Fine-Grained Activity Recognition by Aggregating Abstract Object Usage Donald J. Patterson, Dieter Fox, Henry Kautz Matthai Philipose University of Washington Intel Research Seattle Department of Computer Science and Engineering Seattle, Washington, USA Seattle, Washington, USA
[email protected] {djp3,fox,kautz}@cs.washington.edu Abstract in directly sensed experience. More recent work on plan- based behavior recognition [4] uses more robust probabilis- In this paper we present results related to achieving fine- tic inference algorithms, but still does not directly connect grained activity recognition for context-aware computing to sensor data. applications. We examine the advantages and challenges In the computer vision community there is much work of reasoning with globally unique object instances detected on behavior recognition using probabilistic models, but it by an RFID glove. We present a sequence of increasingly usually focuses on recognizing simple low-level behaviors powerful probabilistic graphical models for activity recog- in controlled environments [9]. Recognizing complex, high- nition. We show the advantages of adding additional com- level activities using machine vision has only been achieved plexity and conclude with a model that can reason tractably by carefully engineering domain-specific solutions, such as about aggregated object instances and gracefully general- for hand-washing [13] or operating a home medical appli- izes from object instances to their classes by using abstrac- ance [17]. tion smoothing. We apply these models to data collected There has been much recent work in the wearable com- from a morning household routine. puting community, which, like this paper, quantifies the value of various sensing modalities and inference tech- niques for interpreting context.