VIASAT - A mobile highway survey system of high accuracy

The prototype development of VIASAT, a precise mobile survey system for road inventory and associated GIS applications, is discussed. The system integrates inertial, satellite, and charge coupled device (CCD) camera technology to achieve an overall positioning accuracy of 0.3 m (1 ft) or better for all objects within a 50 m corridor on both sides of a highway. Combining the high positioning accuracy of Global Positioning System (GPS) with the precise pointing accuracy of inertial navigation system (INS) a cluster of CCD cameras will be accurately positioned and oriented at any instant of time. Using this information, objects along the highway can be precisely surveyed in three dimensions by processing the digital image information of the CCD camera cluster. The system concepts are discussed. Special emphasis is given to sensor integration, testing of the INS/GPS component and data flow from the acquisition process to the workstation environment.