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To analyze the effect of crosswind on the handling stability of tractor semi-trailers in double-lane change situations, the tractor semi-trailer model and the relative aerodynamic coefficient model were built by using TruckSim. Considering the factors of different crosswind directions, crosswind speed, and vehicle speed, we analyzed the relationship between these factors and the handling stability of tractor semi-trailers in double-lane change situations. The results show that a trailer has movement delay and worse handling stability compared to a tractor. The tractor/semi-trailer is unstable when the vehicle speed is 75 km/h and the crosswind speed is 40km/h or 60km/h. The tractor semi-trailer is stable when the vehicle speed is 70 km/h and the crosswind speed is less than 60km/h.

To analyze the influence of trailer length on passing ability of double semi-trailer road train (B-Train), we built B-Train model by using TruckSim, and confirmed limit steering wheel angle when all wheels of B-Train moved forward and the turning radius was minimum simultaneously by choosing dry pavement. And then, the turning process was simulated to analyze the relationship between the trailer length and the turning channel width at low speed. The results show that increasing trailer length leads to the increase of the turning channel width of B-Train; the turning channel width is larger when the length of the first trailer is increased independently than that when the length of the second trailer is increased independently. In addition, according to the simulation results, we built the relation model between trailer length variation and turning channel width using least-square theory.

Based on the theory and research methods of binocular vision, mechanical structure design and human-machine engineering, the portable investigation system in traffic accident scenes is designed and established. This system is composed of two ordinary fixed focus cameras, control and display unit, connection platform and other accessories, which is convenient(scale-free), accurate and portable for quick investigation of traffic accident scenes.

By taking Visual C++ and OpenCV as tools and processing video image sequences gathered by one camera under low view angle, suitable foreground detection method of intersection was selected. Through improving blob tracking system provided by OpenCV, the program was developed to detect motion parameters of vehicles in intersection. The motion parameters were smoothed by Kalman filter. It made the data more reliably. The research could be applied in detections of the traffic conflict and traffic information.

Parameters calibration constitutes the base of car following simulation by Desired Safety Margin(short for DSM model) . In the paper, the DSM model is introduced firstly. Then, the calibration method of the key parameters, including desired safety margin, acceleration and deceleration sensitivities, is proposed. Subsequently, based on driving performances of eight different drivers, with the statistical calculation and analysis, the calibrated parameters, upper and lower limits of desired safety margin, acceleration and deceleration sensitivities, are obtained. After that, with the calibrated DSM model, the application and simulation of a practical car following case are showed. Finally, the main research results are concluded.