History and purpose of the system
In 1985 at the exhibition Amsterdam Motor Show on the stand of the Bavarian concern BMW the model M5 was blushed. In addition to the designer and powerful engine, the Germans demonstrated another technical "thing". The steering wheel in this M5 could be turned with one finger in the parking lot, but also at high speed, the accuracy of the control did not disappear. Servotronic was thus presented to the general public.
The purpose of the service is to regulate the increase in rotation of the steering wheel according to the speed of traffic, thus ensuring comfortable driving in any situation.
Servotronic is a relatively recent invention. Since this is a steering control system, this option is only possible if there is a hydro-or electrical power steering system.
The Servotronic system has analogues that perform similar functions, but are implemented at the expense of other mechanisms. Under the name Servotronic the system is installed on BMW, Audi, Volkswagen, Volvo and Porsche cars. The trademark is owned by the American firm AM General corp.
Device and service principle
It is possible to divide the system into two parts: informing and implementing. The Servotronic control unit is a connecting link.
The system uses input sensors to obtain information. These include the steering amplifier sensor and the steering wheel angle sensor for vehicles equipped with ESP. These devices determine the rudder position relative to the angle of the wheels of the motor vehicle. In rum, the above sensors are used by the Hall sensor, which informs about the crankshaft position. The speedometer sensor signals the vehicle's speed.
Information received from all sensors is transmitted as a signal to the control unit that processes the data and sets the behavior of the actuating mechanism.
The executive system consists of a reverse cell, which has a piston in it. The piston is connected to the gold-mining steering. The chamber's design includes an electromagnetic valve. This is controlled by the Servotronic control unit.
To turn the wheels from one extreme position to the opposite, rotate the steering wheel by 360 degrees.
When steering the rudder, the gilk shall omit the liquid to the cylinder of the GTP, which affects the steering mechanism of the wheel. At the same time, the control unit, based on the data from the sensors, opens an electromagnetic valve, and the liquid fills the feedback chamber. As a result, the pressure in the hydraulic amplifier is dropping, the piston of the reverse action blocks the gold and the effort on the steering wheel increases.
The force is controlled by the valve, depending on the speed. The higher the speed, the more the valve is open and vice versa. In the parking lot, the reverse action camera is completely closed and the steering wheel is rotated as easy as possible.
Servotronic system taxes
In addition to Cervoke, there are other systems that make it possible to ensure comfortable office in different situations. For example, active steering (AFS-ActiveFront Steering). The system accelerates the reaction of the vehicle to the steering wheel. In order to turn the wheels from one extreme position to the opposite, it is enough to rotate the steering angle by 360 degrees.
Already today there are a concept car that does not have a mechanical link between the steering wheel and its wheels
The active management system is operated by a planetary reductor equipped with an electric motor. The gear adjuster to the steering shaft and the control unit command changes the gear ratio between the steering wheel and the wheels of the vehicle.
AFS receives data from sensors installed on the motor vehicle: from the steering wheel angle sensor; sensor of aggregate angle of turn and speedometer.
The gear ratio is increasing at high speeds. The point is that, with rapid rotation, the friction is reduced and the wheels turn more easily. At a low speed, such as parking, the steering wheel is much more difficult because of the increased friction. The system analyts sensor data and selects the appropriate gear ratio for each situation.
There are already a concept car that does not have a mechanical steering. It is more accurate to say that there is no mechanical linkage between the steering wheel and its wheels. Electric drives are used to perform the rotation and operate under the control of the computer system.
The car is fitted with the normal steering wheel, but its position is monitored by the sensor. Also, a lot of sensors record the angle of the wheels, the speed of motion, the position of the crankshaft. The information is transmitted to the control unit and to the wheels.
The system has enormous advantages because in critical situations it can react faster than the driver. For example, when a vehicle is skidered, the system will be able to assess the situation in time thanks to the sensors and turn the wheels on its own to the desired angle. However, in the near future, the serial production of such systems is impossible, since the legislation prohibits the production of cars that lose control over the failure of electronic systems-mechanical management should be obligatory.
