Real Driving Emission (RDE) Assessment for Motorcycles Using a Random Cycle Generator (RCG)

To protect the atmospheric environment conservation, regulations regarding vehicle exhaust gas emissions have become increasingly stringent over the years. For the case of light duty vehicles (LDVs), Real Driving Emission (RDE) assessments based on Portable Emission Measurement System (PEMS) measurements are being introduced. However, the application of PEMS measurements to motorcycles presents several challenges, including reduced measurement accuracy due to the small engine displacement and number of cylinders, and increased weight due to the PEMS installation. Therefore, an alternative evaluation method that does not rely on PEMS is required. In this study, we have developed a Random Cycle Generator (RCG) to provide an evaluation method that can be performed in a laboratory environment. The RCG allows the creation of evaluation modes by combining different speed patterns of motorcycles. It can generate arbitrary driving cycles that take into account the average and upper limits of regional driving characteristics, allowing accurate emissions measurements to be made in the laboratory. As a result, the RCG-based method is considered a viable alternative to PEMS-based RDE assessment.