Ultrasonic Tactile Rendering Method Based On 3D Virtual Objects

Tactile feedback provides a new interaction mode for human-computer interaction and is an important research direction in the field of human-computer interaction at present.The aerial haptic technology is capable of delivering tactile sensations without direct contact between the user and the tactile interface.In the research of air tactile feedback,the air tactile feedback based on ultrasonic radiation pressure is a hot spot at home and abroad.The aerial tactile feedback based on ultrasonic radiation pressure frees the user from the shackles of the device,increases the naturalness of interaction,and improves the comfort of interaction.It is widely used in many fields such as education,medical treatment,games and so on.This paper puts forward a kind of ultrasonic haptic rendering method based on grid model,and the strength of the local characteristics in the position of the method,the modulation waveform,frequency modulation for the subjective test experiment,through the experimental analysis of the local features to describe the positive role of rendering method,and through the contrast experiment and analyzes the effects of visual AIDS to the render method.It provides a technical reference for the recognition of virtual 3D graphics in ultrasonic-tactile rendering.The main work of this paper is as follows:(1)An ultrasonic tactile rendering method based on mesh model is proposed to complete the positioning of the ultrasonic focal point of the finger and the palm.A control point allocation method for multi-point ultrasonic focusing of virtual object is proposed.The method can ensure the tactile perception of local position of virtual object.By designing three groups of subjective test experiments,the intensity of ultrasonic focal points at vertices,edges and planes of virtual 3D graphics,the modulated waveforms(sine wave,triangular wave,square wave)and the optimal solution of parameters at each position are studied,and the positive influence of local feature description on the recognition of virtual objects is proved.(2)On the basis of the completion of the whole 3D virtual object based ultrasonic tactile rendering method,a comparative experiment is designed with or without local features to verify the effectiveness of the addition of local features on the shape recognition of virtual 3D graphics.The design based on virtual methods of ultrasonic haptic rendering 3D graphics and ultrasonic haptic rendering method of space-time modulation contrast experiment,and through the constraints of visual AIDS,of two rendering methods were tested and analyzed,verify the ultrasonic haptic rendering method based on 3D virtual object of validity,and under the condition of no visual AIDS in virtual object recognition robustness.Comparison experiments of the recognition rate of the two methods are designed to further verify the robustness of the ultrasonic tactile rendering method based on 3D virtual objects in the aspect of virtual object recognition.The main contributions and innovations of this paper include;(1)The method of combining mesh model and hand recognition device is proposed to complete the positioning of ultrasonic focal point of finger and palm and the distribution method of ultrasonic focusing control points.This method can flexibly adjust the tactile sensation of each position of the virtual object.(2)In ultrasonic haptic rendering methods of virtual objects,to join the local characteristics of the virtual 3D graphics,and through a lot of experiments on the local position of test data,determine the local position of specific modulation waveform,and the optimal values of intensity and frequency modulation,to verify the effectiveness of the virtual objects described by the local characteristics in the positive role of the virtual object recognition.(3)Complete the comparative experiment with and without local features,analyze the positive influence of local feature description on the recognition of virtual3 D mesh model,and complete the comparative experiment between the ultrasonic tactile rendering method of virtual 3D graphics and the ultrasonic tactile rendering method using space-time modulation.And the two methods of rendering visual AIDS were tested and analyzed the condition of ultrasonic haptic rendering method of virtual 3D mesh model and the influence of ultrasonic haptic rendering using space-time modulation methods,verified the ultrasonic tactile method based on virtual objects under the condition of no visual AIDS virtual object recognition robustness.The comparison experiment of the recognition rate of the two rendering methods is designed to further prove the effectiveness of the ultrasonic tactile rendering method based on virtual objects in the recognition of virtual objects.In this paper,the ultrasonic tactile rendering of virtual 3D objects is studied from the aspects of the basic theory,hardware conditions and rendering experiments of the aerial tactile feedback technology of ultrasonic radiation pressure,which provides technical support for the aerial ultrasonic tactile rendering research based on virtual3 D virtual objects.