BLIND-SPOT WARNING

Abstract

The invention relates to a sensor arrangement (12), in particular for use for a driving assistance system of a vehicle (10), having a plurality of ultrasonic sensors (14) which are arranged along at least a front (20) and/or a rear (22) of the vehicle (10), wherein the ultrasonic sensors (14) are divided into a group (26) of right-hand ultrasonic sensors (14) and a group (24) of left-hand ultrasonic sensors (14), and the sensor arrangement (12) has asymmetric operation in which the ultrasonic sensors (14) in one group (24, 26) of ultrasonic sensors (14) at least partially have a lower receiving sensitivity than corresponding ultrasonic sensors (14) in the other group (26, 24) of ultrasonic sensors (14). The invention also relates to a method for operating such a sensor arrangement (12).

Claims

1. A sensor arrangement for use for a driving assistance system of a vehicle comprising a plurality of ultrasonic sensors which are arranged along at least a front and/or a rear of the vehicle wherein the ultrasonic sensors are divided into a group of right-hand ultrasonic sensors and a group of left-hand ultrasonic sensors, and wherein the sensor arrangement has asymmetric operation in which the ultrasonic sensors in one group of ultrasonic sensors at least partially have a lower receiving sensitivity than corresponding ultrasonic sensors in the other group of ultrasonic sensors.

2. The sensor arrangement as claimed in claim 1, wherein asymmetric operation has operation with a reduced sensitivity on the right-hand side and/or operation with a reduced sensitivity on the left-hand side, wherein, during operation with a reduced sensitivity on the right-hand side, the ultrasonic sensors in the group of right-hand ultrasonic sensors at least partially have a lower receiving sensitivity than corresponding ultrasonic sensors in the group of left-hand ultrasonic sensors, and, during operation with a reduced sensitivity on the left-hand side, the ultrasonic sensors in the group of left-hand ultrasonic sensors at least partially have a lower receiving sensitivity than corresponding ultrasonic sensors in the group of right-hand ultrasonic sensors.

3. The sensor arrangement as claimed in claim 1, wherein the group of ultrasonic sensors which, during asymmetric operation, at least partially have a lower receiving sensitivity than corresponding ultrasonic sensors in the other group of ultrasonic sensors has at least one subgroup of front ultrasonic sensors and one subgroup of rear ultrasonic sensors, wherein, during asymmetric operation, at least the subgroup of rear ultrasonic sensors at least partially has a lower receiving sensitivity than corresponding ultrasonic sensors in the other group of ultrasonic sensors.

4. The sensor arrangement as claimed in claim 1, wherein the ultrasonic sensors in the group of ultrasonic sensors which, during asymmetric operation, at least partially have a lower receiving sensitivity than corresponding ultrasonic sensors in the other group of ultrasonic sensors at least partially have a different degree of lower receiving sensitivity than corresponding ultrasonic sensors in the other group of ultrasonic sensors, depending on their position on the vehicle.

5. The sensor arrangement as claimed in claim 2, wherein the sensor arrangement has a control device which is connected to the plurality of ultrasonic sensors via a data connection, wherein the sensor arrangement is configured to change over the receiving sensitivity of at least one of the groups of ultrasonic sensors between normal operation, in which corresponding ultrasonic sensors in both groups have a substantially identical receiving sensitivity, and asymmetric operation, and/or to adapt asymmetric operation.

6. The sensor arrangement as claimed in claim 5, wherein the control device is configured to change over between normal operation and asymmetric operation and/or to adapt asymmetric operation, also taking into account a travel speed of the vehicle.

7. The sensor arrangement as claimed in claim 5, wherein the control device is configured to change over between normal operation and asymmetric operation and/or to adapt asymmetric operation, also taking into account a change in the direction of travel of the vehicle.

8. The sensor arrangement as claimed in claim 5, wherein the control device is configured to change over between normal operation and asymmetric operation and/or to adapt asymmetric operation, also taking into account a lane being used by the vehicle from a plurality of available directional lanes.

9. The sensor arrangement as claimed in claim 8, wherein the control device is configured to change over asymmetric operation between operation with a reduced sensitivity on the right-hand side and operation with a reduced sensitivity on the left-hand side, depending on a lane being used by the vehicle from a plurality of available directional lanes.

10. The sensor arrangement as claimed in claim 5, wherein the control device is configured to change over asymmetric operation between operation with a reduced sensitivity on the right-hand side and operation with a reduced sensitivity on the left-hand side, depending on a traffic mode with right-hand traffic or left-hand traffic.

11. The sensor arrangement as claimed in claim 5, wherein the control device is configured to change over between normal operation and asymmetric operation and/or to adapt asymmetric operation, also taking into account at least one environmental condition.

12. The sensor arrangement as claimed in claim 5, wherein the control device is configured to adjust the receiving sensitivity of the ultrasonic sensors in the group of ultrasonic sensors which, during asymmetric operation, at least partially have a lower receiving sensitivity than corresponding ultrasonic sensors in the other group of ultrasonic sensors between different receiving sensitivities.

13. A method for operating a sensor arrangement for use for a driving assistance system of a vehicle, having a plurality of ultrasonic sensors which are arranged along at least a front and/or a rear of the vehicle, wherein the ultrasonic sensors are divided into a group of right-hand ultrasonic sensorsand a groupof left-hand ultrasonic sensors, the method comprising: capturing switch actuation and/or at least one parameter from a travel speed, a change in the direction of travel, a lane being used by the vehiclefrom a plurality of available directional lanes, a traffic mode with right-hand traffic or left-hand traffic and at least one environmental condition, and changing over a receiving sensitivity of at least one of the groups of ultrasonic sensors between normal operation, in which corresponding ultrasonic sensorsin both groups have a substantially identical receiving sensitivity, and asymmetric operation, in which the ultrasonic sensors in one group of ultrasonic sensorsat least partially have a lower receiving sensitivity than corresponding ultrasonic sensorsin the other group of ultrasonic sensors, on the basis of the switch actuation and/or the at least one parameter.

14. The method as claimed in claim 13, method further comprising: adapting asymmetric operation on the basis of the switch actuation and/or the at least one parameter.

Description

IN THE FIGURES

[0041] FIG. 1 shows a schematic view of a vehicle with a sensor arrangement having a plurality of ultrasonic sensors according to a first preferred embodiment,

[0042] FIG. 2 shows a schematic view of the vehicle from FIG. 1 with detection areas of selected ultrasonic sensors of the sensor arrangement and areas of a blind spot of the vehicle,

[0043] FIG. 3 shows a schematic view of the vehicle from FIG. 1 on a road shown in cross section;

[0044] FIG. 4 shows a schematic view of the vehicle from FIG. 1 with spray thrown up behind the vehicle in the detection area of one of the ultrasonic sensors,

[0045] FIGS. 5a and 5b shows a schematic illustration of the vehicle from FIG. 1 when passing a road sign with an illustration of the vehicle directly next to the road sign and an illustration of the vehicle after passing the road sign,

[0046] FIG. 6 shows a schematic view of a vehicle with a sensor arrangement having a plurality of ultrasonic sensors and a control device according to a second embodiment, and

[0047] FIG. 7 shows a flowchart of a method for operating the sensor arrangement of the vehicle in FIG. 6.

[0048] FIG. 1 shows a vehicle 10 with a sensor arrangement 12 according to a first preferred embodiment.

[0049] In this exemplary embodiment, the sensor arrangement 12 is designed to be used for a driving assistance system of the vehicle 10. In this exemplary embodiment, the driving assistance system is a driving assistance system for blind spot monitoring, as will be explained further below.

[0050] The sensor arrangement 12 comprises a plurality of ultrasonic sensors 14 which are attached to the vehicle 10 for the purpose of capturing an environment 18 of the vehicle 10. The ultrasonic sensors 14 are arranged along a front 20 and a rear 22 of the vehicle 10. In addition, ultrasonic sensors 14 are arranged in side areas of the vehicle 10.

[0051] The ultrasonic sensors 14 are divided into a group 24 of right-hand ultrasonic sensors 14 and a group 26 of left-hand ultrasonic sensors 14, as emerges from FIG. 1. The ultrasonic sensors 14 are divided into the two groups 24, 26 along a central axis 28 of the vehicle 10 based on its longitudinal direction. Here, the group 24 of left-hand ultrasonic sensors 14 is formed by all the ultrasonic sensors 14 positioned to the left of the central axis 28 of the vehicle 10, and the group 26 of right-hand ultrasonic sensors 14 is formed by all the ultrasonic sensors 14 positioned to the right of the central axis 28 of the vehicle 10.

[0052] The ultrasonic sensors 14 in both groups 24, 26 are attached at the same positions based on the longitudinal axis 28 of the vehicle 10, as a result of which pairs of corresponding ultrasonic sensors 14 are formed in each case. Corresponding ultrasonic sensors 14 are additionally distinguished based on their distance from the central axis 28 of the vehicle 10.

[0053] In this exemplary embodiment, the vehicle 10 is in the form of a left-hand-drive vehicle, as indicated by the steering wheel 30 in FIG. 1. In this exemplary embodiment, the sensor arrangement 12 is configured for asymmetric operation in which the ultrasonic sensors 14 in the group 26 of right-hand ultrasonic sensors 14 partially have a lower receiving sensitivity than corresponding ultrasonic sensors 14 in the group 24 of left-hand ultrasonic sensors 14. The sensor arrangement 12 is therefore designed for asymmetric operation with a reduced sensitivity on the right-hand side. The vehicle 10 with the sensor arrangement 12 is thus optimized for a traffic mode with right-hand traffic.

[0054] In this exemplary embodiment, asymmetric operation relates to those ultrasonic sensors 14a which are used by the driving assistance system for blind spot monitoring. In this exemplary embodiment, these are a front, laterally oriented ultrasonic sensor 14a, a rear, laterally oriented ultrasonic sensor 14a and a rear, rearwardly oriented ultrasonic sensor 14a from each of the two groups 24, 26 of ultrasonic sensors 14, as shown in FIG. 1. Correspondingly, the detection areas 32 of some ultrasonic sensors 14 of the sensor arrangement 12 are shown in FIG. 2, wherein the detection areas 32a of the ultrasonic sensors 14a which are used by the driving assistance system are accordingly shown in comparison with the detection areas 32b of the ultrasonic sensors 14b which are not used by the driving assistance system. For reasons of clarity, the detection areas 32 of all ultrasonic sensors 14 are not shown in the illustration in FIG. 2. Ultrasonic sensors 14b not used for blind spot monitoring are marked accordingly.

[0055] The ultrasonic sensors 14 in the group 26 of right-hand ultrasonic sensors 14 is additionally divided into a subgroup 34 of front ultrasonic sensors 14 and a subgroup 36 of rear ultrasonic sensors 14. In this case, the subgroup 36 of rear ultrasonic sensors 14 is designed with a lower receiving sensitivity than corresponding ultrasonic sensors 14 in the group 24 of left-hand ultrasonic sensors 14. In this exemplary embodiment, the receiving sensitivity of the subgroup 36 of rear ultrasonic sensors 14 is configured directly on the respective ultrasonic sensor 14. In detail, a signal threshold, i.e. a signal level, of a sensor signal from the respective ultrasonic sensor 14 is increased. The corresponding ultrasonic sensors 14 therefore output a warning based on a received sensor signal from the respective ultrasonic sensor 14 if the signal threshold is exceeded. Alternatively or additionally, the lower receiving sensitivity can be achieved by increasing a period of time over which a sensor signal must detect an object in order to output a warning. In this exemplary embodiment, the ultrasonic sensor 14 in the subgroup 34 of front ultrasonic sensors 14 has the same sensitivity as the corresponding ultrasonic sensor 14 in the group 24 of left-hand ultrasonic sensors 14.

[0056] The driving assistance system outputs a corresponding blind spot warning when an object is detected in a blind spot 38 based on the ultrasonic sensors 14a used by the driving assistance system for blind spot monitoring. The blind spot 38 is shown here on each side of the vehicle 10 along with a front blocking zone 42. The two blind spots 38 each comprise a necessary alarm zone 44 and an optional alarm zone 46. Accordingly, a blind spot warning can be triggered when the object in the optional alarm zone 46 approaches the vehicle 10, while a blind spot warning must be triggered when the object in the necessary alarm zone 44 approaches the vehicle 10. A blind spot warning is to be blocked in the blocking zone 42. These zones 42, 44, 46 are based on an ISO standard and are universally known in this form.

[0057] FIGS. 3 and 4 illustrate the improvement in the sensor arrangement 12 for carrying out the blind spot monitoring with the driving assistance system when spray occurs. FIG. 3 shows a profile of a road 50 on which the vehicle 10 is located. The road 50 has a central elevation 52. There is a lower edge elevation 54 in each edge area of the road 50. There is a dip 56 between each of the edge elevations 54 and the central elevation 52. In addition, road ditches 58 and side vegetation 60 are shown in FIG. 3. The profile of the road 50 causes moisture to run off laterally in the direction of the road ditches 58, as a result of which there is typically less moisture on the road 50 in the area of the central elevation 52 than in the area of the edge elevations 54 and in particular the dips 56.

[0058] As shown in FIG. 4, this profile of the road 50 causes the vehicle 10 to produce more spray 62 behind the vehicle 10 on the right-hand side than on the left-hand side when driving on the road 50. Incorrect detections of objects by the group 26 of right-hand ultrasonic sensors 14 can be reduced by asymmetric operation. FIG. 4 shows by way of example only the detection area 32a of an ultrasonic sensor 14a used by the driving assistance system.

[0059] FIG. 5 illustrates the improvement in the sensor arrangement 12 for carrying out the blind spot monitoring with the driving assistance system for road signs 64 located on a right-hand edge of a road. When passing the road sign 64, only slight reflections are produced by a side face of the road sign 64 facing the vehicle 10, with the result that the road sign 64 is not detected, as shown in FIG. 5a). After passing the road sign 64, as shown in FIG. 5b), a front or rear surface of the road sign 64 can cause stronger reflections, as a result of which the road sign 64 is detected. However, road signs 64 are part of fixed installations, and so the detection of road signs 64 is not desired. Incorrect detections of road signs 64 as objects by the group 26 of right-hand ultrasonic sensors 14 can therefore also be reduced by asymmetric operation. This relates to the subgroup 36 of rear ultrasonic sensors 14, since the road signs 64 in the area of the subgroup 34 of front ultrasonic sensors 14 are usually not detected.

[0060] A second exemplary embodiment will be described below with reference to FIGS. 6 and 7. The second exemplary embodiment is based on the vehicle 10 with the sensor arrangement 12 of the first exemplary embodiment, and so only differences between the two exemplary embodiments are described in detail in the description.

[0061] The structure of the sensor arrangement 12 of the second exemplary embodiment is shown in FIG. 6 and differs from the sensor arrangement 12 of the first exemplary embodiment in that the sensor arrangement 12 of the second exemplary embodiment additionally has a control device 16. The control device 16 is connected to the ultrasonic sensors 14 via a data connection in a manner not shown in detail here. The data connection is implemented here in the manner of a data bus, in particular as a CAN bus known per se or another data bus used in the automotive sector.

[0062] In this exemplary embodiment, the control device 16 is designed to adjust the ultrasonic sensors 14. Alternatively, the control device 16 can also receive sensor signals from the connected ultrasonic sensors 14 and generate warnings based thereon. In this alternative exemplary embodiment, the control device 16 can be an integral part of the driving assistance system for blind spot monitoring.

[0063] The control device 16 of the second exemplary embodiment is designed to change over the receiving sensitivity of the groups 24, 26 of left-hand and right-hand ultrasonic sensors 14 between normal operation, in which corresponding ultrasonic sensors 14 in both groups 24, 26 have a substantially identical receiving sensitivity, and asymmetric operation, in which corresponding ultrasonic sensors 14 in a group 24, 26 partially have a lower receiving sensitivity than corresponding ultrasonic sensors 14 in the other group 26, 24 of ultrasonic sensors 14. In this case, the control device 16 can alternatively set a lower receiving sensitivity in the group 24 of left-hand ultrasonic sensors 14 or in the group 26 of right-hand ultrasonic sensors 14. Correspondingly, the control device 16 can set asymmetric operation with a reduced sensitivity on the right-hand side or with a reduced sensitivity on the left-hand side. As described above with reference to the first exemplary embodiment, the two groups 24, 26 of ultrasonic sensors 14 are divided into a subgroup 34, 36 of front and rear ultrasonic sensors 14, wherein the setting by the control device 16 here also affects a change only of the ultrasonic sensors 14 in the subgroup 36 of rear ultrasonic sensors 14. Likewise, asymmetric operation in the second exemplary embodiment relates only to those ultrasonic sensors 14a which are used by the driving assistance system for blind spot monitoring. Reference is made to the above explanations in relation to the sensor arrangement 12 of the first exemplary embodiment. In addition, the control device 16 can adapt asymmetric operation with a reduced sensitivity on the right-hand side as well as with a reduced sensitivity on the left-hand side.

[0064] The control device 16 is designed to automatically change over and/or adapt asymmetric operation. Various parameters are taken into account for the automatic changing over and/or adaptation of asymmetric operation, as will become apparent in detail from the explanations below.

[0065] In addition, the control device 16 is designed to capture switch actuation of a switch (not shown) of the vehicle 10. The switch can be implemented by a software configuration in the vehicle 10. The switch actuation relates to an indication of a traffic mode with right-hand traffic or left-hand traffic. The control device 16 is also designed to define and set operation with a partially reduced sensitivity on the right-hand or left-hand side as a default setting in accordance with the traffic mode that has been set. Correspondingly, in the case of right-hand traffic, asymmetric operation is set as operation with a partially reduced sensitivity on the right-hand side, and, in the case of left-hand traffic, asymmetric operation is set as operation with a partially reduced sensitivity on the left-hand side. Alternatively, the traffic mode is determined based on data from a global navigation satellite system (GNSS).

[0066] The control device 16 is designed to receive a signal indicating a travel speed of the vehicle 10, for example based on odometry information relating to the vehicle 10 or based on satellite navigation signals. The control device 16 is also designed to change over between normal operation and asymmetric operation, either on the right-hand side or on the left-hand side, also taking into account the travel speed of the vehicle 10. Asymmetric operation is started, for example, from a limit speed of 40 to 50 km/h.

[0067] The control device 16 is designed to receive a signal indicating a change in the direction of travel of the vehicle 10, for example a signal relating to turn signal actuation or a steering lock of vehicle 10. The change in the direction of travel can include turning, cornering or a lane change. The change in the direction of travel can be currently being carried out or can be currently imminent. The control device 16 is also designed to change over between normal operation and asymmetric operation, also taking into account the change in the direction of travel of the vehicle 10. The change in the direction of travel relates here to a change in the direction of travel toward that side of the vehicle 10 on which the ultrasonic sensors 14 in the group 24, 26 of ultrasonic sensors 14 which, during asymmetric operation, partially have a lower receiving sensitivity than corresponding ultrasonic sensors in the other group 26, 24 of ultrasonic sensors 14 are located. In the case of asymmetric operation on the right-hand side, a change in the direction of travel of the vehicle 10 to the right is therefore evaluated, and vice versa in the case of asymmetric operation on the left-hand side. When the direction of travel is changed, current asymmetric operation is therefore temporarily deactivated until the change in the direction of travel has been completed.

[0068] The control device 16 is designed to receive a signal indicating actuation of a windshield wiper of the vehicle 10 as an environmental condition of the vehicle 10. As a result, it can be concluded that it is raining, and so an increased occurrence of spray 62 can be expected. The control device 16 is accordingly designed to activate asymmetric operation only when the windshield wiper is actuated. In addition, the receiving sensitivity of the corresponding ultrasonic sensors 14 can be adjusted depending on an intensity of the actuation of the windshield wiper.

[0069] The control device 16 is designed to receive a signal indicating a lane being used from a plurality of available directional lanes. The signal may be generated based on capture of the environment 18 of the vehicle 10 with a camera and/or another environmental sensor. Alternatively or additionally, based on data from a global navigation satellite system (GNSS) together with corresponding map information, it is possible to detect whether a plurality of directional lanes are available and/or which of the directional lanes is being used by the vehicle 10.

[0070] The control device 16 is also designed to change over between normal operation and asymmetric operation and/or to adapt asymmetric operation and to change over asymmetric operation between operation with a reduced sensitivity on the right-hand side and operation with a reduced sensitivity on the left-hand side, also taking into account a lane being used by the vehicle 10 from a plurality of available directional lanes.

[0071] Accordingly, the control device 16 - starting from right-hand traffic - sets asymmetric operation with a reduced sensitivity on the right-hand side when driving in a right-hand lane, while asymmetric operation with a reduced sensitivity on the left-hand side is set when driving in a left-hand lane. Asymmetric operation is deactivated when driving in a middle lane. The previously stated conditions continue to apply in this case.

[0072] A method for operating the sensor arrangement 12 of the second exemplary embodiment will be described below.

[0073] Step S100 relates to capturing switch actuation and/or at least one parameter described above from the travel speed, the change in the direction of travel, the lane being used by the vehicle 10 from a plurality of available directional lanes, the traffic mode with right-hand traffic or left-hand traffic and the environmental condition.

[0074] Step S110 relates to changing over the receiving sensitivity of the subgroup 36 of rear ultrasonic sensors 14 in one of the groups 24, 26 of ultrasonic sensors 14 between normal operation, in which corresponding ultrasonic sensors 14 in both groups 24, 26 have a substantially identical receiving sensitivity, and asymmetric operation, in which the subgroup 36 of rear ultrasonic sensors 14 in one group 24, 26 of ultrasonic sensors 14 at least partially has a lower receiving sensitivity than corresponding ultrasonic sensors 14 in the other group 26, 24 of ultrasonic sensors 14, on the basis of the switch actuation and/or the at least one parameter.

[0075] Step S120 additionally relates to adapting asymmetric operation on the basis of the switch actuation and/or the at least one parameter. The principles described in detail above regarding the adaptation of asymmetric operation apply. In this exemplary embodiment, adapting asymmetric operation comprises selecting between operation with a reduced sensitivity on the right-hand side and operation with a reduced sensitivity on the left-hand side, as well as adjusting the subgroup 36 of rear ultrasonic sensors 14 which, during asymmetric operation, at least partially have a lower receiving sensitivity than corresponding ultrasonic sensors 14 in the other group 26, 24 of ultrasonic sensors 14 between different receiving sensitivities.

TABLE-US-00001 List of reference signs 10 Vehicle 12 Sensor arrangement 14 Ultrasonic sensor 14a Ultrasonic sensor used by driving assistance system 14b Ultrasonic sensor not used by driving assistance system 16 Control device 18 Environment 20 Front 22 Rear 24 Group of left-hand ultrasonic sensors 26 Group of right-hand ultrasonic sensors 28 Central axis 30 Steering wheel 32 Detection area 32a Detection area 32b Detection area 34 Subgroup of front ultrasonic sensors 36 Subgroup of rear ultrasonic sensors 38 Blind spot 42 Blocking zone 44 Necessary alarm zone 46 Optional alarm zone 50 Road 52 Central elevation 54 Edge elevation 56 Dip 58 Road ditch 60 Vegetation 62 Spray 64 Road sign