Study on high efficiency and large mechanical output surface acoustic wave actuator

我们发现在能量循环驱动SAW电机IDT中，几十度的相移会导致循环能量的下降。为此，我们改进了IDT的仿真等效电路模型，并研究了IDT的分配方法。因此，我们决定改变激振IDT的布置方式，将两个驱动IDT分别布置在靠近两端循环单向IDT的位置。为此，需要精确的建模参数来拟合实际设备。在滑块下方传播的瑞利波被滑块表面的投影散射。采用有限元法对这种现象进行了模拟。由于滑块与定子的接触和脱离引起二次波源的投影，使滑块表面平整，将有效地减少散射。为此，应考虑设计平面滑块，以减少挤压膜。

We have found that several tens degrees of phase shift in an energy circulation drive SAW motor IDT will cause decrease of the circulation energy. So that we improve an simulation equivalent circuit model for IDT and investigated the IDT allocation method. As a result, we decided to change the arrangement of exciation IDT, two driving IDTs were separately arranged at near both end circulation uni-directional IDTs. For this purpose, precise modeling parameters are required to fit the actual device.The Rayleigh wave propagating beneath the slider is scattered by the projections on the slider surface. This phenomenon was simulated by using the FEM analysis. Due to the contact and take off of the slider projection from the stator causes the secondary wave source, so that a flat slider surface will be effective to reduce the scattering. For this, a flat surface slider with some design to reduce the squeeze film should be considered.