Robert T. Lynch, PE, Sr. Collision Reconstruction Engineer ::::
On average, a pedestrian is killed every two hours and injured every 7 minutes in traffic crashes in the United States with an overwhelming proportion of fatal collisions occurring at night . When corrected for mileage, nighttime fatality rates in the United States average more than three times greater than daytime rates. Under dark conditions, drivers rely on artificial lighting, such as from street lights and vehicle headlights, to illuminate their path in order to identify potential hazards. Not all roadways have street lights, and with the limitations of most vehicle headlight systems, drivers often “overdrive their headlights” where, at speeds as low as 35 miles per hour, a driver may be faced with an emergency where he or she cannot perceive, react and avoid the impending collision.
Recent advances in technology, mainly due to the rapid development of autonomous vehicles, include infrared sensors installed at the front of the vehicle to detect pedestrians and animals at night from a greater distance than headlights alone would allow the driver to observe. Therefore, even though a hazard may not be perceived visually by the driver, the potential exists for a quicker response via an audible warning signal stemming from the infrared sensor detection. BMW, through its supplier Autoliv, has developed a “Dynamic Spot Light” that directs a beam of light at a pedestrian or animal on or near the roadway. The warning tone, or visual cue, can lead to a more rapid response to a pedestrian at night while an increased recognition distance would allow more time and distance for a driver to respond, effectively decreasing the number of nighttime pedestrian impacts, or at least mitigating impact severity. We can expect to start to see this technology more prevalent in all vehicles (not just autonomous vehicles) sold in the United States in the coming years.
Robert T. Lynch, PE, is a Sr. Collision Reconstruction Engineer with DJS Associates and can be reached via email at experts@forensicDJS.com or via phone at 215-659-2010.
1 Traffic Safety Facts: Pedestrians, April 2014, National Highway Traffic Safety Administration (NHTSA).Categories: Collision / Accident Reconstruction | Pedestrian Safety | Robert T. Lynch