Adaptive human interface for refreshing sleep based on biological rhythm

The purpose of this research is to control human state and biological rhythm. The system has to be adaptive and intelligent because it must deal with human information including personal differences. As a first step to achieve the function, we try to estimate a human's state in sleep using a wearable sensor device, under less physical movement than daytime. In the next step, we try to control human biological rhythm using the method to estimate human sleep state. We consider the simplest way to control human's sleep is to control awakening timing and sleep time. The proposed system can estimate human sleep quality and rhythms, and provide stimuli based on wake up timing. The system uses only pulse wave to estimate sleep quality because the pulse wave can be measured more easily than PSG.