一种利用计算机技术在惠斯通电桥中精准测量电阻的方案

A scheme for accurate measuring resistance with Wheatstone bridge using computer technology

惠斯通电桥测量中值电阻是大学物理实验室基本实验,传统的测量方法存在测量精度低、数据处理费时费力等缺陷,基于单片机的方法虽有改进,但在测量精度及数据处理方面仍有不足。研究了一种利用计算机技术的惠斯通电桥测量电阻方案,该方案由计算机、测量软件、嵌入式处理器、电桥电路、高精度数控电阻箱组成,利用嵌入式处理器模块实现上下位机实时通讯,计算机控制下位机电桥电路调节平衡并采集电桥平衡时的测量数据,实现计算机自动采集测量数据,完成数据处理及存储。该方案使电阻测量更简单快捷方便,数据处理更直观科学精确,有利于教学活动的开展。

As a basic experiment, Wheatstone bridge is used to measure median resistance in university physics laboratory.Traditional measuring method has some shortcomings, such as low measurement accuracy, time-consuming and laborious data processing. Although the method has been improved by using single-chip computer, there are still some shortcomings in measurement accuracy and data processing. A new scheme using computer technology for measuring resistance with Wheatstone bridge is proposed in the paper, which is composed of PC, measuring software, embedded processor, bridge circuit and high precision NC resistance box. In the scheme, real-time communication between upper and lower computer is realized by using embedded processor module, and controlled by PC, lower computer can adjust electric bridge circuit to keep balance and collect the measurement data and repeat the process automatically, and complete the data processing and storage. This scheme makes resistance measurement more simple, convenient and faster, data processing more intuitive, scientific and accurate, and is conducive to implementation of teaching activities.