Study on Correlation of Commercial Vehicle Axle Response with Road Profile for ISO Road Class Categorization and Durability Analysis

Durability analysis is essential for vehicle validation and is carried out with the inputs of different road conditions. The selection of roads for durability analysis is critical and should represent the actual working conditions for the selected vehicle. Generally, the road conditions are subject to change with respect to time. To overcome the above, road profile data is an essential parameter which helps to represent and categorize roads in terms of ISO (International Organization for Standardization) road class. The ISO road classes objectively classify the roads with respect to roughness. This classification holds good by categorizing the signals to the respective road classes rather than different test roads.

The road profiles are measured using inertial profiler methodology along with vehicle acceleration and displacement responses, also analyzed and categorized with respect to ISO road class. Initial study and analyses are carried out to process axle absolute displacement from axle acceleration and effective road profiling from raw road profile data. Effective road profile and axle absolute displacement are correlated with respect to each road class considering the effect of load and speed variations. This correlation work enhances to categorize in terms of ISO road class for vehicle response data without road profile measurements. It also extends to compare and generate axle response from respective road profile. It results in reduction of repetitive road load data acquisition and objective selection of signals for durability analysis.