| 摘要 |
<p>PURPOSE: To provide a snow-covered road surface detecting device designed to be capable of accurately detecting the snow-covered, dry, and frozen states of a road surface through detection over a wide range. CONSTITUTION: This snow-covered road surface detecting device includes an image pickup means 11 for photographing a road surface, a frame memory 13 in which image outputs from the image pickup means 11 are stored in the form of digital signals, a Fourier transformation part 14 by which the digital signals stored in the frame memory 13 are subjected to Fourier transformation, a memory 15 in which a power spectrum image on a frequency space calculated through transformation by the Fourier transformation part 14 is stored, a filter part 16 which extracts power spectrum components in the power spectrum image, and a judging part 17 which outputs a snow-covered state when a characteristic value extracted by the filter part 16 is greater than a set value and which outputs a dry or frozen state when the former is smaller than the set value.</p> |
