- 學位論文
無線多跳式自動化點名系統之設計與實作
Design and Implementation of Multi-hop Automatic Roll-Call System
摘要
「點名」在群體生活中是不可或缺的程序，藉由點名可以得知人員是否到齊。以現今的國小為例，每學期至少會舉辦一次校外教學，出發前或轉移地點時，無可避免都會以點名來確認人數。甚至在教學過程中，為確保沒有學童脫隊，也會進行點名。一天下來，點名的次數相當頻繁，耗時耗力。 本論文針對戶外的教學活動，提出一個以Arduino UNO結合nRF24L01+ 無線模組所設計的自動化點名系統，利用氾濫式廣播（broadcast by flooding）的方式發送點名訊息，並由學生節點自動回應點名，可在不中斷目前活動的情況下完成點名。 然而，無線通訊因環境地形或傳輸距離等限制，可能發生訊號無法傳達的狀況，進而影響點名的準確率。為減少這樣的失誤，系統加入多跳（multi-hop）的方式，利用中間節點協助將點名訊息傳送到訊號不易到達的節點，以降低因環境因素所造成的失誤。研究中透過一般隊形點名、轉角地形以及較長距離點名等實驗，驗證本系統除了可在短時間內完成點名，加入多跳機制，亦提高了點名的準確率及有效範圍。
並列摘要
It is sometimes a necessary procedure to call out the names of those enrolled in a class or group activity. A roll call allows a group leader such as a supervisor, teacher or tour guide to know if all group members are present. It is still commonplace that elementary school classes take field trips regularly. Inevitably, their teachers need to carry out a roll call to ensure that all class members are present before setting out from one location to another. Also a roll call is performed during the teaching session. In sum though some time and effort is required to carry out these roll calls periodically throughout the day doing so ensures that the students are safe. Now, this commonplace activity can be enhanced through the implementation of modern technology. This study proposes an automatic roll call system which utilizes an Arduino UNO microcontroller board with an nRF24L01+ wireless module disseminating its signal via a flooding algorithm so as to reach all possible nodes of a given system. The resultant system when utilized will allow a roll call to occur electronically and automatically without waste of time or effort. However, there are obstacles to implementation. Since transmissions over a wireless network may face limitations in specific environments due to distance or topographical or architectural features, application of the proposed system can be negatively impacted. Therefore, to alleviate these conditions and address these issues in addition to using broadcast by flooding, multi-hop technology which allows previously unreachable nodes to be accessed via intermediate nodes is implemented to better propagate dissemination of information within the network. Results of regular formation, corner formation and long-distance roll call experiments carried out utilizing the proposed system verify that the system does indeed achieve greater efficiency and speed as well as increasing the effective range of the system.