Quiet hybrid cars pose a hazard to pedestrians that simulated engine noise could mitigate
Important pedestrian safety issues have emerged with the advent of hybrid and electric vehicles. These vehicles are relatively quiet—they do not emit the sounds pedestrians and bicyclists are accustomed to hearing as a vehicle approaches them on the street or at an intersection. In a recent study, human factors/ergonomics researchers examined participants' preferences for sounds that could be added to quiet vehicles to make them easier to detect.
Though the safety of quiet vehicles has become an issue for pedestrians in general, it is also of concern to the National Federation for the Blind, which has called for quiet vehicles to emit a continuous sound and for additional research on the subject. The authors suggest that older individuals with diminished sensory and motor skills should also be considered as solutions are developed.
In their paper published in the Proceedings of the Human Factors and Ergonomics Society, 52nd Annual Meeting, Patrick Nyeste and Michael S. Wogalter of North Carolina State University evaluated responses of 24 participants (mean age = 19.4 years) to six categories of sounds that might be added to quiet vehicles: engine, horn, hum, siren, whistle, and white noise. Three variations of each type of sound were tested.
Study participants rated automotive engine sounds by far the preferred category, followed by white noise and hum. The authors suggest that these categories of sounds rated highly because they are associated with the engine sounds of conventional motor vehicles.
Automakers have continually worked to refine passenger vehicle power trains to be smoother and quieter but now find themselves faced with demands to make their quietest vehicles louder. Noise pollution caused by adding sounds to these vehicles could be limited by the use of a "smart" system that would change the level of emitted sound depending on the levels of vehicle and background environmental sound. These systems would turn themselves off if the vehicle produces adequate sound on its own.
At least one automaker, Lotus Engineering, has attempted to address the quiet hybrid issue. The company introduced "Safe and Sound," which mimics the sound of an internal combustion engine and operates when the vehicle is in electric-only mode.
The authors note that their research is also applicable to silent-engine vehicles such as electric golf carts, bicycles, wheelchairs, and Segways, which have caused injuries because of their quiet operation.
Research to further define the issues involved and develop possible solutions is being conducted by the National Highway Traffic Safety Administration, as well as by automobile manufacturers and the Society of Automotive Engineers International. The U.S. Congress is considering the Pedestrian Safety Enhancement Act of 2008, which would require the Secretary of Transportation to study and implement regulations for hybrid, electric, and other silent-engine vehicles to emit nonvisual alerts for pedestrians.
Lois Smith | EurekAlert!
The Great Unknown: Risk-Taking Behavior in Adolescents
19.01.2017 | Max-Planck-Institut für Bildungsforschung
A sudden drop in outdoor temperature increases the risk of respiratory infections
11.01.2017 | University of Gothenburg
An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
19.01.2017 | Event News
10.01.2017 | Event News
09.01.2017 | Event News
20.01.2017 | Awards Funding
20.01.2017 | Materials Sciences
20.01.2017 | Life Sciences