.:: Types of Electronics Stability Control ::.

• ABS-based Electronic Stability Control- The majority of electronic stability control systems are designed to work off the automobile's Anti-lock Braking System(ABS) because it is relatively easy for automotive engineers to implement. The ESC computer monitors driver's input into the vehicle's steering wheel, accelerator, and brakes through a series of sensors for data collection. When a significant turn or emergency maneuver is initiated the ESC system activates on the incoming sensor data, communicating through the braking system to minimize yaw effects by transferring anti-lock brake power onto one or more wheels. This computer-controlled braking works within milliseconds to stabilize the vehicle turning.

• Differential Electronic Stability Control- Beyond the path of ABS-based ESC, a technology by Mitsubishi named Super Active Yaw Control wires the vehicle's Electronic Control Unit (ECU) into a limited-slip differential run through a set of planetary gears. Under high yaw, the ECU will instruct the Active Yaw Control differential to apply greater torque to the outer wheels while decreasing torque of the inner wheels thereby inducing a stable turn. The all-wheel drive Mitsubishi Lancer Evolution GSR will be the first vehicle Mitsubishi has sold with Active Yaw Control inside the United States market. Another system very much similar to Mitsubishi's unit appeared on the Honda Prelude but has not yet proceeded through further development.

.:: Operation of Electronic Stability Control ::.

A driver loses control when the vehicle goes in a direction different from the one indicated by the position of the steering wheel. This typically occurs when a driver tries to turn very hard (swerve) or to turn on a slippery road. Then the vehicle may understeer or oversteer.

When a vehicle understeers it turns less than the driver intended and continues in a forward direction because the front wheels have insufficient traction. When it oversteers it turns more than the driver intended because the rear end is spinning or sliding out.

ESC uses sensors in the car (wheel speed sensors, steering wheel position sensors, yaw sensors, etc.) to determine which direction the driver wants the car to go, and compares that to which way the car is actually going. If the system senses that a skid is imminent or has already started -- in other words, that the car is not going in the direction the driver is telling it to go -- it can apply the brakes on individual wheels to bring the car back under control. Because the system can brake individual wheels, whereas the driver can only brake all four wheels at once, ESC can recover from skids that a human driver can't.

If my car has electronic stability control, does that mean I can't lose control of my car??

NO! Even with ESC, it is still possible to lose control of the car.

Excessive speed, slick roads, and excessively worn or improperly inflated tires are all factors that can reduce ESC's effectiveness.

.:: Example On the Electronic Stability Control ::.

     Example 1  where the side to side comparison about this system

    With the ESC /ESP as the basic , more company was doing the research on their own system on the stability control;

 

http://www.aa1car.com/library/stability_control.htm 

      Some components on the Merc ECS

.:: Introduction ::.

      In 1995, automobile manufacturers introduced ESC systems. Mercedes-Benz provide by Bosch,first implement on W140 S-Class model. On the same year BMW also follow the Mercedes but the ESC is provided by Bosch and ITT Automotive (later acquired by Continental Automotive Systems).

Mercedes Benz W140 S-class With ESC 
http://www.automobilesdeluxe.tv/tag/w140/ 




      Volvo Cars began to offer their version of ESC called DSTC (Dynamic Stability and Traction Control)(1998) on the S80. Toyota's Vehicle Stability Control system (in 2004, a preventive system called VDIM) appeared on the Crown Majesta(1995) and more company investigated and developed their own systems on ECS.

      During a moose test (swerving to avoid an obstacle) which became famous in Germany as "the Elk test" the Swedish journalist Robert Collin of Teknikens Värld (World of Technology) in October 1997 rolled a Mercedes A-Class (without ESC) at 78 km/h. Because Mercedes-Benz promotes a reputation for safety, they recalled and retrofitted 130,000 A-Class cars with ESC which produced a significant reduction in crashes and the number of vehicles with ESC rose. Nowadays virtually all branded vehicles have made ESC standard on all vehicles, and the number of models with ESC continues to increase. 

      Ford and Toyota announced that all their North American vehicles would be equipped with ESC standard by the end of 2009 (it was standard on Toyota SUVs as of 2004, and after the 2011 model-year, All Lexus, Toyota, and Scion vehicles have ESC; the latest to get it was the 2011 model-year Scion tC).But until November 2010, Ford still sell vehicles without ECS in North America.

      The NHTSA ( National Highway Traffic Safety Administration )  requires all passenger vehicles to be equipped with ESC by 2012 and estimates it will prevent 5,300-9,600 annual fatalities once all passenger vehicles are equipped with the system.