Homologation process for ESP based vehicle models

摘要

Due to the difficult economical situation the vehicle manufacturers and their suppliers have to reduce their different expenses both in the design and in the production period. Therefore it is needed to simplify these processes. As a part of the current development the adequacy of the model is checked by a validation process with a continuous feedback. Our goal is to compare the predictions of the model and the measured data. However, the comparison of measurements on a test track with a vehicle model equipped with ESP requires more measurement processes. These measurements are time consuming and in order to provide accurate reproducibility they account for a significant part of the end-price of the product, which the costumer is not willing to pay in some cases. This paper deals with the validation process of the ESP systems on commercial vehicles. These vehicles have different superstructure and different subsystems, although a properly homologised model gives us the possibility to leave the multiple validation process decreasing the final costs of the vehicles. Such differences are the number of the axles, the axle base and track width, the type of the suspension, the type of the springs and the shock absorbers, and several other differences which have influence on the dynamics of the vehicle. The model used for the homologation should be complex and flexible enough, and it should be appropriate on international level, therefore we have to choose a highly adequate simulation environment. Therefore we have chosen the simulation software called Simpack, which is a multi body simulation programme. With this, we are able to model a complete vehicle, and after the validation of this model we can substitute the measurements with simulation. The homologation process ensures the model based adequacy, so if any parameter of the vehicle changes, we can choose a different vehicle unit, so finally we get appropriate simulation results. To reach this, it is necessary to create a model -in SimPack environment-which contains the properties of the fore mentioned vehicles. It is also important to name the input parameters that are relevant to different vehicles. After all if we have a basic vehicle model then with an appropriate validation the model will be proper for model-based homologation.