KR20220064012A - Steering control apparatus and method of steer by wire system - Google Patents

Abstract

Disclosed are a steering control apparatus and method of a SBW system. The steering control apparatus of a SBW system of the present invention comprises: a steering intervention determination unit which determines whether a position control error amount of a steering wheel satisfies a predetermined driver steering intervention determination condition in an autonomous driving mode and cancels the autonomous driving mode according to the determination result; a reaction force control unit which variably controls reaction force of the steering wheel based on the position control error amount according to the determination result of the steering intervention determination unit; and an actuator output control unit which variably controls a steering wheel of a vehicle wheel based on the position control error amount according to the determination result of the steering intervention determination unit. The steering control apparatus accurately determines steering intervention of a driver during autonomous driving and shifts a steering mode.

Description

STEERING CONTROL APPARATUS AND METHOD OF STEER BY WIRE SYSTEM

The present invention relates to an apparatus and method for controlling a steering of an SBW system, and more particularly, to an apparatus and method for controlling a steering of an SBW system by accurately determining a driver's steering intervention during autonomous driving and transitioning a steering mode without feeling heterogeneous.

The SBW (STEER BY WIRE) system is a steering system that separates the mechanical connection between the steering wheel and the driving wheel of the vehicle. The SBW system receives the steering wheel rotation signal through the electronic control unit (ECU), and based on the input rotation signal, operates the steering assist motor connected to the driving wheel to steer the vehicle.

The SBW system has advantages such as increasing the freedom of layout according to the steering system configuration, improving fuel efficiency, and removing the disturbance from the reverse input from the wheel by removing the mechanical connection structure of the existing steering system.

On the other hand, if an emergency situation such as a risk of a collision or other accident suddenly occurs during autonomous driving, the vehicle must avoid the emergency situation through vehicle speed or steering control. In order to avoid an emergency situation, it is effective to reduce the vehicle speed, but the driver's steering may be required if necessary. For example, if the autonomous driving system fails, the driver's steering must be taken into account because the vehicle may be driven differently from the driver's intention.

However, since the SBW system does not have a column torque sensor, it is difficult to determine the driver's steering intervention. There were insufficient aspects to accurately determine the intervention.

The background technology of the present invention is disclosed in 'Vehicle control apparatus and method' of Korean Patent Application Laid-Open No. 10-2020-0023825 (2020.03.06).

The present invention was created to improve the above problems, and an object according to an aspect of the present invention is to accurately determine the steering intervention of the driver during autonomous driving and to provide a steering control apparatus and method of an SBW system for transitioning the steering mode without feeling heterogeneous. is to provide

The steering control apparatus of the SBW system according to an aspect of the present invention determines whether an error amount of a position control error of a steering wheel in an autonomous driving mode satisfies a preset driver steering intervention determination condition, and determines whether the autonomous driving mode is canceled according to the determination result. wealth; a reaction force control unit for variably controlling the reaction force of the steering wheel based on the position control error amount according to the determination result of the steering intervention determination unit; and an actuator output adjusting unit for variably controlling the steering angle of the wheel based on the position control error amount according to the determination result of the steering intervention determination unit.

The steering intervention determining unit of the present invention comprises: a position control error amount detection unit for detecting the amount of the position control error; and a steering mode determining unit configured to cancel the autonomous driving mode by determining whether to intervene in the driver according to whether the holding time for which the amount of the position control error is maintained satisfies the condition for determining the driver's steering intervention.

The steering mode determining unit of the present invention is characterized in that when the position control error amount is included in a preset reference range and is maintained for a preset time in a state included in the reference range, it is determined that the driver's steering intervention is determined.

Each of the reference range and the set time of the present invention is characterized in that a plurality are provided to match each other one-to-one.

The set time of the present invention is characterized in that it decreases as the reference range increases.

The steering mode determining unit of the present invention is characterized in that it further comprises a position control error amount filter for filtering the position control error amount less than a preset minimum threshold value.

The reaction force adjusting unit of the present invention is characterized in that it variably controls the reaction force of the steering wheel according to the amount of position control error at the time when the driver's steering intervention determination condition is satisfied.

The reaction force control unit of the present invention reduces the position control output for maintaining the steering angle of the steering wheel at 0 degrees and increases the reaction force control output of the steering wheel according to the amount of position control error at the time when the driver's steering intervention determination condition is satisfied characterized in that

The reaction force adjusting unit of the present invention is characterized in that it adjusts the variable speed of the reaction force of the steering wheel according to the amount of position control error when the driver's steering intervention determination condition is satisfied.

The variable speed of the reaction force of the steering wheel according to the present invention is characterized in that it is proportional to the amount of position control error when the driver's steering intervention determination condition is satisfied.

The wheel steering angle adjusting unit of the present invention is characterized in that it variably controls the steering angle of the wheel according to an amount of a position control error when the driver's steering intervention determination condition is satisfied.

The wheel steering angle adjusting unit of the present invention reduces the control output according to the commanded steering angle of the autonomous driving system according to the amount of position control error at the time when the driver's steering intervention determination condition is satisfied, and increases the actuator control output according to the commanded steering angle of the reaction force control module. characterized by increasing it.

The wheel steering angle adjusting unit of the present invention is characterized in that it adjusts the steering angle variable speed of the wheel according to the amount of position control error when the driver's steering intervention determination condition is satisfied.

The variable speed of the steering angle of the wheel according to the present invention is characterized in that it is proportional to the amount of position control error when the driver's steering intervention determination condition is satisfied.

A steering control method of an SBW system according to an aspect of the present invention includes the steps of determining whether an error amount of a position control error of a steering wheel in an autonomous driving mode satisfies a preset driver steering intervention determination condition, and canceling the autonomous driving mode according to the determination result; variably controlling the reaction force of the steering wheel based on the position control error amount according to a result of determining whether the driver's steering intervention determination condition is satisfied; and variably controlling the steering angle of the wheel based on the position control error amount according to a result of determining whether the driver's steering intervention determination condition is satisfied.

In the step of canceling the autonomous driving mode of the present invention, the amount of the position control error is detected, and whether the driver's steering intervention It is characterized by canceling the autonomous driving mode.

In the step of canceling the autonomous driving mode of the present invention, if the position control error amount is included in a preset reference range and maintained for a preset time in a state included in the reference range, it is determined that the driver's steering intervention is determined. do it with

Each of the reference range and the set time of the present invention is characterized in that a plurality are provided to match each other one-to-one.

The set time of the present invention is characterized in that it decreases as the reference range increases.

The step of canceling the autonomous driving mode of the present invention is characterized in that it further comprises the step of filtering the position control error amount less than a preset minimum threshold value.

The step of variably controlling the reaction force of the steering wheel according to the present invention is characterized in that the reaction force of the steering wheel is variably controlled according to an amount of a position control error when the driver's steering intervention determination condition is satisfied.

In the step of variably controlling the reaction force of the steering wheel according to the present invention, the position control output for maintaining the steering angle of the steering wheel at 0 degrees is reduced according to the amount of position control error at the time when the driver's steering intervention determination condition is satisfied, and the steering wheel It is characterized in that the reaction force control output is increased.

The step of variably controlling the reaction force of the steering wheel according to the present invention is characterized in that the variable speed of the reaction force of the steering wheel is adjusted according to an amount of a position control error when the driver's steering intervention determination condition is satisfied.

The variable speed of the reaction force of the steering wheel according to the present invention is characterized in that it is proportional to the amount of position control error when the driver's steering intervention determination condition is satisfied.

The step of variably controlling the steering angle of the wheel according to the present invention is characterized in that the steering angle of the wheel is variably controlled according to an amount of a position control error when the driver's steering intervention determination condition is satisfied.

In the step of variably controlling the steering angle of the wheel of the present invention, the control output according to the commanded steering angle of the autonomous driving system is reduced according to the amount of position control error at the time when the driver's steering intervention determination condition is satisfied, and the control output is adjusted to the commanded steering angle of the reaction force control module. It is characterized in that the actuator control output is increased accordingly.

The variable control of the steering angle of the wheel according to the present invention is characterized in that the variable speed of the steering angle of the wheel is adjusted according to an amount of a position control error when the driver's steering intervention determination condition is satisfied.

The variable speed of the steering angle of the wheel according to the present invention is characterized in that it is proportional to the amount of position control error when the driver's steering intervention determination condition is satisfied.

An apparatus and method for controlling a steering of an SBW system according to an aspect of the present invention accurately determine the steering intervention of a driver during autonomous driving and thereby transition the steering mode without any heterogeneity.

According to another aspect of the present invention, an apparatus and method for controlling a steering of an SBW system may provide a transitional steering feel optimized for a driver's steering intervention situation by variably controlling a reaction force of a steering wheel according to a driver's steering intervention situation.

The steering control apparatus and method of the SBW system according to another aspect of the present invention can accurately determine the steering intention of the driver and immediately transition the steering mode when the driver's sudden steering is required due to the occurrence of an emergency during autonomous driving. safety can be ensured.

1 is a block diagram of a steering control apparatus of an SBW system according to an embodiment of the present invention.
FIG. 2 is a block diagram of the steering intervention determination unit of FIG. 1 .
3 is a flowchart of a steering control method of an SBW system according to an embodiment of the present invention.

Hereinafter, an apparatus and method for controlling a steering of an SBW system according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. In this process, the thickness of the lines or the size of the components shown in the drawings may be exaggerated for clarity and convenience of explanation. In addition, the terms to be described later are terms defined in consideration of functions in the present invention, which may vary according to intentions or customs of users and operators. Therefore, definitions of these terms should be made based on the content throughout this specification.

Implementations described herein may be implemented in, for example, a method or process, an apparatus, a software program, a data stream, or a signal. Although discussed only in the context of a single form of implementation (eg, discussed only as a method), implementations of the discussed features may also be implemented in other forms (eg, as an apparatus or program). The apparatus may be implemented in suitable hardware, software and firmware, and the like. A method may be implemented in an apparatus such as, for example, a processor, which generally refers to a computer, a microprocessor, a processing device, including an integrated circuit or programmable logic device, and the like. Processors also include communication devices such as computers, cell phones, portable/personal digital assistants (“PDA”) and other devices that facilitate communication of information between end-users.

1 is a block diagram of a steering control apparatus of an SBW system according to an embodiment of the present invention, and FIG. 2 is a block diagram of the steering intervention determination unit of FIG. 1 .

Referring to FIG. 1 , the steering control device of the SBW system according to an embodiment of the present invention includes a vehicle speed sensor 10 , a steering angle sensor 20 , a steering wheel control module 30 , an actuator control module 40 , It includes a steering intervention determining unit 50 , an autonomous driving system 60 , a reaction force adjusting unit 70 , and a wheel steering angle adjusting unit 80 .

The vehicle speed sensor 10 detects the vehicle speed of the autonomous vehicle.

The steering angle sensing unit 20 detects a steering angle of a steering wheel of the autonomous vehicle.

The autonomous driving system 60 generates a command steering angle for autonomous driving control of the vehicle based on information detected by various sensors in the autonomous driving mode, and transmits the generated command steering angle to the actuator control module 40 . Since a person skilled in the art can easily perform autonomous driving control by the autonomous driving system 60 based on various types of information, a detailed description thereof will be omitted herein.

In the present embodiment, the SBW (STEER BY WIRE) system is a steering system that separates the mechanical connection between the steering wheel and the driving wheels of the vehicle, and includes a steering wheel control module 30 and an actuator control module 40 .

The steering wheel control module 30 provides an appropriate reaction force to the driver through the reaction force control motor when steering the driver, thereby providing the driver with a natural steering feel (restoration, damping, road surface feedback, and vehicle load).

The steering wheel control module 30 may detect a yaw rate and a side slip angle by applying a vehicle speed and a steering angle to a vehicle modeling equation, and calculate a rack force of the vehicle through these. In addition, the steering wheel control module 30 provides a natural reaction force to the driver by applying an appropriate ratio to the rack force.

In addition, the steering wheel control module 30 multiplies the error amount generated during position control of the actuator control module 40 by an appropriate ratio so that the driver can feel the road feeling of the road surface, and the actual steering wheel control module ( 30), a more dynamic steering feel is provided to the driver by adjusting the level to be applied to the reaction force control motor (not shown) and then performing the reaction force control.

Meanwhile, in the driver steering mode, when the steering angle of the steering wheel is sensed by the steering angle sensing unit 20 , the steering wheel control module 30 generates a command steering angle according to the steering angle and transmits the generated command steering angle to the actuator control module 40 . transmit

In the autonomous driving mode, the steering wheel control module 30 does not need to generate a reaction force to the driver. Accordingly, the steering wheel control module 30 position-controls the steering angle at a reference angle, that is, 0 degrees through the reaction force control motor. That is, the steering wheel control module 30 maintains the steering wheel at 0 degrees.

Meanwhile, in the driver steering mode, the actuator control module 40 drives the rack bar according to the command steering angle received from the steering wheel control module 30 .

On the other hand, in the autonomous driving mode, the actuator control module 40 controls the actuator motor according to the command steering angle of the wheel received from the autonomous driving system 60 to drive the vehicle in the direction set by the autonomous driving system 60 .

Here, a steering force actuator (SFA) may be employed as the steering wheel control module 30 , and a road wheel actuator (RWA) may be employed as the actuator control module 40 .

That is, in the autonomous driving mode, the steering wheel control module 30 maintains the steering angle of the steering wheel at 0 degrees through the reaction force control motor, and the actuator control module 40 receives the command steering angle of the wheel received from the autonomous driving system 60 . control the vehicle driving direction.

As described above, the steering intervention determination unit 50 determines whether the amount of error in position control of the steering wheel in the autonomous driving mode satisfies a preset driver steering intervention determination condition, and cancels the autonomous driving mode according to the determination result.

When the driver intervenes in the autonomous driving mode, the steering wheel control module 30 increases the amount of current for controlling the reaction force control motor in order to maintain the steering wheel at 0 degrees. That is, even if the driver intervenes in the steering, the actual steering wheel maintains the 0 degree state. When the driver intervenes, the amount of current for maintaining the steering wheel in the 0 degree state further increases. Based on the amount, it is determined whether the current steering of the steering wheel is a steering intervention according to the driver's will or an unintentional steering intervention by the driver.

For example, when the driver intentionally intervenes in steering in an emergency situation, the amount of position control error is relatively large.

Conversely, when the driver does not intentionally intervene, for example, when the driver unintentionally closes or moves the steering wheel indoors, the amount of position control error is relatively small.

Accordingly, the steering intervention determination unit 50 determines whether the driver is involved in steering according to the amount of position control error output from the steering wheel control module 30 in the autonomous driving mode, and cancels the autonomous driving mode according to the determination result.

Referring to FIG. 2 , the steering intervention determination unit 50 includes a position control error amount filter unit 51 , a position control error amount detection unit 52 , and a steering mode determination unit 53 .

The position control error amount filter unit 51 filters the position control error amount that is less than or equal to a preset minimum threshold value input from the steering wheel control module 30 . The minimum threshold is a typical position control error amount that occurs in the case of unintentional steering intervention by the driver, for example, a steering wheel touch.

If the driver's unintentional steering intervention occurs, the amount of positioning air may increase. When the steering wheel is touched while the reaction force control motor controls the steering angle of the steering wheel by 0 degrees, an oscillation occurs in the position control error, and this output must be filtered when the autonomous driving mode is canceled.

Accordingly, the position control error amount filter unit 51 filters the increased position control error amount due to the driver's unintentional steering intervention, thereby preventing the steering mode from being unintentionally changed.

A band stop filter may be employed as the position control error amount filter unit 51 .

The position control error amount detection unit 52 detects the position control error amount.

The position control error amount detected by the position control error amount detection unit 52 is relatively large when the driver intervenes in the steering.

The steering mode determining unit 53 determines whether the driver is involved in steering according to whether the holding time for which the amount of position control error is maintained satisfies the driver's steering intervention determination condition, and cancels the autonomous driving mode.

That is, the steering mode determining unit 53 determines that the driver's steering intervention determination condition is satisfied when the position control error amount is included in any one of the preset reference ranges and is maintained for a corresponding set time while being included in the corresponding reference range. When it is determined that the driver's steering intervention determination condition is satisfied, the steering mode determining unit 53 changes the current autonomous driving mode to the driver's steering mode.

Here, the reference range and the set time are the amount of position control error that can be determined that the driver's steering intervention has actually occurred and the holding time thereof, and a plurality of the reference range and the set time can be provided and match each other one-to-one.

In particular, as the reference range increases, the set time decreases. The reason why the setting time decreases as the amount of position control error increases is that the greater the amount of position control error, the stronger the driver's will to intervene in steering. In this case, the relatively fast steering mode must be changed to reflect the driver's will to intervene.

For example, if the reference range is 60 or more and less than 70, the setting time is set to 500 ms, if the reference range is 70 or more and less than 100, the setting time is set to 400 ms, and if the reference range is 100 or more, it may be set to 50 ms.

The reaction force adjusting unit 70 variably controls the reaction force of the steering wheel based on the position control error amount when the steering mode is changed to the steering mode as a result of the determination of the steering intervention determination unit 50 .

That is, when the steering mode is changed to the steering mode as a result of the determination of the steering intervention determination unit 50 , the reaction force adjusting unit 70 variably controls the reaction force of the steering wheel according to the position control error amount at the time when the driver's steering intervention determination condition is satisfied.

In this case, the reaction force adjusting unit 70 gradually reduces the position control output for maintaining the steering angle of the steering wheel at 0 degrees according to the amount of position control error at the time when the driver's steering intervention determination condition is satisfied, and in particular, the driver's steering intervention determination condition The reaction force control output of the steering wheel is gradually increased in proportion to the amount of position control error at the time of satisfaction.

For example, the reaction force control unit 70 maintains the steering angle at 0 degrees of the reaction force control motor of the current reaction force control module 30 based on the amount of position control error at the time when the steering intervention determination condition is satisfied. Blending is processed. The reaction force adjusting unit 70 may be implemented by applying an exponential smoothing filter.

That is, the reaction force adjusting unit 70 variably controls the reaction force according to O ₁ =A _1× K ₁₊ (1-K ₁ )×B ₁ . Here, O ₁ is the final output of the reaction force control motor, B ₁ is the 0 degree position control output of the reaction force control motor, A ₁ is the reaction force control output (reaction force control to give a natural steering feel), and K ₁ is the variable gain. .

Here, during autonomous driving, the variable gain K ₁ value is 0, and when the driver intervenes and the steering intervention is confirmed, the variable gain K ₁ value is gradually changed from 0 to 1.

This variable speed is determined by the amount of position control error of the reaction force control motor when judging steering intervention. The larger the amount of position control error, the faster it changes from 0 to 1, and the slower it changes, the slower it changes. That is, the variable speed of the reaction force of the steering wheel increases in proportion to the amount of position control error when the driver's steering intervention determination condition is satisfied.

Accordingly, the reaction force control unit 70 rapidly decreases the position control output for maintaining the steering angle of the steering wheel at 0 degrees as the amount of position control error at the time when the driver's steering intervention determination condition is satisfied is large, and on the contrary, increases the reaction force control output of the steering wheel This provides a reaction force to the driver.

On the other hand, if the control output of the reaction force control module 30 is 100% reaction force control output, the steering angle of the actuator and the steering angle of the reaction force control module 30 must match. That is, when the steering angle of the wheels of the actuator control module 40 is matched according to the steering angle of the reaction force control module 30 , the autonomous vehicle can be operated in the direction intended by the driver.

Accordingly, the wheel steering angle adjusting unit 80 variably controls the steering angle of the wheel based on the position control error amount according to the determination result of the steering intervention determining unit 50 .

That is, when the steering mode is changed to the steering mode as a result of the determination of the steering intervention determination unit 50, the wheel steering angle adjusting unit 80 variably controls the steering angle of the wheel according to the amount of position control error at the time when the driver's steering intervention determination condition is satisfied.

In this case, the wheel steering angle adjusting unit 80 reduces the control output according to the command steering angle of the autonomous driving system 60 according to the amount of position control error at the time when the driver's steering intervention determination condition is satisfied, while the reaction force control module 30 Increases the actuator control output according to the commanded steering angle of the steering wheel, and increases the steering angle variable speed of the wheel in proportion to the position control error amount when the driver's steering intervention determination condition is satisfied.

For example, the wheel steering angle adjusting unit 80 variably controls the steering angle of the wheel according to O ₂ =A ₂ ×K ₂ +(1-K ₂ )×B ₂ . Here, O ₂ is the actuator final motor control output, A ₂ is the actuator control output according to the command steering angle of the reaction force control module 30, and B ₂ is the actuator control output according to the command steering angle of the autonomous driving system 60.

That is, the wheel steering angle adjusting unit 80 follows the steering angle commanded by the reaction force control module 30 during the period when the K ₂ value changes to 0. When the K ₂ value is 0, the actuator operates the autonomous driving system 60 . The steering angle of the wheel is controlled according to the command steering angle of , but as K ₂ gradually increases to 1, the steering angle of the wheel is controlled according to the command steering angle of the reaction force control module 30 .

Here, the variable gain K _{1 and} K ₂ is the same.

Accordingly, the output may be blended under the condition that the reaction force control output of the reaction force control module 30 and the actuator control output of the actuator control module are identical to each other. While the reaction force control output is changed to 100% for each situation during driver steering intervention, the actuator output of the actuator control module 40 is also the command steering angle position control of the reaction force control module 30 from the command steering angle position control output of the autonomous driving system 60 100% output conversion occurs at the same time as the output.

Hereinafter, a steering control method of an SBW system according to an embodiment of the present invention will be described in detail with reference to FIG. 3 .

3 is a flowchart of a steering control method of an SBW system according to an embodiment of the present invention.

Referring to FIG. 3 , in the autonomous driving mode, the vehicle speed sensing unit 10 detects the vehicle speed of the autonomous driving vehicle, and the steering angle sensing unit 20 detects a steering angle of a steering wheel of the autonomous driving vehicle (S10).

In addition, the steering wheel control module 30 controls the position of the steering wheel control module 30 to a reference angle, that is, 0 degrees through the reaction force control motor. In addition, the actuator control module 40 controls the actuator motor according to the command steering angle of the wheel received from the autonomous driving system 60 to drive the vehicle in the direction set by the autonomous driving system 60 (S20).

In this process, the position control error amount filter unit 51 filters the position control error amount less than the preset minimum threshold value input from the steering wheel control module 30 (S30) to prevent the steering mode from being changed unintentionally. do. Here, the minimum threshold is a typical position control error amount generated in the case of an unintentional steering intervention of a driver, for example, a steering wheel touch.

In addition, the position control error amount detecting unit 52 detects the position control error amount, and the steering mode determining unit 53 determines whether the driver's steering intervention determination condition is satisfied through the position control error amount and the holding time (S40) .

That is, the steering mode determining unit 53 determines that the driver's steering intervention determination condition is satisfied if the position control error amount is included in the preset reference range and is maintained for the preset time in the state included in the reference range, and the current autonomous driving The mode is canceled (S50), and the mode is changed to the driver steering mode.

As the driver's steering mode is changed, the reaction force adjusting unit 70 variably controls the reaction force of the steering wheel according to the amount of position control error at the time when the driver's steering intervention determination condition is satisfied ( S60 ).

In this case, the reaction force adjusting unit 70 reduces the position control output for maintaining the steering angle of the steering wheel at 0 degrees according to the amount of position control error at the time when the driver's steering intervention determination condition is satisfied, and in particular, when the driver's steering intervention determination condition is satisfied Increases the reaction force control output of the steering wheel in proportion to the amount of position control error in

On the other hand, if the control output of the reaction force control module 30 is 100% reaction force control output, the steering angle of the actuator and the steering angle of the reaction force control module 30 must match. Accordingly, the wheel steering angle adjusting unit 80 variably controls the steering angle of the wheel according to the amount of position control error when the driver's steering intervention determination condition is satisfied ( S70 ).

In this case, the wheel steering angle adjusting unit 80 reduces the control output according to the command steering angle of the autonomous driving system 60 according to the amount of position control error at the time when the driver's steering intervention determination condition is satisfied, while the reaction force control module 30 Increases the actuator control output according to the commanded steering angle of the steering wheel, and increases the steering angle variable speed of the wheel in proportion to the position control error amount when the driver's steering intervention determination condition is satisfied.

Accordingly, while the reaction force control output changes to 100% for each situation during driver steering intervention, the actuator output of the actuator is also at the same time as the command steering angle position control output of the reaction force control module 30 from the command steering angle position control output of the autonomous driving system 60 100% output conversion is made in

As described above, the apparatus and method for controlling the steering of the SBW system according to an embodiment of the present invention accurately determine the steering intervention of the driver during autonomous driving and transition the steering mode without feeling heterogeneous.

In addition, the apparatus and method for controlling the steering of an SBW system according to an embodiment of the present invention may provide a transitional steering feel optimized for the driver's steering intervention situation by variably controlling the reaction force of the steering wheel according to the driver's steering intervention situation.

In addition, the apparatus and method for controlling the steering of the SBW system according to an embodiment of the present invention can accurately determine the steering intention of the driver and immediately transition the steering mode when the driver's sudden steering is required due to the occurrence of an emergency during autonomous driving. This can ensure the safety of the driver.

Although the present invention has been described with reference to the embodiments shown in the drawings, this is merely exemplary and those of ordinary skill in the art to which the art pertains are aware that various modifications and equivalent other embodiments are possible therefrom. will understand Accordingly, the true technical protection scope of the present invention should be defined by the following claims.

10: vehicle speed sensing unit 20: steering angle sensing unit
30: reaction force control module 40: actuator control module
50: steering intervention determination unit 51: position control error amount filter unit
52: position control error amount detection unit 53: steering mode determination unit
60: autonomous driving system 70: reaction force control unit
80: wheel steering angle control unit

Claims (28)

a steering intervention determination unit that determines whether an error amount of a position control error of a steering wheel in an autonomous driving mode satisfies a preset driver steering intervention determination condition, and cancels the autonomous driving mode according to the determination result;
a reaction force control unit for variably controlling the reaction force of the steering wheel based on the position control error amount according to the determination result of the steering intervention determination unit; and
and an actuator output adjusting unit for variably controlling a steering angle of a wheel based on the position control error amount according to a determination result of the steering intervention determining unit. The method of claim 1, wherein the steering intervention determination unit
a position control error amount detection unit for detecting the position control error amount; and
Steering control of the SBW system, characterized in that it comprises a steering mode determination unit for terminating the autonomous driving mode by judging whether the driver is involved in the steering according to whether the holding time for which the amount of the position control error is maintained satisfies the driver's steering intervention determination condition Device. The method of claim 2, wherein the steering mode determining unit
The steering control apparatus of the SBW system, characterized in that when the position control error amount is included in a preset reference range and maintained for a preset time in a state included in the reference range, it is determined that the driver's steering intervention is determined. [Claim 4] The steering control apparatus of claim 3, wherein a plurality of each of the reference range and the set time is provided to match each other one-to-one. 5. The apparatus of claim 4, wherein the set time decreases as the reference range increases. The method of claim 2, wherein the steering mode determining unit
Steering control apparatus of the SBW system, characterized in that it further comprises a position control error amount filter for filtering the amount of the position control error less than a preset minimum threshold value. The method of claim 1, wherein the reaction force adjusting unit
The steering control apparatus of the SBW system, characterized in that the reaction force of the steering wheel is variably controlled according to the amount of position control error when the driver's steering intervention determination condition is satisfied. The method of claim 7, wherein the reaction force adjusting unit
The SBW system, characterized in that the position control output for maintaining the steering angle of the steering wheel at 0 degrees is decreased and the reaction force control output of the steering wheel is increased according to the amount of position control error at the time when the driver's steering intervention determination condition is satisfied steering control unit. The method of claim 7, wherein the reaction force control unit
The steering control apparatus of the SBW system, characterized in that the variable speed of the reaction force of the steering wheel is adjusted according to the amount of position control error when the driver's steering intervention determination condition is satisfied. 10. The method of claim 9, wherein the variable speed of the reaction force of the steering wheel is
The steering control apparatus of the SBW system, characterized in that it is proportional to the amount of position control error at the time when the driver's steering intervention determination condition is satisfied. The method of claim 1, wherein the wheel steering angle adjusting unit
The steering control apparatus of the SBW system, characterized in that the steering angle of the wheel is variably controlled according to the amount of position control error when the driver's steering intervention determination condition is satisfied. 12. The method of claim 11, wherein the wheel steering angle adjusting unit
SBW system characterized in that the control output according to the command steering angle of the autonomous driving system is decreased according to the amount of position control error at the time when the driver's steering intervention determination condition is satisfied, and the actuator control output according to the command steering angle of the reaction force control module is increased. of the steering control unit. 12. The method of claim 11, wherein the wheel steering angle adjusting unit
The steering control apparatus of the SBW system, characterized in that the variable speed of the steering angle of the wheel is adjusted according to the amount of position control error when the driver's steering intervention determination condition is satisfied. 14. The method of claim 13, wherein the variable speed of the steering angle of the wheel is
The steering control apparatus of the SBW system, characterized in that it is proportional to the amount of position control error at the time when the driver's steering intervention determination condition is satisfied. determining whether a position control error amount of the steering wheel in the autonomous driving mode satisfies a preset driver steering intervention determination condition, and canceling the autonomous driving mode according to the determination result;
variably controlling a reaction force of a steering wheel based on the amount of position control error according to a result of determining whether the driver's steering intervention determination condition is satisfied; and
and variably controlling a steering angle of a wheel based on the position control error amount according to a result of determining whether the driver's steering intervention determination condition is satisfied. The method of claim 15, wherein the step of canceling the autonomous driving mode comprises:
SBW system, characterized in that the autonomous driving mode is canceled by detecting the amount of the position control error and determining whether the driver is involved in the steering according to whether the holding time for which the amount of the position control error is maintained satisfies the driver's steering intervention determination condition of steering control method. The method of claim 15, wherein the step of canceling the autonomous driving mode comprises:
The steering control method of the SBW system, characterized in that when the position control error amount is included in a preset reference range and maintained for a preset time in a state included in the reference range, it is determined that the driver's steering intervention is determined. 18. The method of claim 17, wherein a plurality of each of the reference range and the set time is provided and matched one-to-one with each other. 19. The method of claim 18, wherein the set time decreases as the reference range increases. The method of claim 16, wherein the step of canceling the autonomous driving mode comprises:
The steering control method of the SBW system, characterized in that it further comprises the step of filtering the position control error amount less than a preset minimum threshold value. The method of claim 16, wherein the step of variably controlling the reaction force of the steering wheel comprises:
The steering control method of the SBW system, characterized in that the reaction force of the steering wheel is variably controlled according to the amount of position control error when the driver's steering intervention determination condition is satisfied. 22. The method of claim 21, wherein the step of variably controlling the reaction force of the steering wheel comprises:
The SBW system, characterized in that the position control output for maintaining the steering angle of the steering wheel at 0 degrees is decreased and the reaction force control output of the steering wheel is increased according to the amount of position control error at the time when the driver's steering intervention determination condition is satisfied Steering control method. 22. The method of claim 21, wherein the step of variably controlling the reaction force of the steering wheel comprises:
The steering control method of the SBW system, characterized in that the variable speed of the reaction force of the steering wheel is adjusted according to the amount of position control error when the driver's steering intervention determination condition is satisfied. 24. The method of claim 23, wherein the variable speed of the reaction force of the steering wheel is
The steering control method of the SBW system, characterized in that it is proportional to the amount of position control error when the driver's steering intervention determination condition is satisfied. 17. The method of claim 16, wherein the variably controlling the steering angle of the wheel comprises:
The steering control method of the SBW system, characterized in that the steering angle of the wheel is variably controlled according to the amount of position control error when the driver's steering intervention determination condition is satisfied. 26. The method of claim 25, wherein the variably controlling the steering angle of the wheel comprises:
SBW system characterized in that the control output according to the command steering angle of the autonomous driving system is decreased according to the amount of position control error at the time when the driver's steering intervention determination condition is satisfied, and the actuator control output according to the command steering angle of the reaction force control module is increased. of steering control method. 26. The method of claim 25, wherein the variably controlling the steering angle of the wheel comprises:
The steering control method of the SBW system, characterized in that the variable speed of the steering angle of the wheel is adjusted according to the amount of position control error when the driver's steering intervention determination condition is satisfied. 28. The method of claim 27, wherein the variable speed of the steering angle of the wheel is
The steering control method of the SBW system, characterized in that it is proportional to the amount of position control error when the driver's steering intervention determination condition is satisfied.

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