The Feasibility of Using an Instrumented Vehicle Equipped with Inertial Navigation Guidence System to Collect Roadway Grade and Cross-Slope Data for Safety Analysis
In 2005, the Federal Highway Administration (FHWA) requested the development for the initial version of the Model Minimum Inventory of Roadway Elements (MIRE). MIRE is a roadway inventory and traffic data collection data program that has a strong focus on improving the decision process in safety programs. MIRE is not a mandatory state program, but is strongly recommended based on its potential advantages. Some of the data required for MIRE was previously collected as a result of the requirements set from the Highway Performance Monitoring System (HPMS). This thesis concentrates on the feasibility of determining as-built grade and cross-slope data using an instrumented vehicle equipped with GPS-aided MEM Inertial System by Crossbow, eliminating the need to manually extract data from design plans or use other methods. Instrumented vehicles should provide time savings in the data collection process and sufficient results, within the acceptable limits, for safety analysis. A calibration was performed on the Inertial Navigation Unit (INU) to test for any bias that may be present. Roadway data was collected by traveling multiple runs in each travel lane in both directions on the SCDOT Test Road and several road sections in Atlanta, GA. The included analysis tests the calibration of the Inertial Unit by having a test road with high accurate as-built plans to test the grade, and survey data to test the cross-slope. The inertial unit data was processed and compared to the obtained data to see what the absolute error was to determine if the results were acceptable for safety analysis
