User identification method in a bathtub with a water pressure sensor
Kazuya Murao, Sarina Nakayama, Masahiro Mochizuki, Nobuhiko Nishio · 2018
Along with the downsizing of computers and sensors, user situation and state can be recognized by sensing, signal processing, and machine learning technologies in many places. In home environments, it is reported that the number of drowned people in a bathtub has increased to 4,886 in 2004, which is 1.7 times from 2004. In order to prevent the occurrence of such a fatal accident, it is important to grasp the state of people while bathing. In this study, we propose a method to identify people in the bathtub from changes in water level during bathing with a water pressure sensor installed at the bottom of the bathtub. In the evaluation experiments, the average identification accuracy for four subjects is as low as 65% in the comparison method using only the change in the water level before and after entering the bathtub. The proposed methods uses DTW distance of the waveform of entering water section and exiting water section and its average accuracy achieved 95%.