**Article details**

**Title: **Pressure Evolution within the Braking System of a Vehicle: Getting a Generalized Model

**Author(s): ***Marin Marinescu* *Radu Vilău* *Valentin Vînturiş*

**Abstract: **There are lots of methods to issue mathematical models that can cover better or worse the real life phenomenon. Most of the mathematical models are using parameters that are rather estimated than real. Hence, a higher or a lower degree of accuracy can be expected. Since most of the input variables are estimated, low accuracy level is usually achieved. In this respect, the authors of this paper tried to offer an alternative model of a real-life mechanical amount simulation. This model starts over a larger amount of tests, where one could get a database, large enough to backup the further behavior of the system. In this respect, we have measured the pressure variation of the brake cylinders of a vehicle, as a function of the input pressure developed by the servomechanism of the system. Based on this large amount of data, we used a parametric mathematical model based on polynomial methods to estimate the generalized model. We can strongly confirm that the model is suitable – within a reasonable error margin – for all the braking systems of the specified kind of vehicles.

**Keywords: **braking system, parametric model, transfer function, global model.

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