Applications for the Environment: Real-Time Information Synthesis (AERIS) program
Nationwide, United States
ECO-ITS: Intelligent Transportation System Applications to Improve Environmental Performance
Summary Information
With recent advances in ITS technology it is now possible for traffic signal control systems to communicate directly to in-vehicle intelligent speed controls to help drivers smooth acceleration and deceleration profiles and adjust cruise speeds between intersections. As part of this project, researchers developed an eco-driving velocity planning algorithm to help drivers minimize fuel consumption and reduce emissions on arterial corridors.
Using a simulation model, the system impacts were evaluated on a representative arterial route with 10 signalized intersections and low density traffic. Overall, the eco-driving system was designed to maintain several parameters including steady state speeds at or near the speed limit, safe headway distances, strict observation of red lights, minimized idling times at traffic signals, and an aversion to sharp changes in speed. Performance data were simulated for a variety of corridor operating scenarios with and without eco-driving for similar types of vehicles (mid-sized sedan).
Preliminary results indicated that the eco-driving velocity planning algorithm improved fuel economy 10 to 15 percent compared to the baseline case without the system.
Researchers found that velocity profiles that used hard acceleration to quickly move vehicles to target cruising speeds were more fuel efficient than profiles that used lesser acceleration but higher speeds to reach the same point at the same time. Similarly, it was beneficial to decelerate more quickly and then hold a steady state cruise speed to reach a traffic signal just in time for green and minimize the energy needed to re-accelerate to free flow speeds.
