DE102017009532A1 - Method for setting a desired distance between motor vehicles - Google Patents

Abstract

The invention relates to a method for setting a desired distance (d_setpoint) between a preceding first motor vehicle (10) and a second motor vehicle (20) traveling behind the first motor vehicle (10), comprising at least the following steps: determining an actual distance (d_Ist) between the first motor vehicle (10) and the second motor vehicle (20);

Description

The invention relates to a method for setting a desired distance between a preceding first motor vehicle and a second motor vehicle traveling behind the first motor vehicle.

To avoid rear-end collisions, spacing systems are used in modern motor vehicles, by means of which a speed-dependent minimum distance between a vehicle in front and a driving behind it can be adjusted.

From the DE 10 2016 006 523 A1 For example, a method for adjusting a distance between a following vehicle and a preceding vehicle is known. The adjustment of the distance is made depending on whether the vehicles are going downhill or uphill, depending on a respective vehicle weight of the vehicles, and depending on a respective engine of the vehicles.

Object of the present invention is to provide a method of the type mentioned, by which a particularly favorable flow of traffic can be ensured.

This object is achieved by a method having the features of patent claim 1. Advantageous embodiments with expedient developments of the invention are specified in the remaining claims.

• - Ermitteln eines Ist-Abstands zwischen dem ersten Kraftfahrzeug und dem zweiten Kraftfahrzeug;
• - Einstellen des Soll-Abstands in Abhängigkeit von dem Ist-Abstand und einer Differenzgeschwindigkeit zwischen dem ersten Kraftfahrzeug und dem zweiten Kraftfahrzeug, indem eine erste Geschwindigkeit des ersten Kraftfahrzeugs erhöht und dadurch an eine zweite Geschwindigkeit des zweiten Kraftfahrzeugs angepasst wird.

A method according to the invention for setting a desired distance between a preceding first motor vehicle and a second motor vehicle traveling behind the first motor vehicle comprises at least the following steps:

• Determining an actual distance between the first motor vehicle and the second motor vehicle;
• - Setting the desired distance as a function of the actual distance and a differential speed between the first motor vehicle and the second motor vehicle, by increasing a first speed of the first motor vehicle and thereby adapted to a second speed of the second motor vehicle.

This is advantageous since, by increasing the first speed of the first motor vehicle, braking of the second motor vehicle approaching the second speed can thus be avoided, thereby ensuring an improved flow of traffic.

The invention is based on the finding that a braking of vehicles traveling behind, as known from the prior art, leads to a negative influence on the traffic flow due to slower driving vehicles ahead. In order to avoid a backwater or a "concertina effect" of several vehicles driving one behind the other, the setpoint distance is adjusted by adjusting the first speed (of the preceding, first motor vehicle) to the second speed of the vehicle behind the first motor vehicle , second motor vehicle. By avoiding braking activities of the second motor vehicle, a particularly energy-saving operation is possible in addition to the favorable traffic flow.

The first motor vehicle can measure the actual distance, for example, by means of an in-vehicle distance sensor, which can be designed, for example, as a radar sensor. In other words, therefore, the preceding, first motor vehicle can determine the actual distance to the second motor vehicle approaching from behind. The approaching from the rear second motor vehicle can transmit its second speed to the first slower moving first motor vehicle.

According to the value of the actual distance and the transmitted second speed, the first motor vehicle can accelerate in such a way that the second motor vehicle can maintain its second speed without decelerating. The first motor vehicle can accelerate until the differential speed between the first motor vehicle and the second motor vehicle assumes the value "zero", in other words, until the first speed corresponds to the second speed.

In an advantageous development of the invention, the first speed is adjusted as a function of a predetermined speed limit to the second speed. This is advantageous because, due to the adaptation as a function of the predetermined speed limit, a particularly high level of traffic safety when setting the desired distance is ensured.

The predefined speed limit can be, for example, a maximum permissible speed limit.

However, the predetermined speed limit may also be an individually predetermined, that is predetermined by a vehicle occupant speed limit. Thus, the vehicle occupant can specify a personal, maximum speed limit that is personally determined for him, if the vehicle occupant fears or expects a malaise in case of exceeding the individual speed limit.

In a further advantageous embodiment of the invention, a speed of the two motor vehicles is increased after setting the desired distance and thereby the speed of the two motor vehicles adapted to a speed of a third motor vehicle, which travels behind the two motor vehicles. The first motor vehicle and the second motor vehicle can each be accelerated uniformly until both motor vehicles reach the speed of the third motor vehicle, that is, until the first motor vehicle and the second motor vehicle, in other words, travel at the speed of the third motor vehicle.

After setting the desired distance, a speed of the three motor vehicles can then be increased and thereby the speed of the three motor vehicles can be adapted to a speed of a fourth motor vehicle or of any other motor vehicles driving or following the three motor vehicles. As a result, a total of a column of four or more vehicles can be formed without affecting the flow of traffic.

In a further advantageous embodiment of the invention, at least the first motor vehicle is operated autonomously. This is advantageous, since a particularly accurate setting of the desired distance while maintaining a particularly high road safety can be achieved here. The second motor vehicle traveling behind the first motor vehicle and further motor vehicles driving behind the first and the second motor vehicle can be equipped, for example, by means of a conventional spacing system and drive behind the first motor vehicle. However, the second motor vehicle or other motor vehicles can also be operated autonomously, whereby a particularly high road safety can be achieved. Autonomous vehicles can generally drive without manual driver intervention and thus automatically.

Preferably, the first motor vehicle is operated fully autonomously. This allows the setting of the desired distance particularly fast and accurate.

A particularly favorable traffic flow can be achieved if all motor vehicles are operated fully autonomously when carrying out the method.

Further advantages, features and details of the invention will become apparent from the following description of a preferred embodiment and from the drawing (s). The features and feature combinations mentioned above in the description as well as the features and feature combinations mentioned below in the figure description and / or alone in the single figure can be used not only in the respectively indicated combination but also in other combinations or alone, without the frame to leave the invention.

• 1 eine schematische Darstellung zweier Kraftfahrzeuge, welche mit unterschiedlichen Geschwindigkeiten hintereinander fahren, wobei ein erstes Kraftfahrzeug der beiden Kraftfahrzeuge mit einer im Vergleich zu einer zweiten Geschwindigkeit des zweiten Kraftfahrzeugs der beiden Kraftfahrzeuge geringeren ersten Geschwindigkeit fährt;
• 2 eine weitere schematische Darstellung der beiden Kraftfahrzeuge, welche nach Einstellung eines Soll-Abstands beide mit der zweiten Geschwindigkeit fahren;
• 3 eine weitere schematische Darstellung der beiden Kraftfahrzeuge, an welche sich ein drittes Kraftfahrzeug mit einer dritten Geschwindigkeit von hinten annähert;
• 4 eine weitere schematische Darstellung des ersten Fahrzeugs, des zweiten Fahrzeugs und des dritten Fahrzeugs, welche hintereinander fahren und an welche sich ein viertes Fahrzeug mit einer vierten Geschwindigkeit von hinten annähert; und
• 5 eine weitere schematische Darstellung der in 4 gezeigten Fahrzeuge, welche jeweils mit der vierte Geschwindigkeit fahren.

Showing:

• 1 a schematic representation of two motor vehicles, which drive at different speeds in succession, wherein a first motor vehicle of the two motor vehicles moves with a lower compared to a second speed of the second motor vehicle of the two motor vehicles first speed;
• 2 a further schematic representation of the two motor vehicles, which both travel at the second speed after setting a desired distance;
• 3 a further schematic representation of the two motor vehicles, to which a third motor vehicle approaches at a third speed from behind;
• 4 another schematic representation of the first vehicle, the second vehicle and the third vehicle, which drive behind each other and to which a fourth vehicle with a fourth speed approaches from behind; and
• 5 another schematic representation of in 4 shown vehicles, which each drive at the fourth speed.

The following 1 to 5 serve to illustrate a method for setting a desired distance D_SETP between a preceding first motor vehicle 10 and one behind the first motor vehicle 10 driving, second motor vehicle 20 as well as further, behind the two motor vehicles 10 . 20 moving motor vehicles, namely a third motor vehicle 30 and a fourth motor vehicle 40 ,

At least the first motor vehicle 10 is operated autonomously, so that the first motor vehicle 10 regardless of driver intervention to changing traffic situations.

1 shows a state in which the first motor vehicle 10 at a first speed v_1 drives and behind the first motor vehicle 10 the second motor vehicle 20 at a second speed v_2 drives, where is an actual distance d_Ist between the two cars 10 . 20 changes, since the second speed v_2 is greater than the first speed v_1 , In the in 1 shown state may be the second speed v_2 for example, a value of 60 km / h and the first speed v_1 correspond to a value of 50 km / h.

By a distance sensor of the first motor vehicle 10 becomes the actual distance d_Ist between the first motor vehicle 10 and the second motor vehicle 20 measured.

Depending on the measured actual distance d_Ist and a differential speed between the first motor vehicle 10 and the second motor vehicle 20 followed by a setting of the desired distance D_SETP by the first speed v_1 of the first motor vehicle 10 increased and thereby to the second speed v_2 of the second motor vehicle 20 is adjusted. The differential speed can also be considered the difference of the second speed v_2 and the first speed v_1 be designated.

Once setting the target distance D_SETP is completed, drive both vehicles 10 . 20 at the second speed v_2 of the second motor vehicle 20 , which is why the target distance D_SETP between the two cars 10 . 20 no longer changes, as in 2 is shown.

The first speed v_1 generally becomes dependent on a predetermined speed limit to the second speed v_2 customized.

3 shows a state in which a common speed v_12 the two motor vehicles 10 . 20 is increased and thereby the speed v_12 the two motor vehicles 10 . 20 to a third speed V_3 of the third motor vehicle 30 which is adapted to the two motor vehicles 10 . 20 approaching from behind, so behind.

The speed V_3 in this case corresponds to a value of 70 km / h. Adjusting the speed v_12 can after setting the target distance D_SETP , but also during the setting of the target distance D_SETP between the two cars 10 . 20 respectively. By the possibility of the speed v_12 the two motor vehicles 10 . 20 while setting the target distance D_SETP It can be particularly dynamic for changing traffic situations, that is to say, at the third speed V_3 approximate, third motor vehicle 30 be reacted, with a distance setting e the two preceding vehicles 10 . 20 relative to the third motor vehicle 30 he follows.

At the distance adjustment e fit the two cars 10 . 20 their speed v_12 to the third speed V_3 by acceleration, until finally all three motor vehicles 10 . 20 . 30 - as in 4 shown - at a common speed v_123 drive, which is the third speed V_3 equivalent.

After or while setting the desired distance D_SETP will the speed v_123 of the three motor vehicles 10 . 20 . 30 increases and thereby the speed v_123 of the three motor vehicles 10 . 20 . 30 at a speed V_4 of the fourth motor vehicle 40 adapted, which is the three motor vehicles 10 . 20 . 30 approaching from behind, so the three vehicles 10 . 20 . 30 after driving. The speed V_4 in this case corresponds to a value of 100 km / h.

The common speed v_123 of the three motor vehicles 10 . 20 . 30 will now be part of the distance adjustment e increases until the common speed v_123 the fourth speed V_4 of the fourth motor vehicle 40 corresponds, as in 5 is shown.

In 5 Finally, drive all four vehicles 10 . 20 . 30 . 40 in compliance with the target distance D_SETP with the now common speed V_4 in a column.

The present method generally enables optimization of traffic flow by avoiding unnecessary braking in mixed traffic autonomously (automatically) and non-autonomously driving vehicles.

LIST OF REFERENCE NUMBERS

10

first motor vehicle

20

second motor vehicle

30

third motor vehicle

40

fourth motor vehicle

d_Ist

Actual distance

D_SETP

Target distance

v_1

first speed

v_2

second speed

V_3

third speed

V_4

fourth speed

v_12

(common) speed of 10 and 20

v_123

(common) speed of 10, 20 30

e

distance adjustment

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102016006523 A1 [0003]

Claims (5)

Method for setting a desired distance (d_setpoint) between a preceding first motor vehicle (10) and a second motor vehicle (20) traveling behind the first motor vehicle (10), comprising at least the following steps: Determining an actual distance (d_Ist) between the first motor vehicle (10) and the second motor vehicle (20); Setting the desired distance (d_Soll) as a function of the actual distance (d_Ist) and a differential speed between the first motor vehicle (10) and the second motor vehicle (20) by a first speed (v_1) of the first motor vehicle (10) is increased and thereby adapted to a second speed (v_2) of the second motor vehicle (20). Method according to Claim 1 , characterized in that the first speed (v_1) is adjusted as a function of a predetermined speed limit to the second speed (v_2). Method according to Claim 1 or 2 characterized in that after setting the desired distance (d_Soll) a speed (v_12) of the two motor vehicles (10, 20) is increased, and thereby the speed (v_12) of the two motor vehicles (10, 20) at a speed ( v_3) of a third motor vehicle (30) is adjusted, which travels behind the two motor vehicles (10, 20). Method according to Claim 3 characterized in that after setting the target distance (d_soll) a speed (v_123) of the three motor vehicles (10, 20, 30) is increased, and thereby the speed (v_123) of the three motor vehicles (10, 20, 30) is adapted to a speed (v_4) of a fourth motor vehicle (40) which travels behind the three motor vehicles (10, 20, 30). Method according to one of the preceding claims, characterized in that at least the first motor vehicle (10) is operated autonomously.

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