Remote vehicle exhaust emission sensing for traffic simulation and optimization models

This paper presents the development of the ONROAD vehicle exhaust emission model for estimating CO and HC emissions. This model is developed based on the on-road emission data collected from five highway locations in Houston area using a remote emission sensor. The ONROAD emission estimation model establishes relationships between the on-road vehicle exhaust emission rates and a vehicle's instantaneous speed profile. Since a vehicle's instantaneous speed profile is a function of different traffic demand and control scenarios, this emission model can be used to estimate the emission implications of alternative traffic control and management strategies. Because of the aggregate nature of the ONROAD emission model, it can be easily incorporated into a traffic simulation or dynamic traffic assignment model where a vehicle's instantaneous speed profile can be tracked consistently. Hence, this emission model is ideal for traffic simulation and optimization analyses.