One well-known class of surface haptic devices that we have called Tactile Pattern Displays (TPaDs) uses ultrasonic transverse vibrations of a touch surface to modulate fingertip friction. This article addresses the power consumption of glass TPaDs, which is an important consideration in the context of mobile touchscreens. In particular, based on existing ultrasonic friction reduction models, we consider how the mechanical properties (density and Young's modulus) and thickness of commonly-used glass formulations affect TPaD performance, namely the relation between its friction reduction ability and its real power consumption. Experiments performed with eight types of TPaDs and an electromechanical model for the fingertip-TPaD system indicate: 1) TPaD performance decreases as glass thickness increases; 2) TPaD performance increases as the Young's modulus and density of glass decrease; and 3) real power consumption of a TPaD decreases as the contact force increases. Proper applications of these results can lead to significant increases in TPaD performance.

中文翻译：

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玻璃的机械性能和厚度如何影响 TPaD 性能

一类众所周知的表面触觉设备，我们称之为触觉模式显示器 (TPaD)，它使用触摸表面的超声波横向振动来调节指尖摩擦。本文讨论了玻璃 TPaD 的功耗，这是移动触摸屏环境中的一个重要考虑因素。特别是，基于现有的超声减摩模型，我们考虑了常用玻璃配方的机械性能（密度和杨氏模量）和厚度如何影响 TPaD 性能，即其减摩能力与其实际功耗之间的关系。使用八种类型的 TPaD 和指尖-TPaD 系统的机电模型进行的实验表明：1) TPaD 性能随着玻璃厚度的增加而降低；2）TPaD性能随着玻璃杨氏模量和密度的降低而增加；3) TPaD 的实际功耗随着接触力的增加而降低。正确应用这些结果可以显着提高 TPaD 性能。