Method for automatically operating a vehicle's windshield wiper

Abstract

Method for automatically operating a windscreen wiper (7, 8) of a vehicle (1), comprising: - automatic detection of the amount of moisture on a windshield (3) of the vehicle (1), - automatic detection of ambient brightness in the vicinity of the vehicle (1), - automatic acquisition of image information from an area in the direction of travel in front of the vehicle (1), - automatically determining from the image information whether there is an oncoming vehicle in the area in front of the vehicle (1) in the direction of travel, - automatic control of the windshield wipers (7, 8) of the vehicle (1) depending on the amount of moisture detected on the windshield (3), the ambient brightness and whether there is an oncoming vehicle in the area in front of the vehicle (1) in the direction of travel, and - automatic activation of a high beam (10) of the vehicle (1) depending on whether an oncoming vehicle has been detected in the area in the direction of travel in front of the vehicle (1).

Description

[0001] The present invention relates to a method for automatically actuating a windshield wiper of a vehicle according to patent claims 1, 8 and 9, a windshield wiper control according to the preamble of patent claim 10, and a vehicle according to patent claim 11.

[0002] Modern vehicles, such as cars or trucks, are equipped with a rain sensor and a linked control system that detects the amount of moisture or raindrops on the vehicle's windshield and uses this information to automatically control the vehicle's windshield wiper. This reliably keeps the vehicle's windshield clear of moisture and raindrops, allowing the driver an unobstructed view without being distracted by operating the wiper.

[0003] In this context, DE 10 2004 061 831 A1 provides a method and a device for the combined evaluation of signals from a rain sensor and a camera. In this method, if a positive rain signal is detected and a preceding and / or oncoming vehicle is detected, an additional signal for an expected water splash on the windshield is applied to a windshield wiper control.

[0004] DE 197 56 504 A1 provides a control device for a windscreen wiper device which can be activated by means of a manually operated wiper switch and automatically controls a drive motor of the windscreen wiper device in a switching stage of the wiper switch according to a characteristic curve depending on a signal from a rain sensor, wherein the operating data for the drive motor can be changed depending on the lighting and / or temperature and / or driving speed influences acting on the vehicle from the outside.

[0005] DE 42 00 700 A1 discloses a device for automatically controlling a wiper motor of a wiper system for motor vehicles. The device includes a rain sensor whose output signal is fed to an amplifier that can be connected to an interval control circuit for the wiper motor. The amplifier is provided with external circuitry for automatically varying its amplification factor, and the external circuitry is influenced depending on the ambient brightness such that the amplification factor is increased as darkness increases. Preferably, the amplification factor is variable depending on a glare sensor that detects brightness fluctuations caused by oncoming vehicles.

[0006] DE 103 16 794 A1 relates to a rain sensor for a motor vehicle with a camera and an associated image processing unit. The camera is aimed at an object fixed to the vehicle in front of the windshield, and the image processing unit is designed to compare the image captured by the camera with a stored image of the object captured when the windshield is dry, and to detect moisture on the windshield based on detected deviations between the images. The camera and the image processing unit can be part of a driver assistance system.

[0007] DE 10 2006 016 774 A1 discloses a rain sensor arranged in a vehicle and comprising a camera and a processor. The camera captures an image of a scene outside the vehicle through a windshield of the vehicle with an infinite focal length. The processor detects rain based on the degree of dispersion of pixel intensities in the image compared to an average pixel intensity.

[0008] At night, the driver's sensitivity to glare increases significantly, especially when there is oncoming traffic and rain on the windshield. For this reason, as can be seen from the state of the art cited above, the sensitivity of the rain sensor is increased in the dark. However, in driving situations without oncoming traffic, this general increase in sensitivity leads to the rain sensor triggering wiper strokes that are implausible from the driver's perspective.

[0009] The object of the present invention is therefore to provide an improved method for automatically actuating a windshield wiper, which avoids implausible wiping cycles and can nevertheless be implemented cost-effectively.

[0010] This object is achieved according to the present invention by a method for automatically actuating a windshield wiper of a vehicle according to claim 1, 8 or 9, by a windshield wiper control according to claim 10 and by a vehicle according to claim 11.

[0011] The dependent claims define preferred and advantageous embodiments of the invention.

[0012] According to the present invention, a method for automatically actuating a windshield wiper for a vehicle is provided. In the method, an amount of moisture on a windshield of the vehicle is automatically detected. The amount of moisture can, for example, comprise the amount of raindrops in a specific area of ​​the windshield. Furthermore, an ambient brightness in the area surrounding the vehicle, i.e., for example, outside the vehicle, is automatically detected. Image information is automatically detected in an area in front of the vehicle in the direction of travel, and it is automatically determined from the image information whether there is an oncoming vehicle in the area in front of the vehicle in the direction of travel. The amount of moisture on the windshield detected, the ambient brightness, and whether there is an oncoming vehicle in the area in front of the vehicle in the direction of travel, determines whether there is an oncoming vehicle in the area in the direction of travel.If an oncoming vehicle is located, the vehicle's windshield wiper is automatically activated. The detection of the amount of moisture on the vehicle's windshield can be carried out using devices known in the art. The automatic detection of image information of the area in front of the vehicle in the direction of travel and the automatic determination therefrom of whether an oncoming vehicle is located in the area in front of the vehicle in the direction of travel can be carried out, for example, with the aid of a camera-based light assistance system in the vehicle. This enables a cost-effective implementation of the method for automatically actuating the windshield wiper. The light assistance system can, for example, automatically control the vehicle's high beam depending on whether an oncoming vehicle has been detected in the area in front of the vehicle in the direction of travel.The described method can be used, in particular, to control a windshield wiper for wiping a vehicle's windshield. Furthermore, it is also possible to control headlight wipers, for example.

[0013] According to one embodiment, an immediate wipe cycle is performed when the windshield wiper is automatically activated. This reliably prevents the driver from being dazzled by raindrops on the windshield when oncoming traffic suddenly appears, by immediately wiping the windshield.

[0014] According to a further embodiment, the automatic control of the windshield wiper includes setting a wiping interval between two wiping operations. For example, if no oncoming vehicle is detected, a wiping interval can be used that would normally be used during the day. However, if an oncoming vehicle is detected, the wiping interval can be shortened to avoid dazzling the driver due to droplets on the windshield.

[0015] According to a further embodiment, the automatic control of the windshield wiper includes adjusting the wiping speed of a wiping operation of the windshield wiper. In this way, the wiping speed can be increased in heavy rain as soon as an oncoming vehicle is detected in the dark to avoid dazzling the driver.

[0016] According to one embodiment, depending on the detected ambient brightness, either a day mode or a night mode is selected, and the windshield wiper is automatically controlled depending on the selected mode. This allows simple and reliable control of the windshield wiper. If a certain ambient brightness is not reached, i.e., if a night mode is selected, the information regarding whether a vehicle is approaching from the front is used to decide how the amount of moisture on the windshield detected by a rain sensor is used to control the windshield wiper. As long as no vehicle is detected from the front, the windshield wiper control in night mode can essentially correspond to the control in day mode.If a vehicle is detected from the front, the wiping frequency or speed can be increased and, depending on the amount of moisture or droplets already on the windscreen, a wiping cycle can be carried out immediately.

[0017] According to the present invention, a windshield wiper controller for a vehicle is further provided. The windshield wiper controller comprises a first detection port for coupling the windshield wiper controller to a rain sensor for detecting an amount of moisture on a windshield of the vehicle, and a second detection port for coupling the windshield wiper controller to a brightness sensor for detecting ambient brightness in the surroundings of the vehicle. The windshield wiper controller further comprises a third detection port for coupling the windshield wiper controller to an image detection and processing unit. The image detection and processing unit is configured to detect image information of an area in front of the vehicle in the direction of travel and to determine therefrom whether an oncoming vehicle is located in the area in front of the vehicle in the direction of travel.The windshield wiper control is coupled to a windshield wiper of the vehicle via a windshield wiper control connection, for example, to adjust the wiping frequency and speed of the windshield wiper. A processing unit of the windshield wiper control is configured to control the windshield wiper depending on the detected amount of moisture on the windshield, the detected ambient brightness, and whether there is an oncoming vehicle in the area in front of the vehicle in the direction of travel.

[0018] The windshield wiper control is therefore designed to be suitable for implementing the previously described method for automatically actuating the windshield wiper. Therefore, the windshield wiper control provides reliable control, particularly for a windshield wiper of a vehicle's windshield, which ensures optimal wiping frequency and speed, especially in darkness, rain, and oncoming traffic.

[0019] According to the present invention, a vehicle is further provided which has a rain sensor, a brightness sensor, an image capture and processing device, a windshield wiper and a windshield wiper control. The rain sensor is used to detect an amount of moisture on a windshield of the vehicle and the brightness sensor is designed to detect ambient brightness in the surroundings of the vehicle. The image capture and processing device is used to detect image information in an area in front of the vehicle in the direction of travel and determines from this whether an oncoming vehicle is located in the area in front of the vehicle in the direction of travel. The windshield wiper control is coupled to the rain sensor, the brightness sensor, the image capture and processing device and the windshield wiper. Depending on the detected image information, the windshield wiper is controlled by the rain sensor, the brightness sensor, the image capture and processing device and the windshield wiper.The windshield wiper control activates the windshield wiper based on the amount of moisture on the windshield, the detected ambient brightness and whether there is an oncoming vehicle in the area in front of the vehicle in the direction of travel.

[0020] The vehicle may further comprise a high beam for illuminating an area in front of the vehicle and a high beam control. The high beam control is coupled to the high beam and the image capture and processing device and is configured to control the vehicle's high beam depending on whether an oncoming vehicle is located in the area in front of the vehicle in the direction of travel. Furthermore, the high beam control can use further information from the image information in the area in front of the vehicle in the direction of travel to control the high beam, such as whether a vehicle driving ahead is located in the area in front of the vehicle in the direction of travel. By using the image capture and processing device for both the high beam control and the windshield wiper control, a cost-effective implementation of the windshield wiper control can be achieved.In addition, the image capture and processing device provides particularly reliable information as to whether there is an oncoming vehicle in the area in the direction of travel in front of the vehicle, so that reliable and accurate windshield wiper control for the vehicle can be achieved.

[0021] The present invention is explained below with reference to the drawings using preferred embodiments.

[0022] The single figure shows a vehicle with a windshield wiper control according to an embodiment of the present invention.

[0023] The single figure shows a vehicle 1 with a windshield 3 and a headlight with a high beam 10. A windshield wiper 8 is located on the windshield 3 for wiping the windshield 3. The windshield wiper 8 is driven by a windshield wiper motor 7. A brightness sensor 4 is arranged, for example, in the area of ​​the windshield 3 such that it detects an ambient brightness of the surroundings of the vehicle 1. A rain sensor 2 is attached to the windshield 3 in a wiping area of ​​the windshield wiper 8 in order to detect an amount of moisture or a quantity of droplets in the wiping area on the windshield 3. The vehicle 1 further comprises an image capture device 5, such as a camera, which is arranged such that it can capture an area in front of the vehicle in the direction of travel.The camera 5 can, for example, be arranged in the area of ​​a front bumper of the vehicle, as shown in the figure, or, for example, be arranged adjacent to or integrated with the rain sensor 2 in the wiping area of ​​the windshield 3. The camera 5 is assigned an image processing device 6, which analyzes and evaluates the image captured by the camera 5, for example to provide a signal indicating whether or not there is an oncoming vehicle in the area in front of the vehicle in the direction of travel. The vehicle 1 further comprises a windshield wiper control 9, which has a plurality of connections 12-14 for detecting information for the windshield wiper control 9. A first detection connection 12 is coupled to the rain sensor 2 to detect information about an amount of moisture or droplets on the windshield.A second detection terminal 13 is coupled to the brightness sensor 4 for detecting the ambient brightness. A third detection terminal 14 is coupled, for example, via a vehicle bus to the image processing device 6 to detect information as to whether a vehicle is approaching from the front. The information detected via the detection terminals 12-14 is fed to a processing unit 16 of the windshield wiper control 9, and the processing unit 16 controls the windshield wiper motor 7 via a windshield wiper control terminal 15 depending on the detected information, as will be described in more detail below.

[0024] A day mode or a night mode is selected based on the ambient brightness determined by the brightness sensor 4. In day mode, the windshield wiper motor 7 is controlled depending on the amount of droplets detected by the rain sensor 2, essentially regardless of whether a vehicle was detected from the front. If the amount of droplets detected on the windshield increases, for example, the wiping interval between two wiping cycles of the windshield wiper 8 is initially reduced in order to ensure the driver an unobstructed view through the windshield 3. If it is no longer possible to reduce the interval between two wiping cycles, the wiping speed at which a wiping cycle is carried out can be increased. If a smaller amount of moisture or droplets is detected on the windshield 3, the wiping speed can be reduced again or the interval between two wiping operations can be increased.

[0025] If, however, a night mode is selected based on information from brightness sensor 4, for example because a predefined brightness threshold has been undershot, the control of windshield wiper motor 7 is additionally adjusted depending on the information from image processing device 6 regarding whether a vehicle has been detected from the front. If a vehicle is detected from the front, the rain sensor sensitivity is increased, i.e., the wiping interval between two wiping operations is reduced more than in daytime mode, or the wiping speed is increased more than in daytime mode. Furthermore, a wiping cycle can be performed immediately if there is already a significant amount of moisture on the windshield and a vehicle is detected from the front.This means that if a vehicle suddenly appears from the front, for example after a bend or a vehicle turning in, a wiping cycle is carried out immediately to prevent the driver from being dazzled by the oncoming light scattering on drops on the windshield.

[0026] The vehicle 1 further comprises a high beam control 11, which is coupled to the image processing device 6 and the high beam 10. The high beam control 11 controls the high beam 10 depending on information from the image processing device 6. The information from the image processing device 6 indicates, for example, whether there is a vehicle driving ahead of the vehicle or whether there is an oncoming vehicle in front of the vehicle. If a vehicle driving ahead or an oncoming vehicle is detected, the high beam 10 is switched off to prevent dazzling the driver of the vehicle driving ahead or an oncoming vehicle. By using the image capture device 6 for both the high beam control 11 and the windshield wiper control 9, a cost-effective implementation of the windshield wiper control in particular is possible.

[0027] The joint use of the image capture device 5 and the image processing device 6 for the windshield wiper control 9 and the high beam control 11 is merely a non-limiting example. The windshield wiper control 9 can also be used, for example, with an image capture device 5 and an image processing device 6 of another assistance system of the vehicle, such as a lane departure warning system or a distance control system, to ensure a cost-effective implementation of the windshield wiper control. Furthermore, the windshield wiper control can also have its own image capture device 5 and an image processing device 6.If the image capture device 5 and the image processing device 6 are used jointly by the windshield wiper control 9 and another assistance system of the vehicle, such as a high beam assistant or a lane keeping assistant, a signal conversion of the information from the image processing device 6 may be required in order to provide the captured image information to the windshield wiper control 9 in a suitable manner. This signal conversion can, for example, be integrated into the image processing device 6. Alternatively, raw data information can also be forwarded from the image capture device 5 and the image processing device 6 to the windshield wiper control 9, which evaluates the image data to determine whether an oncoming vehicle is located in the area in front of the vehicle in the direction of travel.Information transmission between the image processing device 6, the high beam control 11, other (not shown) assistance systems of the vehicle and / or the windshield wiper control 9 can be carried out, for example, directly via a bus system of the vehicle or via a (not shown) central control system of the vehicle. List of reference symbols 1 vehicle 2 rain sensors 3 Windshield 4 Brightness sensor 5 Image capture device, camera 6 Image processing device, signal converter 7 Windshield wiper motor 8 windshield wipers 9 Windscreen wiper control 10 High beam 11 High beam control 12 first detection connection 13 second detection connection 14 third detection connection 15 Windscreen wiper control connection 16 processing unit

Claims

[1] Method for automatically actuating a windscreen wiper (7, 8) of a vehicle (1), comprising: - automatic detection of the amount of moisture on a windscreen (3) of the vehicle (1), - automatic detection of ambient brightness in the area surrounding the vehicle (1), - automatic acquisition of image information from an area in the direction of travel in front of the vehicle (1), - automatically determining from the image information whether there is an oncoming vehicle in the area in the direction of travel in front of the vehicle (1), - automatic control of the windscreen wiper (7, 8) of the vehicle (1) as a function of the amount of moisture detected on the windscreen (3), the ambient brightness and whether there is an oncoming vehicle in the area in the direction of travel in front of the vehicle (1), and - automatic control of a high beam (10) of the vehicle (1) depending on whether an oncoming vehicle has been determined in the area in the direction of travel in front of the vehicle (1). [3] Method according to claim 1, characterized by that the windscreen wiper (7, 8) comprises a front windscreen wiper (8) for wiping a front windscreen (3) of the vehicle (1). [4] Method according to one of the preceding claims, characterized by that the automatic control of the windscreen wiper (7, 8) comprises setting a wiping speed of a wiping operation of the windscreen wiper (7, 8). [5] Method according to one of the preceding claims, characterized by that a day mode or a night mode is selected depending on the detected ambient brightness, wherein the windscreen wiper (7, 8) is automatically controlled depending on the selected mode. [6] Method according to claim 5, characterized bythat when the night mode has been selected and an oncoming vehicle has been determined in the area in the direction of travel in front of the vehicle (1), an immediate wiping cycle is carried out, a wiping interval between two wiping operations is reduced and / or a wiping speed is increased. [7] Method according to one of the preceding claims, characterized by that, if no oncoming vehicle has been detected in the area in the direction of travel in front of the vehicle (1), the windscreen wiper (7, 8) is automatically controlled only as a function of the amount of moisture detected on the windscreen. [8] Method for automatically actuating a windscreen wiper (7, 8) of a vehicle (1), comprising: - automatic detection of the amount of moisture on a windscreen (3) of the vehicle (1), - automatic detection of ambient brightness in the area surrounding the vehicle (1), - automatic acquisition of image information from an area in the direction of travel in front of the vehicle (1), - automatically determining from the image information whether there is an oncoming vehicle in the area in the direction of travel in front of the vehicle (1), and - automatically controlling the windscreen wiper (7, 8) of the vehicle (1) as a function of the amount of moisture detected on the windscreen (3), the ambient brightness and whether there is an oncoming vehicle in the area in the direction of travel in front of the vehicle (1), wherein the automatic control of the windscreen wiper (7, 8) comprises executing an immediate wiping cycle of the windscreen wiper (7, 8) and / or setting a wiping interval between two wiping operations of the windscreen wiper (7, 8). [9] Method for automatically actuating a windscreen wiper (7, 8) of a vehicle (1), comprising: - automatic detection of the amount of moisture on a windscreen (3) of the vehicle (1), - automatic detection of ambient brightness in the area surrounding the vehicle (1), - automatic acquisition of image information from an area in the direction of travel in front of the vehicle (1), - automatically determining from the image information whether there is an oncoming vehicle in the area in the direction of travel in front of the vehicle (1), and - automatic control of the windscreen wiper (7, 8) of the vehicle (1) as a function of the amount of moisture detected on the windscreen (3), of the ambient brightness and of whether there is an oncoming vehicle in the area in front of the vehicle (1) in the direction of travel, wherein the windscreen wiper control is used to control the windscreen wiper (7, 8) with an image capture device and an image processing device of another assistance system of the vehicle, namely a lane keeping assistant or a distance keeping assistant. [10] Windscreen wiper control for a vehicle, comprising: - a first detection connection (12) for coupling the windscreen wiper control (9) to a rain sensor (2) for detecting an amount of moisture on a windscreen (3) of the vehicle (1), - a second detection connection (13) for coupling the windscreen wiper control (9) to a brightness sensor (4) for detecting an ambient brightness in the surroundings of the vehicle (1), - a third detection connection (14) for coupling the windscreen wiper control (9) to an image detection and processing device (5, 6) for detecting image information from an area in the direction of travel in front of the vehicle (1) and for determining whether there is an oncoming vehicle in the area in the direction of travel in front of the vehicle (1), - a windscreen wiper control connection (15) for coupling the windscreen wiper control (9) to a windscreen wiper (7, 8) of the vehicle (1) for controlling the windscreen wiper (7, 8), and - a processing unit (16) which is designed to control the windscreen wiper (7, 8) depending on the detected amount of moisture on the windscreen (3), on the detected ambient brightness and on whether there is an oncoming vehicle in the area in the direction of travel in front of the vehicle (1), characterized by that the windscreen wiper control (9) is designed to carry out the method according to one of claims 1-9. [11] Vehicle comprising: - a rain sensor (2) for detecting an amount of moisture on a windscreen (3) of the vehicle (1), - a brightness sensor (4) for detecting ambient brightness in the surroundings of the vehicle (1), - an image capturing and processing device (5, 6) for capturing image information from an area in the direction of travel in front of the vehicle (1) and for determining whether there is an oncoming vehicle in the area in the direction of travel in front of the vehicle (1), - a windscreen wiper (7, 8), and - a windscreen wiper control (9) according to claim 10, which is coupled to the rain sensor (2), the brightness sensor (4), the image capture and processing device (5, 6) and the windscreen wiper (7). [12] The vehicle of claim 11, further comprising: - a high beam (10) for illuminating an area in front of the vehicle (1), and - a high beam control (11) which is coupled to the high beam (10) and the image capture and processing device (5, 6) and is designed to control the high beam (10) of the vehicle (1) depending on whether there is an oncoming vehicle in the area in the direction of travel in front of the vehicle (1).

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