Electronic stability control system (Opel Insignia A)

The stability control system helps maintain vehicle stability during aggressive maneuvering. Vehicle yaw is the acceleration of the vehicle body rotation around the vertical axis. The stability control system is activated by the electronic brake control unit when it detects a discrepancy between the desired angular velocity and the actual yaw value measured by the corresponding sensor.

The desired value of angular acceleration is calculated by the electronic brake control unit using the following input data:

• Signal from the steering wheel angle sensor.
• Vehicle speed.
• Longitudinal acceleration.

The difference between the desired angular acceleration and the actual yaw of the car is the value needed to measure oversteer or understeer. When such a difference is detected, the electronic brake control unit attempts to stabilize the movement by braking one or more wheels. The degree of pressure on the brake pedal is constantly changing, so the pressure in the brake circuits is also constantly adjusted. In addition, if necessary to slow the car down to maintain directional stability, the engine torque can be reduced.

Activation of the stability control system usually occurs during sharp turns during aggressive driving. When braking while the system is activated, the brake pedal may pulsate.

The traction control system can be manually switched off or on by pressing the traction control switch for 5 seconds.

(Material copied from this portal: opelbook.ru)