Objective Evaluation System of Vehicle Fuel Economy, Performance and Drivability

Abstract:

Based on the traditional objective evaluation of vehicle fuel economy and WOT (wide open throttle) performance, the objective characterization of vehicle drivability were proposed, emphasizing on the four main aspects: POT (partial open throttle) response, accelerator pedal feeling, gear shift smoothness and tip in/tip out transient response characteristics. The objective characterization metrics including longitudinal acceleration response map, accelerator pedal acceleration linearity, acceleration gain, shock, acceleration RMS (root mean square), VDV (vibration dose value), etc. were investigated, and the consistencies of objective indicators and subjective evaluations were verified through correlation analysis. The fuel economy, performance and drivability comprehensive evaluation system was established based on multi objective balance. A diesel vehicle equipped with 6 automatic transmission was studied as an example, the vehicle and powertrain models were created based on AVL CRUISE software, and the economical and comprehensive shift strategies were generated based on AVL GSP (gear shifting program) tool, then the fuel economy, performance and drivability were contrasted and analyzed between different shift strategies, the effectiveness and practicability of the objective evaluation system were illustrated quantitatively.