DE102006043150A1 - Longitudinal guide assistant for motor vehicle, has commanding device displaying speed command during distance-regulated following of motor vehicle at given distance from ahead-driving vehicle, and when identifying gap on target lane - Google Patents

Abstract

The assistant has an identification unit for identifying a gap for a safe pass of a motor vehicle (KFZ) on a target lane (ZS) based on data of an environment sensor. A deciding device decides whether a lane change (w) of a driver is accepted. A commanding device (BE) displays a speed command in case of the lane change during a distance-regulated following of the motor vehicle at a given distance from an ahead-driving vehicle (vF1), and when identifying the gap on the target lane based on a transverse movement of the motor vehicle.

Description

The The invention relates to a longitudinal guidance assistant for a motor vehicle for support of the driver when changing lanes from a momentary track to a Target track according to the preamble of claim 1.

Increasingly Motor vehicles are equipped with more and more driver assistance systems, the On the one hand, to assist the driver in carrying out certain driving maneuvers and on the other hand intervene in critical situations or on the Driver issue a warning. To assist the driver in the longitudinal control his motor vehicle, for example, distance-related speed control systems known in which the speed of the vehicle either on a predetermined speed, or, if a preceding one Vehicle is present at a predetermined distance to this preceding vehicle is regulated. When changing lanes during one such follow-up drive must be the distance-related speed control system either temporarily disabled, overridden by the driver, or on the destination lane vehicle to be switched to the approaching and driving past the vehicle ahead on the starting lane to enable.

Of Furthermore, there are driver assistance systems, which the driver in the Transverse control of his motor vehicle with regard to driving within his Support lane. These systems support the driver while lane keeping by an additionally applied to the steering wheel Steering torque in the direction of the center of the lane and / or warn if necessary acoustically and / or by vibrations in the steering wheel from an unintentional Leave your own lane.

If the driver wants to make a lane change while actively supporting the lateral guidance, such systems are a hindrance since they always steer the vehicle in the direction of the lane and / or irritate the driver due to the warnings. To circumvent this problem, in a method according to the DE 10 2004 012 144 A1 the steering intervention prevented when a lane change is detected.

Just for the Lane change requiring more attention from the driver, Thus, systems are important to give the driver the lane change of one Momentary track on a neighboring track easier.

This is from the DE 102 10 723 A1 a lane change assistant is known, which controls the dynamic movement of the current track to the target track differently dynamic when detecting a lane change intent of the driver in response to the operation of a corresponding control element. If the motor vehicle additionally has an automatic longitudinal guidance system, the locating range of a radar present in the vehicle can additionally be adapted in accordance with the lane change and / or the driving speed when changing lanes can be increased in dependence on the emitted signal of the aforementioned operating element.

The DE 197 25 656 A1 discloses an overtaking assistant that calculates an overtaking distance and / or an overtaking time upon detecting a lane change intent in response to the detected preceding and returning vehicles. If no safe overtaking is possible, the driver is warned. If the driver does not react to this, it is additionally possible to intervene in the steering and / or the braking system and / or a power control of the drive unit in such a way that the overtaking maneuver carried out by the driver is prevented.

Finally, out of the DE 10 2004 029 369 A1 a lane change assistant for motor vehicles with a speed control system according to the preamble of claim 1. If a lane change request is detected and there is a sufficient gap on the target lane, an acceleration strategy adapted to the gap is calculated, including the time for the beginning of the acceleration. One approach for determining the acceleration strategy is to set an appropriate value for the acceleration and the target speed to be achieved by the latest possible lane change time, taking into account the acceleration capability of the motor vehicle and from a comfort point of view. An alternative approach is that, depending on the distance of the motor vehicle to the vehicle in front on the target track and / or depending on the distance of the motor vehicle rear vehicle on the target lane, an optimal, characterized by the lowest possible accelerations path / time curve is set, from which the acceleration profile is derived. The steering maneuver for the actual lane change is up to the driver. To prevent too close to the preceding vehicle by the automatic acceleration, the acceleration at a predetermined distance, which is slightly greater than the necessary safety distance, canceled if the driver does not perform necessary for the lane change steering maneuver. This may happen that the motor vehicle is accelerated when recognized lane change request, and then braked again when the driver despite lane change request but no corresponding steering maneuver performs. This leads to an uncomfortable driving behavior.

task The invention is now, with regard to safety and the ride comfort improved device to support the Driver of a motor vehicle at the lane change from a momentary track indicate an adjacent destination lane.

These Task is by a longitudinal guidance assistant solved according to claim 1. Advantageous developments emerge from the dependent claims.

Of the The invention is based on the finding that the driver without independent lane change without support takes into account all relevant surrounding vehicles and its lane change tuned to it. This is in particular when Einscheren in terse Gaps important in the column traffic. In these cases, a predictive driver accelerates even before the lane change, shortened the distance to the front vehicles on the instantaneous and target lane to an appropriate extent, shave on the target track and leaves afterwards fall back a bit, in reasonable around the new preceding vehicle on the finish track Distance to follow. This strategy allows him a lane change in tight spaces.

Of the Longitudinal guidance assistant according to the invention for a Motor vehicle for support of the driver when changing lanes from a momentary track to a Target track includes an environment sensor for detecting the traffic environment including Traffic on a destination lane, a detection device, the is designed to, based on the data of the environment sensors a gap for a safe Engines to recognize the target lane, a decision maker to decide whether to accept a lane change request of the driver is and a command device, in the case of a lane change request and upon detection of a sufficient gap for safe shredding on the target track an acceleration command to the distance-related Speed control system outputs. Will the lane change request and the sufficient gap while one made by the distance-related speed control system distance-controlled follow-on drive of the motor vehicle with a predetermined Distance to a preceding vehicle detected gives the command device dependent on from the transverse movement of the motor vehicle from an acceleration command. This relationship can ensure that the driver not only has a lane change request displayed, but this indeed carry out want. Only when the driver performs a lane change corresponding steering maneuver is an acceleration command issued by the conventional, by the distance-related speed control system during a Following drive generated acceleration command deviates.

A advantageous design of the command device is characterized in that that the command device is not in the acceleration strategy of the conventional distance-related cruise control system intervenes until the motor vehicle up to a predetermined distance to the preceding vehicle has opened up. Only then will acceleration commands become dependent issued by the transverse movement of the motor vehicle. Through this Acceleration commands will be the actuators of an acceleration and / or deceleration system so controlled that a corresponding acceleration or speed or a reduced preset distance.

A further advantageous design is characterized in that position, Distance, speed and possibly acceleration of one on the target track rearward approaching Vehicle are evaluated to the start time of the acceleration commands to determine so that a beginning lane change the rearward vehicles signaled on time, but an unnecessary disability due to premature Lane change beginning is avoided.

advantageously, the acceleration command is designed such that the distance to the vehicle ahead on the current lane in dependence from the transverse overlap of the own motor vehicle to this preceding vehicle continuously reduced a predetermined reduced distance becomes. So is a lane change request during the by the speed control system carried out distance-controlled subsequent journey of the motor vehicle with detected a predetermined distance to a preceding vehicle, becomes dependent from the transverse overlap given a reduced distance and from this specification of the acceleration command issued to reach the reduced distance. Thus regulates the distance related speed control system during the Follow-up ride is no longer set to a generally constant Distance, but to the continuously changing reduced distance.

With complete overlap, the reduced distance can either correspond to the distance predetermined by the speed control system, or already to a distance actually reduced to this distance. Depending on the decreasing transverse overlap of the motor vehicle Vehicle to the vehicle in front thus takes place automatically unlocking the vehicle in front.

advantageously, may be the default value set by the acceleration command reduced distance a determined minimum distance to the preceding vehicle Vehicle on the current track not fall below. This safety distance is necessary for a sudden Danger situation still the possibility is to avoid a rear-end collision. Likewise, the must Safety distance to a vehicle in front on the destination lane be respected. The minimum distance can be fixed or depending of different parameters, for example the instantaneous speed or the driving behavior of the driver to be variable.

advantageously, is the reduced distance depending on the speed of the motor vehicle and / or the relative speed and / or Relative acceleration of the vehicles in front and / or a rearward vehicle specified on the lane to the motor vehicle or calculated depending on the situation. It can too still other parameters are queried and into the respective determination of the reduced distance.

advantageously, can also be the rear vehicle on the destination lane in the control strategy or in the determination of the Incorporate acceleration command and lead to a correction of the acceleration command. Remains for example, the distance between the motor vehicle and the rear vehicle while the entire lane change sufficiently large, will be during the lane change Acceleration command issued, which is only such a large acceleration that generates the subsequent Delay and falling back after the lane change on the destination lane with the help of a moderate, limited delay, advantageously in the magnitude of the engine drag torque, can be done and no additional Brake intervention is required. Approaching the rear vehicle however due to high relative velocity or relative acceleration so fast to the lane change exporting motor vehicle that the lane change as possible early or done quickly must be made to maintain the greatest possible distance to the rear vehicle a stronger one on the destination track Acceleration at the expense of a subsequent active deceleration of the motor vehicle by engaging the braking system to achieve the predetermined Distance to the vehicle in front on the destination lane.

This Longitudinal guide assistant is basically based insist that the driver himself contributes to the lateral movement of the vehicle Changing lanes. He can operate the steering wheel freely, d. H. it will no additional Steering torque applied to the steering wheel. Is a lane keeping assistance system or a lane departure warning system when detecting the lane change request and a sufficient gap active on the target lane, the systems for the lane change process at least partially disabled so that the driver does not interfere with steering or gets irritated.

Only, if the motor vehicle threatens due to the steering of the driver, from the road or road In an advantageous design, either a steering torque will come off generated, which moves the driver to a steering movement in the direction of the road, and / or a warning in the form of an acoustic, optical or output haptic signal.

Becomes when detecting the lane change intention no sufficient gap for a safe Engraving on the target lane, the command facility can advantageously a traverse command a transverse control system and / or an optical and / or acoustic and / or to give haptic warning. The traverse command can either be an additional Steering torque on the steering wheel lead or directly to an intervention in the wheel angle. He can, too lead to such a braking intervention that similar to a stability control system, a certain transverse guidance of the motor vehicle is reached. As mentioned above, can the transverse control system will be a lane keeping system which provides a steering torque generated on the steering wheel. The transverse command to the lateral control system should be made by the driver in the direction of the target track transverse movement counteract.

advantageously, For safety reasons, the acceleration commands and / or traversing commands are from Driver overridden at any time.

The The invention will now be explained in more detail with reference to exemplary embodiments. there demonstrate

1 an embodiment of the longitudinal guide assistant according to the invention and

2a - 2e a lane change performed according to the invention at different times to illustrate the determined acceleration command.

The 1 shows a motor vehicle KFZ on a Momentanspur MS during a distance-controlled follow-up drive with a predetermined distance to a vehicle in front vF1 on the instantaneous track MS. On a neighboring lane, the destination lane ZS, there is also a preceding vehicle Vehicle vF2 and a rear vehicle RH. The motor vehicle KFZ is equipped with a distance-related speed control system G for regulating the speed to a predetermined speed or, as here, to a predetermined distance to the vehicle in front vF1, and with a longitudinal guidance assistant LFA. The longitudinal guidance assistant LFA is used to support the driver of the motor vehicle KFZ when changing lanes from the instantaneous lane MS to the adjacent destination lane ZS during the distance-controlled following drive.

Of the Longitudinal guide assistant LFA comprises an environment sensor equipped with various sensors S US with an image processing unit BV, a detection device EK, a decision maker EN, a cross position observer Q and a command device BE.

The with various sensors S for monitoring the forward, reverse, and Side compartment of the motor vehicle equipped environment sensor US recorded in addition to preceding vehicle vF1 on the instantaneous lane MS immediately preceding, backward and lateral vehicles vF1 and rF on the target lane ZS. The sensors S can Sensors of the distance-related speed control system G and / or a lane keeping system and / or a lane departure warning system be. It can too additional Sensors S may be present, covering the rear and side area of the motor vehicle. The environment sensor US can be a component of the distance-controlled Cruise control system G or existing in the motor vehicle Be a lane keeping system.

In addition, over a in the environment sensor US integrated image processing unit BV Location, width and curvatures the lanes MS and ZS detected and the position of the surrounding vehicles vF1, vF2 and rF are determined in relation to the lanes. By storage this data for the relevant period and modeling and propagation of the vehicle condition is also a track assignment of the rear vehicle RH possible. The Image processing unit BV is not mandatory, but can also be replaced by alternative methods of lane departure become. The environment sensor US gives consideration to the speed v and the acceleration a of the motor vehicle KFZ the relevant Data such as distance d, relative velocity vrel and relative acceleration arel of the surrounding vehicles vF1, vF2 and rF to the vehicle motor vehicle to the detection device EK on.

The Recognition device EK is designed to be based on the data d, vrel and arel the environment sensors US a gap for a safe shredding to be able to recognize the target lane. Is such a gap recognizable, the detection device EK sends a signal to the lü Command device BE.

Finally, the longitudinal guidance assistant LFA comprises a decision device EN for deciding whether a lane change request of the driver of the motor vehicle KFZ is to be assumed. As soon as the start of a lane change is detected by indicators such as the setting of a turn signal or the approach to the lane boundary, the decision device EN sends a signal w to the lateral position observer Q. The lateral position observer Q then detects the transverse movement of the motor vehicle KFZ and sends a corresponding signal r the command device BE. In the case of a lane change request w and upon detection of a sufficient gap lü, the command device BE then outputs an acceleration command l to the speed control system G present in the vehicle for safe shearing onto the target lane ZS as a function of the transverse movement r of the motor vehicle KFZ. The acceleration command I is designed in such a way that as a function of the decreasing transverse overlap of the motor vehicle KFZ to the vehicle in front vF1 on the instantaneous track a continuous unlocking to the fore vehicles vF1 and vF2 takes place, whereby a sufficient safety distance is ensured. The acceleration command may additionally depend directly on the data d, vrel and arel of the rear vehicle rF. This will be closer in the 2a - 2e received.

Becomes detected by the detection device EK no sufficient gap lü or drives the motor vehicle KFZ in the direction of the lane boundary can be the command device BE also output a steering or warning command q, whereby a steering torque is generated on the steering wheel towards the center of the roadway, or one Warning is issued to the driver.

Based on 2a - 2e the acceleration a resulting from the acceleration error l of the motor vehicle KFZ is illustrated. The 2a - 2e show a lane change made according to the invention at different times.

2a shows a traffic situation in which the motor vehicle KFZ follows a momentary lane MS during a distance-controlled follow-up drive with a predetermined distance dacc a preceding vehicle vF1 on the instantaneous lane MS. For distance control, a well-known, not shown distance-related speed control system is used. The preceding vehicle vF1 on the current lane moves at a constant speed v1. In addition, on a neighboring lane, the destination lane ZS, there is a preceding vehicle vF2 with a constant speed v2 which is greater than v1 and a rear vehicle rF with a speed v1. By means of an environment sensor system (not shown here) in the motor vehicle KFZ, the immediately preceding vehicle vF2 and the rearward rF on the target lane ZS are detected on the instantaneous lane MS and the distance, the relative speed and relative acceleration to the motor vehicle KFZ are determined for each detected vehicle. Further, by means of the recognition device, not shown here, the data of the environmental sensor system is evaluated in such a way, whether there is a gap for a safe shredding on the target track. In the traffic situation shown here, a sufficient gap exists, which is why the detection device sends a corresponding signal to the command device.

Of the Driver of the motor vehicle car now intends a lane change and indicates this by pressing its turn signal BL. Thereupon recognizes the decision device not shown here a lane change request of the driver and gives a corresponding Signal to the command device. The of the command device generated acceleration commands are at Stellaktuatoren a Longitudinal control unit which is part of the cruise control system. In terms of longitudinal control the acceleration commands to the brake and / or Antriebsaktuatorik the motor vehicle Car transmitted.

2 B now shows the effect on all surrounding vehicles vF1, vF2 and rF at the beginning of the lane change. In order to impede the rearward vehicle rF as little as possible, immediately after the lane change request and the recognition of a sufficient gap on the destination lane, the command device generates an acceleration command which leads to an acceleration a and thus to a reduction in the current distance dzcc between the motor vehicle KFZ and the preceding vehicle Vehicle vF1 leads to a predetermined reduced distance d1. The predetermined by the speed control system distance dacc is reduced. The reduction of the distance dacc to the distance d1 can be done, for example, proportionally to the predetermined distance dacc.

As soon as the distance between the motor vehicle and the vehicle ahead Vehicle vF1 corresponds to the reduced distance d1 and as long as the Vehicle its transverse movement or its transverse overlap to the preceding vehicle Vehicle vF1 not changed, there is no further acceleration, d. H. the reduced distance d1 is held.

If the driver of the motor vehicle begins to pull out the vehicle, an acceleration command dependent on the transverse movement QV of the motor vehicle KF is output, see 2c , The acceleration command is then configured such that the predefined reduced distance d1 to the preceding vehicle vF1 as a function of the transverse overlap of the motor vehicle KFZ to the vehicle in front on the instantaneous lane is further continuously reduced by acceleration a of the motor vehicle KFZ. The self-adjusting distance is indicated by the reference numeral d123. When determining the continuously reduced distance d123, however, a safety distance or minimum distance dmin from the vehicles vF1 and vF2 traveling in front is taken into account, which must not be undershot for safety reasons.

Of the reduced distance d1 and also the continuously reduced distance d123 can depend on from the speed of the motor vehicle and / or the relative speed and / or relative acceleration of the preceding vehicles and / or a rear vehicle be specified on the lane to the motor vehicle.

In order to enable acceleration in gaps, it is also possible to fall below the distance dacc to the vehicle in front vF2 on the destination lane, as predetermined by the speed control system, if this leads to a lesser obstruction of the rear vehicle. So shows 2d in that in the traffic situation illustrated here after the actual lane change, the distance d3 between the motor vehicle KFZ and the preceding vehicle vF2 on the target lane ZS is less than the predetermined distance dacc.

To the lane change an acceleration command is issued, the an acceleration a or delay a of the motor vehicle leads in such a way that the distance between the motor vehicle KFZ and the preceding vehicle vF2 on the Target track ZS from distance d3 to that of the speed control system principle given distance dacc is increased.

Finally, the distance between the rear vehicle rF and the motor vehicle KFZ, the relative speed or the relative acceleration for the determination or the correction of the acceleration command can be used. At a distance between the rear vehicle rF and the motor vehicle KFZ, which exceeds a predetermined distance limit value or at a relative acceleration or relative speed of the rear vehicle to the motor vehicle, the a predetermined relative acceleration limit or Relativgeschwindig keitsgrenzwert exceeds the command means during the entire lane change of such an acceleration command, which leads only to such a large acceleration a of the motor vehicle KFZ that the required after the lane change delay of the motor vehicle to reach the speed control system predetermined distance dacc to that on the target lane preceding vehicle vF2 can be generated without braking intervention. Thus, if the distance to the rear vehicle rF remains sufficiently high during the entire lane change, acceleration is only so strong during the lane change that the subsequent deceleration and fallback can take place by means of a moderate, limited deceleration, typically the magnitude of the engine drag torque, and not an additional one Brake intervention is necessary.

Claims (8)

Longitudinal guidance assistant for a motor vehicle to assist the driver when changing lanes from a momentary track to a destination lane, with an environment sensor system for detecting the traffic environment including traffic on a destination lane, with a recognition device that is designed to use the environment sensor data to leave a gap for a safe lane Detecting shearing on the target lane, with a decision device for deciding whether to accept a lane change request of the driver and with a command device issuing an acceleration command to a cruise control system in the event of a lane change request and recognizing a sufficient gap for safe shearing onto the target lane, characterized in that the speed control system G is a distance-related speed control system G and that during a distance-controlled follow-up drive of the motor vehicle (KFZ) with a predetermined distance (dacc) on a vehicle in front (vF1) the command device (BE) in the case of a lane change request (w) and upon detection of a sufficient gap (lü) for a safe shear on the target track (ZS) in dependence on the transverse movement (QV) of the motor vehicle (vehicle ) outputs an acceleration command (l). Longitudinal guide assistant according to claim 1, characterized in that the acceleration command (l) is designed such that the predetermined distance (dacc) on the vehicle in front (vF1) depending on the transverse overlap (QV) of the motor vehicle (vehicle) to the vehicle in front (vF1) on the instantaneous track (MS) to a given reduced distance (d1, d123) is reduced. Longitudinal guide assistant according to claim 2, characterized in that by the acceleration command (l) set predetermined reduced distance (d1, d123) one determined minimum distance (dmin) to the vehicle in front (vF1) on the instantaneous lane (MS) and / or a detected preceding vehicle Vehicle (vF2) on the target lane (ZS) may not fall below. Longitudinal guide system according to claim 2 or 3, characterized in that the reduced Distance (d1, d123) depending from the speed (v) of the motor vehicle (KFZ) and / or the Relative velocity (vrel) and / or relative acceleration (arel) the preceding vehicles (vF1, vF2) and / or a rear vehicle (rF) on the target track (ZS) to the motor vehicle (motor vehicle) is specified. Longitudinal guide assistant according to one of the preceding claims, characterized in that the acceleration command issued by the command device (BE) (l) additionally is dependent on the distance (d) of a vehicle on the target track (rF). Longitudinal guide assistant according to claim 5, characterized in that at a distance (d) between the rear vehicle (rF) and the motor vehicle (KFZ), which calculated a given or situation-dependent Distance limit exceeds and / or at a relative acceleration (arel) or relative speed (vrel) of the rear vehicle (rF) to the motor vehicle (KFZ), which calculated a given or situation-dependent Exceeds relative acceleration limit or relative speed limit, the command device (BE) such an acceleration command (l) indicates that the delay required after the lane change (a) of the motor vehicle (KFZ) to reach the speed control system (G) predetermined distance (dacc) to one on the target track (ZS) preceding vehicle (vF2) is generated without braking intervention. Longitudinal guide assistant according to one of the preceding claims, characterized in that the command device (BE) in the case of a lane change request (w) when detected unavailability a sufficient gap for a safe insertion into the target lane (ZS) a lateral guidance command (q) to a transverse control system and / or an optical and / or acoustic and / or haptic warning. Longitudinal guidance assistant according to claim 7, characterized in that the transverse guidance command (q) to the transverse control system made by the driver in the direction of the target track (ZS) transverse movement counteracts.