METHOD AND DEVICE FOR DETERMINING A TYPE OF THE ROAD WHICH A VEHICLE IS DRIVING

Abstract

The invention relates to a method for determining a type of the road on which a vehicle is driving. The method comprises sensing a sound of a wheel of the vehicle which is rolling on the road by means of a microphone and/or sensing a vertical acceleration of the vehicle by means of a vertical acceleration sensor or sensing a suspension of the vehicle by means of a suspension sensor and determining the type of the road on the basis of the sensed sound and/or the sensed acceleration or the sensed suspension. Further, the invention relates to a device for carrying out the aforesaid method.

Claims

1. A method for determining a type of the road on which a vehicle is driving, the method comprising the steps of: using a microphone to sense a sound of a wheel of the vehicle which is rolling on the road; using a vertical acceleration sensor to sense a vertical acceleration of the vehicle; using a suspension sensor to sense a suspension of the vehicle; determining the type of the road on the basis of at least one of the sensed sound, the sensed vertical acceleration, or the sensed suspension.

2. The method of claim 1, further comprising the steps of creating an environmental model of a vehicle which is driving on a road.

3. The method of claim 2, further comprising the steps of: detecting fused objects in the environment of the vehicle and a condition of the road on which the vehicle is driving by using at least one of a camera, a radar sensor, and a laser sensor; creating the environmental model by using at least one of the detected fused objects, condition of the road, and type of the road.

4. The method of claim 3, further comprising the steps of creating the environmental model based on a detection of road boundaries.

5. The method of claim 3, further comprising the steps of using the determined type of the road to support at least one safety function in an Advanced Driver Assistance System (ADAS).

6. The method of claim 1, further comprising the steps of using the determined type of the road to support at least one of a comfort function and an interior function in an Advanced Driver Assistance System (ADAS).

7. The method of claim 1, further comprising the steps of: using the determined type of the road in an Advanced Driver Assistance System (ADAS); using the ADAS to control the speed of the vehicle depending on the detected type of the road.

8. A device for determining a type of the road on which a vehicle is driving, the device comprising: a microphone for sensing a sound of a wheel of the vehicle rolling on the road; a vertical acceleration sensor for sensing a vertical acceleration of the vehicle; and a suspension sensor for sensing a suspension of the vehicle; wherein the device is adapted for determining the type of the road on the basis of at least one of the sensed sound, the sensed acceleration, or the sensed suspension.

9. The device according to claim 8, wherein the device is adapted for creating an environmental model of a vehicle which is driving on a road.

10. The device of claim 9, further comprising: a camera; a radar sensor; a laser sensor; wherein at least one of the camera, the radar sensor, or the laser sensor are used for detecting fused objects in the environment of the vehicle and a condition of the road on which the vehicle is driving, and the device is adapted for creating the environmental model by means of the detected fused objects, condition of the road and type of the road.

11. A method for determining a type of the road on which a vehicle is driving, the method comprising the steps of: using a microphone to sense a sound of a wheel of the vehicle which is rolling on the road; using a vertical acceleration sensor to sense a vertical acceleration of the vehicle; using a suspension sensor to sense a suspension of the vehicle; determining the type of the road on the basis of the sensed sound, the sensed vertical acceleration, and the sensed suspension.

12. The method of claim 11, further comprising the steps of creating an environmental model of a vehicle which is driving on a road.

13. The method of claim 12, further comprising the steps of: detecting fused objects in the environment of the vehicle and a condition of the road on which the vehicle is driving by using at least one of a camera, a radar sensor, and a laser sensor; creating the environmental model by using at least one of the detected fused objects, condition of the road, and type of the road.

14. The method of claim 13, further comprising the steps of creating the environmental model based on a detection of road boundaries.

15. The method of claim 13, further comprising the steps of using the determined type of the road to support at least one safety function in an Advanced Driver Assistance System (ADAS).

16. The method of claim 11, further comprising the steps of using the determined type of the road to support at least one of a comfort function and an interior function in an Advanced Driver Assistance System (ADAS).

17. The method of claim 11, further comprising the steps of: using the determined type of the road in an Advanced Driver Assistance System (ADAS); using the ADAS to control the speed of the vehicle depending on the detected type of the road.

Description

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0030] The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.

[0031] FIG. 1 shows a vehicle in form of a car 1 which is driving on a road 2. An upper layer 3 of the road 2 is made of asphalt and, thus, provides an asphalt road surface 4 (type of the road surface) on which the car 1 is driving by means of its four tyres 5 of its four wheels 6. In a first part 7 of the road 2 which is shown on the right in FIG. 1 the road surface 4 is plane (quality of the first part 7 of the road surface 4), whereas in a second part 8 of the road 2 which is shown on the left in FIG. 1 the road 2 comprises three potholes 9 (quality of the second part 7 of the road 2). Therefore, the type of the first part 7 of the road 2 may be described as an asphalt road with an almost plane road surface and the type of the second part 8 of the road 2 may be described as an asphalt road comprising potholes 9.

[0032] The car 1 comprises a device 10 for determining the type of the road 2 on which the car 1 is driving and for creating a model of an environment 11 of the car 1 which is driving on the road 2. The device 10 comprises an ADAS camera 12 which is situated behind a windshield 13 of the car 1. In a known manner the camera 12 detects fused objects in the environment 11 of the car 1 and a condition of the road 1 on which the car 1 is driving, in this example the camera 12 detects that the road 2 is dry and not coated with ice or something else. This is a first step 100 of the method which is illustrated by FIG. 2.

[0033] The device 10 further comprises a microphone 14 which is arranged on the outside of the car 1 nearby the left front wheel 6, such that rolling sounds of the wheel 6 while driving on the road 2 are sensed. Although the microphone 14 senses sounds in the shown embodiment, the sensing of only one sound would be sufficient for determining the type of the road 2 and for creating the environmental model. The microphone 14 is a digital microphone that records sounds and transmits digital data representing the recorded sounds to a control unit 15, e.g. an Electrical Control Unit (ECU), of the device 10 which is indicated by a dashed line between the microphone 14 and the control unit 15. In the shown exemplary embodiment the control unit 15 is part of an ADAS. The described sound recording is a second step 200 of the method which is illustrated by FIG. 2, wherein the second step 200 runs parallel to the first step 100, meaning that the first step 100 and the second step 200 may be executed at the same time.

[0034] The device 10 also comprises a vertical acceleration sensor 16 which senses relative vertical accelerations of the car 1. Although the acceleration sensor 16 senses relative vertical accelerations in the shown embodiment, the sensing of only one relative vertical acceleration would be sufficient for determining the type of the road 2 and for creating the environmental model. The vertical acceleration sensor 16 is a digital sensor that transmits digital data representing the sensed relative vertical accelerations to the control unit 15 of the device 10, which is indicated by a dashed line between the vertical acceleration sensor 16 and the control unit 15. In the shown example, the vertical acceleration sensor 16 is arranged at a chassis 17 of the car 1 and senses a relative acceleration of the chassis 17 with respect to the left front wheel 6 of the car 1. This is a third step 300 of the method which is illustrated by FIG. 2, wherein the third step 300 runs parallel to the first step 100 and the second step 200, meaning that the first step 100, the second step 200 and the third step 300 may be executed at the same time.

[0035] The control unit 15 determines the type of the road 2 on the basis of the data representing the recorded sounds and the data representing the sensed acceleration. This is a fourth step 400 of the method which is illustrated by FIG. 2, wherein the fourth step 400 follows the first three steps 100 to 300. In the shown example, the control unit 15 compares the received data representing the recorded sounds and the received data representing the sensed acceleration with data representing sound profiles and relative acceleration profiles according to specific road types which are stored in a database 18 in a memory unit of the control unit 15. If the received data match with one of the stored data, then the control unit 15 determines that a road type according to the matched data is given.

[0036] In the shown example the car 1 is driving on the first part 7 of the road 2, wherein almost no or just marginal vibrations will be exposed to the wheels 6. As a result, a relative acceleration between the chassis 17 of the car 1 and the left front wheel 6 is almost zero. The acceleration sensor 16 senses this and transmits respective data to the control unit 15. Further, the microphone 14 records almost uniform sounds with only small peaks and transmits respective data to the control unit 15. Also, the camera 12 detects the condition of the road 2 on which the car 1 is driving, in this example that the road 2 is dry and not coated with ice or something else. Respective data is transmitted from the camera 12, the microphone 14 and the acceleration sensor 16 to the control unit 15 where it is compared with the stored data representing sound profiles and relative acceleration profiles according to specific road types, The control unit 15 determines that the received data match with stored data representing an asphalt road with an almost plane road surface.

[0037] If the car 1 shown by FIG. 1 is driving on the second part 8 of the road 2, shocks are exposed to the wheels 6, e.g. while the wheels 6 are rolling into the potholes 9 and while the wheels 6 are rolling out of the potholes 9 again. As a result, a relative acceleration between the chassis 17 of the car and the front left wheel 6 occurs which is sensed by the acceleration sensor 16 which transmits respective data to the control unit 15. Further, the microphone 14 records noise peaks while the wheels 6 are rolling into the potholes 9 and while the wheels 6 are rolling out of the potholes 9 again and the microphone 14 transmits respective data to the control unit 15. Also, the camera 12 detects the condition of the road 2 on which the car 1 is driving, in this example that the road 2 is dry and not coated with ice or something else. Respective data is transmitted from the camera 12, the microphone 14 and the acceleration sensor 16 to the control unit 15 where it is compared with the stored data representing sound profiles and relative acceleration profiles according to specific road types. The control unit 15 determines that the received data match with stored data representing an asphalt road which comprises potholes 9.

[0038] In a subsequent fifth step 500 of the method which is illustrated by FIG. 2, e.g. the control unit 15 creates the environmental model by means of the detected fused objects, condition of the road 2 and type of the road 2.

[0039] FIG. 3 shows in a generalized way an example of a creation of an environmental model of a vehicle which is driving on a road, e.g. the car 1 which is driving on the road 2 and comprises a device 10 shown by FIG. 1. The device 10 mayas an alternative to the vertical acceleration sensor 16 or additionallycomprise a suspension sensor 19 which may be arranged in the area of a spring of a body work of the car 1. The suspension sensor 19 may sense temporal changes of length respectively compression of the spring of the body work.

[0040] In the shown example according to FIG. 1 the car 1 is driving on the first part 7 of the road 2, wherein almost no or just marginal vibrations will be exposed to the wheels 6. As a result, there probably will be no or just a small suspension of the springs because the springs do not have to compensate for a shock but just have to compensate for marginal vibrations. The suspension sensor 19 senses this. An accordingly suspension profile may e.g. have the form of that indicated with al in FIG. 3. Further, a microphone 14, e.g. the microphone 14 of the device 10 as per FIG. 1, records almost uniform sounds with only small peaks. Also, a camera 12, e.g. the camera 12 of the device as per FIG. 1, detects the condition of the road 2 on which the car 1 is driving, in this example that the road 2 is dry and not coated with ice or something else. Respective camera data is used as an input for a first environmental model EM1. Additional input data for the first environmental model may come from an optional ADAS radar sensor 20 and/or a LIDAR sensor 21 which especially may detect objects in the environment 11 of the car 1.

[0041] The first environmental model EM1 and data from the microphone 14 and the suspension sensor 19 serve as inputs for creating a second enhanced environmental model EM2 with fusion and hearing. This second enhanced environmental model EM2 includes inter alia the type of the road (determined on the basis of the sensed sounds and suspensions) and the first environmental model EM1 which includes the condition of the road (detected by the camera 12). For example, the second enhanced environmental model EM2 includes the information that the vehicle is driving on an asphalt road with an almost plane road surface. Additionally, the second environmental model EM2 may be based on a detection of road boundaries.

[0042] If the car 1 shown by FIG. 1 is driving on the second part 8 of the road 2 shocks are exposed to the wheels 6, e.g. while the wheels 6 are rolling into the potholes 9 and while the wheels 6 are rolling out of the potholes 9 again. As a result, the springs will be compressed and decompressed respectively there will be a suspension of the springs because the springs have to compensate for the shock. The suspension sensor 19 senses this. An accordingly suspension profile may e.g. have the form of that indicated with a2 in FIG. 3. Further, the microphone 14 records noise peaks (an exemplary sound profile is indicated by a3 in FIG. 3) while the wheels 6 are rolling into the potholes 9 and while the wheels 6 are rolling out of the potholes 9 again. Also, the camera 12 detects the condition of the road 2 on which the car 1 is driving, in this example that the road 2 is dry and not coated with ice or something else. In this situation, the second enhanced environmental model EM2 includes the information that the car 1 is driving on an asphalt road which is comprising potholes 9. The second enhanced environmental model EM2 servers as an input for an ADAS of the car 1. In this situation (car 1 is driving on an asphalt road which is comprising potholes 9) the ADAS automatically reduces the speed of the car 1. Thus, the determined type of the road 2 supports a safety, comfort respectively an interior function in an ADAS.

[0043] The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.

REFERENCE SIGNS

[0044] 1 car

[0045] 2 road

[0046] 3 upper layer of the road

[0047] 4 road surface

[0048] 5 tyre

[0049] 6 wheel

[0050] 7 first part of the road

[0051] 8 second part of the road

[0052] 9 pothole

[0053] 10 device

[0054] 11 environment of the car

[0055] 12 camera

[0056] 13 windshield

[0057] 14 microphone

[0058] 15 control unit

[0059] 16 vertical acceleration sensor

[0060] 17 chassis

[0061] 18 database

[0062] 19 suspension sensor

[0063] 20 radar sensor

[0064] 21 LIDAR sensor