避险车道驶入角计算方法评价

Evaluation the Computing Method of the Entry Angle on Truck Escape Ramp

避险车道驶入角取值直接影响失控车辆能否安全驶入避险车道。基于车辆动力学仿真采用极限侧向加速度参数评价避险车道驶入角计算方法。首先,通过失控车辆稳定性分析确定车辆极限转弯半径;其次,采用三种驶入角的计算方法分别计算三种车速对应的避险车道驶入角;最后,基于车辆动力学仿真软件TruckSim,分别建立失控车辆和避险车道仿真模型,以极限侧向加速度作为评价指标设计并完成3组车辆稳定性仿真。仿真结果表明:方法二比方法三合理。对于方法二,进一步分析驶入角与主线转弯半径的关系,结果也表明方法二比方法三合理;继续采用极限侧向加速度作为评价指标并进行仿真,优化方法二的驶入角范围并与其它研究对比,结果表明了方法二优化结果的正确性。

The range of entry angle on truck escape ramp affects whether the runaway vehicle can enter the arrester bed safely. A modified limited lateral acceleration of vehicle was used to evaluate the computing method of entry angle on truck escape ramp by vehicle dynamics simulation in the paper. Firstly, the limited turning radius was determined based on the stability analysis of the runaway vehicle. Secondly, the entry angles were calculated respectively at three varied vehicle speeds under the same radius. Finally, vehicle model and ramp model were built using the TruckSim software, and three groups of vehicle stability simulation were designed and completed. Simulation results show that the second method is more reasonable than the third method. The analyzation of the relationship between the entry angle and the turning radius on the main road also show the same result. For the second method, we applied the same index to optimize the range of entry angle, which was compared with the other results and shows the optimized results are correct.