Automobile accidents are an ongoing epidemic in the United States. Pedestrian death rates and total automobile-related death rates have increased in recent years. Autonomous cars are the most anticipated solution to this problem; however, it will take a long time until all vehicles on the street are autonomous. I propose a secondary solution: to build a portable warning system (PWS) for pedestrians to reduce car crashes. My research project is to test whether it is feasible to build such a device using today's latest technology.