Turning the corner: Lateral Dynamics in a vehicle
Steady State Handling/ Cornering Characteristics of a Vehicle
Handling or Cornering behaviour of the vehicle is an important vehicle performance measure. Handling defines the relationship between the driver input and the vehicle output during cornering. The simplest input can be the steering wheel angle and the output can be lateral acceleration or yaw rate. The degrees of freedom analysed here are generally yaw and roll of the vehicle apart from lateral motion. However, for this blog, I would leave out the roll motion of the vehicle.
The most commonly used metric to evaluate lateral dynamics of a vehicle is Understeer Gradient. It is calculated at steady state conditions but it can also infer performance under the conditions that are not quite steady state.
Regimes of Handling
One common question that usually comes up in handling studies is what acceleration levels are we talking about. At different acceleration levels, system dynamics is different. Most of the driving is done at low acceleration levels ( < 1 m/s2) with very few instances where vehicle goes to limit handling state.
