Analysis On Functional Connectivity Of Driver's Pedal Misapplication Based On Near-infrared Spectroscopy

In recent years,with the increase of car ownership,the proportion of young drivers rise,so road traffic safety has become the focus of public concern.One of the most key problem among young drivers is mistakenly stepped on the pedal,and It is often seen on television media that the driver mistakenly stepped on the accelerator pedal due to the emergency situation of tension and fatigue and other factors.This is fatal to the car driver or people outside of the car.In the drivers who more prone mistakenly stepped on the pedal,the possibility of error in the process of daily driving is much higher than not prone to error on operating population,brain regional coordination between people prone to mistake and normal people are different.Therefore,the purpose of this paper is to find out the physiological mechanism of the brain connection by the method of brain functional connectivity,and to provide the theoretical basis for the prevention of pedal misapplication on the design of the cab and the training of the students who apply for driving license.Brain functional connectivity is the main method to find the connection of pedal misapplication on the operating mechanism of the brain,it can reflect the correlation between the different regions of the neural activity of the brain,there is some connection between the characteristics of the low frequency of spontaneous nerve signals.Because of the neurovascular coupling,the neural activity and brain oxygenation has a certain correlation,so by detecting the oxygen concentration,the neural activity can be well reflected.This article acquiesces brain blood oxygen signals of different regions by a multi-channel near infrared spectroscopy system,the advantages of the near-infrared method is noninvasive,continuous,real-time detection of brain microcirculation.After pretreatment,wavelet transform was used to obtain specific characteristic frequency,then we can get wavelet phase coherence by calculating values between different channels,it was defined as an evaluation index of brain function.Wavelet phase coherence can be divided into six frequency bands according to the effects of different physiological sources:?,0.6-2.0 Hz;?,0.145-0.6 Hz;?,0.052-0.145 Hz;?,0.021-0.052 Hz;?,0.0095-0.021 Hz;?,0.005-0.0095 Hz.In this paper,the effectiveness of the simulated driving load is verified by the vigilance task model,and the brain oxygen concentration signal is measured simultaneously by simulating the normal driving and the task driving with the addition of the sudden factors and fatigue factors.Wavelet phase coherence of different channels is obtained by the Morlet wavelet transform to evaluate significant difference of the brain function connection in the normal driving.In summary,this paper shows that the interested frequency components can be extracted by wavelet transformed time-frequency domain.The effect of each frequency component(physiological source)on phase synchronization is determined.This paper explains the fundamental reason why drivers mistakenly step the wrong pedal,and provide a new perspective on the evaluation of driving level.