应变片用于斯特林发动机活塞位移的动态测量
Displacement Measurement of Free-Piston Stirling Engine Based on Strain Gauge

结合自由活塞斯特林发动机的结构特点，提出了采用应变片响应板弹簧变形来动态测量活塞位移的方法。根据应变片的电阻应变效应与应变仪的电桥原理，建立了一套应变片测量位移的动态标定试验系统，将动态标定数据与静态标定数据进行了比较分析。试验结果表明，应变片测量位移的方法存在一定的正反向、动静态差异，应变片的粘贴位置也会直接影响测量准确性。基于应变片传感器体积小，与板弹簧结合粘贴需占用专门的空间，通过标定校准和合理的安装位置，仍然是一种较好的位移测量传感器。
Combining the structure characteristics of free-piston Stirling engine, a kind of dynamic displacement measurement that the strain gauge are used to measure indirectly the displacement of displacer and piston by responding to shape change of plate spring is put forward. On the basis of strain-resistance effect and bridge principle of strain indicator, a set of dynamic displacement measurement system based on strain gauge is built up, and experimental data are compared with the data gotten from static displacement measurement. The experimental testing results indicate the data from dynamic displacement measurement are not exactly the same as the data from static displacement measurement, and the attaching position of strain gauge directly affected the accuracy of measurement.