Alternatively, the activation of the stability control system can be triggered by an excess of estimated
sideslip angle, corresponding to a potential vehicle oversteer situation in comparison with the nominal conditions.
Development and demonstration of yaw rate and
sideslip angle control algorithms based on the combination of front / rear and left / right torque vectoring to improve overall vehicle dynamic performance.
It's obvious that minimizing
the sideslip angle improves stability and vehicle safety.
The key to improving the handling and stability in high - speed maneuvers is minimizing
the sideslip angle.
There are three contributors to the slip angle of the wheels:
the sideslip angle of the car, the angular rotation of the car around the up axis (yaw rate) and, for the front wheels, the steering angle.
Due to a limited degree of correction
the sideslip angle is not entirely neutralized by the AHK system; a small delay between steering input and output remains but the delay is very small.
The angle between the car's longitudinal axis and direction of motion is
the sideslip angle.
At low speeds
the sideslip angle is negligible and thus is AHK not active.
The higher the lateral acceleration becomes, the larger
the sideslip angle grows.
It's obvious
the sideslip angle has a very negative impact on the handling of the car throughout the maneuver.
Because of the smaller
sideslip angle in curves the test vehicle equipped with AHK was more stable on corner exits allowing the driver to apply throttle much sooner and gaining higher speeds on the straights.
The effect of the lateral force on
the sideslip angle is much lower for the vehicle with AHK.
The sideslip angle slows down the steering input.
This on its turn increases the lateral acceleration and
sideslip angle, amplifying the steering even further.
In oversteer
the sideslip angle amplifies itself ultimately ending in a spin.
The sideslip angle has a negative impact on the steering response of a vehicle and the steering effort that is required to change direction: If a driver decides to change direction in a curve while the vehicle is subject to oversteer and turns the steering wheel, because of
the sideslip angle the vehicle's longitudinal axis has to cross the current direction of motion first before the vehicle body actually changes direction.
This causes the vehicle to be angled to the actual direction of travel —
the sideslip angle.
The sideslip angle graph indicates the angle the vehicle makes with the current direction of travel.
The reason is again with
the sideslip angle: The car without AHK develops sideslip in a curve which is still present at the exit of the curve.
While doing so, the onset of oversteer is noticeable in good time and the linear increase of
the sideslip angle means that the vehicle remains stable,» noted BMW's release.
Not exact matches
The
sideslip points the vehicle's longitudinal axis towards the inside of the curve, amplifying the steering
angle of the front wheels on the direction of motion.