Measurement system of swallowing motion by using a piezoelectric film sensor

In this paper, a measurement system of swallowing motion is developed. A piezoelectric film is used as sensitive material of the sensor to measure the body surface deformation due to swallowing. We focused on laryngeal prominence and digastric muscle which are active during swallowing and developed sensors to attach to skin above laryngeal prominence and digastric muscle. As a result of experiments, it was confirmed that output fluctuation occurred at the swallowing. Next, by comparing the frequency spectral density distribution of sensor outputs during swallowing and resting, it was found that the output waveform during swallowing is mainly composed of larger frequency components below 20 [Hz] than that during resting. From the results, it was suggested that the developed measurement system is available to detect the swallowing from skin deformation without obstructing the motion.