The Influence of the Centroid of Loaded Goods Under the Ice and Snow Road on the Handling Stability of Articulated Semi-trailer Truck

The tractor semi-trailer is prone to rollover, yaw instability and other hazards on ice and snow roads. In order to study the influence of centroid of goods position on the handling stability of the tractor semi-trailer, a tractor semi-trailer model is established in ADAMS/car, and a mathematical model of six degrees of freedom articulated semi-trailer truck dynamics is established based on the vehicle dynamics theory. It is stipulated that the centroid of the tractor semi-trailer with full load is the highest center of mass. According to the “Design Specification for Highway Alignment”, a straight road and a circular curve road with a radius of 70m are established, and the road adhesion coefficient is set to be 0.25. The vehicle drives at a constant speed of 30km/h, and the height of centroid begins to drop from the highest position. The simulation results show that whether it is a straight road or a circular curve road, the height of the center of mass will decrease. The upward movement of the goods' center of mass the has little influence on the lateral acceleration and yaw rate of the semi-trailer, but has a great influence on the rolling angle. In the circular curve road, the roll angle decreases by 0.14° when the mass center of the goods decreases by 0.3m. It shows that the upward movement of the centroid increases the possibility of the tractor semi-trailer rollover. Then, the centroid of goods is placed at the highest center of mass, and the uniform acceleration simulation is carried out on the circular curve road. The results show that when the vehicle speed increases to 38.2865km/h, the yaw rate of the semi-trailer decreases in a short time, and the vehicle leaves the road. It shows that when driving on ice and snow roads with low road adhesion coefficient, if the centroid of goods is at the highest position and the speed reaches 38.2865km/h, the tractor semi-trailer will have yaw instability and leave the road to cause traffic accidents.