Capacitive Sensing Technique for Measuring Water Content of leaves

• Main Authors: Yi-Wei Hsiao, 蕭逸偉
• Other Authors: 陳加忠
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/68253472049886541187

碩士 === 國立中興大學 === 生物產業機電工程學系所 === 103 === In response to the issues of improving the quality of agricultural production, resolving the manpower shortage and so on. The real-time monitoring system applied in the agricultural production could effectively replace the empirical approach for management. Based on the quantitative data and the growth characteristics of plants, we could not only avoid human misjudgements, but also appropriately control the cultural environment. In the study, The parallel capacitor was used to measure and investigate the capacitance changes of tomato leaves in different moisture content. The method developed in this study then can be used in irrigation management. The results show that the appropriate distance between electrodes can effectively improve the accuracy of the measurement. The predictive moisture content models with three relative positions and 53 frequencies between 1k~5Mhz were built. After validations, the MAE of the best models of three types of the water content (RWC、EWT、Mw) is 0.04203, 0.01207, and 0.0970, respectively. Among these equations, Mw has the highest resolution. The capacitance decreased from the center to the tip of leaves. It indicated that the water on the leaves is non-uniform distribution.