Patent ID: 6049387
Filing Date: 2000-04-11
Classification: B60G,B60T,G01B

Abstract:
A process for determining the condition of a road surface, comprising:beaming light onto the road surface;dividing backscattered light from the road surface into spectral components;analyzing the spectral components of the backscattered light to obtain a spectral analysis; anddetermining a condition of the road surface with respect to a presence of at least one of water and ice, based on the analysis of the spectral components of the backscattered light;wherein said analyzing step includesarranging a wavelength-dependent plot of a backscatter intensity for the spectral analysis of the backscattered light as a product of a function having free parameters which represents a wavelength-dependent backscatter light spectrum of a dry road surface, and an exponential absorption term which describes a light transmission of a water layer having a defined thickness; andcalculating the free parameters via actual measured values to obtain an optimum approximation value;and wherein the condition of the road surface is determined based on the approximation value.