[Blindtlk] Press Release: Hybrid Cars Harder to Hear

[David Andrews]

>
>University of California, Riverside Press Release:
>
>Hybrid Cars Are Harder to Hear
>
>Quiet vehicles may pose greater risks to pedestrians, UCR psychologist finds.
>
>RIVERSIDE, Calif. – Hybrid cars are so quiet 
>when operating only with their electric
>motors that they may pose a risk to the blind 
>and some other pedestrians, research by a
>University of California, Riverside psychologist suggests.
>
>Preliminary results of the on-going research 
>project show that hybrid cars operating at
>very slow speeds must be 40 percent closer to 
>pedestrians than combustion-engine
>vehicles before their location can be audibly 
>detected, said Lawrence Rosenblum,
>professor of psychology. Those findings have 
>implications for pedestrians who are blind,
>runners, cyclists, small children, and others, he said.
>
>“There is a real difference between the 
>audibility of hybrid vehicles and those with
>traditional internal combustion engines that 
>could have effects on the safety of
>pedestrians which need to be studied,” Rosenblum 
>said. “Our preliminary findings could
>mean that there is an added danger with hybrid 
>cars, particularly at intersections and in
>parking lots.”
>
>In a research project funded by the National 
>Federation of the Blind, Rosenblum made
>audio recordings of hybrid and combustion-engine 
>cars in a quiet parking lot. The
>vehicles moved no faster than 5 miles per hour 
>to assure that the hybrid car operated only
>with its electric motor. Subjects in a lab 
>listened to the recordings and indicated when
>they could hear from which direction the car 
>approached. Subjects could make these
>judgments sooner when listening to the 
>combustion-engine car than when listening to the
>hybrid car.
>
>At speeds above 20 to 25 miles per hour hybrid 
>cars likely generate enough tire and
>aerodynamic noise to make them sufficiently audible, Rosenblum said.
>
>“This research provides evidence that hybrid 
>cars, when operating in silent mode, pose a
>substantial risk to blind people and other 
>pedestrians. We hope that regulators and car
>manufacturers will take notice of these results 
>and take steps to eliminate this risk,” said
>Dr. Marc Maurer, president of the National 
>Federation of the Blind, a 50,000-member
>advocacy organization for people who are blind or have low vision.
>
>Rosenblum, who is an adviser to the Society of 
>Automotive Engineers and sits on
>committees that make recommendations to the auto 
>industry, has spent many years
>researching perception of approaching cars and 
>whether there are similarities between
>visual and auditory perception of approach.
>
>“I really do feel this is an issue for more than 
>those who are blind,” he said. “We’re also
>talking about bike riders, runners and others. 
>Walking around with my kids in a parking
>lot makes it very clear that I’m using hearing 
>and vision to determine where things are.”
>
>Rosenblum is continuing the study with greater levels of background noise and
>eventually will test people who are blind in 
>parking lots to determine the level of risk. In
>April he will meet with Stanford University 
>researchers who are developing different
>sounds that would enhance the ability of 
>pedestrians to hear approaching hybrid and
>electric cars.
>
>“Everyone’s aware of the issue,” he said. 
>However, Rosenblum said, “We are not talking
>about major changes to the way automobiles are 
>designed, but about slightly increasing
>their audibility when they are traveling slowly. 
>Only a subtle sound enhancement should
>be required.”
>
>###