Indoor-outdoor activity recognition by a smartphone

Abstract

It is increasingly important to recognize daily activity pattern in order to detect early sign of dementia in the aging society. This paper shows indoor-outdoor activity recognition using only a smartphone. We developed an indoor living activity recognition engine and an outdoor migration activity recognition engine, and combined them into an Android™ application. The former recognizes not only "resting" or "walking" but also user's various living activities such as "vacuuming" and "brushing teeth" by using a built-in accelerometer and a built-in microphone. The latter engine recognizes the user's means of migration, namely, "resting," "walking," "running," and "boarding" by using a built-in accelerometer. It enables users to continuously recognize indoor-outdoor activities by switching between the two engines depending on an acquisition condition of GPS.