Sideslip angle identification for tires performance development

During these six months the goal was to compute some parameters of dynamic vehicle such as sideslip angle and cornering stiffnesses, applying a linear Kalman filter, using as acquisition system either the CAN network or an IMU (Inertial measurement unit) platform. Indeed, this method works obtaining data in either case from the CAN system and from the IMU. In the first part of the thesis, some general theory topics, of dynamic vehicle especially about sideslip angle estimation. A general explanation of vehicle models particularly for the bicycle model, the model picked for the sideslip angle estimation. The Kalman filter will be explained, first generally then a comparison trough different types of Kalman filters; the linear Kalman filter, the EKF (Extended Kalman filter) and the UKF (Unscented Kalman filter). All the sensors used and the approach picked will be explained in detail. Furthermore a brief introduction of the code and the steps followed will be described. In the second part, the analysis of the car behaviour for different standard manoeuvres will be showed. The manoeuvres will cover the static and dynamic behaviours of the car, in time-domain and in frequency-domain. These analysis have been done using FCA software, developed by the Fiat center of research. The cornering stiffness estimation method will be explained. This method is based on a cinematic model, used to estimate the sideslip angle as a first estimation then to use the angle to estimate the cornering stiffness. The last point and most important aspect of this thesis, is the comparison between the results, obtained from the estimations, and the measured values. The measured sideslip angle values are computed using an optical sensor and the goal of this thesis is to avoid the use of this sensor for economic and practicality reasons. These comparisons will be done for the standard manoeuvres and for the standard lap, for different types of cars, either ICE (Internal combustion engine) and Hybrid cars.