JP2011183966A - Road surface friction coefficient presumption device - Google Patents

Road surface friction coefficient presumption device Download PDF

Info

Publication number
JP2011183966A
JP2011183966A JP2010052365A JP2010052365A JP2011183966A JP 2011183966 A JP2011183966 A JP 2011183966A JP 2010052365 A JP2010052365 A JP 2010052365A JP 2010052365 A JP2010052365 A JP 2010052365A JP 2011183966 A JP2011183966 A JP 2011183966A
Authority
JP
Japan
Prior art keywords
tire
friction coefficient
road surface
measuring means
automobile
Prior art date
Legal status (The legal status 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 status listed.)
Granted
Application number
JP2010052365A
Other languages
Japanese (ja)
Other versions
JP5686363B2 (en
Inventor
Koichi Oka
宏一 岡
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Kochi University of Technology
Original Assignee
Kochi University of Technology
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 Kochi University of Technology filed Critical Kochi University of Technology
Priority to JP2010052365A priority Critical patent/JP5686363B2/en
Publication of JP2011183966A publication Critical patent/JP2011183966A/en
Application granted granted Critical
Publication of JP5686363B2 publication Critical patent/JP5686363B2/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Landscapes

  • Control Of Driving Devices And Active Controlling Of Vehicle (AREA)
  • Regulating Braking Force (AREA)

Abstract

<P>PROBLEM TO BE SOLVED: To provide a road surface friction coefficient presumption device capable of presuming friction coefficient of a tire and a road surface at turning of an automobile at a real time without using simulation, capable of making it to a simple device without requiring a large sized exclusive vehicle and not perform driving not intended by a driver during traveling. <P>SOLUTION: The road surface friction coefficient presumption device includes a rotational speed measurement means for measuring the rotational speed of left and right tires of the automobile; an advancement direction measurement means for measuring an advancement direction of the automobile; an actual steering angle measurement means for measuring an actual steering angle of the tire; a direction measurement means for measuring a direction of the automobile; and a presumption means for presuming the friction coefficient at turning of the tire and the road surface based on the respective measurement value of the rotational speed measurement means, the advancement direction measurement means, the actual steering angle measurement means and the direction measurement means. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

本発明は路面摩擦係数推定装置に関し、より詳しくは自動車の旋回時におけるタイヤと路面との摩擦係数をリアルタイムで推定する装置に関する。   The present invention relates to a road surface friction coefficient estimating apparatus, and more particularly to an apparatus for estimating a friction coefficient between a tire and a road surface in real time when an automobile turns.

冬季には降雪や路面の凍結により車両のスリップ事故が発生し易くなる。
スリップ事故が発生する際には、タイヤと路面との摩擦係数が低下していると考えられる。
そのため、この摩擦係数(路面摩擦係数)をリアルタイムで検知することができれば、運転者への警告やアクティブ操舵、検知した情報の共有による道路情報網の整備等に利用することができ、スリップ事故の発生を抑制することが可能となる。
In winter, slipping of the vehicle is more likely to occur due to snowfall or freezing of the road surface.
When a slip accident occurs, it is considered that the coefficient of friction between the tire and the road surface is reduced.
Therefore, if this friction coefficient (road surface friction coefficient) can be detected in real time, it can be used for warning and active steering to the driver, maintenance of the road information network by sharing the detected information, etc. Occurrence can be suppressed.

スリップ事故は様々な状況で発生するが、例えば車両の旋回時において生じ易いことが知られている。
従来、車両旋回時における摩擦係数を推定する方法が種々提案されているが、提案されている方法の多くは、正確なシミュレーションモデルが必要であったり、大型の専用車両が必要であったりするため、簡便な装置とはなり得ない。
Although a slip accident occurs in various situations, it is known that, for example, it easily occurs when the vehicle turns.
Conventionally, various methods for estimating the friction coefficient when turning a vehicle have been proposed, but many of the proposed methods require an accurate simulation model or a large dedicated vehicle. It cannot be a simple device.

一方、下記特許文献1には、車両が直進中であるか旋回時であるかを判断した後、車輪を積極的にスリップさせることにより摩擦係数を検出する装置が開示されている。
しかし、このような装置では、走行中に運転者の意図しない駆動が生じることにより、運転者が違和感を覚えたり危険性が増したりする虞がある。
On the other hand, Patent Document 1 below discloses an apparatus that detects a friction coefficient by positively slipping a wheel after determining whether the vehicle is traveling straight or turning.
However, in such a device, there is a risk that the driver may feel uncomfortable or increase the risk due to driving that is not intended by the driver during traveling.

特開2006−15926号公報JP 2006-15926 A

本発明は、上記したような従来技術の問題点を解決すべくなされたものであって、自動車の旋回時におけるタイヤと路面との摩擦係数を、シミュレーションを用いずにリアルタイムで推定することができるとともに、大型の専用車両が必要とせずに簡便な装置とすることが可能であり、更に走行中に運転者の意図しない駆動が行われることがない路面摩擦係数推定装置を提供するものである。   The present invention has been made to solve the above-described problems of the prior art, and can estimate the coefficient of friction between the tire and the road surface when the vehicle is turning without using a simulation in real time. In addition, the present invention provides a road surface friction coefficient estimating device that can be a simple device without requiring a large dedicated vehicle and that is not driven by the driver during traveling.

請求項1に係る発明は、自動車の左右のタイヤの回転数を測定する回転数測定手段と、自動車の進行方向を測定する進行方向測定手段と、前記タイヤの実舵角を測定する実舵角測定手段と、自動車の向きを測定する方角測定手段と、前記回転数測定手段、進行方向測定手段、実舵角測定手段、方角測定手段の各測定値に基づいてタイヤと路面の旋回時における摩擦係数を推定する推定手段とを備えていることを特徴とする路面摩擦係数推定装置に関する。   The invention according to claim 1 is a rotational speed measuring means for measuring the rotational speed of the left and right tires of the automobile, a traveling direction measuring means for measuring the traveling direction of the automobile, and an actual steering angle for measuring the actual steering angle of the tire. Friction at the time of turning between the tire and the road surface based on the measured values, the direction measuring means for measuring the direction of the automobile, the rotational speed measuring means, the traveling direction measuring means, the actual rudder angle measuring means, and the direction measuring means The present invention relates to a road surface friction coefficient estimating apparatus including an estimating means for estimating a coefficient.

請求項2に係る発明は、前記推定手段が、旋回時にタイヤに加わる遠心力からタイヤにかかる横力を算出する第一の横力算出式と、旋回時のタイヤの変形からタイヤにかかる横力を求める第二の横力算出式と、旋回時にタイヤが滑りだす滑り開始位置を求める滑り開始位置算出式とに基づいてタイヤと路面の旋回時における摩擦係数を算出することを特徴とする請求項1記載の路面摩擦係数推定装置に関する。   The invention according to claim 2 is characterized in that the estimating means calculates a lateral force applied to the tire from a centrifugal force applied to the tire during turning, and a lateral force applied to the tire from deformation of the tire during turning. The friction coefficient at the time of turning between the tire and the road surface is calculated on the basis of a second lateral force calculating expression for obtaining the tire and a slip starting position calculating expression for obtaining the slip starting position at which the tire starts to slide during turning. 1. The road surface friction coefficient estimating apparatus according to 1.

請求項3に係る発明は、前記第一の横力算出式が、前記回転数測定手段により測定された旋回時の左右のタイヤの回転数の差と、左右のタイヤ間の距離と、タイヤに加わる重量に基づいて、タイヤに加わる遠心力をタイヤにかかる横力として算出する式であることを特徴とする請求項2記載の路面摩擦係数推定装置に関する。   According to a third aspect of the present invention, the first lateral force calculation formula includes a difference between the rotational speeds of the left and right tires during turning measured by the rotational speed measuring means, a distance between the left and right tires, 3. The road surface friction coefficient estimating apparatus according to claim 2, wherein a centrifugal force applied to the tire is calculated as a lateral force applied to the tire based on the applied weight.

請求項4に係る発明は、前記第二の横力算出式が、タイヤのスリップ角と、タイヤの横弾性係数と、タイヤに加わる荷重と、タイヤの接地長と、前記滑り開始位置算出式により求められる滑り開始位置に基づいて、タイヤにかかる横力を算出する式であることを特徴とする請求項2又は3記載の路面摩擦係数推定装置に関する。   In the invention according to claim 4, the second lateral force calculation formula is based on a tire slip angle, a tire lateral elastic modulus, a load applied to the tire, a tire contact length, and the slip start position calculation formula. 4. The road surface friction coefficient estimating apparatus according to claim 2, wherein the road surface friction coefficient estimating apparatus is a formula for calculating a lateral force applied to a tire based on a required slip start position.

請求項5に係る発明は、前記タイヤのスリップ角が、前記進行方向測定手段により測定された進行方向と、前記実舵角測定手段により測定された実舵角と、前記方角測定手段により測定された自動車の向きに基づいて算出されることを特徴とする請求項4記載の路面摩擦係数推定装置に関する。   In the invention according to claim 5, the slip angle of the tire is measured by the traveling direction measured by the traveling direction measuring unit, the actual steering angle measured by the actual steering angle measuring unit, and the direction measuring unit. 5. The road surface friction coefficient estimating device according to claim 4, wherein the road surface friction coefficient estimating device is calculated based on the direction of the automobile.

請求項6に係る発明は、前記滑り開始位置算出式が、前記スリップ角と、前記滑り開始位置と、前記タイヤの接地長と、前記タイヤに加わる重量と、前記摩擦係数に基づいて、滑り開始位置を算出する式であることを特徴とする請求項4又は5記載の路面摩擦係数推定装置に関する。   According to a sixth aspect of the present invention, the slip start position calculation formula is based on the slip angle, the slip start position, the contact length of the tire, the weight applied to the tire, and the friction coefficient. 6. The road surface friction coefficient estimating apparatus according to claim 4, wherein the road surface friction coefficient estimating apparatus is an expression for calculating a position.

請求項7に係る発明は、前記回転数測定手段が、アンチロックブレーキシステムにおける回転数モニタリング手段であることを特徴とする請求項1乃至6いずれかに記載の路面摩擦係数推定装置に関する。   The invention according to claim 7 relates to the road surface friction coefficient estimating device according to any one of claims 1 to 6, wherein the rotational speed measuring means is rotational speed monitoring means in an antilock brake system.

請求項8に係る発明は、前記進行方向測定手段が、自動車に搭載されたGPSであることを特徴とする請求項1乃至7いずれかに記載の路面摩擦係数推定装置に関する。   The invention according to claim 8 relates to the road surface friction coefficient estimating device according to any one of claims 1 to 7, wherein the traveling direction measuring means is a GPS mounted on an automobile.

請求項9に係る発明は、前記実舵角測定手段が、タイヤの車軸に取り付けられた直動型変位センサであることを特徴とする請求項1乃至8いずれかに記載の路面摩擦係数推定装置に関する。   The invention according to claim 9 is the road surface friction coefficient estimating device according to any one of claims 1 to 8, wherein the actual rudder angle measuring means is a linear motion type displacement sensor attached to a tire axle. About.

請求項10に係る発明は、前記方角測定手段が、自動車に搭載された複数のアンテナを備えたGPSコンパスであることを特徴とする請求項1乃至9いずれかに記載の路面摩擦係数推定装置に関する。   The invention according to claim 10 relates to the road surface friction coefficient estimating device according to any one of claims 1 to 9, wherein the direction measuring means is a GPS compass having a plurality of antennas mounted on an automobile. .

本発明に係る路面摩擦係数推定装置は、自動車の左右のタイヤの回転数を測定する回転数測定手段と、自動車の進行方向を測定する進行方向測定手段と、前記タイヤの実舵角を測定する実舵角測定手段と、自動車の向きを測定する方角測定手段と、前記各手段の測定値に基づいてタイヤと路面の旋回時における摩擦係数を推定する推定手段とを備えていることから、自動車の旋回時におけるタイヤと路面との摩擦係数を、シミュレーションを用いずに解析的手法によりリアルタイムで推定することができる。また、大型の専用車両を必要とせずに簡便な装置とすることが可能であるから、様々な自動車に搭載することができ、実用性、汎用性に優れている。更に、走行中に運転者の意図しない駆動がなされることがないため、運転者が違和感を覚える虞がなく安全である。   A road surface friction coefficient estimating apparatus according to the present invention measures a rotational speed measuring means for measuring the rotational speed of left and right tires of an automobile, a traveling direction measuring means for measuring a traveling direction of the automobile, and an actual steering angle of the tire. The vehicle includes an actual rudder angle measuring means, a direction measuring means for measuring the direction of the automobile, and an estimating means for estimating a friction coefficient during turning of the tire and the road surface based on the measured values of the respective means. It is possible to estimate the friction coefficient between the tire and the road surface at the time of turning in real time by an analytical method without using simulation. Moreover, since it is possible to make a simple device without requiring a large dedicated vehicle, it can be installed in various automobiles, and is excellent in practicality and versatility. Furthermore, since driving that is not intended by the driver is not performed during traveling, the driver does not have a possibility of feeling uncomfortable and is safe.

本発明に係る路面摩擦係数推定装置の構成を示すブロック図である。It is a block diagram which shows the structure of the road surface friction coefficient estimation apparatus which concerns on this invention. 自動車が旋回している時にタイヤに生じる力を示す説明図である。It is explanatory drawing which shows the force which arises on a tire when the motor vehicle is turning. 左右のタイヤの移動距離と旋回半径を近似した説明図である。It is explanatory drawing which approximated the moving distance and turning radius of a right-and-left tire. 上図はタイヤの接地長とタイヤにかかる重量(荷重)の関係を示すグラフであり、下図はタイヤの接地長とタイヤの横方向の変形量(ゆがみ量)の関係を示すグラフである。The upper diagram is a graph showing the relationship between the tire contact length and the weight (load) applied to the tire, and the lower diagram is the graph showing the relationship between the tire contact length and the lateral deformation amount (distortion amount) of the tire.

以下、本発明に係る路面摩擦係数推定装置の好適な実施形態について、図面を参照しながら説明する。
図1は本発明に係る路面摩擦係数推定装置の構成を示すブロック図である。
本発明に係る路面摩擦係数推定装置は、自動車の左右のタイヤの回転数を測定する回転数測定手段(1)と、自動車の進行方向を測定する進行方向測定手段(2)と、タイヤの実舵角を測定する実舵角測定手段(3)と、自動車の向きを測定する方角測定手段(4)と、前記各手段(1〜4)の測定値に基づいてタイヤと路面の旋回時における摩擦係数を推定する推定手段(5)とを備えている。
Hereinafter, a preferred embodiment of a road surface friction coefficient estimating apparatus according to the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram showing a configuration of a road surface friction coefficient estimating apparatus according to the present invention.
A road surface friction coefficient estimating apparatus according to the present invention includes a rotational speed measuring means (1) for measuring rotational speeds of left and right tires of an automobile, a traveling direction measuring means (2) for measuring the traveling direction of the automobile, and tire actuality. The actual steering angle measuring means (3) for measuring the steering angle, the direction measuring means (4) for measuring the direction of the automobile, and the tire and the road surface when turning based on the measured values of the means (1 to 4). And an estimation means (5) for estimating a friction coefficient.

回転数測定手段(1)としては、アンチロックブレーキシステム(Antilock Brake System、以下ABSと略)における回転数モニタリング手段が好適に使用される。
ABSは、周知の如く、急ブレーキや低摩擦路面でのブレーキ操作においてタイヤがロックして滑るのを防止する装置である。ABSはタイヤの回転数をモニタしており、ブレーキを踏んだ際にタイヤがロックされたことを検知すると、制動力を弱めてロック解除し、再び制動力を強めてブレーキをかける。
本発明においては、自動車に備えられたABSが有する回転数モニタリング手段を回転数測定手段(1)として使用する。以下、本明細書において、ABSの回転数をモニタする信号をABS信号と称する。
回転数測定手段(1)により測定された旋回時の左右のタイヤの回転数の差が、後述するタイヤに加わる遠心力をタイヤにかかる横力として算出する第一の横力算出式において用いられる。
As the rotational speed measuring means (1), rotational speed monitoring means in an antilock brake system (hereinafter referred to as ABS) is preferably used.
As is well known, the ABS is a device that prevents the tire from locking and slipping during a sudden braking or braking operation on a low friction road surface. The ABS monitors the number of rotations of the tire. When the ABS detects that the tire is locked when the brake is depressed, the braking force is weakened to release the lock, and the braking force is increased again to apply the brake.
In the present invention, the rotational speed monitoring means possessed by the ABS provided in the automobile is used as the rotational speed measuring means (1). Hereinafter, in this specification, a signal for monitoring the rotational speed of the ABS is referred to as an ABS signal.
The difference between the rotational speeds of the left and right tires during turning measured by the rotational speed measuring means (1) is used in a first lateral force calculation formula for calculating a centrifugal force applied to the tire, which will be described later, as a lateral force applied to the tire. .

進行方向測定手段(2)としては、自動車に搭載されたGPS(Global Positioning System)が好適に使用される。
GPSは自動車の進行方向を検出することができるため、本発明においてはGPSを進行方向測定手段(2)として使用する。
進行方向測定手段(2)であるGPSにより検出された自動車の進行方向は、後述するタイヤのスリップ角の算出のために用いられる。
As the traveling direction measuring means (2), a GPS (Global Positioning System) mounted on an automobile is preferably used.
Since the GPS can detect the traveling direction of the automobile, the GPS is used as the traveling direction measuring means (2) in the present invention.
The traveling direction of the automobile detected by the GPS that is the traveling direction measuring means (2) is used for calculating the slip angle of the tire, which will be described later.

実舵角測定手段(3)としては、タイヤの車軸に取り付けられた直動型変位センサが好適に使用される。
タイヤの車軸とタイヤの実舵角は線形の関係にあると考えられる。そこで、直動型変位センサをタイヤの車軸に取り付けて車軸の横方向の変位を計測することによりタイヤの実舵角を測定する。
実舵角測定手段(3)である直動型変位センサにより測定された実舵角は、後述するタイヤのスリップ角の算出のために用いられる。
As the actual rudder angle measuring means (3), a direct-acting displacement sensor attached to the tire axle is preferably used.
The tire axle and the actual steering angle of the tire are considered to have a linear relationship. Accordingly, the actual steering angle of the tire is measured by attaching a linear motion type displacement sensor to the tire axle and measuring the lateral displacement of the axle.
The actual rudder angle measured by the linear displacement sensor which is the actual rudder angle measuring means (3) is used for calculating the slip angle of the tire described later.

方角測定手段(4)としては、自動車に搭載された複数のアンテナを備えたGPSコンパスが好適に使用される。
GPSコンパスは、GPS電波を複数のアンテナで受信し、その位相差から方角を測定することができる装置である。
方角測定手段(4)であるGPSコンパスにより測定された自動車の向きは、後述するタイヤのスリップ角の算出のために用いられる。
As the direction measuring means (4), a GPS compass having a plurality of antennas mounted on an automobile is preferably used.
The GPS compass is a device that can receive GPS radio waves with a plurality of antennas and measure the direction from the phase difference.
The direction of the automobile measured by the GPS compass as the direction measuring means (4) is used for calculating the slip angle of the tire, which will be described later.

推定手段(5)は、上述した回転数測定手段(1)、進行方向測定手段(2)、実舵角測定手段(3)、方角測定手段(4)の各測定値に基づいて、タイヤと路面の旋回時における摩擦係数をメモリに予め記憶された所定の計算式を使用して計算するコンピュータである。
所定の計算式は、旋回時にタイヤに加わる遠心力からタイヤにかかる横力を算出する第一の横力算出式と、旋回時のタイヤの変形からタイヤにかかる横力を求める第二の横力算出式と、旋回時にタイヤが滑りだす滑り開始位置を求める滑り開始位置算出式とを含んでいる。これらの計算式については後述する。
The estimation means (5) is based on the measured values of the rotation speed measurement means (1), travel direction measurement means (2), actual steering angle measurement means (3), and direction measurement means (4) described above. It is a computer that calculates a friction coefficient when turning on a road surface using a predetermined calculation formula stored in advance in a memory.
The predetermined calculation formula includes a first lateral force calculation formula for calculating the lateral force applied to the tire from the centrifugal force applied to the tire during turning, and a second lateral force for obtaining the lateral force applied to the tire from deformation of the tire during turning. It includes a calculation formula and a slip start position calculation formula for obtaining a slip start position at which the tire starts to slip when turning. These calculation formulas will be described later.

以下、本発明に係る路面摩擦係数推定装置を用いた路面摩擦係数推定方法について詳述する。
<旋回時に発生するスリップ角と横力>
自動車が旋回している時、タイヤの移動方向とタイヤの向いている方向には差が生じる。その角度の差をスリップ角という。
図2は自動車が旋回している時にタイヤに生じる力を示している。
図2の真上方向が進行方向とすると、進行方向への力はタイヤの回転方向とそれに垂直な力に分解される。タイヤの回転方向に垂直な力は、タイヤに働く遠心力であると考えられる。この遠心力に相当する力として旋回内向きに力が発生している。この力を横力という。
Hereinafter, a road surface friction coefficient estimation method using the road surface friction coefficient estimation apparatus according to the present invention will be described in detail.
<Slip angle and lateral force generated during turning>
When the automobile is turning, there is a difference between the tire moving direction and the tire facing direction. The difference in angle is called the slip angle.
FIG. 2 shows the force generated on the tire when the automobile is turning.
Assuming that the upward direction in FIG. 2 is the traveling direction, the force in the traveling direction is broken down into the rotational direction of the tire and the force perpendicular thereto. The force perpendicular to the tire rotation direction is considered to be centrifugal force acting on the tire. A force is generated inwardly as a force corresponding to the centrifugal force. This force is called lateral force.

タイヤを切ることにより前輪にスリップ角が発生する。この際に発生した横力を進行方向とそれに垂直な力に分解した時に、進行方向と垂直な力がコーナリングフォースである。このコーナリングフォースが自動車の重心周りに働き、モーメントが発生して自動車が回頭を始める。自動車が回頭することにより、自動車の向きと同方向に固定された後輪にもスリップ角が発生する。その際、後輪にもコーナリングフォースが発生する。この前後のコーナリングフォースによって発生するモーメントの差により自動車は回頭する。尚、このモーメントが釣り合った際に定常旋回となる。   When the tire is cut, a slip angle is generated on the front wheel. When the lateral force generated at this time is broken down into a traveling direction and a force perpendicular thereto, the force perpendicular to the traveling direction is the cornering force. This cornering force works around the center of gravity of the car, a moment is generated, and the car begins to turn. As the automobile turns, a slip angle is also generated in the rear wheels fixed in the same direction as the automobile. At that time, a cornering force is also generated on the rear wheel. The car turns due to the difference in moment generated by the front and rear cornering forces. In addition, when this moment balances, it becomes steady turning.

<遠心力から求める横力>
回転数測定手段(1)は、ABS信号により左右のタイヤの回転数を検出する。
旋回時は左右のタイヤで回転数に差が生じる。そのため、図3に示すように、左右のタイヤの移動距離と旋回半径が近似できると考えることにより、左右のタイヤの間隔(既知)より各タイヤの旋回半径を求めることができる。
従って、旋回時にタイヤに加わる遠心力は、タイヤにかかる横力として下式(1)(第一の横力算出式)により求めることができる。
<Side force determined from centrifugal force>
The rotational speed measuring means (1) detects the rotational speeds of the left and right tires from the ABS signal.
When turning, there is a difference in the rotational speed between the left and right tires. Therefore, as shown in FIG. 3, by considering that the moving distance and turning radius of the left and right tires can be approximated, the turning radius of each tire can be obtained from the interval (known) of the left and right tires.
Therefore, the centrifugal force applied to the tire at the time of turning can be obtained by the following formula (1) (first lateral force calculation formula) as a lateral force applied to the tire.

横力=mv/R ・・・(1)
m:タイヤにかかる重量、v:速度、R:旋回半径
Lateral force = mv 2 / R (1)
m: weight applied to tire, v: speed, R: turning radius

<タイヤの変形から求める横力>
タイヤにかかる重量mは、図4の上図に示すようにタイヤの接地長さlに対して放物線状にかかるとすると、放物線の式は下式(2)のように仮定できる。

Figure 2011183966

Figure 2011183966

a,b:定数 <Side force determined from tire deformation>
As shown in the upper diagram of FIG. 4, assuming that the weight m applied to the tire is parabolic with respect to the contact length l of the tire, the parabolic equation can be assumed as the following equation (2).

Figure 2011183966

Figure 2011183966

a, b: constant

放物線の式(2)の全区間を積分した値は、タイヤにかかる重量より下式(3)のようになる。

Figure 2011183966

Figure 2011183966
The value obtained by integrating all sections of the parabolic equation (2) is expressed by the following equation (3) from the weight applied to the tire.

Figure 2011183966

Figure 2011183966

進行方向測定手段(2)であるGPSの情報により自動車の進行方向が、方角測定手段(4)であるGPSコンパスにより自動車の向きが、実舵角測定手段(3)である直動型変位センサにより実舵角が夫々求められ、これらからスリップ角が下式(4)の通りに求められる。
β=自動車の向き+実舵角−自動車の進行方向 ・・・(4)
β:スリップ角
Linear motion type displacement sensor in which the traveling direction of the vehicle is determined by GPS information as the traveling direction measuring means (2) and the direction of the vehicle is determined by the GPS compass as the direction measuring means (4). Thus, the actual rudder angle is obtained, and from these, the slip angle is obtained as in the following equation (4).
β = Direction of automobile + Actual steering angle-Direction of movement of automobile (4)
β: slip angle

タイヤは旋回時において図4の下図に示すようにスリップ角βで徐々に横方向に変形していき、ある一点で滑っていると考えられる。
この滑る点(滑り開始位置)は、「タイヤの横弾性係数とその時点までのゆがみの総量の積」と「路面摩擦係数と滑る場所のタイヤにかかっている荷重の積」が釣り合う点であると考えられる。よって、下式(5)が成り立つ。

Figure 2011183966

s:滑り開始位置、μ:路面摩擦係数、G:タイヤの横弾性係数 As shown in the lower diagram of FIG. 4, the tire gradually deforms in the lateral direction at a slip angle β during turning, and is considered to slip at a certain point.
This slipping point (sliding start position) is a point where “the product of the lateral elastic modulus of the tire and the total amount of distortion up to that point” and “the product of the friction coefficient of the road surface and the load applied to the tire in the slipping place” are balanced. it is conceivable that. Therefore, the following formula (5) is established.

Figure 2011183966

s: slip start position, μ: road surface friction coefficient, G: tire transverse elastic coefficient

式(5)をsについて整理すると、下式(6)(滑り開始位置算出式)となる。

Figure 2011183966
When formula (5) is arranged for s, the following formula (6) (slip start position calculation formula) is obtained.

Figure 2011183966

図4の下図の全区間を積分した値が横力となる。
滑り開始位置移行の曲線部分を直線で近似すると、横力は下式(7)(第二の横力算出式)のように求められる。

Figure 2011183966
The value obtained by integrating all the sections in the lower diagram of FIG. 4 is the lateral force.
When the curve portion of the slip start position transition is approximated by a straight line, the lateral force can be obtained by the following equation (7) (second lateral force calculation equation).

Figure 2011183966

推定手段(5)は、式(1)(第一の横力算出式)、式(6)(滑り開始位置算出式)、式(7)(第二の横力算出式)の連立式を解くことにより、旋回時における路面摩擦係数を下式(8)のように求める。

Figure 2011183966
The estimation means (5) is a simultaneous expression of Expression (1) (First lateral force calculation expression), Expression (6) (Slip start position calculation expression), and Expression (7) (Second lateral force calculation expression). By solving, the road surface friction coefficient at the time of turning is obtained as in the following equation (8).

Figure 2011183966

以上より、本発明によれば、シミュレーションを用いずにリアルタイムで路面摩擦係数を求めることができる。
更に、本発明によれば、各タイヤでそれぞれ路面摩擦係数を推定することもできる。
複数輪の兼ね合いは、車体及び積載物の重量分布とそれらのモーメントからタイヤにかかる重量を求めることのみで行うことができる。
As mentioned above, according to this invention, a road surface friction coefficient can be calculated | required in real time, without using a simulation.
Furthermore, according to the present invention, the road surface friction coefficient can be estimated for each tire.
The multiple wheels can be balanced only by obtaining the weight applied to the tire from the weight distribution of the vehicle body and the load and their moments.

本発明に係る装置は、自動車の旋回時におけるタイヤと路面との摩擦係数をリアルタイムで推定することができるため、車両に搭載することにより、運転者への警告やアクティブ操舵に利用することができる。また、多くの自動車が検知した情報を共有化することにより道路情報網の整備等に利用することもできる。   Since the apparatus according to the present invention can estimate the friction coefficient between the tire and the road surface in a real time when the vehicle turns, it can be used for warning to the driver and active steering by being mounted on the vehicle. . In addition, by sharing information detected by many automobiles, it can be used for maintenance of a road information network.

1 回転数測定手段
2 進行方向測定手段
3 実舵角測定手段
4 方角測定手段
5 推定手段
DESCRIPTION OF SYMBOLS 1 Rotational speed measuring means 2 Traveling direction measuring means 3 Actual steering angle measuring means 4 Direction measuring means 5 Estimating means

Claims (10)

自動車の左右のタイヤの回転数を測定する回転数測定手段と、
自動車の進行方向を測定する進行方向測定手段と、
前記タイヤの実舵角を測定する実舵角測定手段と、
自動車の向きを測定する方角測定手段と、
前記回転数測定手段、進行方向測定手段、実舵角測定手段、方角測定手段の各測定値に基づいてタイヤと路面の旋回時における摩擦係数を推定する推定手段と
を備えていることを特徴とする路面摩擦係数推定装置。
Rotational speed measuring means for measuring the rotational speed of the left and right tires of the automobile,
A traveling direction measuring means for measuring the traveling direction of the automobile;
An actual rudder angle measuring means for measuring an actual rudder angle of the tire;
A direction measuring means for measuring the direction of the automobile,
And an estimation means for estimating a friction coefficient during turning of the tire and the road surface based on the measured values of the rotational speed measurement means, the traveling direction measurement means, the actual rudder angle measurement means, and the direction measurement means. Road friction coefficient estimation device.
前記推定手段が、
旋回時にタイヤに加わる遠心力からタイヤにかかる横力を算出する第一の横力算出式と、
旋回時のタイヤの変形からタイヤにかかる横力を求める第二の横力算出式と、
旋回時にタイヤが滑りだす滑り開始位置を求める滑り開始位置算出式と、
に基づいてタイヤと路面の旋回時における摩擦係数を算出することを特徴とする請求項1記載の路面摩擦係数推定装置。
The estimating means is
A first lateral force calculation formula for calculating the lateral force applied to the tire from the centrifugal force applied to the tire during turning;
A second lateral force calculation formula for obtaining the lateral force applied to the tire from the deformation of the tire during turning;
A slip start position calculation formula for obtaining a slip start position at which the tire starts to slip when turning,
The road surface friction coefficient estimating device according to claim 1, wherein a friction coefficient at the time of turning between the tire and the road surface is calculated based on the equation (1).
前記第一の横力算出式が、
前記回転数測定手段により測定された旋回時の左右のタイヤの回転数の差と、左右のタイヤ間の距離と、タイヤに加わる重量に基づいて、タイヤに加わる遠心力をタイヤにかかる横力として算出する式であることを特徴とする請求項2記載の路面摩擦係数推定装置。
The first lateral force calculation formula is
The centrifugal force applied to the tire is defined as the lateral force applied to the tire based on the difference between the rotational speeds of the left and right tires when turning, the distance between the left and right tires, and the weight applied to the tire, as measured by the rotational speed measuring means. 3. The road surface friction coefficient estimating device according to claim 2, wherein the road surface friction coefficient estimating device is an equation to be calculated.
前記第二の横力算出式が、
タイヤのスリップ角と、タイヤの横弾性係数と、タイヤに加わる荷重と、タイヤの接地長と、前記滑り開始位置算出式により求められる滑り開始位置に基づいて、タイヤにかかる横力を算出する式であることを特徴とする請求項2又は3記載の路面摩擦係数推定装置。
The second lateral force calculation formula is
Formula for calculating the lateral force applied to the tire based on the slip angle of the tire, the tire's lateral elastic modulus, the load applied to the tire, the contact length of the tire, and the slip start position obtained from the slip start position calculation formula The road surface friction coefficient estimating device according to claim 2 or 3, wherein:
前記タイヤのスリップ角が、
前記進行方向測定手段により測定された進行方向と、前記実舵角測定手段により測定された実舵角と、前記方角測定手段により測定された自動車の向きに基づいて算出されることを特徴とする請求項4記載の路面摩擦係数推定装置。
The slip angle of the tire is
It is calculated based on the traveling direction measured by the traveling direction measuring means, the actual steering angle measured by the actual steering angle measuring means, and the direction of the automobile measured by the direction measuring means. The road surface friction coefficient estimating apparatus according to claim 4.
前記滑り開始位置算出式が、
前記スリップ角と、前記滑り開始位置と、前記タイヤの接地長と、前記タイヤに加わる重量と、前記摩擦係数に基づいて、滑り開始位置を算出する式であることを特徴とする請求項4又は5記載の路面摩擦係数推定装置。
The slip start position calculation formula is
5. The equation for calculating a slip start position based on the slip angle, the slip start position, a contact length of the tire, a weight applied to the tire, and the friction coefficient. 5. The road surface friction coefficient estimating device according to 5.
前記回転数測定手段が、アンチロックブレーキシステムにおける回転数モニタリング手段であることを特徴とする請求項1乃至6いずれかに記載の路面摩擦係数推定装置。   The road surface friction coefficient estimating device according to any one of claims 1 to 6, wherein the rotational speed measuring means is rotational speed monitoring means in an anti-lock brake system. 前記進行方向測定手段が、自動車に搭載されたGPSであることを特徴とする請求項1乃至7いずれかに記載の路面摩擦係数推定装置。   The road friction coefficient estimating device according to any one of claims 1 to 7, wherein the traveling direction measuring means is a GPS mounted on an automobile. 前記実舵角測定手段が、タイヤの車軸に取り付けられた直動型変位センサであることを特徴とする請求項1乃至8いずれかに記載の路面摩擦係数推定装置。   The road surface friction coefficient estimating device according to any one of claims 1 to 8, wherein the actual rudder angle measuring means is a linear displacement sensor attached to an axle of a tire. 前記方角測定手段が、自動車に搭載された複数のアンテナを備えたGPSコンパスであることを特徴とする請求項1乃至9いずれかに記載の路面摩擦係数推定装置。   The road surface friction coefficient estimating apparatus according to any one of claims 1 to 9, wherein the direction measuring means is a GPS compass having a plurality of antennas mounted on an automobile.
JP2010052365A 2010-03-09 2010-03-09 Road friction coefficient estimation device Expired - Fee Related JP5686363B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2010052365A JP5686363B2 (en) 2010-03-09 2010-03-09 Road friction coefficient estimation device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2010052365A JP5686363B2 (en) 2010-03-09 2010-03-09 Road friction coefficient estimation device

Publications (2)

Publication Number Publication Date
JP2011183966A true JP2011183966A (en) 2011-09-22
JP5686363B2 JP5686363B2 (en) 2015-03-18

Family

ID=44790762

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2010052365A Expired - Fee Related JP5686363B2 (en) 2010-03-09 2010-03-09 Road friction coefficient estimation device

Country Status (1)

Country Link
JP (1) JP5686363B2 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2015190769A1 (en) * 2014-06-11 2015-12-17 서울대학교 산학협력단 Vehicle active safety system

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11198787A (en) * 1998-01-19 1999-07-27 Nippon Abs Ltd Turn sensing method in antiskid control
JP2006044316A (en) * 2004-07-30 2006-02-16 Nissan Motor Co Ltd Vehicle state quantity sensing device

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11198787A (en) * 1998-01-19 1999-07-27 Nippon Abs Ltd Turn sensing method in antiskid control
JP2006044316A (en) * 2004-07-30 2006-02-16 Nissan Motor Co Ltd Vehicle state quantity sensing device

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2015190769A1 (en) * 2014-06-11 2015-12-17 서울대학교 산학협력단 Vehicle active safety system

Also Published As

Publication number Publication date
JP5686363B2 (en) 2015-03-18

Similar Documents

Publication Publication Date Title
CN110382326B (en) Method and device for estimating road surface friction coefficient of tire under high-speed normal driving condition
CN108791298B (en) Method and system for calculating road friction estimate
EP2995520B1 (en) Tire grounded state estimation method
EP2955078B1 (en) Tire classfication
JP6122916B2 (en) System and method for determining tire wear
CN105829185B (en) Potential adhesive force is estimated by assessment rolling radius
EP3309024B1 (en) Method and system for determining friction between the ground and a tire of a vehicle
EP3807105B1 (en) Tread wear monitoring system and method
EP2295301A1 (en) Road surface friction coefficient estimating device and road surface friction coefficient estimating method
KR102030714B1 (en) Control of regenerative braking in an electric or hybrid vehicle
WO2008112667A1 (en) Methods and systems for friction detection and slippage control
WO2007116123A1 (en) Method for collecting information on road surface slipperiness
JP2014532170A (en) Method for estimating rolling resistance of vehicle wheel
EP3501924B1 (en) Wheel load estimation device
JP2008265545A (en) Center of gravity position estimating device of vehicle and center of gravity position/yaw inertia moment estimating device
JP2006131136A (en) Vehicular signal processing unit
KR101213620B1 (en) Electronic stability control apparatus by using wheel lateral acceleration
JP5686363B2 (en) Road friction coefficient estimation device
JP4636991B2 (en) Road surface state estimation device and method, and road surface state estimation program
JP4028842B2 (en) Tire pressure drop detection method and apparatus, and tire decompression determination program
JP2006256469A (en) Method of estimating vehicle body slip angle, and slip angle of four wheels
JP2007106169A (en) Road surface condition presuming device and method, and program for presuming road surface condition
JP4536089B2 (en) Tire pressure drop detection method and apparatus, and tire decompression determination program

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20130308

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20131009

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20131010

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20131206

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20140528

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20140728

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20141222

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20150114

R150 Certificate of patent or registration of utility model

Ref document number: 5686363

Country of ref document: JP

Free format text: JAPANESE INTERMEDIATE CODE: R150

S111 Request for change of ownership or part of ownership

Free format text: JAPANESE INTERMEDIATE CODE: R313111

R350 Written notification of registration of transfer

Free format text: JAPANESE INTERMEDIATE CODE: R350

LAPS Cancellation because of no payment of annual fees