简介：
Home Wireless Network Detects Elderly Tumbles
家用“老人跌倒检测系统”
科学家用无线信号为房间绘制出一幅“3D导览图“，可以远程监控屋内的任何异动。
撰文/播音 拉里•格林迈耶（Larry Greenemeier）
“I’ve fallen, and I can’t get up!”
“我摔了一跤，可我爬不起来了。”
Years ago, the best option for people in this position was to press a button on their monitoring device and call for help. But that’s not always possible, especially if such a fall renders a person unconscious.
从前若身陷这般险境，最好的方法就是按铃呼救。但这也不容易做到，特别是当你已经摔得不省人事的时候...
So electrical engineers at the University of Utah have come up with a fall-detection system that instead relies on wireless sensors placed around a room. The sensors emit wireless signals that bounce off of whatever’s in the room and create a 3-D map using radio tomographic imaging.
为解决这个难题，犹他大学的电气工程师们开发了一个“跌倒检测系统”。他们在屋子里布置了许多无线感应装置，装置发出的信号碰到任何东西都会反射回去，并织满整个房间。研究人员再利用射线断层成像技术，就能为房间绘制出一幅3D图像。
By setting the sensors at different heights, you can tell when someone is standing, sitting or lying down, and for how long. Once the room is mapped, you can program the system to send an alert whenever there’s a fall-like movement, or an unusual period of no movement.
只要调整传感器的高度，你便能分辨出呆在屋子里的人的姿态，以及他们保持这种姿势的时间。房间被“测绘”出来后，你可以在系统中编写程序，一旦系统侦测到任何类似跌倒的动作，或是房子里长时间没有任何动静时，传感装置便会发出警报。
The researchers presented their prototype system at a symposium in London.
研究人员在伦敦的一个研讨会上展示了他们的设计原型。
The technology has obvious application as a home monitoring system for the elderly. No need for them to wear a button on a string around their neck as a constant reminder that gravity is their enemy.
很明显，这套系统可以造福家里的老年人。有了它，爷爷奶奶们再不需在脖子上围一个带按钮的线圈，时刻提醒自己当心重力带来的危险了。
(题图来源：pt.ntu.edu.tw)
