A study on a method of robust swallowing detection to motion artifact

In the previous study, the possibility of swallowing detection was presented by using a wearable sensor embedded accelerometer. The swallowing detection was difficult when the elderly people in need of care swallowed with tremulousness as the motion artifacts. In this study, we use two accelerometers to reduce this motion artifacts, and detect clearly. Both the accelerometers were embedded an apron. Subjects kept holding a water in theirs mouth in sitting position, and were shaking their head back and forth, and swallowed after a call by the examiner. A differential signal was obtained from the two scalar values of the accelerometers. The motion artifact in the differential signal was largely reduced, and the swallowing signal was clearly obtained. A time integral value per unit of the acceleration signal（iAcc）was calculated. The iAcc of the swallowing phase was significantly greater than the iAcc of resting phase.