Acoustic characteristics of hybrid electric vehicles and the safety of pedestrians who are blind

PDFProceedingsBlind personsAcoustic propertiesHybrid vehiclesElectric vehiclesPedestrian safetyHuman factorsJohn A. Volpe National Transportation Systems Center (U.S.)Hastings, AaronScarpone, ChrisSamiljan, RobertGaray-Vega, LisandraPollard, John K.John A. Volpe National Transportation Systems Center (U.S.)NTL-ENERGY AND ENVIRONMENT-ENERGY AND ENVIRONMENTNTL-ENERGY AND ENVIRONMENT-Environment ImpactsNTL-PEDESTRIAN AND BICYCLES-PedestriansNTL-SAFETY AND SECURITY-SAFETY AND SECURITYNTL-SAFETY AND SECURITY-Vehicle DesignNTL-SAFETY AND SECURITY-Human FactorsVolpe National Transportation Systems Center, Technical Reference CenterQuieter cars such as electric vehicles (EVs) and hybrid electric vehicles (HEVs) may reduce auditory cues used by pedestrians to assess the state of nearby traffic and, as a result, their use may have an adverse impact on pedestrian safety. In order to document differences in the sound levels of HEVs and internal combustion engine (ICE) vehicles, the authors measured the sound pressure level in one-third octave bands of three HEV and three corresponding ICE vehicles for the following operating conditions: idle, backing up at 5 mph; approaching at a constant speed (6, 10, 20, 30, and 40 mph); accelerating from stop, and slowing from 20 to 10 mph at 3.28 ft/s2. Sound level results comparing the HEVs and ICEs are presented. In general, HEVs have lower sound levels than ICEs for operating conditions below 20 mph, but above 20 mph, the sound from road-tire interactions dominates and the sound levels of the two vehicle types converge