among all cascaded modules and has a higher priority than that of the slave nodes. Only one master node is configured in a cascaded network, and the rest are slave nodes. When the master node is fixed through hardware configuration, the resistor combination of the address configuration pin is a preset unique combination; when set through software programming, the address configuration instruction sent by the main controller includes a master / slave identifier field, specifying a single electronic skin module as the master node and the remaining electronic skin modules as slave nodes.

[0053] When the master node reads data from the slave nodes, it traverses the entire cascaded link using an address scanning command, identifying the address identifiers of all slave nodes. A polling list of slave nodes is generated in ascending order of address encoding and stored in the master node's temporary buffer. The master node then sends read commands with address identifiers to each slave node sequentially, according to the polling list. The read command includes the master node address, the target slave node address, and the required data length. It is transmitted via the cascaded link's data line. All nodes receive the command, but only the slave node whose address matches the target slave node address responds; the others remain silent. Upon receiving the read command, the selected slave node packages its buffered tactile data into a preset format. The data frame includes the slave node address, data acquisition timestamp, tactile data fields, and verification fields, and is then fed back to the master node via the cascaded link.

[0054] After receiving feedback data from all slave nodes, the master node organizes and sorts the data according to the polling order, supplementing it with tactile data collected by the master node itself to form a complete regional tactile dataset. The master node performs preliminary verification of the dataset, removing invalid and duplicate data, and then transmits the integrated dataset to the embodied agent through a cascaded link. The master node can dynamically adjust the polling cycle according to the number of slave nodes and the amount of data. When a slave node is added or removed from the cascaded network, the master node regenerates the polling list and adjusts the polling interval. The polling interval of a single slave node does not exceed 5 milliseconds, and the data update frequency of the entire network is not less than 20 Hz, meeting the real-time requirements of large-area tactile perception.

[0055] The tactile sensing network can be expanded via hot-swapping. When a new electronic skin module is added, it can be connected to the cascade link. The main controller identifies the new module through periodic address scanning commands, automatically assigns unused address identifiers, and updates the network configuration without requiring a system restart. The tactile sensing of the existing modules remains unaffected during the expansion process. The cascade link is powered by a distributed power supply, with each electronic skin module powered by an independent power module, preventing the cascade network from collapsing due to a power failure in a single module.

[0056] It should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This way of describing the specification is only for clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

[0057] The detailed descriptions listed above are merely specific descriptions of feasible embodiments of the present invention, and are not intended to limit the scope of protection of the present invention. All equivalent embodiments or modifications made without departing from the spirit of the present invention should be included within the scope of protection of the present invention.

Claims

1. A flexible tactile sensing chip for embodied intelligence, characterized in that, At least including: The control processor is used to generate the scanning control timing, process the digital signal output by the analog-to-digital converter to obtain tactile data, and output it to the digital interface. A multiplexer is used to enable signal selection between the tactile sensor and the internal signal bus of the chip, and output analog signals to the analog-to-digital converter. The multiplexer includes row selection channels and column selection channels. Each row selection channel and column selection channel is implemented by a tri-state group, which includes three states: high impedance, medium impedance, and low impedance. The high impedance state is used to cut off the signal path between channels, and the medium impedance and low impedance states are used to enable signal selection between channels. An analog-to-digital converter is used to convert analog signals output from a multiplexer into digital signals and output them to a control processor. A digital interface is used to receive tactile data from the control processor and output it to the embodied intelligent agent; The control processor applies three discrete voltages to the three-state group according to the scan control timing to achieve switching between high-resistance, medium-resistance and low-resistance states.

2. The flexible tactile sensing chip for embodied intelligence according to claim 1, characterized in that, When the voltage applied by the control processor to the tri-state group equals the first voltage, the tri-state group is in a high-resistance state, and the resistance of the tri-state group is greater than or equal to the first resistance. When the voltage applied by the control processor to the tri-state group equals the second voltage, the tri-state group is in a medium-resistance state, and the first resistance is greater than or equal to the resistance of the tri-state group, which in turn is greater than or equal to the second resistance. When the voltage applied by the control processor to the tri-state device equals the third voltage, the tri-state group is in a low-resistance state, and the resistance of the tri-state device is less than or equal to the third resistance. Wherein, the first resistance > the second resistance > the third resistance.

3. The flexible tactile sensing chip for embodied intelligence according to claim 1, characterized in that, The tri-state group includes at least a tri-state device and a switching transistor connected to the tri-state device.

4. The flexible tactile sensing chip according to claim 3, characterized in that, The tri-state group also includes a transimpedance amplifier connected between the tri-state device and the switching transistor.

5. The flexible tactile sensing chip according to claim 1, characterized in that, The flexible tactile sensing chip also includes a signal conditioning circuit, which integrates an amplifier and a virtual ground generation circuit. The amplifier is used to receive and amplify the analog signal output by the multiplexer, and output the amplified analog signal to the analog-to-digital converter. The virtual ground generation circuit is used to provide a reference potential for unselected row or column gating channels.

6. An electronic skin module for embodied intelligence, characterized in that, The electronic skin module includes a flexible sensing layer and a flexible tactile sensing chip as described in any one of claims 1-5. The flexible sensing layer is used to collect tactile signals from the embodied intelligent agent and output them to the flexible tactile sensing chip. The flexible tactile sensing chip is connected to the main controller of the embodied intelligent agent to form an interaction link.

7. The electronic skin module for embodied intelligence according to claim 6, characterized in that, Multiple electronic skin modules are cascaded and expanded through the digital interface of the flexible tactile sensing chip to form a large-area tactile sensing network.

8. The electronic skin module for embodied intelligence according to claim 7, characterized in that, When multiple electronic skin modules are cascaded, master and slave nodes are defined by address configuration, and the master node reads data from the slave node in a round-robin manner.

9. The electronic skin module for embodied intelligence according to claim 5, characterized in that, The flexible sensing layer is a flexible thin-film piezoresistive array sensor with M rows and N columns, where M and N are both positive integers.

10. The electronic skin module for embodied intelligence according to claim 5, characterized in that, The substrate of the flexible sensing layer is a polyimide film.

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