为了提高声表面波传感器应变灵敏度,该文提出了一种桥型声表面波应变传感器.首先根据受压弯曲构件中应变分布特点设计了桥型声表面波应变传感器,并建立有限元模型,结合微扰法分析了桥型结构几何参数与声表面波应变传感器灵敏度的关系.根据分析结果确定桥型声表面波应变传感器几何结构参数,并与传统声表面波应变传感器的应变灵敏度进行了对比研究,在此基础上搭建受压弯曲微动平台开展实验研究,结果表明:在直梁构件受压弯曲应变测量时,Y34?切向的桥型声表面波应变传感器的应变灵敏度为1692 Hz/με,传统声表面波传感器应变灵敏度为1328 Hz/με,桥型声表面波应变传感器的应变灵敏度较传统声表面波应变传感器有明显提高.
A SAW strain sensor with new simplified Epoxy-Quartz packaging is analyzed in this paper. The strain sensitivity of sensors with Epoxy-Quartz Package is calculated with perturbation theory and finite element method theoretically. The sensitivity is close to the sensitivities of traditional AQP, which are 3.20 ppm / με and 3.32 ppm / με respectively. Then an Epoxy-Quartz Packaged 433MHz SAW strain sensor is fabricated by using the epoxy EP-4 adhesive. An experimental platform is set up and the strain sensitivity of Epoxy-Quartz Packaged is measured at 20 °C. The experimental results indicate that strain sensitivity of Epoxy-Quartz Packaged is 2.51 ppm / με, which almost agrees with theoretical results. Therefore, a new simplified package for SAW strain sensor with a relatively high strain sensitivity is verified in this paper.
多通道动声系统(DMS)是基于声场优化原则与惠更斯原理开发的多通道拾音还音系统,系统录音部分采用近远场结合的相控传声器阵列拾音方法,重放部分根据声道特点有效地分配直达声和混响声。基于心理声学,以对比实验为整体思路,通过语义细分法对比DMS系统和立体声系统带来的听感上的区别,从而证明弱相关系统可以改善听音效果,为将来的系统发展从听觉心理学的角度指明了科研和发展方向。