| Road traffic system is a driver, vehicle, road and environment of complex dynamic systems. The function of any of these factors which can not be effectively or failure of collaboration between the different factors can lead to traffic accidents. The drivers who obtain, process information and complete the driving operation, is the most important component of the road traffic system. Therefore, the study of the participants in the road, especially in the driver's driving behavior has the great significance for the prevention of road traffic accidents.Driver fatigue is the common form of bad driving behavior, and is one of the most important factors of traffic accidents. The factors that affect driver fatigue are complex, and previous studies often focus on the internal factors such as the driver menstrual cycles, sleep time to start. In fact, driver fatigue is formed by the inside and outside factors together. Driver fatigue, not only is associated with the state of drivers before driving, but also depends on driving period, road environment and other external factors in driving. As Nelson said,"Fatigue is not only certain substances in the brain, but also is heavily influenced by your personality, what and where you are doing."In this paper, the effect of road environment monotony on driving fatigue is chosen as the key of study, and the relationship both is given using driving simulator. The driver psychological and driver performance indicators are analysis and driver fatigue detection indicator is estimated. Road environment evaluation based MPEG compression technique is proposed. The effect model of road environment monotony on driver fatigue is establishment, and the road environment monotony evaluation criterion is determined which can identify the risk associated with monotony sections and the degree of hazard by analyzing the driver's perception of the characteristics of the road scene. Details are as follows:Firstly, the theoretical analysis is given. It is clear that the core issue is how to accurately describe the impact of road environment monotony on driving fatigue by the mathematical methods. The four key sub-issues were given: the definition of driver fatigue, driver fatigue evaluation indicator estimated the road environment monotony analysis and the impact process of road environment monotony on driving fatigue. The definition of driver fatigue was proposed and the alternative indicators of driver fatigue evaluation were selected. The feasibility of road environment monotony detection based on MPEG compression technique was analyzed, and the theoretical model of the effects of road environment monotony on driving fatigue was given.Secondly, experimental system analysis was given. According to the requirements in this study, combined with driving simulation laboratory for the experimental devices, the experimental system platform was developed to meet the human, vehicle, road, environmental modeling and to accommodate the micro-driving and driving characteristics. Experimental platform design ideas, implementation plan and the platform analysis were described. The effectiveness of driving simulator to study driving behavior was verified. The result shows that the way of driving simulator is feasible to the research related to driver perception.Thirdly, the driving fatigue evaluation indictor was determined. EEG, ECG, eye movements and steering wheel and other indicators are determined as an alternative indicator system. In monotony environment, the variations of all indicators are analysis with driving duration. The stepwise regression model of steering wheel and physiological indicators is established. Considering the possible problems of driver fatigue detection indicators, a Person correlation coefficient analysis is used to determine the heart rate (HR) as the driving fatigue evaluation indicator.Fourthly, establish the road environment monotony evaluation based on MPEG compression technique. The feasibility of this method and such as sampling frequency, sampling rate and sequence length of compression parameters are evaluated. Considering different environment concern on different region and the most meaning information distribution, the different weight is distributed to different region with Victor's region division. And the calculation method of road environment monotony and stimulation point identification is proposed.Again, the effect mechanism of road environment monotony on driving fatigue was analyzed. The stimulate density in various scenarios as the monotony level is calculated using the evaluation method of the above part. The heart rate variation with driving duration is analysis, and the relationship curve between heart rate decreasing and driving duration is established based on different stimulation density. The threshold of road environment monotony evaluation is determined.Finally, the project applications are proposed. It is suggested that driving status is adjusted after 20 min continuous driving to maintain the normal level of alertness. In the design speed of 60 km/h, the circular curve radius after the long straight line with the driver psychological characteristics is 250m. According to the relationship between road environment monotony and driver fatigue, the stimulation interval is up to 5min. The driving difficulty is introduced to evaluate the driving workload. A circular curve as an example, the correspondence relationship between load degree and circular curve radius is given.The main content of this paper is to study the effect mechanism of road environment monotony on driving fatigue and put forward relevant countermeasures from the driving fatigue external factors. The results of the study related to driver fatigue can be incorporated into the overall control strategies of driving fatigue, and provide technical support for road planning and construction, road landscape design and transport management, thereby reduce fatigue-related driving accidents, improve road safety.
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