An algorithm for the estimation of the longitudinal and lateral forces exerted at wheel level between tires and ground is presented. Starting from a modified version of the single track vehicle model, which also includes the steady-state effect of pitch and roll on the planar movement of the vehicle, the structure is designed as a cascade of two Sub-Optimal Second Order Sliding Mode (S-SOSM) observers, featuring an adaptive feedback which helps improving the accuracy of the estimation of the longitudinal forces. The presented approach is purposely designed so that only standard sensors, which are usually available in commercial vehicles, are exploited. In order to alleviate the high frequency vibrations introduced by the Sliding Mode technique, an EKF is added as a second step, which considers the output of the S-SOSM observer as a noisy measurement, hence the virtual sensor nomenclature. The method is evaluated on experimental data, displaying good performance both in terms of accuracy and chattering alleviation.

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In this work a system for the estimation of the forces (both longitudinal and lateral) exerted between the tires and the road is presented. Starting from two of the most commonly used descriptions of the vehicle dynamics, the single-corner and the single-track models, a system composed of Sub-Optimal Second Order Sliding Mode observers in a cascade structure plus an adaptive element is developed and verified to be effective in conditions in which the effect of the weight transfer can be neglected. One notable property of this approach is that only standard sensors, which are present in most of the stock cars, are exploited. The practical implementation is done using a switched/time-based adaptation law for the gains of the observers, in order to be able to track the quantities in a wide range of conditions while keeping the chattering low. Simulation results are presented in IPG Car-Maker.

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Charge unbalance is one of the key issues for seriesconnected Lithium-ion cells. Within this context, model-based optimization strategies have proven to be the most effective. In the present paper, an ad-hoc electrochemical model, tailored to control purposes, is firstly presented. Relying on this latter, a general nonlinear MPC for balancing-aware optimal charging is then proposed. In view of the possibility of a practical implementation, the concepts are subsequently specialized for an easily implementable power supply scheme. Finally, the nonlinear MPC approach is validated on commercial cells using a detailed battery simulator, with sound evidence of its effectiveness.