雨量计自动校验仪设计

Design of an automatic calibrator for pluviometer

雨量计是气象、水文、农业等部门观测降水量的重要仪器,新生产的雨量计以及使用中的雨量计都需要进行校验以确保其精度和可靠性.目前利用手工校验的方法不方便且精度难以保证,针对这一情况,设计了一种便携式雨量计自动校验仪.该仪器利用超声波实时检测当前液位进而控制步进电机自动调节流速、流量,保持水流量的均匀.利用软件可设置不同的雨量来模拟实际的降雨,最后通过对比雨量计读数看其是否符合精度要求.系统选用了高频的超声波传感器,处理器计时频率达到50MHz,提高了测量的精度.

Pluviometer is an important instrument for meteorological, hydrographic and agricultural departments to measure rainfall. Newly produced or in-service pluviometers are all need to be checked to guarantee the precision and reliability. Yet the manual checking method is not convenient and the checking soutits precision is hard to guarantee. For this reason, we designed a portable automatic calibrator for pluviometer. It uses ultrasonic to detect the liquid level and then controls the stepper motor to regulate velocity and flow automatically, thus keep the water flow evenly. Different rainfall can be set via the software to simulate the real rainfall. The measurement precision is calculated by comparison of the pluviometer readings with the software set values. To ensure the checking precision, we use high-frequency ultrasonic transducer and the timing frequency of CPU reaches 50 MHz. Experiment results show that the calibrator has high checking precision, and can preferably meet the requirements of the existing meteorologi- cal observation.