Content area
Full text
ENGINEERS NEED ACCURATE base data for planning, design, construction and management of all facets of the transportation environment. In the modern era, where quick turn-around time, and Health and Saftey are real factors to deal with, the traditional methods of ground survey had to be revised.
The latest technology uses a combination of LIDAR scanners, cameras, GPS and other equipment for fast, accurate data capturing. One of these methodologies is high -accuracy three-dimensional mobile mapping.
HIGH-ACCURACY 3D MOBILE MAPPING
A three-dimensional mobile scanning unit comprises laser sensors, navigation sensors (IMU), GPS and high resolution cameras. This mobile mapping range of equipment enables a rapid accumulation of data at speeds of up to 70 km per hour. Accuracies are in the same order and better (1 cm) than conventional ground survey methods. The equipment can be mounted on any moving vehicle, including trolleys (railway lines) and boats. Data can be extracted automatically or manually, and the software has unique object recognition abilities to identify objects such as road signs, markers, curbs, overhead obstacles, etc. Note that there are many different models available from Google maps type of applications (5 m accuracy and no heights) to 1 cm accuracy suitable for road resurfacing, design and volumes. The proposed methodology is for the latter, which means one set of accurate data.
DIFFERENCE BETWEEN 3D MOBILE MAPPING AND GROUND SURVEY
With conventional survey methods, cross sections are...