Abstract
The exhaust emissions of newly registered automobiles in Thailand is assessed from a driving cycle based upon the standard of the European Economic Community Directive. This standard is suitable for European regions but may not be entirely appropriate for Thailand where the driving conditions are not the same. Thus, this driving cycle may not produce a realistic assessment of the emissions of the cars under Bangkok traffic. The objective of this study is therefore to develop a new driving cycle which can be used for the assessment of emissions and fuel consumption of vehicles traveling in Bangkok. A method for selecting representative road routes for collecting driving speeds is proposed. A gasoline passenger car is used to collect speed-time data along those selected road routes in Bangkok. The driving characteristics are analyzed from the speed-time data and its target driving parameters are defined and evaluated. The method for generating the driving cycle is described. Comparisons show that the target parameters of the developed driving cycle are much closer to those obtained from measured data than those calculated from the presently adopted European Cycle. It is hoped that the obtained driving cycle will produce more realistic results in the emissions and fuel consumption assessment tests on vehicles traveling in Bangkok.