Robust Human Activity Recognition Using Generative Adversarial Imputation Networks

Human activity recognition (HAR) is widely used in applications ranging from activity tracking to rehabilitation of patients. HAR classifiers are typically trained with data collected from a known set of users while assuming that all the sensors needed for activity recognition are working perfectly and there are no missing samples. However, real-world usage of the HAR classifier may encounter missing data samples due to user error, device error, or battery limitations. The missing samples, in turn, lead to a significant reduction in accuracy. To address this limitation, we propose an adaptive method that either uses low-power mean imputation or generative adversarial imputation networks (GAIN) to recover the missing data samples before classifying the activities. Experiments on a public HAR dataset with 22 users show that the proposed robust HAR classifier achieves 94% classification accuracy with as much as 20% missing samples from the sensors with 390 μJ energy consumption per imputation.