Portable ultrasonic 3D tag system based on a quick calibration method

The ability to quickly construct a human activity observation system is necessary in order to conduct field research on human activities. The authors have developed an ultrasonic 3D tag system, which is a type of location sensing system for observing human activities. The present study attempts to establish a systematic method for quickly constructing an ultrasonic 3D tag system in various environments. A calibration function that is available in various environments is one of the basic functions of portable ultrasonic 3D tag systems. In the present paper, we propose several methods for calibrating the 3D positions of ultrasonic receivers placed arbitrarily in a daily-use environment. The proposed methods require a relatively small number of transmitters and are independent of room size. In addition, the methods proposed herein are compared and their respective advantages are discussed. A portable system based on the proposed methods is also described herein.