Various studies have been conducted for developing interaction techniques in a smart house. Some of our previous studies [1, 2] focused on bathrooms and we converted an existing normal bathtub system into a user interface by using embedded sensors. A system called Bathcratch [2] detects squeak sounds by rubbing on a bathtub edge. To generate squeaks, it requires some conditions to cause the Stick-slip phenomenon. A bathtub has a smooth surface, and water can cause the phenomenon with human skins. Bathcratch uses it as an interaction technique to play DJ-scratching. Here, we extended the interaction technique using squeaks to recognize rubbing states, rubbing events including sequence, and the difference between squeaks caused by the number of fingers. This can be used in various wet environments including kitchen, washbowls in a restroom, swimming pool, and spa. This paper describes the method and its performance for identifying the number of rubbing fingers by using frequency analysis. In addition, we illustrate some smart home applications by using the proposed technique.
['Ryosuke Kawakatsu', 'Shigeyuki Hirai']
Interaction Technique Using Acoustic Sensing for Different Squeak Sounds Caused by Number of Rubbing Fingers