In September of 2015, USDOT selected New York City Department of Transportation (NYCDOT), Wyoming Department of Transportation (WYDOT) and Tampa Hillsborough Expressway Authority (THEA) as the recipients of a combined $42 million in federal funding to pilot next-generation infrastructure and vehicle technology under the Connected Vehicle Pilot Deployment Program.
All of the connected vehicle applications being implemented and evaluated in the Connected Vehicle Pilot Deployment Program did not need to be developed from scratch. Software developers for the three CV Pilot sites have been able to take advantage of software prototyped by many programs, including the USDOT’s Dynamic Mobility Applications (DMA) program and the Safety Pilot Model Demonstration project in Ann Arbor, MI.
One of the THEA Pilot’s applications that required adaption was the Pedestrian Crossing (PED-X) application, originally planned to warn pedestrians crossing Twiggs Street of approaching vehicles that might be on a collision course. The mid-block pedestrian crossing connects the county courthouse and the nearest parking garage. The system design indicated that a Roadside Unit (RSU) will convert Basic Safety Messages (BSMs) broadcast by approaching vehicles to WiFi messages. Mobile devices (smartphones) carried by pedestrians would then receive these messages and compute the probability of a collision, based on the pedestrian’s current location and walking speed. However, the mobile device was unable determine the pedestrian’s location and speed with sufficient accuracy - for example to distinguish stepping into the street from standing on the sidewalk - to avoid numerous false alarms. Therefore, the PED-X application was configured to archive generated warnings to the device for future study and analysis, but did not issue any real-time warnings to pedestrians. The mobile devices were also configured to generate, save, and transmit via WiFi Personal Safety Messages (PSMs) similar to BSMs, but these PSMs were not be used to generate alarms to approaching vehicles.
The THEA solution will modify the vehicular side of PED-X to create the Pedestrian Collision Warning (PCW) application. Since the PSMs from mobile devices do not provide sufficient accuracy for reliable warnings, the PCW application will use pedestrian locations from two LIDAR sensors installed near the crosswalk. The LIDAR sensors will send pedestrian location information to the RSU via landline. The RSU will generate PSMs and broadcast them via Dedicated Short-Range Communication (DSRC) to the OBUs of approaching instrumented vehicles. Each instrumented vehicle’s OBU will determine whether a collision is possible, and if so will issue a warning to the vehicle’s driver.