The use of INS/GPS in a highway survey system

The integration of an inertial navigation system (INS) and Global Positioning System (GPS) receivers in differential mode is investigated for application to highway survey systems. A mobile highway inventory system (MHIS) operated by Alberta Transportation is used as a first step in the realization of an all-purpose kinematic survey system. MHIS requirements of approximately 0.5 m in position, 10 cm-s^-1 in velocity, 0.5% in slope, and 0.2° in curvature appear obtainable with the integrated system. If these requirements can be surpassed, INS/GPS can be used for road surveys, possibly replacing conventional survey techniques. The authors briefly describe the MHIS and outline the benefits of using INS/GPS for accurate and reliable geometric data collection. They outline the mathematical models for INS/GPS integration. Road tests performed using INS/GPS over a well-controlled traverse are discussed, and results are given