Modelling

When modelling vehicles and transmissions GIF pursues three approaches:
The powertrain can be modelled - particularly in its longitudinal dynamics - in order to study occurring vibration modes. Furthermore, transmission control algorithms can be tested on the model and fuel-consumption calculations as well as driving dynamics simulations can be performed.
Mostly GIF uses MATLAB/Simulink or ITISim for the programming.

MATLAB/Simulink-model for the controls development

GIF has represented numerous vehicle types in models. The main interest is directed towards the powertrain, particularly with regard to the transmission.
By means of vehicle data the models are at first parameterised to simulate vibrational excitations or the acting of transmission controls. The results are compared with the vehicle and the test bench measurements to perform a validation of the model. After successful validation precalibrations can be developed and tested which only require slight modifications in the vehicle. This leads to a significant reduction of development time for extensive projects.

Modular vehicle models for driving dynamics and fuel-consumption analysis

By means of the vehicle models and control algorithms the expected driving dynamics and fuel consumption are predicted and compared to other transmission types.

To this end acceleration times are tested, e.g. for 0-100 km/h, 60-100 km/h, 80-120 km/h and 0-4 m. The fuel consumption is normally calculated by means of constant-speed driving and standard cycles such as the NEDC.