Non-invasive measurement and subsequent analysis of human carotid pulse for ground based simulation of G-stress

Gravitational G stress can debilitate pilots of modern fighter aircraft which may result in mishaps due to G-induced loss of consciousness G-LOC.The ability to bear G exposure is mainly a role of sufficient blood flow to the brain - the most susceptible and critical organ regarding aircrew performance. Carotid artery is the closest vessel to the heart and brain and is responsible for the blood flow between them. Past studies of high acceleration effects on physiological parameters has concluded that the heart rate variability HRV is the only parameter which can be effectively captured, stored, processed and analysed. Carotid pulse is an important signal to assess HRV. A simple and non-invasive system is developed in which piezoelectric sensor is placed on the carotid artery of the human subject. Raw carotid signal of many human subjects in real time is acquired in different body postures using BIOPAC system. RR interval, heart rate and pulse amplitude are determined using BIOPAC system software. The present work relates the effect of change in heart rate in different body postures to the change in heart rate due to G stress which further can be used for measurement and management of G stress of aircraft pilots.