Hand bionic nerve high-density array type flexible electrode facing tactile feedback

Abstract

The invention discloses a hand bionic nerve high-density array type flexible electrode for tactile feedback, belongs to the field of electrical stimulation, and aims to solve the problems of an existing tactile feedback system. The sensor comprises a flexible bottom layer and a high-density electrode matrix, wherein the high-density electrode matrix is prepared on the flexible bottom layer; the flexible bottom layer is in a hand-imitating shape and is divided into a palm area and a finger area. The high-density electrode matrix comprises a plurality of electrode net units, the plurality of electrode net units are distributed in a palm area and a finger area, and local electrical stimulation on different areas is realized by performing current control on the different areas.

Description

Technical Field

[0001] The invention relates to an electrode structure for electrical stimulation and belongs to the field of electrical stimulation. Background Art

[0002] In recent years, with the rapid development of virtual reality (VR), augmented reality (AR) and robot bionics, tactile feedback technology has received widespread attention. Traditional tactile feedback devices mostly rely on a single tactile feedback method such as vibration motors and piezoelectric devices, which are mainly used to simulate the hardness, vibration and touch of objects. However, this type of technology still has many shortcomings in application, especially in delicate tactile and complex motion control scenarios. The following are the main levels of existing tactile feedback technology and the problems that exist:

[0003] Existing tactile feedback systems can be roughly divided into the following categories:

[0004] 1. Vibration feedback system: Vibration motors are used to simulate touch, which is widely used in mobile phones, game controllers and other devices. However, vibration feedback can only provide rough tactile information, such as tapping, vibration, etc., and cannot accurately simulate the texture, shape or complex force feedback of objects.

[0005] 2. Piezoelectric feedback system: This system provides tactile feedback through the deformation of piezoelectric materials. This type of system can provide relatively accurate tactile signals and is suitable for feedback in a smaller range, such as touch screen devices. However, its physical structure limits the area and complexity of feedback, making it difficult to cover a larger area of ​​the hand.

[0006] 3. Mechanical feedback devices: Provide physical force feedback through external mechanical structures, such as force feedback gloves or exoskeleton systems. Although such devices can simulate a more realistic force sensation, they are usually bulky and inconvenient to wear due to the limitations of the mechanical structure, and cannot be used flexibly and widely in daily life, especially in complex virtual environment interactions. It is difficult to provide a natural tactile experience.

[0007] Defects of existing technologies. Although existing tactile feedback technologies have achieved initial success in certain application scenarios, they still have obvious limitations in the following aspects:

[0008] 1. Limited coverage: Most tactile feedback devices can only focus on a small area of ​​the palm or fingers, making it difficult to achieve fine tactile feedback on the entire hand. The delicate tactile experience of the hand depends on large-area, multi-point electrode coverage, and existing systems usually cannot provide consistent feedback effects across the entire palm and finger area.

[0009] 2. Insufficient feedback accuracy: Existing vibration or piezoelectric feedback devices often lack the necessary accuracy and details when simulating fine touch (such as surface texture and object shape). Especially when it is necessary to simulate complex tactile changes or force transmission, the response capabilities of these devices are particularly insufficient and cannot provide users with realistic tactile perception.

[0010] 3. Poor dynamic adaptability: Many existing tactile feedback systems will significantly reduce the feedback effect when the hand moves or the posture changes. Especially at the joints of the fingers, it is difficult to ensure high-quality electrical stimulation due to poor contact of electrodes or sensors. This problem greatly affects the user experience in daily applications, especially in virtual reality applications that require flexible hand movements, and cannot provide continuous and accurate tactile feedback.

[0011] 4. The equipment is bulky and not portable: Although mechanical force feedback devices can simulate a certain degree of realistic tactile sensation, they are large in size, complex in structure, and inconvenient to wear, making them unsuitable for long-term use or high mobility scenarios. At the same time, external mechanical force feedback is difficult to simulate subtle tactile perception, and cannot provide detailed feedback based on neuromuscular control.

[0012] 5. Insufficient real-time feedback: Some existing tactile feedback devices have a slow response speed, especially in complex interactive environments, and it is difficult to achieve dynamic adjustment of real-time tactile feedback. This limits the user's immersive experience in fast interactions and makes it impossible to truly perceive subtle changes in objects or environments.

[0013] In summary, due to the above deficiencies in the prior art, it is difficult for tactile feedback devices to meet the following requirements in practical applications:

[0014] 1. Fine tactile feedback with full coverage of the hand: Existing technologies cannot achieve full coverage of the hand and multi-point precise electrical stimulation feedback, especially in the complex parts of the fingers and palms, and cannot provide flexible and continuous tactile information.

[0015] 2. High-precision tactile perception and force feedback: Existing devices are insufficient in force transmission and fine touch simulation, and cannot meet the needs of applications that require high-precision feedback, such as bionic hands and fine object manipulation.

[0016] 3. Electrode contact stability to adapt to dynamic hand movements: Existing electrode systems are prone to poor contact and feedback signal attenuation during dynamic hand movements, and cannot guarantee continuous tactile feedback effects.

[0017] 4. Lightweight and portable design: Traditional force feedback gloves and mechanical devices are still too bulky in design and cannot meet the requirements of portability and daily use, especially for long-term wearing experience. Summary of the invention

[0018] In view of the problems existing in the existing tactile feedback system, the present invention provides a high-density array flexible electrode for hand bionic nerves for tactile feedback. The present invention can provide dynamic tactile feedback for the entire hand through a high-density array flexible electrode system, combined with hand neurobionic technology and full coverage design. This design ensures high-precision tactile simulation and dynamic adaptability while maintaining light weight and portability, solving the defects of the existing tactile feedback system in terms of coverage, feedback accuracy, motion adaptability and wearing comfort.

[0019] The hand bionic nerve high-density array flexible electrode for tactile feedback of the present invention comprises a flexible bottom layer 100 and a high-density electrode matrix, wherein the high-density electrode matrix is ​​prepared on the flexible bottom layer 100;

[0020] The flexible bottom layer 100 is shaped like a hand and is divided into a palm area and a finger area; the high-density electrode matrix includes a plurality of electrode mesh units, which are distributed in the palm area and the finger area. By controlling the current in different areas, local electrical stimulation of different areas can be achieved.

[0021] Preferably, the palm area includes the base of the palm area, the thenar area and the hypothenar area; the finger area includes the knuckle area and the finger pad area.

[0022] Preferably, the high-density electrode matrix is ​​constructed by N button-type contact electrodes, and the button-type contact electrode is composed of an outer electrode A and an inner electrode B. The outer electrode A is a ring structure with a gap, and the gap is 1 / 4 to 1 / 3 of the whole ring. The inner electrode B is a disc electrode, and the outer electrode A concentrically surrounds the outside of the inner electrode B;

[0023] N outer electrodes A are connected to the first N-channel control terminal CON1, and N inner electrodes B are connected to the second N-channel control terminal CON2. The first N-channel control terminal CON1 and the second N-channel control terminal CON2 are respectively connected to the two ends of a DC power supply, so that a potential difference is formed between the outer electrode A and the inner electrode B of each button-type contact to achieve electrical stimulation of the point.

[0024] Preferably, the first N-channel control terminal CON1 and the second N-channel control terminal CON2 are connected to the positive and negative poles or the negative and positive poles of a DC power source, respectively.

[0025] Preferably, the switches of each channel of the first N-channel control terminal CON1 and the second N-channel control terminal CON2 are independently controlled to achieve electrical stimulation of any area individually.

[0026] Preferably, the flexible bottom layer 100 is a printed circuit board FPC made of a flexible insulating substrate, specifically including a hydrogel layer 101, a PI layer 102, a copper foil layer 103 and a non-woven fabric layer 104. The PI layer 102 is prepared on the non-woven fabric layer 104, and a button-type contact electrode is prepared on the PI layer 102 using the copper foil layer 103, and is adhered to the human skin through the hydrogel layer 101.

[0027] Preferably, it also includes a plurality of fixing holes for wrapping the array-type flexible electrodes around the hand and wearing them.

[0028] Preferably, N=16-256.

[0029] Preferably, each knuckle region includes at least 4 pairs of button-type contact electrodes, and each fingertip region includes at least 9 pairs of button-type contact electrodes.

[0030] Beneficial effects of the invention: The invention provides a tactile feedback glove system based on high-density flexible electrodes, which effectively solves the problems of limited coverage, insufficient feedback accuracy, poor dynamic adaptability and bulky equipment in the prior art, and has significant technical advantages and innovations, which are specifically manifested in the following aspects:

[0031] 1. High-density tactile feedback covering the entire hand

[0032] The electrode system of the present invention includes 193 electrodes distributed in the palm, fingers and joint areas, forming a tactile feedback network with high-density coverage of the entire hand. Compared with the design in the prior art that can only cover local areas, the present invention can provide fine and uniform electrical stimulation throughout the hand, thereby achieving a full coverage tactile feedback experience for the hand. Through the precise control of multi-point electrodes, users can perceive subtle tactile changes in different parts, such as texture, pressure and force feedback, which is particularly prominent in virtual reality applications.

[0033] 2. High-precision, adjustable electrical stimulation parameters

[0034] The present invention achieves fine adjustment of multiple tactile feedbacks through precise electrical stimulation control, which is significantly better than the tactile feedback devices in the prior art. The main performance indicators of the electrical stimulation system are as follows:

[0035] Current range: 0~65.536mA, minimum resolution is 0.256mA, which can provide highly adjustable current intensity according to different tactile needs. Smaller resolution allows more refined electrical stimulation control, ensuring comfort and feedback accuracy in different tactile simulation scenarios.

[0036] Frequency range: 1~255Hz, the frequency of electrical stimulation can be flexibly adjusted to suit different application scenarios. For example, at high frequencies, the system can simulate vibration and surface roughness; at low frequencies, it can provide more realistic force and pressure feedback.

[0037] Pulse width range: 0-510μs, allowing the electrodes to conduct current at different pulse widths to simulate different types of neural stimulation or tactile feedback. This range can precisely control the activation time of each electrode, thereby providing fine tactile perception.

[0038] 3. Dynamic adaptability and electrode contact stability

[0039] The present invention adopts flexible electrode materials and high-density array design to ensure that the electrodes can still maintain good contact during dynamic hand movements, avoiding the signal attenuation problem caused by poor electrode contact in the prior art. The flexible substrate can fit the curve of the hand, and even in complex hand movements (such as grasping, knuckle bending), the stability of the electrode can be maintained to ensure a continuous electrical stimulation effect. By cooperating with the control module, the system can adjust the electrical stimulation parameters in real time to achieve dynamic adaptation and feedback regulation of different areas of the hand.

[0040] 4. Closed-loop control and personalized adjustment

[0041] The present invention has a closed-loop feedback control system that can dynamically adjust the electrical stimulation parameters according to the hand movements or muscle signals fed back by the sensor to ensure the real-time and effectiveness of the tactile feedback. Compared with the existing technology that cannot adjust the intensity and frequency of electrical stimulation in real time, this system can provide a personalized tactile experience in virtual reality, augmented reality and rehabilitation training. For example, the system can automatically adjust the intensity of tactile feedback according to the user's grip strength, allowing the user to feel the hardness and surface characteristics of different objects.

[0042] 5. Lightweight design and portability

[0043] Compared with existing mechanical force feedback devices, the flexible electrode system of the present invention uses lightweight materials and has good wearing comfort. Since the system abandons the complex mechanical structure, the weight of the device is significantly reduced, so that users can wear it for a long time, which is suitable for portable applications, especially for scenes with high mobility requirements, such as virtual reality games, remote control and bionic hand operation.

[0044] 6. Refined tactile simulation

[0045] The present invention can realize refined tactile feedback according to different application requirements, ranging from weak surface vibration perception to strong force feedback. Especially in bionic hands, virtual reality tactile interaction and rehabilitation training, the system can perceive various subtle tactile changes in the environment according to the user's real-time operation, including surface texture, hardness and shape of objects, so that users can get a more realistic interactive experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 It is a schematic diagram of the appearance structure of the hand bionic nerve high-density array flexible electrode for tactile feedback according to the present invention;

[0047] Figure 2 It is a general schematic diagram of the hand bionic nerve high-density array flexible electrode for tactile feedback according to the present invention;

[0048] Figure 3 It is a schematic diagram of the structure of a button-type contact electrode;

[0049] Figure 4 It is the working principle diagram of button-type contact electrode;

[0050] Figure 5 It is a schematic diagram of matrix channel expansion of high-density electrode matrix;

[0051] Figure 6 It is a schematic diagram of the flexible bottom layer distribution. DETAILED DESCRIPTION

[0052] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0053] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0054] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, but they are not intended to limit the present invention.

[0055] Specific implementation method 1: The following is combined Figures 1 to 6 This embodiment is described. The hand bionic nerve high-density array flexible electrode for tactile feedback described in this embodiment includes a flexible bottom layer 100 and a high-density electrode matrix. The high-density electrode matrix is ​​prepared on the flexible bottom layer 100.

[0056] The flexible bottom layer 100 is shaped like a hand and is divided into a palm area and a finger area; the high-density electrode matrix includes a plurality of electrode mesh units, which are distributed in the palm area and the finger area. By controlling the current in different areas, local electrical stimulation of different areas can be achieved.

[0057] The flexible bottom layer 100 is a printed circuit board FPC made of a flexible insulating substrate, specifically including a hydrogel layer 101, a PI layer 102, a copper foil layer 103 and a non-woven fabric layer 104. The PI layer 102 is prepared on the non-woven fabric layer 104, and a button-type contact electrode is prepared on the PI layer 102 using the copper foil layer 103, and is adhered to the human skin through the hydrogel layer 101.

[0058] The electrode array on the flexible bottom layer 100 is distributed in a high-density matrix. The electrode arrangement of the system adopts a matrix structure, which allows precise current control of different areas of the palm and fingers. Multiple small electrodes are arranged closely to provide local electrical stimulation according to the needs of different locations. The high-density matrix distribution covers the palm area and the finger area, see Figure 1 and Figure 2 :

[0059] The palm area includes the base of the palm, thenar and hypothenar areas; the electrodes are arranged in the center and proximal side of the palm (close to the wrist), and the electrodes in this area are mainly used to stimulate or monitor nerve and muscle activity in the palm. The electrodes are evenly distributed, covering the main areas of the lower part of the thumb, the base of the palm and the palm.

[0060] The finger area includes the knuckle area and the finger pad area. Each finger is covered with multiple pairs of electrodes, which are distributed in the joints of the fingers (proximal interphalangeal joints and distal interphalangeal joints) and the finger pads, which can provide accurate fingertip tactile feedback. Each knuckle area contains at least 4 pairs of button-type contact electrodes, and each finger pad area contains at least 9 pairs of button-type contact electrodes. Distributed in different positions of the knuckles and finger pads, users can perceive delicate touch and pressure changes in the virtual environment, and achieve high-density electrode coverage on the area to be stimulated. Since the thumb area is a knuckle, a higher-density electrode network is specially designed to cover the thumb pad, knuckles and the palmar muscle area below it, to adapt to the key role of the thumb in multi-directional movements, and provide more accurate tactile feedback and force perception.

[0061] See also Figure 3 As shown, the high-density electrode matrix is ​​constructed by N button-type contact electrodes, and the button-type contact electrode is composed of an outer electrode A and an inner electrode B. The outer electrode A is a ring structure with a gap, and the gap is 1 / 4 to 1 / 3 of the whole ring. The inner electrode B is a disc electrode, and the outer electrode A concentrically surrounds the outside of the inner electrode B;

[0062] N outer electrodes A are connected to the first N-channel control terminal CON1, and N inner electrodes B are connected to the second N-channel control terminal CON2. The first N-channel control terminal CON1 and the second N-channel control terminal CON2 are respectively connected to the two ends of a DC power supply, so that a potential difference is formed between the outer electrode A and the inner electrode B of each button-type contact to achieve electrical stimulation of the point.

[0063] See also Figure 4 As shown, the first N-channel control terminal CON1 and the second N-channel control terminal CON2 are connected to the positive and negative poles or the negative and positive poles of the DC power supply respectively. The control system can alternately apply positive and negative voltages between the N outer electrodes A and the N inner electrodes B by reverse switching of the potential, thereby achieving bidirectional current stimulation.

[0064] The switches of each channel of the first N-channel control terminal CON1 and the second N-channel control terminal CON2 are independently controlled to achieve electrical stimulation of any area individually.

[0065] according to Figure 4 The arrangement of the button-type contact electrodes and the internal circuit connection shown support channel expansion, N = 16 to 256. The solution can expand the 32-channel electrical stimulator to 256 channels in the form of a matrix arrangement, and can expand the number of channels at a minimum cost. Figure 1 and Figure 2 The electrode patch shown in the figure uses 193 of these channels. By arranging the electrodes in a matrix form according to the distribution of nerves in the hand, precise electrical stimulation that fully covers the hand can be achieved.

[0066] It also includes multiple fixing holes for wrapping the array of flexible electrodes around the hand. The fixing holes are present in all locations where additional fixing may be required. Leaving these holes can facilitate the assembly of the electrode stickers on the gloves, and can also be used for the recommended wrapping and wearing when there are no gloves to assemble. The fixing holes are additionally rounded to ensure their strength and reliability and are not easily damaged.

[0067] The material of the flexible bottom layer 100 is a printed circuit board (FPC) made of a flexible insulating substrate. The button-type contacts can directly contact the human body or be attached with hydrogel. It can be bent, rolled, and folded freely, and can be arranged arbitrarily according to the spatial layout requirements, and can be moved and stretched arbitrarily in three-dimensional space to fit the shape of the palm. The rounded corners are processed everywhere to enhance the wear resistance of the material and improve the service life.

[0068] Through these high-density electrodes, the system can simulate various tactile feedback for applications in virtual reality, augmented reality, or prosthetic control, helping users perceive objects or forces in virtual or remote environments. This may involve tactile simulation (such as texture, pressure) as well as force feedback.

[0069] Although the present invention is described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the present invention. It should therefore be understood that many modifications may be made to the exemplary embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that the various dependent claims and features described herein may be combined in a manner different from that described in the original claims. It will also be understood that the features described in conjunction with a single embodiment may be used in other described embodiments.

Claims

1. A high-density array flexible electrode for hand bionic nerves for tactile feedback, characterized in that: It comprises a flexible bottom layer (100) and a high-density electrode matrix, wherein the high-density electrode matrix is ​​prepared on the flexible bottom layer (100); The flexible bottom layer (100) is shaped like a hand and is divided into a palm area and a finger area; the high-density electrode matrix comprises a plurality of electrode mesh units, and the plurality of electrode mesh units are distributed in the palm area and the finger area, and local electrical stimulation of different areas is achieved by controlling the current in different areas.

2. The hand bionic nerve high-density array flexible electrode for tactile feedback according to claim 1, characterized in that: The palm area includes the base of the palm, thenar and hypothenar areas; the finger area includes the knuckle area and finger pad area.

3. The hand bionic nerve high-density array flexible electrode for tactile feedback according to claim 2, characterized in that: The high-density electrode matrix is ​​constructed by N button-type contact electrodes, which are composed of an outer electrode A and an inner electrode B. The outer electrode A is a ring structure with a gap, and the gap is 1 / 4 to 1 / 3 of the whole ring. The inner electrode B is a disc electrode, and the outer electrode A concentrically surrounds the outside of the inner electrode B. N outer electrodes A are connected to the first N-channel control terminal CON1, and N inner electrodes B are connected to the second N-channel control terminal CON2. The first N-channel control terminal CON1 and the second N-channel control terminal CON2 are respectively connected to the two ends of a DC power supply, so that a potential difference is formed between the outer electrode A and the inner electrode B of each button-type contact to achieve electrical stimulation of the point.

4. The hand bionic nerve high-density array flexible electrode for tactile feedback according to claim 3, characterized in that: The first N-channel control terminal CON1 and the second N-channel control terminal CON2 are respectively connected to the positive and negative poles or the negative and positive poles of the DC power supply.

5. The hand bionic nerve high-density array flexible electrode for tactile feedback according to claim 3, characterized in that: The switches of each channel of the first N-channel control terminal CON1 and the second N-channel control terminal CON2 are independently controlled to achieve electrical stimulation of any area individually.

6. The hand bionic nerve high-density array flexible electrode for tactile feedback according to claim 1, characterized in that: The flexible bottom layer (100) is a printed circuit board (FPC) made of a flexible insulating substrate, specifically comprising a hydrogel layer (101), a PI layer (102), a copper foil layer (103) and a non-woven fabric layer (104); the PI layer (102) is prepared on the non-woven fabric layer (104); a button-type contact electrode is prepared on the PI layer (102) using the copper foil layer (103), and is adhered to human skin via the hydrogel layer (101).

7. The hand bionic nerve high-density array flexible electrode for tactile feedback according to claim 1, characterized in that: It also includes a plurality of fixing holes for wrapping the array-type flexible electrodes around the hand and wearing them.

8. The hand bionic nerve high-density array flexible electrode for tactile feedback according to claim 1, characterized in that: N＝16～256。 9. The hand bionic nerve high-density array flexible electrode for tactile feedback according to claim 2, characterized in that: Each knuckle region contains at least 4 pairs of button-type contact electrodes, and each fingertip region contains at least 9 pairs of button-type contact electrodes.

Images