连续超声波位置跟踪器的设计原理及其在虚拟现实系统中的应用实现

Design of Position Tracker Using Continuous Ultrasonic Wave and Its Application in Virtual Reality

位置跟踪器是虚拟现实和其它人机实时交互系统中最重要的输入设备之一，它实时地测量用户身体或其局部的位置和方向并作为用户的输入信息传递给虚拟现实系统的主控计算机，从而根据用户当前的视点信息刷新虚拟场景的显示．基于连续调幅超声波相位差相于测距方法实现快速、高分辨率的动同态方法测量的原理，本文着重阐述了以连续超声波相位差相干测量法实现三维动态位置测量的原理、系统设计、实验结果。

Position tracker is one of the most critical input devices for human-machine interface utilities in virtual reality and other human-machine interation systems. It determines the opition and orientation of an object of interest (such asthe user's head) and passes the information to the host comuter in real time, which whws the virtual worid on the bois ofthe current visual point of the user. A dynamic position tracker based on continuous amplitude-modulated ultrasonic wave isdeveloped by means of the interferometric techniques. Its principles, technical implementation and experimental results are discussed. A prototype virtual reality system using the ultrasonic position tracker as an input device is also constructed and presented in the paper.