ALIGNMENT DATA COLLECTION OF HIGHWAYS USING MOBILE MAPPING AND IMAGE ANALYSIS TECHINIQUES

摘要

The Mobile Mapping System (MMS) is an advanced tool useful in the survey of linear infrastructuressuch as highways. One of its main applications is the collection of three-dimensional data used to derivethe geometric characteristics of roads (i.e. alignment, lane width, shoulder dimensions) and otherelements of the road surroundings (i.e. traffic signs, lighting systems, barriers, drainage elements). It is atool which is useful in several applications and research fields (i.e. road cadastral, safety and humanfactor studies, road infrastructure quality control).In this paper, the results of an investigation dedicated to the evaluation of the geometriccharacteristics of highway alignment are presented. The program investigation has been conducted byusing image analysis techniques to process the data collected by a dedicated MMS. A prototype vehiclehas been developed and fitted out with three geodetic GNSS receivers, a low cost inertial measurementunit (IMU) with a built-in GPS receiver (GPS/IMU) and a webcam.The highway alignment has been derived as the average point of the two trajectories followed bythe MMS or alternatively in accordance with the horizontal markings of the pavement. The trajectorieshave been derived from GPS/IMU data processing while the markings have been automatically recordedby a webcam. Each frame has been geo-referenced on the basis of the data collected from the GPS/IMUsensor. A data validation procedure has been carried out to verify the accuracy of the proposed surveyingmethod.