MultiSense: Cross-labelling and Learning Human Activities Using Multimodal Sensing Data

To tap into the gold mine of data generated by Internet of Things (IoT) devices with unprecedented volume and value, there is an urgent need to efficiently and accurately label raw sensor data. To this end, we explore and leverage the hidden connections among the multimodal data collected by various sensing devices and propose to let different modal data complement and learn from each other. But it is challenging to align and fuse multimodal data without knowing their perception (and thus the correct labels). In this work, we propose MultiSense, a paradigm for automatically mining potential perception, cross-labelling each modal data, and then updating the learning models for recognizing human activity to achieve higher accuracy or even recognize new activities. We design innovative solutions for segmenting, aligning, and fusing multimodal data from different sensors, as well as model updating mechanism. We implement our framework and conduct comprehensive evaluations on a rich set of data. Our results demonstrate that MultiSense significantly improves the data usability and the power of the learning models. With nine diverse activities performed by users, our framework automatically labels multimodal sensing data generated by five different sensing mechanisms (video, smart watch, smartphone, audio, and wireless-channel) with an average accuracy 98.5%. Furthermore, it enables models of some modalities to learn unknown activities from other modalities and greatly improves the activity recognition ability.