Virtual Optimization of Vehicle and Powertrain Parameters with Consideration of Human Factors 2005-01-1945
The rapidly growing complexity and the growing cross linking of powertrain components leads to longer development times, especially in the vehicle calibration process. The number of systems which need to be fitted to each other and the number of parameters to be calibrated in the particular systems are increasing tremendously. The extensive use of simulation promises to reduce the calibration effort by providing pre-optimized parameter sets.
This paper describes a new simulation methodology by the interlinking of advanced vehicle simulation and evaluation tools, in particular the AVL-tools CRUISE, VSM and DRIVE. This methodology allows to semi automatically pre-optimize powertrain and vehicle parameters before hardware is involved.
So far the pre-calibration of vehicle and powertrain parameters by simulation was not satisfying because of the missing of a reliable evaluation tool for the produced simulation results. The measurement and evaluation tool DRIVE represents this missing link in the optimization loop. DRIVE allows the user to evaluate the simulation results objectively based on experience collected in many years of on road vehicle testing.
A special designed optimization routine allows the user to decide which vehicle or engine parameters shall be optimised during an optimization process. All DRIVE criteria ratings and physical parameters can be used as either targets or for limits for the optimization.
A dual clutch transmission powertrain serves as an example to show how the calibration process can be supported, accelerated and verified from the concept phase to start of production (SOP) by simulation. It could be proven that a shifting process had been significantly improved by pre-optimizing the relevant parameters. The subsequent performed vehicle tests have proven that the parameter sets optimized in simulation provided an excellent base for vehicle tests and after some fine tuning, the vehicle performance results regarding driveability, produced in simulation could be repeated on the road.
Summarizing, the presented combination of advanced simulation and evaluation tools allows a pre-optimization of vehicle and powertrain parameters with a reliable virtual consideration of human driving feeling.