Beyond indoor presence monitoring with simple sensors

To have buildings that are able to adapt to the user needs and at the same time to operate efficiently, it is essential to know the activity the people are performing. Presence sensors, which are widely deployed in modern buildings, attempt to regulate lighting to the presence of people in indoor spaces. Though, much more in terms of comfort and energy efficiency can be achieved if more detailed information on the activity of the users is detected. In this paper, we provide an initial investigation on detecting indoor activities by using simple sensors (infrared, pressure and acoustic) deliberately avoiding the use of rich sensors such as cameras. The sensors are low-cost, wireless, and retrofittable in existing structures. Our prototype is able to recognize five activities (working at a desk with or without a PC, having a meeting, and the presence/absence in the office) with accuracy of almost 95%, while unaffecting user's behavior and comfort.