A SYSTEM FOR KEEPING AND TRACKING LANE Technical Field

The present invention relates to a system for keeping and tracking lane which makes a vehicle having ESC system to brake such that it will be directed into the lane upon detecting that it approaches the lane line and which is mounted to the vehicle afterwards.

Background of the Invention

Today, different lane tracking assistants are used in order that vehicles can track the lane. One of the methods used in the said lane tracking assistants is to determine the lane lines and the lane, the second one is to determine the location and the need of the vehicle within the lane and another one is to intervene the vehicle dynamics by means of steering or braking. The first method used in the state of the art is related to image processing. Whereas the second method is related to vehicle dynamics.

In lane tracking assistants, aim of intervention is to get the vehicle into the lane again. For this purpose, only the steering angle in the wheels and the braking traction force in the wheels are used as input to the system. The steering angle generated in the wheels independently of the driver, depending on or independently of the steering wheel enables the vehicle to turn towards the center of the lane. In this method, an electric motor mounted to the steering or the steering column or the gears is used. The steering wheel can turn or cannot turn based on the mounting type or the gears structure in between. Whereas in systems operating by selective braking, the moment required for turning the vehicle towards the center of the lane is generated by braking of the rear, the front or both of the wheels facing the center of the lane. This braking transaction is 2

carried out independently of the driver and thus the vehicle should have equipment which can increase the brake pressure in any wheel independently of the driver and the other wheels. In all vehicles having ESC system this equipment is available. it can be intervened in vehicle dynamics over steering in the United States patent documents no. US7765066B2, US8095266B2, US7216023B2, US77U464B2, US6493619B2, US20130231830A1, US7890230B2, US 20110231062A1 and US20110118936A1 whereas they can be intervened over steering or brake in the United States patent document no. US20110015850A1 which are known in the state of the art.

Today, driver support sensor systems attachable to vehicles afterwards are used. These systems are usually mounted to windscreen of a vehicle in some way and sense various factors by watching the way where the vehicle goes through one or more cameras. Various factors sensed during travel are the ones such as lanes, road signs, distance to the front vehicle, relative velocity, surrounding pedestrians. The system warns the driver in a vocal and/or visual and/or tactile way depending on the condition of the factors sensed. The said systems do not perform interventions to affect the vehicle dynamics due to the fact that they are attached to the vehicle afterwards and do not comprise any drive member.

In Figure 1, there is a vehicle schema which is equipped with a lane detection and warning system and an ESC system (A) being used today. Here, the box indicated as environment represents the objects around the vehicle. Besides, lanes in the road can be added to the environment. The lane detection sensor (B) detects the lanes by monitoring the environment. In the event that any danger is detected the driver is warned. The information of steering angle received by the steering angle sensor (E) from the steering is transferred to the CAN system (G). The CAN system (G) transfers the steering angle information received and the data received from the other vehicle sensors (H) located on the vehicle, to the ESC system (A). The ESC system (A) directs the vehicle through brakes by processing the data received. 3

Summary of the Invention

The objective of the present invention is to realize a system for keeping and tracking lane which enables ESC system to detect that the vehicle is under a situation comprising danger such as skidding, sliding by changing the signal of the steering wheel angle proceeding the ESC system in the case of detecting that the vehicle approaches the lane by means of using a sensor system tracking the lane lines in vehicles with ESC system; gets the vehicle into the lane by enabling that the ESC system provided in the vehicle is activated; and gives the ability of keeping lane automatically to the vehicle by being mounted to it afterwards.

Detailed Description of the Invention

"A system for keeping and tracking lane" realized to fulfil the objective of the present invention is shown in the figures attached, in which:

Figure 1 is a schematic view of a system for keeping and tracking lane used in the state of the art.

Figure 2 is a schematic view of the inventive system for keeping and tracking lane.

The components illustrated in the figures are individually numbered, where the numbers refer to the following:

1. System for keeping and tracking lane

2. Sensor unit

3. Decision unit

4. Danger detection unit

5. Intervention unit

A: ESC system

E: Steering angle sensor

G: CAN (Controller area network) system

H: Vehicle sensors 4

Electronic, hydraulic and mechatronic control systems which can change vehicle dynamics by intervening the brake or motor control system of the vehicle independently of the driver will be understood when ESC system (A) (electronic stability control) is stated in the description. The ESC system (A) consists of software having electronic control unit (ECU), hydraulic control unit and electronic control unit.

The inventive system for tracking lane (1) which is used in vehicles having ESC system and mounted to the vehicle afterwards essentially comprises:

- at least one sensor unit (2) which calculates the lanes on the road and also the position of the vehicle within these lanes;

- at least one decision unit (3) which evaluates the possibility of the vehicle going off the lane in the light of the information received from the sensor unit (2) and decides whether there is danger or not;

- at least one danger detection unit (4) which decides in which way the intervention should be realized when there is danger;

- at least one intervention unit (5) which enables the ESC system (A) to detect that the vehicle is out of control and ensures that the ESC system (A) gets the vehicle into the lane again by changing the signal of the steering angle proceeding the ESC system (A) depending on the data received from the detection unit (4).

In the inventive system for tracking lane (1), the decision unit (3) uses the information received from the ESC system (A) and/or also the information received from the other sensors (H) located on the vehicle except the information received from the sensor unit (2). The information received from the other sensors (H) located on the vehicle are gathered on the CAN system (G). The detection unit (4) also decides the intensity of intervention together with the way of intervention using these information. In a preferred embodiment, the decision unit (3) warns the driver when danger is detected. 5

In a preferred embodiment of the invention, the danger detection unit (4) calculates in which way the intervention should be depending on the information received from the sensor unit (2). The danger detection unit (4) decides that the intervention should be to the left when information such as "0" is received from the sensor unit (2), it should be to the right when there is a value different than zero or vice versa. Whereas in another preferred embodiment, the danger detection unit (4) states the amount of intervention in the form of "x radiant per second yaw angle rate" or "x Nm yaw torque" such that a way will be for values higher than zero and another way for values less than zero. In the invention, the danger detection unit (4) can be in any form indicating way and/or magnitude of intervention.

In the inventive system for tracking lane (1), the intervention unit (5) enables the ESC system (A) to detect that the vehicle is out of control by changing the signal of the steering angle proceeding the ESC system (A) of the vehicle in accordance with a data such as signal received from the detection unit (4). Thus, the intervention unit (5) ensures that the ESC system (A) intervenes the vehicle dynamics so that it gets the vehicle into the lane again.

In a preferred embodiment of the invention, the steering angle value passes through the intervention unit (5) and reaches the ESC system (A) over the CAN system (G) of the vehicle. In a preferred embodiment, the steering angle sensor values reaches the intervention unit (5) instead of the CAN system (G).

In case where the intervention unit (5) does not intervene the steering angle in other words the decision unit (3) states that there is no danger, the steering angle sensor (E) measures the steering angle and sends it to the ESC system (A) over the CAN system (G). The ESC system (A) also decides whether the vehicle is under control or not using this angle. In the event that there is danger in the vehicle in other words the decision unit (3) decides on that there is danger in the vehicle by means of the data received from the sensor unit (2), the intervention unit (5) ensures that the signal of the steering angle 6

reaches the CAN system (G) by changing it according to the way and magnitude of intervention received from the detection unit (4). Upon the angle signal changed reaches the CAN system (G), the ESC system (A) intervenes the vehicle. The ESC system (A) decides on that the vehicle skids when the vehicle turns more in comparison to the angle and intervenes such that the vehicle's turning amount will be reduced. The ESC system (A) intervenes the vehicle such that the vehicle's turning amount will be increased when the vehicle turns less in comparison to the angle. Because the ESC system (A) performs its calculations over the steering angle, vehicle dynamics can be intervened.

In a preferred embodiment of the invention, the intervention unit (5) changes the steering angle signal to the left when it is decided that there is danger and the way of intervention is to the left. The ESC system (A) evaluates this case such that the vehicle wants to turn left but it cannot and ensures that the vehicle goes to the left and thus gets into the lane by braking the left rear wheel of the vehicle. The ESC system (A) determines that the vehicle wants to turn left but it cannot turn on the grounds that the yaw angle does not change. The ESC system (A) intervention to the vehicle varies by the manufacturer and the version of the ESC system. In a preferred embodiment of the invention, the intervention unit (5) changes the steering angle signal to the right (or left) when it is decided that there is danger and the way of intervention is to the right (or left). The ESC system (A) evaluates this case such that the vehicle wants to turn right (or left) but it cannot and ensures that the vehicle goes to the right (or left) and thus gets into the lane by braking the right (or left) rear wheel of the vehicle. The ESC system (A) determines that the vehicle wants to turn right (or left) but it cannot turn on the grounds that the yaw angle does not change. The ESC system (A) intervention to the vehicle varies by the manufacturer and the version of the ESC system. In a preferred embodiment of the invention, the intervention unit (5) uses the yaw angle required and/or the yaw torque variables required except the left right turn signals in the event that there is danger. In a preferred embodiment of the invention. 7

the intervention unit (5) can send data to the CAN system (G) and also withdraw information such as information of yaw, etc. from the CAN system (G).

In the inventive system for tracking lane (1), the steering angle signal is cut before it reaches the CAN system (G) and transmitted to the CAN system (G) upon being changed where necessary by the intervention unit (5). The inventive system for tracking lane (1) gives the ability of keeping lane automatically to the vehicles with ESC system (A) by being mounted to them afterwards.

It is possible to develop various embodiments of the inventive system for keeping and tracking lane (1), it cannot be limited to examples disclosed herein and it is essentially according to claims.