Haptic glove device and rendering method based on vibration and skin displacement control

Abstract

The present application relates to a kind of based on vibration and skin displacement control's haptic glove device and rendering method, belong to virtual reality and man-machine interaction field.The mapping model between the shape features such as the distance between fingertip and object surface, object stiffness coefficient and surface curvature and each parameter of haptic drive signal is established to realize the haptic reproduction of three-dimensional object profile, elasticity, surface texture, impact and fluid flow in virtual space, and the haptic glove device includes audiovisual presentation unit, computing unit, posture sensing unit, haptic interaction unit, instruction control unit and signal driving unit.The present application has the advantages that: the haptic feedback device can realize the haptic reproduction of the features such as convex, concave, edge, soft and hard degree and surface texture of three-dimensional object in virtual space, impact force, fluid flow and other tactile sensation without exerting strong dynamic force, enriches tactile experience, and enhances the real feeling and immersion when interacting with virtual object.

Description

Technical Field

[0001] This invention belongs to the field of virtual reality and human-computer interaction, and particularly relates to a tactile glove device and rendering method based on vibration and skin displacement control. Background Technology

[0002] Touch, as an important sensory channel for the human body, is responsible for transmitting tactile information such as shape, volume, contour, material, texture, temperature, and humidity from the outside world. Currently available virtual reality equipment often provides users with high-definition visual and surround sound presentations, but it cannot provide a believable and realistic tactile experience. With the rapid development of virtual reality display technology and the widespread adoption of AR and VR devices, more and more people are choosing to engage in entertainment, socializing, shopping, and working in virtual spaces. This has led to a growing demand for tactile feedback. Therefore, reproducing tactile feedback when interacting with objects in virtual spaces is a problem that urgently needs to be solved.

[0003] Currently, wearable devices used in AR and VR that provide tactile feedback to the human body are mostly researched in the form of gloves, belts, vests, wristbands, and shoes. Among them, glove-type wearable devices generally use motors to generate kinematic force to move the entire finger, producing tactile sensations such as grasping and external force. In terms of skin tactile reproduction, most only use vibrators to provide single vibration feedback cues to the fingertips. There is little research on how to realistically present the contours, hardness, and surface texture of objects in the virtual world. Tactile feedback devices neglect tactile stimulation methods such as generating normal pressure at the fingertips, multi-directional skin displacement, and changes in skin contact area. Therefore, it is essential to develop glove-type tactile feedback devices and rendering methods that use the above-mentioned tactile stimulation methods to present the tactile sensations of the contours, hardness, and surface texture of three-dimensional objects in virtual space.

[0004] There are already some glove-style haptic feedback devices and rendering methods.

[0005] Chinese patent CN104898842A, entitled "Wearable finger-type force-haptic interaction device and implementation method for mobile terminals", discloses a wearable finger-type force-haptic interaction device and implementation method applied to the screen surface of a mobile terminal. It presents tactile sensations such as roughness, shape, and hardness on the image by vibrating a 3-row, 3-column piezoelectric ceramic vibrator array at the fingertip position. However, its tactile stimulation method is relatively simple, the sense of realism is weak, it does not consider the influence of hand posture on the interaction effect, and it can only be applied to mobile terminals.

[0006] Chinese patent CN109375772A, entitled "A Multi-Functional Haptic Feedback Glove," discloses a multi-functional haptic feedback glove applicable to virtual reality. This device can measure the position and posture of fingers in space, generate kinematic force feedback at the finger joints by changing the device's stiffness, generate fingertip pressure through soft actuators, and generate temperature or texture tactile sensations through haptic feedback units. While this device can simply reproduce the force sensation of a human hand grasping and pinching, it does not consider the elasticity and edge contours of virtual objects, neglects texture tactile feature rendering methods, and provides kinematic force feedback with certain risks. Furthermore, the device occupies a large hand space and has poor wearability.

[0007] The Chinese patents published in 2021, namely "A Wearable Flexible XR Somatosensory Glove with High-Precision Force Feedback" (CN113261727A), "A Somatosensory Game Glove" (CN107413047A) published in 2017, and "A VR Somatosensory Glove with Adjustable Resistance" (CN215075756U), respectively achieve kinematic force and tactile feedback of the whole finger or finger joint through micro geared motors, pneumatic drive, and hydraulic drive, which can present a simple gripping feeling. However, the above devices have complex structures, poor wearability, and neglect the presentation of skin tactile information.

[0008] Chinese patent CN107422855A, entitled "A Corrugated Balloon-Type Tactile Glove Providing Clamping Force Sensation and Manufacturing Method Thereof," discloses a pneumatically driven wearable haptic feedback glove device. This device achieves fingertip contact sensation and pressure by inflating and deflating a balloon in the palm, but it can only provide haptic feedback during grasping actions. Chinese patent CN106527738A, entitled "A Multi-Information Somatosensory Interactive Glove System and Method for Virtual Reality Systems," discloses a glove system and haptic presentation method that achieves haptic feedback through vibration. However, its vibrator is located on the palm side near the knuckles, providing only vibrational haptic cues, resulting in a weak sense of realism in the haptic presentation. Summary of the Invention

[0009] This invention provides a tactile glove device and rendering method based on vibration and skin displacement control, in order to solve the problem that existing glove-type wearable tactile feedback devices ignore the stimulation mode of fingertip skin displacement in all directions, and lack the ability and rendering method to provide users with tactile sensations such as three-dimensional object contours, softness, surface texture, impact force, and fluid flow.

[0010] The technical solution adopted in this invention is to establish a mathematical mapping model between the interactive feature parameters of three-dimensional objects and the tactile signal parameters in virtual space. A glove-style tactile reproduction device is then used with a specific rendering method to provide users with tactile sensations such as the outline of three-dimensional objects, softness, surface texture, impact force, and fluid flow. The specific rendering method is as follows:

[0011] 1) Tactile feedback rendering method at the fingertip: use vibration stimulation to render contours and textures, use normal pressure stimulation to render elasticity, and use tangential force of fingertip skin stimulation to render friction.

[0012] 2) Haptic feedback rendering method for non-fingertip locations: Use vibrators installed on other non-fingertip locations such as the proximal knuckles of the fingers, the palm, and the back of the hand to generate haptic vibrations to render impact, virtual object outlines, and gas or liquid in a flowing state.

[0013] The haptic feedback rendering method for fingertip position according to the present invention includes the following steps:

[0014] 1) The interaction process between fingers and object surfaces in virtual space is divided into four stages: no tactile effect stage, outline stage, contact stage, and penetration warning stage.

[0015] The specific stage division method is as follows: Obtain the spatial coordinates P of the center point of the fingertip in virtual space. Construct a circle with a radius of 0.5cm along the fingertip tangent direction with point P as the center. This circle is called the fingertip circle. Obtain 12 points evenly on the fingertip circle. These points are called fingertip points, and their spatial coordinates are P. i Where i is 1 to 12; using 12 fingertips as starting points, find the minimum distance from each fingertip to the surface of the virtual space object, and the fingertip distance length is L. i Where i is from 1 to 12; the minimum value among the distances between the 12 fingertips is selected as the distance L from the fingertip to the surface of the virtual object. f When the fingertip is outside the object L f If the value is positive, L is inside the object. f It is a negative value; L f The point of intersection with the object's surface is called the surface contact point P. s ;

[0016] According to L f The value determines the current interaction stage of the finger, specifically: when L... f ∈[0.5×l1,+∞), representing the stage without tactile effect; when L f ∈[0.2×l2,0.5×l1), which is the contour stage; when L f ∈[-0.5×l³, 0.2×l²), representing the contact stage; when L f∈(-∞, -0.5×l3), which is the penetration warning stage; all length units are centimeters, and l1, l2, and l3 are non-zero coefficients;

[0017] 2) Calculate the required drive signal voltage amplitude for the vibration tactile feedback during the contouring stage based on the finger position:

[0018]

[0019] Where a s0 For the initial profile vibration acceleration, a s1 The maximum profile vibration acceleration is added, b1 is the profile vibration linearity coefficient, and g1 is the profile vibration acceleration intercept;

[0020] 3) The driving signal required for vibration tactile feedback during the contact phase:

[0021] (1) When the finger moves from the outline stage to the contact stage, the vibrator generates a tactile feedback that simulates a collision or contact sensation. The amplitude of the fingertip vibrator drive signal voltage during contact collision is:

[0022] A c =b2[a c0 ×V n +1.5(a s1 +a s0 )]+g2

[0023] Among them, a c0 V is the reference acceleration for the collision velocity. n b2 is the normal component of the fingertip velocity on the surface of the virtual object at the moment of stage change, g2 is the linear coefficient of contact collision vibration, and g2 is the intercept of contact collision vibration acceleration.

[0024] (2) When the finger approaches the outline edge of the virtual 3D object during the contact phase, the vibrator generates continuous, sharp, and pressure-like tactile feedback. The amplitude of the fingertip vibrator drive signal voltage when rendering the virtual object's outline edge is:

[0025]

[0026] Where a e0 For the initial edge vibration acceleration, a e1 To add the maximum edge vibration acceleration, b3 is the edge vibration linearity coefficient, and g3 is the edge vibration acceleration intercept;

[0027] (3) When the finger moves tangentially on the surface of the virtual 3D object during the contact phase, the vibrator generates continuous and subtle tactile feedback to render the surface texture of the object. The amplitude of the fingertip vibrator drive signal voltage during rendering the virtual object surface texture is:

[0028]

[0029] Among them, h nt1 For the old normalized grayscale, h nt2 For the new normalized grayscale, a t0 For the background noise texture vibration acceleration, a t1 Let a be the initial texture vibration acceleration. t2 To add maximum texture vibration acceleration, m t The texture vibration reference coefficient is A; the driving voltage is A. t The value is refreshed every t1 time interval, b4 is the texture vibration linear coefficient, and g4 is the texture vibration acceleration intercept.

[0030] 4) Calculate the required drive signal voltage amplitude A for the vibration tactile feedback during the penetration warning stage based on the finger position. w :

[0031] A w =b5(m w ×a w )+g5

[0032] Among them, a w For the initial penetration warning vibration acceleration, m w b5 is the penetration warning coefficient, g5 is the penetration warning vibration linearity coefficient, and g5 is the penetration warning vibration acceleration intercept.

[0033] 5) Preprocess the drive signal applied to the vibrator to overcome the problems of slow start-up and stop times, weak initial vibration, and delayed stop vibration. The specific method is as follows:

[0034] When the vibrator switches from a non-vibrating state to a vibrating state or from a low-acceleration vibration state to a high-acceleration vibration state, the voltage amplitude of the first two cycles of the newly applied vibration drive signal is increased to twice the original value; when the vibrator switches from a vibrating state to a non-vibrating state, the last applied vibration drive signal is extended for one cycle, the phase of the signal is shifted by 180°, and the voltage amplitude is reduced to half the original value.

[0035] 6) The contact phase normal pressure stimulation tactile feedback is used to render the elasticity of the object. The fingertip normal pressure F generated by the fingertip pressure actuator is used to convey the elasticity of the object. n for:

[0036] F n =(0.2l2-L) f )×k n ×F n1 +F n0

[0037] Where, k n F is the stiffness coefficient of the virtual object.n1 To add the maximum fingertip pressure coefficient, F n0 This is the initial fingertip pressure coefficient;

[0038] 7) During the contact phase, the tactile feedback stimulated by the fingertip tangential force is used to render the frictional force and its direction. The expressions for the driving voltage applied by the X-direction and Y-direction movement actuators are as follows:

[0039]

[0040] Among them, V t V represents the tangential component of the fingertip velocity on the surface of the virtual object. tx V ty F represents the tangential components of the fingertip velocity in the X and Y directions on the surface of the virtual object. t0 b6 is the maximum unidirectional tangential force on the skin, g6 is the linear coefficient of the tangential force, and g6 is the intercept of the tangential force.

[0041] The haptic feedback rendering method for non-finger-tip positions described in this invention includes the following steps:

[0042] 1) Use a vibration motor located in the center of the palm to render the impact force. The envelope is in the form of exponential decay. Only the first three cycles are output. The carrier frequency parameter F hv The relative velocity V between the palm and the object was obtained through subjective discrimination and realism experiments. c The expression for the driving signal of the palm vibrator, based on the mass M of the object, is as follows:

[0043] Where k hv This is the impact strength coefficient.

[0044] 2) An array of vibrating motors located in the palm, back of the hand, inner side of the proximal knuckles of the fingers, and outer side of the proximal knuckles of the fingers are used to render the tactile sensation of the hand contacting the outline of a virtual object. The intensity of each vibrating motor varies with the distance L between the motor and the surface of the virtual object. tv As this changes, the expression for the single vibrator drive signal is:

[0045] A tv =(k tv ×|L tv |+k tv0 )×sin(2π×F tv ×t)

[0046] Where, k tv k is the contact vibration amplification factor. tv0 This represents the initial amplitude of the contact vibration.

[0047] 3) An array of vibrating motors located in the palm, back of the hand, inner side of the proximal knuckles of the fingers, and outer side of the proximal knuckles of the fingers are used to render the tactile sensation of gas or liquid flowing through the hand. The drive signal applied to each vibrator is a single-cycle repetitive standard sine wave. The first vibrator in the direction of the virtual gas or liquid flow has a sine wave phase of 0 and generates a single cycle with a frequency of F. fv The vibration of the other vibrators is determined by their mapping distance d from the first vibrator in the flow direction. v The difference and flow velocity v f The different phases of the same-frequency single-cycle oscillations, which are delayed due to their different frequencies, affect the phase of the driving signals of each oscillator. The change is as follows: In the formula This is the fluid vibration delay coefficient.

[0048] The glove-type tactile reproduction device of the present invention includes an audiovisual presentation unit, a computing unit, a posture sensing unit, a tactile interaction unit, a command control unit, and a signal driving unit, wherein:

[0049] The posture sensing unit acquires information such as the user's hand position, posture, and fingertip pressure, and transmits it to the computing unit. The computing unit processes the sensing data and calculates and generates the user's hand model and virtual 3D object in real time in the virtual 3D space. It uses haptic rendering methods to generate drive commands for each actuator and transmits audiovisual data to the audiovisual presentation unit and drive command data to the haptic interaction unit. The audiovisual presentation unit presents the scene of the virtual 3D space to the user through video and sound, helping the user to judge the relative position of the virtual hand and the virtual 3D space based on their own proprioception and perform synchronized interactive actions. After receiving the drive command data, the command control unit controls the signal drive unit to transmit drive signals for each actuator to the haptic interaction unit, so that the haptic interaction unit can provide tactile stimulation to the user and reproduce the tactile sensation.

[0050] The tactile interaction unit described in this invention can be divided into a fingertip part and other parts, and consists of a carrier glove, a vibration tactile module, a fingertip pressure module, a fingertip three-degree-of-freedom skin displacement module, and a sensor module belonging to the posture sensing unit, in order to provide tactile stimulation to the user and generate tactile feedback.

[0051] In the aforementioned tactile interaction unit, other parts consist of vibrators embedded in the glove fabric or bonded to the glove carrier. The vibrators are located near the phalanges, fingertips, backs of the fingers, and the palm and back of the hand. The fingertip part consists of a fingertip moving platform and a finger back fixing platform. The finger back fixing platform is fixed to the back of the distal phalanx by embedding it in the glove fabric, bonding it to the glove carrier, or binding the finger with an elastic bandage. The fingertip moving platform and the finger back fixing platform are connected by a spring to prevent the weight of the moving platform from affecting the fingertip pressure and contact area after the hand posture changes. The fingertip moving platform uses soft silicone as a base, and some actuators and sensors are installed or embedded in the silicone base. The finger back fixing platform can optionally be equipped with actuators to control the movement of the moving platform.

[0052] The advantages of this invention are: the tactile feedback device can reproduce the tactile features of three-dimensional objects in virtual space, such as protrusions, depressions, edges, softness and hardness, and surface texture, as well as the tactile sensations such as impact and fluid flow, without applying strong kinematic force, thus enriching the tactile experience and enhancing the realism and immersion of interacting with virtual objects. Attached Figure Description

[0053] Figure 1 This is a schematic diagram of the structure of the present invention;

[0054] Figure 2 This is a schematic diagram of the tactile interaction unit;

[0055] Figure 3 This is a block diagram of the drive circuit;

[0056] Figure 4 This is a flowchart of the haptic reproduction rendering method;

[0057] Figure 5 This is a diagram illustrating the stages of fingertip tactile rendering.

[0058] Figure 6 It is a curve showing the fitting relationship between the driving voltage and the maximum acceleration data of the vibrator;

[0059] Figure 7 This is a schematic diagram of a method for rendering surface textures using fingertip vibration stimulation.

[0060] Figure 8 This is a schematic diagram of the preprocessing of the vibrator drive signal.

[0061] Figure 9 This is a schematic diagram of the preprocessing for stopping the vibrator drive signal;

[0062] Figure 10 A schematic diagram of the non-finger-tip tactile rendering method. Detailed Implementation

[0063] To make the objectives, features and advantages of the present invention more apparent and understandable, the following detailed description is provided with reference to the accompanying drawings and specific embodiments.

[0064] First, we introduce a tactile glove device based on vibration and skin displacement control, as shown in the schematic diagram below. Figure 1 As shown, it includes:

[0065] (1) Audiovisual presentation unit 1, including devices that can present visual and auditory information to the user, such as an integrated flat panel display, VR headset, XR glasses and matching headphones or audio system;

[0066] (2) Computing unit 2, including personal computer, laptop computer, workstation, dedicated computing device or cloud server device, etc., for sensor data processing and virtual space physical simulation calculation;

[0067] (3) Posture sensing unit 3, including IMU sensor, bending sensor, ultrasonic positioning device, infrared positioning device or visual camera to realize spatial positioning or posture sensing. The above sensors can be distributed and mounted on the fixed frame on the carrier glove, VR helmet, VR handle or arm to provide the computing unit and command control unit with the position information and posture information of the user's head and hand.

[0068] (4) The tactile interaction unit 4 consists of a carrier glove, a vibration tactile module, a fingertip pressure module, a fingertip three-degree-of-freedom skin displacement module, and a sensor module belonging to the posture sensing unit, which is used to provide tactile stimulation to the user and generate tactile feedback.

[0069] The aforementioned carrier gloves are in the form of commonly seen full-finger gloves or finger cots, made of materials such as cotton, nylon, leather, or rubber, allowing users to wear them freely. The vibration haptic module, fingertip pressure module, fingertip 2DOF skin displacement module, and sensor module are all mounted, installed, or attached to the carrier gloves.

[0070] The aforementioned vibration tactile module refers to a mechanism that generates vibrational tactile sensation in the hand using a vibrator or vibrator array. The vibrator is installed at the fingertip of each finger, or alternatively, it can be installed simultaneously at the knuckles of each finger, the palm, the back of the hand, or the wrist, among other locations on the hand. The vibrator can be a linear motor, piezoelectric ceramic disc, voice coil motor, or a vibrator based on shape memory metal or pneumatic / hydraulic principles.

[0071] The aforementioned fingertip pressure module refers to a mechanism that applies downward pressure to the fingertips, causing normal displacement of the skin and generating a pressure sensation in the hand. The actuator that provides the pressure is installed at the distal phalanx, and the actuator can be an AC motor, DC motor, servo motor, pneumatic mechanism, or voice coil motor, etc.

[0072] The aforementioned three-degree-of-freedom fingertip skin displacement module refers to a mechanism that uses an actuator to drive a moving platform, causing normal and tangential displacement of the fingertip skin. The actuator can be an AC motor, DC motor, servo motor, pneumatic mechanism, or voice coil motor, etc. The connection method for the actuator-driven moving platform can be mechanical linkage, bracket fixation, cable connection, etc. The moving platform can be made of elastic rubber or highly malleable plastic material, directly contacting the fingertip skin; the contact surface is made of rubber or adhesive materials to maximize adhesion to the skin and provide sufficient friction and skin traction; simultaneously, the moving platform serves as a carrier for other actuators such as vibrators and bending actuators.

[0073] The aforementioned sensor module is part of the attitude sensing unit, and is a mechanism installed on the carrier glove to realize functions such as hand position and attitude detection, and finger joint flexure detection. This module can optionally be equipped with IMU sensors, bending sensors, infrared or ultrasonic sensors, pressure sensors, and visual camera marker color blocks, etc.

[0074] (5) The instruction control unit 5 consists of a processor module, a signal transmission module, a sensor signal processing module and a power supply module. It is used to receive and send sensor-collected data, receive tactile instructions transmitted by the virtual space construction unit, and generate and output tactile feedback signals.

[0075] (6) Signal driving unit 6, composed of a signal preprocessing module, a voltage amplification module, a power amplification module, etc., is used to amplify the voltage and power of the tactile feedback signal, generate driving signals to drive various drivers to work and generate tactile feedback. The specific driving circuit can be a DAC analog signal generation circuit, a PWM analog signal generation circuit, etc.

[0076] The aforementioned glove-type wearable haptic feedback device comprises the following components: an audiovisual presentation unit, a computing unit, a posture sensing unit, a haptic interaction (display) unit, a command control unit, and a signal driving unit. The audiovisual presentation unit uses a commercial virtual reality headset. The posture sensing unit uses the positioning and posture sensing devices integrated into commercial virtual reality equipment. The computing unit uses a personal laptop computer equipped with the Unity 3D interactive content creation and operation platform. The command control unit and signal driving unit are directly integrated into the back of the sleeve or the glove itself. Power is supplied by a rechargeable lithium battery, and 2.4GHz wireless technology is used to transmit information with the virtual space construction unit. Drive signals are transmitted to the haptic interaction unit via flexible circuitry, and sensor data is transmitted to the posture sensing unit.

[0077] The following describes the workflow of the glove-type tactile reproduction device and the functions and connections of its various units: The posture sensing unit acquires information such as the user's hand position, posture, and fingertip pressure, and transmits it to the computing unit; the computing unit processes the sensing data and calculates and generates the user's hand model and virtual 3D object in real time in virtual 3D space, uses tactile rendering methods to generate drive commands for each actuator, and transmits audiovisual data to the audiovisual presentation unit and drive command data to the tactile interaction unit; the audiovisual presentation unit presents the scene of the virtual 3D space to the user through video and sound, helping the user to judge the relative position of the virtual hand and the virtual 3D space based on their own proprioception and perform synchronized interactive actions; after receiving the drive command data, the command control unit controls the signal drive unit to transmit the drive signals of each actuator to the tactile interaction unit, so that the tactile interaction unit can provide tactile stimulation to the user and reproduce the tactile sensation.

[0078] The specific structure of the tactile interaction unit is as follows: The tactile interaction unit is divided into a non-fingerpoint part and a fingerpoint part. The non-fingerpoint part consists of a vibrator embedded in the glove fabric or bonded to the glove carrier. The vibrator is located on the fingertips, backs of the fingers, palm, and backs of the hand near the knuckles. The fingerpoint part consists of a fingertip moving platform and a finger back fixing platform. The finger back fixing platform is fixed to the back of the distal phalanx by embedding it in the glove fabric, bonding it to the glove carrier, or binding the finger with an elastic bandage. A spring connects the fingertip moving platform and the finger back fixing platform to prevent the weight of the moving platform from affecting the fingertip pressure and contact area after changes in hand posture. The fingertip moving platform uses soft silicone as a base, with some actuators and sensors mounted or embedded in the silicone base. An actuator can be optionally mounted on the finger back fixing platform to control the movement of the moving platform.

[0079] The following describes a specific embodiment of a glove-type wearable haptic feedback device:

[0080] The auditory presentation unit uses the commercial virtual reality headset Oculus; in the posture sensing unit, the overall hand positioning and posture sensing use the positioning and posture sensing devices built into the Oculus device, while finger positioning and gesture posture use bending sensors and IMU sensors; the computing unit uses a personal laptop equipped with the Unity 3D engine; the command control unit and signal drive unit are integrated as control and drive circuits on the back of the sleeve or carrier glove, powered by a rechargeable lithium battery, and use 2.4GHz wireless technology to achieve information transmission with the computing unit, transmitting drive signals to the haptic interaction unit and transmitting sensing data to the posture sensing unit through flexible circuits.

[0081] The following describes a specific embodiment of a tactile interaction unit structure. Figure 2 This is a schematic diagram of the tactile interaction unit structure.

[0082] The tactile interaction unit structure is divided into a non-fingerpoint part and a fingerpoint part. Taking the right hand as an example, the non-fingerpoint part consists of vibrators embedded in or bonded to the glove carrier 401, providing vibration stimulation only to the non-fingerpoint area. A total of 12 linear vibrators are installed on a single glove in the non-fingerpoint area. Ten of these vibrators 402 are required to have a transverse cross-sectional area of ​​less than 1.5 square centimeters and a thickness of less than 5 millimeters to meet wearability requirements. The palm-side vibrators are installed about 1 centimeter from the extension line of each finger near the phalanx towards the palm, and the back-of-hand vibrators are installed near the center of each finger near the phalanx on the back of the hand. The other two vibrators use Mark II motors 403 to meet the requirement of stronger vibration force and are installed in the center of the palm and the center of the back of the hand, respectively.

[0083] The fingertip portion consists of a fingertip moving platform 404 and a finger back fixing platform 405.

[0084] The finger back fixation platform is secured to the back of the distal phalanx by embedding it into the glove fabric, bonding it to the glove carrier, and binding the finger with an elastic bandage 406. The fingertip moving platform is connected to the finger back fixation platform by a spring 407 that can rotate back and forth around the connection point, preventing the platform's gravity from affecting the fingertip pressure and contact area after changes in hand posture. The fingertip moving platform uses soft silicone as a base 408, with some actuators and sensors mounted or embedded in the silicone base. Along the direction outward from the fingertip skin, the components are, in sequence: contact surface silicone 409, variable curvature actuator 410, pressure sensor 411, and linear vibrator 412. The finger back actuation fixation platform is equipped with three small servo motors 413. Two of these servo motors, fitted with planetary gearboxes, use high-elasticity cables 414 to pull the moving platform from both sides, controlling its movement in the left-right and up-down directions. The third servo motor is connected to the moving platform via a crank 415, controlling its forward-backward movement.

[0085] The instruction control unit and the signal driving unit together constitute the driving circuit of the tactile glove device. The following describes a specific embodiment of the driving circuit:

[0086] In the instruction control unit, an STM32 chip and its minimum system circuit are used as the processor module, a rechargeable lithium battery module is used as the power supply module, and a Bluetooth module is used as the signal transmission module. In the signal drive unit, an eight-channel eight-bit digital-to-analog converter (DAC) and a first-order low-pass active filter composed of capacitors, resistors, and an OPA1678 operational amplifier, along with a voltage linear amplifier, are used as the signal processing module and voltage amplification module. An OPA547 operational amplifier and an L298 motor drive module are used as the power amplification module to drive the linear vibrator and servo motor, respectively. The drive signals are finally transmitted to each driver through a flexible circuit. Figure 3 This is a block diagram of the drive circuit.

[0087] Figure 4 This is a flowchart of the haptic reproduction rendering method, which mainly includes the following:

[0088] The haptic feedback rendering at the fingertip position uses vibration stimulation to render contours and textures, normal pressure stimulation to render elasticity, and fingertip skin tangential force stimulation to render friction. Among them, vibration stimulation is divided into multiple rendering scenarios according to different stages, including contour vibration in the contour stage, contact vibration, edge vibration, and texture vibration in the contact stage, and penetration warning vibration in the penetration warning stage. Normal pressure stimulation and fingertip skin tangential force stimulation are both in the contact stage.

[0089] Non-fingertip haptic feedback rendering uses vibrators installed on other non-fingertip areas such as the proximal knuckles of the fingers, the palm, and the back of the hand to generate haptic vibrations to render impact, virtual object outlines, and flowing gas or liquid.

[0090] Figure 5 This is a diagram illustrating the stages of fingertip haptic rendering. It divides the interaction process between a finger and an object surface in virtual space into four stages: no haptic effect stage, outline stage, contact stage, and penetration warning stage.

[0091] The following are the specific steps for dividing the fingertip haptic rendering stage: First, obtain the judgment distance parameter L. f The specific method involves obtaining the spatial coordinates P of the center point of the fingertip in virtual space. A circle with a radius of 0.5cm is then constructed along the fingertip's tangential direction, centered at point P. This circle is called the fingertip circle. Twelve points are then evenly distributed along the fingertip circle and are called fingertip points, with their spatial coordinates P. i Let i be 1 to 12. Starting from the 12 fingertips, find the minimum distance L from each fingertip to the surface of the virtual object. i The degree is given by , and i ranges from 1 to 12. The minimum distance among the 12 fingertip points is selected as L, representing the distance from the fingertip to the surface of the virtual object. f When the fingertip is outside the object L f If the value is positive, L is inside the object. f It is a negative value. Then, the stages are divided: when L f ∈[0.5×l1,+∞), representing the stage without tactile effect; when L f ∈[0.2×l2,0.5×l1), which is the contour stage; when L f ∈[-0.5×l³, 0.2×l²), representing the contact stage; when L f ∈(-∞, -0.5×l3), which is the penetration warning stage; the length units above are all cm, and l1, l2, l3 are all coefficients that are not equal to 0.

[0092] Vibration stimulation is used to render contours and textures, generating tactile feedback in three stages: contouring, contact, and penetration warning. The drive signal output by the tactile feedback device to the vibrator is a standard waveform whose parameters such as amplitude A, frequency F, waveform W, and number of repetitions per cycle N are all controllable. The waveforms include sine waves, triangle waves, square waves, sawtooth waves, pulse waves, etc.

[0093] To obtain the functional relationship between the driving voltage and the maximum acceleration of the vibrator, taking a driving frequency of 200Hz as an example, the acceleration data of the linear vibrator is first measured when the amplitude of the sinusoidal driving voltage increases from 1V to 6V in 0.5V intervals at a fixed frequency of 200Hz. The maximum acceleration values ​​of ten cycles under steady state are selected from the acceleration data, and the average value is taken as the average maximum acceleration. A plot of the voltage amplitude A and the average maximum acceleration a is drawn on a Cartesian coordinate system, and the relationship is basically linear. The functional relationship is obtained by fitting a linear function, which is A = ba + g, where b is the vibration linearity coefficient and g is the vibration acceleration intercept. The above coefficients are related to factors such as driving frequency and vibrator structure. Figure 6 It is a curve showing the fitting of the driving voltage and maximum acceleration data of the vibrator.

[0094] The following describes the methods for rendering tactile sensations from fingertip vibration stimulation and generating vibration stimulation driving signals at each stage:

[0095] The tactile feedback from vibration stimulation in the profiling phase aims to indicate the approximate size and shape of the virtual 3D object to the user, helping them quickly locate the relative position of their finger to the virtual object and control their finger to rapidly enter the contact phase. The design and rendering methods for the drive signal parameters required for vibration tactile feedback in the profiling phase are as follows:

[0096] In the contouring stage, a standard sine wave is used as the driving signal for the contouring vibration. When the driving signal frequency is F1, the functional relationship between the maximum acceleration of the vibrator and the driving voltage is: A = b1a + g1, where b1 is the linear coefficient of the contouring vibration and g1 is the intercept of the contouring vibration acceleration. The intensity of the contouring vibration needs to increase as the distance between the fingertip and the surface of the object's contour decreases; therefore, the acceleration a generated by the vibrator... s The distance L from the fingertip to the surface of the virtual object f Functions: Where a s0 For the initial profile vibration acceleration, a s1 To obtain the maximum profile vibration acceleration, the driving signal voltage for the fingertip vibrator during the profile vibration phase is:

[0097] The tactile feedback during the contact phase of vibration stimulation aims to render the tactile effects of fingertips contacting the contours of objects, fingertips touching sharp edges of objects, and fingertips touching the surface texture of virtual objects. This helps users perceive the tactile characteristics of 3D object contour contact, contour edges, and surface texture, enhancing the realism and immersion of tactile interaction. The design of the driving signal parameters and the rendering methods required for vibration tactile feedback during the contact phase are as follows:

[0098] (1) Using vibration stimulation to render the contact between the fingertip and the virtual object contour surface: When the finger moves from the contour stage to the contact stage, the vibrator needs to generate a vibration tactile feedback that simulates a collision or contact sensation. The drive signal used is set to a single-cycle repetition N. c N pulse signals or other standard waveforms c To achieve a relatively small value, the duration of the entire vibration feedback needs to be controlled to be less than 0.2 seconds, as vibrations exceeding 0.2 seconds will weaken the impact felt on the human body. Specific parameters are obtained through subjective experiments. The frequency is defined as a constant, and the specific frequency parameter F2 is obtained through subjective discrimination and realism experiments. The functional relationship between the maximum acceleration of the vibrator and the driving voltage at frequency F2 is obtained, i.e., A = b²a + g². The contact vibration of the contour surface needs to simulate and render the impact, therefore the acceleration a generated by the vibrator... c A maximum acceleration a greater than 1.5 times the maximum profile vibration is required. s And the acceleration a c The normal component V of the fingertip velocity on the surface of the virtual object at the instant of the stage change. n The function is given by the acceleration expression as: a s =a c0 ×V n +1.5(a s1 +a s0 ), where a c0 The collision velocity is used as a reference acceleration. The fingertip vibrator drive signal voltage at the time of contact collision is obtained as: A c =b2[a c0 ×V n +1.5(a s1 +a s0 )]+g2, where b2 is the linear coefficient of contact collision vibration and g2 is the intercept of contact collision vibration acceleration.

[0099] (2) Use vibration stimulation to render the outline edge of virtual objects: When the finger approaches the outline edge of the virtual three-dimensional object during the contact phase, the vibrator needs to generate continuous, sharp and pressure-like vibration tactile feedback.

[0100] First, the outline edge of the virtual 3D object is obtained, and the conditions for providing vibration feedback on the outline edge are defined. The spatial line segment generated by the intersection of two or more surfaces with discontinuous curvature of the virtual object is considered as the outline edge of the virtual 3D object. When the distance L from the 12 fingertip points to the outline edge line segment... e Satisfy L e When ∈ [-0.5×l3, 0.2×l2), provide the user with vibration feedback of the contour edge.

[0101] The drive signal used for contour edge vibration feedback is set to a standard sine wave or other standard waveform, with a fixed frequency. The specific frequency parameter F3 is obtained through subjective discrimination and realism experiments. The functional relationship between the maximum acceleration of the vibrator and the drive voltage at frequency F3 is obtained, i.e., A = b³a + g³. The intensity of the contour edge vibration needs to be adjusted according to the distance L from the fingertip to the contour edge. e The acceleration a generated by the vibrator is set to increase as the value decreases. e The distance L from the tip of the finger to the edge of the virtual object's outline e Functions: Where a e0 For the initial edge vibration acceleration, a e1 To add maximum edge vibration acceleration, the fingertip vibrator drive signal voltage is obtained when rendering the outline edge of a virtual object: Where b3 is the linear coefficient of edge vibration and g3 is the intercept of edge vibration acceleration.

[0102] Figure 7 This is a schematic diagram of a method for rendering surface textures using fingertip vibration stimulation. When a finger moves tangentially on the surface of a virtual 3D object during the contact phase, the vibrator needs to generate continuous and subtle tactile vibration feedback to render the surface texture. The method for generating the texture vibration driving signal during the contact phase is as follows:

[0103] First, obtain the texture grayscale information of the virtual object's surface. Then, change the voltage of the vibrator drive signal based on the grayscale information. The specific method is as follows: Taking the fingertip surface contact point P... s Using a central point, obtain the grayscale matrix H of the "texture map" or "normal height map" of the object's surface within a square region with a side length of 5cm. a The grayscale point extraction spacing is 0.05cm. The tangential component V of the fingertip velocity on the virtual object surface is obtained. t The distance d that the fingertip moves during the time interval t0. This setting is only applied when V... t ≥V t0 Furthermore, the vibrator can only generate haptic feedback for rendering textures when d ≥ d0, and at this point, the first grayscale matrix H is generated. a2 Furthermore, within this range, a new grayscale matrix H is obtained for every 2.5cm movement of the fingertip. a2The previously acquired grayscale matrix became H. a1 The grayscale matrix is ​​normalized to obtain a normalized grayscale matrix. Where H n (x,y) is the normalized gray matrix H n The element in the x-th row and y-th column, H a (x,y) is the gray matrix H a The element in the x-th row and y-th column, h amax and h amin The grayscale matrix H is respectively a The maximum and minimum values ​​of the elements in the matrix. The normalized grayscale matrix H is retrieved every time interval t1. n2 P, the point of contact between the middle finger and the object surface s Normalized gray level h nt The newly obtained normalized gray level is h nt2 The previously obtained normalized gray level was h. nt1 The driving signal used for the vibration haptic feedback of the rendered texture is set to a continuous pulse wave with a very short duration or a high-frequency sine wave. The specific duration t2 and frequency parameter F4 are obtained through subjective discrimination and realism experiments. The functional relationship between the maximum acceleration of the vibrator and the driving voltage at frequency F4 is obtained, i.e., A = b4a + g4. The vibration intensity of the rendered texture needs to increase as the distance between the fingertip and the object's contour surface decreases; therefore, the acceleration a generated by the vibrator is set... t The distance L from the tip of the finger to the edge of the virtual object's outline f and normalized gray level h nt2 Functions:

[0104] Where a t0 For the background noise texture vibration acceleration, a t1 Let a be the initial texture vibration acceleration. t2 To add maximum texture vibration acceleration, m t This is the reference coefficient for texture vibration. Acceleration a t The value is refreshed every t1 time interval. The voltage of the fingertip vibrator drive signal when rendering the surface texture of a virtual object is:

[0105]

[0106] Where b4 is the linear coefficient of texture vibration and g4 is the intercept of texture vibration acceleration.

[0107] The tactile feedback during the penetration warning phase of vibration stimulation aims to provide users with a warning message that their finger has penetrated the surface and entered the interior of the object. This helps users quickly determine the relative position of their finger to the virtual object and control their finger to rapidly withdraw from the virtual object. The design and rendering methods for the drive signal parameters required for the vibration tactile feedback during the penetration warning phase are as follows:

[0108] The drive signal used for the penetration warning vibration is set to every time interval t W1 The duration of one playback is t. W2 The signal is a sine wave or other standard waveform. The standard waveform frequency is defined as a constant value, and the specific frequency parameter F5 is obtained through subjective discrimination and realism experiments. The functional relationship between the maximum acceleration of the vibrator and the driving voltage at frequency F5 is obtained, i.e., A = b5(a) + g5. The penetrating warning vibration is a kind of suggestive tactile feedback; therefore, the vibration intensity is related to the distance L. f finger normal velocity V n Regardless of parameters, the acceleration a generated by the vibrator w The functional relationship is: a w =m w ×a w , where a w For the initial penetration warning vibration acceleration, m w The penetration warning coefficient is given. The driving signal voltage of the fingertip vibrator during the penetration warning stage is: A. w =b5(m w ×a w b5 is the linear coefficient of the penetration warning vibration, and g5 is the acceleration intercept of the penetration warning vibration.

[0109] Normal pressure stimulation is used to render elasticity, specifically the elastic force exerted by the object's surface on the finger. This tactile feedback is generated only during the contact phase. The tactile feedback device outputs a voltage drive signal to the fingertip pressure actuator. The tactile rendering method of normal pressure stimulation is explained in detail below.

[0110] The fingertip normal pressure F generated by the fingertip pressure actuator is controlled in a closed loop based on the pressure data collected by the pressure sensor. n Normal pressure F at the fingertips n Distance L from fingertip to virtual object surface f The functional relationship is: F n =(0.2l2-L) f )×k n ×F n1 +F n0 , where k n F is the stiffness coefficient of the virtual object. n1 To add the maximum fingertip pressure coefficient, F n0This is the initial fingertip pressure coefficient.

[0111] The following describes the tactile rendering method of fingertip tangential force stimulation during the contact phase:

[0112] Finger-tip tangential force stimulation is used only during the contact phase to render the frictional force and direction generated by the tangential movement of the finger on the object surface. The X-axis and Y-axis motion actuators used control the moving platform to provide tangential traction force to the fingertip skin without relative displacement with the skin. The X-axis and Y-axis motion actuators can each generate the same maximum unidirectional tangential skin force F at the same maximum voltage. t0 The functional relationship between the driving voltage applied to the directional movement actuator and the generated tangential force on the skin is A. t =b6F t +g6, where b6 is the linear coefficient of the tangential force and g6 is the intercept of the tangential force. This obtains the tangential component V of the fingertip velocity on the surface of the virtual object. t Tangential velocity components V in the X and Y directions respectively tx V ty The expressions for the driving voltages applied by the X-direction movement actuator and the Y-direction movement actuator are as follows:

[0113] To overcome the problems of slow start-up and stop times, weak initial vibration, and delayed stopping vibration in conventional control of vibrators, the drive signals applied to the vibrator in the above three stages are preprocessed. The preprocessed signals are then sent to the vibrator as the actual vibration drive signals. The specific method is as follows:

[0114] The drive signal applied to the vibrator is preprocessed, and the preprocessed signal is sent to the vibrator as the actual vibration drive signal. When the vibrator needs to switch from a non-vibration state to a vibration state or from a low-acceleration vibration state to a high-acceleration vibration state, the newly applied vibration drive signal is preprocessed. The specific startup algorithm is to increase the voltage amplitude of the first two cycles of the newly applied vibration drive signal to twice the original value. Figure 8 This is a schematic diagram of the preprocessing of the vibrator drive signal.

[0115] When the vibrator needs to switch from a vibrating state to a non-vibrating state, the last applied vibration drive signal is preprocessed to stop. The specific stopping algorithm is as follows: the last applied vibration drive signal is extended for one cycle, the phase of the signal is shifted by 180°, and the voltage amplitude is reduced to half of the original value. Figure 9 This is a schematic diagram of the preprocessing for stopping the vibrator drive signal.

[0116] The following describes the haptic feedback rendering method for non-finger-tip locations. Figure 10A schematic diagram of the non-finger-tip tactile rendering method.

[0117] The method for non-finger-tip vibration stimulation tactile rendering and vibration stimulation driving signal generation is as follows: Vibrators installed on other non-finger-tip parts such as the proximal knuckles of the fingers, the palm, and the back of the hand are used to generate vibration tactile sensations to render impact, virtual object outlines, and gas or liquid in a flowing state.

[0118] The impact force is rendered using a vibration motor located in the center of the palm or the center of the back of the hand. The drive signal is set to an amplitude-modulated wave with an exponentially decaying envelope. Only the first three cycles are output, and the carrier frequency parameter is F. hv Obtain the relative velocity V between the palm and the object. c The expression for the driving signal of the palm vibrator, based on the mass M of the object, is as follows:

[0119]

[0120] An array of vibrating motors located in the palm, back of the hand, inner side of the proximal knuckles of the fingers, and outer side of the proximal knuckles of the fingers are used to render the tactile sensation of the hand contacting the outline of a virtual object. The drive signal is set to a frequency parameter of F. tv The standard sine wave. The intensity of each vibration motor varies with the distance L between the motor's position and the surface of the virtual object. tv And changes, and L tv Given the range [-0.5×l³, 0.2×l²), the expression for the driving signal of a single vibrator is obtained as follows:

[0121] A tv =(k tv ×|L tv |+k tv0 )×sin(2π×F tv ×t), where k tv k is the contact vibration amplification factor. tv0 This represents the initial amplitude of the contact vibration.

[0122] An array of vibrating motors located in the palm, back of the hand, inner side of the proximal knuckles of the fingers, outer side of the proximal knuckles of the fingers, and fingertips renders the tactile sensation of gas or liquid flowing through the hand. The drive signal applied to each vibrator is a single-cycle repetition with a frequency parameter of F. fv The standard sinusoidal waveform. The first vibrator in the direction of the virtual gas or liquid flow has a sinusoidal wave phase of 0 and generates a single-cycle vibration. Other vibrators are based on their mapping distance d from the first vibrator in the flow direction. v The difference and flow velocity v f The different phases of the driving signals from each vibrator cause delayed vibrations. The change is as follows: In the formula This represents the fluid vibration delay coefficient. After each vibrator completes its vibration in sequence and the vibrator with the largest mapping distance completes its single-cycle vibration, the above process is repeated to begin a new round of vibration.

[0123] The experimental methods for subjective discrimination and realism are as follows:

[0124] The above haptic rendering requires determining the frequencies of multiple vibrator drive signals under different rendering scenarios, namely, the profilometry vibration frequency parameter F1, the contact collision vibration frequency parameter F2, the edge vibration frequency parameter F3, the texture vibration frequency parameter F4, the penetration warning vibration frequency parameter F5, and the palm impact vibration frequency parameter F6. hv , contour contact vibration frequency parameter F tv The vibration frequency parameter F of gas-liquid flow fv The frequency range of 20 to 800 Hz was divided into 40 frequency points in 20 Hz intervals. These 40 frequency points were randomly assigned to the above frequency parameters. For each frequency parameter, the following experiment was conducted: Ten adult subjects with normal tactile sensation were selected. With minimal difference in subjective vibration sensation at each frequency point, each subject, wearing tactile gloves, conducted a tactile rendering perception experiment. By comparing the tactile sensation with other rendering scenarios, they freely adjusted the frequency point corresponding to that frequency parameter based on their subjective feelings. After all 10 subjects had adjusted and selected the above frequency parameters, each subject subjectively scored the frequency parameters set by the other subjects, considering both discrimination and realism, with scores ranging from 1 to 10. The discrimination and realism scores for each frequency parameter were averaged, and the frequency point with the highest score was selected as the frequency value of that parameter.

[0125] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A rendering method for a haptic glove based on vibration and skin displacement control, characterized in that: A mathematical mapping model is established between the interactive feature parameters of 3D objects in virtual space and the tactile signal parameters. A glove-style tactile reproduction device is used with a specific rendering method to provide users with tactile sensations such as the outline, softness, surface texture, impact force, and fluid flow of 3D objects. This rendering method is as follows: (a) Tactile feedback rendering method at the fingertip: Vibration stimulation is used to render contours and textures, normal pressure stimulation is used to render elasticity, and tangential force of the fingertip skin is used to render friction; specifically, it includes the following steps: 1) The interaction process between fingers and object surfaces in virtual space is divided into four stages: no tactile effect stage, outline stage, contact stage, and penetration warning stage. The specific stage division method is as follows: obtain the spatial coordinates of the center point of the fingertip in virtual space. ,by Construct a circle with a radius of 0.5cm along the fingertip's cross-section, centered at the point. This circle is called the fingertip circle. Take 12 points evenly distributed along the fingertip circle, called fingertip points, with spatial coordinates as follows: , The range is 1 to 12; using 12 fingertips as starting points, the minimum distance from each fingertip to the surface of the virtual space object is calculated, and the fingertip distance length is... , The distance is 1 to 12; the minimum value among the 12 fingertip distances is selected as the distance from the fingertip to the virtual object surface. When the fingertip touches the outside of the object A positive value indicates that the object is inside. It is a negative value; The corresponding intersection point with the object's surface is called the surface contact point. ; according to The value determines the current stage of the interaction process the finger is in, specifically: when... This is the stage without tactile effects; when This is the outline stage; when This is the contact phase; when This is the penetration warning stage; all length units above are in centimeters. , , All are coefficients that are not equal to 0; 2) Calculate the required driving signal voltage amplitude for vibration tactile feedback during the contouring stage based on the finger position: ； in For the initial profile vibration acceleration, To add maximum profile vibration acceleration, The linear coefficient of the profile vibration. The intercept of the profile vibration acceleration; 3) The driving signal required for vibration tactile feedback during the contact phase: (1) When the finger moves from the outline stage to the contact stage, the vibrator generates a simulated collision or contact sensation as a tactile feedback. The amplitude of the fingertip vibrator drive signal voltage during the contact collision is: ； in, As a reference acceleration for collision velocity, The normal component of the fingertip velocity on the surface of the virtual object at the moment of stage change. For the linear coefficient of contact collision vibration, The intercept of the contact collision vibration acceleration; (2) When the finger approaches the outline edge of the virtual three-dimensional object during the contact phase, the vibrator generates continuous, sharp, and pressure-sensitive tactile feedback. The amplitude of the fingertip vibrator drive signal voltage when rendering the outline edge of the virtual object is: ； in For the initial edge vibration acceleration, To add maximum edge vibration acceleration, The linear coefficient for edge vibration. The intercept of the edge vibration acceleration; (3) When the finger moves tangentially on the surface of the virtual three-dimensional object during the contact phase, the vibrator generates continuous and delicate tactile feedback to render the texture of the object surface. The amplitude of the fingertip vibrator drive signal voltage when rendering the texture of the virtual object surface is: ； in, To normalize the grayscale of the old, For the new normalized grayscale, For the vibration acceleration of the background noise texture, The initial texture vibration acceleration, To add maximum texture vibration acceleration, For texture vibration reference coefficients; driving voltage The value every The time is refreshed once. The linear coefficients of texture vibration, The intercept of texture vibration acceleration; 4) Calculate the driving signal voltage amplitude required for the vibration tactile feedback during the penetration warning stage based on the finger position. : ； in, For initial penetration warning vibration acceleration, Penetration warning coefficient, For the penetration warning vibration linearity coefficient, To penetrate the warning vibration acceleration intercept; 5) Preprocess the drive signal applied to the vibrator to overcome the problems of slow start-up and stop times, weak initial vibration, and delayed stop vibration. The specific method is as follows: When the vibrator switches from a non-vibrating state to a vibrating state or from a low-acceleration vibration state to a high-acceleration vibration state, the voltage amplitude of the first two cycles of the newly applied vibration drive signal is increased to twice the original value; when the vibrator switches from a vibrating state to a non-vibrating state, the last applied vibration drive signal is extended for one cycle, the phase of the signal is shifted by 180°, and the voltage amplitude is reduced to half the original value. 6) The contact phase normal pressure stimulation tactile feedback is used to render the elasticity of the object; the fingertip pressure actuator generates fingertip normal pressure. for: ； in, This represents the stiffness coefficient of the virtual object. To add maximum fingertip pressure coefficient, This is the initial fingertip pressure coefficient; 7) During the contact phase, the tactile feedback stimulated by the fingertip tangential force is used to render the frictional force and its direction. The expressions for the driving voltage applied by the X-direction and Y-direction motion actuators are as follows: ， ； in, This represents the tangential component of the fingertip velocity on the surface of the virtual object. , This represents the tangential components of the fingertip velocity along the X and Y directions on the surface of the virtual object. The maximum unidirectional tangential force on the skin. The linear coefficient of tangential force. The tangential force intercept; (ii) Haptic feedback rendering method for non-fingertip locations: Using vibrators installed on other non-fingertip locations such as the proximal knuckles of the fingers, the palm, and the back of the hand to generate tactile vibrations to render impact, virtual object outlines, and flowing gas or liquid; specifically including the following steps: 1) Use a vibration motor located in the center of the palm to render the impact force. The envelope is in the form of exponential decay. Only the first three cycles are output, along with the carrier frequency parameters. The relative velocity between the palm and the object was obtained through subjective discrimination and realism experiments. Mass of an object The driving signal expression for the palm vibrator is constructed as follows: ;in The impact strength coefficient; 2) Use an array of vibration motors located in the palm, back of the hand, inner side of the proximal knuckles of the fingers, and outer side of the proximal knuckles of the fingers to render the tactile sensation of the hand contacting the outline of a virtual object. The intensity of each vibration motor varies with the distance between the motor and the surface of the virtual object. As this changes, the expression for the drive signal of a single vibrator becomes: ； in, This is the contact vibration amplification factor. This represents the initial amplitude of the contact vibration. 3) An array of vibrating motors located in the palm, back of the hand, inner side of the proximal phalanx of the fingers, and outer side of the proximal phalanx of the fingers are used to render the tactile sensation of gas or liquid flowing in the hand. The driving signal applied to each vibrator is a single-cycle repetitive standard sine wave. The first vibrator in the direction of the virtual gas or liquid flow has a sine wave phase of 0 and generates a single-cycle frequency of [frequency value missing]. The vibration of the other vibrators is determined by their mapping distance from the first vibrator in the flow direction. Differences and flow rates The different phases of the same-frequency single-cycle oscillations, which are delayed due to their different frequencies, affect the phase of the driving signals of each oscillator. The change is as follows: In the formula This is the fluid vibration delay coefficient.

2. The rendering method for the haptic glove based on vibration and skin displacement control according to claim 1, characterized in that: The glove-type tactile reproduction device comprises an audiovisual presentation unit, a computing unit, a posture sensing unit, a tactile interaction unit, a command control unit, and a signal driving unit, wherein: The posture sensing unit acquires information such as the user's hand position, posture, and fingertip pressure, and transmits it to the computing unit. The computing unit processes the sensing data and calculates and generates the user's hand model and virtual 3D object in real time in the virtual 3D space. It uses haptic rendering methods to generate drive commands for each actuator and transmits audiovisual data to the audiovisual presentation unit and drive command data to the haptic interaction unit. The audiovisual presentation unit presents the scene of the virtual 3D space to the user through video and sound, helping the user to judge the relative position of the virtual hand and the virtual 3D space based on their own proprioception and perform synchronized interactive actions. After receiving the drive command data, the command control unit controls the signal drive unit to transmit drive signals for each actuator to the haptic interaction unit, so that the haptic interaction unit can provide tactile stimulation to the user and reproduce the tactile sensation.

3. The rendering method for a tactile glove based on vibration and skin displacement control according to claim 2, characterized in that: The tactile interaction unit described herein is divided into a fingertip part and other parts, consisting of a carrier glove, a vibration tactile module, a fingertip pressure module, a fingertip three-degree-of-freedom skin displacement module, and a sensor module belonging to the posture sensing unit, used to provide tactile stimulation to the user and generate tactile feedback. In the aforementioned tactile interaction unit, other parts consist of vibrators embedded in the glove fabric or bonded to the glove carrier. The vibrators are located near the phalanges, fingertips, backs of the fingers, and the palm and back of the hand. The fingertip part consists of a fingertip moving platform and a finger back fixing platform. The finger back fixing platform is fixed to the back of the distal phalanx by embedding it in the glove fabric, bonding it to the glove carrier, or binding the finger with an elastic bandage. The fingertip moving platform and the finger back fixing platform are connected by a spring to prevent the weight of the moving platform from affecting the fingertip pressure and contact area after the hand posture changes. The fingertip moving platform uses soft silicone as a base, and some actuators and sensors are installed or embedded in the silicone base. The finger back fixing platform can optionally be equipped with actuators to control the movement of the moving platform.

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