Speed Compliance

The NYC Vision Zero is focused on the reduction of crashes and pedestrian injuries within the city limits. One method recently adopted by NYCDOT was a reduction in the citywide speed limit from 30 mph to 25 mph based on the assumption that slower speeds would provide drivers with more time to react to traffic conditions and to avoid pedestrians and bicycles. Signals were retimed for the slower speed, and the City proposed to use CV technology to alert drivers when they are exceeding the speed limit. This becomes particularly important during late night when there is minimal traffic and speeds tend to far exceed the speed limit.

This application will use a regulatory speed limit in combination with the measured speed and location of the vehicle to provide warnings to the driver when they are exceeding the speed limit by a configurable amount or time. The warnings (alert) will be provided via an audio tone(s) and/or spoken warning which will be determined during the detailed design.

Some of the speed zones vary by time-of-day and day-of-week (e.g., school zones); hence, this information must include a schedule and the geographic boundaries of the speed zone. Note that the regulatory speed is not universal for all roadways; expressways within the City have higher speed limits and hence, the speed limit will depend on the vehicle location.

Since multiple safety applications will be running on the ASD at the same time, a configurable arbitration technique will be employed to ensure that the warning with the highest immediate threat is the warning presented to the driver. The arbitration algorithm will be configurable such that additional applications can be added to the ASD.

This application is intended to work with generally static roadway conditions or zones that are triggered due to the time-of-day and day-of-week. The source of the regulatory speed limit will be messages from the local RSE associated with the roadway map, curve location, or zones (work as well as school). These speeds will be delivered to the vehicle through DSRC MAP, TIM, Roadside Alert (RSA) or other messages.