Immediate and Short-Term Benefits of Connected Fleet Deployments
As noted earlier, equipping vehicles with the 5.9 GHz DSRC technology to receive SPaT broadcasts and transmit BSMs is an entry-point into vehicle-to-infrastructure (V2I) deployment and operations under the Connected Fleet Challenge. The immediate and short-term benefits of deploying OBUs on fleet vehicles will largely be internal benefits to the agencies in the form of lessons learned and overall knowledge gained about deploying DSRC-based vehicle equipment (e.g. gaining experience with OBU and antenna installation, data and message generation, transmission, and processing, and operations), as well as opportunities to validate and leverage the exchange of information with deployed SPaT infrastructure. It is expected that the financial, safety, and mobility benefits of any V2I applications installed on the OBUs will come later, as agencies more widely deploy V2I applications on more vehicles and infrastructure. The intent of the Connected Fleet Challenge is to further advance practices and help agencies eventually reach higher benefit/cost ratios with regard to V2I deployments.
Long-Term Anticipated Benefits of Connected Vehicle Deployments
Ultimately, the mobility, safety, and efficiency benefits of vehicles equipped with OBUs to communicate with the infrastructure will be more realized as additional on-board applications are included and as the percentage of vehicles equipped with OBUs increases. Here are some examples of how connected fleets might leverage deployed SPaT infrastructure, and the anticipated benefits of these applications:
- Red Light Violation Warning (RLVW) Applications warn drivers approaching signalized intersections when the potential for running the red light is determined based on the SPaT data received from the infrastructure and the vehicle data (speed; distance to stop bar; braking status), creating the opportunity to reduce red light running related crashes.
- Signal Priority/Pre-emption Applications operating in areas with SPaT broadcast equipped intersections could be enhanced for Transit Signal Priority (TSP), Freight Signal Priority (FSP), and emergency vehicle pre-emption for example, enabling more sophisticated decisions regarding priority and pre-emption requests and ultimately reducing delay for all vehicles at these intersections. These applications might be leveraged using agency snow plow vehicles or in conjunction with other transportation partners, including transit agencies, first responders, or freight and delivery carriers.
- Intelligent Traffic Signal Systems (ISIG) Applications use high-fidelity data collected from vehicles and SPaT broadcasts from the infrastructure to control signals and optimize traffic flows in real time, serving to maximize overall network performance for reduced congestion and delay for all vehicles at SPaT-equipped intersections.
- Fleet Management Applications leverage communications with the roadside equipment to understand the current status of congestion in an area and determine how fleet vehicle operations may be impacted.
- Road Weather Management Applications use information received from equipped plow vehicles that collect and transmit road weather information in V2I messages, such as plow up or down, wiper status, grip information, surface temperature, air temperature, and relative humidity.
- Performance Management Applications monitor and respond to real-time congestion levels at intersections or along a corridor, as well as tracking traffic patterns over time.
- Eco-Approach and Departure at Signalized Intersections Applications present information to drivers about traffic signal timing, enabling drivers to adapt their speed so they pass through the intersection on green or decrease speed to a stop in the most eco-friendly way possible.
These are just a few examples of the types of additional applications that agencies, OEMs, or aftermarket providers could add to leverage OBUs at intersections that are equipped with SPaT functionality.