提出了一种基于电容式湿度传感器的植物粉料含水率测量方法。由电容式湿度传感器和数据采集卡组成的测量系统获取植物粉料含水率数据,应用一阶差分法剔除奇异值后,通过惯性滤波法处理数据。由菊花粉含水率的13个测量值与烘干法测得的真值对比试验结果可知,测量值与真值之间的最大相对误差为1.61%,平均相对误差为0.76%,均小于5%(测量样品数为5时置信区间为95%),表明该方法能够用于测量低水分植物粉料的含水率。
A method of measuring moisture content for plant material powder based on HM1520LF capacitive humidity sensor was introduced. The raw data sequence of moisture content was acquired by measurement system which consists of capacitive humidity sensor and data acquisition card. After excluding alternative singular by one rank difference method, inertia filtering method was employed to process the data sequence. By accordingly comparing 13 measured values of moisture content with corresponding true values from the baking oven, the maximal relative error of moisture content between measured values and true values was 1.61% , and the average relative error was 0. 76% , both less than 5% ( confidence interval 95% for 5 samples). As a result, the method can be used to determine the low moisture content of plant material powder.