一种虚拟光照强度测试仪系统设计

Design of virtual light intensity tester system

在传感器课程实践教学中引入Proteus虚拟仿真软件辅助实验教学,设计了一种光照强度测试仪系统。该系统基于光敏电阻在不同光照射下具有不同阻值的特性,通过采集光信号、A/D转换、单片机处理,最终用数码管显示光照强度。为解决硫化镉光敏电阻的非线性特性问题,将光敏电阻特性曲线划分为光照较弱、光照适中和光照较强等3组小线段,而将小线段近似看作线性曲线以减少误差。将曲线划分为5组误差会更小。

Experiment box has been demonstrated in the traditional praetieal teaching of Sensor course, which eauses the lack of establishing hardware circuit and training code programming for students, Proteus virtual simulation software has been introduced into experiment teaching. This paper designs a virtual light tester system, students can master the hardware components and exercise code programming ability, by establishing hardware circuit in the Proteus environment, and programming in the Keil uVision environment. In view of the different resistance for photosensitive resistance in the different light eonditions, the light intensity value can be displayed on the digital tube by the processing of collecting light signal, AD conversion and single-chip microcomputer operation. In addition, due to the nonlinear resistance eharacteristics of cadmium sulfide photosensitive resistance, the line is divided into three groups, namely the weak light, moderate light and strong light illumination, in order to reduce error, the small segments can be approximately seen as linear curve features, at the same time, the error of five groups is smaller than that of three groups.