The key technologies of lane keeping system (LKS) include the lane recognition, lane model construction, system identification, vehicular dynamic parameters estimation, lane keeping control algorithm, and active steering control algorithm. The LKS is designed to keep the vehicle in the lane center automatically, and system function needs to be acted by driver steering torque. The lane model is used to calculate the relationships between vehicle and lane that to be the control input, and the frequency response of the dynamic model of the control plant is used to design the desired gain margin and phase margin of LKS. And the LKS system also take the driver intervention machine to decide the lane keeping function works or not. If the lane keeping function works, the controller can generate the steering command to the EPS system. Finally the vehicle will track the desired path by the steering command calculated from LKS controller.

1. Multiple order polynomial lane model
2. Radius of curve ≥ 150 m
3. Vehicle speed: 20 ~ 120 kph
4. Operational limits: lateral acceleration≤0.3g, : lateral Jerk≤5m/s3, longitudinal deceleration ≤ 0.3 g

The LKS can be used in vehicles equipped with EPS system which integrates active steering control function.

Domestic manufacturers have established lane departure warning (LDW) and EPS technologies. The key technologies of LKS developed by ARTC, such as system integration, road model construction, vehicular parameters estimation, system identification, system control logic design, can make the companies have capabilities of system integration and upgrade their products to active safety systems to improve competitiveness.