隨著沉浸式頭戴顯示器的普及，利用虛擬實境的方式，學員可在任何地方與虛擬教練一同練習。並透過預先錄製好的三維太極拳動作，系統可提供更多元的動作資訊讓學員來學習該動作，如同時觀看多個不同角度的教練示範及個人化的動作播放速度的調控等。雖然頭戴顯示器可提供多種虛擬教練的視覺化方法，但欠缺學員本身自己的動作資訊，因此學員在虛擬實境中，並不知道自己動作是否錯誤。本研究基於行動式虛擬實境裝置，並利用沉浸式視覺化的方式，設計兩種不同觀看自身動作的方法：(1)視訊穿透式影像與(2)擴增鏡子。將學員自己本身的動作資訊以真實影像的方式傳入至虛擬實境中，讓學員在觀看虛擬教練動作的同時，亦可透過虛擬實境中的第一人稱的影像或第三人稱的擴增鏡子來觀看自己的肢體動作，進而達到在混合實境中，可檢視及修正自己肢體動作的機會。在本使用者研究的結果顯示，利用在虛擬世界中佔有75%的第一人稱真實影像是最合適的顯示方式，相較於沉浸式擴增實境，在這比例中使用者較感受不到任何不適，並可完成指定任務。另一方面，學員對於擴增鏡子來呈現自己的身體資訊覺得很有幫助；在動作表現的結果上面，擴增鏡子可有效增進手部動作之正確性。

As the popularization of immersive head-mounted display, students can practice with virtual instructors in any place with the help of virtual reality. The system can provide multiple information of motion with the pre-recorded digital performance of Tai-Chi Chuan, for example, simultaneous observation of multiple angles of demonstration by coach and personalized speed of motion playing. Head-mounted display provides multiple ways of visualization of virtual instructors, however, students lack their own motion information and didn’t know how much correctness of it was. This research based on mobile virtual reality device and used the immersive visualization to conduct two methods for observing their own movement: (1) Video See-Through Image and (2) Augmented Mirror. By transmitting the image of reality to the virtual environment, students can also observe their own limbs movement via images of 1st person view and augmented mirror (3rd person view) while observing the instructors. This process of guiding achieves the goal of watching and correcting the limbs movement in mixed reality environment. The result of this research shows that the most appropriate size of 1st person view is in 75% of virtual environment. In contrast to immersive augmented reality, users can finish the indicated task they asked to do without any kind of sickness in this size. On the other hand, student thought the augmented mirror is helpful to display the information of body. As the result on motion performance, augmented mirror brings more correctness to the upper limbs movement.

Chapter 1 Introduction 1
Chapter 2 Related Work 4
2.1 Physical Activity Training 4
2.2 Multi-View 4
2.3 Visual Guidance & Self-Image 5
Chapter 3 Mobile Tai-Chi Chuan Player in Mixed Reality 6
3.1 System Overview 6
3.2 Design Considerations 7
3.2.1 Best size of see-through window in mixed reality 7
3.2.2 Usage of augmented mirror 8
3.2.3 The placement of virtual instructors and augmented mirrors 9
3.3 Implementation 10
3.3.1 Hardware Configuration 10
3.3.2 Immersive Visualization in Mixed Reality 11
3.3.3 Motion Capture and Motion Comparison 13
Chapter 4 User Study 18
4.1 Size of see-through window 18
4.1.1 Study Design 18
4.1.2 Result 20
4.1.3 Discussion 23
4.2 Usage of augmented mirror 25
4.2.1 Study Design 25
4.2.2 Result 26
4.2.3 Discussion 29
Chapter 5 Conclusions and Future Work 32
Reference 34

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