Application of data fusion technology in quick measurement of grain moisture

The dielectric characteristics of grain were analyzed theoretically, capacitive structure transducer and capacitance measurement circuit were designed to measure grain moisture by differential frequency method. According to the analyses and experiments, the factors affecting the capacitance measurement circuit were studied. Data were collected for the ready made grain samples around three variables, i.e. differential frequency, temperature and compact degree, which relate to capacitance measurement and moisture. The statistic analysis method was exerted to study the optimal mathematical model. First, the variables that constitute the mathematical model were selected. Second, by analyzing the relationships between the measured variables, several fitting equations were established for further processing. Finally, one optimal fitting equation, which was the optimal mathematical model, was chosen by statistic analysis method. This data fusion method adopting multivariable regression analysis surrounding moisture, differential frequency, temperature and compact degree, has achieved comparatively satisfying results in measurement precision and repeating nature of moisture instruments.