DE102018108912A1 - Method and driver assistance system for the autonomous and driver-independent operation of a motor vehicle - Google Patents

Abstract

The invention relates to a method for the autonomous and driver-independent operation of a motor vehicle (4) equipped with an electrically controllable steering device (18), comprising at least the following steps: detecting environment data relating to the motor vehicle environment, and then determining one of the current position of the motor vehicle (4 ) and at least on the basis of environmental data, and then autonomously guiding the motor vehicle (4) along a first trajectory (14) of passable trajectories, which are located inside the safe driving lane (8). The invention provides that during the autonomous guidance of the motor vehicle (4) along the first trajectory (14) a check is made as to whether there is a risk of tipping over for the motor vehicle (4) with respect to a longitudinal axis of the motor vehicle (4), and if the result of this check is that there is no risk of tipping over for the motor vehicle (4), then the motor vehicle (4) is autonomously continued along the first trajectory (14), but if the result of this check is that a tipping over risk for the motor vehicle ( 4), then, by means of the electrically controllable steering device (18), steering intervention is autonomous and driver-independent in such a way that the motor vehicle now travels along a second trajectory (14) different from the first trajectory (14) instead of continuing along the first trajectory (14) ) is guided by passable trajectories within the safely passable driving tube (8), wherein the second trajectory (26) is distinguished by the fact that when the motor vehicle (4) is guided along the second trajectory (26), a lesser risk of tipping or no risk of overturning is to be expected or exists for the motor vehicle (4).

Description

The invention relates to a method for the autonomous and driver-independent operation of a motor vehicle equipped with an electrically controllable steering device, with at least one electrically controllable braking device and with an electrically controllable drive device, comprising at least the following steps: detecting environmental data relating to the motor vehicle and the motor vehicle environment; and then determining a driving route starting from the current position of the motor vehicle and safely traversable by the motor vehicle with respect to a collision with obstacles at least on the basis of the surroundings data, and then autonomously guiding the motor vehicle along a first trajectory of passable trajectories which are within the safely passable driving tube, according to the preamble of claim 1.

The invention also relates to a vehicle which is operated according to such a method, according to claim 18.

The invention further relates to a driver assistance system, which operates a motor vehicle autonomously and driver-independently, with an electrically controllable steering device comprising at least one electrically controllable braking device and with an electrically controllable drive device further comprising at least the following: At least one sensor device, which relates the motor vehicle ego data and the Detected surrounding environment data, electronic means which cooperate with the sensor device and are designed so that they determine a starting from the current position of the motor vehicle and safe in terms of a collision with obstacles by the motor vehicle passable driving tube based at least on the environment data and which autonomously guide the motor vehicle along a first trajectory of drivable trajectories, which are located within the safely passable driving tube, according to the preamble of claim. 9

The invention also relates to a motor vehicle having such a driver assistance system, according to claim 17.

Such a method and such a driver assistance system are known from the prior art.

The object of the present invention is to further develop a method and a driver assistance system of the type described above in such a way that critical driving dynamics situations can be avoided.

Furthermore, a motor vehicle with such a driver assistance system as well as a vehicle, which is operated according to such a method to be made available.

This object is solved by the features of claims 1, 9, 17 and 18.

Disclosure of the invention

1. a) Erfassen von das Kraftfahrzeug betreffenden Egodaten und das Kraftfahrzeugumfeld betreffenden Umfelddaten, und dann
2. b) Ermitteln eines von der momentanen Position des Kraftfahrzeugs ausgehenden und im Hinblick auf eine Kollision mit Hindernissen durch das Kraftfahrzeug gefahrlos befahrbaren Fahrschlauchs wenigstens auf der Basis der Umfelddaten, und dann
3. c) autonomes Führen des Kraftfahrzeugs entlang einer ersten Trajektorie von befahrbaren Trajektorien, welche sich innerhalb des gefahrlos befahrbaren Fahrschlauchs befinden.

The invention relates to a method for the autonomous and driver-independent operation of a motor vehicle equipped with an electrically controllable steering device, with at least one electrically controllable braking device and with an electrically controllable drive device, comprising at least the following steps:

1. a) detecting surrounding the motor vehicle Egodaten and the motor vehicle environment environment data, and then
2. b) determining a starting from the current position of the motor vehicle and safe in terms of a collision with obstacles by the motor vehicle passable driving tube based at least on the basis of the environment data, and then
3. c) autonomous guidance of the motor vehicle along a first trajectory of passable trajectories, which are located within the safely passable driving tube.

1. a) Wenigstens eine Sensoreinrichtung, welche das Kraftfahrzeug betreffende Egodaten und das Kraftfahrzeugumfeld betreffende Umfelddaten erfasst,
2. b) elektronische Mittel, welche mit der wenigstens einen Sensoreinrichtung zusammen wirken und ausgebildet sind, dass sie einen von der momentanen Position des Kraftfahrzeugs ausgehenden und im Hinblick auf eine Kollision mit Hindernissen durch das Kraftfahrzeug gefahrlos befahrbaren Fahrschlauchs wenigstens auf der Basis der Umfelddaten ermitteln, und
3. c) welche das Kraftfahrzeug entlang einer ersten Trajektorie von befahrbaren Trajektorien autonom führen, welche sich innerhalb des gefahrlos befahrbaren Fahrschlauchs befinden.

The invention is further based on a driver assistance system which operates a motor vehicle autonomously and driver-independently, with an electrically controllable steering device, with at least one electrically controllable braking device and with an electrically controllable drive device comprising at least the following:

1. a) at least one sensor device which records the vehicle data relating to the motor vehicle and environment data relating to the motor vehicle environment,
2. b) electronic means, which cooperate with the at least one sensor device and are designed to determine a vehicle starting from the current position of the motor vehicle and safe in terms of a collision with obstacles by the motor vehicle passable driving tube based at least on the environment data, and
3. c) which autonomously guide the motor vehicle along a first trajectory of passable trajectories, which are located within the safe passable driving tube.

Under a motor vehicle to be understood here in addition to a single vehicle here also a combination of a towing vehicle and at least one trailer.

The driving lane which can be safely driven by the motor vehicle with respect to a collision with obstacles therefore comprises a plurality of trajectories theoretically passable by the motor vehicle without causing a collision with an obstacle such as another motor vehicle or in or beside the carriageway standing object comes. This safely passable driving lane can also include a zone lying next to the lane that can also be safely driven, which then represents an emergency evasive area, for example.

The starting point of the considerations of the invention is that in a completely autonomous operation of the motor vehicle, an intervention of the driver is no longer possible and in driving dynamics critical situations therefore the autonomous driving controlling driver assistance system and in particular an autopilot device must make vehicle dynamic corrections themselves.

A driving dynamics critical situation in an autonomous operation of a motor vehicle, for example by an autopilot device, for example, arise when cornering the wheels build a high cornering force due to a high road friction coefficient and therefore at a relatively high cornering speed, there is an increased risk of tipping. Also, an obstacle suddenly appearing in front of the motor vehicle, for example a motor vehicle shattering in front of the ego vehicle, can ensure that the autopilot device adjusts a first trajectory with a relatively large steering wheel angle or steering angle in a short time, which likewise entails an increased risk of tipping over.

• d) während des autonomen Führens des Kraftfahrzeugs entlang der ersten Trajektorie eine Überprüfung dahingehend durchgeführt wird, ob eine Umkippgefahr für das Kraftfahrzeug in Bezug auf eine Längsachse des Kraftfahrzeugs besteht, und
• e1) falls das Ergebnis dieser Überprüfung ist, dass keine Umkippgefahr für das Kraftfahrzeug besteht, dann wird das Kraftfahrzeug entlang der ersten Trajektorie autonom weitergeführt,
• e2) falls aber das Ergebnis dieser Überprüfung ist, dass eine Umkippgefahr für das Kraftfahrzeug besteht, dann wird mittels der elektrisch steuerbaren Lenkeinrichtung ein Lenkeingriff autonom und fahrerunabhängig derart vorgenommen, dass das Kraftfahrzeug anstatt weiterhin entlang der ersten Trajektorie nun entlang einer zweiten, von der ersten Trajektorie verschiedenen Trajektorie von befahrbaren Trajektorien innerhalb des gefahrlos befahrbaren Fahrschlauchs geführt wird, wobei sich die zweite Trajektorie dadurch auszeichnet, dass bei einem Führen des Kraftfahrzeugs entlang der zweiten Trajektorie eine geringere Umkippgefahr oder keine Umkippgefahr mehr für das Kraftfahrzeug zu erwarten ist oder besteht.

According to the method is provided according to the invention that

• d) during the autonomous driving of the motor vehicle along the first trajectory, a check is made as to whether a risk of tipping over for the motor vehicle with respect to a longitudinal axis of the motor vehicle exists, and
• e1) if the result of this check is that there is no risk of tipping over for the motor vehicle, then the motor vehicle is autonomously continued along the first trajectory,
• e2) if, however, the result of this check is that there is a risk of tipping over for the motor vehicle, steering intervention is autonomously and driver-independently carried out by means of the electrically controllable steering device such that the motor vehicle now continues along a second, from the first, along the first trajectory Trajectory different trajectory of drivable trajectories is guided within the safely passable driving tube, wherein the second trajectory is characterized in that when driving the motor vehicle along the second trajectory a lower risk of tipping over or no risk of tipping over is expected or exists for the motor vehicle.

• d) die elektronischen Mittel weiterhin ausgebildet sind, dass sie
  • d1) wenigstens die Lenkeinrichtung elektrisch steuern oder regeln können, und
  • d2) während des autonomen Führens des Kraftfahrzeugs entlang der ersten Trajektorie eine Überprüfung dahingehend durchführen, ob eine Umkippgefahr für das Kraftfahrzeug in Bezug auf eine Längsachse des Kraftfahrzeugs besteht, und
• e) dass die elektronischen Mittel weiterhin ausgebildet sind, dass sie
  • e1) falls das Ergebnis dieser Überprüfung ist, dass keine Umkippgefahr für das Kraftfahrzeug besteht, das Kraftfahrzeug entlang der ersten Trajektorie autonom weiterführen, oder
  • e2) falls das Ergebnis dieser Überprüfung aber ist, dass eine Umkippgefahr für das Kraftfahrzeug besteht, mittels der elektrisch steuerbaren Lenkeinrichtung einen Lenkeingriff autonom und fahrerunabhängig derart vornehmen, dass das Kraftfahrzeug anstatt weiterhin entlang der ersten Trajektorie nun entlang einer zweiten, von der ersten Trajektorie verschiedenen Trajektorie von befahrbaren Trajektorien innerhalb des gefahrlos befahrbaren Fahrschlauchs geführt wird, wobei sich die zweite Trajektorie dadurch auszeichnet, dass bei einem Führen des Kraftfahrzeugs entlang der zweiten Trajektorie eine geringere Umkippgefahr oder keine Umkippgefahr mehr für das Kraftfahrzeug zu erwarten ist oder besteht.

According to the driver assistance system is provided according to the invention that

• d) the electronic means are further developed that they
  • d1) at least electrically control or regulate the steering device, and
  • d2) during the autonomous driving of the motor vehicle along the first trajectory make a check as to whether there is a risk of tipping over for the motor vehicle with respect to a longitudinal axis of the motor vehicle, and
• e) that the electronic means continue to be designed to be
  • e1) if the result of this check is that there is no danger of tipping over for the motor vehicle, autonomously continue the motor vehicle along the first trajectory, or
  • e2) if the result of this check is that there is a danger of tipping over for the motor vehicle, by means of the electrically controllable steering device autonomously and driver independently make a steering intervention such that the motor vehicle now continues along the first trajectory along a second, different from the first trajectory Trajectory of traversable trajectories is guided within the safely passable driving tube, wherein the second trajectory is characterized in that when driving the motor vehicle along the second trajectory is a lower risk of tipping or no risk of tipping more for the motor vehicle is expected or exists.

Tipping risk for the motor vehicle means for the case described above that a motor vehicle next to a single vehicle and a combination of a towing vehicle and at least one trailer is understood that the risk of tipping then exists for the towing vehicle and / or the trailer.

In other words, if it is determined that during a drive of the motor vehicle along the first trajectory, for example, in a curve there is a risk of tipping over, automatically a steering intervention, for example in the direction of the zero position or straight position of the steering wheel performed.

The steering intervention is preferably carried out by specifying a desired steering angle, a desired steering wheel angle or acting on the steering column or on the steering actuator target steering torque through which or by which a lower risk of tipping over or no risk of tipping more for the motor vehicle is to be expected.

For example, a steering intervention is performed, in which then set second steering wheel angle of the steering wheel, which then represents the new target steering wheel angle, in a range between the last set first steering wheel angle when driving along the first trajectory and the zeroing or straight-line position of the steering wheel. Then the second steering wheel angle is smaller in magnitude than the first steering wheel angle.

In addition, the steering wheel could also be adjusted beyond the zero or straight position in order to steer the motor vehicle in the other direction, in which case the second steering wheel angle is beyond the zero or straight position of the steering wheel.

Because of the then set in the direction of a lower risk of tipping new target steering wheel angle (second steering wheel angle) when driving along the second trajectory with respect to the first steering wheel angle when driving along the first trajectory, the lateral acceleration is reduced, whereby the tipping risk is reduced or eliminated , Consequently, the method according to the invention and the driver assistance system according to the invention contribute to avoiding driving-dynamics-critical situations during autonomous driving of a motor vehicle.

The measures listed in the dependent claims advantageous refinements and improvements of the first aspect of the invention are possible.

If it is determined during the check whether there is a danger of tipping over for the motor vehicle during the autonomous driving of the motor vehicle along the first trajectory, it is determined according to a preferred embodiment of the method by the at least one electrically controllable braking device a brake engagement and / or by the electrically controllable drive means made an intervention in the drive power of the drive means in the sense of reducing or eliminating the risk of tipping over for the motor vehicle. Such a braking intervention can be carried out selectively on individual wheels or on a group of wheels in order to produce a yawing moment counteracting the overturning tendency. Alternatively or additionally, for example, the drive power of the prime mover can be reduced in order to reduce the cornering speed, which also contributes to a reduction of the lateral acceleration.

In this case, according to a development of the method, the steering intervention and the braking intervention and / or the intervention in the drive power of the drive device can be carried out depending on the ego data of the motor vehicle.

In particular, at least one of the following variables can be detected as ego data of the motor vehicle: the speed of the motor vehicle, the wheel speeds of the wheels of the motor vehicle, the longitudinal acceleration of the motor vehicle, the lateral acceleration of the motor vehicle, the rate of rotation of the motor vehicle, the rolling rate of the motor vehicle, the loading of the motor vehicle , the level of the center of gravity of the motor vehicle.

For example, at a relatively high speed of the motor vehicle when cornering, the steering intervention, i. the steering wheel angle correction will be greater than at a lower speed. Furthermore, a relatively high load of the motor vehicle as well as a relatively high level of the center of gravity of the motor vehicle result in an increased tendency to overturn. Therefore, under such conditions, the steering intervention and optionally the braking intervention and / or the intervention in the drive power of the prime mover will be correspondingly extensive.

• a) bei der Überprüfung, ob während des autonomen Führens des Kraftfahrzeugs der ersten Trajektorie eine Umkippgefahr für das Kraftfahrzeug besteht, ermittelt oder geschätzt wird, ob insbesondere beim Befahren einer Kurve eine kippkritische Querbeschleunigung durch eine anhand der Egodaten ermittelten oder geschätzten Ist-Querbeschleunigung überschritten wird, und
• b1) falls dies der Fall ist, dann wird auf das Bestehen einer Umkippgefahr für das Kraftfahrzeug geschlossen, und
• b2) falls dies aber nicht der Fall ist, dann wird auf ein Nichtbestehen einer Umkippgefahr für das Kraftfahrzeug geschlossen.

According to one embodiment of the method can be provided that

• a) when checking whether there is a Umkippgefahr for the motor vehicle during autonomous driving of the motor vehicle of the first trajectory, is determined or estimated, especially if when driving a curve a kippkritische lateral acceleration is exceeded by a determined based on the ego data or estimated actual lateral acceleration , and
• b1) if this is the case, then it is concluded that there is a risk of overturning for the motor vehicle, and
• b2) if this is not the case, then it is concluded that there is no risk of tipping over for the motor vehicle.

According to a further development of the method, it can additionally be provided that when it is determined that the overturning critical acceleration is exceeded by an actual lateral acceleration determined or estimated on the basis of the ego data, a test braking force is applied to at least one wheel of the motor vehicle and based on a then adjusting Radbremsschlupfs on the at least one wheel and / or based on a then adjusting wheel speed on the at least one wheel and / or based on a then from an inactive state to an active state transitional brake slip control on the at least one wheel to the existence of a risk of tipping over the motor vehicle is closed. In this case, the at least one wheel may be a curve-internal wheel of the curve traveled by the motor vehicle. A variant of this development is therefore based on the fact that the motor vehicle is equipped with a brake slip control.

Therefore, if it is determined that in particular during a (determined) cornering of the motor vehicle, the actual lateral acceleration exceeds a critical lateral acceleration and optionally additionally, for example, the ABS is automatically activated on at least one inside wheel, because the wheel brake slip increases due to the then small Radaufstandskraft so leaves this is indicative of an existence of a risk of tipping over for the motor vehicle.

Furthermore, according to a further development of the method, the determination of the safely passable driving tube may include determining border trajectories for the motor vehicle, which limit the driving tube and are each part of it. These Grenztrajektorien be formed for example by lane or lane boundaries, with a safety margin between the Grenztrajektorien and the lane or lane boundaries can be provided. Alternatively, at least one Grenztrajektorie but also lie outside the road, when the motor vehicle is safe up to there. can drive without obstacles.

Preferably, according to a development of the method, the first trajectory used is an ideal trajectory which fulfills or exceeds a predefined minimum requirement with regard to at least one of the following criteria: travel time, route, fuel consumption, wear and / or driving safety. For example, this ideal trajectory lies approximately in the middle of a lane of a roadway. However, this ideal trajectory must be abandoned if there is an intolerable risk of tipping when driving through the motor vehicle.

1. a) die wenigstens eine elektrisch steuerbare Bremseinrichtung und/oder die elektrisch steuerbare Antriebseinrichtung steuern oder regeln können, und
2. b) dass falls sie bei der Überprüfung, ob während des autonomen Führens des Kraftfahrzeugs entlang der ersten Trajektorie eine Umkippgefahr für das Kraftfahrzeug besteht, feststellen, dass eine Umkippgefahr für das Kraftfahrzeug besteht, dann steuern oder regeln sie zusätzlich die wenigstens eine elektrisch steuerbare Bremseinrichtung durch einen Bremseingriff und/oder die elektrisch steuerbare Antriebseinrichtung durch einen Eingriff in die Antriebsleistung im Sinne einer Reduzierung oder Beseitigung der Umkippgefahr für das Kraftfahrzeug.

According to a development of the driver assistance system, the electronic means are designed to be

1. a) the at least one electrically controllable braking device and / or the electrically controllable drive device can control or regulate, and
2. b) that, if it finds in the review of whether during the autonomous driving of the motor vehicle along the first trajectory Umkippgefahr for the motor vehicle, that a Umkippgefahr for the motor vehicle, then they control or regulate additionally the at least one electrically controllable braking device a braking intervention and / or the electrically controllable drive means by an intervention in the drive power in the sense of reducing or eliminating the risk of tipping over for the motor vehicle.

Furthermore, in the driver assistance system, the electronic means may be designed such that the steering intervention and the braking intervention and / or the engagement in the drive power of the drive device are performed depending on the ego data of the motor vehicle.

According to a preferred embodiment of the driver assistance system, the sensor device is designed such that it detects at least one of the following variables as ego data of the motor vehicle: the speed of the motor vehicle, the wheel speeds of the wheels of the motor vehicle, the longitudinal acceleration of the motor vehicle, the lateral acceleration of the motor vehicle, the rotation rate of the motor vehicle, the roll rate of the motor vehicle, the loading of the motor vehicle, the level of the center of gravity of the motor vehicle.

• a) sie bei der Überprüfung, ob während des autonomen Führens des Kraftfahrzeugs der ersten Trajektorie eine Umkippgefahr für das Kraftfahrzeug besteht, ermitteln oder schätzen, ob insbesondere beim Befahren einer Kurve eine kippkritische Querbeschleunigung durch eine anhand der Egodaten ermittelten oder geschätzten Ist-Querbeschleunigung überschritten wird, und
• b1) falls sie feststellen, dass dies der Fall ist, auf das Bestehen einer Umkippgefahr für das Kraftfahrzeug schließen, und
• b2) falls sie aber feststellen, dass dies nicht der Fall ist, auf ein Nichtbestehen einer Umkippgefahr für das Kraftfahrzeug schließen.

Furthermore, according to a preferred embodiment of the driver assistance system, the electronic means may be designed such that

• a) they determine or estimate whether, when driving a curve, a tilt-critical lateral acceleration is exceeded by an actual lateral acceleration determined or estimated on the basis of the ego data when checking whether there is a risk of tipping over during the autonomous driving of the motor vehicle of the first trajectory , and
• (b1) if they find that this is the case, conclude that there is a risk of overturning the vehicle, and
• b2) if they conclude that this is not the case, conclude that there is no risk of overturning the motor vehicle.

According to a development, the electronic means may additionally be designed such that, if they determine that, in particular during the (determined) driving on the curve, a critical lateral acceleration is exceeded by the actual lateral acceleration determined or estimated on the basis of the ego data, at least one electrically controllable braking device causes on at least one wheel of the motor vehicle to apply a test braking force and then based on a then adjusting Radbremsschlupfs on the at least one wheel and / or based on a then adjusting wheel speed on the at least one wheel and / or then one of an inactive state to an active state passing brake slip control on the at least one wheel on the existence of a risk of tipping over for the motor vehicle. In this case, the least one wheel is preferably a curve-internal wheel of the curve traveled by the motor vehicle.

Also, the electronic means may be formed in the driver assistance system, that the determination of the safely passable driving tube includes determining Grenztrajektorien for the motor vehicle, which limit the travel tube and are each part of it.

Also in the driver assistance system, the electronic means may be designed such that they use as the first trajectory an ideal trajectory which meets or exceeds a predetermined minimum requirement with regard to at least one of the following criteria: travel time, route, fuel consumption, wear and / or driving safety.

The invention also includes motor vehicles with a driver assistance system described above, as well as a motor vehicle, which is operated by a method described above.

list of figures

• 1 eine schematische Darstellung eines Fahrerassistenzsystems eines Kraftfahrzeugs gemäß einer bevorzugten Ausführungsform der Erfindung;
• 2 eine schematische Darstellung eines Kraftfahrzeugs, welches gemäß einer bevorzugten Ausführungsform eines Verfahrens nach der Erfindung betrieben wird;
• 3 eine Rückansicht des Kraftfahrzeugs von 2;
• 4 ein Ablaufplan der bevorzugten Ausführungsform des Verfahrens.

An embodiment of the invention is illustrated in the drawing and explained in more detail in the following description. In the drawing shows

• 1 a schematic representation of a driver assistance system of a motor vehicle according to a preferred embodiment of the invention;
• 2 a schematic representation of a motor vehicle, which is operated in accordance with a preferred embodiment of a method according to the invention;
• 3 a rear view of the motor vehicle of 2 ;
• 4 a flowchart of the preferred embodiment of the method.

Description of the embodiment

1 is a schematic representation of a driver assistance system 1 of a motor vehicle 4 according to a preferred embodiment of the invention. The driver assistance system 2 includes an autopilot device which autonomously controls the operation of the motor vehicle. For this purpose, the autopilot device has an electronic autopilot control device 2 , in which the motor vehicle 4 relevant environment data from an environment sensor device 6 be controlled, which, for example, the motor vehicle 4 arranged lidar sensors, radar sensors, infrared sensors and / or video cameras. The environment data then provide information about in the environment of the motor vehicle 4 located objects such as other motor vehicles, stationary and moving obstacles but also about lane and lane boundaries.

Based on the environment data then determines the autopilot controller 2 one of the motor vehicle safely passable driving tube 8th ( 2 ), which comprises a plurality of safely traversable trajectories, without causing a collision with an obstacle such as another motor vehicle or a lane in or adjacent to the motor vehicle 10 a roadway 12 arranged or standing object comes. Such a driving tube 8th exists for example in the right lane 10 the roadway, as in 2 from the motor vehicle 4 is driven. The driving tube 8th or the right lane 10 Here, for example, be free of obstacles, with the autopilot controller 2 the car 4 for example, along an ideal trajectory 14 leads, for example, approximately in the middle of the right lane 10 lies. In the example follows the lane 10 or the roadway 12 and with it the ideal trajectory 14 a left turn.

The autopilot controller 2 works with an electronic processing unit 16 together so that these are determined by the autopilot control device 2 data obtained in relation to the ideal trajectory 14 Set commands to a steering actuator of an electrically operated steering device 18 For example, in the form of a first target steering wheel angle, for example, wheel-related to wheels 28 arranged electrically operated wheel brake devices 20 For example, in the form of first desired braking torque and to an electrically operable engine of the motor vehicle, for example in the form of a first target speed via, for example, a data bus 22 of the motor vehicle 4 outputs, thus the arithmetic unit 16 as a result of these setpoints, these facilities 18 . 20 of the motor vehicle controls so that this the ideal trajectory 14 can follow. In addition, the electronic processing unit 16 also, for example, an electrically actuated transmission device of the motor vehicle 4 in accordance with a then to be set first desired gear stage press. For clarity, are in 2 only the steering device 18 and the wheel brake devices 20 shown. In the case of an electro-pneumatic braking system (EBS) are the wheel brake devices 20 formed for example by pressure control modules, wherein in the arithmetic unit then the brake control unit of the EBS is integrated, for example. In such pressure control modules, for example, a 2 Channel pressure control module 2 arranged on different sides pneumatic wheel-related brake cylinder independently and ventilate and regulate the brake pressures in the brake cylinders individually, or a 1 Channel pressure control module 2 regulates the brake pressure on different sides arranged pneumatic wheel-related brake cylinder together.

These are the arithmetic unit 16 , the electrically operated steering device 18 , the electrically operated wheel brake devices 20 , the electrically actuatable drive machine and the electrically actuatable transmission device of the motor vehicle, for example, to a common data bus (CAN) 22 connected. Via signal lines 24 receives the arithmetic unit 16 from corresponding sensors data about the actual variables of said devices such as the actual steering wheel angle (steering wheel angle sensor) or the actual steering torque, the respective actual braking torque (eg brake pressure sensor) of a wheel brake device 20 , the actual speed of the prime mover (speed sensor) and the actual gear stage of the transmission device. Furthermore, the arithmetic unit receives 16 also wheel speed signals from at the wheels 28 the motor vehicle arranged wheel speed sensors.

In addition, on the motor vehicle 4 also an ego sensor device 32 present, which the motor vehicle 4 self-related ego data captured. To the ego data of the motor vehicle 4 count in particular the following sizes: The speed of the motor vehicle 4 , the wheel speeds of the wheels 28 of the motor vehicle 4 , the longitudinal acceleration of the motor vehicle 4 , the lateral acceleration ay of the motor vehicle 4 , the loading of the motor vehicle 4 , the level of the center of gravity 30 of the motor vehicle 4 ,

The ego sensor device detects the ego data 32 For example, the above-mentioned wheel speed sensors, a longitudinal acceleration sensor, a lateral acceleration sensor, a yaw rate sensor, pressure sensors in air bags of an air suspension device of the motor vehicle 4 etc., from whose sensor signals the above-mentioned variables can be derived directly or indirectly.

In the present embodiment, it is assumed that a lateral acceleration sensor of the EGO sensor device 32 Transverse acceleration signals in the arithmetic unit 16 einsteuert. Furthermore, be the motor vehicle 4 equipped with a brake slip control (ABS), which requires the wheel speed signals of the wheel speed sensors to calculate the wheel speeds, the reference vehicle speed and the wheel-specific brake slip. The arithmetic unit 16 Then, a signal from the brake slip control in terms of their condition, ie active brake slip control in the case of a detected inadmissible brake slip or inactive brake slip control in the case of a detected allowable brake slip is supplied. Preferably, the brake slip control is here in the arithmetic unit 16 implemented.

Furthermore, in the arithmetic unit 16 Implemented routines, by which it can be judged whether a risk of tipping over for the motor vehicle 4 with respect to its longitudinal axis (X direction in FIG 2 ) or not, the longitudinal axis pointing in the direction of travel. During the autonomous driving of the motor vehicle 4 along the ideal trajectory 14 is therefore from the arithmetic unit 16 a check is made as to whether there is a risk of tipping over for the motor vehicle 4 when driving on the left turn.

This check includes, for example, a check as to whether the detected by the lateral acceleration sensor actual lateral acceleration ay in Y Direction according to 2 and 3 is greater than an example predetermined tilt-critical lateral acceleration. Will this be done by the arithmetic unit 16 is determined, it is further checked whether driving the left-hand bend along the ideal trajectory 14 the brake slip control on at least one inside wheel changes from the inactive state to the active state, ie that the wheel contact force on the at least one inside wheel is reduced to such an extent that the brake slip there is inadmissible and therefore the wheel in question brakes.

All this should apply here, for example, because, for example, the coefficient of friction of the right lane 10 , the speed of the motor vehicle 4 when driving on the left-hander as well as the load and also the level of the center of gravity 30 of the motor vehicle 4 in 3 in Z Direction are relatively high. This situation is in 3 shown in which the lateral acceleration ay idealized in the center of gravity 30 of motor vehicle 4 attacks. Consequently, those in the arithmetic unit close 16 implemented routines on the existence of a specific risk of tipping over.

To avoid the tipping now prevents the arithmetic unit 16 a continuation of the motor vehicle 4 along the ideal trajectory 14 by placing control commands to the steering device 18 sends, for example, to specify a new target value for a second steering wheel angle, which is smaller in magnitude than the first target steering wheel angle, on which the of the motor vehicle 4 previously used ideal trajectory 14 results. Consequently, here the arithmetic unit displaces 16 For example, the first target steering wheel angle in the direction of neutral or zero position of the steering wheel to a smaller second target steering wheel angle, for example by a corresponding control of an electrically actuated Lenkaktuators the steering device 18 , For example, in the arithmetic unit 16 implemented steering wheel angle control then adjusts the detected actual steering wheel angle to the new second target steering wheel angle. As by the arrows 34 in 2 indicated, the motor vehicle 4 then steered towards the outside of the bend, but without the lane 10 predetermined passable driving tube 8th to leave.

The new second target steering wheel angle causes the motor vehicle 4 no longer along the ideal trajectory 14 moves, but along a second trajectory with a comparatively larger radius of curvature. The arithmetic unit 16 has previously been determined by the autopilot controller 2 transmitted data concerning the passable driving tube 8th Check if the second trajectory 26 within this drivable travel tube 8th lies. Because a second trajectory 26 outside of this drivable travel tube 8th would from the routines of the arithmetic unit 16 not allowed.

The enlarged curve radius of the second trajectory 26 leads here, for example, that the lateral acceleration ay of the motor vehicle 4 reduced to below the tilt-critical lateral acceleration and that the ABS is deactivated on the at least one inside wheel. Consequently, the risk of tipping is thereby eliminated.

In addition, the arithmetic unit 16 also a new second setpoint speed value for the drive device and new second setpoint braking torques for the wheel brake devices 20 pretend to the motor vehicle 4 to the second trajectory 26 to bring or keep it there. In particular, by individually controlling the wheel brake devices 20 a braking are initiated, which is a tipping over of the motor vehicle 4 counteracts. Last but not least, the transmission device of the motor vehicle 4 according to a newly set second target gear by the arithmetic unit 16 to be controlled.

4 now shows a flow chart of the preferred embodiment of the method. In one step 100 become the motor vehicle 4 relevant ego data from the ego sensor device and the environment data relating to the motor vehicle environment from the environment sensor device 6 detected. In one step 200 becomes one of the current position of the motor vehicle 4 outgoing and in the event of a collision with obstacles by the motor vehicle 4 safely accessible driving lane determined on the basis of the environment data. According to step 300 then becomes a motor vehicle 4 along a first trajectory (eg ideal trajectory) 14 autonomously guided by drivable trajectories, which are within the safely passable driving tube 8th are located.

In step 400 is then during the autonomous driving of the motor vehicle 4 along the first trajectory 14 a check is made as to whether there is a risk of tipping over for the motor vehicle 4 with respect to a longitudinal axis of the motor vehicle 4 consists.

If the result of this check is that there is no risk of tipping over for the motor vehicle 4 consists ( N ), then the motor vehicle according to step 500 along the first trajectory 14 autonomously continued.

If the result of this check is that a risk of tipping over for the motor vehicle 4 consists ( J ), then the motor vehicle 4 according to step 600 by means of the electrically controllable steering device 18 due to a corresponding control by the arithmetic unit 16 a steering intervention autonomously and driver independently made such that the motor vehicle 4 instead of continuing along the first trajectory 14 now along a second, from the first trajectory 14 different trajectory 26 of drivable trajectories within the safely passable driving lane 8th is guided, wherein the second trajectory 26 characterized in that when driving the motor vehicle 4 along the second trajectory 26 a lower risk of tipping or no risk of tipping more for the motor vehicle 4 is expected or exists.

LIST OF REFERENCE NUMBERS

1

Driver assistance system

2

Autopilot controller

4

motor vehicle

6

Environment-sensor device

8th

driving tube

10

lane

12

roadway

14

Ideal trajectory ( 1 .Trajektorie)

16

computer unit

18

steering device

20

Wheel brake devices

22

bus

24

signal lines

26

second trajectory

28

wheel

30

main emphasis

32

Ego-sensor device

34

arrows

Claims (18)

Method for the autonomous and driver-independent operation of a motor vehicle (4) equipped with an electrically controllable steering device (18), with at least one electrically controllable braking device (20) and with an electrically controllable drive device, comprising at least the following steps: a) detection of the motor vehicle Ego data and environment data relating to the motor vehicle environment, and then b) determining at least on the basis of the environmental data a driving tube (8) emanating from the instantaneous position of the motor vehicle (4) and safely traversable with respect to a collision with obstacles by the motor vehicle (4), and then c) autonomously guiding the motor vehicle (4) along a first trajectory (14) of passable trajectories which are located inside the safely passable driving tube (8), characterized in that d) during the autonomous driving of the motor vehicle (4) along the first trajectory ( 14) a check is made as to whether there is a risk of tipping over for the motor vehicle (4) with respect to a longitudinal axis of the motor vehicle (4), and e1) if the result of this check is that there is no tipping over risk for the motor vehicle (4), then the motor vehicle (4) is autonomously continued along the first trajectory (14), e2) but if the result of this check is that there is a risk of tipping over for the motor vehicle (4), then a steering intervention takes place by means of the electrically controllable steering device (18) autonomously and independently of the driver, in such a way that the motor vehicle, instead of continuing along the first trajectory (14), is guided along a second trajectory (26) of drivable trajectories within the safely drivable driving tube (8), which is different from the first trajectory (14), wherein the second trajectory (26) is characterized in that when driving the motor vehicle (4) along the z far trajectory (26) a lower risk of tipping over or no risk of tipping more for the motor vehicle (4) is to be expected or exists. Method according to Claim 1 , characterized in that the steering intervention is performed by specifying a desired steering angle, a desired steering wheel angle and / or a desired steering torque. Method according to Claim 1 or 2 , characterized in that if, in the check, whether during the autonomous driving of the motor vehicle 84) along the first trajectory there is a risk of tipping over for the motor vehicle (4), it is determined that a risk of tipping exists for the motor vehicle (4), then ( In addition, by the at least one electrically controllable braking device (20) a braking intervention and / or made by the electrically controllable drive means an intervention in the drive power of the drive means in the sense of reducing or eliminating the risk of tipping over for the motor vehicle (4). Method according to Claim 3 , characterized in that the steering intervention and the braking intervention and / or the engagement in the drive power of the drive device are performed depending on the ego data of the motor vehicle (4). Method according to one of the preceding claims, characterized in that as Egodaten the motor vehicle (4) at least one of the following variables are detected: the speed of the motor vehicle (4), the wheel speeds of the wheels of the motor vehicle, the longitudinal acceleration of the motor vehicle (4) Transverse acceleration (ay) of the motor vehicle (4), the rate of rotation of the motor vehicle (4), the roll rate of the motor vehicle (4), the load of the motor vehicle (4), the level of the center of gravity (30) of the motor vehicle (4). Method according to one of the preceding claims, characterized in that a) when checking whether during the autonomous driving of the motor vehicle (4) of the first trajectory (14) a risk of tipping over for the motor vehicle (4) is determined or estimated, whether a tipping-critical lateral acceleration is exceeded by an actual lateral acceleration (ay) determined or estimated on the basis of the ego data, and b1) if this is the case, then the existence of a risk of tipping over for the motor vehicle (4) is concluded, and b2) if this is not the case, then it is concluded that there is no risk of tipping over for the motor vehicle (4). Method according to one of the preceding claims, characterized in that the determination of the safely passable driving tube (8) includes determining Grenztrajektorien for the motor vehicle, which limit the driving tube (8). Method according to one of the preceding claims, characterized in that the first trajectory (14) is an ideal trajectory which exceeds a predetermined minimum requirement with regard to at least one of the following criteria: travel time, driving distance, fuel consumption, wear, driving safety. Driver assistance system (1), which operates a motor vehicle (4) autonomously and driver-independent, with an electrically controllable steering device (18), with at least one electrically controllable braking device (20) and with an electrically controllable drive device further comprising at least the following: a) at least one sensor device (6, 32), which captures the motor vehicle (4) related ego data and the motor vehicle environment environment data, b) electronic means (2, 16), which cooperate with the at least one sensor device (6, 32) and are designed to determine at least on the basis of the environmental data a driving tube starting from the instantaneous position of the motor vehicle (4) and safely traversable with respect to a collision with obstacles by the motor vehicle (4), and c) which drives the motor vehicle (4) along a first trajectory ( 14) autonomously traversable trajectories, which was within the gefah rls passable driving tube (8), characterized in that d) the electronic means (2, 16) are further adapted to be able to electrically control at least the steering device (18) d1) and d2) during the autonomous guiding of the Motor vehicle (4) along the first trajectory (14) make a check as to whether a risk of tipping over for the motor vehicle (4) with respect to a longitudinal axis of the motor vehicle (4), and e) that the electronic means (2, 16) continue are designed to e1) if the result of this review is that there is no risk of tipping over for the motor vehicle (4) autonomously continue the motor vehicle (4) along the first trajectory, or e2) if the result of this review is that Tilting danger for the motor vehicle (4), by means of the electrically controllable steering device (18) autonomously perform a steering intervention and driver independently such that the Motor vehicle (4) instead of further along the first trajectory (14) along a second, of the first trajectory (14) different trajectory of traversable trajectories within the safe passable driving tube (8) is guided, wherein the second trajectory (26) thereby characterized in that when driving the motor vehicle (4) along the second trajectory (26) is a lower risk of tipping over or no risk of tipping more for the motor vehicle (4) is expected or exists. Driver assistance system after Claim 9 , characterized in that the electronic means (2, 16) are formed such that the steering intervention is performed by presetting a desired steering angle, a desired steering wheel angle and / or a desired steering torque. Driver assistance system after Claim 9 or 10 characterized in that the electronic means (2, 16) are arranged to: a) control or regulate at least one electrically controllable braking device (20) and / or the electrically controllable drive means, and b) that, if checked whether there is a risk of tipping over for the motor vehicle (4) during the autonomous driving of the motor vehicle (4) along the first trajectory (14), determine that there is a risk of tipping over for the motor vehicle (4), then additionally control or regulate the at least one tipping vehicle electrically controllable braking device (20) by a braking intervention and / or the electrically controllable drive means by an intervention in the drive power in the sense of reducing or eliminating the risk of tipping over for the motor vehicle (4). Driver assistance system after Claim 11 , characterized in that the electronic means (2, 16) are designed such that the steering intervention and the braking intervention and / or the engagement in the drive power of the drive device are performed depending on the ego data of the motor vehicle (4). Driver assistance system according to one of Claims 9 to 12 , characterized in that the at least one sensor device (6, 32) is designed such that it detects as Egodaten the motor vehicle (4) at least one of the following variables: the speed of the motor vehicle (4), the wheel speeds of the wheels (28) of Motor vehicle, the longitudinal acceleration of the motor vehicle (4), the lateral acceleration (ay) of the motor vehicle (4), the rate of rotation of the motor vehicle (4), the roll rate of the motor vehicle (4), the load of the motor vehicle (4), the level of the center of gravity ( 30) of the motor vehicle (4). Driver assistance system according to one of Claims 9 to 13 , characterized in that the electronic means (2, 16) are designed such that a) it consists in checking whether during the autonomous driving of the motor vehicle (4) along the first trajectory (14) a risk of tipping over for the motor vehicle (4) , ascertain or estimate whether a lateral acceleration that is critical to a fall-off is exceeded by an actual lateral acceleration (ay) determined or estimated on the basis of the ego data, and b1) if it then determines that this is the case, then a risk of tipping over for the motor vehicle ( 4), and b2) if they conclude that this is not the case, conclude that there is no risk of tipping over the motor vehicle (4). Driver assistance system according to one of Claims 9 to 14 , characterized in that the electronic means (2, 16) are designed so that the determination of the safe passable driving tube (8) includes determining Grenztrajektorien for the motor vehicle (4), which limit the driving tube (8). Driver assistance system according to one of Claims 9 to 15 , characterized in that the electronic means (2, 16) are designed such that they use as the first trajectory (14) an ideal trajectory which meets or exceeds a predetermined minimum requirement with respect to at least one of the following criteria: travel time, driving distance, fuel consumption, Wear and / or driving safety. Motor vehicle (4) with a driver assistance system (1) according to at least one of Claims 9 to 16 , Motor vehicle (4) operated by a method according to at least one of Claims 1 to 8th ,

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