Vehicle optimal road departure prevention via model predictive control

This article addresses the problem of road departure prevention using integrated brake control. The scenario\udconsidered is when a high speed vehicle leaves the highway on a curve and enters the shoulder or another lane,\uddue to excessive speed, or where the friction of the road drops due to adverse weather conditions. In such a scenario,\udthe vehicle speed is too high for the available tyre-road friction and road departure is inevitable; however, its effect can\udbe minimized with an optimal braking strategy. To achieve online implementation, the task is formulated as a receding\udhorizon optimization problem and solved in a linear model predictive control (MPC) framework. In this formulation, a\udnonlinear tire model is adopted in order to work properly at the friction limits. The optimization results are close to\udthose obtained previously using a particle model optimization, PPR, coupled to a control algorithm, MHA, specifically\uddesigned to operate at the vehicle friction limits. This shows the MPC formulation may equally be effective for vehicle\udcontrol at the friction limits. The major difference here, compared to the earlier PPR/MHA control formulation, is that\udthe proposed MPC strategy directly generates an optimal brake sequence, while PPR provides an optimal reference\udfirst, then MHA responds to the reference to give closed-loop actuator control. The presented MPC approach has the\udpotential to be used in futur