Anti-slip system ASR (traction control)
Traction control ASR is a logical continuation of the anti-lock braking system ABS and works in tandem with it. ASR is designed to prevent loss of traction of the wheels with the road surface by slipping the driving pair of wheels. It greatly simplifies driving on wet road surfaces.
The first traction control systems appeared in 1979 in BMW cars. And since the mid-1990s, ASR has been included in most passenger cars and SUVs. The essence of the work of ASR today is that driving becomes as easy as possible even on wet pavement or on snow. Special sensors-analyzers fix the speed of rotation of the wheel pairs, and if slippage of one of the wheels is detected, the system automatically reduces the torque coming from the power unit, or immediately reduces the speed by creating additional braking force.
How ASR works
Angular velocity tracking sensors are mounted on the wheels. It is they who read information about the speed of the car and signal the beginning of the slip of one or another wheel. The data is sent to the electronic unit, which compares the available indicators with acceptable ones. In the event that a sharp increase in the speed of one of the wheels in the driving pair is detected, the microprocessor will be forced to send a signal to reduce the torque on this wheel or to slow it down.
At the same time, to reduce traction on different car models, one of the following options is used:
- closing the formation of a spark in a particular cylinder of the power unit;
- reducing the amount of fuel transferred to a specific cylinder;
- throttle valve overlap;
- replacement of the ignition timing.
Along with one of these actions, ASR will brake the wheel to quickly restore good grip on the roadway. For this, actuators operating on electricity and hydraulics are used.
The ASR traction control system relies on the readings of the same sensors as the ABS. In addition, sensors-analyzers of the driver assistance system are used when making sudden braking. Traditionally, all three systems are installed on the vehicle together, complementing each other's work and guaranteeing enhanced traction in all conditions.
Features of the system
However, ASR has some speed limits. For example, to improve the safety of the driver and his passengers, the maximum speed threshold of its operation is strictly defined in the system. Typically, manufacturers set this value at a speed of 40-60 kilometers per hour. Accordingly, if the car moves within this limit, then the ASR will work in full cycle - that is, it will affect the cylinders of the propulsion system and the brake system. In the event that the speed exceeds the factory-set limits, ASR will only be able to reduce the torque on the engine without using the brakes.
FAVORIT MOTORS Group of Companies experts identify three ways in which the traction control system can improve vehicle controllability:
- control of the brakes of the leading pair of wheels (braking of the wheel that began to slip);
- reducing the torque coming from the engine, which, in turn, reduces the speed of rotation of the wheel;
- a combination of the first and second way of working - is considered the most effective way to improve the car's handling on roads with poor coverage.
ASR can be turned off at any time; for this, a special switch is located on the panel in front of the driver or on the steering wheel. The system is enabled or disabled by a special indicator.
Application
The effectiveness of operating vehicles equipped with the ASR traction control system has long been proven. The presence of this system indicates improved vehicle control on difficult road surfaces, as well as when cornering. It allows even a novice driver to feel comfortable on wet or icy surfaces, ensuring traffic safety. Today, the ASR system is included in almost all cars equipped with ABS. A large selection of vehicles of different classes and pricing policies is presented in the showrooms of FAVORIT MOTORS Group. Here you can get acquainted with the latest control systems in practice (sign up for a test drive), and, if necessary, diagnose, adjust or repair the ASR traction control system. The approach to work and reasonable prices make the company's services accessible to every car owner.
