Handling Characteristics and Stability of the Steady-State Powerslide Motion of an Automobile

Powerslide of an automobile may be defined as a steady-state cornering motion at a large side slip angle of the vehicle, considerably large traction forces and a large negative steering angle of the handwheel. In this case the front wheels direct towards the outside of the turn. As this extrem driving condition, which can be seen e. g. in Rallye sports, is hardly addressed in literature so far, this paper investigates the respective handling characteristics. Therefore, a nonlinear four-wheel vehicle model is applied including nonlinear tyre characteristics, the load transfer between inner and outer wheels and the influence of the traction forces on the lateral tyre forces. A basic stability analysis reveals the unstable nature of the steady-state powerslide motion of a certain test vehicle. To approve the numerical findings, measurements have been performed with a sports utility vehicle with rear-wheel drive at various speeds on a wet circular test track.