Prof. Dr. Patrick Baudisch

Touch using Time Domain Reflectometry

Time domain reflectometry, a technique originally used in diagnosing cable faults, can also locate where a cable is being touched. We explore how to extend time domain reflectometry in order to touch-enable thin, modular, and deformable surfaces and devices. We demonstrate how to use this approach to make smart clothing and to rapid prototype touch sensitive objects of arbitrary shape. To accomplish this, we extend time domain reflectometry in three ways: (1) Thin: We demonstrate how to run time domain reflectometry on a single wire. This allows us to touch-enable thin metal objects, such as guitar strings. (2) Modularity: We present a two-pin connector system that allows users to daisy chain touch-sensitive segments. We illustrate these enhancements with 13 prototypes and a series of performance measurements. (3) Deformability: We create deformable touch devices by mounting stretchable wire patterns onto elastic tape and meshes. The paper also contaisn selected performance measurements.



Wimmer, R., and Baudisch, P. Modular and Deformable Touch-Sensitive Surfaces Based on Time Domain Reflectometry. In Proceedings of UIST 2011, pp. 517-526. NOMINATED FOR UIST 2011 BEST PAPER AWARD  PDF (3.0M)slides(ppt)