Project Number: PSR-18-06

Funding source: Caltrans

Contract number: 65A0674 TO 005

Funding amount: $100,000

Performance period: 2/1/2019 to 4/30/2020

Project description

Despite the recent advancement of autonomous vehicle technology, performing lane changes in dense traffic environments remains an open challenge. One important issue is finding a suitable space to merge without putting either the lane changing vehicle or others in a situation which they cannot handle in case of an emergency. While humans often put themselves at risk for periods of time, autonomous systems must operate as safely as possible at all times without taking any such risks.

In this report we address the problem of cooperative lane change maneuvers where vehicles communicate with each other and negotiate the creation of safe spacings in order to merge without taking any safety risks. The proposed approach requires that the merging vehicle negotiates the creation of a safety gap in the destination lane and till the lane change maneuver is completed it operates as having two possible leaders, one in its own lane and one in the destination lane. In addition, the future following vehicle in the destination lane operates as if the merging vehicle has already changed lanes. This approach leads to a smooth creation of spacings for the vehicle to merge into while safety is guaranteed. Furthermore, we expand this solution to platoons of vehicles, develop the communication protocol to be followed, which includes a rule to avoid pos- sible conflicts, and propose measurement verification steps to identify sensor or communication failures. Extensive simulations are used to demonstrate and evaluate the approach under different conditions. They allow us to verify that the proposed control policy generates the desired smooth gap generation behavior. Moreover, we can conclude that the developed methods improve traffic safety and efficiency and reduce environmental impact.