DE102012218361A1 - Method for operation of four-wheel, two-axle motor car, involves determining collision risk of car, and making dominant measure that is high criticality of driving conditions and better signal quality of environment data, by coordinator - Google Patents

Abstract

The method involves determining collision risk of a motor car (1) with an object (O) e.g. tree, based on a risk rating by a driving safety coordinator. An avoidance recommendation to a vehicle operator or an avoidance support for the vehicle operator is output or autonomous intervention for switching is performed by the driving safety coordinator based on criticality of driving conditions and signal quality of environment data. A dominant measure that is high criticality of the driving conditions and better signal quality of the environment data, is made by the driving safety coordinator.

Description

The present invention relates to a method for operating a motor vehicle having at least one sensor unit for detecting the environmental conditions and for outputting environmental data, an evaluation unit for evaluating the environmental data and an evaluation unit for recognizing free spaces and objects, their position and movement, as well as with a driving safety coordinator, which determines the risk of collision of the motor vehicle with an object based on a risk assessment.

From the EP 1 735 187 A1 A method for increasing road safety is known. In the prior art system, a supportive maneuver is given during or after a steering maneuver caused by an evasive maneuver, wherein the default can be overridden by the driver at any time. In the case of the previously known method, it is determined on the basis of ambient signals whether there is a driving-dynamics-critical situation or an imminent collision. The method is preferably used in emergency situations for evasive maneuvers. An evaluation of the ambient signals does not take place.

It is an object of the present invention to improve a method of the type mentioned in that an evaluation of the signal quality of the environment data is made.

This object is achieved by a method having the features of independent patent claim 1. It is proposed a method for safe operation of a motor vehicle, in which the driving safety coordinator on the basis of the criticality of the driving situation and the signal quality of the surrounding data a fallback recommendation to the driver or an evasion support for the driver or performs an autonomous intervention to evade, the driving safety coordinator a more dominant measure, the higher the criticality of the driving situation and the better the signal quality of the environmental data.

• – eine Ausweichunterstützung für den Fahrzeugführer ausgibt, wenn die Signalgüte der Umfelddaten gering ist,
• – eine Ausweichempfehlung an den Fahrzeugführer ausgibt sowie das Ausweichen unterstützt, wenn die Signalgüte der Umfelddaten einen mittleren Wert aufweist und
• – einen autonomen Eingriff zum Ausweichen durchführt, wenn die Signalgüte der Umfelddaten ausreichend gut ist.

The crucial concept of the invention is that the driving safety coordinator assumes the executive power over the motor vehicle, the higher the criticality of the driving situation and the better the signal quality of the environment data, the driving safety coordinator

• - outputs a fallback support for the driver when the signal quality of the environment data is low,
• - Issues a fallback recommendation to the vehicle driver and supports dodging if the signal quality of the surrounding data has a medium value and
• - Carries out an autonomous intervention for evasion, if the signal quality of the environment data is sufficiently good.

In a further development of the concept of the invention, it is provided that the signal quality of the environmental data is improved by means of a data fusion of further data.

It is provided that a further sensor unit detects the environmental condition and outputs environmental status data to an evaluation unit for data fusion of the environmental data with the environmental status data for determining a coefficient of friction indication. A further sensor unit detects the vehicle state and outputs vehicle state data to an evaluation unit for data fusion of the vehicle state data with the friction coefficient indication and the driver service data for determining the driving state. In addition, the driver specifications are detected by a further sensor unit and driver service data are output to an evaluation unit for data fusion of the driver service data with the vehicle status data for determining the driver's driving course.

An advantageous development of the method according to the invention provides that the driving safety coordinator issues an optical, acoustic and / or haptic warning to the vehicle driver before the execution of an autonomous intervention to avoid it.

Another key idea is that the driving safety coordinator determines to predict operational safety and situational at least one permissible driving corridor and or optimal Bewegungsstrajektorie and limits the driver by means of actively controllable components on the driving corridor and the motor vehicle by means of actively activatable components in the driving corridor or on the movement trajectory.

The invention will be explained in more detail with reference to an embodiment in conjunction with the accompanying drawings. In the drawing shows:

1 a schematic representation of a vehicle with an environment sensor for detecting objects in the environment of the vehicle;

2 a schematic representation of a driver assistance system;

3 a block diagram of the safety device according to the invention and

4 a schematic representation of corridors that are suitable for evasion.

For the purposes of the present invention, "steering wheel" is representative of all conceivable man-machine interfaces that the driver can operate in the sense of steering and controlling the motor vehicle, such as switch inputs, a joystick or a touchpad as well as externally transmitted control commands ,

The terms signal quality and data quality are used largely synonymously.

The following is generally based on 1 and 2 a safety device for motor vehicles explained and based on the 3 and 4 an embodiment of the invention explained in more detail.

In 1 is an example of a four-wheeled, two-axle vehicle 1 represented, via an environment sensor 2 has, with the objects O can be detected in the vicinity of the vehicle, which are in particular other vehicles that are in the same or an adjacent lane sideways and / or in front of the vehicle 1 move. As objects O but also static or almost static objects such as trees, pedestrians or lane boundaries come into question. An example is an environment sensor 2 with a detection area 3 shown having a solid angle in front, beside or behind the vehicle 1 includes, in the example of an object O is shown. In the environment sensors 2 is for example a LIDAR sensor (Light Detection and Ranging) which is known per se to those skilled in the art. However, other environment sensors such as radar sensors or optical camera systems can also be used. In addition, the information about the environment can be determined by means of the so-called car-to-X communication. This refers to the transmission of environmental information from other vehicles or from other detection points to the vehicle 1 , The environment sensor 2 measures the distances d to the detected points of an object as well as the angles φ between the connecting straight lines to these points and the center longitudinal axis of the vehicle, as shown in FIG 1 is exemplified for a point P of the object O. The the vehicle 1 facing fronts of the detected objects are composed of several detected points to which the sensor signals are transmitted, which establishes correlations between points and the shape of an object and determines a reference point for the object O. For example, the center point of the object O or the center point of the detected points of the object can be selected as the reference point. The speeds of the detected points and thus the speed of the detected objects, in contrast to a radar sensor (Doppler effect) using the LIDAR environment sensor 2 can not be measured directly. They are calculated from the difference between the distances measured in successive time steps in a cyclically operating object recognition unit 21 calculated. Similarly, in principle, the acceleration of the objects can be determined by deriving their positions twice.

2 shows a schematic representation of a driver assistance system whose components, with the exception of sensors, actuators and other hardware are preferably designed as software modules that within the vehicle 1 be executed by means of a microprocessor. As in 2 shown, the object data in the form of electronic signals within the driver assistance system shown schematically to a decision device 22 transmitted. In the decision-making institution 22 will be in block 23 determined on the basis of the information about the object O an object trajectory. Furthermore, a movement trajectory of the vehicle 1 in block 24 based on information about the driving dynamics of the vehicle 1 determined with the help of other vehicle sensors 25 be determined. In particular, the vehicle speed, which can be determined, for example, with the aid of wheel speed sensors, the steering angle δ measured by means of a steering angle sensor, at the steerable wheels of the vehicle 1 , the yaw rate and / or the lateral acceleration of the vehicle 1 , which are measured by means of appropriate sensors, used. In addition, it is possible from the with the vehicle sensors 25 measured vehicle dynamic states of the vehicle to calculate or estimate model-based variables. An indication of the coefficient of friction between the tires of the vehicle 1 and the roadway is also obtained from the vehicle sensors or from the road condition. This friction coefficient indication is determined in particular by the brake control system. Then it will be in the decision maker 22 inside the block 26 Checks if the motor vehicle 1 is located on a collision course with one of the detected objects O. If such a collision course is detected and which is also in the decision-making 22 determined collision time, ie the time until the determined collision with the object O, falls below a certain value, is a trigger signal to a Bahnvorgabeeinrichtung 27 transmitted. The triggering signal results in that an escape path, ie a movement trajectory, is first calculated within the path specification device. Then, on the basis of the determined avoidance trajectory or movement trajectory, a starting point for the evasive maneuver is determined at which the evasive maneuver must be started in order to be able to just dodge the object O. These steps are preferably repeated in time steps until there is no danger of collision due to changes in the course of the object O or of the vehicle 1 exists more or until the vehicle 1 reached the starting point for an evasive maneuver. If so, parameters representing the escape lane or path are sent to a steering / brake actuator control 28 transmitted.

With the help of the environmental data of the environment sensor 2 it is recognized whether an intervention is necessary and useful. In addition, it is recognized how safe the environment sensors 2 can assess the situation and thus which signal quality the environment data have. The basic idea of the present invention is that, depending on the criticality of the driving situation and the signal quality of the surroundings data, a fallback recommendation to the vehicle driver or an evasion support for the driver or an autonomous intervention for evasion is carried out, a more dominant measure being taken Criticality of the driving situation and the better the signal quality of the environment data. Can be avoided without danger, because the environment sensors 2 has recognized the situation safely and accurately enough, an autonomous evasion process takes place. If the uncertainty and thus the danger in the case of an evasive action are too high, support for an evasive maneuver initiated by the driver takes place.

In 3 the schematic structure of the safety device according to the invention is shown. The idea is the networking of the various sensor units 2 . 20 . 30 . 40 , With the available data from the sensor units 2 . 20 . 30 . 40 a data fusion is performed. Data fusion is the combination and completion of incomplete data sets for data cleansing. In this case, several partially incomplete data sets must be combined with one another in order to increase the signal quality of the environment data and to obtain a complete picture of the environment. Before the data fusion of the data sets of two sensor units 2 . 20 . 30 . 40 possible, they must be brought together on a common data schema. This process is also called data schema integration. This data fusion makes it possible to obtain information about the environment of the motor vehicle 1 to win, which have a better signal quality and quality. A better signal quality or data quality stands for a more accurate and faster calculation of the risk of collision. As will be explained in more detail below, data fusion also takes place in order to obtain improved information on the environmental status, the vehicle status and the driver service data.

At least one sensor unit is used to detect the environmental conditions 2 , This so-called environment sensor 2 As already mentioned, it is formed from a radar, lidar or video camera system or from a combination of the systems mentioned. The with the help of at least one of these sensor unit 2 Information obtained with map information, GPS data and information obtained by means of car-to-X communication, within an evaluation unit 4 for the data fusion of the environment data in the sense of a data fusion combined. After the data fusion an evaluation of the improved environment data for recognition of objects O takes place. The position and movement of the object O is sent to a driving safety coordinator 6 transmitted. This driving safety coordinator 6 Based on physical driving limits and taking into account the surrounding data, it determines permissible driving corridors K1, K2, K3, Kn, thereby ensuring the operational safety of the vehicle 1 Predictive and situational, by the driving corridors K1, K2, K3, Kn are designed so that a combined braking / evasive maneuver or a braking maneuver is performed. The driving corridors K1, K2, K3, Kn are described below on the basis of 4 explained in more detail.

As 3 is further removed, at least one further sensor unit is used 20 the recording of the environmental condition.

This at least one sensor unit 20 for detecting the environmental condition is formed by a rain sensor, a thermocouple and / or by a camera system. Taking into account the tire characteristic of the vehicle tires used, a data fusion in the evaluation unit becomes from the determined environmental state data 24 performed and in the step 25 a friction value indication between tire and roadway is determined from the adjusted environmental condition data. This determination of the Reibwertindikation for example, based on the knowledge of the road condition. This determined Reibwertindikation is also to the driving safety coordinator 6 passed on.

Another at least one sensor unit 30 serves to detect a vehicle condition. This at least one sensor unit 30 for vehicle condition detection is formed of a wheel speed sensor, a lateral acceleration sensor, a longitudinal acceleration sensor or a yaw rate sensor. A combination of the mentioned sensors is also possible. The sensor unit 30 for vehicle condition detection is also called vehicle condition observer. In an evaluation unit assigned to this vehicle condition observer 34 the vehicle condition data are combined with the determined friction coefficient indication in the sense of a data fusion. This measure is in step 35 the vehicle condition is calculated and sent to the driving safety coordinator 6 output.

As 3 further disclosed is at least one further sensor unit 40 for detecting the driver specifications and for outputting driver service data. This at least one sensor unit 40 for detecting the driver specifications is formed by a steering angle sensor, a pedal angle sensor for the brake pedal and / or the accelerator pedal and / or by a giver of the direction indicator. The encoder of the direction indicator is colloquially referred to as a turn signal. The information includes whether the driver wants to turn left or right. The assigned evaluation unit 44 the newly determined vehicle state data are supplied and from these, together with the driver service data, a data fusion is performed. Since the data fusion effects a data cleansing by merging and completing incomplete data records, in the step 45 a precise driver's driving course is calculated and sent to the driving safety coordinator 6 output. The driving safety coordinator 6 the position and movement of the object O and the determined friction coefficient indication are transmitted. In addition, the driving safety coordinator receives 6 the vehicle condition and the driver's course. From these data, a permissible driving corridor K1, K2, K3, K4 to Kn is determined. To clarify the permissible driving corridors K1, K2, K3 shows 4 your own vehicle 1 and the object O in the direction of travel. The driving corridors K1, K3 shown in this example are determined situationally and predictively and are located within the predicted free-motion area on the left and right of the object O. The corridor K2 designates an area in front of the object O without an escape path when an emergency stop is sufficient to avoid a collision with the object O. That is, the driving safety coordinator 6 initiates emergency braking if the permissible driving corridors K1 and K3, Kn do not provide any possibility of avoidance in the event of a high risk of collision. In this case, the travel corridor K2 is provided as a braking distance.

To the vehicle 1 now in the permissible driving corridors K1, K2, K3 to keep Kn is determined by 3 explained in more detail how the driving safety coordinator 6 is working. As already mentioned, the driving safety coordinator 6 Position and movement of the object or objects O and the determined Reibwertindikation transmitted. In addition, the driving safety coordinator receives 6 the vehicle condition and the driver's course. From these data, a permissible driving corridor K1, K2, K3 to Kn is determined and a desired course calculation of the own vehicle 1 performed. To the vehicle 1 in the allowable corridor K1, K2, K3 to Kn, become active components 9 controlled such that the driver specification is limited to the available corridor K1, K2, K3 to Kn. These actively controllable components 9 Are located in the chassis, drive or in a human-machine interface, such as brake pedal, drive motor, steering, transmission, damper, stabilizer or direction indicator. Specifically, the driving safety coordinator controls 6 the actively controllable components 9 such that an opposing force is generated on the accelerator pedal or an engagement in the drive motor, an intervention in the drive train or a brake intervention is performed to keep the vehicle in the driving corridor K1, K2, K3 to Kn. Alternatively or additionally, the actively controllable components 9 triggered such that an additional steering torque and / or an additional steering angle or a wheel-individual braking intervention for generating a yawing moment is generated. This control is also suitable to keep the vehicle in the driving corridor K1, K2, K3 to Kn. In a particular embodiment, any action by the driver is overruled, so that the driver's power over his vehicle 1 reserves.

As 3 is further removed is rated by the driver safety coordinator 6 the determined data with regard to the criticality of the driving situation and possibly gives a warning to the driver and / or the environment. This environment warning 8th can be done visually, acoustically or with the help of a Car-to-X communication. By means of car-to-x communication, the environment warning can be provided 8th both to the infrastructure and to other vehicles. The warning to the driver takes place via a man-machine interface 7 , also called Human-Machine-Interface, HMI for short. The warning to the driver can be haptic, audible or visual. All controllable components of the human-machine interface are included 7 suitable, such as a counterforce on the accelerator pedal or a vibration of the steering wheel. Warning lights and audible warning tones are also suitable for issuing a warning to the driver.

The driving safety coordinator 6 Thus, the position and movement of the object O and the determined Reibwertindikation are transmitted. In addition, the driving safety coordinator receives 6 the vehicle condition and the driver's course. From these data, a permissible driving corridor or an optimal movement trajectory is determined. The determination of the driving corridor or the movement trajectory is situational and predictive. The driving corridor or the movement trajectory are located within the predicted free surface on the left and right of the object O over. To the vehicle 1 to hold in the allowable corridor or on the optimal motion trajectory become active components 9 controlled such that the driver specification is limited to the available driving corridors K1, K2, K3, Kn or the optimal movement trajectory. These actively controllable components 9 Are located in the chassis, drive or in a human-machine interface, such as brake pedal, drive motor, steering, transmission, damper, stabilizer or direction indicator. Specifically, the controls Driving safety coordinator 6 the actively controllable components 9 such that an opposing force is generated on the accelerator pedal or an engagement in the drive motor, an intervention in the drive train or a brake intervention is performed to keep the vehicle in the driving corridor or on the movement trajectory. Alternatively or additionally, the actively controllable components 9 triggered such that an additional steering torque and / or an additional steering angle or a wheel-individual braking intervention for generating a yawing moment is generated. This control is also suitable for keeping the vehicle in the driving corridor K1, K2, K3, Kn or on the movement trajectory. With a fallback and fallback assistance, any action is overruled by the driver, leaving the driver in control of his vehicle 1 reserves.

As already mentioned, the essential idea of the invention is that, depending on the criticality of the driving situation and the signal quality of the surrounding data, only an evasion recommendation to the vehicle driver or an evasion assistance for the driver is output or an autonomous intervention for evading is performed. A more dominant measure is taken, the higher the criticality of the driving situation and the better the signal quality of the surrounding data. In this context one speaks also of the stiffness of the avoidance function. The stiffness of the evasive function denotes dominance or dominance over the motor vehicle. The basic idea is based on the knowledge that the higher the criticality of the driving situation and the better the signal quality of the surrounding data, the higher the rigidity of the avoidance function. The driving safety coordinator 6 assumes the executive power over the motor vehicle, the higher the criticality of the driving situation and the better the signal quality or data quality of the surrounding data, the driving safety coordinator 6 an alternative support for the driver outputs when the signal quality of the environment data is low. The driving safety coordinator 6 gives a fallback recommendation to the driver and supports the avoidance if the signal quality of the environment data has a medium value. If the signal quality of the environment data is sufficiently good, the driving safety coordinator leads 6 an autonomous intervention to dodge through.

If the driver starts an evasive action before the evasive action responds, the driver is in any case assisted when the last possible braking point to bring the vehicle safely in front of the object O to bring to a halt (the so-called "Last Point to Brake") is already over. The last possible braking point (Last Point to Brake) is only supported if there would be an unstable driving dynamics situation without support.

The idea of the invention to select a more dominant measure from avoidance recommendation, alternative assistance and autonomous intervention as a function of the criticality of the driving situation and the signal quality of the surroundings data is explained in more detail below with reference to four examples:

Example 1:

About the environment sensor 2 it is recognized that an evasive action is necessary. However, the system determines that the evasive action can take place entirely within its own lane. Therefore, an automatic evasive maneuver is started, even without the driver has initiated this.

Example 2:

About the environment sensor 2 it is recognized that an evasive action is necessary. In addition, it is recognized that there are alternative areas that are free, such as road blocks, which are not supposed to be used. For the evasive action, these alternate areas are sufficient, which is why an automatic evasive maneuver is started, even without the driver initiating this.

Example 3:

About the environment sensor 2 it is recognized that an evasive action is necessary. However, this must be avoided on the adjacent lane. About additional environment sensor 2 it is recognized that this strip is free and does not approach any vehicle from behind. Since it is a highway and thus can not be expected with oncoming traffic, an automatic evasive maneuver is started, even without the driver has initiated this.

Example 4:

About the environment sensor 2 it is recognized that an evasive action is necessary. However, this must be avoided on the adjacent lane. It is a highway, which is recognized for example by electronic map material, which is why one can not expect oncoming traffic. However, there is no environment sensor 2 is present, which can detect whether approaching from behind a vehicle is not avoided autonomously, but only warned. If the driver initiates the evasive maneuver, the function supports him.

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

• EP 1735187 A1 [0002]

Claims (8)

Method for the safe operation of a motor vehicle ( 1 ) with at least one sensor unit ( 2 ) for detecting the environmental conditions and for the output of environmental data, an evaluation unit ( 4 ) for evaluating the environmental data and an evaluation unit ( 5 ) for recognizing free spaces and objects (O), their position and movement, as well as with a driving safety coordinator ( 6 ), the risk of collision of the motor vehicle ( 1 ) determined with an object (O) on the basis of a risk assessment, characterized in that the driving safety coordinator ( 6 ), based on the criticality of the driving situation and the signal quality of the surroundings data, issues an evasive recommendation to the vehicle driver or an evasion assistance for the vehicle driver or carries out an autonomous evasion intervention, wherein the driving safety coordinator ( 6 ) takes a more dominant measure, the higher the criticality of the driving situation and the better the signal quality of the environmental data. A method according to claim 1, characterized in that the driving safety coordinator ( 6 ) assumes the exercising power over the motor vehicle, the higher the criticality of the driving situation and the better the signal quality of the surrounding data, whereby the driving safety coordinator ( 6 ) - an evasion support for the driver outputs when the signal quality of the environment data is low, - gives a fallback recommendation to the driver and supports the dodge, if the signal quality of the surrounding data has a medium value and - performs an autonomous intervention to dodge when the signal quality the environment data is sufficiently good. A method according to claim 1 or 2, characterized in that the signal quality of the environment data is improved by means of a data fusion of further data. Method according to claim 3, characterized in that a further sensor unit ( 20 ) records the environmental condition and sends environmental status data to an evaluation unit ( 24 ) for data fusion of the environmental data with the environmental status data for determining a coefficient of friction indication. Method according to claim 4, characterized in that a further sensor unit ( 30 ) detects the vehicle condition and vehicle status data to an evaluation unit ( 34 ) for data fusion of the vehicle condition data with the coefficient of friction indication and the driver provisioning data for determining the driving condition. Method according to claim 4, characterized in that a further sensor unit ( 40 ) the driver specifications are entered and driver information is sent to an evaluation unit ( 44 ) for data merging the driver service data with the vehicle condition data for determining the driver's fare. Method according to Claim 1 or 2, characterized in that the driving safety coordinator ( 6 ) emits an optical, audible and / or haptic warning to the driver before performing an autonomous intervention to dodge. Method according to one of the preceding claims, characterized in that the driving safety coordinator ( 6 ) to ensure operational safety, predictively and situationally determined at least one permissible driving corridor (K1 to Kn) and / or an optimal movement trajectory and the driver specification by means of actively controllable components ( 9 ) is limited to the driving corridor and the motor vehicle ( 1 ) by means of the actively controllable components ( 9 ) stops in the driving corridor (K1 to Kn) or on the movement trajectory.

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