The Design And Implementation Of The Distributed Miniature Life Detection System Based On Sound Wave

This thesis is from the commonweal scientific research project named the research of the emergency rescue equipments and the key parameters applied to earthquake disasters in 2007. The project whose code is 20070708052-03 is taken by Chengdu University of Technology and the institute of mitigating the earthquake disasters of Seismological Bureau in Sichuan province. The research workers of the project include professor Guo Yong, Chen Weifeng, Peng Jinchuan, Gao Song, Xie Xinghong, Lai Wugang and Li Zhipeng.Earthquake is one of the most destructive natural disasters to human beings in our life. And China is a country full of strong earthquake. Protecting against and mitigating earthquake disasters, which is linked with the life security of people and the sustainable development of the economy, is an important part of the public security of the state and is of significant essential common good. It will make great sense to our society to speed the protecting against and mitigating earthquake disasters.Because of the big volume, complicated operation and the bad effect of the present life detection devices, it is urgent to design a new kind of detection device with high performance. The system this paper introduces is such kind of device which is based on the former life detection devices our project team has designed, such as optical life detection, IR life detection and sound wave and vibration life detection devices. The system can be applied to life detection of greater area due to its wireless communication.The system is composed of detecting unit and receiving terminal. The detecting unit is a sound collector which is non-returnable after cast into the disaster scene and the number of it is set based on the specific area. The detecting unit is designed to collect the abnormal sound around it and then transmit it with wireless communication. The communication frequency of all the detecting units is different from each other and can be modified when necessary. The receiving terminal whose CPU is MSP430F149, a kind of SOC from TI corporation is designed to monitor the abnormal sound transmitted by the detecting unit and then position the source of the abnormal sound. The user can easily manipulate the receiving terminal with the good interaction between humans and computers.Due to the special desire of positioning of the life detection device, this paper discusses specially the present positioning technology and relative positioning algorithms home and abroad and then proposes an assumption to cast away a brick to attract the jade for the further design and research of the life detection device.By now the sample of the system has been finished and proved by some experiments. The detecting unit characterizes miniaturization, low power consumption and high sensitivity and meanwhile with the receiving terminal the user can speculate the rough position of the survivor based on the source of the abnormal sound. The system has been examined and accepted by the relative bureau. Compared with the former life detection devices, the system has got some initiative features, such as high stability, high responsiveness, wide coverage, universal usage and so on.It shows that the system can achieve the target of the assignment and meet the basic demand of advanced equipments desired in the field of emergency rescue. The system has good prospects and practical and commercial values.