WO2020038535A1

WO2020038535A1 - Method for determining accident-relevant parameters using a radar system of a vehicle

Info

Publication number: WO2020038535A1
Application number: PCT/DE2019/200027
Authority: WO
Inventors: Alexander Kamann; Andreas Koch; Thomas Brandmeier; Frank Gruson; Patrick Held; Andreas Forster
Original assignee: Conti Temic Microelectronic Gmbh; Continental Automotive Gmbh
Priority date: 2018-08-24
Filing date: 2019-04-02
Publication date: 2020-02-27
Also published as: DE102018214338A1

Abstract

The invention relates to a method for determining accident-relevant parameters in the surroundings of a vehicle (1), having the following steps: - detecting information in the surroundings of the vehicle (1) using at least one radar sensor (2) of the vehicle (1), wherein the radar sensor (2) has a first detection mode with a first radar cycle duration (S10); - at least temporarily detecting accident-relevant surroundings information using the at least one radar sensor (2) of the vehicle (1), said accident-relevant surroundings information being detected using a second detection mode with a second radar cycle duration which is shorter than the first radar cycle duration (S11); - analyzing the accident-relevant surroundings information detected in the second detection mode in order to ascertain accident-relevant parameters (S12); and - ascertaining information for activating at least one safety system on the basis of the accident-relevant parameters (S13).

Description

The invention relates to a method and a radar system for determining accident-relevant parameters as well as a vehicle with such a radar system.

It is known from the prior art to activate a safety system of a vehicle, for example an airbag or a belt tensioner, in the event of a collision with a collision object or a skid situation.

Radar sensors in vehicles for the detection of

Environmental information captures raw radar information and processes it in radar cycles to environmental information, which can be displayed on a radar map, for example. Depending on the sensor, the radar cycles have, for example, a radar cycle duration in the range between 20 ms and 100 ms, i.e. the processes are repeated periodically after a radar cycle time has elapsed.

With regard to the activation of safety systems, in particular passive safety systems such as airbags or belt tensioners, it is advantageous if the parameters relevant to the accident, for example overlap between the ego vehicle and the collision object, impact angle and / or speed vector of the collision object can be determined as precisely as possible. Since these accident-relevant parameters can change very strongly, especially immediately before a collision, for example due to a strong steering maneuver or a

Skid situation, the previously mentioned radar cycle times are too long in order to be able to predict the parameters relevant to the accident with sufficient accuracy.

Proceeding from this, it is an object of the invention to provide a method for determining parameters relevant to accidents, by means of which, based on at least one radar sensor,

accident-relevant environmental information, a sufficiently precise determination of accident-relevant parameters and based on this a situation-appropriate activation of one or more

Security systems is possible.

The task is accomplished through a process with the characteristics of

independent claim 1 solved. Preferred embodiments are the subject of the dependent claims. A radar system is the subject of the independent claim 14 and a vehicle with such a radar system is the subject of claim 15.

According to a first aspect, the invention relates to a method for determining parameters relevant to accidents. The process comprises the following steps:

First, information in the area surrounding the vehicle is acquired by means of at least one radar sensor of the vehicle. The radar sensor is operated in a first detection mode with a first radar cycle duration. This first acquisition mode is, for example, a standard acquisition mode in which environmental information is acquired in a first acquisition area.

At least occasionally, accident-relevant environmental information is acquired using the at least one radar sensor of the vehicle, specifically using a second acquisition mode using a second Radar cycle duration that is shorter than the first radar cycle duration. The second detection mode can be activated, for example, depending on the situation, for example when an accident or skid situation that is most likely to occur has been detected. The first acquisition mode can either continue to be executed in parallel or the first acquisition mode can pause. Alternatively, the second detection mode can be operated continuously in parallel with the first detection mode. The second detection mode can have a second one that is restricted compared to the first detection area

Have detection area.

The accident-relevant recorded in the second recording mode

Environmental information is then evaluated to determine accident-relevant parameters. This evaluation can take place, for example, by determining which one is used

Coverage between the ego vehicle (ie the vehicle that carries the radar sensor) and a collision object (ie the object with which the ego vehicle collides) a collision occurs, which angle of impact exists between the ego vehicle and the collision object or how high the relative speed between Ego vehicle and collision object is.

Finally, information on activating at least one

Safety system determined based on the accident-relevant parameters and possibly activated one or more safety systems depending on it.

The main advantage of the method according to the invention is that the second detection mode with a shorter radar cycle duration compared to the first detection mode enables a more precise detection of the accident-relevant environmental information, especially immediately before the collision. Immediately in this time range Before a collision, the movement of the ego vehicle or the collision object often changes very strongly, so that a prediction of

Accident-relevant parameters based on information that is determined in the first detection mode is only possible with imprecision, but with a higher update rate due to the shorter radar cycles in the second detection mode.

According to one exemplary embodiment, in the second detection mode a detection of raw radar information that is different from the first detection mode and / or a changed signal processing of the detected radar information is carried out. In particular, the acquisition of raw radar information is reduced in complexity (for example by restricting the detection range,

Shutdown of transmit / receive channels etc.) and the

Signal processing simplified, for example by restricting the speed range and / or the speed resolution in which the recorded Doppler information is evaluated, or by reducing it to one or some objects with which a collision is likely to occur. This can, despite shortening the

Radar cycle duration a sufficiently precise determination of the

accident-relevant environmental information.

According to one embodiment, the detection of

accident-relevant environmental information in a restricted detection area, which is limited compared to the detection area that is detected in the first detection mode. The detection range can be restricted by restricting the detected azimuth range, elevation range and / or by reducing the detection radius (for example to a detection radius smaller than a distance threshold value, for example 20 m). This allows the raw radar information to be processed with the same processing power processing computer unit, despite the shorter radar cycle, a sufficiently precise recording of the accident-relevant

Environmental information is provided. According to one exemplary embodiment, in the first detection mode of the radar sensor or by further sensors of the vehicle, containment information is used to limit the detection of accident-relevant environmental information in the second detection mode. For example, the radar sensor in the first

Detection mode detected a collision object with which a collision could occur. This object can have a certain speed, for example. Based on this information, for example, the detection area in the second detection mode can be restricted to the area in which the

Collision object is located. In addition, the Doppler information in the second acquisition mode can only be evaluated in an area that lies around the speed of the collision object. In addition to the collision object, other objects detected can be excluded from object tracking. Further narrowing of the recording are also conceivable. As a result, the acquisition can be focused on the relevant area in the second acquisition mode.

However, the narrowing cannot only be based on the first

Detection mode of the radar sensor recorded restriction information but also, for example, based on information that is provided by further sensors of the vehicle, for example a camera, ultrasound sensor system, a LIDAR sensor, etc., by third-party vehicles in the vicinity of the ego vehicle and / or by a stationary one , Infrastructure equipped with sensors for recording safety-relevant information, which is arranged, for example, to the side of a road, are provided. According to one exemplary embodiment, the detection range is limited, in the detected angular range and / or in the recorded speed information range and / or by restricting the transmit / receive channels of the radar sensor. This allows the

Complexity of acquisition can be significantly reduced.

According to one exemplary embodiment, the second detection mode is based on information that was determined by the radar sensor in the first detection mode, by information provided by a further sensor, by a third-party vehicle

Provided information is activated by information provided by a stationary infrastructure and / or by information from a card that contains security-relevant information. The second acquisition mode can thus be triggered selectively. The first

Acquisition mode can then be interrupted at least temporarily or can be carried out parallel to the second acquisition mode.

According to one exemplary embodiment, an accident situation with at least one collision object is detected in the first detection mode of the radar sensor. Based on this detection of the collision object, the detection of accident-relevant environmental information is limited in the second detection mode to the local area in which the at least one detected collision object is located. This in turn can significantly reduce the complexity of the acquisition.

According to one exemplary embodiment, raw radar information or information derived therefrom is used at least temporarily in the second detection mode, and this is used in the second detection mode to determine accident-relevant environmental information in comparison to the first Detection mode subjected to changed signal processing. In other words, in the second detection mode, at least at times there is no separate transmission of radar signals and reception of reflected portions of these radar signals, but rather in the second

Acquisition mode will be raw radar information or so

derived information of the first detection mode used to the accident-relevant environmental information by a suitable

To determine signal processing. According to one exemplary embodiment, raw radar information adapted to a possibly occurring accident situation is acquired in the second detection mode, at least temporarily, in pauses in the first detection mode, in which no raw radar information for the first detection mode is acquired. This raw radar information is subjected to signal processing in order to determine accident-relevant environmental information. Here, "acquisition of raw radar information adapted to a possibly occurring accident situation" means that the transmission of radar signals and

Receiving reflected portions of these radar signals in the second detection mode can be different from the first detection mode, for example because the detection range is restricted.

According to one exemplary embodiment, the second radar cycle duration is adapted as a function of the distance to a detected collision object. Preferably, the second radar cycle duration can be increasingly shortened depending on the distance between the ego vehicle and the collision object in order to change the possible

Accident-relevant parameters just before the collision can also be recorded more precisely, the detection area or others Acquisition parameters can be adapted adaptively in the second acquisition mode.

According to one embodiment, the accident-relevant

Ambient information is acquired through the interaction of several sensors. For example, the information recorded by a plurality of sensors, in particular radar sensors, is processed centrally to form a radar image, so that

environmental information relevant to the accident can be determined. In the sensor network, for example, those radar sensors can be operated in the second detection mode with which accident-relevant environmental information relating to one or more collision objects can be detected. According to one exemplary embodiment, the sensors that are detected by several sensors, in particular radar sensors, are brought together

Information and the evaluation of the accident-relevant environmental information recorded in the second detection mode on a

Computing unit of a sensor, in particular a radar sensor, or on a central computing unit remote from the sensors. The central processing unit can be used exclusively for processing and evaluating the accident-relevant environmental information recorded in the second detection mode and, for example, also determining information for activating vehicle safety systems, or the central processing unit can also perform other processing tasks in addition to this task.

According to one exemplary embodiment, the accident-relevant environmental information is provided in the second detection mode by providing raw radar information from the individual radar sensors and a fusion of the raw radar information for further signal processing a computing unit of a sensor, in particular a radar sensor, or obtained in a central computing unit remote from the sensors. In other words, not only the downstream one

Signal processing takes place centrally, but the raw radar information provided by the individual radar sensors can already be combined centrally in order to derive the accident-relevant information

Get environmental information.

According to one embodiment, based on the

Information on the activation of at least one security system, a selective selection of one or more security systems of the vehicle or a selective adaptation of functional features of at least one security system. Depending on the situation, it can be decided, for example, which airbags (front, side, knee airbags etc.) must be activated, whether or to what extent the belt tensioners are to be activated, at which point in time one or more safety systems are activated, etc. even before the actual collision. According to a further aspect, the invention relates to a radar system for a vehicle. The radar system includes:

- At least one radar sensor used to detect

Information is formed in the surrounding area of the vehicle, wherein the radar sensor has a first detection mode with a first radar cycle duration;

a computer unit which is designed to record accident-relevant environmental information, the accident-relevant environmental information being recorded by means of a second detection mode of the radar sensor with a second radar cycle duration which is shorter than the first

Radar cycle time; - A computer unit that is used to evaluate the second

Acquisition mode captured accident-relevant

Environmental information for determining accident-relevant parameters is formed; and

- A computing unit, which is used to determine information about

Activation of at least one safety system is designed based on the accident-relevant parameters.

The aforementioned computer units can be done by a single

Computer unit can be implemented or at least partially different computer units can be provided, by means of which

the aforementioned steps are carried out.

Finally, the invention comprises a vehicle with a radar system as described above.

“Collision object” in the sense of the present invention is understood to mean any stationary or moving object that collides with the ego vehicle with a certain probability.

“Accident-relevant parameters” in the sense of the present invention are understood to mean any parameters that characterize a collision or a collision. This can especially the

Overlap between the collision object and the ego vehicle, the angle of impact, speed information (e.g. the

Relative speed between the collision object and the ego vehicle), the opposing target mass and / or the opposing vehicle type (truck, van, car, possibly small car, SUV etc.). “Radar cycle” in the sense of the present invention is a regularly or irregularly repeating acquisition and Understand the evaluation process in which radar signals are sent and reflected portions of these radar signals (raw radar information) are then received. In addition, signal processing of the received raw radar information can take place in the radar cycle and an environment model can be generated if necessary.

“Radar cycle time” in the sense of the present invention means the time period with which the radar cycle repeats itself. “Raw radar information” in the sense of the present invention means the reflected portions of the radar signals that are received at the radar sensor.

“Signal processing” in the sense of the present invention includes an analog-digital conversion of the raw radar information and one

Further processing of the analog-to-digital converted signals understood by a digital signal processing unit.

“Restriction information” in the sense of the present invention means any information by means of which one

It is possible to limit the detection to an area that is interesting in relation to a collision situation. This can be, for example

Be location information, which indicates in which area one

Collision object is located. Furthermore, containment information can provide an indication of a specific collision object. In addition, narrowing information can also affect one

Information relating to the collision object, for example

Speed information, directional information etc. “Accident situation” or “accident scenario” in the sense of the present invention means both situations in which a collision occurs occurs with a collision object, as well as situations in which the vehicle is in a safety-critical driving situation,

for example a skid situation. For the purposes of the invention, the terms “approximately”, “essentially” or “approximately” mean deviations from the respectively exact value by +/- 10%, preferably by +/- 5% and / or deviations in the form of changes which are insignificant for the function , Further developments, advantages and possible uses of the invention also result from the following description of

Embodiments and from the figures. Everyone is there

described and / or illustrated features for themselves or in any combination basically the subject of the invention, regardless of their summary in the claims or their relationship. The content of the claims is also made part of the description.

The invention is described below with reference to the figures

Exemplary embodiments explained in more detail. Show it:

Fig. 1 exemplarily and schematically a vehicle with a

Radar sensor with a detection area in which a

Collision object occurs;

Fig. 2 shows an example of a schematic diagram that the

Process steps for determining accident-relevant

Parameters and for triggering a safety system based on these accident-relevant parameters

illustrated; Fig. 3 exemplary and schematic of a vehicle with a

Radar sensor with a limited detection area, a collision object moving towards the vehicle; 4 shows an example of a schematic diagram which illustrates radar cycles of a first detection mode in comparison with radar cycles of a second detection mode; and

5 shows, by way of example and schematically, a vehicle with a large number of sensors, in particular radar sensors, which are designed to work in a sensor network.

FIG. 1 shows, by way of example and schematically, a detection area EB of a radar sensor 2 of a vehicle 1. This detection area EB is, for example, a standard detection area that is used in a first detection mode in order to detect environmental information around the vehicle 1. The first detection mode is used in particular in normal driving situations with little or no risk of collision. In the first acquisition mode, the

Radar sensor 2 operated with a radar cycle that a first

Has radar cycle duration. This first radar cycle duration is typically greater than 20 ms, for example in the range between 50 ms and 100 ms. In such a radar cycle, raw radar information is both acquired, for example by transmitting one or more radar signals and receiving reflected portions thereof

Radar signals, as well as the signal processing of this raw radar information into environmental information, which can be represented, for example, as a radar image in a radar map. Such a radar cycle can also include the generation of an environment model.

Several such radar cycles follow one another in time, in order to thereby implement a current environmental detection or from the time changes to draw conclusions about the surrounding situation.

2 schematically shows steps of a method for recording accident-relevant parameters and their use for activating at least one safety system of a vehicle.

In a first step, as previously described,

Surrounding area information is acquired in a first acquisition mode with a first radar cycle duration (S10).

In order to be able to predict accident parameters as precisely as possible shortly before an collision occurs, accident-relevant ones can be used

Ambient information is acquired using a second acquisition mode that uses a radar cycle with a second radar cycle duration that is shorter than the first radar cycle duration. The second radar cycle duration is preferably <20 ms (S11).

The through the second acquisition mode with the shorter one

Radar cycle duration recorded accident-relevant environmental information can then be evaluated to determine accident-relevant parameters (S12). These can include, for example, the overlap of one's own vehicle 1 with the collision object, the impact angle,

Speed information etc. By the shorter one

Radar cycle duration, the accident-relevant parameters can be determined with greater accuracy.

Based on the accident-relevant parameters, one or more safety systems of vehicle 1 can then be activated (S13), so that the shorter radar cycle duration in the second detection mode enables more specific activation of the safety systems. The acquisition of environmental information in the second

Acquisition mode can take place at least temporarily parallel to the acquisition in the first acquisition mode or instead of the acquisition in the second acquisition mode. For example, the following scenarios are possible:

The second detection mode can sometimes run parallel to the first detection mode. The second acquisition mode is started, for example, when one with a certain

Probability of an accident occurring was recognized. In the second detection mode (with the second radar cycle duration), for example, accident-relevant environmental information is provided at least temporarily in parallel with environmental information that results from the first detection mode (with the first radar cycle duration).

Alternatively, the second acquisition mode can be used instead of the first

Acquisition mode, i.e. it will only

environmental information relevant to the accident with the second

Radar cycle duration provided and detection in the first

Acquisition mode paused.

Furthermore, as an alternative, the second detection mode can always be carried out parallel to the first detection mode, for example in such a way that a continuously compared to the first detection mode

restricted surrounding area or only one or more objects can be detected by the second detection mode.

FIG. 3 shows an example of a situation shortly before a collision of the vehicle 1 with a collision object KO, in the shown

Embodiment also a vehicle. As from comparing the 1 and 3, the detection area in FIG. 3 has been reduced to a restricted detection area EB 'in order to thereby specifically detect the surrounding area in the area of the collision object KO. This restriction of the detection area EB 'enables the accident-relevant ones to be used despite the shorter radar cycle times

Collect environmental information.

In addition to changing the detection area, the

Signal processing or the processing of raw radar information can be suitably adapted so that signal processing can still be carried out despite shorter radar cycle times. This can

for example, by simply selecting radar ramps in succession during signal processing. First of all, it is possible for information about the accident scenario that is likely to occur to be transmitted to the radar sensor 2 or a control device assigned to it in the second detection mode. This information can be provided by the radar sensor 2 itself or another sensor, for example a further radar sensor of the vehicle 1, for example at least one camera, at least one

Ultrasonic sensor or at least a "light detection and ranging" (LIDAR) sensor. For example

collision object-related information (e.g. a tracked object with one or more object parameters), a local area (e.g.

Distance range and angular range in azimuth) for the second

Acquisition mode to be passed based on this

To be able to specifically record information that is relevant to the accident. In other words, environmental information that was recorded with the radar sensor 2 itself or at least one further sensor thus turns into hypothetical areas in which an accident can occur or hypothetical objects with which an accident occurs can be passed on to the second acquisition mode so that it can determine more precise, accident-relevant environmental information in this hypothetical area or on this hypothetical object.

To further reduce the computing complexity and thus accelerate signal processing, the range of the

restricted detection area EB ’to the immediate

Vehicle environment can be reduced, for example to one

Distance range smaller than a distance threshold,

for example <20m.

In addition, the complexity of the detection of the speed at which a collision object KO moves toward the vehicle 1 can be reduced by only selectively providing information about the vehicle

Speed determination can be used, for example those that are necessary for determining the speed range in which the speed of the collision object KO lies. Furthermore, it is possible to change the number of send and / or

To reduce reception channels of the radar sensor 2 in order to thereby slim down or accelerate the signal processing.

The algorithms for signal processing (e.g. object formation,

Object tracking etc.) and / or for determining or estimating parameters relevant to accidents are only applied to those radar information items that relate to the restricted detection range or speed range and / or are assigned to the collision object KO. FIG. 4 shows an example of a comparison of radar cycles in a first detection mode (upper table part) and in a second detection mode (lower table part, referred to as the 2nd EM)

Radar sensor 2. As with the arrow marked "t"

indicated, the radar cycles of the first acquisition mode and the second acquisition mode run in succession. The radar cycles of the first detection mode can, however, at least temporarily overlap with the radar cycles of the second detection mode. For the first acquisition mode, only two radar cycles (cycle I and cycle II) are outlined, which can each have several data acquisition phases (data acquisition I, data acquisition II). There can be pauses in one radar cycle between two data acquisition phases (empty fields between data acquisition I and data acquisition II), i.e.

Time phases in which there is no transmission of radar signals or reception of reflected portions of these radar signals. The one

Radar cycle recorded raw radar information (e.g. reflected

Signal strength, phase relationships etc.) are then in the respective

Radar cycle subjected to signal processing to

Get environmental information. There can also be one

Generation of an environment model per radar cycle.

For the second acquisition mode, seven radar cycles are shown as examples. As illustrated by the smaller field width compared to the field width of the radar cycles in the first detection mode, the radar cycle of the second detection mode has a smaller one

Radar cycle time on as the first acquisition mode.

The time assignment of the radar cycles in the second acquisition mode (each with a data acquisition phase (abbreviated in the figure

"Data acquisition") and a data processing phase (abbreviated in the figure "Data ver.")) For the data acquisition phases in the first acquisition mode are indicated by way of example and schematically by arrows. For example, the data acquisition in the radar cycles i and i + 1 in the second radar cycle takes place at least partially in parallel with the time

Data acquisition phase I in cycle I of the first acquisition mode.

Part of the raw radar information or radar information derived therefrom and partially processed from the data acquisition phase of the first acquisition mode is preferably also used in the second acquisition mode. For example, on a

Collision object or a suspected collision area as tailored information from the first acquisition mode

Information to be processed (as input information for data acquisition) is used in the second acquisition mode and is further processed via the signal processing carried out there to provide more up-to-date, accident-relevant environmental information.

This is especially true if the first and second

Acquisition mode are carried out at least temporarily in parallel.

This means that resource-efficient use of raw

Radar information or derived therefrom, partially signal-processed radar information.

Preferably there is a break in between

Data acquisition phases of the first acquisition mode (for example illustrated by the free field between data acquisition I and data acquisition II in FIG. 4), an acquisition from the second

Acquisition mode customized pipe radar information. In this way, time-critical, accident-relevant environmental information can also be determined during the pauses in the first recording mode. Here, as explained above, a collision object to be detected or the Surrounding area in which the collision is likely to occur, tailored detection (detected distance range, angular range, speed range, etc.). In the event that the second acquisition mode is carried out instead of the first acquisition mode, the data acquisition can always be tailored specifically to the second acquisition mode.

The second radar cycle duration of the second detection mode can be a constant, i.e. the second radar cycle duration is not changed depending on the situation. Alternatively, the second radar cycle duration

depending on the situation, i.e. Depending on the detected collision situation (ego vehicle drives to a stationary collision object, ego vehicle collides with a moving collision object, skid situation) or the relative speed of the ego vehicle to the collision object, the second radar cycle duration can be selected appropriately.

Furthermore, the second radar cycle duration can be changed depending on the distance to the collision object. In particular, the second radar cycle duration can be reduced with a decreasing distance from the collision object in order to be able to determine the parameters relevant to the accident even more precisely.

It is particularly advantageous if, as shown in FIG. 5, a plurality of radar sensors 2 are provided on the vehicle 1, at least

have different detection areas in sections and can at least partially work in the second detection mode in addition to the first detection mode. As a result, accident-relevant environmental information can be acquired not only by a single radar sensor 2 but also by a group of radar sensors and possibly other sensors (for example ultrasound sensors, cameras, LIDAR sensors) etc. These radar sensors 2 and possibly other sensors work

preferably in a sensor network in order to provide more comprehensive, accident-relevant environmental information. Depending on the local position of the collision object relative to the vehicle 1, those radar sensors 2 that are relevant to the accident can

Detect the surrounding area around the collision object KO, the second detection mode can be activated in order to determine the accident-relevant environmental information from the raw radar information generated by the combination of radar sensors 2, in which the second

Acquisition mode is enabled to be provided. The

Signal processing and determination of accident-relevant parameters for activating at least one safety system can take place either on a central computing unit, which is set apart from the radar sensors 2, or on a computing unit of a radar sensor 2 functioning as a master computing unit.

The invention has been described above using exemplary embodiments

described. It is understood that numerous changes as well

Modifications are possible without this being caused by the

Defined protection area is left.

LIST OF REFERENCE NUMBERS

1 vehicle

2 radar sensor

EB detection area

EB ’restricted detection area KO collision object

Claims

claims

1) Procedure for determining accident relevant parameters in the

Surrounding area of a vehicle (1), comprising the following steps:

- Acquisition of information in the area surrounding the

Vehicle (1) by means of at least one radar sensor (2) of the vehicle (1), the radar sensor (2) having a first detection mode with a first radar cycle duration (S10);

- At least temporarily recording accident-relevant

Environmental information by means of the at least one radar sensor (2) of the vehicle (1), the environmental information relevant to the accident using a second

Acquisition mode with a second radar cycle duration that is shorter than the first radar cycle duration (S11);

- Evaluate those recorded in the second acquisition mode

accident-relevant environmental information for determining accident-relevant parameters (S12); and

- Determining information for activating at least one

Safety system based on the parameters relevant to the accident (S13).

2) Method according to claim 1, characterized in that in

second acquisition mode one versus the first

Acquisition mode changed acquisition of raw radar information and / or a changed signal processing of the acquired

Radar information can be carried out. 3) Method according to claim 1 or 2, characterized in that the detection of accident-relevant environmental information in one restricted detection area (EB ') takes place, which is limited in comparison to the detection area (EB), which is detected in the first detection mode. 4) Method according to one of the preceding claims, characterized

characterized in that in the first detection mode of the radar sensor (2) or detected by further sensors of the vehicle

Delimitation information for delimiting the recording of accident-relevant environmental information in the second

Acquisition mode can be used.

5) Method according to claim 4, characterized in that a

Limitation in the detection range, in the detected angular range and / or in the detected speed information range and / or by restricting the transmit / receive channels of the radar sensor.

6) Method according to one of the preceding claims, characterized

characterized in that the second acquisition mode based on information in the first acquisition mode by the

Radar sensor (2) were determined, is activated by information provided by a further sensor, by information provided by a third-party vehicle, by information provided by a stationary infrastructure and / or by information from a card that contains safety-relevant information.

7) Method according to one of the preceding claims, characterized

characterized in that an accident situation with at least one collision object (KO) is detected in the first detection mode of the radar sensor (2) and a limitation of the detection of accident-relevant environmental information to the local area of the at least one detected collision object (KO).

8) Method according to one of the preceding claims, characterized

characterized in that in the second acquisition mode at least temporarily on raw radar information acquired in the first acquisition mode or information derived therefrom

is used and this to determine accident-relevant environmental information compared to the first

Detection mode undergo changed signal processing.

9) Method according to one of the preceding claims, characterized

characterized in that in the second detection mode, at least occasionally, during a pause in the first detection mode, in which no raw radar information for the first detection mode is detected, of an accident situation that may occur

adapted raw radar information is recorded and this is subjected to signal processing in order to determine accident-relevant parameters.

10) Method according to one of the preceding claims, characterized

characterized in that the second radar cycle time depending on the distance to a detected collision object (KO), in

Dependence on the relative speed between the ego

Vehicle and the collision object (KO) and / or depending on the relative acceleration between the ego vehicle and the collision object (KO) is adjusted. 11) Method according to one of the preceding claims, characterized

marked that the accident-relevant environmental information by interaction of several sensors, in particular

Radar sensors (2) are detected.

12) Method according to claim 11, characterized in that the

Merging the through multiple sensors, in particular

Radar sensors (2), recorded information and the evaluation of the accident-relevant recorded in the second detection mode

Environmental information is provided on a computing unit of a sensor, in particular a radar sensor (2), or on a central computing unit which is remote from the sensors.

13) Method according to claim 11 or 12, characterized in that in the second detection mode, the accident-relevant

Environment information by providing raw radar information from the individual radar sensors (2) and a fusion of the raw radar information for further signal processing in a computing unit of a sensor, in particular one

Radar sensor (2) or in a central processing unit remote from the sensors.

14) Method according to one of the preceding claims, characterized

characterized in that, based on the information for activating at least one security system, one or more security systems of the vehicle (1) are selected or functional features of at least one security system are selectively adjusted.

15) Radar system for a vehicle (1) comprising:

- At least one radar sensor (2) which is used to detect

Information in the area surrounding the vehicle (1) by means of is formed, the radar sensor (2) having a first detection mode with a first radar cycle duration;

- a computer unit, which is designed to acquire accident-relevant environmental information, the accident-relevant environmental information being acquired by means of a second acquisition mode of the radar sensor (2) with a second radar cycle duration that is shorter than the first radar cycle duration;

- A computer unit that is used to evaluate the second

Acquisition mode captured accident-relevant

a computer unit which is designed to determine information for activating at least one safety system based on the accident-relevant parameters.

16) Vehicle comprising a radar system according to claim 15.