INSTITUT FRANCAIS DES SCIENCES ET TECHNOLOGIES DES TRANSPORTS

INSTITUT FRANCAIS DES SCIENCES ET TECHNOLOGIES DES TRANSPORTS, DE L’AMENAGEMENT ET DES RESEAUX Introducing Forward Scattering in Adaptive Rear Lighting Systems Romain GALLEN (CETMEF, Brest) Nicolas HAUTIÈRE (IFSTTAR, Paris) Eric DUMONT (IFSTTAR, Paris) Michèle COLOMB (CETE, Lyon) 27 th Session of the CIE South Africa 2011 D 4 -PP 26

Introducing Forward Scattering in Adaptive Lighting Systems D 4 -PP 26 • Question addressed – How to adapt rear-lamp intensity in fog? – Estimate optical range – Inverse Beer-Lambert law Forward scattering • Naïve solution Beer-Lambert Radiation fog Advection fog • Problem – Forward scattering is neglected – Over-correction of intensity results in glare 27 th Session of the CIE, South Africa 2011 2

Introducing Forward Scattering in Adaptive Lighting Systems • Contribution #2 – Forward scattering index based on the relative error on estimated intrinsic signal luminance Estimated Vmet (m) – Improved camera-based optical range assessment method 2 -lamp method N-lamp method bigger droplets Vmet (m) Relative error on estimated L 0 • Contribution #1 D 4 -PP 26 FS=3. 5 FS>4 3<FS<4 2<FS<3 FS<1 1<FS<2 Vmet (m) • Tests in virtual and artificial fog 27 th Session of the CIE, South Africa 2011 3

Thank you for your attention! D 4 -PP 26 Ifsttar www. ifsttar. fr nicolas. hautiere@ifsttar. fr 27 th Session of the CIE, South Africa 2011 4