利用觸覺技術來增強沉浸式體驗已經在虛擬實境中被廣泛採用。儘管此項技術可以成功地增強沉浸感，許多觸覺回饋裝置的成本仍然過高，裝置上的硬體也有其投射範圍與運作極限。在本論文中，我們利用視覺粒子特效來增強沉浸式環境中的風回饋體驗。透過整合視覺效果和觸覺回饋，我們利用觸覺錯覺的技術，以實現強化VR中之感受。首先，我們基於人對於風的感知將裝置的風速進行量化。在此之後，為了研究粒子效果在觸覺錯覺的強化效果，我們再進行了兩個實驗，分別改變粒子的速度及擴散範圍來探索沉浸式環境中風體驗的增減益效果。結果顯示在我們的風裝置下，可以將風量化為四個等級。另外在改變視覺上粒子的速度及擴散範圍後，分別有38.5%及42.6%的機會可以讓使用者感受到相對應的增減益效果。最後，我們的結果可應用於利用風作為觸覺回饋的VR應用程式中。

Utilizing the haptic technologies for enhancing the immersive experience has been widely adopted in the virtual reality (VR). Although the immersion could be successfully enhanced, the cost of many tactile feedback displays are still too high, and the hardware on the device also has its projection range and operating limit. In this thesis, we utilize particle effect with airflow-based tactile sensation for enhancing the haptic experience in the immersive environment. By integrating the visual effect and the haptic feedback system, we synthesize the visuotactile illusion to achieve enhanced sensory engagement in the VR. First, we conduct a user study to quantify the wind speed of our display based on people’s tactile sensation of the wind. After that, to show the potential of proposed technique, we conduct two user studies, where we adjust the speed and diffusion of particle, to explore the enhancement via the wind modalities on the immersive experience. Our results can be applied in VR applications, which utilize airflow-based tactile feedback for enhancement.

口試委員會審定書 #
誌謝 i
中文摘要 ii
ABSTRACT iii
CONTENTS iv
LIST OF FIGURES vi
LIST OF TABLES viii
Chapter 1 Introduction 1
Chapter 2 Related Work 3
2.1 Wind Feedback System 3
2.2 Tactile Illusion 5
Chapter 3 Design Consideration 7
3.1 Volume and Speed of Wind 7
3.2 Effective Area of Wind 7
Chapter 4 Implementation 8
4.1 Hardware 8
4.2 Design of Particle Effect 11
4.2.1 Physical Behavior 11
4.2.2 Visual Expression 12
Chapter 5 Evaluation 16
5.1 User Study 1: Quantization of wind speed 17
5.1.1 Pilot Study 1: Minimum wind speed that people can feel 17
5.1.2 Main Study: Quantization of wind speed 20
5.2 User Study 2: Enhancement on speed of particle effect 25
5.3 User Study 3: Expansion on diffusion of particle effect 33
Chapter 6 Conclusion 40
Chapter 7 Future Work 41
REFERENCES 42

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