DE102020004196A1 - Speed limit for trucks when turning - Google Patents

Abstract

The invention relates to a driver assistance system (1) for limiting the speed of a vehicle (3) when turning, in particular a truck, having a speed control unit (7) which controls a drive and / or a brake in such a way that one of a control unit (5) predetermined maximum permissible speed is not exceeded, the control unit (5) prescribing the predefined maximum permissible speed when the control unit (5) detects a turning maneuver of the vehicle (3), and the specification of the predefined maximum permissible speed is only canceled when the turning maneuver is finished.

Description

The invention relates to a driver assistance system for limiting a speed of a vehicle when turning and to a vehicle with such a driver assistance system.

When turning a vehicle at an intersection or into a driveway, the driver of the turning vehicle usually has to watch out for pedestrians and cyclists crossing the street or driveway into which the vehicle is turning. Particularly in the case of trucks and other longer vehicles with trailers such as construction site vehicles, there is a risk for the driver of, for example, overlooking a pedestrian or cyclist and colliding with him.

The DE 10 2009 041 555 A1 relates to a method for warning a vehicle driver of an object. In this method, the following steps take place: monitoring a surrounding area of a vehicle, unconditionally warning the vehicle driver if a moving object is detected in the monitored surrounding area, determining a driving corridor if a stationary object is detected in the monitored surrounding area, and warning the vehicle driver if the stationary object is in the driving corridor.

The object of the invention is to increase the safety when turning a vehicle, in particular a truck.

The invention results from the features of the independent claims. The dependent claims relate to advantageous developments and refinements.

A first aspect of the invention relates to a driver assistance system for limiting the speed of a vehicle when turning, in particular a truck, having a control unit and a speed control unit, the speed control unit being designed to control a drive and / or a brake of the vehicle in such a way that one of the maximum permissible speed specified by the control unit is not exceeded, the control unit being designed to specify a predefined maximum permissible speed, in particular walking speed, for the speed control unit when the control unit detects a turning maneuver of the vehicle, and only then cancel the specification of the predefined maximum permissible speed when a predetermined condition for the completion of the turning process is met.

The control unit and the speed regulation unit are each implemented as logical units on a common carrier for an integrated circuit (IC). The speed control unit includes, in particular, a control loop with a logic circuit which is designed to prevent the vehicle from traveling at speeds above the predetermined maximum permissible speed. The driver of the vehicle feels, in particular when pressing the accelerator pedal at and above the predefined maximum permissible speed, that his input on the accelerator pedal does not lead to an increase in the speed of the vehicle as is otherwise usual. Rather, that part of the input on the accelerator pedal which would accelerate the vehicle beyond the maximum permissible speed remains ineffective. The cruise control unit submits this by cutting off an in particular electronically recorded input on the accelerator pedal (for example position and / or speed at which the accelerator pedal is actuated by the driver) and / or by actuating a brake. While on a horizontal road, after accelerating the vehicle from a standstill, it is typically sufficient to limit the drive power of the vehicle so that the speed of the vehicle is at most constant, but does not increase beyond the predefined maximum permissible speed. That is, when the vehicle is going downhill, it is generally necessary to actuate a brake of the vehicle if the rolling resistance and the air resistance, which is still small at these speeds, do not sufficiently compensate for the drive power and the downhill force of the vehicle.

A mechanical brake can also be a truck retarder. Instead of a mechanical brake, in the case of electric vehicles, an electric brake can also be used, in which case the electric drive of the vehicle is typically also designed for recuperation. This is achieved by reversing the function of an electric motor into an electric brake through generator operation, in which electricity is generated at the drive and thus the vehicle's battery is charged.
The predefined maximum permissible speed of the vehicle is preferably selected as “walking speed”, that is to say preferably 11 km / h, particularly preferably as a value in the range from 4 to 7 km / h. A value for the specification of the maximum permissible speed is in particular stored in advance in the control unit and can preferably be reset at least by workshop personnel. This is particularly advantageous when a value of a maximum permissible speed, in particular for Trucks specified or such a legal requirement is changed.

By the control unit determining a specification for the speed control unit, the control unit activates the function of the speed control unit so that the latter ensures compliance with the maximum permissible speed of the vehicle. If this specification of the maximum permissible speed is canceled by the control unit, this function of the cruise control unit is deactivated and the vehicle can exceed the maximum permissible speed again.

It is an advantageous effect of the invention that a driver of the vehicle is made easier during a turning maneuver to observe his surroundings instead of being forced to keep the speed of the vehicle with divided attention and at the same time to pay attention to the surroundings. This advantageously increases safety when turning, so that the typical risk of accidents when turning, in particular a collision with cyclists or pedestrians, are reduced.

Forcing compliance with the maximum permitted speed can be combined with other assistance systems in the vehicle. In particular, an emergency brake assistant can be activated if pedestrians, cyclists or other road users are in the current or planned path of the vehicle during the turning process or if they cross it in such a way that a collision with the vehicle would occur. For this prediction of the path of the vehicle, the route planned by the navigation system for the vehicle is preferably used in order to then compare it with the predicted path of another road user.

According to an advantageous embodiment, the control unit is designed to specify the predefined maximum permissible speed for the speed control unit only when a steering angle of the vehicle exceeds a predetermined limit value. According to this embodiment, when a pending turning maneuver of the vehicle is detected, the predefined maximum permissible speed is only specified and actively tracked by the speed control unit when there is a correspondingly large steering angle of the vehicle. For example, if the position of the vehicle at an intersection is recognized from map data and satellite-based positioning, at which the vehicle is turning according to the route planned from the navigation system, the driver of the vehicle and the general traffic flow would hardly tolerate it if the maximum permissible speed is enforced well before the start of the turning maneuver. Rather, what is advantageously achieved by this embodiment is that the maximum permissible speed is only actually ensured when the vehicle is turning, that is, when the vehicle is cornering.

According to a further advantageous embodiment, the speed control unit is designed to limit the drive power of the drive of the vehicle in such a way that an acceleration of the vehicle above the maximum permissible speed caused by the drive power is prevented, and the brake of the vehicle is applied at a speed above the maximum permissible speed activate and / or activate a recuperation function of the electric drive in the case of an electric drive of the vehicle.

The limitation of the drive power has the advantageous effect that an actuation of the accelerator pedal by the driver does not actually cause an increased torque on the drive of the vehicle, which would be destroyed by the cruise control unit through mechanical or electrical braking, but that from the beginning only that part of the actuation the accelerator pedal actually leads to an acceleration of the vehicle, which does not lead to the maximum permissible speed being exceeded when turning.

• - das Erreichen einer vorgegebenen Strecke des Fahrzeugs, die das Fahrzeug beim Abbiegen seit Beginn der Vorgabe der höchstzulässigen Geschwindigkeit für die Geschwindigkeitsregeleinheit zurückgelegt hat,
• - das Durchschreiten einer vorgegebenen Schwelle im Lenkwinkel mit der Tendenz von einem größeren zu einem kleineren Lenkwinkel,
• - das Deaktivieren eines Fahrtrichtungsanzeigers,
• - das Erkennen des Endes des Abbiegevorgangs auf Basis einer von der Ortungseinheit erfassten Position unter Abgleich von Kartendaten,
• - das Umlegen eines Eingabeelements in seinen deaktivierten Zustand durch einen Fahrer des Fahrzeugs.

According to a further advantageous embodiment, the predefined condition for ending the turning process is one of the following or a combination of the following:

• - the vehicle has reached a specified distance that the vehicle has covered when turning since the start of the specification of the maximum permissible speed for the cruise control unit,
• - Crossing a given threshold in the steering angle with the tendency from a larger to a smaller steering angle,
• - the deactivation of a direction indicator,
• - the detection of the end of the turning process on the basis of a position recorded by the locating unit with comparison of map data,
• the switching of an input element into its deactivated state by a driver of the vehicle.

The distance covered by the vehicle during the turning process is preferably calculated by odometry, that is to say based on a known wheel diameter and the detected revolutions of the respective wheel, the distance covered by the respective wheel is determined. Alternatively, the distance covered is preferably determined with the aid of the odometer installed as standard in the vehicle; as an alternative, the distance covered is also determined on the basis of a navigation system, in particular a satellite navigation system, such as NAVSTAR or GLONASS. As an alternative, the distance covered is also determined on the basis of camera data and / or lidar data. The direction indicator is also known colloquially as a blinker. Fulfillment of a combination of these individual conditions is preferably used as a predetermined condition.

The distance covered relates in particular to a rear end of the vehicle, so that it is advantageously ensured that the entire vehicle has completed the turning process in its full length. The length of the vehicle is preferably stored; alternatively, it is preferably recognized by the control unit, for example by means of a sensor on a trailer coupling that recognizes whether a trailer is attached, or by a mass estimator that compares the current drive power with the actual acceleration of the vehicle .

• - Kameradaten, insbesondere einer Kreuzung und/oder einer von Rot auf Grün wechselnden Ampel an der Kreuzung;
• - Lidardaten,
• - Radardaten,
• - Ultraschalldaten,
• - Lenkwinkeldaten, insbesondere Muster in den Lenkwinkeldaten, insbesondere ein Einschlagen in einen ersten Lenkwinkel gefolgt von einem Einschlagen in einen dem ersten Lenkwinkel entgegen gesetzten zweiten Lenkwinkel,
• - Daten des Fahrtrichtungsanzeigers.

According to a further advantageous embodiment, the control unit is designed to recognize the turning process on the basis of one of the following sensor data or on the basis of a combination of at least two of the following sensor data:

• Camera data, in particular an intersection and / or a traffic light changing from red to green at the intersection;
• - Lidar data,
• - radar data,
• - ultrasound data,
• - Steering angle data, in particular patterns in the steering angle data, in particular turning into a first steering angle followed by turning into a second steering angle opposite to the first steering angle,
• - Data from the direction indicator.

The lidar data, radar data and ultrasound data in particular record a family of distances to surface points of objects and people in the vicinity of the vehicle. From this distance data, the control unit can then calculate environmental data that can be interpreted analytically. In particular, models of the environment can be generated from this, which particularly include the roadway and road users. The camera data preferably include the color-recognized states of a traffic light and, in the case of a stereo camera unit, also spatial data of the environment, in particular including the position and / or speed of other road users. The data of the direction indicator contain, in particular, the information as to whether such a direction indicator is activated, that is, a turn signal of the vehicle is switched on, and if so, on which side of the vehicle. The steering angle data, on the other hand, contain the information about the angle at which one or more steerable wheels are in particular with respect to a straight position for straight-ahead travel of the vehicle. A turning process is preferably recognized when steerable wheels are initially turned into a first steering angle, and then these wheels are turned into a second steering angle opposite to the first steering angle. For example, a semi-trailer truck must first turn left in order to drive through a tight right-hand bend so as not to cause any collisions with the trailer inside the bend.

According to a further advantageous embodiment, the control unit is designed to specify a maximum permissible speed for the turning process for the speed control unit only when a switch provided for this is in its activating position or in an activating state and / or when a traffic sign recognition unit has recognized a town entrance sign , especially before the corresponding exit sign was recognized.

According to a further advantageous embodiment, the control unit is designed to recognize the turning process on the basis of map data in connection with a position determined by a location unit of the vehicle, in particular on the basis of a comparison of the currently determined position of the vehicle in relation to a planned route of the vehicle . According to this embodiment, the turning process is recognized in particular when the vehicle is located at a position at which the vehicle will turn according to the planned route of the vehicle. This detection can be linked to further conditions, for example only if, as explained above, certain patterns are present in the steering angles of steerable wheels. This advantageously verifies that the vehicle is actually executing a turning process.

According to a further advantageous embodiment, the driver assistance system has an output unit, the output unit being designed to be an optical and / or Output an acoustic and / or haptic signal to the driver of the vehicle when the control unit specifies a maximum permissible speed for the cruise control unit.

According to a further advantageous embodiment, the control unit is designed to cancel the specification of the predefined maximum permissible speed in response to an input by the driver in order to overwrite the specification, regardless of whether the specified condition with regard to the end of the turning process is met. Such an override process, also called “override”, is used in particular for safety in order to enable the driver to leave dangerous situations. The specification is preferably overwritten in this way by a “kickdown” on the accelerator pedal, that is to say by pressing the accelerator pedal beyond a threshold in the direction of its stop.

Another aspect of the invention relates to a vehicle, in particular a truck, with a driver assistance system as described above and below.

Advantages and preferred developments of the proposed vehicle result from an analogous and analogous transfer of the statements made above in connection with the proposed driver assistance system.

Further advantages, features and details emerge from the following description in which at least one exemplary embodiment is described in detail - possibly with reference to the drawing. Identical, similar and / or functionally identical parts are provided with the same reference symbols.

• 1 ein Fahrzeug in einer Situation zur Anwendung des Fahrerassistenzsystems, und
• 2 ein Fahrzeug mit einem solchen Fahrerassistenzsystem gemäß einem Ausführungsbeispiel der Erfindung.

Show it:

• 1 a vehicle in a situation to use the driver assistance system, and
• 2 a vehicle with such a driver assistance system according to an embodiment of the invention.

The representations in the figures are schematic and not to scale.

1 shows a vehicle 3 with a driver assistance system 1 . The vehicle 3 is on a roadway before an intersection. A vehicle navigation system 3 has a route for the vehicle before starting the journey 3 determined. According to the route, the vehicle will 3 turn right at this intersection. The street the vehicle is on 3 turn is crossed by a cycle path. The driver of the vehicle 3 has to pay attention to the road users on this cycle path. In addition, speed limits may be required by law in some countries. Such a driver assistance system 1 is in 2 explained in more detail.

2 shows a driver assistance system 1 on a vehicle 3 . This driver assistance system 1 is used to limit a speed of the vehicle 3 when turning as in 1 explained. The vehicle 3 , a truck, has a control unit 5 and a speed control unit 7th on. The speed control unit 7th is a control loop with switching logic and generates manipulated variables for a hybrid drive of the vehicle 3 . The control of the hybrid drive takes place in such a way that one of the control unit 5 specified maximum permissible speed is not exceeded. The control unit 5 gives the predefined maximum permissible speed at a walking speed of 7 km / h to the speed control unit 7th before if from the control unit 5 a turning maneuver of the vehicle 3 is recognized. The detection of the turning process is based on a multiple condition in that one of the locating unit 11 determined position of the vehicle 3 after comparison with digital map data lying in an area of an intersection is recognized, at which according to the navigation system of the vehicle 3 determined route the turn takes place, and a right direction indicator of the vehicle 3 activated by the driver. However, the predefined maximum permissible speed is specified by the control unit 5 only activated if a camera-based traffic sign recognition unit 9 recognized that a town entrance was passed before an exit of town was recognized. The control unit deduces from this 5 that the vehicle 3 is located in a built-up area within which compliance with the predefined maximum permissible speed is required. The predefined maximum permissible speed is specified by the control unit 5 only canceled when a predefined condition for ending the turning process is met. The condition is divided into two partial conditions, which are connected with a logical "AND". The first partial condition is that the exit from the intersection is recognized by sensor data from a camera unit. The second partial condition is that the direction indicator falls back into its switched-off state by turning the wheels in a narrow area around the straight-ahead position. The speed control unit 7th limits the drive power of the vehicle's hybrid drive while the maximum permissible speed is actively specified 3 so that an evoked acceleration of the vehicle 3 above the maximum permissible speed is prevented. In addition, the Speed control unit 7th if the speed increase above the maximum permissible speed caused by downhill force, the brakes of the vehicle 3 activated. This concerns first of all the recuperation function of the electric drive component of the hybrid drive and, if necessary, also the mechanical brakes of the vehicle 3 . An output unit 13 also gives an optical signal to the driver of the vehicle through an illuminated display 3 off when the control unit 5 for the speed control unit 7th specifies a maximum permissible speed.

Although the invention has been illustrated and explained in more detail by preferred exemplary embodiments, the invention is not restricted by the disclosed examples and other variations can be derived therefrom by the person skilled in the art without departing from the scope of protection of the invention. It is therefore clear that there is a multitude of possible variations. It is also clear that embodiments cited by way of example really only represent examples that are not to be interpreted in any way as a limitation, for example, of the scope, the possible applications or the configuration of the invention. Rather, the preceding description and the description of the figures enable the person skilled in the art to implement the exemplary embodiments in concrete terms, whereby the person skilled in the art, with knowledge of the disclosed inventive concept, can make various changes, for example with regard to the function or the arrangement of individual elements mentioned in an exemplary embodiment, without leaving the scope of protection which is defined by the claims and their legal equivalents, such as further explanations in the description.

List of reference symbols

1

Driver assistance system

3

vehicle

5

Control unit

7th

Speed control unit

9

Traffic sign recognition unit

11

Locating unit

13

Output unit

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was 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.

Patent literature cited

• DE 102009041555 A1 [0003]

Claims (10)

Driver assistance system (1) for limiting the speed of a vehicle (3) when turning, in particular a truck, comprising a control unit (5) and a speed control unit (7), the speed control unit (7) being designed to have a drive and / or a brake of the vehicle (3) so that a maximum permissible speed specified by the control unit (5) is not exceeded, the control unit (5) being designed to specify a predefined maximum permissible speed, in particular walking speed, for the speed control unit (7) if a turning process of the vehicle (3) is recognized by the control unit (5), and the specification of the predefined maximum permissible speed is only canceled when a predetermined condition for ending the turning process is met. Driver assistance system (1) Claim 1 wherein the control unit (5) is designed to specify the predefined maximum permissible speed for the speed control unit (7) only when a steering angle of the vehicle (3) exceeds a predetermined limit value. Driver assistance system (1) according to one of the preceding claims, wherein the speed control unit (7) is designed to limit the drive power of the drive of the vehicle (3) so that an acceleration of the vehicle (3) caused by drive power above the maximum permissible speed is prevented , and to activate the brake of the vehicle (3) at a speed above the maximum permissible speed and / or, in the case of an electric drive of the vehicle (3), to activate a recuperation function of the electric drive. Driver assistance system (1) according to one of the preceding claims, wherein the predetermined condition for the termination of the turning process is one of the following or a combination of the following - the achievement of a predetermined distance by the vehicle (3) that the vehicle (3) has covered when turning since the beginning of the specification of the maximum permissible speed for the speed control unit (7), - Crossing a given threshold in the steering angle with the tendency from a larger to a smaller steering angle, - the deactivation of a direction indicator, - the recognition of the end of the turning process on the basis of a position detected by the locating unit (11) with comparison of map data, - The switching of an input element into its deactivated state by a driver of the vehicle (3). Driver assistance system (1) according to one of the preceding claims, wherein the control unit (5) is designed to recognize the turning process on the basis of at least one of the following sensor data or a combination of at least two of the following sensor data: Camera data, in particular an intersection and / or a traffic light changing from red to green at the intersection; - Lidar data; - radar data; - ultrasound data; Steering angle data, in particular patterns in the steering angle data, in particular turning into a first steering angle followed by turning into a second steering angle opposite to the first steering angle; - Data from the direction indicator. Driver assistance system (1) according to one of the preceding claims, wherein the control unit (5) is designed to specify a maximum permissible speed for the turning process for the speed control unit (7) only when a switch is in its activating position or in an activating state and / or if a traffic sign recognition unit (9) has recognized a town entrance sign. Driver assistance system (1) according to one of the preceding claims, wherein the control unit (5) is designed to recognize the turning process on the basis of map data in connection with a position determined by a locating unit (11) of the vehicle (3), in particular on the basis of a Comparison of the currently determined position of the vehicle (3) in relation to a planned route of the vehicle (3). Driver assistance system (1) according to one of the preceding claims, having an output unit (13), wherein the output unit (13) is designed to output an optical and / or acoustic and / or haptic signal to the driver of the vehicle (3) when the Control unit (5) for the speed control unit (7) specifies a maximum permissible speed. Driver assistance system (1) according to one of the preceding claims, wherein the control unit (5) is designed to cancel the specification of the predefined maximum permissible speed in response to an input by the driver to overwrite the specification, regardless of whether the specified condition with regard to the end of the turning process is satisfied. Vehicle (3), in particular a truck, with a driver assistance system (1) according to one of the preceding claims.

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