中小型规模智慧农业物联网终端节点设计

为了能够向中小规模农业生产经营者提供深度定制的农业物联网技术,该研究研发了一种可用于农业设备信息化的智慧农业物联网终端节点。通过该终端节点将农业设备柔性接入物联网体系,并依托管理服务层App实现应用层App功能开发。系统硬件利用可编程片上系统的IP核重用技术实现对各种农业设备的接入,实现各农业场景中根据设备具体情况进行定制化应用。系统传输层采用LoRa广域网与蓝牙技术,支撑集中式与分布式农业管理服务体系。管理服务层App对底层节点设备操作与Android功能操作进行封装,实现应用层与底层功能结构的解耦,避免了应用层App开发时结构复杂、对底层功能结构变化适应性差、开发周期长等问题。实践应用结果表明,该农业物联网终端节点可有效实现对农业设备的接入,具有1500VDC的电磁隔离能力;节点的LoRa无线数据通道在无严重降雨的天气中数据包传输成功率接近100%,蓝牙可支持周围3m范围内的移动设备现场接入;管理服务层App可有效支撑应用层功能快速开发;在直连上位机模式下,应用层App到节点设备间的功能延时分别小于400与1 700 ms,系统运行稳定,功能支撑可靠。该方法可为国内中小规模农业经营者的物联网信息化建设提供支持与参考。

Design of terminal nodes for small and medium scale intelligent agriculture Internet of Things

Internet of Things (IoT) technology has been increasingly used in agriculture. However, most existing agricultural IoT technologies are focused on providing management and service applications to large scale agriculture. In order to provide customized agricultural IoT technology to small and medium scale agricultural producers and operators, an intelligent agricultural IoT terminal node can be used for flexible information upgrade of agricultural equipments and other related devices was designed in this study. The system consisted of terminal nodes and management/service layer App. Through a terminal node, agricultural equipments and other related devices could be flexibly connected to agriculture IoT information frameworks. The management/service layer App linked to terminal node hardware and support the rapid and low-cost development. In the hardware device layer of the system, the IP core reuse technology of system on programmable chip (PSoC) was used to realize the flexible adaptation and access to various agricultural equipments and other related device. The PSoC of terminal node was designed on Cypress''s PSoC 6 (PSoC6-CY8CPROTO-063-BLE). The long-range low-power wide-area network (LoRa LPWAN) technology was adopted in the system to build data transmission channels between terminal nodes, and the LoRa in terminal node was designed on LoRa wireless communication module based on Semtech''s SX1278. The nodes use low-power Bluetooth technology to enable mobile smart devices (e.g., smartphones, tablets, etc.) to access the terminal nodes and achieve distributed agriculture management, and the Bluetooth on the terminal node was based on the integrated Bluetooth module in the PSoC6. The management/service layer App encapsulated the operation of the underlying terminal node and Android functions. Android Content Provider component combined with SQLite database was used to realize the mapping relationship between different layers. The introduction of the management/service App made the development of application-layer App faster and more suitable for the diversified needs of agricultural IoT requirements. The system was tested in different agricultural application scenarios. The results showed that terminal nodes could effectively provide information upgrade to agricultural equipment and related devices through IP-core reuse technology, and the electromagnetic isolation capacity of the system reached 1 500 VDC, the success rate of data packet transmission of Lora wireless data channel of node was close to 100% in the weather without severe rainfall, and Bluetooth could support the mobile device field access within 3 m around, in the mode of directly connected upper computer, the function delay between application layer App and node equipment was less than 400 and 1 700 ms respectively, the system ran stably and the function support was reliable. This study can provide support and reference for the information construction of Internet of Things for small and medium scale agricultural operators.