Development of a grade sensitive transit bus driving cycle in San

Existing bus driving cycles fail to account for grade effect on emissions and fuel economy. In cities with hilly terrain, such as San Francisco, this may significantly underestimate bus emissions. In this paper, we develop a bus driving cycle specifically for San Francisco that incorporates grade. The collected data are analyzed with a typical cycle generation method-bottom-up method. Root Mean Square (RMS) error and Information Value (IV) of speed and grade data are used to choose the most representative cycle. The resulting San Francisco Driving Cycle is validated by statistically comparing to the collected dataset. The cycle development methodology is applicable to other cities as well as to light-duty vehicles and this research. This research will provide valuable information to SF with respect to future policy decisions on what kinds of buses best fit SF with consideration of both emissions and fuel economy data.