Minimum time manoeuvring: The significance of yaw inertia

A formal method for the evaluation of the minimum time vehicle manoeuvre is described. The problem is treated as one of Optimal Control and is solved using a direct transcription method. The resulting Non Linear Programming p roblem is solved using a Sequential Quadratic Programming (SQP) algorithm f or constrained minimisation of a multivariable function. The optimisation p rogram is used to investigate the effect of the yaw moment of inertia on ve hicle performance in a double lane change manoeuvre. The method is shown to have excellent capabilities to predict the vehicle maximum performance in transient conditions and to perform sensitivity analysis. The influence of yaw inertia on the minimum manoeuvre time is found to be surprisingly small . The extension of the method to larger problems, e.g., lap time simulation , is also discussed.