Multi-sensor Fusion Based on Asymmetric Decision Weighting for Robust Activity Recognition

The recognition of human activity has been deeply explored during the recent years. However, most proposed solutions are mainly devised to operate in ideal conditions, thus not addressing crucial real-world issues. One of the most prominent challenges refers to common sensor technological anomalies. Sensor faults and failures introduce variations in the measured sensor data with respect to the equivalent observations in ideal conditions. As a consequence, predefined recognition systems may potentially fail to identify actions in the anomalous sensor data. This paper presents a novel model devised to cope with the effects introduced by sensor technological anomalies. The model builds on the knowledge gained from multi-sensor configurations, through asymmetrically weighting the decisions provided at both activity and sensor levels. Insertion and rejection weighting metrics are particularly used to eventually yield a unique recognized activity. For the sake of comparison, the tolerance to sensor faults and failures of standard activity recognition systems and the new proposed model are evaluated. The results prove classic activity-aware systems to be incapable of recognition under the effects of sensor technological anomalies, while the proposed model demonstrates to be robust against both sensor faults and failures.