AN AUDIBLE AUTOMOBILE BACK-UP PEDESTRIAN WARNING DEVICE - DEVELOPMENT AND EVALUATION

The purpose of the study was to develop and field-test an audible back-up warning device for use on automobiles. Detailed criteria of pedestrian age and hearing ability combined with noise characteristics of typical accident sites provide the basis for selection of a warning signal format. The warning signal (a tone at 1250 Hz pulsed on for 0.1 sec and off for 0.2 sec) is generated by a small loudspeaker mounted at the rear of the vehicle. An essential element of the design, that the system sense the ambient level and adjust its output accordingly, results in a warning signal level approximately equal to the A-weighted noise level throughout the danger zone. This is comparable to a level at least 10 dB above the pedestrian's detection threshold. Evaluation of a prototype system was conducted in typical parking sites using pedestrian subjects of opportunity. Results comparing the normal situation with a test sequence using the warning signal indicated a tenfold improvement in the number of pedestrians warned of the presence of a backing vehicle.

Media Info

  • Pagination: 165 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00151171
  • Record Type: Publication
  • Source Agency: National Technical Information Service
  • Report/Paper Numbers: WR-76-12 Final Rpt., DOT-HS-802-083
  • Contract Numbers: DOT-HS-5-01185
  • Files: NTIS, NTL, TRIS, USDOT
  • Created Date: Mar 30 1977 12:00AM