<title>Vehicle emission sensing and evaluation using the Smog Dog in Houston</title>

Abstract

The advanced remote vehicle emission sensing equipment, Smog Dog, is a cost-effective infrared technology designed to measure the levels of vehicle exhaust. This paper presents and demonstrates a research effort for using the Smog Dog to conduct the on-road vehicle exhaust emission collection in the city of Houston, develop modal sensitive emission models and evaluate the EPA approved MOBILE5A emission factor model. The vehicle emission data collection is designed in a manner that various vehicle's modal events such as the acceleration and deceleration under the on-road driving conditions are considered. The Smog Dog remote mission sensor can not only collect the emission concentrations of hydrocarbon, carbon monoxide and oxide of nitrogen but also simultaneously detect the vehicles' instantaneous speeds and acceleration rates. Thus a vehicle's emission rates, which are converted from the collected emission concentration levels, can be functions of its instantaneous speed and acceleration rate. In addition, the Federal Test Procedure driving cycles are emulated using the emission versus speed profile relationships and the resulted emission rate for a predetermined average driving speed can then be compared with the emission factors produced by MOBILE5A. Since the emission models, that are developed based on the on-road emission data collected using the Smog Dog, naturally reflect the on-road driving conditions and the vehicle fleet combinations, they can potentially be used to evaluate the vehicle exhaust emission implications of various advanced traffic management strategies.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.