Virginia Tech, Mechanical Engineering, Blacksburg, VA 24060, USA.
Traffic Inj Prev. 2013;14 Suppl:S77-86. doi: 10.1080/15389588.2013.796374.
Safety impact methodologies (SIMs) have the goal of estimating safety benefits for proposed active safety systems. Because the precrash movements of vehicles involved in real-world crashes are often unknown, previous SIMs have taken the approach to reconstruct collisions from incomplete information sources, such as scaled scene diagrams and photographic evidence. The objective of this study is to introduce a novel methodology for reconstructing the precrash vehicle trajectories using data from advanced event data recorders (EDRs).
Some EDRs from model year 2009 and newer Ford vehicles can record steering wheel angle in addition to precrash vehicle speed, accelerator pedal, and throttle input prior to the crash. A model was constructed using these precrash records and a vehicle model developed in the simulation software PreScan. The model was validated using the yaw rate and longitudinal and lateral accelerations also recorded by this type of Ford EDR but not used to develop the models.
In general, the model was able to approximate the dynamics recorded on the EDR. The model did not match the observed dynamics when either the vehicle departed the paved surface or when electronic stability control was active. Modifying the surface friction at the estimated point at which the vehicle departed the road produced better simulation results. The developed trajectories were used to simulate 2 road departure crashes, one into a fixed object and one into a vehicle traveling in the opposite direction, as if the departing vehicle were equipped with a lane departure warning (LDW) system. This example application demonstrates the utility of this method and its potential application to a SIM.
This study demonstrated a novel method for crash reconstruction that can be applied to a SIM for active safety systems. Benefits of this method are that the driver inputs do not need to be inferred from other reconstructions because they are recorded directly by the EDR. Currently, there are too few cases with the advanced EDR data to estimate fleet-wide benefits of a system. Because of recent regulation (49 CFR Part 563), EDRs are likely to be downloaded in more real-world crashes, making this method a potentially valuable and low-cost method for developing SIMs in the future.
安全影响方法（SIMs）旨在估计拟议主动安全系统的安全效益。由于涉及实际事故的车辆的碰撞前运动通常是未知的，因此以前的 SIM 采用了从不完善的信息源（如比例场景图和照片证据）重建碰撞的方法。本研究的目的是引入一种使用高级事件数据记录器（EDR）数据重建碰撞前车辆轨迹的新方法。
一些 2009 年及以后型号的福特车辆的 EDR 除了在碰撞前记录车辆速度、油门踏板和节气门输入外，还可以记录转向盘角度。使用这些碰撞前记录和在仿真软件 PreScan 中开发的车辆模型构建了一个模型。使用这种类型的福特 EDR 记录的横摆率以及纵向和横向加速度验证了模型，但未用于开发模型。
一般来说，该模型能够近似记录在 EDR 上的动态。当车辆驶离路面或电子稳定控制系统激活时，该模型无法匹配观察到的动态。修改车辆驶离路面时估计的路面摩擦点会产生更好的仿真结果。开发的轨迹用于模拟 2 起道路偏离碰撞，一起进入固定物体，一起进入相反方向行驶的车辆，就像偏离车道的车辆配备了车道偏离警告（LDW）系统一样。该示例应用演示了该方法的实用性及其在主动安全系统 SIM 中的潜在应用。
本研究展示了一种新颖的碰撞重建方法，可应用于主动安全系统的 SIM。该方法的优点是，由于 EDR 直接记录，因此不需要从其他重建中推断驾驶员输入。目前，由于先进的 EDR 数据太少，无法估计系统在整个车队中的效益。由于最近的法规（49 CFR 第 563 部分），EDR 可能会在更多的实际事故中被下载，因此该方法是未来开发 SIM 的一种潜在有价值且低成本的方法。
