DE102017210376A1 - A vehicle turn determination device and a vehicle travel support device comprising such a vehicle turn determination device - Google Patents

Abstract

The invention relates to a vehicle turn determination device (100) adapted to be mounted in an ego vehicle and to determine that the ego vehicle is making a turn maneuver, wherein the vehicle turn destination Apparatus (100) comprising: a steering angle determination unit (114) configured to provide an output signal indicative of the current steering angle of the ego vehicle, a road-following steering angle determination unit (108), which is arranged to provide an output signal indicative of a road-following steering angle which allows the ego vehicle to follow the road on which it is traveling and a vehicle turn determination unit (112 ) configured to determine, on the basis of the output signals obtained from the steering angle determination unit (114) and the road-following steering angle determination unit (108), that the ego vehicle d Abei is to perform a turn maneuver, if the current steering angle exceeds an effective turn limit angle, which results from a correction of a straight-line-turn limit angle to the road-following steering angle.

Description

The invention relates to a vehicle turn determination device configured to be mounted in an ego vehicle and to determine that the ego vehicle is making a turn maneuver.

Such vehicle turn determination devices may be used, for example, in connection with vehicle ride assist devices, and in particular in conjunction with vehicle ride assist devices configured to avoid the driver of an ego vehicle in avoiding to assist a collision during a turn maneuver. Since the risk of collision is of particular importance during a turn maneuver in which at least one lane of oncoming traffic is crossed, the present invention and its implications will be described in the following with particular reference to this situation. It should be emphasized, however, that the present invention should not be limited thereto.

Turning maneuvers in which at least one lane of oncoming traffic is crossed may occur in both types of traffic systems, the right-hand traffic system and the left-hand traffic system. In right-hand traffic systems, such as Continental Europe and the United States of America, at least one lane of oncoming traffic is crossed during a left-turn maneuver, whereas in left-hand traffic systems such as in Japan and the United Kingdom at least one lane of oncoming traffic is crossed Traffic is crossed during a right-turn maneuver. For the sake of simplicity, the invention will be described below with reference to a right-hand traffic system, in particular when referring to the drawings. To obtain analogue situations for a left-hand traffic system, the situations described for right-hand traffic with respect to the direction of travel of the ego vehicle just before the left-turn maneuver is started may simply be mirrored.

There are many known prior art vehicle turn determination devices that use different approaches to determining whether or not the ego vehicle is performing a turn maneuver. In particular, the present invention pertains to that type of vehicle turn determination apparatus that determines whether or not the instantaneous steering angle of the ego vehicle exceeds a turn limit angle.

It should be noted that in the context of the present invention, a steering angle coordinate system is used, according to which a straight-ahead is indicated by a steering angle of 0 °, whereas a turn to the left is indicated by positive steering angles and a turn to the right by negative steering angles becomes. Of course, other types of coordinate systems may also be used without departing from the scope of the present invention.

Moreover, it should be noted that in the context of the present invention, the steering angle may be the steering wheel steering angle α or the steering angle of the steered wheels δ. Both types of steering angles are related to each other by the fact that the steering angle δ of the steered wheels, in particular of the steered front wheels, is proportional to the steering wheel angle α, the proportionality constant c being the steering ratio of the ego vehicle, which is a parameter which for every vehicle model is unique. For the sake of simplicity only, the description of the present invention will refer to the steering wheel steering angle α. $$\mathrm{\alpha \; =}\text{c}\cdot \mathrm{\delta }$$

In prior art vehicle turn determination devices, a turn-off threshold of more than 100 ° is usually used to prevent false-positive determination results. As a result, the cruise assistance devices incorporating prior art vehicle turn determination devices sometimes exhibit low performance, particularly late initiation of collision avoidance to prevent collision because of such a high amount of steering for determining that the ego vehicle is performing an oncoming lane intersection turn maneuver is necessary.

In view of the above, it is the object of the present invention to provide a vehicle turn determination apparatus which allows a faster and safer vehicle turn determination.

• eine Lenkwinkel-Bestimmungseinheit, welche dazu eingerichtet ist, ein Ausgabe-Signal bereitzustellen, welches den momentanen Lenkwinkel des Ego-Fahrzeugs anzeigt,
• eine Straßen-Folge-Lenkwinkel-Bestimmungs-Einheit, welche dazu eingerichtet ist, ein Ausgabe-Signal bereitzustellen, welches einen Straßen-Folge-Lenkwinkel anzeigt, welcher es dem Ego-Fahrzeug erlaubt, der Straße zu folgen, auf welcher es sich bewegt, und
• eine Fahrzeug-Abbiege-Bestimmungs-Einheit, welche dazu eingerichtet ist, auf Grundlage der Ausgabe-Signale, welche von der Lenkwinkel-Bestimmungseinheit und der Straßen-Folge-Lenkwinkel-Bestimmungs-Einheit erhalten werden, zu bestimmen, dass das Ego-Fahrzeug dabei ist, ein Abbiege-Manöver durchzuführen, falls der momentane Lenkwinkel einen effektiven Abbiege-Grenzwinkel überschreitet, welcher aus einer Korrektur eines Gerade-Strasse-Abbiege-Grenzwinkels um den Straßen-Folge-Lenkwinkel resultiert.

The inventors have recognized that one of the reasons for the high turn-off threshold used in prior art devices is to avoid false-positive responses that result from the fact that the ego vehicle is prior to performing the Turn maneuver not straight ahead. The inventors have further recognized that the main reason that the ego vehicle does not drive straight before performing the turn maneuver is that the turn maneuver is to be performed in a turn. This knowledge is taken into account A vehicle turn determination device proposed to be mounted in an ego vehicle and to determine that the ego vehicle is making a turn maneuver, the vehicle turn determination device comprising:

• a steering angle determination unit configured to provide an output signal indicating the current steering angle of the ego vehicle,
• a road following steering angle determination unit configured to provide an output signal indicative of a road following steering angle that allows the ego vehicle to follow the road on which it is moving, and
• a vehicle turn determination unit configured to determine that the ego vehicle is there based on the output signals obtained from the steering angle determination unit and the road following steering angle determination unit is to perform a turn maneuver if the instantaneous steering angle exceeds an effective turn limit angle resulting from a correction of a straight-line-turn limit angle about the road-following steering angle.

According to a further embodiment, it is proposed that the vehicle turning determination unit is arranged to calculate the effective turning limit angle by adding the following road steering angle to the straight road turning limit angle, which is a particularly easy way Correcting the straight-line-turn limit angle.

In particular, correcting the straight road turning angle by the following road steering angle allows using a straight road turning angle with a smaller absolute value. For example, the straight-line turning limit angle may be less than or equal to + 75 ° for left turns and greater than or equal to -75 ° for right turns.

In the following, the effect of the present invention will be described with reference to two examples:

1 FIG. 12 shows a situation in which the ego vehicle H is going to make a left-turn maneuver (dotted line) while driving along a left-turn road (dashed line). It is assumed that the road following steering angle α _follow (steering angle for following the dashed line) is + 60 °, while the straight-ahead-left-turning limit angle α _{th, left is} + 75 °. In this situation, an additional steering angle of + 15 ° to exceed the straight-ahead-left-turn limit angle will be sufficient to result in a false-positive turn determination.

According to the present invention, the straight-ahead-left-turn limit angle α _{th, left} of + 75 ° becomes + 60 ° through the road-following steering angle α _follow to an effective left-turn limit angle α _{eff, th, left} corrected by + 135 °. Therefore, an additional steering angle of + 75 ° or more is required to obtain a left-turn determination result.

2 Fig. 10 shows a situation in which the ego vehicle H is going to make a left-turn maneuver (dotted line) while traveling along a right-turn road (dashed line). Assume that the road following steering angle α _{follow is} -60 ° while the straight-ahead-left-turning limit angle α _{th, left is} + 75 °. In this situation, an additional steering angle of + 135 ° will be required to exceed the straight-ahead-left-turn limit angle, thus leading to a false negative turn determination for lower additional steering angles.

According to the present invention, the straight-ahead-left-turn limit angle α _{th, left} of + 75 ° becomes the road following steering angle α _follow of -60 ° to an effective left-turn limit angle α _{eff, th, left} corrected by + 15 °. Therefore, an additional steering angle of + 75 ° or more is required to obtain a left-turn determination result.

Of course, similar considerations can be applied to situations in which the ego vehicle is about to make a right turn maneuver. Accordingly, the vehicle turning determination unit may be configured to determine that the vehicle is making a left turn maneuver if the current steering angle α is greater than an effective left turn limit angle α _{eff, th, left} , and determine that the vehicle is making a right turn maneuver if the current steering angle α is less than an effective right turn limit angle α _{eff, th, right} .

It should be noted that the road following steering angle α _{follow may be determined} on the basis of the curvature κ of the road on which the ego vehicle is traveling. This will be with reference to 3 described in greater detail, which shows the so-called Ackermann geometry:

The curvature κ and the radius R of the road on which the ego vehicle is traveling are related by the following equation: $$\mathrm{\kappa \; =\; 1}/\text{R}$$

und einer Radbasis a, welche ein Parameter ist, welcher für jedes Fahrzeugmodell einzigartig ist, gemäß der folgenden Gleichung berechnet werden: $$\text{R}=\text{a}\cdot \text{tan}\left(\mathrm{\delta }\right)$$

oder durch Auflösen nach dem Lenkwinkel der gelenkten Räder δ: $$\mathrm{\delta }=\text{arctan}\left(\text{R}/\text{a}\right)$$

und durch Einsetzen von Gleichung (2): $$\mathrm{\delta }=\text{arctan}\left(\text{a}\cdot \mathrm{\kappa }\right)$$

Since the ego vehicle follows the road, the radius R can be calculated from the mean steering angle of the steered wheels 5 of the ego vehicle, which is the mean value of the steering angle δ ₁ the left steered wheel and the steering angle δ ₂ the left steered wheel is, $$\mathrm{\delta }=\left({\mathrm{<figure-callout\; id="1"\; label="\delta "\; filenames="DE102017210376A1\_0013.png"\; state="\{\{state\}\}">\delta </figure-callout>}}_1+{\mathrm{\delta }}_2\right)/2$$

and a wheel base a, which is a parameter unique to each vehicle model, calculated according to the following equation: $$\text{R}=\text{a}\cdot \text{tan}\left(\mathrm{\delta }\right)$$

or by dissolving according to the steering angle of the steered wheels δ: $$\mathrm{\delta }=\text{arctan}\left(\text{R}/\text{a}\right)$$

and by substituting equation (2): $$\mathrm{\delta }=\text{arctan}\left(\text{a}\cdot \mathrm{\kappa }\right)$$

By combining the equations (1) and (4b), a formula can be obtained which correlates the road-following steered-wheel steering angle and the road curvature α _follow : $${\mathrm{\alpha }}_{\text{follow}}=\text{c}\cdot \text{arctan}\left(\text{a}\cdot \mathrm{\kappa }\right)$$

Information about the curvature κ of the road can be obtained in several ways:

For example, the road following steering angle determination unit may be configured to receive map data from a map data providing unit, for example, the map portion of a navigation system installed in the ego vehicle.

Additionally or alternatively, however, it is also conceivable that the road-following steering angle determination unit is adapted to receive environmental monitoring data from an environmental monitoring unit which is adapted to monitor the environment of the ego vehicle and corresponding Provide environmental monitoring data.

For example, the environmental monitoring unit may include at least one environmental monitoring sensor attached to the ego vehicle, for example, a camera, a radar system, a lidar system, a GPS system, or the like. Such environmental monitoring sensors may be shared with another vehicle travel assistance device, such as a lane keeping assistance device. Additionally or alternatively, however, the environmental monitoring unit may include a communication unit configured to communicate with at least one environmental monitoring sensor mounted outside the ego vehicle, for example, using C2X communication. The curvature of the road may be determined based on the environmental monitoring data provided by these sensors and / or by the communication unit, for example by detecting lane markers (camera) and / or by trajectory tracing from other vehicles (radar, lidar , Camera) and / or by detecting free spaces in which can be driven (radar, lidar, camera) and / or by detecting static objects, such as parked vehicles (radar, lidar, camera) and / or by using transmitted geometry information (C2X communication).

However, it is also conceivable that the road-following steering angle is determined directly from the above-mentioned data, that is, without previously determining the curvature.

As already mentioned, the invention further relates to a vehicle drive-assist device, which has a vehicle turn-determining device. Device according to the present invention comprises.

• 1 ein Beispiel eines Ego-Fahrzeugs zeigt, welches dabei ist, ein Links-Abbiege-Manöver durchzuführen, während es sich in einer Linkskurve bewegt;
• 2 ein Beispiel eines Ego-Fahrzeugs zeigt, welches dabei ist, ein Links-Abbiege-Manöver durchzuführen, während es sich in einer Rechtskurve bewegt;
• 3 ein Diagramm zeigt, welches die Ackermann-Lenkgeometrie darstellt;
• 4 ein Blockdiagramm einer Fahrzeug-Fahrt-Unterstützungs-Vorrichtung zeigt, welche eine Fahrzeug-Abbiege-Bestimmungs-Vorrichtung gemäß der vorliegenden Erfindung umfasst; und
• 5 ein Flussdiagramm zeigt, welches den Betrieb der Fahrzeug-Abbiege-Bestimmungs-Vorrichtung gemäß der vorliegenden Erfindung darstellt.

In the following, the following invention will be described in more detail with reference to the attached drawings, in which

• 1 shows an example of an ego vehicle going to perform a left turn maneuver while moving in a left turn;
• 2 shows an example of an ego vehicle going to perform a left turn maneuver while moving in a right hand turn;
• 3 a diagram showing the Ackermann steering geometry;
• 4 10 shows a block diagram of a vehicle trip assist device including a vehicle turn determination device according to the present invention; and
• 5 FIG. 10 is a flowchart illustrating the operation of the vehicle turning determination device according to the present invention. FIG.

4 shows a block diagram of the vehicle turning determination device 100 according to the present invention.

The Vehicle Turn Determination Device 100 includes an environmental monitoring unit 102 which is adapted to the environment of the ego vehicle H to monitor (see 1 to 3 ). For example, the environment monitoring unit 102 at least one environmental monitoring sensor 104 which is on the ego vehicle H attached, for example a camera, a radar system, a lidar system, a GPS system or the like, and / or at least one communication unit 106 which is adapted to communicate with at least one environmental monitoring sensor (not shown) which is external to the ego vehicle H appropriate, for example using a C2X communication technology.

The output data generated by the environmental monitoring unit 102 are provided to a road-following steering angle determination unit 108 which is adapted to provide an output signal indicative of a road following steering angle α _follow which gives it to the ego vehicle H allowed to follow the road on which it moves. In addition, the road following steering angle determination unit 108 with a map data providing unit 110 connected, for example, the map portion of a navigation system, which in the ego vehicle H is installed.

The road following steering angle α _follow , which is determined by the road-following steering angle determination unit 108 is determined is to a vehicle turn determination unit 112 which is adapted to, based on the output signals, which from a steering angle determination unit 110 and the road following steering angle determination unit 108 to be determined, whether or not the ego vehicle H doing is to do a turn-maneuver.

Hereinafter, the determination process performed by the vehicle turning determination device 100 is executed with reference to 5 to be discribed:

In step S1 For example, the process is started, for example, triggered by a timer signal which is output by a timer (not shown).

In step S2 All the data required for permitting the road-following steering angle determination unit 108 are required to determine the current road following steering angle α _follow from the corresponding sensors or data providing units 102 . 104 . 106 and 110 receive.

Further, the road following steering angle determination unit determines 108 the road following steering angle α _follow based on these data using the formulas and equations described above.

$${\mathrm{\alpha }}_{\text{eff}\text{,th}\text{,right}}={\mathrm{\alpha }}_{\text{th}\text{,richt}}+{\mathrm{\alpha }}_{\text{follow}}$$

Then the process moves to step S3 in which the effective left-turn limit angle α _{eff, th, left is added} by adding the road-following steering angle α _follow to the straight-ahead-left-turn limit angle α _{th, left} (for example, α _{th, left} = + 75 °), and the effective right turn limit angle α _{eff, th, right} by adding the road following steering angle α _follow to the straight-ahead-left-turn limit angle α _{th, right} (for example, α _{th, right} = -75 °). $${\mathrm{\alpha }}_{\text{eff}\text{th}\text{, left}}={\mathrm{\alpha }}_{\text{th}\text{, left}}+{\mathrm{\alpha }}_{\text{follow}}$$

$${\mathrm{\alpha }}_{\text{eff}\text{th}\text{, right}}={\mathrm{\alpha }}_{\text{th}\text{, report}}+{\mathrm{\alpha }}_{\text{follow}}$$

Next will be in step S4 determines whether or not the instantaneous steering angle α is greater than the effective left-turn limit angle α _{eff, th, left} (α> α _{eff, th, left} ).

If the answer to step S4 is positive (step S4 : Yes), it is determined that the ego vehicle H turns to the left, and a corresponding value is turned to a turn indicator parameter T in step S5 entered (for example, T = +1). Then the process is in step S6 completed.

If the answer to step S4 is negative (step S4 : No), the process goes to a step S7 in which it is determined whether or not the instantaneous steering angle α is less than the effective right turn critical angle α _{eff, th, right} (α <α _{eff, th, right} ).

If the answer to step S7 is positive (step S7 Yes), it is determined that the first-person vehicle H turns right, and a corresponding value is turned to a turn-display parameter T in step S8 entered (for example, T = -1). Then the process is in step S6 completed.

If the answer to step S7 is negative (step S7 : No), it is determined that the ego vehicle H is not turning, and a corresponding value is turned to a turn indicator parameter T in step S9 entered (for example, T = 0). Then the process is in step S6 completed.

The value of turn indication parameter T may be obtained by other devices or units, for example a vehicle ride assist device 116 , which is adapted to assist the driver of an ego vehicle in avoiding a collision during a turn maneuver, in particular during a turn maneuver in which at least one lane of oncoming traffic is crossed. The control unit 118 may additionally receive input signals from other units, such as a collision risk determination unit 120 , and a brake unit 122 to initiate autonomous emergency braking, and optionally beforehand warning signals to the driver of the ego vehicle via a man-machine interface 124 output.

Claims (9)

A vehicle turn determination device (100) adapted to be mounted in an ego vehicle (H) and to determine that the ego vehicle (H) is making a turn maneuver, the vehicle turns Determination device (100) comprises: a steering angle determination unit (114) which is adapted to provide an output signal indicating the current steering angle (a) of the ego vehicle, a road following steering angle determination unit (108) which is arranged to provide an output signal indicative of a road sequence steering angle (α _follow) indicating which allows the ego vehicle (H), to follow the road on which it moves, and a vehicle turn determination unit (112) arranged to operate based on the output signals supplied from the steering angle determination unit (114) and the following road steering angle determination unit (12). 108) to determine that the ego-Fah (H) is about to perform a turn maneuver if the instantaneous steering angle (a) exceeds an effective turn limit angle (α _{eff, th, left} , α _{eff, th, right} ) resulting from a straight-line correction Bending limit angle (α _{th, left} , α _{th, right} ) results in the road following steering angle (α _follow ). Vehicle Turn Determination Device After Claim 1 wherein the vehicle turn determination unit (112) is adapted to increase the effective turn limit angle (α _{eff, th, left} , α _{eff, th, right} ) by adding the road following steering angle (α _follow ) the straight-line-bend limit angle (α _{th, left} , α _{th, right} ) to calculate. Vehicle Turn Determination Device After Claim 1 or 2 wherein the vehicle turn determination unit (112) is adapted to determine that the ego vehicle (H) is performing a left turn maneuver if the current steering angle (a) is greater than an effective left turn Turning limit angle (α _{eff, th, left} ), and determining that the vehicle is making a right turn maneuver if the instantaneous steering angle (a) is less than an effective right turn limit angle (α _{eff, th, right} ). Vehicle Turn Determination Device After One Of The Claims 1 to 3 wherein the road-following steering angle determination unit (108) is adapted to receive map data from a map data providing unit (110). Vehicle Turn Determination Device After One Of The Claims 1 to 4 wherein the road-following steering angle determination unit (108) is adapted to receive environmental monitoring data from an environmental monitoring unit (102) adapted to monitor the environment of the ego vehicle (H) and provide appropriate environmental monitoring data. Vehicle Turn Determination Device After Claim 5 wherein the environmental monitoring unit (102) comprises at least one environmental monitoring sensor (104) mounted on the ego vehicle (H). Vehicle Turn Determination Device After Claim 5 or 6 wherein the environmental monitoring unit (102) comprises a communication unit (106) configured to communicate with at least one environmental monitoring sensor mounted outside the ego vehicle (H). Vehicle Turn Determination Device After One Of The Claims 1 to 7 where the straight-line-bend limit angle (α _{th, left} , α _{th, right} ) is less than or equal to + 75 ° for left turns and greater than or equal to -75 ° for right turns. A vehicle ride assist device (116) adapted to be mounted in an ego vehicle (H) and the driver of an ego vehicle to avoid a collision during a turn maneuver, in particular during a turn maneuver in which at least one track of The vehicle ride support device (116) comprises a vehicle turn determination device (100) according to one of the preceding claims.

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