The fallen-stone sensor and snow-depth meter (which measures snowdepth on roads) have been developed for the purpose of traffic safety. The fallen-stone sensor uses an Si bulk microphone which detects pulsing vibrations, from a detection plate, which occur when the plate is struck by a stone. Noise and vibration from traffic will not be sensed due to the construction of the detection plate, while the pulsing vibration of a 2 g to 10 kg stone falling from a height of 1 meter can be sensed exactly by the plate. The snow-depth meter uses a 26 kHz ultrasonic tone burst wave, and the depth of snow on a road is measured by the reflection time. The accuracy of this snow-depth meter is + or - 2 to 3 cm, within a measurement range of 0 to 100 cm, with temperature correction for sound velocity.

  • Corporate Authors:

    Matsushita Electrical Company, Limited

    3-15 Yakumonakamachi Moriguchi
    Osaka 571,   Japan 
  • Authors:
    • Makino, T
    • Miura, K
  • Publication Date: 1977-10


  • Japanese

Media Info

  • Features: References;
  • Pagination: p. 803-810
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00176607
  • Record Type: Publication
  • Source Agency: Engineering Index
  • Files: TRIS
  • Created Date: Jul 29 1978 12:00AM