Function and composition of vehicle body stability system

The electronic stability system that we usually talk about is available in many car brands, but different manufacturers call it differently. For example, Bosch's body electronic stability system is called ESP, Nissan's vehicle driving dynamics adjustment system VDC, Toyota's vehicle stability control system VSC, Honda's vehicle stability control system VSA, BMW's dynamic stability control system DSC, etc. In a broad sense, the electronic stability control system is called ESC, which is more precise.

What does ESP do?

The electronic stability system mainly controls the longitudinal and lateral stability of the vehicle to ensure that the vehicle drives according to the driver's consciousness. Its basis is the ABS anti-lock braking function. When the tire is about to lock under the braking of the car, the system brakes continuously hundreds of times in one second, which is somewhat similar to the mechanical "point brake". In this way, when the vehicle is fully braked, the tire can still ensure rolling. The effect of rolling friction is better than the sliding friction after locking, and the direction of the vehicle can be controlled. On the other hand, the system will work in conjunction with the engine ECU. When the drive wheel slips, by comparing the speed of each wheel, the electronic system determines whether the drive wheel is slipping, and immediately automatically reduces the throttle intake, reduces the engine speed, thereby reducing the power output, and brakes the slipping drive wheel. In this way, slipping can be reduced and the most appropriate power output between the tire and the ground grip can be maintained. At this time, no matter how much oil is added, the drive wheel will not slip. The system ensures the lateral stability of the vehicle by controlling one or more wheels to brake when it detects understeer or oversteer through signals from the steering angle sensor, lateral acceleration sensor and wheel speed sensor, so as to adjust the vehicle's posture when changing lanes or turning, allowing the vehicle to be more stable and safe when changing lanes or turning.

component

The SP system consists of a control unit and steering sensor (monitoring the steering angle of the steering wheel), wheel sensor (monitoring the speed of each wheel), side slip sensor (monitoring the rotation state of the vehicle body around the vertical axis), lateral acceleration sensor (monitoring the centrifugal force when the car turns), etc.

Sensors: including steering sensors, wheel sensors, side slip sensors, lateral acceleration sensors, steering wheel, accelerator and brake pedal sensors, etc. These sensors are responsible for collecting data on the vehicle body status.

ESP computer: Calculates the data collected by the sensor, calculates the vehicle body status and then compares it with the pre-set data in the memory. When the computer calculates the data that exceeds the pre-stored value in the memory, that is, when the vehicle body is about to lose control or has lost control, it commands the actuator to work to ensure that the vehicle body driving status can meet the driver's intention as much as possible.

Actuator: The actuator of ESP is the brake system of the four wheels. Unlike cars without ESP, the brake system of a car equipped with ESP has a pressure storage function.

Communicator: ESP light on the instrument panel.