Lane Keeping Assist (LKA)
Lane Keep Assist (LKA) is a driver assistance system that supports the driver to maintain the vehicle within its driving lane by counter steering. It hereby aims to prevent the vehicle from departing its lane when the vehicle unintentionally drifts towards the lane lines when the driver is not paying attention to avoid a potentially dangerous situation.
The perception system with camera provides information on detected lines including the line type, distance from centre of host vehicle to line edge, estimated curvature of line, angle between host vehicle direction and detected lane's direction, and if the detected line is valid for use in an LKA feature. When "Lane Keeping Assist" is activated, the system working speed range is from 60-150 kph.
The system is disabled when one of the following conditions are met:
- Vehicle speed is less than 60 kph or exceeds 150 kph;
- Driver turns the indicator on during lane departure;
- ESC detects an unstable mode of the vehicle
- System has lost lane marking;
- Another active safety system of the vehicle is in intervention;
- Lane width exceeds 4.5 m or is below 2.5 m - still active when vehicle is getting closer to the lane or lane is smaller than 2.5 m, system changes to standby mode;
- Vehicle crosses latest warning line;
- Driver intervenes and steers the vehicle back into the lane; or
- System failure occurs.
When the "Lane Keeping Assist" (LKA) is activated, ADAS receives information on the following:
- An activated turn signal;
- The yaw rate;
- The vehicle speed;
- The gear engaged;
- The steering wheel angle;
- The status of the hands-on sensor*;
- The door status (open/closed)*;
- The tire pressure monitoring system*; and
- The status of the trailer module*.
*) additional information on "Lane Departure Warning (LDW)"
The camera provides information on the lane markings and the position of the vehicle within the lane. If the ADAS detects the vehicle approaching one of the lane marking, the color of the lane limit changes to red, and at the same time a command is issued to the Electrical Power Steering for a haptic warning. The system issues a warning message via the Multimedia Head Unit (MHU). In the event that the vehicle drifts out of the lane, the system initiates corrective steering movements to keep the vehicle in the lane.
System Architecture
IDB - Integrated Dynamic Brake
BCM - Body Control Module
HOD sensor - Hands-on-wheel-sensor
EPS - Electrical Power Steering
PWT - Powertrain
MHU - Multimedia Head Unit (MHU)/Multimedia Display Unit (MDU)/HMI
EPS - Electrical Power Steering
TPMS - Tire Pressure Monitoring System
HMI state flow