| Summary: | 碩士 === 國立臺北科技大學 === 電機工程系 === 106 === The study is designed to integrate the Bluetooth Low Energy (BLE), humidity and temperature sensors, one demonstration of a chamber with one control board of one refrigerator and one ceramic heater powered by one stand-alone DC power supply, as well as the smart phone APP, for implementing the smart farm. The initial concept of the smart farm is using the miniature BLE device with humidity and temperature sensor to implement the connection between the smart phone and the manager. The farm manager can get the instantaneous and accurate environment temperature and humidity through APP, then base on his/her own farming experience to make the new set point to the environment control unit. The control unit will switch on or off as hysteresis to control the environment conditions. The hysteresis control operates in the range of the high limit and low limit at set point for humidity and temperature. In the future, the collected data from the farm upload to the cloud in order to record the plant growth status, the plant quality and production trend. It can offer the information to the manager for comparing the variety of the environment condition. The study can fulfill the trace capability as production records in daily detail. Furthermore, it can analyze the contribution to various plants from the combination of temperature and humidity to achieve the higher productivity, better crop quality, the yield rate control, less herbicide for environmentally friendly, regardless the climate change or unpredictable, dangerous, labor force shortage, etc. In this study, it establishes with six individual BLE sensor tags to simulate the manager patrolled the farm collecting the data from BLE sensor tags. The smart phone is the master, several BLE sensor tags are the slaves. The environmental humidity and temperature data are broadcasted from the BLE sensor tags in certain area; the smart phone listens and connects to the specific tag. The manager can read the data from the smart phone APP then send the new set points based on agricultural experience to BLE tag. The new set point from APP through BLE sends to the Micro Control Unit (MCU). The MCU turns on or turns off the environment condition equipments. Once the manager leaves the certain specific area, the particular tag is disconnected. Then the smart phone listens to the nearest tag and connects again to the smart phone repeating the procedure once more. The simulation is to make the big size green house, saving the energy, which keeps the constant farming environment as a plus value added. In addition, this study use hysteresis controller to form the feedback loop in order to control the temperature and the humidity. The refrigerator turns on by MCU while the humidity compares to set point from APP is higher, it turns off on the contrary. The ceramic heat plates turn on by MCU if the temperature compares to set point from APP is lower, and it turns off otherwise. From the experiments, it results in different humidity and temperature response time. Under the spatial measurement of this demonstration chamber, the refrigerator turns on and off as relative humidity 5% compared to set point, the ceramic heating plates turn on or off as 1oC. It takes longer time of humidity rather than temperature response. The humidity hysteresis time is approximately 10 minutes. The temperature hysteresis is around as 7 minutes. To ensure all the temperature and humidity measurement are accurate, we employ one FLIR reliable thermal scanner to confirm the measurements are correct. It confirms that without calibration, the temperature detected from BLE sensor tag compared to meter is +3.2oC, the humidity of tag compared to meter is +3%. After the calibration is completed, the temperature difference shrinks to +0.2oC between the reliable thermal scan humidity and temperature meter. In addition, the humidity is equivalent compared to a thermal scan meter without any difference. Furthermore, we have an open air in field-testing in one private tea garden in Hehuan Mountain, Nan Tou County. It is an open area not to able to drive the conditioner. It tests for the connection of star topology of several sensor tags. The labor force is quite limited in high altitude as 2,000 meters, since it is extremely boring without the entertainment and harsh environment. It occupies with numbers of employees only during the short-lived seasonal harvest. In rest of the year, it is difficult to employ the labors for farming. It is an urgent need for those tea field farmers to find the alternative automation to help farming in leisure time. After the field-testing, the farmer experienced the advantage of smart farm offering the real time humidity and temperature, they express the desires to have the next generation for the underground Internet of Things (IoT) for auto irrigation. It results in the purpose of the study is to offer the miniature portable BLE devices through the smart phone APP to control the farm environment. The size of the tag is only 3 cm x 4 cm. The smart phone accompanies with the manager scan and connects to BLE sensor devices for agricultural decision. In the future, it is used for production records to the clouds in order to fulfill the trace capability for different plant growths, achieve the greenhouse farming profitability, increase the plant productivity, make the management sustainability, enhance crop quality, and protect the environment friendly as an implementation for Precision Agriculture (PA).
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