Haptic Rendering Methods Based On The Combination Electrovibration And Vibration Stimuli

The tactile representation technology is a new research hotspot in the field of human-computer interaction in recent years.It is a new sensory channel for humans to communicate with the virtual world after hearing and vision.It improves the reality and immersion of human-computer interaction.Among them,the surface tactile representation technology reproduces the tactile sensation on the surface of a multimedia terminal,so that users can experience tactile features such as texture,roughness,and hardness just by touching with their bare fingers.The haptic rendering technology establishes the perceptual model of these tactile features.And it is the key technology to determine the effect of haptic rendering methods.At present,the surface tactile representation technology is mainly based on three feedback mechanisms: electrostatic force tactile feedback,squeeze film effect tactile feedback,and vibration tactile feedback.Most of the existing haptic rendering methods are based on only one of the above-mentioned haptic feedback mechanisms,and reproduce a single tactile feature such as texture or roughness in a multimedia terminal.It has not been fully studied how to combine the application advantages of different tactile feedback mechanisms to reproduce rich tactile features in multimedia mobile terminals according to the tactile representation characteristics of each tactile feedback mechanism,which severely limits the realistic sense of surface tactile reproduction effect.This paper mainly studies the haptic rendering method that integrates two feedback mechanisms of electrostatic force and vibration.It aims to present rich tactile features in multimedia terminals by integrating the tactile rendering characteristics of the two feedback mechanisms.This method is based on the device platform independently developed by the research group,and focuses on the construction of haptic information acquisition devices,haptic information data collection and processing,and the establishment of tactile features and haptic stimulus signal mapping models to further improve the reality of surface haptic reproduction effects.The main contents of this paper are as follows:(1)Analysis the principle of electrostatic force tactile representation and vibration tactile representation,the working mechanism of tactile reproduction device combining electrovibration and vibration stimuli,and device performance parameters.Based on the tactile reproduction device,through the subjective perception experiment,the absolute detection threshold of vibration haptic feedback is 19.67 Vpp,and the discrimination detection threshold is 2.07 dB.It provides a theoretical basis and data reference for the subsequent research on haptic rendering methods.(2)Analysis the factors that affect the human tactile experience,and determines the three parameters of texture,roughness,and motion speed as the objects to be collected by the haptic information acquisition device.For the collection object,the overall structure scheme of the haptic information acquisition device is designed.According to the functional requirements of each unit in the device structure,the hardware design scheme,component selection,development program and upper computer interface are developed.And finally the construction of the haptic information acquisition device is completed.(3)Using the haptic information acquisition device to obtain tactile information of four material samples with different tactile senses: sandpaper,plastic net,notebook cover and mouse pad,and analyze the results of the collected data.The data samples are selected based on the collected raw data.The low-frequency components of the data caused by environmental effects are eliminated by filtering.The outliers in the data are removed by physical discrimination and statistical discrimination.Calculating the valid data samples retained in the original data provides data support for the subsequent modeling work of the haptic rendering method.(4)According to the tactile representation characteristics of the tactile reproduction device combining electrovibration and vibration stimuli,the realization scheme of the fusion rendering method is designed.The scheme uses electrostatic force tactile feedback mechanism to render texture features of materials and vibration tactile feedback mechanism to render roughness features of materials.The radial basis function neural network model is used to build the mapping model of motion velocity and texture feature and the mapping model of motion velocity and roughness feature respectively.The mapping model of texture feature and electrostatic stimuli signal and the mapping model of roughness feature and vibration stimuli signal were established respectively through subjective perception experiment.By this way,we present a haptic rendering method which can realize two kinds of tactile features: texture and roughness.Through the contrast perception experiment,the rendering method proposed in this paper and the existing rendering method of single rendering material texture feature were scored by the subjective scoring method of ten points.Through the analysis of the scores of 12 subjects,it is verified that the rendering method proposed in this paper has better tactile reproduction effect.The main innovations of this article are as follows:(1)The overall structure of the haptic information acquisition device is designed to realize the real-time collection of texture information,roughness information of the materials,and movement speed information during the acquisition process.(2)The conversion between the original collected data and the data required for rendering modeling is studied,and an effective data sample selection method and data processing method are proposed.(3)A mapping model of texture features and electrovibration stimuli signals and a mapping model of roughness features and vibration stimuli signals are established.A rendering method that can simultaneously display texture features and roughness features of materials is proposed.This paper proposes a haptic rendering method based on the combination electrovibration and vibration stimuli for materials,and realizes the simultaneous presentation of texture and roughness features of the material in the multimedia terminal,which significantly improves the reality of the haptic rendering effect and provides a reference for research and application of tactile representation technology.