Multimedia Terminal Tactile Display Method Based On Squeeze Film Effect

Squeeze film effect tactile feedback technology can make people feel the shape,texture and softness of displayed objects on touch screens,realize natural and real tactile reproduction.It has always been one of the central researches in the field of humancomputer interaction.The realization of haptic reproduction in multimedia terminals will promote the vigorous development of human-computer interaction.At present,the study of the squeeze film effect haptic feedback technology mainly focuses on tactile feedback experimental prototype production,squeeze film effect tactile force modeling analysis and squeeze film effect haptic rendering methods.However,the relative research on the squeeze film effect tactile feedback technology in multimedia terminals is relatively less.In this paper,aiming at the problem of small range interaction area of existing tactile feedback terminals,squeeze film effect tactile feedback device integrated in a multimedia terminal is designed and manufactured.The tactile feedback performance of the device was objectively evaluated through actual measurement experiments,and the relationship between the amplitude of the drive signal and the tactile force was obtained.The characterization provides a reference for squeeze film effect tactile rendering methods.This paper analyzes the form of the tactile force when the electrostatic force tactile feedback is combined with the squeeze film effect tactile feedback,explores the possibility of the two tactile feedback methods merging,and provide a reference for the study of multiple tactile feedback intergration.The main work of this paper is as follows:(1)Based on the squeeze film effect tactile feedback principle,various vibration modes of piezoelectric ceramics are analyzed,the appropriate vibration mode are selected,and the physical dimensions and material of piezoelectric ceramics are determined,and the size of piezoelectric ceramic is 28?8?0.8mm.The overall structure of squeeze film effect tactile feedback multimedia terminal is designed.(2)According to the requirement of squeeze film effect driving signal,the driving signal design principles is determined.Designed the squeeze film effect driving signal hardware circuit,including waveform generation circuit,amplitude adjustment circuit,high voltage amplifier circuit and power supply circuit.The actual circuit is manufactured.The squeeze film effect tactile feedback multimedia terminal is manufactured.(3)The usage methods of the direct digital frequency synthesis chip AD9834 are introduced,the data writing process of the AD9834 chip and the process of the overall drive signal synthesis program are described,complete signal type selection and set the frequency and phase of the signal.Utilize Microsoft MFC application framework to develop upper computer parameter setting program.Finally,the waveform,amplitude and frequency of the output signal were tested in combination with the hardware circuit and the upper computer parameter setting program.The hardware circuit can output a drive signal with an amplitude of 60 V,a current of 3A and a frequency of 100 KHz.(4)The relationship between driving signal and tactile force was simulated through Matlab platform.The objective evaluation method of squeeze film tactile feedback is introduced.A squeeze force measurement platform was built to study the mapping relationship between different driving signals and squeeze force in the interaction process.The squeeze force is 0.15 N when the driving signal is 60 V.Finally,a piezoelectric ceramic is pasted on an existing electrostatic force tactile feedback screen to create a tactile screen that combines electrostatic force and air pressure film effect,presentation form of merging force of the electrostatic force tactile feedback and the squeeze film effect tactile feedback is studied.And two haptic feedback technologies can be used together without interference.The main contributions and innovations of this paper are as follows:(1)The overall structure of a multimedia terminal prototype based on squeeze film effect haptic feedback is designed,a haptic feedback prototype of the squeeze film effect that can be used for the multimedia terminal is realize and provides a reference for squeeze film effect tactile feedback terminal development.(2)The mapping relationship between the driving signal amplitude and the squeeze force is studied,which provides a reference for the study of the squeeze film effect tactile rendering method.(3)The possibility of merging of electrostatic force tactile feedback and squeeze film tactile feedback is studied.The fusion force presentation form of electrostatic force and squeeze force is measured and analyzed,which provides a reference for the fusion of various tactile feedback technologies.The above work provides a reference for the design and manufacture of squeeze film effect haptic feedback multimedia terminal prototypes,the objective evaluation of squeeze film effect haptic feedback,and the integration of electrostatic force tactile feedback technology and squeeze film effect haptic feedback technology,with certain applications values.