KR102203275B1 - Vehicle Steering Apparatus and Method for Lane Keeping - Google Patents

Abstract

The present invention relates to a vehicle steering control device and a method for maintaining a vehicle lane that supports the vehicle lane maintenance in an elaborate manner without an emotional disparity to a user. The vehicle steering control device for lane maintenance according to the present invention is a previously calculated target requirement. A steering angle calculator configured to calculate a target steering angle based on the rate and the measured yaw rate of the vehicle; A steering torque calculator configured to calculate a target steering angular speed error based on the calculated target steering angle and the measured steering angle of the vehicle, and calculate a target steering torque based on the calculated target steering angular speed error; And a steering control unit for controlling steering of the vehicle according to the target steering torque calculated by the steering torque calculation unit.

Description

Vehicle Steering Apparatus and Method for Lane Keeping}

The present invention relates to a vehicle steering control apparatus and method for maintaining a lane, and more particularly, to an apparatus and method for supporting a vehicle lane maintenance in an elaborate manner without an emotionally heterogeneous feeling to a user.

In general, a lane maintenance support device is a device that detects a lane using image information obtained from a camera sensor and controls a vehicle to prevent a vehicle from leaving a lane based on a result of detecting the lane.

Such a lane maintaining support device may control the vehicle so as not to leave the lane while driving by controlling steering according to the auxiliary steering torque.

In recent years, there is a trend in developing a road center lane maintenance support device that performs lane tracking control by controlling the steering of a vehicle to follow the road center.

However, such a lane keeping support device sets a standard following position to be followed by reflecting the driver's driving tendency, so that it is greatly affected by the road or the state of the driver, or when the vehicle deviates from the standard following position, the standard following position Since the control is rapidly controlled to follow, there is a problem that the driver may feel a sense of difference in such control.

In addition, by controlling the vehicle by calculating the lateral error using the preset target distance, it is not sensitive to the vehicle condition, or compensates only the lateral error of the calculated target trajectory, and is used as a sudden control input when determining the risk of lane departure. There is a problem that excessive response may occur.

Accordingly, in order to solve the above-described problems, a lane maintenance support device has been developed to maintain a consistent control performance even in various driving situations during lane tracking control of a vehicle and to set a variable target distance to minimize control heterogeneity.

However, as such a lane keeping support device uses a direct torque calculation method through yaw rate feedback control, there is a problem in that it is difficult to precisely control feedback on the steering of the vehicle due to this torque calculation method. There is a problem that it causes a sense of heterogeneity.

An object of the present invention is to solve the above problems, and to provide a vehicle steering control apparatus and method for maintaining a lane for controlling steering of a vehicle by calculating a steering torque based on a steering angular velocity.

In order to achieve the above object, the vehicle steering control device for lane maintenance according to an aspect of the present invention includes a steering angle calculation unit that calculates a target steering angle based on a previously calculated target yaw rate and a measured yaw rate of the vehicle, A steering torque calculation unit that calculates a target steering angular speed error based on the target steering angle and the measured steering angle of the vehicle, and calculates a target steering torque based on the calculated target steering angular speed error, and the target steering calculated by the steering torque calculation unit And a steering control unit that controls steering of the vehicle according to the torque, and the steering torque calculation unit calculates a target steering angular velocity error based on the calculated target steering angle and the measured steering angle of the vehicle, and the error calculation unit A feedback steering torque calculation unit that calculates a feedback steering torque by performing PI control on the target steering angular velocity error calculated by and a feed that calculates a feedforward steering torque by performing a feedforward control based on the calculated target steering angle. It includes a forward steering torque calculation unit.

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The error calculating unit is characterized in that it calculates the target steering angular velocity error using the following equation.

(δ _cmd : target steering angle, δ: vehicle steering angle, δ': differential calculation of vehicle steering angle, K _SASAngle : steering angle P gain)

The feedback steering torque calculation unit is characterized in that it calculates the feedback steering torque using the following equation.

(K _{P _ SASSpeed} : Steering _angular speed P gain, K _{I _ SASSpeed} : Steering _angular speed I gain)

The steering angle calculator may include a feed forward steering angle calculator configured to calculate a feed forward steering angle by performing feed forward control based on the input vehicle speed and the previously calculated target yaw rate; And a feedback steering angle calculator configured to calculate a feedback steering angle by performing PI control so that the measured yaw rate of the vehicle follows the previously calculated target yaw rate.

A vehicle steering control method for lane maintenance according to another aspect of the present invention includes calculating a target steering angle based on a previously calculated target yaw rate and a measured yaw rate of the vehicle, and calculating the calculated target steering angle and the measured steering angle of the vehicle. Calculating a target steering angular velocity error based on the calculated target steering angular velocity error, calculating a target steering torque based on the calculated target steering angular velocity error, and controlling the steering of the vehicle according to the calculated target steering torque, wherein the target steering torque is The calculating includes calculating a target steering angular speed error based on the calculated target steering angle and the measured steering angle of the vehicle, performing PI control on the calculated target steering angular speed error to calculate a feedback steering torque, and And calculating a feedforward steering torque by performing feedforward control based on the calculated target steering angle.

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The step of calculating the error is characterized in that the target steering angular velocity error is calculated using the following equation.

(δ _cmd : target steering angle, δ: vehicle steering angle, δ': differential calculation of vehicle steering angle, K _SASAngle : steering angle P gain)

The calculating of the feedback steering torque is characterized in that the feedback steering torque is calculated using the following equation.

(K _{P _ SASSpeed} : Steering _angular speed P gain, K _{I _ SASSpeed} : Steering _angular speed I gain)

The calculating of the target steering angle may include: calculating a feed forward steering angle by performing feed forward control based on the input vehicle speed and the previously calculated target yaw rate; And calculating a feedback steering angle by performing PI control so that the measured yaw rate of the vehicle follows the previously calculated target yaw rate.

According to the present invention, since the steering torque can be calculated based on the steering angular velocity, the steering torque can be determined regardless of the characteristics of the vehicle.

In this way, it is possible to control the steering of the vehicle more robustly and precisely according to the steering torque determined regardless of the characteristics of the vehicle.

In particular, by controlling the steering of the vehicle according to the steering torque determined regardless of the characteristics of the vehicle, it is possible to improve the steering torque response according to the control and reduce the sense of heterogeneity.

1 is a block diagram showing a vehicle steering control apparatus for maintaining a lane according to an embodiment of the present invention.
2 is a diagram showing in detail the target steering angle calculation unit of FIG. 1;
3 is a view showing in detail the target steering torque calculation unit of FIG. 1;
4 is a flowchart showing a vehicle steering control method for maintaining a lane according to an embodiment of the present invention.

The above-described objects and other objects, advantages, and features of the present invention, and methods of achieving them will become apparent with reference to the embodiments described below in detail together with the accompanying drawings.

However, the present invention is not limited to the embodiments disclosed below, but may be implemented in a variety of different forms, and only the following embodiments are for the purpose of the invention to those of ordinary skill in the art, It is only provided to easily inform the composition and effect, and the scope of the present invention is defined by the description of the claims.

Meanwhile, terms used in the present specification are for explaining embodiments and are not intended to limit the present invention. In this specification, the singular form also includes the plural form unless specifically stated in the phrase. As used in the specification, "comprises" and/or "comprising" refers to the presence of one or more other components, steps, actions and/or elements in which the recited component, step, operation and/or element is Or does not preclude addition.

Hereinafter, a vehicle steering control apparatus for maintaining a lane according to an embodiment of the present invention will be described with reference to FIGS. 1 to 3. 1 is a block diagram showing a vehicle steering control apparatus for maintaining a lane according to an embodiment of the present invention.

As shown in FIG. 1, the vehicle steering control apparatus for maintaining a lane according to an embodiment of the present invention includes a target distance calculation unit 100, a target trajectory generation unit 200, a target yaw rate calculation unit 300, A target steering angle calculation unit 400, a target steering torque calculation unit 500, and a steering control unit 600 are included.

The target distance calculation unit 100 calculates a target distance according to the input speed of the vehicle.

For example, the target distance calculating unit 100 first simulates driving of the vehicle while varying the target distance, the speed of the vehicle, and the curvature of the lane. The target distance calculation unit 100 determines the time taken until the vehicle reaches the normal driving state, the lateral offset error between the center of the lane and the vehicle, and the degree of overshoot by this simulation. The target distance calculator 100 sets a target distance for each speed of the vehicle according to the determined result, and approximates the target distance for each speed of the set vehicle using a linear function. The target distance calculator 100 obtains the slope and intercept values of the approximated linear function from the simulation result. The target distance calculation unit 100 applies the obtained slope and intercept values to generate an equation of a straight line using the input variable as the vehicle speed and the output variable as the target distance. The target distance calculating unit 100 calculates a target distance that varies according to the speed of the vehicle by using the generated equation of the straight line.

In addition, as described above, the target distance calculating unit 100 calculates the final target distance by multiplying and calculating a target distance calculated according to the speed of the vehicle by a gain variable according to the curvature.

For example, since a control input faster than a curved road is required for a straight road, the target distance calculation unit 100 considers the effect of the road curvature when calculating the final target distance.

The target trajectory generation unit 200 generates coordinates of a target point separated by the target distance calculated by the target distance calculation unit 100 based on image information input from the camera, and generates a target trajectory to the generated target point. It is created in the form of a trajectory.

For example, the target trajectory generation unit 200 uses a target distance calculated by the target distance calculation unit 100 and varies according to the speed of the vehicle, and the virtual line generated by the vehicle according to an arbitrary offset distance designated from the center of the lane The target trajectory is created as a circle-shaped trajectory to follow.

When the offset distance of the vehicle from the lane center is 0, the target trajectory generating unit 200 generates a target trajectory for following the lane center trajectory.

In addition, when the center point of the lane that is separated by the target distance calculated by the target distance calculation unit 100 from the current position of the vehicle is referred to as the target position, the target trajectory generation unit 200 uses the image information input from the camera. The current position and the heading angle of the vehicle relative to the center of the lane can be calculated, and the target trajectory for reaching the target point on the road can be displayed in a real-time circular profile.

Meanwhile, the target trajectory generation unit 200 calculates the coordinates (x,y) of the target point on the generated target trajectory using the Pythagorean definition. Here, x is the longitudinal distance of the vehicle to the target point, and y is the lateral distance of the vehicle to the target point.

When the coordinates (x,y) of the target point are calculated on the generated target trajectory, the target trajectory generator 200 calculates a curvature value of the target trajectory for following the target point on the generated target trajectory.

To explain the above in more detail, the target trajectory generation unit 200 may obtain vehicle offset, heading angle, and curvature values for each of the left and right lanes of the vehicle using image information input from the camera. have. The target trajectory generation unit 200 may calculate an offset for a lane center, a heading angle, and a lane center curvature value from values obtained using the input image information. The target trajectory generation unit 200 calculates a curvature value of the generated target trajectory by using the calculated offset, heading angle, and curvature values for the center of the lane.

The target yaw rate calculating unit 300 calculates a target yaw rate using the curvature value of the target trajectory calculated by the target trajectory generator 200 and the vehicle speed.

For example, the target yaw rate calculating unit 300 reflects an error due to a lateral slip occurring when the vehicle is turning in the curvature value of the target trajectory calculated by the target trajectory generating unit 200. The curvature value corrected for the error caused by the lateral slip occurring when the vehicle is turning is called the correction target curvature value. The target yaw rate calculation unit 300 calculates an error due to the lateral slip based on the curvature value of the target trajectory, the vehicle speed, and the target distance. The target yaw rate calculation unit 300 calculates a correction target curvature value by correcting the error calculated in the curvature value of the target trajectory. The target yaw rate calculation unit 300 calculates a target yaw rate using the calculated correction target curvature value.

The target steering angle calculation unit 400 calculates a target steering angle using the target yaw rate calculated by the target yaw rate calculation unit 300 and the measured yaw rate of the vehicle.

Hereinafter, the target steering angle calculation unit 400 will be described in more detail with reference to FIG. 2. FIG. 2 is a detailed diagram illustrating a target steering angle calculation unit of FIG. 1.

As shown in FIG. 2, the target steering angle calculation unit 400 includes a feed forward steering angle calculation unit 410 and a feedback steering angle calculation unit 420.

Here, the target yaw rate is a value obtained by comparing and correcting the yaw rate when the vehicle is in a normal driving state and the target yaw rate calculated by the target yaw rate calculator 300. This is to accurately follow the target point by compensating the error of the target yaw rate calculated by the target yaw rate calculation unit 300 when the vehicle is driving on a curvature road by comparing it with the yaw rate in a normal driving state.

For the foregoing, the target steering angle calculation unit 400 compensates by multiplying the error between the target yaw rate calculated by the target yaw rate calculation unit 300 and the yaw rate of the vehicle measured in the normal driving state by multiplying the integral gain. Correct the target yaw rate.

The feed-forward steering angle calculation unit 410 receives the corrected target yaw rate and vehicle speed, performs feed-forward control based on the input target yaw rate and vehicle speed, and outputs a feed-forward steering angle.

For example, the feed forward provision angle calculation unit 410 stores the yaw rate coefficient value of the vehicle corresponding to the steering angle measured for each vehicle speed through the actual vehicle test in a memory in a lookup table method. The feed forward provision angle calculation unit 410 obtains a yaw rate coefficient value that matches the input target yaw rate from the memory, and outputs a steering angle corresponding to the obtained yaw rate coefficient value as a feed forward steering angle.

The feedback steering angle calculation unit 420 receives the measured yaw rate of the vehicle and calculates the feedback steering angle by performing PI (Proportional Integral) control so that the input yaw rate of the vehicle follows the target yaw rate.

The target steering angle calculation unit 400 outputs a target steering angle based on the feed forward steering angle output from the feed forward steering angle calculation unit 410 and the feedback steering angle output from the feedback provision angle calculation unit 420.

The target steering torque calculation unit 500 receives the target steering angle calculated by the target steering angle calculation unit 400 and the measured steering angle of the vehicle to calculate a target steering torque. The target steering torque calculation unit 500 transmits the calculated target steering torque to the steering control unit 600 to control the steering of the vehicle according to the calculated target steering torque.

Hereinafter, the target steering torque calculation unit 500 will be described in more detail with reference to FIG. 3. 3 is a diagram illustrating a target steering torque calculation unit of FIG. 1.

As shown in FIG. 3, the target steering torque calculation unit 500 includes an error calculation unit 510, a feedback steering torque calculation unit 520, and a feedforward steering torque calculation unit 530.

The error calculation unit 510 receives the target steering angle calculated by the target steering angle calculation unit 400 and the measured steering angle of the vehicle, and calculates a target steering angular velocity error based on an error between the two input steering angles. The error calculation unit 510 transmits the calculated target strike angular velocity error to the feedback steering torque calculation unit 520.

To explain the above in more detail, the error calculation unit 510 calculates a target steering angle error by subtracting and calculating the steering angle of the vehicle from the target steering angle. The error calculator 510 calculates a target steering angle speed by multiplying the calculated target steering angle error by the steering angle P gain. The target steering angular speed error is calculated by subtracting the calculated value obtained by differentially calculating the measured steering angle of the vehicle from the calculated target steering angular speed. The error calculation unit 510 transmits the calculated target steering angular velocity error to the feedback steering torque calculation unit 520.

That is, the error calculation unit 510 calculates the target steering angular velocity error as shown in Equation 1.

(δ _cmd : target steering angle, δ: vehicle steering angle, δ': differential calculation of vehicle steering angle, K _SASAngle : steering angle P gain)

The feedback steering torque calculation unit 520 performs PI control on the target steering angular velocity error transmitted from the error calculation unit 510 and outputs the feedback steering torque.

For the foregoing, the feedback steering torque calculation unit 520 first performs a P (Proportional, proportional) control on the target steering angular velocity error transmitted from the error calculation unit 510.

For example, the feedback steering torque calculation unit 520 calculates a first result by multiplying the target steering angular velocity error transmitted from the error calculation unit 510 by the steering angular velocity P gain.

Then, the feedback steering torque calculation unit 520 performs I (Proportional-Integral, Proportional Integration) control on the target steering angular velocity error transmitted from the error calculation unit 510.

For example, the feedback steering torque calculation unit 520 calculates a second result by multiplying the target steering angular velocity error transmitted from the error calculation unit 510 by the steering angular velocity I gain.

Finally, the feedback steering torque calculation unit 520 adds the first result and the second result calculated by performing P control and I control on the target steering angular velocity error transmitted from the error calculation unit 510 to perform feedback steering torque. Yields

That is, the feedback steering torque calculation unit 520 calculates the feedback steering torque by performing the steering angular velocity feedback control as shown in Equation (2).

(K _{P _ SASSpeed} : Steering _angular speed P gain, K _{I _ SASSpeed} : Steering _angular speed I gain)

The feed forward steering torque calculation unit 530 receives the target steering angle calculated by the vehicle speed and target steering angle calculation unit 400, and performs feed forward control based on the input vehicle speed and target steering angle to feed forward. Outputs the steering torque.

For example, the feed forward steering torque calculation unit 530 applies a torque according to the vehicle speed to the steering control unit 600, and measures a steering angle according to the applied torque by the steering control unit 600 controlling the steering of the vehicle. . The measured steering angle and the torque corresponding to the measured steering angle are stored in the memory in a look-a table method. The feed-forward steering torque calculation unit 530 searches for a steering angle of the vehicle that matches the input target steering angle from the memory, obtains a torque corresponding to the searched steering angle from the memory, and outputs it as a feed-forward steering torque.

The target steering torque calculation unit 500 calculates a target steering torque based on the feedback steering torque output from the feedback steering torque calculation unit 520 and the feedforward steering torque output from the feedforward steering torque calculation unit 530. The target steering torque calculation unit 500 transmits the calculated target steering torque to the steering control unit 600.

The steering control unit 600 controls the vehicle to follow the target point according to the virtual target trajectory according to the target steering torque transmitted from the target steering torque calculation unit 500.

As described above, according to the present invention, the steering torque can be calculated based on the steering angular velocity, so that the steering torque can be determined regardless of the characteristics of the vehicle. In this way, it is possible to control the steering of the vehicle more robustly and precisely according to the steering torque determined regardless of the characteristics of the vehicle. In particular, by controlling the steering of the vehicle according to the steering torque determined regardless of the characteristics of the vehicle, it is possible to improve the steering torque response according to the control and reduce the sense of heterogeneity.

Hereinafter, a vehicle steering control method for maintaining a lane according to an embodiment of the present invention will be described with reference to FIG. 4. 4 is a flowchart illustrating a vehicle steering control method for maintaining a lane according to an embodiment of the present invention.

As shown in FIG. 4, as the operation switch is selected to be ON, the vehicle speed is input, and a target distance is calculated according to the input speed (S400).

For example, driving of the vehicle is simulated while varying the target distance, vehicle speed, and curvature of lanes. By this simulation, the time taken until the vehicle reaches the normal driving state, the lateral offset error between the lane center and the vehicle, and the degree of overshoot are determined. According to the determined result, the target distance for each speed of the vehicle is set, and the target distance for each speed of the set vehicle is approximated by a linear function. The slope and intercept values of the approximated linear function are obtained from the simulation results. By applying the obtained slope and intercept values, an equation of a straight line with the input variable as the vehicle speed and the output variable as the target distance is generated. Using the generated linear equation, a target distance that varies according to the vehicle speed is calculated.

In addition, as described above, the final target distance is calculated by multiplying the target distance calculated according to the vehicle speed by a gain variable according to the curvature.

For example, since a straight road requires a faster control input than a curved road, the effect of road curvature is considered when calculating the final target distance.

The coordinates of the target point separated by the calculated target distance based on the image information input from the camera are generated, and the target trajectory to the generated target point is generated in the form of a circle trajectory. The curvature value of the generated target trajectory is calculated (S401).

By using the calculated target distance that varies according to the vehicle speed, a target trajectory for allowing the vehicle to follow a virtual line generated according to an arbitrary offset distance designated from the center of the lane is generated as a circular trajectory.

When the offset distance of the vehicle from the lane center is 0, the target trajectory generating unit 200 generates a target trajectory for following the lane center trajectory.

In addition, if the center point of the lane that is separated by the target distance calculated from the current position of the vehicle is referred to as the target point, the current position of the vehicle and the heading angle of the vehicle to the center of the lane can be calculated using image information input from the camera. In addition, the target trajectory for reaching the target point on the road can be displayed in a real-time circle-shaped profile.

Meanwhile, the coordinates (x,y) of the target point on the generated target trajectory are calculated using the Pythagorean definition. Here, x is the longitudinal distance of the vehicle to the target point, and y is the lateral distance of the vehicle to the target point.

When the coordinates (x,y) of the target point are calculated on the generated target trajectory, the curvature value of the target trajectory for following the target point is calculated on the generated target trajectory.

To explain the above in more detail, it is possible to obtain a vehicle offset, a heading angle, and a curvature value for each of the left and right lanes of the vehicle using image information input from the camera. An offset for a lane center, a heading angle, and a lane center curvature may be calculated from values obtained using the input image information. The curvature value of the generated target trajectory is calculated by using the calculated offset, heading angle, and curvature values for the lane center.

The target yaw rate is calculated using the calculated curvature value of the target trajectory and the vehicle speed (S402).

For example, an error due to lateral slip occurring when the vehicle turns is reflected in the calculated curvature value of the target trajectory. The curvature value corrected for the error caused by the lateral slip occurring when the vehicle is turning is called the correction target curvature value. The error due to lateral slip is calculated based on the curvature value of the target trajectory, the vehicle speed, and the target distance. The correction target curvature value is calculated by correcting the error calculated in the curvature value of the target trajectory. The target yaw rate is calculated using the calculated correction target curvature value.

A target steering angle is calculated using the calculated target yaw rate and the measured yaw rate of the vehicle (S403).

Here, the target yaw rate is a value obtained by comparing the calculated target yaw rate with the yaw rate when the vehicle is in a normal driving state. This is to accurately follow the target point by compensating the error of the target yaw rate calculated when the vehicle is driving on a curvature road by comparing it with the yaw rate in a normal driving state.

For the foregoing, the target yaw rate is corrected by multiplying and compensating the error between the calculated target yaw rate and the measured yaw rate of the vehicle in a normal driving state by multiplying the integral gain.

The corrected target yaw rate and vehicle speed are input, and feed forward control is performed based on the input target yaw rate and vehicle speed to output a feed forward steering angle.

For example, a yaw rate coefficient value of a vehicle corresponding to a steering angle measured for each vehicle speed through an actual vehicle test is stored in a memory in a lookup table method. A yaw rate coefficient value that matches the input target yaw rate is obtained from the memory, and a steering angle corresponding to the obtained yaw rate coefficient value is output as a feedforward steering angle.

The measured yaw rate of the vehicle is input, and the feedback steering angle is calculated by performing PI control so that the input yaw rate of the vehicle follows the target yaw rate.

The target steering angle is calculated based on the output feed forward steering angle and the output feedback steering angle.

A target steering torque is calculated by receiving the calculated target steering angle and the measured steering angle of the vehicle (S404).

For example, the calculated target steering angle and the measured steering angle of the vehicle are input, and a target steering angular velocity error is calculated based on an error between the input two steering angles.

To explain the above in more detail, the target steering angle error is calculated by subtracting and calculating the measured steering angle of the vehicle from the calculated target steering angle. The target steering angle velocity is calculated by multiplying the calculated target steering angle error by the steering angle P gain. The target steering angular speed error is calculated by subtracting the calculated value obtained by differentially calculating the measured steering angle of the vehicle from the calculated target steering angular speed.

PI control is performed on the calculated target steering angular velocity error and feedback steering torque is output.

For the foregoing, P control is performed on the calculated target steering angular speed error.

For example, the first result is calculated by multiplying the calculated target steering angular velocity error by the steering angular velocity P gain.

Then, I control is performed on the calculated target steering angular velocity error.

For example, a second result is calculated by multiplying the calculated target steering angular velocity error by the steering angular velocity I gain.

The feedback steering torque is calculated by adding the first and second results calculated by performing P control and I control on the finally calculated target steering angular velocity error.

In addition, feed-forward control is performed based on the input vehicle speed and target steering angle to output feed-forward steering torque.

For example, a torque according to the amount of speed is applied to the steering controller, and the steering angle according to the applied torque is measured by the steering controller controlling the steering of the vehicle. The measured steering angle and the torque corresponding to the measured steering angle are stored in the memory in a look-a table method. The steering angle of the vehicle matching the input target steering angle is retrieved from the memory, the torque corresponding to the retrieved steering angle is obtained from the memory, and output as a feed forward steering torque.

A target steering torque is calculated based on the output feedback steering torque and the output feedforward steering torque. The calculated target steering torque is transmitted to the steering control unit.

The steering control controls the vehicle to follow the target point according to the virtual target trajectory according to the transmitted target steering torque (S405).

In this way, when the target steering angle is followed, discontinuous tracking does not occur and can be continuously followed. Therefore, since the steering control operates continuously without interruption, it is possible to prevent the driver from feeling disparity.

Although the configuration of the present invention has been described in detail with reference to the preferred embodiment and the accompanying drawings, this is only an example and various modifications are possible within the scope of the technical spirit of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments and should not be defined by the scope of the claims to be described later, as well as the scope and equivalents of the claims.

100: target distance calculation unit 200: target trajectory generation unit
300: target yaw rate calculation unit 400: target steering angle calculation unit
500: target steering torque calculation unit 600: steering control unit

Claims (10)

A steering angle calculator configured to calculate a target steering angle based on the calculated target yaw rate and the measured yaw rate of the vehicle;
A steering torque calculator configured to calculate a target steering angular speed error based on the calculated target steering angle and the measured steering angle of the vehicle, and calculate a target steering torque based on the calculated target steering angular speed error; And
A steering control unit that controls steering of the vehicle according to the target steering torque calculated by the steering torque calculation unit
Including,
The steering torque calculation unit,
An error calculator configured to calculate a target steering angle speed error based on the calculated target steering angle and the measured steering angle of the vehicle;
A feedback steering torque calculator for calculating a feedback steering torque by performing PI control on the target steering angular velocity error calculated by the error calculator; And
Comprising a feedforward steering torque calculator for calculating a feedforward steering torque by performing feedforward control based on the calculated target steering angle
Vehicle steering control device to keep in-lane. delete The method of claim 1, wherein the error calculation unit,
Calculating the target steering angular velocity error using the following equation
Vehicle steering control device for keeping in-lane.

(δ _cmd : target steering angle, δ: vehicle steering angle, δ': differential calculation of vehicle steering angle, K _SASAngle : steering angle P gain) The method of claim 3, wherein the feedback steering torque calculation unit,
Calculating the feedback steering torque using the following equation
Vehicle steering control device for keeping in-lane.

(K _{P _ SASSpeed} : Steering _angular speed P gain, K _{I _ SASSpeed} : Steering _angular speed I gain) The method of claim 1, wherein the steering angle calculation unit,
A feedforward steering angle calculator configured to calculate a feedforward steering angle by performing feedforward control based on the input vehicle speed and the previously calculated target yaw rate; And
And a feedback steering angle calculator configured to calculate a feedback steering angle by performing PI control so that the measured yaw rate of the vehicle follows the previously calculated target yaw rate.
Vehicle steering control device for keeping in-lane. Calculating a target steering angle based on the calculated target yaw rate and the measured yaw rate of the vehicle;
Calculating a target steering angular speed error based on the calculated target steering angle and the measured steering angle of the vehicle, and calculating a target steering torque based on the calculated target steering angular speed error; And
Controlling the steering of the vehicle according to the calculated target steering torque
Including,
The step of calculating the target steering torque,
Calculating a target steering angle velocity error based on the calculated target steering angle and the measured steering angle of the vehicle;
Calculating a feedback steering torque by performing PI control on the calculated target steering angular velocity error; And
Comprising the step of calculating feedforward steering torque by performing feedforward control based on the calculated target steering angle
Vehicle steering control method for maintaining in-lane. delete The method of claim 6, wherein calculating the error comprises:
Calculating the target steering angular velocity error using the following equation
Vehicle steering control method for maintaining in-lane.

(δ _cmd : target steering angle, δ: vehicle steering angle, δ': differential calculation of vehicle steering angle, K _SASAngle : steering angle P gain) The method of claim 8, wherein calculating the feedback steering torque comprises:
Calculating the feedback steering torque using the following equation
Vehicle steering control method for maintaining in-lane.

(K _{P _ SASSpeed} : Steering _angular speed P gain, K _{I _ SASSpeed} : Steering _angular speed I gain) The method of claim 6, wherein calculating the target steering angle,
Calculating a feedforward steering angle by performing feedforward control based on the input vehicle speed and the previously calculated target yaw rate; And
And calculating a feedback steering angle by performing PI control so that the measured yaw rate of the vehicle follows the previously calculated target yaw rate.
Vehicle steering control method for maintaining in-lane.

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