The present invention relates to a method and a device for influencing a system that controls or regulates the position and/or the orientation of a motor vehicle with respect to a traffic lane.
The introduction of video sensors, which record the vehicle environment, makes possible new systems of active safety. Among these are systems which record the course of the traffic lane ahead of the vehicle and, when it threatens to run off the traffic lane, the systems undertake interventions in the movement of the vehicle.
German Published Patent Application No. 199 16 267 describes a method and a device for monitoring or for influencing a vehicle on a path. In this context, the method ascertains a setpoint value and an actual movement of the vehicle, executes a comparison of the setpoint path and the actual movement, and haptically transmits to the driver of the vehicle an information variable according to the comparing result, or at least controls a wheel brake according to the result of the comparison.
In today's driving stabilization systems, the driver has to perform the tracking by specifying the steering angle, even in critical situations in which many drivers have too many demands made on them. The method of the present invention supports the driver, especially in critical situations with respect to driving dynamics, by tracking which is activated, for instance, during an intervention of a vehicle dynamics control system (e.g. ESP=“electronic stability program”, FDR=“Fahrdynamikregelung” (vehicle dynamics regulation)). The method of the present invention works autonomously in the vehicle, based on video-based tracking recording. It does not require a digital map, and therefore it does not have to be updated. Furthermore, the system of the present invention need not be supported by devices in the infrastructure.
The present invention provides a method for influencing a system that controls or regulates the position and/or orientation of a motor vehicle with respect to a traffic lane (=tracking system, often denoted as a “lane-keeping system”). In this context, more important than the construction and the operating mode of the tracking system, is the control of such a system. This control of the tracking system manifests itself in that activation and deactivation of this system occurs as a function of variables of both the vehicle and the surroundings.
In a first exemplary embodiment, the tracking system according to the present invention is activated when the danger of a collision of the motor vehicle with an obstacle in the traffic lane is detected. In response to a detected obstacle in the traffic lane, a possible collision of an obstacle and the vehicle is able to be avoided by deactivating tracking.
The configuration of the first exemplary embodiment of the present invention is characterized in that the system is deactivated even if no potentially dangerous situation with respect to the driving dynamics of the motor vehicle is detected, or if clear indications are detected that the driver of the motor vehicle wants to leave the traffic lane. These deactivations provide that, in the case of driving situations recognized as not being dangerous and in the case of the detected driver command after leaving the traffic lane, there is no “making up the mind” of the driver by the tracking system. In these cases, tracking remains the task of the driver.
In a second exemplary embodiment, the tracking system is only activated when a potentially dangerous situation with respect to the driving dynamics of the motor vehicle is detected.
In an exemplary embodiment of the present invention, the tracking system is activated only if, in addition, no danger of collision of the motor vehicle with an obstacle on the traffic lane is detected, and if no clear indications are detected that the driver of the motor vehicle wants to leave the traffic lane.
A third exemplary embodiment provides that the tracking system is deactivated if a danger of a collision with an obstacle in the traffic lane is detected, and the tracking system is only activated if a potentially dangerous situation with respect to the driving dynamics of the motor vehicle is detected.
An exemplary embodiment of the present invention provides that the tracking system is deactivated even if no potentially dangerous situation with respect to the driving dynamics of the motor vehicle is detected, or if clear indications are detected that the driver of the motor vehicle wants to leave the traffic lane, and the tracking system is only activated if, in addition to the detection of a potentially dangerous situation for the driving dynamics, no danger of a collision of the motor vehicle with an obstacle on the traffic lane is detected, and no clear indications are detected that the driver of the motor vehicle wants to leave the traffic lane.
In the detection of a danger of a collision with an obstacle, the present invention provides that variables describing the geometrical course of the traffic lane, variables describing the movement of the vehicle, as well as obstacles recorded by a video system and/or a radar system, serve as an input. This provides a qualitative recording of the danger of a collision.
In addition, the present invention provides that the detection of a potentially dangerous situation with respect to the driving dynamics occurs by evaluation of variables describing the vehicle movement, and/or by the determination of whether regulating interventions influencing the driving dynamics are being performed by a driving stabilization system present in the vehicle.
Since an increasing number of vehicles are equipped with a driving stabilization system or a vehicle dynamics control system, one may therefore fall back on the sensor system of the driving stabilization system or the vehicle dynamics control system.
The present invention provides that a clear indication that the driver of the vehicle wants to leave the traffic lane is when a direction indicator is being operated by the driver or when the steering wheel angular velocity exceeds a predefinable threshold value.
Both the ascertainment of the state of the travel direction indicator and the ascertainment of the steering wheel angular velocity may be achieved using little expenditure.
The orientation of the vehicle may be determined with respect to a travel lane by the angle between the lane tangent and the longitudinal axis of the vehicle.
The system controlling or regulating the position and/or the orientation of a motor vehicle with respect to a lane may be a system autonomous to the vehicle. In this case, one is not dependent upon any external infrastructure for its operation.
The system of the present invention includes a device working autonomously to the vehicle for recording the following variables:
1. Recording travel lane variables and the course of the travel lane. This includes the determination of, for instance, the width, the curvature or the change in curvature of the travel lane. This may also include the recording of the existence of additional lanes or the recording of roadway markings (e.g. of the center line of the roadway). This is shown in block 11 of
2. Recording of the vehicle position and the vehicle orientation relative to the lane. It includes, for instance, the recording of the lateral deviation of the vehicle (lateral deviation=lateral displacement from the middle of the lane) and the recording of the angle between the travel lane tangent and the longitudinal axis of the vehicle. This is shown in block 10 of
3. The recording of obstacles, such as other vehicles or objects or living beings located on the roadway. Recorded variables are, for example, the longitudinal distance from the obstacle, the lateral deviation with respect to the obstacle or the relative speed. This is shown in block 12 of
The recording of these variables may, for instance, be done by video sensor and a postconnected evaluation unit. For the recording of obstacles, in addition to the video sensor, a radar sensor may also be used. The data from each sensor are then brought together by sensor data aggregation.
In addition to the above, the following additional variables are recorded.
4. Recording of vehicle movement variables. Variables such as the vehicle's longitudinal speed, the yaw rate of the vehicle and the transverse acceleration are recorded. (Block 13,
5. Recording of the status or the operating condition of a driving stabilization system. This includes, for example, the recording of the status of status flags of a vehicle dynamics control. A status flag of a vehicle dynamics control may indicate, for example, whether the vehicle dynamics controller is in an active mode (block 14,
6. Recording of vehicle operating variables. This includes, for example, the recording of an activation of a travel direction indicator or the recording of the steering wheel angular speed (block 15,
From the vehicle movement variables (block 13,
Furthermore, from the vehicle operating variables (block 15,
In addition, a collision danger measurement MK is ascertained, in block 16 in
In the following, the three ascertained measurements are once more summarized in abbreviated form:
Tracking regulation 19 processes the position and the angular orientation of the vehicle relative to the travel lane (block 10,
1. The yaw rate regulation of a vehicle dynamics control system (ESP system, FDR system) which, on its part, triggers wheel-selective braking interventions in order to correct the actual yaw rate of the vehicle to the setpoint yaw rate.
2. The steering angle regulation of an active steering system.
3. The steering torque regulation of an active steering system.
4. The yaw rate regulation of an active steering system which, on its part, triggers steering angle or steering torque interventions, in order to correct the actual yaw rate of the vehicle to the setpoint yaw rate.
5. The yaw rate regulation of a system for the combined regulation of several chassis systems which, on its part, triggers wheel-selective braking interventions, steering angle interventions or interventions in normal force actuators (e.g. active spring or damper elements, active stabilizers), in order to correct the actual yaw rate of the vehicle to the setpoint yaw rate.
6. The transverse speed regulation of a vehicle dynamics control system, of an active steering system or a composite regulating system which, on its part, undertakes interventions in the vehicle movement, in order to correct the actual transverse speed to the setpoint transverse speed.
Tracking regulation is activated when the following conditions are simultaneously satisfied:
1. The travel situation is critical from a driving dynamics point of view, i.e., driving dynamics measurement MF exceeds a boundary GF1.
2. The lane-leaving command measurement MV undershoots a boundary GV1.
3. The collision danger measurement MK undershoots a boundary GK1.
Tracking regulation is deactivated if:
1. driving dynamics measurement MF undershoots a boundary GF2; or
2. lane-leaving command measurement MV exceeds a boundary GV2; or
3. collision danger measurement MK exceeds a boundary GK2.
In the deactivation, a sliding transition of the tracking setpoint variable (signal 101 in
As a run-up to an intervention in the vehicle movement, further measurements may be performed (possibly having lower boundaries for the driving dynamics measurement and higher boundaries for the lane-leaving command measurement). These are, for example:
1. the triggering of reversible restraint systems (e.g. seat belt tensioners) in block 22,
2. the change in the triggering thresholds of irreversible restraint systems (such as an air bag) in block 24,
3. the triggering of signaling means (e.g. warning blinkers) for warning other traffic participants in block 23,
From the results of function blocks 10 to 15, the following three variables are now derived:
1. In block 16, the danger of a collision with obstacles is ascertained. Block 16 receives its input signals from block 11 (lane variables), from block 12 (obstacles), from block 13 (vehicle movement variables), as well as optionally from block 10.
2. In block 17, the danger of the current driving dynamics status is ascertained. This is ascertained from the vehicle movement variables in block 13 and the ascertained status of the vehicle stabilization system in block 14.
3. In block 18, indicators for a possible command of the driver for leaving the lane are ascertained. As input variables, the lane variables ascertained in block 11, the vehicle movement variables ascertained in block 13 and the vehicle operating variables ascertained in block 15 are used.
In this context, the possibility exists of also recording the results of blocks 16, 17 and 18 quantitatively. The collision danger of obstacles (in block 16) is recorded by a collision endangerment measurement MK. In block 17, a driving dynamics measurement MF is set up, and in block 18 a lane-leaving command measurement MV is set up. These measuring numbers are able to be evaluated, and also, for example, compared to threshold values. The results of these evaluations in blocks 16, 17, 18 go into evaluation logic 20 as input signals. Evaluation logic 20 makes a decision regarding an activation or a deactivation of tracking regulation 19. The activating and deactivating signals are denoted in
In this matrix the symbols > and < are to be found. In this context, in the field marked 204, the symbol > means, for example, that driving dynamics measurement MF exceeds a boundary GF1. In field 205, the symbol < means that the driving dynamics measurement MF undershoots a boundary GF1. With that, in this matrix all 8=2 * 2 * 2 possible combinations are included, namely that the driving dynamics measurement MF is able to exceed or undershoot a boundary value (2 possibilities), that the lane-leaving command measurement MV is able to exceed or undershoot a boundary value (2 possibilities), and that the collision danger measurement MK is able to exceed or undershoot a boundary value (2 possibilities).
It is possible to select, for each of these measurements, various boundary values with respect to exceeding or undershooting. This will be described now in connection with driving dynamics measurement MF.
It is assumed here that collision danger measurement MK and lane-leaving command measurement MV are very small, i.e., there is a small collision danger and there are no strong indications for a lane change command by the driver. Now, if the driving dynamics measurement exceeds a first boundary GF1, the tracking regulation is activated. However, deactivating the tracking regulation occurs only after the driving dynamics measurement undershoots a boundary GF2. In this context, it is possible to select different values for GF1 and GF2. In this manner a hysteresis behavior is brought about.
Finally,
The output signals of block 30 are supplied to blocks 31 and 32. The output signals of block 32 are supplied to blocks 31 and 33. The output signals of block 31 are supplied to block 33. Sensor arrangement 30 records the vehicle's position and orientation within the lane (see block 10,
Number | Date | Country | Kind |
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10203499.0 | Jan 2002 | DE | national |
Filing Document | Filing Date | Country | Kind |
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PCT/DE02/04488 | 12/7/2002 | WO |