Acceleration Response in Determining Vehicles Objective Driveability Assessment

Abstract

Vehicle driveability defined as smoothness of a vehicle operation at the will of the driver under all driving conditions. Driveability evaluation is conducted by giving subjective rating based certain test standard procedures. A group of test evaluators performed driveability test and gave individual rating based on subjective feeling. After discussion, a final overall rating is generated with consensus from all evaluators. Human subjective rating can be inconsistent due to physical health condition and individual preferences.Vehicle's acceleration profile can be associated with second order response. Every acceleration profileshas specific damping factorandnatural frequency.A study is conducted to determine the possibility of using second order parameter to setup an objective driveability assessment. Test vehicles with different acceleration conditionsare evaluated to determine driveability subjective rating. Acceleration profile for each vehicles is analyzed to determine its damping factorand natural frequency. A relation of damping factorand natural frequency with subjective driveability rating is established. The established relation of driveability is essential in providing guideline for future ECU calibration and tuning.