In this post, we’ll have a closer look to a new control technology announced by Mazda
Furthermore, we will explain why the car is easier and more safety to drive for the driver in terms of vehicle dynamics behaviour.
G-Vectoring Control (
GVC) as the basis
The basic control technology is the already used GVC. It helps the driver to use less steering wheel angle in turn-in and turn-out using the engine torque in order to change the vertical loads on front/rear tires.
When we push or release the throttle pedal on our car we change the amount of torque produced by the engine; the effect is a change in longitudinal acceleration and so a longitudinal load transfer. When we approach a corner (especially mid-speed corner) and we start to move the steering wheel, the system recognizes we are in turn-in and cut a little of engine torque, transferring more vertical load on the front axle. The effect is a higher lateral force on front tires and a less understeering vehicle. The driver’s feeling is a more direct/precise steering wheel. In turn-out, when the steering wheel angle starts to reduce, the system works in the opposite way and the vehicle becomes more stable, i.e. more understeer on turn exit. It is able to recognise in which of the two states the vehicle is.
G-Vectoring Control Plus
On the GVC Plus a direct yaw rate control system is added using brakes.
In this evolution the systems work together: the “old” one during turn-in, and the new one during turn-out, applying brake torque on the front outer wheel in order to generate a yaw moment that enhances the vehicle attitude to follow a straight line path.
Also in this case the effect on driving is a more direct steering wheel feeling and a more safety driveability. The latter aspect is visible also during emergency manoeuvres, for example, a fast line change or double line change, where the effect of GCV Plus allows a faster e more safety trajectory change associated to a lower amplitude of the steering wheel angle. This means that to the driver more reaction time is allowed.
Because the system generates longitudinal and lateral accelerations, it works also to allow a smoother transition, with the feeling of more fluid driving experience.