Tactile feedback glove integrating attitude detection and sensing

Abstract

The invention discloses a tactile feedback glove integrating posture detection and sensing. The tactile feedback glove comprises a glove body, a posture detection module, a sensing module, a feedback module and a control module. The posture detection module comprises an optical fiber and is used for converting stress borne by finger bending into a central wavelength drift distance so as to obtain hand posture information; the sensing module comprises a pressure and temperature dual-mode sensor which is used for measuring pressure according to the capacitance change characteristic of the parallel plate capacitor and measuring temperature according to the resistance change of the temperature-sensitive conductive material. The feedback module comprises an electrical stimulation feedback array, an electromagnetic force feedback driver and a temperature feedback driver, the electrical stimulation feedback array and the electromagnetic force feedback driver are used for simulating mechanical perception, and the temperature feedback driver is used for simulating cold and warm perception. The problems that an existing tactile feedback glove is low in gesture detection recognition rate, single in feedback mode and low in tactile representation fidelity are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of human-computer interaction, and more particularly to a tactile feedback glove integrating posture detection and sensing. Background Art

[0002] Virtual reality (VR) technology can enhance the bridge between real space and cyberspace by stimulating the user's various senses - the 3D virtual world network, thus giving users an immersive experience of interacting with reality. Today, VR technology has been widely used in training, rehabilitation, education, games and other fields. Head-mounted display (HMD) systems account for the vast majority of VR systems currently developed. However, in addition to visual stimulation, comprehensive perception and feedback are also required to obtain a highly immersive VR experience.

[0003] Since the sensory nerves and motor nerves of the hands are more complex than other parts of the body, complex interactions can be achieved in VR systems, so data gloves that can provide posture detection already exist. Traditional data gloves that achieve posture detection are based on cameras or rigid sensors, which have occlusion problems, are difficult to adapt to complex hand movements, and have a strong foreign body sensation when worn. In addition, studies have shown that electrotactile stimulation can only activate nerves in the dermis of the fingertips, while tactile perception relies on the synergistic effect of nerves located in the dermis and subcutaneous tissue. Therefore, most data gloves based on single electrical stimulation cannot provide comprehensive perception. Data gloves based on force feedback often use hydraulic and pneumatic systems to achieve pressure perception, which have the defects of slow response speed and difficulty in generating vibration feedback.

[0004] Therefore, how to provide a tactile feedback glove that integrates posture detection and sensing to achieve high tactile fidelity is an urgent problem that technical personnel in this field need to solve. Summary of the invention

[0005] In view of this, the present invention provides a tactile feedback glove integrating posture detection and sensing, which solves the problems of low posture detection recognition rate, single feedback mode and low tactile reproduction fidelity of existing tactile feedback gloves.

[0006] In order to achieve the above object, the present invention adopts the following technical solution:

[0007] A tactile feedback glove integrating posture detection and sensing, comprising: a glove body, a posture detection module, a sensing module, a feedback module and a control module, wherein the posture detection module, the sensing module, the feedback module and the control module are all fixed on the glove body;

[0008] The posture detection module includes an optical fiber, which is used to convert the stress caused by the bending of the finger into the central wavelength drift, thereby obtaining the hand posture information;

[0009] The sensing module includes a pressure-temperature dual-mode sensor for collecting pressure and temperature data;

[0010] The feedback module includes an electrical stimulation feedback array, an electromagnetic force feedback driver and a temperature feedback driver, wherein the electrical stimulation feedback array and the electromagnetic force feedback driver are used to simulate mechanical perception, and the temperature feedback driver is used to simulate cold and warm perception;

[0011] The control module is used to collect data from the sensor module and send it to the host computer, receive virtual posture, pressure and temperature information reproduced by the host computer, and send the pressure and temperature information to the feedback module for feedback, so that the user can have virtual tactile perception.

[0012] Preferably, it further comprises a back-of-hand fixing frame, wherein the back-of-hand fixing frame is fixed in the glove body;

[0013] The glove body is also provided with an electrical connection layer and a packaging layer, wherein the packaging layer is located outside the electrical connection layer;

[0014] A fixed wrist strap is arranged at the opening of the glove body, a flexible printed circuit board is attached to the fixed wrist strap, the flexible printed circuit board is electrically connected to the electrical connection layer, and the control module is located on the flexible printed circuit board.

[0015] Preferably, the posture detection module further comprises a multi-channel fiber Bragg grating demodulator, the optical fiber is five fiber Bragg gratings, the five fiber Bragg gratings are respectively located in the five back-of-hand fixing frames, and the five fiber Bragg gratings are respectively connected to the five channels of the multi-channel fiber Bragg grating demodulator;

[0016] The fiber Bragg grating is used to convert the stress of finger bending into the center wavelength drift;

[0017] The multi-channel fiber grating demodulator is used to demodulate the spectrum information including the center wavelength drift and send it to the host computer, and the host computer performs multi-channel data processing to obtain the hand posture information.

[0018] Preferably, the control module comprises a sensor monitoring circuit, a feedback drive circuit, a communication circuit, a microcontroller and a power management circuit, and the sensor monitoring circuit, the feedback drive circuit, the communication circuit and the power management circuit are all connected to the microcontroller;

[0019] The sensing monitoring circuit is connected to the pressure-temperature dual-mode sensor, the feedback driving circuit is connected to the electrical stimulation feedback array and the temperature feedback driver respectively, and the electromagnetic force feedback driver is connected to the microcontroller.

[0020] Preferably, the sensing monitoring circuit includes an array scanning circuit, a digital capacitance conversion circuit and a resistance voltage acquisition circuit; the array scanning circuit is connected to the digital capacitance conversion circuit and the resistance voltage acquisition circuit respectively, and the array scanning circuit, the digital capacitance conversion circuit and the resistance voltage acquisition circuit are all connected to the microcontroller;

[0021] The feedback drive circuit includes a waveform generating circuit, an impedance monitoring circuit, a switch array, and a temperature control circuit; the waveform generating circuit is connected to the switch array, the switch array is connected to the impedance monitoring circuit, and the impedance monitoring circuit, the waveform generating circuit, and the switch array are all connected to the microcontroller;

[0022] The temperature control circuit includes an H-bridge circuit, and the H-bridge circuit is connected to the microcontroller.

[0023] Preferably, the pressure-temperature dual-mode sensor is arranged at the fingertips and the center of the phalanges of the fingers;

[0024] The pressure-temperature dual-mode sensor includes, from bottom to top, a bottom packaging layer, a lower plate electrode layer, an intermediate dielectric layer, an upper plate electrode layer and a top packaging layer. The edges of the lower plate electrode layer and the upper plate electrode layer are provided with pins, and the pins are connected to the array scanning circuit through the electrical connection layer.

[0025] Preferably, the electrical stimulation feedback array is arranged on the inner wall of the finger sleeve of the glove body;

[0026] The electrical stimulation feedback array comprises a flexible substrate, an electrical connection network and a hemispherical metal electrode, wherein the hemispherical metal electrode is electrically connected to the electrical connection network, and both the electrical connection network and the hemispherical metal electrode are located on the flexible substrate;

[0027] The electrical connection network is connected to the switch array through the electrical connection layer.

[0028] Preferably, the electromagnetic force feedback driver is arranged on the back of the hand on the outer surface of the finger sleeve of the glove body and corresponds to the nerves in the subcutaneous tissue;

[0029] The electromagnetic force feedback driver includes a Z-axis linear pulse vibration motor and a vibration motor driving circuit. The Z-axis linear pulse vibration motor is connected to the vibration motor driving circuit, and the vibration motor driving circuit is connected to the microprocessor.

[0030] Preferably, the temperature feedback driver is arranged on the palm surface of the glove body;

[0031] The temperature feedback driver comprises, from bottom to top, a bottom heat dissipation layer, a bottom flexible connection layer, a TED array, a top flexible connection layer and a top heat dissipation layer;

[0032] The bottom flexible connection layer and the top flexible connection layer are both connected to the H-bridge circuit.

[0033] Preferably, the TED array comprises P-type bismuth telluride and N-type bismuth telluride;

[0034] The bottom flexible connection layer and the top flexible connection layer both include a polyimide PI film and a patterned copper film, and the patterned copper film is located on the polyimide PI film.

[0035] It can be seen from the above technical solutions that, compared with the prior art, the present invention discloses a tactile feedback glove that integrates posture detection and sensing. The present invention solves the problems of low posture detection recognition rate, single feedback mode and low tactile reproduction fidelity of existing tactile feedback gloves by simulating pressure, vibration and temperature perception. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0037] Figure 1 This is a schematic diagram of the structure of a tactile feedback glove integrating posture detection and sensing according to an embodiment of the present invention;

[0038] Figure 2 It is a schematic diagram of the structure of the glove body;

[0039] Figure 3 This is a connection diagram of the posture detection device;

[0040] Figure 4 It is a schematic diagram of the structure of the pressure-temperature dual-mode sensor;

[0041] Figure 5 It is a schematic diagram of the structure of the electrical stimulation feedback array;

[0042] Figure 6 A flow chart for the fabrication of an electrical stimulation feedback array;

[0043] Figure 7 This is the working principle diagram of the temperature feedback driver;

[0044] Figure 8 It is the structural diagram of the temperature feedback driver;

[0045] Fig. 9 It is the system block diagram of the control module;

[0046] Among them, 1. Glove body; 11. Finger sleeve; 12. Back of hand fixed skeleton; 13. Fixed connector; 14. Palm; 141. Electrical connection layer; 142. Packaging layer; 21. Optical fiber; 22. Multi-channel fiber grating demodulator; 3. Pressure and temperature dual-mode sensor; 31. Bottom packaging layer; 32. Lower plate electrode layer; 33. Intermediate dielectric layer; 34. Upper plate electrode layer; 35. Top packaging layer; 36. Pins; 4. Electrical stimulation feedback Array; 41. Flexible substrate; 42. Electrical connection network; 43. Hemispherical metal electrode; 5. Z-axis linear pulse vibration motor; 6. Temperature feedback driver; 61. Bottom heat dissipation layer; 62. Bottom flexible connection layer; 621. Polyimide PI film; 622. Copper film; 63. P-type bismuth telluride; 64. N-type bismuth telluride; 65. Top flexible connection layer; 66. Top heat dissipation layer; 7. Wristband; 8. Flexible flat cable FFC; 9. Host computer. DETAILED DESCRIPTION

[0047] 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.

[0048] The embodiment of the present invention discloses a tactile feedback glove integrating posture detection and sensing. Figure 1 and Figure 2 As shown, it includes: a glove body 1, a posture detection module, a sensor module, a feedback module and a control module, and the posture detection module, the sensor module, the feedback module and the control module are all fixed on the glove body 1;

[0049] The posture detection module includes an optical fiber 21, which is used to convert the stress caused by the bending of the finger into the central wavelength drift, thereby obtaining the hand posture information;

[0050] The sensing module includes a pressure-temperature dual-mode sensor 3 for collecting pressure and temperature data;

[0051] The feedback module includes an electric stimulation feedback array 4, an electromagnetic force feedback driver and a temperature feedback driver 6. The electric stimulation feedback array 4 and the electromagnetic force feedback driver are used to simulate mechanical perception, and the temperature feedback driver 6 is used to simulate cold and warm perception. Mechanical perception can be divided into force perception and vibration perception. The electric stimulation feedback array 4 and the electromagnetic force feedback driver can both simulate, but the simulated frequency bands are different.

[0052] The control module is used to collect data from the sensor module and send it to the host computer, receive the virtual posture, pressure and temperature information reproduced by the host computer and send the pressure and temperature information to the feedback module for feedback, so that the user can have virtual tactile perception.

[0053] Specifically, the glove body 1 includes four parts, namely, a finger sleeve 11, a back of hand fixing frame 12, a fixing connector 13, and a palm 14, all of which are made of flexible insulating material; one end of the back of hand fixing frame 12 is connected to the opening of the finger sleeve 11, and the other end is fixed to the edge of the wristband; each back of hand fixing frame 12 is provided with a flexible fixing connector 13 for connection and fixation; the fixing connector 13 is located at the proximal interphalangeal joint of the finger, and the index finger, middle finger, and ring finger are also provided with a fixing connector 13 located at the metacarpophalangeal joint; both sides of all the fixing connectors 13 are connected to the palm 14 part, and the finger opening downwards belongs to the palm.

[0054] In order to integrate the sensor module and the feedback module on the glove body 1, an electrical connection needs to be set up. Therefore, an electrical connection layer 141 printed on a flexible substrate by dispensing silver ink is pasted on the front and back sides of the palm 14, and a flexible insulating packaging layer 142 is set thereon, which can specifically be silicone to prevent the user's hands from sweating and conducting electricity or contaminating the silver ink. Only the silver ink wires in specific parts are exposed for connection.

[0055] A wristband 7 is provided at the opening of the glove body, and a flexible printed circuit board is attached to the wristband 7. The fixed wristband is used to fix the glove on the wrist of the user.

[0056] Since the glove body 1 is made of flexible material, the tactile feedback gloves disclosed in the present invention have the advantages of being comfortable to wear, having a high degree of fit, and having a low foreign body sensation.

[0057] like Fig. 9 As shown, the control module includes a sensor monitoring circuit, a feedback drive circuit, a communication circuit, a microcontroller and a power management circuit. The sensor monitoring circuit, the feedback drive circuit, the communication circuit and the power management circuit are all connected to the microcontroller, and the communication circuit communicates with the host computer 9;

[0058] The sensing monitoring circuit is connected to the pressure-temperature dual-mode sensor, the feedback driving circuit is connected to the electric stimulation feedback array and the temperature feedback driver respectively, and the electromagnetic force feedback driver is connected to the microcontroller.

[0059] Preferably, the sensing monitoring circuit includes an array scanning circuit, a digital capacitance conversion circuit and a resistance voltage acquisition circuit; the array scanning circuit is connected to the digital capacitance conversion circuit and the resistance voltage acquisition circuit respectively, and the array scanning circuit, the digital capacitance conversion circuit and the resistance voltage acquisition circuit are all connected to a microcontroller;

[0060] The feedback drive circuit includes a waveform generating circuit, an impedance monitoring circuit, a switch array, and a temperature control circuit; the waveform generating circuit is connected to the switch array, the switch array is connected to the impedance monitoring circuit, and the impedance monitoring circuit, the waveform generating circuit, and the switch array are all connected to a microcontroller;

[0061] The temperature control circuit includes an H-bridge circuit, and the H-bridge circuit is connected to the microcontroller;

[0062] The communication circuit is composed of low-power Bluetooth and its peripheral circuits; the power management circuit is composed of a power supply, a power management chip and its peripheral circuits, which can provide different output voltages for the system.

[0063] The above control modules are integrated on a flexible printed circuit board and bonded with a film of flexible insulating and heat-dissipating material, which is bent to form a wristband, making it convenient for users to wear tactile feedback gloves and improving wearing comfort.

[0064] like Figure 3 As shown, the posture detection module also includes a multi-channel fiber Bragg grating demodulator 22, the optical fiber is specifically a fiber Bragg grating FBG, five fiber Bragg gratings are respectively connected to the five channels of the multi-channel fiber Bragg grating demodulator 22, and the multi-channel fiber Bragg grating demodulator 22 is connected to the host computer 9. The detection principle is based on the fact that the fiber Bragg grating FBG is subjected to stress and axial stretching due to finger bending, resulting in a central wavelength drift, and the drift amount is highly linearly correlated with the axial stretching amount; after the multi-channel fiber Bragg grating demodulator 22 demodulates the spectral information in the fiber Bragg grating FBG 21, it transmits the data packet to the host computer 9 through the UDP protocol, and the host computer 9 processes the multi-channel data to obtain relevant information of the hand posture.

[0065] Furthermore, the grating area of ​​the fiber Bragg grating FBG is located at the distal joint DIP, interphalangeal joint PIP and metacarpophalangeal joint MCP of the finger, and is fixed using a back-of-hand fixing frame 12 to prevent detection errors caused by sliding of the fiber Bragg grating FBG during hand movement; in addition, in order to improve the flexibility and anti-interference ability of the fiber Bragg grating FBG, polydimethylsiloxane PDMS packaging and a soft silicone tube are used as a protective cover.

[0066] In a specific embodiment, the packaging process of the fiber Bragg grating FBG is as follows: first, the PDMS prepolymer and curing agent are evenly mixed in proportion and vacuumed; then, the PDMS solution is injected into the soft silicone tube using a clean needle; then, the fiber Bragg grating FBG array is inserted; and finally, it is placed on a heating table for heating and curing.

[0067] like Figure 4As shown, the pressure-temperature dual-modal sensor 3 is distributed on the fingertips and the center of the phalanges of each finger on the palm surface of the palm 14, ensuring that the user can collect comprehensive pressure and temperature data when wearing the tactile feedback gloves; the pressure-temperature dual-modal sensor 3 includes a bottom packaging layer 31, a lower plate electrode layer 32, an intermediate dielectric layer 33, an upper plate electrode layer 34 and a top packaging layer 35 from bottom to top; in order to facilitate connection with the electrical connection layer 141, non-overlapping pins 36 are provided at the edges of the lower plate electrode layer 32 and the upper plate electrode layer 34, and the pins 36 are connected to the array scanning circuit through the electrical connection layer 141.

[0068] Furthermore, the principle of collecting pressure information by the pressure-temperature dual-mode sensor 3 is based on a parallel plate capacitor. Ignoring the edge effect of the parallel plate capacitor, the initial value C0 of its capacitance can be expressed as follows:

[0069]

[0070] Among them, ε0, ε r , A and d0 represent the vacuum dielectric constant, the relative dielectric constant of the dielectric layer, the area of ​​the two plates facing each other and the distance between the two plates respectively; when the distance between the two parallel plates decreases due to pressure, the external pressure F can be used to characterize the change in the capacitance value C:

[0071]

[0072] From this formula, it can be known that the pressure sensor based on the principle of parallel plate capacitor can measure the external pressure by detecting the change of capacitance value; where E is the Young's modulus of the dielectric layer material.

[0073] In a specific embodiment, a functional polymer material Ecoflex doped with multi-walled carbon nanotubes MWCNTs is used as the material for preparing the intermediate dielectric layer 33 of the pressure-temperature dual-mode sensor 3. When the pressure-temperature dual-mode sensor 3 is subjected to external pressure, the MWCNTs in Ecoflex are squeezed and the distance between them becomes closer, thereby causing ε r It becomes larger. According to the following sensitivity formula, the selection of Ecoflex / MWCNTs is beneficial to improving the sensitivity of the sensor.

[0074]

[0075] Furthermore, the principle of temperature sensing of the pressure-temperature dual-modal sensor 3 is to use a temperature-sensitive conductive composite material of polydimethylsiloxane PDMS / carbon black CB as the material of its upper plate electrode layer 35 and lower plate electrode layer 31. When heated, the volume of the composite material expands, and the spacing between CB in PDMS becomes larger, thereby causing the resistance to increase, and temperature detection is achieved by measuring the resistance change; the material of the bottom packaging layer 31 and the top packaging layer 35 is polydimethylsiloxane PDMS. In addition, there is no crosstalk in the measurement of pressure and temperature signals.

[0076] In a specific embodiment, the basic process for preparing the pressure-temperature dual-modal sensor 3 is as follows: first, PDMS is coated on a polyvinyl chloride plastic PVC film and spin-coated to make it uniform, and then demolded after heating and curing to form a PDMS film as the bottom encapsulation layer 31; then, the PDMS / CB homemade ink is injected into the needle of a microelectronic printer, and the PDMS film is scraped and cured to form a lower plate electrode layer 32 and a pin 36; the following printing process is similar, and after layer-by-layer scraping and curing, an intermediate dielectric layer 33 and an upper plate electrode layer 34 are obtained; finally, when preparing the top encapsulation layer 35, the PDMS film area should be larger and the thickness should be thicker to cover the entire multi-layer structure.

[0077] In a specific embodiment, PDMS / CB and Ecoflex / MWCNTs materials are both homemade inks, and the specific operation process is as follows: for PDMS / CB ink, CB is first ground into nano-scale particles using a ball mill, and then mixed with toluene and subjected to ultrasonic treatment. After treatment, PDMS prepolymer and curing agent are poured into the mixture of the two in proportion and stirred. In order to prevent bubbles from being generated during the printing process, vacuum extraction is finally performed; for Ecoflex / MWCNTs, MWCNTs are first dispersed in isopropanol and subjected to ultrasonic treatment, and then Ecoflex prepolymer and curing agent are added to the mixture of MWCNTs and isopropanol in a certain proportion, and then stirred, and vacuum extraction is also performed.

[0078] Furthermore, a plurality of pressure-temperature dual-modal sensors 3 made of homemade ink through the above process are distributed at the fingertips and central positions of the phalanges of the palm 14 to form a 2×5 sensor array, and the pins 36 of the upper plate electrode layer 34 in the same row are connected through the electrical connection layer 141, and the pins 36 of the lower plate electrode layer 32 in the same column are connected through the electrical connection layer 141; this structure uses 7 leads to introduce 10 capacitor units, which provides convenience for subsequent expansion.

[0079] Furthermore, the array scanning circuit is based on two four-to-one analog switch chips, which are responsible for selecting the columns and rows of the 2×5 sensor array respectively. The selected upper plate electrode layer 34 and the lower plate electrode layer 32 need to be grounded and discharged before detection, and the rest need to remain grounded to reduce the impact of capacitive coupling and crosstalk on the measurement results.

[0080] Furthermore, when the analog switch chip completes scanning the rows and columns of the 2×5 sensor array, the capacitance values ​​read will be connected to the digital capacitance conversion circuit in sequence. The digital capacitance conversion circuit is composed of a capacitance-to-digital conversion chip and its peripheral circuits. The capacitance-to-digital conversion chip can convert the measured capacitance value into a digital quantity and process the digital quantity through its own DSP unit, and send it to the microcontroller through the SPI interface.

[0081] like Figure 5 As shown, the electrical stimulation feedback array 4 is composed of a flexible substrate 41, an electrical connection network 42 and a hemispherical metal electrode 43; its manufacturing process is as follows Figure 6 As shown, firstly, the electrical connection network 42 made of silver paste is printed on the flexible substrate 41 using a dispensing process, and then the hemispherical metal electrodes 43 are bonded to the electrical connection network 42 in a 4×4 array form using a conductive adhesive, and finally the entire electrical stimulation feedback array 4 is bonded to the inner wall of the finger sleeve 11, and the electrical connection network 42 is connected to the switch array through the electrical connection layer 141 and FFC 8. The diameter of the hemispherical metal electrode 43 is 2 mm, and the distance between the centers of two adjacent hemispherical metal electrodes 43 is 4 mm; more specifically, the hemispherical metal electrode 43 is a 4×4 hemispherical electrode array, and the 4×4 hemispherical electrode array is bonded to the flexible substrate 41, and the flexible substrate 41 is bonded to the inner wall of the finger sleeve.

[0082] Furthermore, since the biphasic rectangular wave has the advantages of simple generation, balanced positive and negative charges, and not easy to accumulate in human tissue and cause damage compared to other electrical stimulation waveforms, a sine wave cluster with a square wave envelope is used as the electrical stimulation waveform, and the waveform generating circuit generates a biphasic square wave voltage signal to select part or all of the electrodes in the 4×4 hemispherical electrode array through the switch array, and the power supply voltage amplitude of the selected electrode is equal to that of the surrounding electrodes, but the polarity is opposite; and the waveform generating circuit can adjust the amplitude, frequency, duty cycle and other parameters of the generated voltage signal to achieve different tactile perceptions; in addition, the use of voltage output to act on the electrical stimulation feedback array 4 can ensure the timeliness of electrical stimulation; but at the same time, there is a problem of unstable stimulation effect caused by changes in the contact impedance between the human skin and the electrical stimulation array 4, which is caused by sweating or changes in the contact area of ​​the human skin; in order to ensure the consistency of the current acting on the surface of the user's fingertips, an impedance monitoring circuit is provided between the waveform generating circuit and the switch array to measure the changes in the contact impedance between the 4×4 hemispherical electrode array and the human skin and adjust the stimulation voltage in real time.

[0083] In a specific embodiment, a microcontroller controls a waveform generating circuit to generate a sine wave cluster with a square wave envelope, and the waveform generating circuit includes a DDS chip and a differential waveform amplification circuit; four four-channel DDS chips are used to control the generation of a pulse waveform, and the pulse waveform is amplified to about 40 times the original through a differential waveform amplification circuit composed of four operational amplifiers; in addition, by adjusting the timer inside the microcontroller and changing the high level time and low level time of the pulse waveform, the duty cycle, amplitude, carrier frequency, modulation wave frequency and other parameters of the electrical stimulation waveform can be adjusted.

[0084] In a specific embodiment, the impedance monitoring circuit is composed of an impedance conversion chip and its external amplification circuit. The impedance conversion chip integrates an on-chip DSP and can directly return the real and imaginary parts of the measured contact impedance to the microcontroller through the IIC interface. In order to cover the variation range of the contact impedance, an external amplification circuit is added to solve the limitation that the impedance conversion chip cannot provide the corresponding output current when the contact impedance becomes smaller.

[0085] In a specific embodiment, the impedance conversion chip measures the contact impedance at regular intervals. When the impedance conversion chip detects a change in the contact impedance, the microcontroller controls the DDS chip to adjust the amplitude of the electrical stimulation waveform so that the stimulation current remains unchanged when the contact impedance changes.

[0086] In a specific embodiment, the switch array is composed of multiple different types of four-to-one selection switch chips and their peripheral circuits, which are used to control the switching between the electrical stimulation feedback array 4 and the waveform generating circuit or the impedance monitoring circuit, and select some electrodes to perform the electrical stimulation feedback function.

[0087] In a specific embodiment, a four-way single-pole single-throw switch chip is selected to realize the application of electrical stimulation waveforms to specific electrodes, and the input end of each single-pole single-throw switch is connected to the output signal of the waveform generating circuit, and the output end is connected to the anode of the electrical stimulation feedback array 4; the four digital logic control pins of the four-way single-pole single-throw switch chip are respectively connected to the four GPIO pins of the microcontroller, and these four pins independently control the corresponding single-pole single-throw switches without affecting each other, thereby realizing the independent application of electrical stimulation waveforms.

[0088] In a specific embodiment, a multiplexer with four differential channels is selected to realize the measurement of contact impedance, one end of the four differential inputs is connected to the anode of the electrical stimulation feedback array 4, the other end is connected to the cathode of the electrical stimulation feedback array 4, and the common differential output is connected to the impedance conversion chip; the address selection end of the multiplexer switch is connected to the GPIO pin of the microcontroller, and the microcontroller outputs four combinations of high and low levels to control the selection of one of the differential inputs; thereby, the impedance measurement signal generated by the impedance monitoring circuit acts on the corresponding anode of the electrical stimulation feedback array 4, and flows through the cathode of the electrical stimulation feedback array 4 to return the output result of the impedance measurement signal; by setting 4 identical multiplexers, the impedance measurement of different parts of the finger skin attached to the 4×4 hemispherical electrode array can be realized.

[0089] Furthermore, in order to ensure that the electrical stimulation waveform output by the waveform generating circuit and the impedance measurement signal generated by the impedance monitoring circuit do not interfere with each other, it is necessary to disconnect the impedance measurement signal when applying the stimulation voltage and disconnect the electrical stimulation waveform when measuring the contact impedance; in addition, in order to accurately measure the contact impedance, the connection between the cathode of the electrical stimulation feedback array 4 and the analog ground should be disconnected during the process.

[0090] In a specific embodiment, a four-way single-pole single-throw switch chip is used to achieve switching between applying electrical stimulation voltage and measuring contact impedance. The input end of each single-pole single-throw switch is connected to the cathode of the electrical stimulation feedback array 4, and the output end is connected to the analog ground; the four digital logic control pins of the four-way single-pole single-throw switch chip are respectively connected to the four GPIO pins of the microcontroller, and each single-pole single-throw switch is independently controlled by controlling the four GPIO outputs to a high level; when the stimulation voltage is applied, the single-pole single-throw switch is in a closed state, and the cathode of the electrical stimulation feedback array 4 is connected to the analog ground to form a complete closed path, thereby generating electrical stimulation feedback; when measuring contact impedance, the single-pole single-throw switch is in an open state, ensuring that the impedance measurement signal only flows through the skin and the hemispherical electrode.

[0091] In order to provide comprehensive tactile perception, the electromagnetic force feedback driver 5 uses electromagnetic force feedback to activate the nerves located in the subcutaneous tissue. The electromagnetic force feedback driver 5 is composed of a Z-axis linear pulse vibration motor and a vibration motor driving circuit. The Z-axis linear pulse vibration motor is connected to the vibration motor circuit, and the vibration motor driving circuit is connected to the IIC interface of the microcontroller. The vibration motor driving chip can achieve vibration effects of different frequencies, times and intensities. The Z-axis linear pulse vibration motor is a cylindrical shape with a bottom diameter of 8mm and a height of 2.7mm.

[0092] like Figure 8 As shown, the temperature feedback driver 6 is distributed on the palm surface of the palm 14, including a bottom heat dissipation layer 61, a bottom flexible connection layer 62, a TED array composed of P-type bismuth telluride 63 and N-type bismuth telluride 64, a top flexible connection layer 65 and a top heat dissipation layer 66; the bottom flexible connection layer 62 uses a composite material composed of a polyimide PI film 621 and a patterned copper film 622 as a substrate, and the top flexible connection layer 65 uses the same material, but the patterning method of the copper film is different; in order to minimize the adverse heat transfer loss between the two surfaces, insulating ceramic microfibers are filled in the gaps of the TED array to prevent heat transfer from the bottom to the top.

[0093] The temperature feedback driver 6 is based on the Seebeck effect and its working principle is as follows Figure 7 As shown, when P-type bismuth telluride 63 and N-type bismuth telluride 64 are combined into a pair of thermocouples, the upper surface and the lower surface of the thermocouple are connected by conductive connecting plates, and the two ends of the conductive connecting plate on the lower surface are connected to the positive and negative poles of the power supply by wires to form a closed loop, the connection between the two conductive connecting plates will absorb or release heat; the absorption or release of heat is related to the direction of the current. When the current flows from N-type bismuth telluride 64 to P-type bismuth telluride 63, the connection absorbs heat and the temperature drops. When the current flows from P-type bismuth telluride 63 to N-type bismuth telluride 64, the connection releases heat and the temperature rises. Therefore, the perception of cold and heat can be simulated by switching the direction of current flow.

[0094] In a specific embodiment, the basic process of preparing the temperature feedback driver 6 is as follows: first, the copper film 622 on the polyimide PI film 621 is patterned; then, solder paste is printed on the patterned copper film, and P-type bismuth telluride 63 and N-type bismuth telluride 64 are placed on the solder paste in a PNP form, and bonded using a welding machine; after bonding, the gaps between the TED arrays are filled with insulating ceramic microfibers; then, the TED array is connected with a top flexible connection layer 65 that has been patterned in the same manner; finally, a top heat dissipation layer 66 and a bottom heat dissipation layer 61 are correspondingly bonded to the top and bottom of the multi-layer structure.

[0095] In a specific embodiment, the bottom flexible connection layer 62 and the top flexible connection layer 65 of the temperature feedback driver 6 are connected to the temperature control circuit through the flexible flat cable FFC 8. The temperature control circuit is composed of an H-bridge chip and its peripheral circuits. The H-bridge chip is connected to the PWM output pin of the microcontroller. The heat flux is controlled by controlling PWM, and the current direction can be changed to achieve switching between heating and cooling modes.

[0096] The working principle of the present invention is:

[0097] When the user uses the tactile feedback gloves to make gestures, the microcontroller processes the electrical signals collected by the pressure and temperature dual-modal sensors and sends them to the host computer via the communication circuit. The host computer comprehensively processes the electrical signals processed by the microcontroller and the spectral signals collected by the multi-channel fiber grating demodulator to reproduce the posture, pressure and temperature information of the virtual hand; the reproduced information is then sent to the microcontroller via the communication circuit, and the microcontroller controls the feedback module to execute feedback, allowing the user to have virtual tactile perception.

[0098] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0099] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A tactile feedback glove integrating posture detection and sensing, characterized in that: include: A glove body, a posture detection module, a sensor module, a feedback module and a control module, wherein the posture detection module, the sensor module, the feedback module and the control module are all fixed on the glove body; The posture detection module includes an optical fiber, which is used to convert the stress caused by the bending of the finger into the central wavelength drift, thereby obtaining the hand posture information; The sensing module includes a pressure-temperature dual-mode sensor for collecting pressure and temperature data; The feedback module includes an electrical stimulation feedback array, an electromagnetic force feedback driver and a temperature feedback driver, wherein the electrical stimulation feedback array and the electromagnetic force feedback driver are used to simulate mechanical perception, and the temperature feedback driver is used to simulate cold and warm perception; The control module is used to collect data from the sensor module and send it to the host computer, receive virtual posture, pressure and temperature information reproduced by the host computer, and send the pressure and temperature information to the feedback module for feedback, so that the user can have virtual tactile perception.

2. The tactile feedback glove integrating posture detection and sensing according to claim 1, characterized in that: It also includes a back-of-hand fixing frame, wherein the back-of-hand fixing frame is fixed in the glove body; The glove body is also provided with an electrical connection layer and a packaging layer, wherein the packaging layer is located outside the electrical connection layer; A fixed wrist strap is arranged at the opening of the glove body, a flexible printed circuit board is attached to the fixed wrist strap, the flexible printed circuit board is electrically connected to the electrical connection layer, and the control module is located on the flexible printed circuit board.

3. The tactile feedback glove integrating posture detection and sensing according to claim 2, characterized in that: The posture detection module also includes a multi-channel fiber Bragg grating demodulator, the optical fiber is five fiber Bragg gratings, the five fiber Bragg gratings are respectively located in the five back-of-hand fixing frames, and the five fiber Bragg gratings are respectively connected to the five channels of the multi-channel fiber Bragg grating demodulator; The fiber Bragg grating is used to convert the stress of finger bending into the center wavelength drift; The multi-channel fiber grating demodulator is used to demodulate the spectrum information including the center wavelength drift and send it to the host computer, and the host computer performs multi-channel data processing to obtain the hand posture information.

4. The tactile feedback glove integrating posture detection and sensing according to claim 2, characterized in that: The control module includes a sensor monitoring circuit, a feedback drive circuit, a communication circuit, a microcontroller and a power management circuit, and the sensor monitoring circuit, the feedback drive circuit, the communication circuit and the power management circuit are all connected to the microcontroller; The sensing monitoring circuit is connected to the pressure-temperature dual-mode sensor, the feedback driving circuit is connected to the electrical stimulation feedback array and the temperature feedback driver respectively, and the electromagnetic force feedback driver is connected to the microcontroller.

5. The tactile feedback glove integrating posture detection and sensing according to claim 4, characterized in that: The sensor monitoring circuit includes an array scanning circuit, a digital capacitance conversion circuit and a resistance voltage acquisition circuit; the array scanning circuit is connected to the digital capacitance conversion circuit and the resistance voltage acquisition circuit respectively, and the array scanning circuit, the digital capacitance conversion circuit and the resistance voltage acquisition circuit are all connected to the microcontroller; The feedback drive circuit includes a waveform generating circuit, an impedance monitoring circuit, a switch array, and a temperature control circuit; The waveform generating circuit is connected to the switch array, the switch array is connected to the impedance monitoring circuit, and the impedance monitoring circuit, the waveform generating circuit and the switch array are all connected to the microcontroller; The temperature control circuit includes an H-bridge circuit, and the H-bridge circuit is connected to the microcontroller.

6. The tactile feedback glove integrating posture detection and sensing according to claim 5, characterized in that: The pressure-temperature dual-mode sensor is arranged at the fingertips and the center of the phalanges of the fingers; The pressure-temperature dual-mode sensor includes, from bottom to top, a bottom packaging layer, a lower plate electrode layer, an intermediate dielectric layer, an upper plate electrode layer and a top packaging layer. The edges of the lower plate electrode layer and the upper plate electrode layer are provided with pins, and the pins are connected to the array scanning circuit through the electrical connection layer.

7. The tactile feedback glove integrating posture detection and sensing according to claim 5, characterized in that: The electrical stimulation feedback array is arranged on the inner wall of the finger sleeve of the glove body; The electrical stimulation feedback array comprises a flexible substrate, an electrical connection network and a hemispherical metal electrode, wherein the hemispherical metal electrode is electrically connected to the electrical connection network, and both the electrical connection network and the hemispherical metal electrode are located on the flexible substrate; The electrical connection network is connected to the switch array through the electrical connection layer.

8. The tactile feedback glove integrating posture detection and sensing according to claim 5, characterized in that: The electromagnetic force feedback driver is arranged on the outer surface of the finger sleeve of the glove body and corresponds to the nerves in the subcutaneous tissue; The electromagnetic force feedback driver includes a Z-axis linear pulse vibration motor and a vibration motor driving circuit. The Z-axis linear pulse vibration motor is connected to the vibration motor driving circuit, and the vibration motor driving circuit is connected to the microprocessor.

9. The tactile feedback glove integrating posture detection and sensing according to claim 5, characterized in that: The temperature feedback driver is arranged on the palm surface of the glove body; The temperature feedback driver comprises, from bottom to top, a bottom heat dissipation layer, a bottom flexible connection layer, a TED array, a top flexible connection layer and a top heat dissipation layer; The bottom flexible connection layer and the top flexible connection layer are both connected to the H-bridge circuit.

10. The tactile feedback glove integrating posture detection and sensing according to claim 9, characterized in that: The TED array includes P-type bismuth telluride and N-type bismuth telluride; The bottom flexible connection layer and the top flexible connection layer both include a polyimide PI film and a patterned copper film, and the patterned copper film is located on the polyimide PI film.

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