Steering control apparatus and method

Abstract

The present disclosure relates to a steering control device and method. Specifically, the steering control device according to the present disclosure includes a road surface groove detection unit that detects a groove in the road surface located in the lane of travel of a vehicle, a torque detection unit that detects column torque in a steering column, and a control unit that calculates a first steering damping upward rate based on the detected groove in the road surface, calculates a second steering damping upward rate based on the column torque detected in the steering column, calculates a final steering damping upward rate based on the first steering damping upward rate and the second steering damping upward rate, and generates a control signal for applying the calculated final steering damping upward rate.

Description

Technology Field

[0001] The present embodiments relate to a steering control device and method. Background Technology

[0002] Recently, as vehicle technology advances, various control systems capable of ensuring vehicle stability and driver convenience are being developed.

[0003] Among these various control systems, the Lane Keeping Assist System (hereinafter referred to as 'LKA') is a system that recognizes lanes using a camera while driving on the road and controls the Motor Driven Power Steering (hereinafter referred to as 'MDPS') by applying a small steering force according to the shape of the road and the driving condition of the vehicle.

[0004] If a disturbance occurs due to grooves in the road surface while the vehicle is maintaining the lane keeping assist system, the vehicle's behavior changes, which may cause anxiety for the driver. The problem to be solved

[0005] Against this background, the present disclosure aims to provide a steering control device and method for adjusting steering damping according to grooves in the road surface. means of solving the problem

[0006] In order to solve the aforementioned problem, in one aspect, the present disclosure provides a steering control device comprising: a road surface groove detection unit that detects a groove in the road surface located in the lane of travel of a vehicle; a torque detection unit that detects column torque in a steering column; and a control unit that calculates a first steering damping upward rate based on the detected groove in the road surface, calculates a second steering damping upward rate based on the column torque detected in the steering column, calculates a final steering damping upward rate based on the first steering damping upward rate and the second steering damping upward rate, and generates a control signal for applying the calculated final steering damping upward rate.

[0007] In another aspect, the present disclosure provides a steering control method comprising: a sensor information receiving step of detecting a groove in the road surface located in the lane of travel of a vehicle and detecting column torque in a steering column; a first steering damping upward rate calculation step of calculating a first steering damping upward rate based on the detected groove in the road surface; a second steering damping upward rate calculation step of calculating a second steering damping upward rate based on column torque detected in the steering column; and a control signal generation step of calculating a final steering damping upward rate based on the first steering damping upward rate and the second steering damping upward rate, and generating a control signal for applying the calculated final steering damping upward rate. Effects of the invention

[0008] According to the present disclosure, a steering control device and method can be provided to mitigate a target steering angle by desensitizing steering changes under specific road surface conditions. Brief explanation of the drawing

[0009] Figure 1 is a diagram illustrating the torque required by a lane-following system and the steering angle of the vehicle when the vehicle passes over a road surface having a specific pattern. FIG. 2 is a block diagram illustrating a steering control device according to one embodiment of the present disclosure. FIG. 3 is a drawing for explaining how to calculate a first steering damping upward rate based on the spacing between the grooves of the road surface and the tire grooves of the vehicle according to one embodiment. FIGS. 4 and 5 are drawings for explaining how to calculate a first steering damping upward rate according to the groove direction of the road surface and the groove direction of the tire according to one embodiment. FIG. 6 is a flowchart illustrating a steering control method according to one embodiment of the present disclosure. FIG. 7 is a flowchart illustrating the calculation of a first steering damping upward rate according to one embodiment. FIG. 8 is a flowchart illustrating the calculation of a second steering damping upward rate according to one embodiment. Specific details for implementing the invention

[0010] Some embodiments of the present disclosure are described in detail with reference to the exemplary drawings. In assigning reference numerals to the components of each drawing, the same components may have the same reference numeral as much as possible, even if they are shown in different drawings. Furthermore, in describing the embodiments, if it is determined that a detailed description of related known components or functions may obscure the essence of the technical concept, such detailed description may be omitted. Where terms such as "comprising," "having," or "consisting of" are used in this specification, other parts may be added unless "only" is used. Where a component is expressed in the singular, it may include a plural unless otherwise specified.

[0011] Additionally, terms such as first, second, A, B, (a), (b), etc., may be used to describe the components of the present disclosure. These terms are used merely to distinguish the components from other components, and the nature, order, sequence, or number of the components are not limited by such terms.

[0012] In describing the positional relationship of components, where it is stated that two or more components are "connected," "combined," or "joined," it should be understood that while the two or more components may be directly "connected," "combined," or "joined," they may also be "connected," "combined," or "joined" with other components "intervened." Here, the other components may be included in one or more of the two or more components that are "connected," "combined," or "joined" with one another.

[0013] In describing the temporal flow relationship regarding components, methods of operation, or methods of production, for example, when the temporal or sequential relationship is described using "after," "following," "next," or "before," it may include cases where the relationship is not continuous unless "immediately" or "directly" is used.

[0014] Meanwhile, where numerical values ​​or corresponding information regarding a component (e.g., levels, etc.) are mentioned, even without separate explicit notation, the numerical values ​​or corresponding information may be interpreted as including a range of error that may occur due to various factors (e.g., process factors, internal or external shocks, noise, etc.).

[0015] Figure 1 is a diagram illustrating the torque required by a lane-following system and the steering angle of the vehicle when the vehicle passes over a road surface having a specific pattern.

[0016] Referring to Fig. 1, when a normal vehicle is driving and passes over a road surface in the lane it is driving in, the steering may become unstable due to the road surface. In addition, when the vehicle is driving using a lane centering following system such as LKAS (Lane Keeping Assist System) or LFA (Lane Following Assist), sensor data also changes as it drives over the road surface, so the target steering angle presented by the system changes frequently, which may cause anxiety to the driver.

[0017] Accordingly, a method was needed to mitigate the target steering angle that changes under specific road surface conditions.

[0018] Hereinafter, a steering control device (10) according to one embodiment of the present disclosure, which implements mitigation of the phenomenon by desensitizing steering change when a specific pattern of road surface is continuously repeated, will be described with reference to the attached drawings.

[0019] FIG. 2 is a block diagram for explaining a steering control device (10) according to one embodiment of the present disclosure.

[0020] Referring to FIG. 2, a steering control device (10) according to one embodiment of the present disclosure may include a road surface groove detection unit (110), a torque detection unit (120) (110), and a control unit (130), etc.

[0021] The steering control device (10) can transmit and receive data with the driver assistance system (ADAS) equipped in the vehicle. The control unit (130) can provide information about an object to the driver assistance system (Advanced Driver Assistance Systems; ADAS) included in the vehicle equipped with a radar device.

[0023] The steering control device (10) can detect the pattern of the road surface and detect the column torque to calculate the first steering damping upward rate and the second steering damping upward rate, and calculate the final steering damping upward rate based on each upward rate to adjust the target steering angle.

[0024] In one embodiment, the steering control device (10) may be applied only when the vehicle is driven by an LKAS, LFA, or lane centering system.

[0025] According to the above description, the steering control device (10) can reduce the range of change of the target steering angle that changes while driving on a specific road surface by adjusting the steering damping.

[0026] The road surface groove detection unit (110) can detect the pattern of the road surface located in the lane of travel of the vehicle.

[0027] Specifically, the road surface groove detection unit (110) can determine whether grooves are formed on the road surface located in the driving lane through an image sensor, etc. Additionally, the road surface groove detection unit (110) can determine whether grooves on the road surface are formed by repeating a specific pattern.

[0028] Accordingly, in one embodiment, the road surface groove detection unit may include an image sensor for detecting grooves on the road surface in front or on the side. The image sensor may detect grooves on the road surface existing within a detection distance according to the specifications of each sensor and output them as image data or video data.

[0029] In the case where the aforementioned image data or video data includes grooves on the road surface, that is, when the road surface groove detection unit (110) detects grooves on the road surface and generates image data or video data, the generated image data or video data may represent road surface information.

[0030] In the present disclosure, image information captured from an image sensor may refer to image data captured from an image sensor.

[0031] Image data captured by the image sensor can be generated in one of the following formats: Raw AVI, MPEG-4, H.264, DivX, or JPEG. For example, image data captured by the front image sensor or the side image sensor can be processed by a processor. Here, the processor may be included in each image sensor and may be included in the control unit (130) described below. Additionally, a separate module that performs the function of the processor may be installed.

[0032] Accordingly, the road surface groove detection unit (110) can receive road surface information, which is image data or video data containing grooves of the road surface detected by the received image sensor.

[0033] Road surface information may include the location of grooves formed on the road surface, the direction of the grooves, and the pattern of the grooves.

[0034] Here, object information can be calculated based on still images that are divided according to the frame rate of the aforementioned image data.

[0035] Additionally, in one embodiment, the road surface groove detection unit (110) may further include a radar sensor for detecting grooves in the road surface. Here, the radar sensor may include an antenna unit, a receiver unit, and a transmitter unit. The antenna unit includes one or more transmitter antennas and one or more receiver antennas, and each transmitter and receiver antenna may be an array antenna in which one or more radiating elements are connected in series by a feed line, but is not limited thereto.

[0036] This antenna section includes a plurality of transmitting antennas and a plurality of receiving antennas, and may have various types of antenna array structures depending on the arrangement order and spacing thereof.

[0037] The transmitting unit can switch to one of the multiple transmitting antennas included in the antenna unit and transmit a transmission signal through the switched transmitting antenna or transmit a transmission signal through a multi-transmission channel assigned to the multiple transmitting antennas.

[0038] This transmitter includes an oscillator that generates a transmission signal for a single transmission channel assigned to a switched transmitting antenna or for multiple transmission channels assigned to multiple transmitting antennas. This oscillator may include, for example, a voltage-controlled oscillator (VCO) and an oscillator.

[0039] The receiver can receive the received signal reflected from the grooves in the road surface through the receiving antenna.

[0040] In addition, the receiver can switch to one of a plurality of receiving antennas to receive a receiving signal, which is a reflected signal of a transmission signal transmitted through the switched receiving antenna that is reflected by a target, or receive a receiving signal through a multi-receiving channel assigned to a plurality of receiving antennas.

[0042] Accordingly, the road surface groove detection unit (110) may include a radar signal transmission module that controls the transmission of a radar signal toward a groove on the road surface using a transmission antenna, and a reception module that receives a reception signal reflected from the groove on the road surface through a reception antenna.

[0043] The road surface groove detection unit (110) can perform a signal reception operation of receiving a signal that detects grooves on the road surface through a transmitting antenna and a receiving antenna, and a signal processing operation of processing the received signal to calculate road surface information. Here, the received signal is received through the aforementioned receiving module, and based on the received signal, road surface information can be calculated through FFT (Fast Fourier Transform) and measurements.

[0044] The torque detection unit (120) can detect column torque from the steering column. Specifically, the torque detection unit (120) can detect column torque from the steering column to determine grip information regarding the driver's steering wheel. Accordingly, the control unit (130) described later can calculate the steering damping upward rate based on the value of the column torque detected by the torque detection unit (120).

[0045] Additionally, the torque detection unit (120) may further include a capacitive sensor to determine whether the driver is gripping the steering wheel.

[0046] The control unit (130) can calculate a first steering damping upward rate based on the detected road surface pattern, calculate a second steering damping upward rate based on the column torque detected in the steering column, calculate a final steering damping upward rate based on the first steering damping upward rate and the second steering damping upward rate, and generate a control signal to apply the calculated final steering damping upward rate.

[0047] FIG. 3 is a drawing for explaining how to calculate a first steering damping upward rate based on the spacing between the grooves of the road surface and the tire grooves of the vehicle according to one embodiment.

[0048] The control unit (130) can receive a pattern of the road surface from the road surface information, which is the detection result of the sensor unit (110).

[0049] Referring to FIG. 3, the control unit (130) can calculate a first steering damping upward rate greater than or equal to a first reference value when the groove spacing formed on the road surface is detected to be within a predetermined range with respect to the groove spacing of the tire mounted on the vehicle. For example, FIG. 3a may represent the spacing of the grooves formed on the road surface. And FIG. 3b may represent the spacing of the grooves formed on the tire. When the difference in spacing between FIG. 3a and FIG. 3b is less than or equal to a predetermined spacing, the control unit (130) determines that it is a steering damping upward condition and can calculate a first steering damping upward rate greater than or equal to a first reference value.

[0050] As the spacing of the grooves formed on the road surface and the spacing of the grooves formed on the tire are similar, the disturbance becomes more severe, so steering damping can be increased to desensitize steering.

[0051] FIGS. 4 and 5 are drawings for explaining how to calculate a first steering damping upward rate according to the groove direction of the road surface and the groove direction of the tire according to one embodiment.

[0052] Referring to FIG. 4, the control unit (130) can calculate a first steering damping upward rate greater than or equal to a first reference value when the groove direction of the road surface matches the groove direction of the tire mounted on the vehicle.

[0053] Specifically, FIG. 4 shows that the contact surface between the tire and the road surface is represented as a circle, and that the direction of the tire's grooves matches the direction of the road surface's grooves. When the direction of the tire's grooves matches the direction of the road surface's grooves, the control unit (130) can calculate the first steering damping upward rate to be greater than or equal to the first reference value because the disturbance is intensified.

[0054] Here, whether the direction of the tire grooves and the direction of the road grooves coincide can be determined by the angle formed by the straight line forming the tire grooves and the straight line forming the road grooves, as shown in FIG. 4. Even if the angle formed by each straight line is not zero, if it is within a specific angle, the control unit (130) can determine that the direction of the tire grooves and the direction of the road grooves coincide. This specific angle may vary depending on the component configuration of the steering system and the surrounding driving environment.

[0055] Referring to FIG. 5, the control unit (130) can calculate a first steering damping upward rate greater than a second reference value when the angle formed between the groove direction of the road surface and the groove direction of the tire mounted on the vehicle is greater than a predetermined angle.

[0056] As described above, the control unit (130) determines the first steering damping upward rate through the angle formed by the straight line forming the groove of the tire and the straight line forming the groove of the road surface, and the predetermined angle here may be, for example, 90 degrees. In one embodiment, when the straight line forming the groove of the tire and the straight line forming the groove of the road surface form a 90-degree angle, the disturbance is more severe than when a diagonal 45-degree angle is formed or when the direction of each straight line is aligned at 0 degrees; therefore, the control unit (130) can calculate the first steering damping upward rate to be greater than or equal to the second reference value when the straight line forming the groove of the tire and the straight line forming the groove of the road surface form an orthogonal angle. In addition, even if the aforementioned straight lines do not form an orthogonal angle, i.e., 90 degrees, if they are formed within a specific angle from 90 degrees, the control unit (130) can calculate the first steering damping upward rate to be greater than or equal to the second reference value.

[0057] In one example, the control unit (130) can calculate the first steering damping upward rate to be greater than or equal to the third reference value when the spacing between the tire grooves and the road surface grooves is within a predetermined spacing and the angle formed between the straight line forming the tire grooves and the straight line forming the road surface grooves is 90 degrees. In addition, the third reference value may be greater than the first steering damping upward rate than the second reference value, and the second reference value may be greater than the first steering damping upward rate than the first reference value.

[0058] The control unit (130) can classify the detected column torque into multiple stages and calculate a second steering damping upward rate based on the classified stages.

[0059] To explain in detail with reference to [Table 1] below,

[0060] [Table 1]

[0061]

[0062] In one embodiment, the control unit (130) can classify the detected column torque into four stages.

[0063] The control unit (130) can determine the degree of gripping the driver's steering wheel to determine the driver's steering intention based on the column torque value. Therefore, it can be determined that the greater the detected column torque, the higher the steering wheel grip strength, and if the driver's steering wheel grip strength is high, it can be determined that the driver has a steering intention. Additionally, the control unit (130) can determine whether the driver is steering strongly or weakly based on the strength of the column torque in the driver's steering intention.

[0064] According to the aforementioned [Table 1], the column torque stages can be classified into four, but based on the change in the final steering damping upward rate, the control unit (130) can classify the column torque into three stages.

[0065] The control unit (130) can calculate a second steering damping upward rate so that the first steering damping upward rate is maintained when the column torque is classified into the first stage. Referring to [Table 1], for example, the control unit (130) can calculate a second steering damping upward rate so that the result of the final steering damping upward rate is the first steering damping upward rate when the column torque is less than 0.6.

[0066] The control unit (130) can calculate a second steering damping upward rate such that a weight is applied to the first steering damping upward rate when the column torque is classified into a second stage.

[0067] The control unit (130) can adjust the second steering damping upward rate so that the first steering damping upward rate is not reflected when the column torque is classified into the third stage.

[0068] In one embodiment, the control unit (130) can calculate the final steering damping upward rate by multiplying the first steering damping upward rate and the second steering damping upward rate. Accordingly, when the column torque is classified into three stages to calculate the second steering damping upward rate, the second steering damping upward rate can be calculated as 1 in the first stage of the column torque, and the second steering damping upward rate can be calculated as 0 in the third stage.

[0069] This control unit (130) can be implemented as an Electronic Controller Unit (ECU), a microcomputer, etc.

[0070] In one embodiment, a computer system (not shown), such as a control unit (130), may be implemented as an Electronic Control Unit (ECU). The Electronic Control Unit may include at least one element among one or more processors, memory, storage, user interface input, and user interface output, and these may communicate with each other via a bus. Additionally, the computer system may also include a network interface for connecting to a network. The processor may be a CPU or a semiconductor device that executes processing instructions stored in memory and / or storage. The memory and storage may include various types of volatile / non-volatile storage media. For example, the memory may include ROM and RAM.

[0071] Hereinafter, a steering control method using a steering control device (10) capable of performing all of the above-described disclosures will be described.

[0072] FIG. 6 is a flowchart illustrating a steering control method according to one embodiment of the present disclosure.

[0073] Referring to FIG. 6, the steering control method according to the present disclosure may include a sensor information receiving step (S610) for detecting a groove in the road surface located in the lane of travel of the vehicle and detecting column torque in the steering column, a first steering damping upward rate calculation step (S620) for calculating a first steering damping upward rate based on the detected groove in the road surface, a second steering damping upward rate calculation step (S630) for calculating a second steering damping upward rate based on the column torque detected in the steering column, and a control signal generation step (S640) for calculating a final steering damping upward rate based on the first steering damping upward rate and the second steering damping upward rate, and generating a control signal for applying the calculated final steering damping upward rate.

[0074] FIG. 7 is a flowchart illustrating the calculation of a first steering damping upward rate according to one embodiment.

[0075] The steering control device (10) can obtain road surface information by detecting grooves in the road surface (S710). The steering control device (10) can obtain road surface information by detecting grooves in the road surface located in the vehicle's driving lane through an image sensor, radar sensor, lidar sensor, infrared sensor, etc. mounted on the vehicle.

[0076] The steering control device (10) can determine whether the angle formed by the direction of the tire groove and the direction of the road surface groove is greater than or equal to a predetermined angle (S720). The steering control device (10) can select one of a plurality of grooves formed in a certain direction on the tire and the road surface, calculate a straight line connecting the grooves, and calculate the angle formed by each straight line.

[0077] If the angle formed by the direction of the tire groove and the direction of the road surface groove is greater than or equal to a predetermined angle (Yes of S720), the steering control device (10) can determine whether the spacing between the tire groove and the spacing between the road surface groove is less than or equal to a predetermined spacing (S730).

[0078] When the spacing between the tire grooves and the spacing between the road surface grooves is less than or equal to a predetermined spacing (Yes of S730), the steering control device (10) can calculate the first steering damping upward rate greater than the third reference value (S740). For example, when the angle formed by the tire groove direction and the road surface groove direction is 90 degrees, the disturbance is intensified, and when the spacing between the tire grooves and the road surface grooves is similar, the steering control device (10) can calculate the third reference value, which is a higher reference value due to the intensification of the disturbance.

[0079] When the angle formed by the direction of the tire groove and the direction of the road surface groove is less than a predetermined angle (No. of S720), the steering control device (10) can calculate a first steering damping upward rate greater than or equal to a first reference value (S750). For example, when calculated as 45 degrees or 0 degrees, the first steering damping upward rate can be calculated greater than or equal to a first reference value.

[0080] When the spacing between the grooves of the tire and the spacing between the grooves of the road surface exceeds a predetermined spacing (No. of S730), the steering control device (10) can calculate a first steering damping upward rate greater than or equal to a second reference value.

[0081] Each of the aforementioned reference values ​​cannot calculate an upward rate greater than the upper reference value. For example, if the first steering damping upward rate is calculated greater than the first reference value, the first steering damping upward rate cannot be calculated greater than the second reference value. Likewise, if the first steering damping upward rate is calculated greater than the second reference value, the first steering damping upward rate cannot be calculated greater than the third reference value.

[0082] FIG. 8 is a flowchart illustrating the calculation of a second steering damping upward rate according to one embodiment.

[0083] Referring to FIG. 8, the steering control device (10) can obtain column torque (S810). The steering control device (10) can obtain column torque generated in the steering column by detecting it through a torque sensor.

[0084] The steering control device (10) can determine whether the acquired column torque is included in the third stage among the stages classified into multiple stages (S820).

[0085] If the detected column torque is at the third stage (Yes in S820), the steering control device (10) can calculate a second steering damping upward rate so that the first steering damping upward rate is not reflected (S830). In one embodiment, when the final steering damping upward rate is calculated as the product of the first steering damping upward rate and the second steering damping upward rate, the second steering damping upward rate can be calculated as 0.

[0086] If the detected column torque is not in the third stage (No of S820), the steering control device (10) can determine whether the detected column torque is in the second stage (S840).

[0087] If the detected column torque is at the second stage (Yes in S840), the steering control device (10) can calculate a second steering damping upward rate such that a weight is applied to the first steering damping upward rate (S850).

[0088] If the detected column torque is not at the second stage (No. 820), the steering control device (10) can calculate a second steering damping upward rate so that the first steering damping upward rate is maintained (S860). For example, when the final steering damping upward rate is calculated as described above, the second steering damping upward rate can be calculated as 1.

[0089] As described above, according to the present disclosure, a steering control device and method can be provided to mitigate a target steering angle by desensitizing steering changes under specific road surface conditions.

[0090] The foregoing description is merely an illustrative explanation of the technical concept of the present disclosure, and those skilled in the art to which the present disclosure pertains may make various modifications and variations within the scope of the essential characteristics of the technical concept. Furthermore, since these embodiments are intended to explain, not limit, the scope of the technical concept is not limited by these embodiments. The scope of protection of the present disclosure shall be interpreted by the claims below, and all technical concepts within an equivalent scope shall be interpreted as being included within the scope of rights of the present disclosure. Explanation of the symbols

[0092] 10: Steering control unit 110: Road surface groove detection unit 120: Torque detection unit 130: Control unit

Claims

Claim 1 A steering control device comprising: a road surface groove detection unit for detecting grooves on the road surface located in the lane of travel of a vehicle; a torque detection unit for detecting column torque in a steering column; and a control unit for calculating a first steering damping upward rate based on the detected grooves on the road surface, calculating a second steering damping upward rate based on the column torque detected in the steering column, calculating a final steering damping upward rate based on the first steering damping upward rate and the second steering damping upward rate, and generating a control signal for applying the calculated final steering damping upward rate. Claim 2 In claim 1, the control unit is a steering control device that calculates a first steering damping upward rate greater than or equal to a first reference value when the groove spacing formed on the road surface is detected to be within a predetermined range with respect to the groove spacing of a tire mounted on a vehicle. Claim 3 In claim 1, the control unit is a steering control device that calculates the first steering damping upward rate greater than or equal to the first reference value when the groove direction of the road surface matches the groove direction of the tire mounted on the vehicle. Claim 4 In claim 1, the control unit is a steering control device that calculates the first steering damping upward rate greater than or equal to the second reference value when the angle formed by the groove direction of the road surface with the groove direction of the tire mounted on the vehicle is greater than or equal to a predetermined angle. Claim 5 A steering control device according to claim 1, wherein the control unit classifies the detected column torque into a plurality of stages and calculates the second steering damping upward rate based on the classified stages. Claim 6 In claim 5, the control unit is a steering control device that calculates a second steering damping upward rate so as to maintain the first steering damping upward rate when the column torque is classified into a first stage. Claim 7 In claim 5, the control unit is a steering control device that calculates a second steering damping upward rate such that a weight is applied to the first steering damping upward rate when the column torque is classified into a second stage. Claim 8 In claim 5, the control unit is a steering control device that calculates a second steering damping upward rate so that the first steering damping upward rate is not reflected when the column torque is classified into a third stage. Claim 9 In claim 1, the control unit is a steering control device that calculates the final steering damping upward rate as the product of the first steering damping upward rate and the second steering damping upward rate. Claim 10 A steering control method comprising: a sensor information receiving step for detecting grooves in the road surface located in the lane of travel of a vehicle and detecting column torque in a steering column; a first steering damping upward rate calculation step for calculating a first steering damping upward rate based on the detected grooves in the road surface; a second steering damping upward rate calculation step for calculating a second steering damping upward rate based on the column torque detected in the steering column; and a control signal generation step for calculating a final steering damping upward rate based on the first steering damping upward rate and the second steering damping upward rate, and generating a control signal for applying the calculated final steering damping upward rate. Claim 11 In claim 10, the first steering damping upward rate calculation step is a steering control method that calculates the first steering damping upward rate greater than or equal to a first reference value when the groove spacing formed on the road surface is detected to be within a predetermined range with respect to the groove spacing of the tire mounted on the vehicle. Claim 12 In claim 10, the first steering damping upward rate calculation step is a steering control method that calculates the first steering damping upward rate to be greater than or equal to a first reference value when the groove direction of the road surface matches the groove direction of the tire mounted on the vehicle. Claim 13 In claim 10, the first steering damping upward rate calculation step is a steering control method that calculates the first steering damping upward rate to be greater than or equal to a second reference value when the angle formed by the groove direction of the road surface and the groove direction of the tire mounted on the vehicle is greater than or equal to a predetermined angle. Claim 14 In claim 10, the second steering damping upward rate calculation step is a steering control method that classifies the detected column torque into a plurality of stages and calculates the second steering damping upward rate based on the classified stages. Claim 15 In claim 14, the second steering damping upward rate calculation step is a steering control method that calculates the second steering damping upward rate so that the first steering damping upward rate is maintained when the column torque is classified into the first stage. Claim 16 In claim 14, the second steering damping upward rate calculation step is a steering control method that calculates the second steering damping upward rate such that a weight is applied to the first steering damping upward rate when the column torque is classified into the second stage. Claim 17 In claim 14, the second steering damping upward rate calculation step is a steering control method that calculates the second steering damping upward rate so that the first steering damping upward rate is not reflected when the column torque is classified into the third stage. Claim 18 In claim 10, the control signal generation step is a steering control method that calculates the final steering damping upward rate by multiplying the first steering damping upward rate and the second steering damping upward rate.

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