KR20150127351A - Steering method and steering device using steering torque offset - Google Patents

Abstract

According to the present invention, a steering method using a steering torque offset value can comprise the following steps of: monitoring whether a vehicle is driven straight for a predetermined time and whether a road is straight; checking an inclination of a straight road in case of determining that the vehicle is driven straight on the straight road for a predetermined time; acquiring steering torque when driving on the straight road in case an inclination of the road is smaller than a predetermined reference value; and calculating an offset value in accordance with pulling of a vehicle body in the acquired steering torque.

Description

TECHNICAL FIELD [0001] The present invention relates to a steering method and a steering apparatus using a steering torque offset value,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steering method and a steering apparatus for a vehicle that can prevent an unintended lane departure from being caused by a driver. More particularly, the present invention relates to a steering method and a steering apparatus for a vehicle that compensates for torque in a state in which a vehicle is tilted due to an axle twist or a road gradient, thereby preventing a vehicle from leaning.

In general, when the vehicle travels in a straight line, a steeping phenomenon may occur in which the vehicle is tilted to one side irrespective of the driver's will due to a lateral wind, a road surface gradient, a road environment, and tire wear.

In the event of such leaning, the driver forcibly manipulated the handle in the opposite direction of the vehicle's tilt to maintain the straightness of the vehicle.

However, when the driver forcibly manipulates the handle, the driver feels fatigued and hinders the driving safety of the vehicle.

This is also true in the case of the recently proposed LKAS (LANE KEEPING ASSIST SYSTEM). As a result, the LKAS performance may be deteriorated due to inclination of the vehicle due to the inclination angle, or the deviation of the vehicle itself due to the alignment failure may cause a deviation in the steering torque. have.

Accordingly, although a technique has been disclosed in which the steering wheel is automatically operated when the vehicle is leaning while it is running, only schemes for applying torque to the steering wheel in the direction opposite to the lean have been proposed, there was.

Korean Patent Publication No. 2013-0040106

The present invention provides a steering method or a steering apparatus capable of detecting an unintentional lane departure using a camera installed in a vehicle and performing a lane departure warning for a driver.

Alternatively, the present invention can be applied to a steering method for assisting lane keeping by performing unintentional lane departure detection using a front camera and performing haptic feedback using MDPS (Motor Driving Power Steering) To provide a steering apparatus.

Alternatively, the present invention intends to provide a steering method or a steering apparatus capable of preventing a lane departure due to a twist of an axle.

Alternatively, the present invention intends to provide a steering method or a steering apparatus capable of preventing lane departure due to inclination of a road.

According to an aspect of the present invention, there is provided a steering method using a steering torque offset value, comprising: monitoring whether a vehicle is running straight ahead for a predetermined time and whether a straight road is running; Confirming the inclination of the straight road when it is determined that the vehicle has traveled straight on the straight road for a predetermined time; Obtaining a steering torque at the time of running on a straight road if the inclination of the road is smaller than a predetermined reference value; And calculating an offset value according to the vehicle body steepness from the obtained steering torque.

Here, in the step of acquiring the steering torque, an average value of the steering torque during the predetermined time can be obtained.

Here, the step of calculating the steering torque offset value may determine a steering torque offset value as a value in a direction opposite to the steering torque at the time of running the straight road.

The method may further include the step of steering the wheel torque value set for the steering wheel operating angle to a wheel torque to which an offset value according to the vehicle body steering is added when the steering wheel operation is detected during driving of the vehicle.

Here, the offset value according to the vehicle body displacement may be limited to a predetermined value between 0.2 Nm and 0.3 Nm in the maximum value of the absolute value.

The method may further include determining whether the predetermined value of the steering torque offset is updated before the step of calculating the steering torque offset value.

Here, in the step of determining whether or not to update, the update can be determined when the absolute value of the steering torque at the time of running the straight road exceeds the predetermined reference value between 0.2 Nm and 0.3 Nm.

According to another aspect of the present invention, there is provided a steering method using a steering torque offset value, comprising: determining a slope of a road under travel; Determining an offset value according to a slope from a slope of the road; Steering to a wheel torque that subtracts an offset value according to the tilt from an absolute value of a wheel torque set for the steering wheel operating angle when the operation of the steering wheel toward the lower direction of the tilt is sensed; And steering the steering wheel to a wheel torque to add an offset value according to the tilt from the absolute value of the wheel torque set for the steering wheel operating angle when the steering wheel operation directed toward the higher direction of the tilt is sensed.

Here, when the steering wheel is in the neutral position, steering may be performed using the offset value according to the tilt as the wheel torque.

In the step of determining the inclination of the road, the inclination of the road can be determined using the measured value of the lateral acceleration sensor of the vehicle, the measured value of the yaw rate sensor, and the measured value of the vehicle speed sensor.

Here, the maximum value of the absolute value of the offset value according to the road inclination may be limited to a predetermined value between 0.4 Nm and 0.6 Nm.

Here, in the step of determining the offset value according to the slope, an offset value according to the slope may be determined as a linearly proportional value according to the slope angle of the road determined.

Here, the larger the speed of the vehicle, the smaller the slope of the linear function.

According to another aspect of the present invention, there is provided a steering method using a steering torque offset value, comprising: determining a slope of a road under travel; Calculating an offset value according to a road gradient if a gradient exceeding a predetermined reference value exists; Determining whether the vehicle is traveling straight ahead if there is no inclination exceeding the predetermined reference value; Detecting wheel torque during straight steering when the vehicle is running straight; And calculating an offset value according to the vehicle deviations with the detected wheel torque.

Here, when the steering wheel operation is detected during the running of the vehicle, a wheel torque value obtained by adding an offset value according to the estimated road gradient to the wheel torque value set for the steering wheel operation angle, and an offset value according to the calculated vehicle- And a steering step.

According to another aspect of the present invention, there is provided a steering apparatus using a steering torque offset value, comprising: a traveling environment determining unit determining a traveling environment including a slope of a road on which a vehicle is traveling; A steering torque offset determining unit for setting an offset value according to the determined driving environment; And a steering control unit performing steering with a wheel torque value set for the steering wheel operating angle and performing steering by adding the steering torque offset value to the set wheel torque value.

Here, the traveling environment determination unit may monitor whether the vehicle is traveling straight ahead and whether the vehicle is traveling straight for a predetermined time.

Here, the steering torque offset determining unit may determine that the vehicle has traveled straight on the straight road for a predetermined period of time, if the inclination of the straight road is smaller than the predetermined reference value, obtain the steering torque during straight traveling, It is possible to calculate the offset value according to the vehicle body displacement.

Here, the steering torque offset determination unit may determine an offset value according to a tilt from the tilt of the road.

Here, the steering torque offset determining unit may determine an offset value according to a slope and an offset value according to a vehicle body displacement from the slope of the road, and the steering control unit may calculate an offset value according to the slope, And the offset value is added to the steering angle.

The steering method or the steering apparatus according to the present invention according to the above-described configuration has an advantage that an unintended lane departure can be prevented.

Alternatively, the steering method or the steering apparatus of the present invention has an advantage that it can warn a lane departure (LKA: Lane Keeping Assist) by performing an audiovisual warning to a driver.

Alternatively, the steering method or the steering apparatus of the present invention may assist lane keeping by performing unintentional lane departure detection using a forward camera and performing haptic feedback using MDPS There is an advantage.

Alternatively, the steering method or the steering apparatus of the present invention has an advantage that the lane departure due to the twist of the axle can be prevented.

Alternatively, the steering method or the steering apparatus of the present invention has an advantage that it is possible to prevent lane departure due to inclination of the road.

1 is a conceptual diagram illustrating a feedback control process for determining a preferred steering torque that may be used in an implementation of the present invention;
2 is a conceptual diagram showing an outline of a steering method according to an embodiment of the present invention;
3 is a conceptual diagram showing that an unintentional steering torque is generated according to the inclination of the road;
FIG. 4 is a flowchart illustrating a process of determining an offset value according to an inclination of a road according to an embodiment of the present invention and steering the road according to the offset value. FIG.
FIG. 5 is a graph that serves as a reference for determining an offset value according to a tilt in step S230 of FIG.
FIG. 6 is a conceptual diagram showing a state in which a steering torque offset value determined according to the graph of FIG. 5 is applied.
FIG. 7 is a flowchart illustrating a process of determining an offset value according to a vehicle steepness according to another embodiment of the present invention and steering the steering angle according to the offset value. FIG.
FIG. 8 is a graph that serves as a reference for determining an offset value according to a tilt in step S230 of FIG.
FIG. 9 is a conceptual diagram showing that an unintentional steering torque is generated due to vehicle deviations. FIG.
FIG. 10 is a flow chart illustrating a steering control method according to an integrated form embodiment reflecting the flow diagram of FIG. 4 and FIG. 7 in the flow diagram structure of FIG. 2;
11 is a block diagram illustrating a steering apparatus using a steering torque offset value according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

1 is a conceptual diagram showing a feedback control process for determining a desired steering torque that can be used in the implementation of the present invention.

In the illustrated conceptual diagram, S60 means to determine a preferable steering angle at a specific point in time, and S70 means to determine a preferable steering angle at the next point in time.

The preferred steering angle determined at step S60 is reflected to the steering angle control at step S62. In step S63, a difference between the desired steering angle determined in step S60 and the actual vehicle steering angle is calculated, and a value to be feedback-reflected is determined in step S64. In step S69, the feedback reflected value is added to the preferable steering angle, and the desired steering angle is determined in step S70.

2 is a conceptual diagram showing an outline of a steering method according to an embodiment of the present invention.

The steering method according to an embodiment of the present invention includes: (S10) a step of determining a tilt of a road under driving; (S20) of calculating an offset value according to a road gradient if a gradient exceeding a predetermined reference value exists; Determining whether the vehicle is traveling straight ahead if the inclination exceeding the predetermined reference value does not exist (S30); A step (S40) of detecting a wheel torque at the time of straight steering when the vehicle is running straight; And a step (S50) of calculating an offset value according to the vehicle steepness with the detected wheel torque.

In step S20 or step S50, steering can be performed by applying an offset value according to the estimated road inclination or vehicle deviating.

FIG. 3 is a conceptual diagram showing that an unintentional steering torque is generated according to the inclination of a road. FIG. 4 is a flowchart illustrating a process of determining an offset value according to an inclination of a road according to an embodiment of the present invention, It is a flow chart. The flowchart of FIG. 4 may be one in which step S20 of FIG. 2 is embodied.

As shown in Fig. 3, when the vehicle travels on a road having a right-left inclination of phi, the steering torque shown by Fbank is applied to the steering apparatus of the vehicle such as the steering handle even when the steering wheel is set to neutral. In FIG. 4, an offset value according to the inclination of the road, which can offset the steering torque indicated by the Fbank, is determined, and the steering is performed using the determined steering torque offset value.

The illustrated steering method includes: determining a tilt of a road under operation (S210); Determining an offset value according to the slope from the slope of the road (S230); (S240). When the operation of the steering wheel toward the lower direction of the tilt is sensed, the absolute value of the wheel torque set for the steering wheel operating angle (S250) (S260) steering wheel torque to subtract the value; And steering (S280) steering wheel steering from the absolute value of the wheel torque set for the steering wheel operating angle (S270) to the wheel torque for adding the offset value according to the tilt . As a result of step S240, if the steering wheel is in the neutral position, steering may be performed using the offset value according to the tilt as the wheel torque (S290).

In the step S210 of determining the inclination of the road, the inclination of the road can be determined using the data obtained from various sensing means. The step S210 may be the step S10 of FIG.

For example, a traveling image photographed by a camera installed in front of the vehicle is analyzed to determine the horizontal plane of the road under travel, and the gravity direction determined from the gyro sensor (or acceleration sensor) of the vehicle is applied to the horizontal plane of the road, The slope can be judged.

Alternatively, the inclination of the road can be determined using the measured value of the lateral acceleration sensor of the vehicle, the measured value of the yaw rate sensor, and the measured value of the vehicle speed sensor. In this case, it is possible to further determine the traveling speed of the vehicle from the vehicle speed sensor in step S210. The concrete formula for determining the acceleration depending on the inclination of the road and the inclination of the road from the measured values is shown in Equation 1 below.

a _{y _ sensor} : Measured value of lateral acceleration sensor

Ψ ' _sensor : Yaw rate sensor measurement value

V _x : vehicle speed

g: gravitational acceleration

φ: road inclination angle

a _bank : gravitational acceleration component for road gradients

In the equation (1), the gravitational acceleration component value according to the road gradient is obtained from the measured value of the lateral acceleration sensor, the measured value of the yaw rate sensor, and the measured value of the vehicle speed sensor, It is possible to obtain the inclination angle?.

A method of determining the offset value according to the tilt in step S230 will be described later.

Depending on the implementation, the offset value may have a different value depending on the running speed of the vehicle. This reflects the fact that as the vehicle speed increases, the ratio of the force due to the inertia of the vehicle moving rather than the force due to the gradient of the road becomes larger.

In this case, an offset value according to the tilt is determined using the road gradient determined in step S210 and the traveling speed determined in step S205. First, a first-order steering torque offset value according to the road gradient is calculated, The final steering torque offset value can be calculated by multiplying the steering torque offset value by a weight that becomes lower as the traveling speed is higher.

FIG. 5 is a graph illustrating a reference for determining an offset value according to a tilt in step S230, and FIG. 6 is a conceptual diagram illustrating a state in which a steering torque offset value determined according to the graph of FIG. 5 is applied.

When the graph is applied, the steering torque offset value? (?), Which is linearly proportional to the inclination angle? Determined in step S210, is determined. At this time, the steering torque offset value? (?) Has a maximum value that remains constant even if the inclination angle? Is large.

The application of the maximum value to the steering torque offset value (? (?)) Shows that when the steering torque offset value? (?) Which is too large is applied, the driver feels a sense of heterogeneity in steering feeling, . In addition, since a significant left and right steep slope of a traveling road can predict that there is a large leaning of a driver, the maximum value does not greatly affect safety driving. 5, the maximum value of the steering torque offset value determined in a linear fashion is determined in the range of (+/-) 0.4 Nm to (+/-) 0.6 Nm, in consideration of the necessity of the safe driving and the steering feeling of the driver. . For example, the maximum value of the steering torque offset value may be determined as (+/-) 0.5 Nm.

When the steering torque offset value determined according to the graph shown in FIG. 6 is applied, as shown in FIG. 6, the steering torque is increased in the departure prevention control from the lower side to the lower side and the steering torque is decreased in the departure- The steering control can be performed in a manner that is described below.

Depending on the implementation, the greater the speed of the vehicle, the smaller the slope of the linear function. This reflects the fact that the higher the speed of the vehicle, the greater the ratio of the force due to the inertia of the vehicle moving than the force due to the gradient of the road.

FIG. 7 is a flowchart illustrating a process of determining an offset value according to a vehicle drift according to another embodiment of the present invention and steering the steering angle according to the offset value.

The illustrated steering method includes steps S410 to S420 for monitoring whether the vehicle is traveling straight ahead and whether the vehicle is traveling on a straight road for a predetermined time period; If it is determined that the vehicle has traveled straight on the straight road for a predetermined time, confirming the inclination of the straight road (S430); If the inclination of the road is smaller than the predetermined reference value (S435), a step S440 of acquiring the steering torque at the time of running on the straight road; And a step S460 of calculating an offset value according to the vehicle body steepness in the steering torque.

Although steps S410 to S420 for confirming whether a straight road is running have been performed prior to steps S430 and S435 for confirming the inclination of the road, steps for confirming the inclination of the road S430, and S435 may be performed prior to steps S410 to S420 for confirming whether the vehicle is traveling on a straight road. The latter case corresponds to the order of steps S10 and S30 of FIG. 2, and in this case, steps S430 and S435 may be performed in step S10 of FIG.

Steps S410 to S420 for confirming whether the straight road is running include steps S410 to S410 of confirming that the road on which the vehicle is traveling is a straight road; (S415) confirming that the vehicle is running straight on the road; And confirming that the rectilinear time of the straight road is maintained longer than a predetermined reference time (S420).

Depending on the implementation, steps S410 and S415 may be performed in a reversed order.

The steps S410 and S415 may be performed using data obtained from various sensing means installed in the vehicle.

For example, it is possible to determine whether the vehicle is in a straight line from the measured value of the yaw rate sensor of the vehicle in step S410.

For example, it is possible to determine whether the vehicle is going straight ahead in step S415 from the measured value of the lateral acceleration sensor of the vehicle and the measured value of the yaw rate sensor of the vehicle.

For example, it is possible to determine whether the steering wheel steering angle of the vehicle goes straight to the step S415.

The road inclination determination method of step S430 may be similar to that of FIG. 4, and thus a duplicate description will be omitted.

In step S440, various methods may be applied to detect the steering wheel torque. For example, it is possible to simply determine the steering wheel torque as the average value of the steering wheel torque by the driver's manipulation of the steering wheel. Alternatively, the straight steering wheel torque can be calculated from the measured value of the lateral acceleration sensor of the vehicle in the straight section and the measured value of the yaw rate sensor of the vehicle.

Various conditions may be applied as update conditions to the illustrated S450 step. For example, the wheel torque required for the straight steering detected in step S440 may be updated when the wheel torque exceeds a predetermined reference value (e.g., 0.2 Nm to 0.3 Nm, more specifically, 0.25 Nm). Alternatively, if the wheel torque required for the straight steering detected in step S440 is detected to be accumulated more than a predetermined reference number, it may be updated.

Steps S410 to S470 illustrate a process of calculating an offset value according to vehicle drift and setting it in an internal storage unit, and steps S480 and S490 illustrate a process of reflecting the set offset value to the steering operation .

That is, when sensing the manipulation of the steering wheel during running of the vehicle, the wheel torque corresponding to the steering wheel operating angle is calculated (S480), and the offset according to the vehicle body deviation calculated in steps S410 to S470 (S490). ≪ / RTI >

According to the implementation, in step S490, not only the offset value according to the vehicle deviations calculated in the flowchart of FIG. 7 but also the offset value according to the slope calculated by the flowchart of FIG. 4 can be applied together.

FIG. 8 is a graph showing a reference for determining an offset value according to vehicle drift in step S460, and FIG. 9 is a conceptual diagram showing a state in which a steering torque offset value determined according to the graph of FIG. 8 is applied. In FIG. 8, Ti is shown to indicate that the measured torque is measured, and a general torque (T) will be described in the following description.

When the illustrated graph is applied, the steering torque offset value? (T), which is linearly proportional to the steering wheel torque T determined in step S440, is determined. At this time, the steering torque offset value? (T) has a maximum value that remains constant even when the steering wheel torque T increases linearly.

The application of the maximum value to the steering torque offset value (T (T)) is performed by adjusting the steering torque offset value only by adjusting the steering torque offset value (? (T) This is because the risk of vehicle accidents increases.

Taking into consideration the necessity of the safe operation and maintenance, the maximum value of the steering torque offset value determined as a function of the first function as shown in FIG. 8 is determined in the range of (+/-) 0.2 Nm to (+/-) 0.3 Nm It is appropriate. For example, the maximum value of the steering torque offset value may be determined to be (+/-) 0.25 Nm.

Also, the steering torque offset value? (T) can be maintained at 0 until the straight steering wheel torque T determined in step S440 reaches the minimum reference value. This is because the straight steering wheel torque T that is less than the minimum reference value may be generated temporarily for other reasons such as a slight inclination of the road, not a leaning of the vehicle.

When the steering torque offset value determined according to the graph shown in FIG. 9 is applied, the steering control can be performed so that the vehicle travels in a linear direction even when the vehicle is leaning, as shown in FIG.

FIG. 10 shows a steering control method according to an integrated form embodiment reflecting the flow diagram of FIG. 4 and FIG. 7 in the flow diagram structure of FIG.

The steering method according to the illustrated embodiment includes: (S10) judging a tilt of a road being driven first; If the slope of the road is compared with a predetermined reference value (S15), and if there is a slope exceeding a predetermined reference value, calculating an offset value according to the slope of the road (S230); (S240). When the operation of the steering wheel toward the lower direction of the tilt is sensed, the absolute value of the wheel torque set for the steering wheel operating angle (S250) (S260) steering wheel torque to subtract the value; (S280) steering the steering wheel to a wheel torque to add an offset value according to the tilt from an absolute value of a wheel torque set for the steering wheel operating angle (S270) when the steering wheel operation toward the high direction of the tilt is sensed; If it is determined that the steering wheel is in the neutral position as a result of step S240, steering the steering wheel as an offset value according to the inclination (S290); If it is determined that there is no inclination exceeding the predetermined reference value as a result of the comparison in step S15, monitoring (S410 to S420) whether the vehicle is running in a straight line for a predetermined time and whether a straight road is running; If it is determined that the vehicle has traveled straight on the straight road for a predetermined time, obtaining (S440) a steering torque at the time of traveling on a straight road; A step S450 of confirming an update condition of an offset value according to a vehicle body displacement; And a step S467 of calculating and setting an offset value according to the vehicle body steepness in the steering torque.

Each step of the flowchart of FIG. 10 can be performed in a manner similar to the corresponding steps on the flowchart of FIG. 4 or 7, and redundant description will be omitted.

11 illustrates a steering apparatus using a steering torque offset value according to an embodiment of the present invention.

The steering control apparatus (100) using the steering torque offset value shown includes a traveling environment determination unit (120) for determining a traveling environment including a slope of a road on which the vehicle is traveling; A steering torque offset determination unit (140) for setting a steering torque offset value according to the determined driving environment; A steering control unit (160) for steering by performing steering with a wheel torque value set for an operating angle of the steering wheel, and adding the steering torque offset value to the set wheel torque value; And a storage unit 180 for storing the steering torque offset value according to the set driving environment.

The traveling environment determination unit 120 can monitor whether the vehicle is traveling straight ahead and whether the vehicle is traveling straight for a predetermined time, and can monitor the inclination of the road. That is, at least one of steps S10 and S30 of FIG. 2, step S210 of FIG. 4, and steps S410 to S435 of FIG. 7 may be performed.

When the inclination of the straight road is smaller than the predetermined reference value, the steering torque offset determining unit 140 obtains the steering torque at the time of running on the straight road, and when the inclination of the straight road is smaller than the predetermined reference value, It is possible to calculate the offset value according to the vehicle body leaning from the torque.

Alternatively, the steering torque offset determining unit 140 may determine an offset value according to a slope from the slope of the road.

Alternatively, the steering torque offset determining unit 140 may determine an offset value according to a tilt and an offset value according to a vehicle body tilt from a tilt of the road, and the steering control unit may calculate an offset according to the tilt, And an offset value according to the vehicle body steepness are added.

The steering torque offset determining unit 140 may perform at least one of steps S20 and S50 in FIG. 2, step S230 in FIG. 4, and steps S460 and S470 in FIG.

The steering control unit 160 may perform steering by adding an offset value according to the inclination and an offset value according to the vehicle body displacement to the set wheel torque value. The storage unit 180 may store not only the set values of the offset values according to the road inclination and the offset values according to the vehicle body drift but also the data necessary to obtain the offset values ) Or data necessary to obtain the wheel torque according to the wheel operation angle (e.g., a mapping table for the wheel operation angle and the wheel torque).

The steering control unit 160 may perform at least one of steps S240 to S290 of FIG. 4, steps S480 and S490 of FIG.

It should be noted that the above-described embodiments are intended to be illustrative, not limiting. In addition, it will be understood by those of ordinary skill in the art that various embodiments are possible within the scope of the technical idea of the present invention.

120:
140: Steering torque offset determination unit
160:
180:

Claims (20)

Monitoring whether the vehicle is running straight ahead and whether the road is running straight for a predetermined time;
Confirming the inclination of the straight road when it is determined that the vehicle has traveled straight on the straight road for a predetermined time;
Obtaining a steering torque at the time of running on a straight road if the inclination of the road is smaller than a predetermined reference value; And
Calculating an offset value according to the vehicle body steepness from the obtained steering torque
And a steering torque offset value including the steering torque offset value.
The method according to claim 1,
In the step of acquiring the steering torque,
And a steering torque offset value for obtaining an average value of the steering torque during the predetermined time.
The method according to claim 1,
The step of calculating the steering torque offset value includes:
And a steering torque offset value that determines a value in a direction opposite to the steering torque at the time of running the straight road as the steering torque offset value.
The method according to claim 1,
Steering the wheel to a wheel torque added with an offset value according to the vehicle body displacement to a wheel torque value set for the steering wheel operating angle when the steering wheel operation is sensed while the vehicle is running
And a steering torque offset value that further includes a steering torque offset value.
The method according to claim 1,
Wherein the steering torque offset value is limited to a predetermined value between 0.2 Nm and 0.3 Nm.
The method according to claim 1,
Before the step of calculating the steering torque offset value,
Determining whether to update the predetermined steering torque offset value
And a steering torque offset value that further includes a steering torque offset value.
The method according to claim 6,
Wherein the step of determining whether or not the update is made using the steering torque offset value for determining an update when the absolute value of the steering torque at the time of traveling the straight road exceeds a predetermined reference value between 0.2 Nm and 0.3 Nm.
Determining a slope of a road under travel;
Determining an offset value according to a slope from a slope of the road;
Steering to a wheel torque that subtracts an offset value according to the tilt from an absolute value of a wheel torque set for the steering wheel operating angle when the operation of the steering wheel toward the lower direction of the tilt is sensed; And
Steering to a wheel torque to add an offset value according to the tilt from an absolute value of the wheel torque set for the steering wheel operating angle when the steering wheel operation toward the high direction of the tilt is sensed
And a steering torque offset value including the steering torque offset value.
9. The method of claim 8,
When the steering wheel is in a neutral position, steering an offset value according to the tilt as a wheel torque
And a steering torque offset value that further includes a steering torque offset value.
9. The method of claim 8,
In the step of determining the inclination of the road,
A steering method using a steering torque offset value for determining a slope of a road using a measured value of a lateral acceleration sensor of a vehicle, a measured value of a yaw rate sensor, and a measured value of a vehicle speed sensor.
9. The method of claim 8,
Wherein the steering torque offset value is limited to a predetermined value between 0.4 Nm and 0.6 Nm.
9. The method of claim 8,
In the step of determining the offset value according to the slope,
And a steering torque offset value in which an offset value according to the slope is determined as a linearly functionally proportional value according to the determined slope angle of the road.
13. The method of claim 12,
And the slope of the first order function decreases as the vehicle speed increases.
Determining a slope of a road under travel;
Calculating an offset value according to a road gradient if a gradient exceeding a predetermined reference value exists;
Determining whether the vehicle is traveling straight ahead if there is no inclination exceeding the predetermined reference value;
Detecting wheel torque during straight steering when the vehicle is running straight; And
Calculating an offset value according to the vehicle deviation with the detected wheel torque
And a steering torque offset value including the steering torque offset value.
15. The method of claim 14,
Steering wheel steering apparatus according to any one of claims 1 to 3, wherein when the steering wheel operation is detected during driving of the vehicle, steering is performed to a wheel torque value set for the steering wheel operating angle with an offset value according to the estimated road gradient and an offset value according to the calculated vehicle- step
And a steering torque offset value that further includes a steering torque offset value.
A traveling environment determining unit for determining a traveling environment including a slope of a road on which the vehicle is traveling;
A steering torque offset determining unit for setting an offset value according to the determined driving environment; And
Steering is performed with the wheel torque value set for the steering wheel operating angle,
And a steering torque control unit that performs steering by adding the steering torque offset value to the set wheel torque value,
Wherein the steering torque offset value includes the steering torque offset value.
17. The method of claim 16,
Wherein the traveling environment determination unit uses a steering torque offset value for monitoring whether the vehicle is traveling straight ahead for a predetermined time and whether the traveling road is straight or not.
18. The method of claim 17,
Wherein the steering torque offset determining section determines,
When the inclination of the straight road is smaller than the predetermined reference value, the steering torque at the time of running on the straight road is obtained, and the offset value according to the steering effort is calculated from the steering torque Wherein the steering torque offset value is calculated based on the steering torque offset value.
17. The method of claim 16,
Wherein the steering torque offset determining section determines,
Wherein an offset value according to an inclination is determined from an inclination of the road.
17. The method of claim 16,
Wherein the steering torque offset determining section determines,
Determining an offset value according to a tilt from the tilt of the road and an offset value according to the tilt of the vehicle,
Wherein the steering control unit performs steering by adding an offset value according to the inclination and an offset value according to vehicle body steep to the set wheel torque value.

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