Lane keeping control system for vehicle
A vehicle lane keeping control system calculates a feedforward control amount on the basis of a vehicle traveling path, calculates a first positional deviation amount between a vehicle and a target course at a first forward attention point when the vehicle travels in a straight line to the first forward attention point if a steering torque exceeds a threshold value, calculates a first lateral position feedback control amount, calculates an amount of deviation between an estimated vehicle traveling path and the target course at a second forward attention point remote from the first forward attention point if the first lateral position feedback control amount is lower than the threshold value, calculates a second lateral position feedback control amount, and calculates an electric motor current value by using at least the feedforward control amount and one of the first and second lateral position feedback amounts.
1. A lane keeping control system for a vehicle that sets a target course on which the vehicle travels, calculates a control amount for an electric power steering motor on the basis of at least an amount of deviation between a traveling path of the vehicle and the target course, and controls the vehicle so as to travel along the target course, the system comprising:
a first feedback controller that calculates, as a first positional deviation amount, an amount of deviation between the traveling path of the vehicle and the target course at a predetermined first forward attention point when the vehicle travels in a straight line to the predetermined first forward attention point, and that calculates the control amount for the vehicle to travel along the target course in response to the first positional deviation amount;
a second feedback controller that estimates a traveling path of the vehicle, that calculates, as a second positional deviation amount, an amount of deviation between the estimated traveling path of the vehicle and the target course at a predetermined second forward attention point, and that calculates the control amount for the vehicle to travel along the target course in response to the second positional deviation amount; and
a control selector that selects one of the control amount calculated by the first feedback control unit and the control amount calculated by the second feedback control unit in response to a driver's steering intention.
2. The lane keeping control system for the vehicle according to claim 1 , wherein the second forward attention point is previously set to be remote from the first forward attention point.
3. The lane keeping control system for the vehicle according to claim 1 , wherein
the control selector selects the control amount calculated by the first feedback controller when a steering torque exerted by a driver as the driver's steering intention exceeds a predetermined threshold value; and
the control selector selects the control amount calculated by the second feedback controller when a steering torque exerted by the driver is lower than the predetermined threshold value.
4. The lane keeping control system for the vehicle according to claim 2 , wherein
the control selector selects the control amount calculated by the first feedback controller when a steering torque exerted by a driver as the driver's steering intention exceeds a predetermined threshold value; and
the control selector selects the control amount calculated by the second feedback controller when a steering torque exerted by the driver is lower than the predetermined threshold value.
5. The lane keeping control system for the vehicle according to claim 1 , wherein the control amount includes a control amount that is output to the electric power steering motor and that is necessary for the vehicle to travel along the target course by feedforward control on the basis of a recognized shape of a vehicle traveling road.
6. The lane keeping control system for the vehicle according to claim 2 , wherein the control amount includes a control amount that is output to the electric power steering motor and that is necessary for the vehicle to travel along the target course by feedforward control on the basis of a recognized shape of a vehicle traveling road.
7. The lane keeping control system for the vehicle according to claim 3 , wherein the control amount includes a control amount that is output to the electric power steering motor and that is necessary for the vehicle to travel along the target course by feedforward control on the basis of a recognized shape of a vehicle traveling road.
8. The lane keeping control system for the vehicle according to claim 4 , wherein the control amount includes a control amount that is output to the electric power steering motor and that is necessary for the vehicle to travel along the target course by feedforward control on the basis of a recognized shape of a vehicle traveling road.