Road variability and its effect on vehicle dynamics simulation

• Main Author: Udas, Amit
• Other Authors: Chen, L-D.
• Format: Others
• Language: English
• Published: University of Iowa 2011
• Subjects: Mechanical Engineering
• Online Access: https://ir.uiowa.edu/etd/1097; https://ir.uiowa.edu/cgi/viewcontent.cgi?article=2481&context=etd

In the modern age, computer aided engineering software is used in nearly every engineering design application. In this thesis, a multibody dynamics vehicle model in LMS Virtual.Lab simulation platform was updated. The updates included measured hardpoint data of the vehicle studied, addition of two differential gear models to the vehicle drivetrain, and implementation of a multibody dynamics model of a trailer that is attached to the vehicle. To extend the length of the experimentally acquired road profile, a distribution function based methodology was developed to create road profile from the limited road data. The road parameter generated from the distribution function was used to recreate a road profile statistically representative of acquired road profile data. The updated vehicle dynamics model was validated by comparing the simulation results to the vehicle dynamics test results conducted at the Nevada Automotive Test Center. To validate the methodology for creating the road profile, vehicle dynamics simulation results with the distribution function generated road profile were compared to the results from the acquired road profile. The effects of road variability on the vehicle dynamics simulation were also examined. By using a Gamma distribution to define the road roughness, a sensitivity analysis was conducted to study how the variation in road roughness affects the vertical, longitudinal and lateral accelerations at the driver's location. The results show that the RMS values of the acceleration increase linearly with increasing mean roughness for variance up to ±30% and a quadratic response for variance up to ±100%.