Eco-Driving of Freight Vehicles With Signal Priority on Congested Arterial Roads

This paper investigates a cooperative optimization framework of eco-driving and signal priority for freight vehicles in signalized arterial road. Considering the congestion of passenger vehicles at the signalized intersections, the problem is modeled as a multi-stage mixed integer optimization problem containing continuous variables (speed trajectory) and discrete ones (signal timing). The optimal speed trajectory is obtained with the objective of minimizing the fuel consumption of freight vehicles. Meanwhile, freight-priority optimal signal timing is achieved by minimizing the queueing delay of passenger vehicles at the intersections, while ensuring freight vehicles to avoid stopping and idling. The cooperative optimization problem is non-convex due to constraints from the queues and traffic signals in the network; therefore, a sub-optimal strategy restoring convexity is proposed to solve the problem. Comparison studies of the result and some benchmark methods are performed via numerical simulations, showing significant improvement of traffic efficiency and fuel economy with faster calculation.