Localization of tactile interactions through TDOA analysis: Geometric vs. inversion-based method

In this paper we propose an comparison of three different methods for the localization of tactile interactions with a planar surface, all based on the analysis of differences between time of arrivals from a single source to a set of contact sensors, located around the area of interest. We tested these methods with both synthetic and real data, taken recording a finger touch with four sensors placed over a MDF (Medium Density Fiberboard) board, to prove their accuracy and robustness against time delay estimation errors. The aim is to create tangible interfaces without intrusive sensors or devices placed inside the interaction area.