KR20190141967A - Steering control method for rear wheel steering - Google Patents

Steering control method for rear wheel steering Download PDF

Info

Publication number
KR20190141967A
KR20190141967A KR1020180068850A KR20180068850A KR20190141967A KR 20190141967 A KR20190141967 A KR 20190141967A KR 1020180068850 A KR1020180068850 A KR 1020180068850A KR 20180068850 A KR20180068850 A KR 20180068850A KR 20190141967 A KR20190141967 A KR 20190141967A
Authority
KR
South Korea
Prior art keywords
wheel speed
wheel
speed
confidence interval
steering
Prior art date
Application number
KR1020180068850A
Other languages
Korean (ko)
Other versions
KR102575395B1 (en
Inventor
정장현
Original Assignee
현대자동차주식회사
기아자동차주식회사
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 현대자동차주식회사, 기아자동차주식회사 filed Critical 현대자동차주식회사
Priority to KR1020180068850A priority Critical patent/KR102575395B1/en
Publication of KR20190141967A publication Critical patent/KR20190141967A/en
Application granted granted Critical
Publication of KR102575395B1 publication Critical patent/KR102575395B1/en

Links

Images

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B62LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62DMOTOR VEHICLES; TRAILERS
    • B62D7/00Steering linkage; Stub axles or their mountings
    • B62D7/06Steering linkage; Stub axles or their mountings for individually-pivoted wheels, e.g. on king-pins
    • B62D7/14Steering linkage; Stub axles or their mountings for individually-pivoted wheels, e.g. on king-pins the pivotal axes being situated in more than one plane transverse to the longitudinal centre line of the vehicle, e.g. all-wheel steering
    • B62D7/15Steering linkage; Stub axles or their mountings for individually-pivoted wheels, e.g. on king-pins the pivotal axes being situated in more than one plane transverse to the longitudinal centre line of the vehicle, e.g. all-wheel steering characterised by means varying the ratio between the steering angles of the steered wheels
    • B62D7/159Steering linkage; Stub axles or their mountings for individually-pivoted wheels, e.g. on king-pins the pivotal axes being situated in more than one plane transverse to the longitudinal centre line of the vehicle, e.g. all-wheel steering characterised by means varying the ratio between the steering angles of the steered wheels characterised by computing methods or stabilisation processes or systems, e.g. responding to yaw rate, lateral wind, load, road condition
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60WCONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
    • B60W10/00Conjoint control of vehicle sub-units of different type or different function
    • B60W10/20Conjoint control of vehicle sub-units of different type or different function including control of steering systems
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60WCONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
    • B60W40/00Estimation or calculation of non-directly measurable driving parameters for road vehicle drive control systems not related to the control of a particular sub unit, e.g. by using mathematical models
    • B60W40/10Estimation or calculation of non-directly measurable driving parameters for road vehicle drive control systems not related to the control of a particular sub unit, e.g. by using mathematical models related to vehicle motion
    • B60W40/105Speed
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B62LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62DMOTOR VEHICLES; TRAILERS
    • B62D15/00Steering not otherwise provided for
    • B62D15/02Steering position indicators ; Steering position determination; Steering aids
    • B62D15/021Determination of steering angle
    • B62D15/024Other means for determination of steering angle without directly measuring it, e.g. deriving from wheel speeds on different sides of the car
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B62LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62DMOTOR VEHICLES; TRAILERS
    • B62D6/00Arrangements for automatically controlling steering depending on driving conditions sensed and responded to, e.g. control circuits
    • B62D6/002Arrangements for automatically controlling steering depending on driving conditions sensed and responded to, e.g. control circuits computing target steering angles for front or rear wheels
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60YINDEXING SCHEME RELATING TO ASPECTS CROSS-CUTTING VEHICLE TECHNOLOGY
    • B60Y2400/00Special features of vehicle units
    • B60Y2400/84Rear wheel steering; All wheel steerings

Landscapes

  • Engineering & Computer Science (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Physics & Mathematics (AREA)
  • Mathematical Physics (AREA)
  • Theoretical Computer Science (AREA)
  • Automation & Control Theory (AREA)
  • Steering Control In Accordance With Driving Conditions (AREA)
  • Steering-Linkage Mechanisms And Four-Wheel Steering (AREA)

Abstract

The present invention relates to a technology for stably controlling rear wheel steering of a vehicle by diagnosing an error and an abnormality of a wheel speed. According to the present invention, disclosed is a rear wheel steering control method, which determines not only the abnormality of a wheel speed but also the error by detecting the error of a wheel speed by analyzing the wheel speed statistically and stably performs rear wheel steering control by excluding the wheel speed when an error occurs and an abnormality of the wheel speed occurs and estimating a vehicle speed based on a normal wheel speed.

Description

후륜 조향 제어방법{STEERING CONTROL METHOD FOR REAR WHEEL STEERING}Rear wheel steering control method {STEERING CONTROL METHOD FOR REAR WHEEL STEERING}

본 발명은 휠속도의 오류 및 이상 여부를 진단하여 차량의 후륜 조향을 안정적으로 제어하는 후륜 조향 제어방법에 관한 것이다.The present invention relates to a rear wheel steering control method for stably controlling rear wheel steering of a vehicle by diagnosing errors and abnormalities in wheel speed.

차량이 고속으로 주행하는 경우에는 조향각이 작아도 되지만, 주차시 또는 급커브를 저속으로 선회하는 경우에는 조향각이 상대적으로 커야 한다.The steering angle may be small when the vehicle is traveling at a high speed, but the steering angle should be relatively large when parking or turning a sharp curve at low speed.

다만, 전륜과 함께 후륜을 조향시키는 4륜 조향(4-wheel steering : 4WS)방식의 경우, 2륜 조향(2-wheel steering : 2WS)방식에 비해 회전반경을 작게 할 수 있음은 물론, 선회 안정성을 크게 향상시킬 수 있게 된다.However, in the case of the 4-wheel steering (4WS) system that steers the rear wheel together with the front wheel, the turning radius can be reduced as well as the turning stability compared to the 2-wheel steering (2WS) system. It can be greatly improved.

즉, 4륜 조향 방식의 경우, 저속에서는 후륜 조향각을 전륜 조향각에 대해 반대방향인 역위상으로 제어함으로써 회전반경을 축소시키게 되고, 또한 고속에서는 후륜 조향각을 전륜 조향각과 같은 방향인 동위상으로 제어함으로써 주행 안정성을 향상시키게 된다.That is, in the case of the four-wheel steering method, the rotation radius is reduced by controlling the rear wheel steering angle to the reverse phase opposite to the front wheel steering angle at low speed, and at the high speed, the rear wheel steering angle is controlled to the same phase in the same direction as the front wheel steering angle. The driving stability is improved.

예컨대, 4개 휠의 휠속도를 측정하고, 이들 휠속도의 평균값을 차속으로 간주하여 차속별로 후륜의 동역상 조향비를 연산한다.For example, the wheel speeds of four wheels are measured, and the average steering wheel speed is regarded as the vehicle speed, and the dynamic steering ratio of the rear wheels is calculated for each vehicle speed.

그런데, 휠은 회전하는데 차속에 반영이 안되는 휠 슬립이 발생하거나, 반대로 휠은 회전하지 않는데 차속이 발생하는 휠 록킹 상황이 발생하는 경우, 추정된 차속과 실제 차속의 차이가 발생함으로써, 동역상 조향비 제어에 오류가 발생하는 문제가 있다.By the way, when the wheel is rotated, but the wheel slip occurs that is not reflected in the vehicle speed, or conversely, when the wheel locking situation occurs when the wheel does not rotate, but the vehicle speed is generated, the difference between the estimated vehicle speed and the actual vehicle speed occurs, so that steering There is a problem that an error occurs in the non-control.

상기의 배경기술로서 설명된 사항들은 본 발명의 배경에 대한 이해 증진을 위한 것일 뿐, 이 기술분야에서 통상의 지식을 가진 자에게 이미 알려진 종래기술에 해당함을 인정하는 것으로 받아들여져서는 안 될 것이다.The matters described as the background art are only for the purpose of improving the understanding of the background of the present invention, and should not be taken as acknowledging that they correspond to the related art already known to those skilled in the art.

KR 10-2008-0019786 AKR 10-2008-0019786 A

본 발명은 전술한 바와 같은 문제점을 해결하기 위하여 안출한 것으로, 휠속도의 오류 및 이상 여부를 진단하여 차량의 후륜 조향을 안정적으로 제어하는 후륜 조향 제어방법을 제공하는 데 있다.The present invention has been made to solve the above problems, and to provide a rear wheel steering control method for stably controlling the rear wheel steering of the vehicle by diagnosing errors and abnormalities of the wheel speed.

상기와 같은 목적을 달성하기 위한 본 발명의 구성은, 컨트롤러에 각각 측정된 휠속도가 입력되는 휠속도입력단계; 컨트롤러가 미리 확보된 휠속도데이터를 이용하여 각각의 휠속도평균값에 대한 통계적 신뢰구간을 설정하는 신뢰구간설정단계; 및 컨트롤러는 상기 휠속도가 상기 신뢰구간을 이탈하는 경우, 신뢰구간을 이탈한 휠속도를 제외한 나머지 휠속도를 기준으로 차속을 추정하여 후륜의 조향 작동을 제어하는 제1페일세이프단계;를 포함하는 것을 특징으로 할 수 있다.The configuration of the present invention for achieving the above object, the wheel speed input step of inputting the measured wheel speed respectively to the controller; A confidence interval setting step of setting, by the controller, a statistical confidence interval for each wheel speed average value using the wheel speed data secured in advance; And a controller, when the wheel speed deviates from the confidence interval, estimating the vehicle speed based on the remaining wheel speed except for the wheel speed deviating from the confidence interval to control steering operation of the rear wheel. It may be characterized by.

상기 신뢰구간설정단계 이 후에, 각각의 휠속도 모두가 신뢰구간을 이탈하는지 판단하는 휠속도판단단계;를 더 포함할 수 있다.After the confidence interval setting step, the wheel speed determination step of determining whether each wheel speed is out of the confidence interval; may further include.

상기 휠속도판단단계의 판단 결과, 각각의 휠속도 모두가 신뢰구간을 이탈하는 경우, 전체 휠속도평균값과 소정값 이상 차이가 발생하는 휠속도를 제외한 나머지 휠속도를 기준으로 차속을 추정하여 후륜의 조향 작동을 제어하는 제2페일세이프단계;를 더 포함할 수 있다.As a result of the determination of the wheel speed determination step, when all of the wheel speeds deviate from the confidence interval, the vehicle speed is estimated based on the remaining wheel speeds except the wheel speed at which the difference between the overall wheel speed average value and a predetermined value or more occurs. The second fail-safe step of controlling the steering operation may further include.

상기 제2페일세이프단계는, 차량의 종가속도를 판단하고; 상기 종가속도가 0 이상인 경우, 전체 휠속도평균값보다 큰 휠속도를 제외한 나머지 휠속도를 기준으로 차속을 추정하며; 상기 종가속도가 0 미만인 경우, 전체 휠속도평균값보다 작은 휠속도를 제외한 나머지 휠속도를 기준으로 차속을 추정할 수 있다.The second fail safe step may include determining a longitudinal acceleration of the vehicle; When the longitudinal acceleration is equal to or greater than 0, estimating a vehicle speed based on the remaining wheel speed except for a wheel speed larger than an average of the total wheel speed; When the longitudinal acceleration is less than zero, the vehicle speed may be estimated based on the remaining wheel speeds excluding the wheel speed smaller than the average wheel speed average value.

상기 휠속도가 신뢰구간을 이탈한 경우, 휠속도가 이탈 직전 휠속도 대비하여 기준율 이상이고, 일정시간 이상 지속시, 후륜을 중립으로 이동하여 후륜 조향을 실시하지 않도록 제어하는 제3페일세이프단계;를 더 포함할 수 있다.A third fail-safe step of controlling not to perform rear wheel steering by moving the rear wheel to neutral when the wheel speed is greater than the reference ratio compared to the wheel speed immediately before the departure, when the wheel speed is out of the confidence interval; It may further include.

상기 휠속도가 상기 신뢰구간을 이탈한 후에, 각각의 휠속도 중 최고 휠속도와 최저 휠속도 차이가 설정속도 이하인 경우, 전체 휠속도를 기준으로 차속을 추정하여 후륜의 조향 작동을 제어하는 정상제어단계;를 더 포함할 수 있다.After the wheel speed deviates from the confidence interval, when the difference between the highest wheel speed and the lowest wheel speed among the respective wheel speeds is less than or equal to the set speed, the normal control of estimating the vehicle speed based on the total wheel speed to control the steering operation of the rear wheels. Steps may further include.

상기한 과제 해결수단을 통해 본 발명은, 휠속도를 통계적으로 분석하여 휠속도의 오류를 검출함으로써, 휠속도의 이상 여부 뿐 아니라 오류 여부까지도 판단할 수 있는 효과가 있고, 더불어 휠속도의 오류 및 이상 발생시 오류가 발생한 휠속도를 배제하고 정상적인 휠속도를 기반으로 차속을 추정하여 후륜을 조향함으로써, 후륜 조향 제어가 안정적으로 이루어질 수 있는 효과가 있다.The present invention through the above problem solving means, by analyzing the wheel speed statistically to detect the error of the wheel speed, there is an effect that can determine not only whether the wheel speed is abnormal, but also the error, and also the error of the wheel speed and When an error occurs, the rear wheel steering is performed by excluding the wheel speed in which an error occurs and estimating the vehicle speed based on the normal wheel speed, so that the rear wheel steering control can be stably performed.

도 1은 본 발명에 적용되는 차량과 컨트롤러의 구성을 개략적으로 예시한 도면.
도 1은 본 발명의 휠속도 오류 검출에 따른 조향 제어과정을 순차적으로 도시한 흐름도.
도 2 및 도 3은 4개의 휠 중 어느 한 휠의 휠속도평균값에 대한 신뢰수준 및 신뢰구간을 설정하는 원리를 설명하기 위한 도면.
도 4는 차량의 여러 주행 상황에서 휠속도 오류 발생시의 휠속도 거동을 예시하여 나타낸 도면.
1 is a view schematically illustrating the configuration of a vehicle and a controller applied to the present invention.
1 is a flowchart sequentially illustrating a steering control process according to the wheel speed error detection of the present invention.
2 and 3 are diagrams for explaining the principle of setting the confidence level and confidence interval for the wheel speed average value of any one of the four wheels.
4 is a diagram illustrating wheel speed behavior when a wheel speed error occurs in various driving situations of a vehicle.

본 발명의 바람직한 실시예를 첨부된 도면에 의하여 상세히 설명하면 다음과 같다.When described in detail with reference to the accompanying drawings a preferred embodiment of the present invention.

본 발명은 차량의 4개 휠속도에 대한 오류 및 이상 여부를 휠속도데이터의 통계적 신뢰수준을 이용하여 검출하고, 검출된 결과를 바탕으로 후륜 조향 제어를 안전하게 실시하도록 제어하는 로직에 관한 것이다.The present invention relates to logic for detecting errors and abnormalities of four wheel speeds of a vehicle using statistical confidence levels of wheel speed data, and safely performing rear wheel steering control based on the detected results.

도 1 및 도 2를 참조하여, 상기한 후륜 조향 제어를 위한 본 발명의 제어구성에 대해 설명하면, 먼저 휠속도입력단계에서는 차량에 장착된 4개 휠의 휠속도가 휠속도센서를 통해 각각 측정되고, 측정된 각각의 휠속도가 컨트롤러에 입력된다.1 and 2, the control configuration of the present invention for the rear wheel steering control described above, first, in the wheel speed input step, the wheel speed of the four wheels mounted on the vehicle is measured through the wheel speed sensor, respectively Each measured wheel speed is input to the controller.

신뢰구간설정단계에서는, 상기 컨트롤러가 미리 확보된 휠속도데이터를 이용하여 각각의 휠속도평균값에 대한 통계적 신뢰구간을 설정하게 된다.In the confidence interval setting step, the controller sets the statistical confidence interval for each wheel speed average value by using the wheel speed data secured in advance.

도 3 및 도 4를 참조하여 설명하면, 휠속도가 측정됨에 따라 휠속도평균값이 산출되면, 기존에 확보된 휠속도데이터를 기반으로 휠속도평균값이 존재하는 신뢰구간을 결정할 수 있다.Referring to FIGS. 3 and 4, when the wheel speed average value is calculated as the wheel speed is measured, a confidence interval in which the wheel speed average value exists may be determined based on the wheel speed data previously secured.

여기서, 상기 신뢰구간은 휠속도평균값의 참값이 존재할 것으로 추정되는 구간이고, 신뢰수준은 휠속도평균값의 참값이 신뢰구간 내에 존재할 확률로서, 본 발명에서는 신뢰수준이 99%가 되는 신뢰구간을 설정할 수 있다.Here, the confidence interval is a section in which the true value of the wheel speed average value is estimated to exist, and the confidence level is a probability that the true value of the wheel speed average value exists in the confidence interval. In the present invention, a confidence interval of 99% confidence level can be set. have.

이는, 아래와 같은 정규분포 확률 밀도 함수를 이용하여 구할 수 있다.This can be obtained using the following normal probability density function.

Figure pat00001
Figure pat00001

σ : 표준편차σ: standard deviation

m : 평균m: mean

신뢰수준이 99%가 되는 신뢰구간의 하한값 : m - 2.58 ×σLower bound of the confidence interval where the confidence level is 99%: m-2.58 × σ

신뢰수준이 99%가 되는 신뢰구간의 상한값 : m + 2.58 ×σUpper bound of the confidence interval where the confidence level is 99%: m + 2.58 × σ

즉, 평균(휠속도평균값)이 99% 신뢰수준에서 존재할만한 신뢰구간을 설정하고, 이를 벗어나는 데이터(휠속도)는 오류 또는 이상 징후로 판단하는 것이다.In other words, the mean (wheel speed average value) sets the confidence interval that can exist at the 99% confidence level, and the data (wheel speed) that deviates from this is judged as an error or an abnormality.

계속해서, 도 1 및 도 2를 참조하면, 제1페일세이프단계에서는, 컨트롤러는 상기 휠속도가 상기 신뢰구간을 이탈하는 경우, 신뢰구간을 이탈한 휠속도를 제외한 나머지 휠속도를 기준으로 차속을 추정하여 후륜의 조향 작동을 제어할 수 있다.1 and 2, in the first fail-safe step, when the wheel speed deviates from the confidence interval, the controller determines the vehicle speed based on the remaining wheel speed except for the wheel speed deviating from the confidence interval. Estimation can control steering operation of the rear wheels.

예컨대, 4개의 휠속도 중 전륜 좌측휠의 휠속도가 신뢰구간을 벗어나는 경우, 전륜 좌측휠의 휠속도를 제외한 나머지 3개의 휠속도를 다시 평균하여 차속을 구하고, 새롭게 연산된 차속을 기준으로 후륜의 동역상 조향비를 연산하여 후륜을 조향하게 된다.For example, if the wheel speed of the left wheel out of the four wheel speeds is out of the confidence interval, the vehicle speed is calculated by averaging the remaining three wheel speeds except the wheel speed of the left wheel of the front wheel, and based on the newly calculated vehicle speed, The rear wheels are steered by calculating the steering phase in the dynamic range.

이 같은 구성에 따라, 본 발명은 휠속도 간을 비교하는 방식으로 휠속도의 오류를 검출하는 방식이 아닌, 휠속도를 통계적으로 분석하여 휠속도의 오류를 검출함으로써, 휠속도의 이상 여부 뿐 아니라 오류 여부까지도 판단이 가능하고, 휠속도의 오류 및 이상 발생시 오류가 발생한 휠속도를 배제하고 정상적인 휠속도를 기반으로 차속을 추정하여 후륜을 조향함으로써, 후륜 조향 제어가 안정적으로 이루어질 수 있게 된다.According to this configuration, the present invention is not a method of detecting the error of the wheel speed by comparing the wheel speed, but by analyzing the wheel speed statistically to detect the error of the wheel speed, as well as whether the wheel speed is abnormal It is possible to determine whether or not an error, and by excluding the wheel speed error occurs when the wheel speed error and abnormality, and by estimating the vehicle speed based on the normal wheel speed, the rear wheel steering control can be made stable.

그리고, 본 발명에서는 상기 신뢰구간설정단계 이 후에, 전체의 휠속도 모두가 신뢰구간을 이탈하는지 판단하는 휠속도판단단계를 더 포함할 수 있다.In addition, the present invention may further include a wheel speed determination step of determining whether all the wheel speeds deviate from the confidence interval after the confidence interval setting step.

즉, 상기 휠속도판단단계의 판단 결과, 4개의 휠속도 중 일부의 휠속도가 신뢰구간을 이탈한 경우, 신뢰구간을 이탈한 휠속도를 제외한 나머지 휠속도만으로 차속을 추정하여 후륜을 조향 제어할 수 있다.That is, when the wheel speed determination step determines that the wheel speed of some of the four wheel speeds deviates from the confidence interval, the rear wheel may be steered by estimating the vehicle speed only by the remaining wheel speed except the wheel speed that deviated from the confidence interval. Can be.

다만, 상기 휠속도판단단계의 판단 결과, 전체의 휠속도 모두가 신뢰구간을 이탈하는 경우, 전체 휠속도평균값과 소정값 이상 차이가 발생하는 휠속도를 제외한 나머지 휠속도를 기준으로 차속을 추정하여 후륜의 조향 작동을 제어하는 제2페일세이프단계에 진입하도록 제어할 수 있다.However, as a result of the determination of the wheel speed judging step, when all the wheel speeds deviate from the confidence interval, the vehicle speed is estimated based on the remaining wheel speeds except the wheel speed at which the difference between the overall wheel speed average value and a predetermined value or more occurs. The vehicle may be controlled to enter a second fail-safe step of controlling steering operation of the rear wheels.

즉, 상기 휠속도판단단계의 판단 결과, 4개의 휠속도 모두가 신뢰구간을 이탈한 경우, 4개의 휠속도평균값을 산출한 후, 산출된 4개의 휠속도평균값과 소정값 이상 차이가 발생하는 휠속도를 배제하고, 나머지 휠속도만으로 차속을 추정하게 되는 것이다.That is, as a result of the determination of the wheel speed determination step, when all four wheel speeds deviate from the confidence interval, after calculating four wheel speed average values, the wheels having a difference more than a predetermined value from the calculated four wheel speed average values are generated. It excludes the speed and estimates the vehicle speed only with the remaining wheel speed.

이 같은 상기 제2페일세이프단계는 휠속도의 일시적인 오류가 발생하는 경우의 대처방안으로, 차량의 가속시와 감속시의 상황을 구분하여 제어가 이루어질 수 있다.The second fail-safe step is a countermeasure in the event of a temporary error in the wheel speed. The second fail-safe step may be controlled by dividing a situation during acceleration and deceleration of the vehicle.

예컨대, 차량의 종가속도를 판단하고, 상기 종가속도가 0 이상인 경우, 차량의 가속상황으로 생각할 수 있는바, 이때에는 전체 4개의 휠속도평균값보다 큰 휠속도를 제외하고, 나머지 휠속도를 기준으로 차속을 추정할 수 있다.For example, when the longitudinal acceleration of the vehicle is determined and the longitudinal acceleration is zero or more, it may be considered as an acceleration situation of the vehicle. In this case, except for wheel speeds larger than the average of all four wheel speeds, the remaining wheel speed is based on the remaining wheel speed. The vehicle speed can be estimated.

반면, 상기 종가속도가 0 미만인 경우에는, 감속상황으로 생각할 수 있는바, 이때에는 전체 4개의 휠속도평균값보다 작은 휠속도를 제외하고, 나머지 휠속도를 기준으로 차속을 추정할 수 있다.On the other hand, when the longitudinal acceleration is less than zero, it can be considered as a deceleration situation. In this case, the vehicle speed may be estimated based on the remaining wheel speeds except for wheel speeds smaller than the average of four wheel speeds.

즉, 차량의 급가속, 급감속, 빙판길 등의 경우, 일시적으로 휠스핀 휠락 상황이 발생할 수 있으므로, 일시적으로 오류가 발생한 휠속도를 배제하고 나머지 휠속도를 이용하여 차속을 추정함으로써, 후륜의 조향이 보다 안정적으로 이루어질 수 있게 된다.That is, in the case of rapid acceleration, sudden deceleration, and icy road of the vehicle, a wheel spin wheel lock situation may occur temporarily. Therefore, the wheel speed may be estimated by using the remaining wheel speed by excluding the wheel speed that has temporarily failed. Steering can be made more stable.

아울러, 본 발명은 상기 휠속도가 신뢰구간을 이탈한 경우, 이탈 직전 휠속도 대비하여 기준율 이상이고, 일정시간 이상 지속시, 후륜을 중립으로 이동하여 후륜 조향을 실시하지 않도록 제어하는 제3세이프티단계를 더 포함할 수 있다.In addition, the present invention, when the wheel speed is out of the confidence interval, the third safety step to control not to perform the rear wheel steering by moving the rear wheel to neutral when the wheel speed is more than the reference ratio compared to the speed of the wheel immediately before the departure, and for a predetermined time or more It may further include.

즉, 휠속도가 신뢰구간을 벗어난 시간이 일정 시간 이상 지속되는 경우, 이는 일시적인 오류가 아닌 휠속도센서의 고장 상황 등으로 생각해볼 수 있는바, 이 경우 후륜을 온센터인 중립위치로 이동시킨 후, 후륜 조향을 실시하지 않도록 제어하게 되는 것이다.In other words, if the wheel speed is out of the confidence interval for more than a certain time, it can be thought of as a fault condition of the wheel speed sensor, not a temporary error.In this case, after moving the rear wheel to the neutral position, which is on center Therefore, control is performed so that rear wheel steering is not performed.

한편, 상기 휠속도가 상기 신뢰구간을 이탈한 후에, 각각의 휠속도 중 최고 휠속도와 최저 휠속도 차이가 설정속도 이하인 경우, 전체 휠속도를 기준으로 차속을 추정하여 후륜의 조향 작동을 제어하는 정상제어단계를 더 포함할 수 있다.On the other hand, after the wheel speed is out of the confidence interval, if the difference between the highest wheel speed and the lowest wheel speed of each of the wheel speed is less than the set speed, to estimate the vehicle speed based on the total wheel speed to control the steering operation of the rear wheel It may further comprise a normal control step.

예컨대, 제1세이프티단계를 통해 오류가 발생한 휠속도를 배제하여 차속을 추정한 후에, 4개의 휠속도를 측정하여, 이들 중에서 가장 큰 휠속도와 가장 작은 휠속도의 차이가 설정된 속도 이하이면, 휠속도 모두를 정상으로 인지하여 4개의 휠속도를 이용하여 차속을 연산하고, 연산된 차속을 기반으로 후륜을 조향 제어할 수 있다.For example, after estimating the vehicle speed by excluding an errored wheel speed through the first safety step, four wheel speeds are measured, and if the difference between the largest wheel speed and the smallest wheel speed is less than or equal to the set speed, the wheel Recognizing all speeds as normal, the vehicle speed may be calculated using the four wheel speeds, and the rear wheel may be controlled based on the calculated vehicle speed.

도 2를 참조하여, 본 발명에 따른 후륜 조향 제어과정을 순차적으로 설명하면, 4개 휠의 휠속도를 각각 측정하고(S10), 측정된 휠속도를 기반으로 각 휠속도평균값을 구한 후, 각 휠속도평균값에 대한 통계적 신뢰구간을 설정한다(S20).Referring to Figure 2, in order to sequentially explain the rear wheel steering control process according to the invention, the wheel speed of each of the four wheels are measured (S10), each wheel speed average value is calculated based on the measured wheel speed, Set a statistical confidence interval for the wheel speed average value (S20).

그리고, 각각의 휠속도가 상기 신뢰구간을 이탈하는지 판단하고(S30), 판단 결과 신뢰구간을 이탈한 휠속도가 있는 경우, 신뢰구간을 이탈한 휠속도가 이탈 직전 휠속도 대비하여 A % 이상 변동되고, 그 상승된 상태가 B sec 이상 지속되는지 판단한다(S40).Then, it is determined whether each wheel speed deviates from the confidence interval (S30), and when the determination result is that the wheel speed deviates from the confidence interval, the wheel speed deviating from the confidence interval varies by more than A% compared to the wheel speed immediately before departure. Then, it is determined whether the elevated state lasts for more than B sec (S40).

S40단계의 판단 결과, 휠속도의 변동이 A % 이상이고, B sec 이상 지속되는 경우, 후륜을 중립으로 이동하여 후륜 조향을 실시하지 않도록 제어하게 된다(S50).As a result of the determination in step S40, if the change in the wheel speed is more than A%, and persists for more than B sec, the rear wheel is moved to neutral to control not to perform rear wheel steering (S50).

다만, S40단계의 판단 결과, 휠속도의 변동이 크지 않거나 변동시간이 일정시간 이상 지속되지 않는 경우, 4개의 휠속도 모두가 신뢰구간을 벗어났는지 판단한다(S60).However, as a result of the determination in step S40, if the variation in the wheel speed is not large or the variation time does not last for a predetermined time, it is determined whether all four wheel speeds are out of the confidence interval (S60).

S60단계의 판단 결과, 4개의 휠속도 중 일부의 휠속도가 신뢰구간을 벗어난 경우, 신뢰구간을 이탈한 휠속도를 제외하고, 나머지 휠속도를 재평균하여 차속을 구한후, 연산된 차속을 기준으로 후륜을 조향 제어하게 된다(S70).As a result of the determination in step S60, when some of the wheel speeds out of the four wheel speeds are out of the confidence interval, the vehicle speed is obtained by re-averaging the remaining wheel speeds, except for the wheel speed that is out of the confidence interval, and then based on the calculated vehicle speed. By controlling the rear wheel (S70).

반면, S60단계의 판단 결과, 4개의 휠속도 모두가 신뢰구간을 벗어난 경우, 차량의 종가속도를 판단한다(S80).On the other hand, when the determination result of step S60, all four wheel speeds out of the confidence interval, it determines the longitudinal acceleration of the vehicle (S80).

판단 결과, 종가속도가 0 이상인 경우, 전체 휠속도평균값보다 큰 휠속도를 제외한 나머지 휠속도를 기준으로 차속을 구하여 연산된 차속을 기준으로 후륜을 조향 제어하고(S90), 종가속도가 0 미만인 경우, 전체 휠속도평균값보다 작은 휠속도를 제외한 나머지 휠속도를 기준으로 차속을 구하여 연산된 차속을 기준으로 후륜을 조향 제어한다(S100).As a result of the determination, when the closing acceleration is zero or more, the steering wheel is controlled based on the calculated vehicle speed by calculating the vehicle speed based on the remaining wheel speed except the wheel speed larger than the average of the total wheel speed (S90), and when the closing acceleration is less than zero. In operation S100, steering of the rear wheel is performed based on the calculated vehicle speed by obtaining the vehicle speed based on the remaining wheel speed except for the wheel speed smaller than the average wheel speed.

상술한 바와 같이, 본 발명은 휠속도 간을 비교하는 방식으로 휠속도의 오류를 검출하는 방식이 아닌, 휠속도를 통계적으로 분석하여 휠속도의 오류를 검출함으로써, 휠속도의 이상 여부 뿐 아니라 오류 여부까지도 판단이 가능하고, 또한 휠속도의 오류 및 이상 발생시 오류가 발생한 휠속도를 배제하고 정상적인 휠속도를 기반으로 차속을 추정하여 후륜을 조향함으로써, 후륜 조향 제어가 안정적으로 이루어질 수 있게 된다.As described above, the present invention is not a method of detecting the error of the wheel speed by comparing the wheel speed, but by analyzing the wheel speed statistically to detect the error of the wheel speed, as well as whether the wheel speed is abnormal or not. It is possible to determine whether or not, and also, by excluding the wheel speed in which an error and an error occur in the wheel speed and estimating the vehicle speed based on the normal wheel speed, the rear wheel steering control can be stably performed.

한편, 본 발명은 상기한 구체적인 예에 대해서만 상세히 설명되었지만 본 발명의 기술사상 범위 내에서 다양한 변형 및 수정이 가능함은 당업자에게 있어서 명백한 것이며, 이러한 변형 및 수정이 첨부된 특허청구범위에 속함은 당연한 것이다.On the other hand, the present invention has been described in detail only with respect to the specific examples described above it will be apparent to those skilled in the art that various modifications and variations are possible within the technical scope of the present invention, it is natural that such variations and modifications belong to the appended claims. .

Claims (6)

컨트롤러에 각각 측정된 휠속도가 입력되는 휠속도입력단계;
컨트롤러가 미리 확보된 휠속도데이터를 이용하여 각각의 휠속도평균값에 대한 통계적 신뢰구간을 설정하는 신뢰구간설정단계; 및
컨트롤러는 상기 휠속도가 상기 신뢰구간을 이탈하는 경우, 신뢰구간을 이탈한 휠속도를 제외한 나머지 휠속도를 기준으로 차속을 추정하여 후륜의 조향 작동을 제어하는 제1페일세이프단계;를 포함하는 후륜 조향 제어방법.
A wheel speed input step of inputting measured wheel speeds to the controller, respectively;
A confidence interval setting step of setting, by the controller, a statistical confidence interval for each wheel speed average value using previously secured wheel speed data; And
The controller includes a first fail-safe step of controlling a steering operation of the rear wheel by estimating the vehicle speed based on the remaining wheel speed except for the wheel speed that leaves the confidence interval when the wheel speed deviates from the confidence interval. Steering Control Method.
청구항 1에 있어서,
상기 신뢰구간설정단계 이 후에,
각각의 휠속도 모두가 신뢰구간을 이탈하는지 판단하는 휠속도판단단계;를 더 포함하는 것을 특징으로 하는 후륜 조향 제어방법.
The method according to claim 1,
After the confidence interval setting step,
And a wheel speed determination step of determining whether each wheel speed deviates from the confidence interval.
청구항 1에 있어서,
상기 휠속도판단단계의 판단 결과,
각각의 휠속도 모두가 신뢰구간을 이탈하는 경우, 전체 휠속도평균값과 소정값 이상 차이가 발생하는 휠속도를 제외한 나머지 휠속도를 기준으로 차속을 추정하여 후륜의 조향 작동을 제어하는 제2페일세이프단계;를 더 포함하는 것을 특징으로 하는 후륜 조향 제어방법.
The method according to claim 1,
The determination result of the wheel speed determination step,
Second fail-safe to control steering operation of rear wheels by estimating the vehicle speed based on the remaining wheel speed except the wheel speed where the difference between the total wheel speed average value and a predetermined value is exceeded when both wheel speeds deviate from the confidence interval. The rear wheel steering control method further comprising.
청구항 3에 있어서,
상기 제2페일세이프단계는,
차량의 종가속도를 판단하고;
상기 종가속도가 0 이상인 경우, 전체 휠속도평균값보다 큰 휠속도를 제외한 나머지 휠속도를 기준으로 차속을 추정하며;
상기 종가속도가 0 미만인 경우, 전체 휠속도평균값보다 작은 휠속도를 제외한 나머지 휠속도를 기준으로 차속을 추정하는 것을 특징으로 하는 후륜 조향 제어방법.
The method according to claim 3,
The second fail safe step,
Determine a longitudinal acceleration of the vehicle;
When the longitudinal acceleration is greater than or equal to zero, estimating a vehicle speed based on the remaining wheel speed except for a wheel speed larger than an average of the total wheel speed;
And when the longitudinal acceleration is less than zero, estimating the vehicle speed based on the remaining wheel speed except for the wheel speed smaller than the average wheel speed average value.
청구항 1에 있어서,
상기 휠속도가 신뢰구간을 이탈한 경우, 휠속도가 이탈 직전 휠속도 대비하여 기준율 이상이고, 일정시간 이상 지속시, 후륜을 중립으로 이동하여 후륜 조향을 실시하지 않도록 제어하는 제3페일세이프단계;를 더 포함하는 것을 특징으로 하는 후륜 조향 제어방법.
The method according to claim 1,
A third fail-safe step of controlling the rear wheels to be neutral and not to perform rear wheel steering when the wheel speed is out of the confidence interval and the wheel speed is higher than the reference ratio in comparison to the wheel speed immediately before the departure, and for a predetermined time; Rear wheel steering control method characterized in that it further comprises.
청구항 1에 있어서,
상기 휠속도가 상기 신뢰구간을 이탈한 후에, 각각의 휠속도 중 최고 휠속도와 최저 휠속도 차이가 설정속도 이하인 경우, 전체 휠속도를 기준으로 차속을 추정하여 후륜의 조향 작동을 제어하는 정상제어단계;를 더 포함하는 것을 특징으로 하는 후륜 조향 제어방법.
The method according to claim 1,
After the wheel speed deviates from the confidence interval, when the difference between the highest wheel speed and the lowest wheel speed among the respective wheel speeds is less than or equal to the set speed, the normal control of estimating the vehicle speed based on the total wheel speed to control the steering operation of the rear wheels. The rear wheel steering control method further comprising.
KR1020180068850A 2018-06-15 2018-06-15 Steering control method for rear wheel steering KR102575395B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR1020180068850A KR102575395B1 (en) 2018-06-15 2018-06-15 Steering control method for rear wheel steering

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
KR1020180068850A KR102575395B1 (en) 2018-06-15 2018-06-15 Steering control method for rear wheel steering

Publications (2)

Publication Number Publication Date
KR20190141967A true KR20190141967A (en) 2019-12-26
KR102575395B1 KR102575395B1 (en) 2023-09-07

Family

ID=69103526

Family Applications (1)

Application Number Title Priority Date Filing Date
KR1020180068850A KR102575395B1 (en) 2018-06-15 2018-06-15 Steering control method for rear wheel steering

Country Status (1)

Country Link
KR (1) KR102575395B1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11993265B2 (en) * 2020-08-20 2024-05-28 Subaru Corporation Control apparatus

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5278625A (en) * 1975-10-16 1977-07-02 Vickers Ltd Method and apparatus for forming antifriction layer
KR20080019786A (en) 2006-08-29 2008-03-05 현대자동차주식회사 A rollover method apparatus for a 4ws vehicle
KR20090078250A (en) * 2008-01-14 2009-07-17 콘티넨탈 오토모티브 시스템 주식회사 Apparatus and method for diagoning vehicle speed sensor of vehicle
KR20130000993A (en) * 2011-06-24 2013-01-03 주식회사 유라코퍼레이션 Driving system for vehicle
KR20160026492A (en) * 2014-09-01 2016-03-09 목포대학교산학협력단 Anomaly detection method using confidence interval estimation based on time series analysis
KR20170129464A (en) * 2016-05-17 2017-11-27 현대자동차주식회사 System and Method for Detecting Speed of Vehicle

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5278625A (en) * 1975-10-16 1977-07-02 Vickers Ltd Method and apparatus for forming antifriction layer
KR20080019786A (en) 2006-08-29 2008-03-05 현대자동차주식회사 A rollover method apparatus for a 4ws vehicle
KR20090078250A (en) * 2008-01-14 2009-07-17 콘티넨탈 오토모티브 시스템 주식회사 Apparatus and method for diagoning vehicle speed sensor of vehicle
KR20130000993A (en) * 2011-06-24 2013-01-03 주식회사 유라코퍼레이션 Driving system for vehicle
KR20160026492A (en) * 2014-09-01 2016-03-09 목포대학교산학협력단 Anomaly detection method using confidence interval estimation based on time series analysis
KR20170129464A (en) * 2016-05-17 2017-11-27 현대자동차주식회사 System and Method for Detecting Speed of Vehicle

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11993265B2 (en) * 2020-08-20 2024-05-28 Subaru Corporation Control apparatus

Also Published As

Publication number Publication date
KR102575395B1 (en) 2023-09-07

Similar Documents

Publication Publication Date Title
CN107628036B (en) Detection and reconstruction of sensor faults
US11731611B2 (en) Vehicle stability control method and device
CN107300395B (en) Pitch rate sensor fault detection and reconstruction
KR102478124B1 (en) Control system of drive wheel of vehicle and control method of using the same
US11383723B2 (en) Vehicle control device
CN107914771B (en) Steering system steering wheel angle determination
CN104903129A (en) System and method for monitoring estimated wheel speed of vehicle using transmission output shaft sensor
CN107298094B (en) Detection and reconstruction of roll rate sensor failures
US20070078576A1 (en) System and method for fuzzy-logic based fault diagnosis
JP2002536233A (en) Sensor monitoring method and apparatus, especially for vehicular ESP systems
KR20190141967A (en) Steering control method for rear wheel steering
KR102585752B1 (en) Control method of rear wheel steering system
KR102654845B1 (en) Apparatus for estimating friction coefficient of road surface
JP2658600B2 (en) Vehicle control device
KR101514132B1 (en) Four-wheel drive vehicle's steering angle estimation method
JP5339918B2 (en) Method and apparatus for controlling rotation angle of rear wheel of automobile and automobile
JP2021088349A (en) Wheel diameter correction device, correction system and program
JP3255108B2 (en) Failure determination device for yaw rate sensor
KR102634451B1 (en) Steering control method for rear wheel steering
KR101639815B1 (en) Detecting method of bank-road
US20170066422A1 (en) Method For Setting A Slip Threshold and Vehicle Movement Dynamics Control Device
US6640167B1 (en) Method of detecting and managing sensor fault for safety-critical road-wheel position in vehicle steer-by-wire systems
CN112319493A (en) Vehicle speed determination method and device, storage medium and vehicle
CN117719520A (en) Unit and method for determining a reference vehicle speed of a vehicle
GB2553121A (en) Watchdog controller

Legal Events

Date Code Title Description
A201 Request for examination
E902 Notification of reason for refusal
E701 Decision to grant or registration of patent right