A Real-time Ubiquitous System: Real-Time Indoor Tracking of Humans and Objects for Assisted Living

As the elderly population increases, the elderly care using inexpensive technological means becomes critical. This paper presents our prototype system that provides real-time indoor tracking of elderly residents and their belongings, which is essential to assist and secure their independent living. For high-fidelity real-time tracking, we propose novel scheduling algorithms. Our scheduling algorithms are designed by harmonizing both sensing and communication signals and leveraging location-awareness and mobility-consciousness, in order to improve the tracking accuracy while reducing the energy consumption. We performed extensive experiments through both simulation and actual implementation. Our experimental result says that our scheduling algorithms can provide real-time tracking of residents within 20 cm error bound in the typical range of human mobility. ∗This work was supported in part by NSF-CSR 0509175 and in part by Research Settlement Fund for the new faculty of SNU. A part of this work has been done when the authors were in OSU. A preliminary version of this paper has appeared in the proceedings of IEEE Real-Time Systems Symposium (RTSS), 2006. The corresponding author is Chang-Gun Lee.