基于微力测量的雾滴沉积量快速测量系统设计与试验

Design and test for a quick measurement system of droplet mass deposit based on micro force measurement

为不用示踪剂,测量各类药液雾滴沉积量,基于电阻桥式微力传感器,设计雾滴沉积量快速测量系统。标定试验表明,采样盒中雾滴沉积量与传感器输出电压成线性关系,决定系数达到0.999,在此基础上,建立计算模型。通过选择高精度传感器、杠杆对微力放大、减小摩擦阻力和优化软件设计,系统分辨率可达到0.003 3 mg/cm^(2)。系统与示踪剂法对比试验表明,水平面上和竖直面上相对误差为分别为5.13%和6.13%,有较高的测量精度。外界因素对测量的影响试验结果表明:环境温度、风速、采样液蒸发和农药种类等因素对测量精度影响较小。系统可为喷雾规律研究,提供高效测量方法,有较好应用前景。

A measurement system based on the electric resistance micro-force sensor was designed to measure droplet mass deposit promptly without using tracer.The calibration test results showed that there was a good linear relation between the droplet mass deposit and the output voltage of sensor,and the determination coefficient was 0.999,therefore,the calculation model was built to provide measurement basis for the system.To improve measurement resolution,the high-precision micro force sensor was selected,the micro force was amplified by using the lever and the friction resistance was reduced;the measurement resolution reached 0.003 3 mg/cm^(2).The results of comparison test between the system and the tracer method showed that the relative errors were 5.13% and 6.13% for measurements on the horizontal and vertical planes respectively,indicating that the system had good precision.Tests to research the influences of the temperature,the air velocities,the liquid evaporation and the pesticides species on measurement precision were conducted,and the results showed that the influences on the measurement precision by these factors were small and the system had good stability.The measurement system provided a method to measure droplet mass deposit promptly for spraying regulation research and had good practicability.