Large-area electronic skin sensing system and method applied to robot collision detection

Abstract

This invention discloses a large-area electronic skin sensing system and method for robot collision detection. The system comprises a flexible, conformable tactile sensing array and a data acquisition and processing device. The flexible tactile sensing array includes a pair of flexible substrates, a pressure-sensitive layer encapsulated between the two substrates, and a protective layer outside the flexible substrates. Several equally spaced, parallel electrodes are arranged on the flexible substrates, with the electrodes on the two flexible substrates orthogonally arranged to form an array. The pressure-sensitive layer is connected to the data acquisition and processing device via the electrodes. This invention achieves real-time contact-based tactile sensing, thereby enabling low-cost robot collision detection in practical applications involving human-computer interaction and multi-machine collaboration, ensuring robot operational safety.

Description

Technical Field

[0001] This invention specifically relates to a large-area electronic skin sensing system and method for robot collision detection. Background Technology

[0002] Intelligent robot technology is one of the most promising high-tech advancements today. Based on computer vision, natural language processing, and deep learning, it fuses information from multiple sensors, enabling it to effectively adapt to changing environments and possess strong self-adaptation, learning, and self-decision-making capabilities. Intelligent robots are gradually entering our daily lives, with broad application prospects in industry, healthcare, services, and logistics, replacing humans in performing various tasks. In this context, the robot's safety performance becomes paramount, and its collision detection capabilities directly determine its safety performance.

[0003] In existing technologies, robot collision detection generally employs two methods: contact and non-contact. Contact methods mainly include collision detection based on current loops, joint torque sensors, and electronic skin, while non-contact methods mainly include collision detection based on vision, infrared, and ultrasonic sensors. The aforementioned non-contact collision detection methods are costly, easily affected by environmental factors, and struggle to achieve comprehensive coverage, resulting in poor collision detection performance. In contact collision detection, current loop-based collision detection senses external forces and determines whether a collision has occurred based on the robot's dynamics model and current loop torque feedback information. However, the robot's dynamics model struggles to accurately identify these forces, leading to low sensitivity and reliability. Joint torque sensor-based collision detection directly senses external forces based on feedback information from the joint torque sensor, but torque sensors are expensive and difficult to use in large quantities. Electronic skin-based collision detection senses external forces based on pressure sensors within the robot's electronic skin, but currently, it relies on a single-unit electronic skin sensor, resulting in low spatial resolution and low detection accuracy.

[0004] Electronic skin, due to its flexibility and ease of adhesion to irregular surfaces, shows broad application prospects in the field of intelligent robotics. It can detect external environmental parameters when sensors are in direct contact with the environment, thereby reflecting the status of the external environment and enabling display, transmission, and control. In robot collision detection applications, electronic skin can conformally adhere to and cover the robot surface, achieving omnidirectional coverage and displaying the area where a collision occurred. Therefore, there is an urgent need for a low-cost, high spatial resolution, large-area electronic skin system to achieve omnidirectional robot collision detection and ensure the safe operation of robots. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a large-area electronic skin sensing system and method for robot collision detection, which addresses the above-mentioned defects in the existing technology, so as to realize real-time contact-based tactile perception, thereby achieving low-cost robot collision detection in practical application scenarios of human-computer interaction and multi-machine collaboration, and ensuring the safe operation of robots.

[0006] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows:

[0007] A large-area electronic skin sensing system for robot collision detection is characterized by comprising a flexible, conformable tactile sensor array and a data acquisition and processing device.

[0008] The flexible tactile sensing array includes a pair of flexible substrates, a pressure-sensitive layer encapsulated between the two flexible substrates, and a device protective layer outside the flexible substrates; several equally spaced parallel electrodes are provided on the flexible substrates, and the electrodes on the two flexible substrates are orthogonally arranged to form an array; the non-electrode surface of the flexible substrates is provided with an array of protrusions located above the orthogonal points of the electrodes; the pressure-sensitive layer is connected to a data acquisition and processing device.

[0009] According to the above technical solution, the flexible substrate is a flexible circuit board made of polyimide film; the electrode is a conductive composite made of PI-Ag; the pressure-sensitive layer is made of carburized polyolefin; the device protective layer is a PU film; and the bump array includes solder dots, silicone or UV adhesive.

[0010] According to the above technical solution, the thickness of the PU film used as the protective layer of the device is 0.5-2mm, the width of the electrode is 1-5mm, the spacing between adjacent parallel electrodes is 6-15mm, the diameter of the bump is 1-3mm, and the height is 0.3-0.8mm.

[0011] According to the above technical solution, the flexible substrate and the pressure-sensitive layer are bonded together with low surface energy double-sided adhesive, and then flexibly encapsulated with the device protective layer through a cold pressing process.

[0012] The flexible tactile sensor array and data acquisition and processing device are connected by an externally extended flexible connection film on a custom patterned flexible substrate.

[0013] According to the above technical solution, the preparation method of PI-Ag conductive composite is as follows: silver powder is soaked in anhydrous ethanol, ultrasonically treated, and dried in an oven to obtain usable silver powder; PI solution is dissolved in DMF and stirred thoroughly to obtain PI dilution; usable silver powder is added to PI dilution and stirred to ensure that the silver powder is fully dispersed in the mixed solution; the mixed solution is heated in an oven to evaporate the DMF to dryness to obtain conductive prepolymer; the conductive prepolymer is ground thoroughly in a mortar to obtain the PI-Ag conductive composite.

[0014] According to the above technical solution, in the PI dilution solution, the mass ratio of PI solution to DMF is 1:0.5-1; the mass of PI in the mixed solution is 1 / 3-1 / 2 of Ag.

[0015] According to the above technical solution, the data acquisition and processing device includes a power management module, an array index module, a digital-to-analog converter module, an MCU module, a status output module, and a data transmission unit. The MCU module is connected to the power management module, the array index module, the status output module, and the data transmission unit. The array index module is connected to the MCU module and the status output module through the digital-to-analog converter module. The status output module is used to connect to the robot, the data transmission unit is used to connect to the computer terminal, and the array index module is connected to the flexible tactile sensor array of the electronic skin.

[0016] According to the above technical solution, the data acquisition and processing device adopts a ground-based circuit architecture to achieve potential shielding, thereby acquiring signals from each sensing unit of the flexible tactile sensing array and reducing signal crosstalk.

[0017] The power management module provides power to the data acquisition and processing device and the flexible tactile sensing array; the array index module includes an m:1 analog switch and an n-way bidirectional integrated switch to achieve orderly acquisition of signals from the flexible tactile sensing array.

[0018] The data acquisition and processing device is configured through an array index module, with a maximum size of 32×32. The sampling frequency of the data acquisition and processing device is related to the refresh frequency of the flexible tactile sensing array and the response time of collision detection. Its sampling frequency for a single sensing unit can reach 20000Hz.

[0019] According to the above technical solution, the fabrication method of the flexible tactile sensing array includes the following steps:

[0020] S1, Prepare a flexible substrate with custom patterned electrodes: Attach a mask with a cut pattern to the flexible substrate, apply a conductive composite to the mask, remove the mask, and place the entire substrate in an oven for heating and curing to obtain a flexible substrate with integrated electrodes.

[0021] S2, take a flexible substrate with transverse electrodes as the upper substrate, and integrate a solidified bump array above the electrode intersection point on its non-electrode surface by printing or printing method.

[0022] S3, a pair of flexible substrates and pressure-sensitive layers are bonded together in a specific order using low surface energy double-sided adhesive, and then flexibly encapsulated with a device protective layer through a cold pressing process to obtain a flexible tactile sensing array.

[0023] A collision detection method using the large-area electronic skin sensing system for robot collision detection described above includes the following steps:

[0024] Step 1: Establish a large-area electronic skin sensing system for robot collision detection;

[0025] Step 2: When the robot is working normally, the electronic skin sensor array covering the surface of each axis of the robot senses the surrounding environment of the robot in real time. The data acquisition and processing device converts the tactile perception signals of each electronic skin into analog and digital signals in real time and calculates and outputs the current state of the system to control the movement of the robot.

[0026] Step 3: The large-area electronic skin sensing system determines in real time whether the robot has collided with anything.

[0027] Step 4: Transmit the signal data of the flexible tactile sensor array to the computer terminal in real time;

[0028] In step 3, the specific process of determining whether the robot has collided in real time using a large-area motor skin is as follows:

[0029] Step 3-1, System Initialization Phase: The average value of the flexible tactile sensor array signals collected by the data acquisition and processing device for the first k frames is used as the robot's initial state reference V. base ;

[0030] Step 3-2: The data acquisition and processing device systematically stores the acquired flexible tactile sensor array signals. The sensor array signal acquired at the previous moment is V. t-1 The sensor array signal acquired at the current moment is V. t Calculate V respectively base With V t-1 The Euclidean distance between them +1 and V t-1 With V t The Euclidean distance between them +1 is last_dis and now_dis; the collision coefficient collision_ratio is calculated by dividing the smaller of last_dis and now_dis by the larger of them; a threshold COLL_THRESHOLD is set, and when the collision_ratio is less than COLL_THRESHOLD, it is determined that the robot has collided and the robot is controlled to stop working.

[0031] Step 3-3: Wherever the large-area electronic skin sensing system calculates a collision coefficient exceeding the threshold, it determines that the robot has collided, thereby controlling the robot to stop working.

[0032] The present invention has the following beneficial effects:

[0033] 1. This invention is a lightweight, low-cost, flexible, and bendable large-area electronic skin sensing system for collision detection that can conformally adhere to and cover the surface of a robot. Compared with traditional detection methods and sensing technologies, this invention applies a large-area electronic skin system with high spatial resolution to robot collision detection, realizing real-time contact-based tactile perception. This enables low-cost robot collision detection in practical application scenarios such as interpersonal communication and multi-machine collaboration, ensuring the safe operation of robots.

[0034] 2. The method for preparing a flexible tactile sensor array provided by the present invention organically combines the processing technology of flexible circuit boards made of highly mature polyimide film material with screen printing technology, providing a simple and efficient method for preparing a flexible tactile sensor array that can meet the needs of large-scale preparation of large-area electronic skin.

[0035] 3. The large-area electronic skin sensing system provided by this invention greatly simplifies the connection between the flexible tactile sensing array and the data acquisition and processing device through the orthogonal electrode structure of the flexible tactile sensing array and the array index module of the data acquisition and processing device, achieving orderly acquisition of sensing array signals. Simultaneously, the data acquisition and processing device achieves potential shielding based on a grounded circuit architecture, reducing signal crosstalk. The large-area electronic skin sensing system disclosed in this invention is not only lightweight and low-cost, but also allows for customized large-area electronic skin sensing systems for different regions by modifying the shape and area of ​​the flexible substrate, the number, spacing, and width of the electrodes in the electrode group, and configuring the array index module of the data acquisition and processing device. This system can also accurately identify the distribution of pressure.

[0036] 4. The large-area electronic skin sensing system disclosed in this invention converts external pressure signals into resistance signals to sense external pressure, while also possessing the ability of longitudinal elastic deformation to meet the flexibility requirements of electronic skin. Furthermore, it can adapt to different types of robots by integrating multiple large-area electronic skin sensing systems in parallel, conformally attaching to and covering the robot's outer surface to sense the external environment and achieve collision detection. When applied to robot collision detection, the large-area electronic skin sensing system provided by this invention has a simple data processing method and can achieve robot collision detection. It uses the ratio of data change distances instead of simply judging the distance of data changes, thus having a certain adaptability to the unstructured environment in which robots operate. At the same time, the computational complexity of this detection method is low, and improving sampling efficiency can reduce the detection time interval. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the flexible tactile sensing array in an embodiment of the present invention;

[0038] Figure 2This is a schematic diagram of the fabrication process of the flexible tactile sensing array in an embodiment of the present invention;

[0039] Figure 3 This is a schematic diagram of the circuit principle of the data acquisition and processing device in an embodiment of the present invention;

[0040] Figure 4 This is a flowchart of the collision detection method of the large-area electronic skin sensing system in an embodiment of the present invention;

[0041] Figure 5 This is a schematic diagram of the integration of a multi-module large-area electronic skin sensing system in an embodiment of the present invention.

[0042] In the figure, 1-flexible tactile sensing array, 11-flexible substrate, 111-electrode, 112-bump array, 12-pressure sensitive layer, 13-device protective layer; 2-data acquisition and processing device; 301-flexible FPC substrate made of polyimide film; 302-template printed patterned electrode; 303-flexible substrate with several equally spaced parallel electrodes; 304-patterned bump array by printing or printing method; 305-flexible substrate with several equally spaced parallel electrodes and bump array; 306-flexible tactile sensing array. Detailed Implementation

[0043] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0044] Reference Figures 1-5 As shown, an embodiment 1 of the present invention provides a large-area electronic skin sensing system for robot collision detection, comprising a flexible, conformable tactile sensor array and a data acquisition and processing device.

[0045] The flexible tactile sensing array includes a pair of flexible substrates, a pressure-sensitive layer encapsulated between the two flexible substrates, and a device protective layer outside the flexible substrates; several equally spaced parallel electrodes are provided on the flexible substrates, and the electrodes on the two flexible substrates are orthogonally arranged to form an array; the non-electrode surface of the flexible substrates is provided with an array of protrusions located above the orthogonal points of the electrodes; the pressure-sensitive layer is connected to a data acquisition and processing device through electrodes.

[0046] The robot collision detection method provided by this invention has significant characteristic indicators that distinguish between normal robot operation and collisions, thus enabling early detection of changes in the robot's motion state and achieving collision detection functionality. In this embodiment, a piezoresistive tactile sensor array is selected, but in practical applications, it is not limited to piezoresistive tactile sensor arrays. Other flexible tactile sensor arrays based on capacitance, piezoelectricity, and strain principles can also be used to achieve robot collision detection using the method described above. That is, it can be directly applied to other array-type pressure sensors. This provides new ideas and inspiration for robots to achieve collision detection and human-computer interaction capabilities by attaching and covering the robot's outer surface with electronic skin.

[0047] Furthermore, the flexible substrate is a flexible circuit board made of polyimide film; the electrodes are conductive composites made of PI-Ag; the pressure-sensitive layer is made of carburized polyolefin; the device protective layer is a PU film; and the bump array includes solder dots, silicone, or UV adhesive.

[0048] Furthermore, PI-Ag is a polyimide-silver powder conductive polymer.

[0049] Furthermore, the thickness of the PU film serving as the protective layer of the device is 0.5–2 mm, the width of the electrode is 1–5 mm, the spacing between adjacent parallel electrodes is 6–15 mm, the diameter of the bump is 1–3 mm, and the height is 0.3–0.8 mm.

[0050] Furthermore, the flexible substrate and pressure-sensitive layer are bonded together with low surface energy double-sided adhesive and then flexibly encapsulated with the device protective layer through a cold pressing process.

[0051] The flexible tactile sensing array and data acquisition and processing device are connected by an externally extended flexible connection film on a custom patterned flexible substrate; electrodes are also provided on the externally extended flexible connection film, which are connected to the electrodes on the flexible substrate. We usually regard them as pads as connection ports.

[0052] Further, the preparation method of the PI-Ag conductive composite is as follows: silver powder is soaked in anhydrous ethanol, ultrasonically treated, and dried in an oven. This process is repeated 3-5 times to obtain usable silver powder; PI solution is dissolved in DMF and stirred thoroughly to obtain a PI dilution; usable silver powder is added to the PI dilution and stirred to ensure that the silver powder is fully dispersed in the mixed solution; the mixed solution is heated in an oven to evaporate the DMF to dryness, obtaining a conductive prepolymer; the conductive prepolymer is ground thoroughly in a mortar to obtain the PI-Ag conductive composite.

[0053] DMF is N,N-dimethylformamide.

[0054] Furthermore, in the PI dilution solution, the mass ratio of PI solution to DMF is 1:0.5-1; the mass of PI in the mixed solution is 1 / 3-1 / 2 of Ag.

[0055] Furthermore, the data acquisition and processing device includes a power management module, an array index module, a digital-to-analog converter module, an MCU module, a status output module, and a UART data transmission unit. The MCU module is connected to the power management module, the array index module, the status output module, and the UART data transmission unit. The array index module is connected to the MCU module and the status output module via the digital-to-analog converter module. The status output module is used to connect to the robot, the UART data transmission unit is used to connect to the computer terminal, and the array index module is connected to the flexible tactile sensor array of the electronic skin. The MCU module is a low-power computing unit. The status output module converts the system status into relay actions, thereby controlling the robot's movement. The UART module transmits the flexible tactile sensor array signal data to the computer terminal in real time.

[0056] Furthermore, the data acquisition and processing device employs a ground-based circuit architecture to achieve potential shielding (this is a method for acquiring signals from a sensor array; the ground-based circuit architecture means that when a sensor unit in a certain row has a signal, that row is grounded, while the voltage of other rows is set to VREF, thereby shielding the crosstalk of other rows to the sensor unit signals of this row through equal potential). This allows for the acquisition of signals from each sensor unit of the flexible tactile sensor array, reducing signal crosstalk. The flexible substrate of the flexible tactile sensor array has several equally spaced parallel electrodes, and the electrodes on two flexible substrates are orthogonally arranged to form an array; each orthogonal point of the electrodes is a sensor unit.

[0057] The power management module provides power to the data acquisition and processing device and the flexible tactile sensing array; the array index module includes an m:1 analog switch and an n-way bidirectional integrated switch to achieve orderly acquisition of signals from the flexible tactile sensing array.

[0058] The number of channels of the data acquisition and processing device is configured through the array index module, with a maximum of 32×32. The sampling frequency of the data acquisition and processing device is related to the refresh frequency of the flexible tactile sensing array and the response time of collision detection. Its sampling frequency for a single sensing unit can reach 20000Hz.

[0059] Example 2

[0060] like Figure 2 As shown, the fabrication method of the flexible tactile sensing array is further defined based on Example 1.

[0061] Furthermore, the fabrication method of the flexible tactile sensing array includes the following steps:

[0062] S1, Prepare a flexible substrate with customized patterned electrodes and an externally extended flexible connection film: Attach a mask with a cut pattern to the flexible substrate, apply a conductive composite to the mask, remove the mask, and place the entire substrate in an oven at 90-120℃ for 1.5-2 hours to cure, thus obtaining a flexible substrate with integrated electrodes.

[0063] S2, take a flexible substrate with transverse electrodes as the upper substrate, and integrate a solidified bump array above the electrode intersection point on its non-electrode surface by printing or printing method.

[0064] S3 involves bonding a pair of flexible substrates and a pressure-sensitive layer in a specific order using low surface energy double-sided adhesive, and then flexibly encapsulating them with a device protective layer using a cold pressing process to obtain a flexible tactile sensing array.

[0065] Example 3

[0066] like Figure 4 As shown, based on Embodiment 1, the collision detection method of the large-area electronic skin sensing system applied to robot collision detection is further defined.

[0067] A collision detection method using the large-area electronic skin sensing system for robot collision detection described above includes the following steps:

[0068] Step 1: Establish a large-area electronic skin sensing system for robot collision detection;

[0069] Step 2: When the robot is working normally, the electronic skin sensor array covering the surface of each axis of the robot senses the surrounding environment of the robot in real time. The data acquisition and processing device converts the tactile perception signals of each electronic skin into analog and digital signals in real time and calculates and outputs the current state of the system to control the movement of the robot.

[0070] Step 3: The large-area electronic skin sensing system determines in real time whether the robot has collided with anything.

[0071] Step 4: Transmit the signal data of the flexible tactile sensor array to the computer terminal in real time via UART;

[0072] In step 3, the specific process of determining whether the robot has collided in real time using a large-area motor skin is as follows:

[0073] Step 3-1, System Initialization Phase: The average value of the flexible tactile sensor array signals collected by the data acquisition and processing device for the first k frames is used as the robot's initial state reference V. base ;

[0074] Step 3-2: The data acquisition and processing device systematically stores the acquired flexible tactile sensor array signals. The sensor array signal acquired at the previous moment is V. t-1 The sensor array signal acquired at the current moment is V. t Calculate V respectively base With V t-1 The Euclidean distance between them +1 and V t-1 With V t The Euclidean distance between them +1 is last_dis and now_dis; the collision coefficient collision_ratio is calculated by dividing the smaller of last_dis and now_dis by the larger of them; a threshold COLL_THRESHOLD is set, and when collision_ratio is less than COLL_THRESHOLD, it is determined that the robot has collided, the status output module triggers the relay action, and controls the robot to stop working.

[0075] Step 3-3: Configure the large-area electronic skin sensing system on each axis of the robot as "wired AND" logic. That is, no matter where the large-area electronic skin sensing system calculates the collision coefficient and exceeds the threshold, it will determine that the robot has collided, thereby triggering the relay action through the status output module and controlling the robot to stop working.

[0076] In this embodiment, the average value of the first 5 frames of flexible tactile sensor array signals is used as the robot's initial state baseline Vbase; the collision coefficient collision_ratio is used as the final index for collision detection. When the robot is working normally, the collision_ratio approaches 1, and when the robot collides, the collision_ratio decreases sharply.

[0077] Example 4

[0078] Combination Figure 1-3 The specific preparation method of the large-area electronic skin sensing system of the present invention is as follows:

[0079] (1) Preparation of PI-Ag conductive composite: Take 6g of silver powder, soak it in 10ml of anhydrous ethanol, sonicate it for 10min, and dry it in an oven. Repeat this process 3-5 times to obtain usable silver powder. Take 2g of PI solution, dissolve it in 2g of DMF, and stir it thoroughly for 10min to obtain PI dilution. Add the usable silver powder to the PI dilution and stir for 5min to fully disperse the silver powder in the mixed solution. Place the mixed solution in an oven at 60℃ for 10min to evaporate the DMF and obtain conductive prepolymer. Place the conductive prepolymer in a mortar and grind it thoroughly for 30min to obtain the PI-Ag conductive composite.

[0080] (2) Specifications of flexible substrates made of polyimide film: such as Figure 1 The flexible substrate 11 has a size of 10cm×10cm, on which 10 electrodes with a width of 1mm and a spacing of 9mm are arranged in parallel. The externally extended flexible connection film on the flexible substrate has a length of 5cm.

[0081] (3) Configuration of data acquisition and processing device: The data acquisition and processing device is configured as 10×10 channels through the array index module;

[0082] (4) Paste a mask with a cut pattern onto a flexible substrate, apply the conductive composite onto the mask, remove the mask, and place the whole thing into an oven at 90-120℃ for 1.5-2 hours to cure, thus obtaining a flexible substrate for integrated electrodes.

[0083] (5) Take a flexible substrate with transverse electrodes as the upper substrate, and use a 3D direct writing printing device to print a solidified array of bumps with a diameter of 2mm and a height of 0.4mm above the electrode intersection point on the non-electrode surface.

[0084] (6) A pair of flexible substrates and pressure-sensitive layers are bonded together in a specific order using low surface energy double-sided adhesive, and then flexibly encapsulated with the device protective layer through a cold pressing process to obtain a 10×10 flexible tactile sensing array.

[0085] (7) A large-area electronic skin sensing system is obtained by connecting the flexible tactile sensing array and the data acquisition and processing device through an externally extended flexible connection film on a customized patterned flexible substrate.

[0086] The above are merely preferred embodiments of the present invention and should not be construed as limiting the scope of the present invention. Therefore, any equivalent changes made in accordance with the claims of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A collision detection method employing a large-area electronic skin sensing system for robot collision detection, characterized in that, The large-area electronic skin sensing system for robot collision detection includes a flexible, conformable tactile sensor array and a data acquisition and processing device. The flexible tactile sensing array includes a pair of flexible substrates, a pressure-sensitive layer encapsulated between the two flexible substrates, and a device protective layer outside the flexible substrates; the flexible substrates are provided with a number of equally spaced parallel electrodes, and the electrodes on the two flexible substrates are orthogonally arranged to form an array; The pressure-sensitive layer is connected to the data acquisition and processing device; The collision detection method includes the following steps: Step 1: Establish a large-area electronic skin sensing system for robot collision detection; Step 2: When the robot is working normally, the electronic skin sensor array covering the surface of each axis of the robot senses the surrounding environment of the robot in real time. The data acquisition and processing device converts the tactile perception signals of each electronic skin into analog and digital signals in real time and calculates and outputs the current state of the system to control the movement of the robot. Step 3: The large-area electronic skin sensing system determines in real time whether the robot has collided with anything. Step 4: Transmit the signal data of the flexible tactile sensor array to the computer terminal in real time; In step 3, the specific process of the large-area electronic skin determining in real time whether the robot has collided is as follows: Step 3-1, System Initialization Phase: The average value of the flexible tactile sensor array signals collected by the data acquisition and processing device for the first k frames is used as the robot's initial state reference. ; Step 3-2: The data acquisition and processing device systematically stores the acquired flexible tactile sensor array signals. The sensor array signal acquired at the previous moment is... The sensor array signal collected at the current moment is Calculate separately and Euclidean distance between +1 and and The Euclidean distance between them + 1 is , ;by and The collision coefficient is calculated by dividing the smaller of the two by the larger of the two. Set a threshold ,when Less than When a collision occurs, the robot is determined to have collided, and the robot is stopped from operating. Step 3-3: Wherever the large-area electronic skin sensing system calculates a collision coefficient exceeding the threshold, it determines that the robot has collided, thereby controlling the robot to stop working.

2. The collision detection method according to claim 1, characterized in that, The flexible circuit board has a flexible substrate made of polyimide film; the electrodes are made of PI-Ag conductive composite; the pressure-sensitive layer is made of carburized polyolefin; and the device protective layer is made of PU film.

3. The collision detection method according to claim 1, characterized in that, The non-electrode surface of the flexible substrate is provided with a bump array located above the electrode intersection point. The bump array includes solder dots, silicone or UV adhesive.

4. The collision detection method according to claim 1, characterized in that, The flexible substrate and pressure-sensitive layer are bonded together with low surface energy double-sided adhesive and then flexibly encapsulated with the device protective layer through a cold pressing process. The flexible tactile sensor array and data acquisition and processing device are connected by an externally extended flexible connection film on a custom patterned flexible substrate.

5. The collision detection method according to claim 2, characterized in that, The preparation method of PI-Ag conductive composite is as follows: silver powder is soaked in anhydrous ethanol, ultrasonically treated, and dried in an oven to obtain usable silver powder; PI solution is dissolved in DMF and stirred thoroughly to obtain PI dilution; usable silver powder is added to PI dilution and stirred to ensure that the silver powder is fully dispersed in the mixed solution; the mixed solution is heated in an oven to evaporate the DMF to dryness to obtain conductive prepolymer. The conductive prepolymer was ground thoroughly in a mortar to obtain the PI-Ag conductive composite.

6. The collision detection method according to claim 5, characterized in that, In the PI dilution solution, the mass ratio of PI solution to DMF is 1:0.5-1; the mass of PI in the mixed solution is 1 / 3-1 / 2 of Ag.

7. The collision detection method according to claim 1, characterized in that, The data acquisition and processing device includes a power management module, an array index module, a digital-to-analog converter module, an MCU module, a status output module, and a data transmission unit. The MCU module is connected to the power management module, the array index module, the status output module, and the data transmission unit. The array index module is connected to the MCU module and the status output module through the digital-to-analog converter module. The status output module is used to connect to the robot, the data transmission unit is used to connect to the computer terminal, and the array index module is connected to the flexible tactile sensor array of the electronic skin.

8. The collision detection method according to claim 1, characterized in that, The data acquisition and processing device uses a grounded circuit architecture to achieve potential shielding, thereby acquiring signals from each sensing unit of the flexible tactile sensing array and reducing signal crosstalk.

9. The collision detection method according to claim 1, characterized in that, The fabrication method of the flexible tactile sensing array includes the following steps: S1, Prepare a flexible substrate with custom patterned electrodes: Attach a mask with a cut pattern to the flexible substrate, apply a conductive composite to the mask, remove the mask, and place the entire substrate in an oven for heating and curing to obtain a flexible substrate with integrated electrodes. S2, take a flexible substrate with transverse electrodes as the upper substrate, and integrate a solidified bump array above the electrode intersection point on its non-electrode surface by printing or printing method. S3. A pair of flexible substrates and pressure-sensitive layers are bonded together in a predetermined order using low surface energy double-sided adhesive, and then flexibly encapsulated with a device protective layer using a cold pressing process to obtain a flexible tactile sensing array.

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