提升智慧工廠情境中 LoRaWAN 網路能源效率與資料新鮮度

Abstract

物聯網(IoT)的一個典型應用是智慧工廠，其中感測器節點通常會依靠電池來執行 收集工廠環境數據的任務。當裝置執行耗能的任務會使電池電量消耗快速，將造成人力更換電池的次數上升。因此，所需的物聯網裝置必須是節能的。在智慧工廠中，感測器節點在運行過程可能於傳輸路徑上會有障礙物阻擋，造成數據無法上傳。在這種情況下，將無法繼續 評估工廠的環境變化。因此，可持續性傳輸是重要的要求。在低功率廣域網路(LPWAN)技 術中，LoRaWAN 是滿足要求的最佳網路協議。本論文對 LoRaWAN 智慧工廠網路架構進行了 研究。本論文的應用場境適用於在智慧工廠中有會移動的設備，如:輸送帶或機器人。在輸 送帶或機器人上安裝一個 LoRaWAN 網關 (Gateway)，使其變成一個移動網關。透過這個移 動網關，可以縮短網關和終端設備之間的距離，從而使用終端設備可以使用最節能的傳輸參 數來上傳數據，達到節能的目的。此外，斷線的節點在幫助節點的協助下，其資料能夠持續地上傳到伺服器。本論文提出的網路架構是在 ChirpStack 上實現的，這是一個用於 LoRaWAN 的開源框架。本架構的效能已在國立臺灣師範大學(NTNU)的校園環境中得到了驗 證。實驗結果證明，所提出的網路架構可以減少終端裝置的能耗，並能實現網路的可持續 性。A typical application of the Internet of Things (IoT) is the smart factory, where sensor nodes rely on batteries to sense data from the factory environment. As the devices perform tasks that consume energy, eventually the batteries will run out of power. Therefore, the required IoT devices must be energy efficient. During the operation of the nodes in a smart factory, there may be obstacles that prevent the sensed data from being uploaded. In this case, it will be impossible to continue to evaluate the environmental changes in the factory. Therefore, sustainable transmission is an important requirement. In Low Power Wide Area Network (LPWAN), LoRaWAN is the best network protocol to meet the requirements. This thesis presents a study for the LoRaWAN smart factory network architecture. The application of this thesis applies to equipment that moves in a smart factory, such as a conveyor belt or a robot. The LoRaWAN gateway is placed on the conveyor or robot to make it a mobile gateway. Through this mobile gateway, the distance between the gateway and the end device can be shortened, so that the end device can use the most energy-saving transmission parameters to upload data to achieve energy saving. And by finding the best helper, the disconnected device can continuously upload data to the server with the help of the helper. The network architecture proposed in this thesis is implemented on ChirpStack, an open source framework for LoRaWAN. The network architecture for this design has been validated at National Taiwan Normal University (NTNU). And the experimental results have validated that the proposed network architecture can reduce the energy consumption of the end device and can achieve the sustainability of the network.