Effect of frictional sound of combat uniform fabrics on Autonomic Nervous System (ANS) responses

The objectives of this study were to investigate the effect of frictional sound of Korean combat uniform fabrics on the human responses of ANS and to relate them to the mechanical properties of fabrics in order to find out the way to reduce frictional sound of combat uniform fabrics. Three different frictional sounds of combat uniform fabrics were selected by cluster analysis and their sound characteristics were calculated using Sound Quality System. Ten participants' ANS responses such as heart rate (HR), the ratio of LF/HF, skin conductance level (SCL), and pulse volume (PV) were measured during presenting the frictional sound as stimuli. Mechanical properties were measured by KES-FB system. Response differences (ANS responses after stimuli - those before stimuli) of HR and LF/HF significantly were positive to all of the fabric sounds, while the differences of pulse volume (PV) were negative. This phenomenon explains that sympathetic nerve system of all participants stimulated and they might feel nervous or bad with the frictional sound of fabric. WC, MMD, SMD and weight of fabric were negatively correlated with ANS, but RT, B and RC were positively correlated. They appeared to be influential factors affecting ANS responses.