方向感知定位系統與長期照護

Orientation-Aware Localization System for Long Term Elder Care

宋宜璟(Yi Jiing Song)

指導教授 ： 黃寶儀

國立臺灣大學/電機資訊學院/電信工程學研究所/碩士(2010年)

https://doi.org/10.6342/NTU.2010.02344

摘要

由於台灣已經步入了高齡化的社會，對於老年人的居住跟照護的需求也在增加當中，因此年長者的照顧也就更值得被重視。而在相關的研究當中，安養中心裡的年長者長期生活型態確很少被探索及調查，為了瞭解他們每天的生活，我們實際在北護護理之家佈建了以RSSI(接收信號強度)特徵為基礎的定位系統來追蹤年長者的定位資訊。
我們的定位系統是採用指紋特徵的概念，主要原理是將從tag收到的RSSI向量跟事前收集的RSSI值做比對藉以推測位置。然而無線訊號會被人體阻檔，因此這類的定位系統準確度降低的主要原因是在training(訓練) 階段與tracking(追蹤)階段方向不一致所造成的。我們提出了方向感知的定位系統來改善此問題，利用陀螺儀感測器來偵測使用者的方向，只有相同方向的RSSI 特徵才會被選出來做比對進而算出定位估測值。實驗結果顯示有考慮方向的系統大幅改善了定位準確度。
另一方面，我們收集了長期的定位資訊來分析年長者的生活起居的形態，藉由這些資訊，我們發現年長者對於空間使用的多元性不足，因為他們在一天當中花了大部份的時間在房間及交誼廳。

關鍵字

陀螺儀 ； 方向感知 ； RSSI特徵 ； 指紋特徵

並列摘要

Since Taiwan has become the aging society, the demand of living and nursing for senior citizen is increasing. Hence, it is necessary to pay attention on this research area. We are interested in the long term life behavior of the senior residents in the nursing home because it is rarely explored and investigated. To observe their life behaviors, RSSI signature based localization system has been deployed on the 5th floor of senior care center in Taiwan University Hospital Beihu Branch (abbreviated in “Beihu senior care center”) to provide their location traces.
Our localization system is a fingerprint type system. It maps between the RSSI vector received the tag and RSSI signatures pre-collected on the localization area to infer the location of tag. Due to RSSI may be blocked by the human body, the major factor for the accuracy degradation is due to the orientation inconsistence of the training phase and tracking phase. So, in order to get more accurate location estimations, we propose the orientation-aware localization. It uses the gyro to detect the heading information and only RSSI signatures having identical orientation are selected to find the possible location. The experiment result shows that there is a significant
improvement after considering the heading information.
On the other hand, we collect long term seniors’ location traces to analyze their life behaviors. We find out that they spent much of the time to stay in the bedroom as well as the living space so the diversity of their space usage is low.

並列關鍵字

Gyro ； orientation-aware ； RSSI signature ； fingerprint

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