Effect of Deformation of Sensors Caused by External Forces on Precision of Detecting Driver's Vital Signs

Abstract

In order to prevent fatal traffic accidents triggered by sudden loss of consciousness of drivers, a non-contact brain wave sensor installed on the head restraint is studied. A textile microstrip patch antenna is fabricated and attached on the head restraint, then effects of its deformation due to the contact force between the head and the restraint are studied. Microwave is radiated through the antenna and reflected signal is measured by a spectrum analyzer and a return loss bridge. Visual evoked potential (VEP) is used to evaluate the effect of the deformation in the study; a checkerboard pattern flickering at 20Hz is imposed on a subject and the neuronal activities are measured by both conventional EEG and proposed sensor. Frequency response with peaks at 20Hz and 40Hz are observed by both methods. A numerical model is also used to perform electromagnetic analysis to study the response of brain tissue activated by the VEP.