基于PIC18F4580的粮食称重系统设计  

Grain weight system design based on PIC18F4580

作　　者：周鹏[1] 王启增 毛文华[1] 赵博[1] 

机构地区：[1]中国农业机械化科学研究院土壤植物机器系统技术国家重点实验室,北京100083 [2]黑龙江省前锋农场,黑龙江佳木斯156325

出　　处：《电子设计工程》2011年第12期175-177,180,共4页Electronic Design Engineering

基　　金：国家科技支撑计划(2008BADA8B04-1)

摘　　要：在粮食品质检测分级过程中,为了测量样品的含杂率和容积密度,设计了一种高精度称重系统。以PIC18F4580为主控单元,采用四臂电桥式负荷传感器,用AD7799进行模数转换及传感器微弱信号的放大。差动式输入参考电压减小电源低频漂移时带来的系统误差。实际测试表明,系统测量重复误差不超过0.005%,系统非线性度误差小于0.007%,可以满足粮食检测过程的需求。A design of a precision weight system for testing percentage of impurities and bulk density in grain quality grading process is presented.This circuit used PIC18F4580 for signal processing,AD7799 for andlog-digital conversion and signal amplification,differential reference voltage input for decreasing the system low frequency drifting.Experimental results show that the repeatability error is less than 0.005% and the nonlinearity is less than 0.01%,which achives high precision and stablity requirement during the testing procedure.

关 键 词：PIC18F4580 AD7799 称重 负荷传感器 

分 类 号：TP271.5[自动化与计算机技术—检测技术与自动化装置]