Development of a new 3D transverse laser profiling system for the automatic measurement of road cracks

Abstract

Over the last 6 years INO (the National Optics Institute of Canada) has, in collaboration with the MTQ (Ministere des Transports du Quebec), been developing and testing a new technology called the LCMS (Laser Crack Measurement System). The LCMS consists of two high performance laser profilers that are set up in such a way that the complete transverse profiles of a road lane can be measured. In addition to acquiring high resolution 3D road profiles, algorithms were developed to analyze the 3D data in order to automatically extract crack data including crack type (transverse, longitudinal, alligator and sealed cracks), crack severity and crack location (presence in bands). Further testing of the system was performed in order to demonstrate that the system can also be used to evaluate rut depth, to detect pot holes and patching, and to measure the macrotexture of the road surfaces. This paper will explain the 3D laser technology and optical configuration used by the LCMS system. Examples of raw data acquisition and of the processing steps needed in order to be able to extract the different road surface characteristics (cracks, pot holes, macrotexture, etc) will also be presented. Finally, the specifications achieved by the system will be summarized, and the preliminary results obtained during the different test phases will be presented.