What is Electronic Stability Control (ESP,ESC)

The Electronic Stability Control, or ESC acronym for Electronic Stability Control, also known by trade names of ESP from German Elektronisches Stabilitätsprogramm and VDC Vehicle Dynamic Control is an active safety system for motor vehicles.

It is a system for controlling the stability of the car, acting under heels, regulating engine power and braking individual wheels in different ways so as to re-establish the structure of the car. This device is effective in correcting both situations any oversteer or understeer, which can occur in case of wrong setting of a curve, and in cases of sudden deviation of trajectory and avoid skidding of the vehicle. Recently, some commercial vehicles equipped with Adaptive ESP, able to change the type of intervention according to the weight of the vehicle and then, when the cargo is transported. This is an evolution of the ESP, based on MEMS products from STMicroelectronics, a technology whose function was to stop the brakes before a block and wheel slippage.

The ESP uses some information coming out of the vehicle itself in motion: 4 speed sensors (one per wheel) built into the wheel hub that communicate to the control of the speed of each wheel. A steering angle sensor, which communicates to the central position of the steering wheel and then the intentions of the driver. 3 accelerometers (one for each spatial axis) normally located at the center of the car, tell the controller the forces acting on the car. Some sensors are already on the engine management as the throttle position sensor on the brake and accelerator.

The unit is involved with the way the engine (reducing torque) and the individual brake calipers, correcting the momentum of the car. Especially in the case of understeer, braking the rear wheel brakes intervene inside the curve, creating a moment opposite to the crush, while in case of oversteer is braking the front wheel to the outer curve, generating more and opposite movement.

This system is generally associated with the traction control system (TCS) and all'antibloccaggio (ABS), as in fact complementary in maintaining the stability of the vehicle under various driving conditions, as more assertive when braking in curves, in the wet or surfaces with low grip and traction when braking with different wheels.