Large-term sensing system for agriculture utilizing UAV and wireless power transfer

Abstract

In recent years, in order to improve crop production and quality of agricultural operations, an “agricultural remote monitoring system” have been attracting a lot of attention. The existing studies have proposed an agricultural remote monitoring systems using Wireless Sensor Network (WSN). In the existing system, the environmental information is collected from a large number of sensor nodes installed in the farm using a low-power wireless communications (e.g., ZigBee, LPWA). However, in these systems, even when the low-power wireless technology is utilized, it is difficult to run permanently on batteries because the battery capacity is not infinity. In addition, in the case of a large-scale field, a large number of intermediate nodes should be installed in the field, hence the installation and operation costs are high.On the other hand, a wireless power transfer technology is evolving and equipment which is capable of supplying power to places dozens of centimeters away has been available. In addition, Unmanned Aerial Vehicles (UAV) that can fly stably for a long time and has a large loading capacity has appeared.Therefore, in this study, we propose and develop a wide-area sensing system for large-scale farms using a UAV, a wireless power transfer technology, and an energy-saving short-range wireless communication system (i.e., Bluetooth Low Energy (BLE)). The UAV flies autonomously to the location of sensor nodes that are widely installed in the large farm for collecting the sensor data. Here, the UAV is designed to supply the power to the sensor node to measure and send the environmental information using the wireless power transfer technology. It eliminates the need for periodic battery replacement of the sensor node, which reduces the cost of operating the system.Through the experimental evaluation using the developed system, it has been confirmed that the UAV can accurately be controlled by the proposed feedback control to land near the sensor nodes, and that the sensor nodes can be operated by the wireless power transfer from the embedded system of the UAV.