Auditory Alerts and Safety with Simulated Bicycles and Motor Vehicles

Bicycling has become an increasingly popular and environmentally friendly active transportation modality for many commuters across the nation. Consequently, as ridership increases so does the rate of bicycle–motor vehicle crashes, many of which are caused by reduced bicycle visibility and driver inattention. Therefore, one effective solution to improve bicyclist safety may be through the use of an audible bicycle alarm system to alert both the driver and the rider. A study was conducted to determine whether a unique auditory alert would be effective at reducing crash rates and whether a localized alert (i.e., an alert presented from the driver’s perspective) would improve the driver’s responsiveness in avoiding a potential collision. A driving simulator study tested car horn sounds, an experimental bike alert, and no auditory alert in different potential collision scenarios to measure collision rates and other collision avoidance metrics. Findings indicated that the experimental bike alert contributed to fewer relative crashes than the horn sound and no sound on bicycles, motor vehicles were struck more frequently than bicycles, collisions were more likely to occur from the front than the sides, and collisions were more likely for drivers going straight than when making turns. Taken together, the findings suggest that an alarm designed to be specifically compatible with bicycles is more effective than auditory alerts from other sources.

Objective and subjective relationships of non-linguistic sounds

Our hearing is used to understand speech as well as non-linguistic sounds (NLSs; car horn, laughter, etc.), but how we perceive them and how we correctly identify them appears to differ from the processes used in speech perception. We examined how differences in objective features of different NLSs influence their subjective perception and correct identification.To do this we utilized a database of 158 NLSs which had been characterised by 12 normal-hearing young adults for the subjective perceptions of complexity, pleasantness, and familiarity, and for accuracy of identification. Using various mathematical, acoustical, and statistical approaches from studies of complex waveforms, we extracted 15 objective features from the NLSs. These objective features were then used to correlate with the subjective perceptions and the accuracy of naming for those NLSs. We additionally used a series of multivariate techniques to establish whether combinations of objective features for NLSs could also account for their differences in subjective perceptions or accuracy of naming. Finally, we also noted the categories of NLSs by their source and used ANOVAs to find if significant differences could be found between these categories for objective features, subjective perceptions, or accuracy of naming.Significant (p<0.05) inter-relationships between the perceptions and accuracy of naming were indentified, which allowed us to determine familiarity as the least independent subjective perception in our study, i.e., it was highly correlated with the other perceptions and accuracy of naming. Significant (p<0.05) inter-relationships between several objective measures were also found, allowing us to identify the salient objective measures. We found several salient objective measures which significantly (p<0.05) correlated (individually) with the perceptions and accuracy of naming for NLSs in our database. Further, combinations of these measures correlated even more significantly; however there were limits to the amount of variation which could be explained with our set of objective measures. Nevertheless, given the objective information of the NLSs, our database could be mathematically categorised into clusters of objectively similar NLSs. These resultant clusters had significant (p<0.05) perceptual differences for complexity and significant (p<0.05) differences in their accuracy of naming. Subjective and objective differences were also noted among different source-based categories of NLSs in the entire database, though there were fewer significant (p<0.05) differences among these categories than there was potential for.Our study marks one of the first and most comprehensive efforts to relate objective features to the subjective perceptions of complexity and familiarity in NLSs, as well as adding substantially to our understanding of the same relationships for pleasantness and for identification accuracy. These findings have implications for the development of novel clinical audiometric testing by providing a well-characterised database of NLSs to test a patient's ability to process spectral and temporal components of sound.

Multi-physics phenomena influencing the performance of the car horn

Usually cars are equipped with disk horns. In these devices electromagnetic energy is converted into mechanical energy of two nuclei that vibrate and impact each other – the impacts excite the disk that radiates sound. This paper aims at understanding the results of acoustic tests carried out on horns with different excitation voltages and different mounting brackets. Since many non-linear phenomena are inherent in the vibrations of the nuclei, a detailed model of the electromechanical system is developed. Results show the dependence of operating frequency on the input voltage and the role played by the various mechanical and electrical parameters on the dynamics of the horn. Particular non-linear effects, like sub-harmonic excitation, are presented and discussed. A general agreement between experimental results and numerical simulations is found.

The Invention of the Car Horn Intelligent Display System

This article describes a system device capable of displaying a car outside sounds, the system device sound signals collected by the sound sensor , combined with the single-chip analytical processing Finally, LED lights, buzzer and other electronic actuator smart car external speaker sound source direction and strength of the drivers are able to accurately determine the rear of the vehicle the location and intentions, in order to take more appropriate driving route and speed, so that the operation of the vehicle more intelligent, is conducive to maintaining the smooth flow of traffic, more effective in reducing traffic accidents, to further improve automotive safety system, greatly improves the safety performance of vehicles.