Design and Implementation of a Novel Cost-effective Fall Detection and Intervention System for Independent Living Based on Wireless Sensor Network Technologies

Physical and cognitive decline associated with the natural aging process require the implementation of integrated and ambulant assistive technologies for the elderly to sustain independence with respect to Activities of Daily Living (ADLs). These technologies, framed in the context of Ambient Assisted Living (AAL), instantiate environments where sensor modules and robotic agents mitigate and/or compensate for the declining dexterity and diminishing strength of the occupants. Research trends in this field suggest the importance of such assistive services, especially considering that all emerging industrial nations are experiencing aging-related demographic change. In this paper the authors propose the design and implementation of a low cost, ad hoc Wireless Sensor Network (WSN) system that integrates seamlessly into a WiFi-dependent mobile rover (i.e., TurtleBot) system, effectively creating a versatile yet robust de facto Cyber-Physical Network (CPN) where gathered WSN sense-data is used to trigger events in the rover. The system will first be outlined, followed by a detailing of a concrete use-case example, where a laser emitted from one WSN module to a series of photosensitive sensors in another is used to detect the presence and location of unexpected objects (e.g., collapsed person and/or furniture etc.); and where the rover is instructed to autonomously navigate to this location to further ascertain the status of said object(s). The example intends to illustrate the potential of a multi-layered, energy-efficient, self-configurable, scalable and reliable sensing-actuating system that can be added to existing WiFi networks without technical difficulty or network modifications.