RF hand gesture sensor for monitoring of cigarette smoking

Today, over a billion people in the world are smokers. Smoking is associated with increased risk of cardiovascular disease, chronic obstructive pulmonary disease, emphysema, and various cancers, causing approximately 6 million premature deaths per year. Current methods of assessing smoking behavior (e.g., self-report, portable puff-topography instruments) do not permit the collection of accurate, non-reactive measures that capture real-time smoking frequency and comprehensive within-cigarette puff topography. Our goal is development of a noninvasive wearable sensor system (Personal Automatic Cigarette Tracker - PACT) that is completely transparent to the end user and does not require any conscience effort to achieve reliable monitoring of smoking behavior in free living individuals. A key component of PACT is a sensor that captures a characteristic hand-to-mouth gesture preceding cigarette smoke inhalations. This paper details design and validation of a wearable radio-frequency proximity sensor that measures the distance between an individual's wrist and chest in real-time. Hand-to-mouth gestures detected with this device provide quantitative data that can be used for analysis of behavioral patterns during smoking and other activities.